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Posts Tagged ‘Clinical trial’


Clinical Trials Could Lead to FDA Approval for Artificial Pancreas

 Reported by: Irina Robu, PhD

Approximately 1.25 million American have type 1 diabetes accroding to the U.S. Centers for Disease Control and Prevention. A device that automatically monitors and regulates blood-sugar levels in people with type 1 diabetes developed by University of Virginia School of Medicine undergo two clinical trials starting early 2016.

The goal of the artificial pancreas is to eliminate the need for people with type 1 diabetes to stick their fingers multiple times daily to check their blood-sugar levels and to inject insulin manually.The artificial pancreas is designed to oversee and adjust insulin delivery as needed. At the center of the artificial pancreas platform is a reconfigured smartphone running advanced algorithms that is linked wirelessly to a blood-sugar monitor and an insulin pump, as well as a remote-monitoring site. People with the artificial pancreas can also access assistance via telemedicine.

Beneficial results from these long-term clinical trials examining how the artificial pancreas works in real-life settings could lead the U.S. Food and Drug Administration and other international regulatory groups to approve the device for use by people with type 1 diabetes, whose bodies do not produce enough insulin. The trials will conducted at nine locations in the U.S. and Europe sustained by a grant from the National Institute of Diabetes and Digestive and Kidney Diseases of the National Institutes of Health.

The first study – the International Diabetes Closed-Loop trial – will test technology developed at UVA by a research team led by Boris Kovatchev, director of the UVA Center for Diabetes Technology. That technology has been refined for clinical use by TypeZero Technologies, a startup company in Charlottesville that has licensed the UVA system. The second trial will examine a new control algorithm developed by the team of Dr. Francis Doyle III at the Harvard John A. Paulson School of Engineering and Applied Sciences to test whether it further improves control of blood-sugar levels.

Along with UVA, the artificial pancreas will be tested at eight additional sites: Harvard University, Mount Sinai School of Medicine, Mayo Clinic, University of Colorado, Stanford University, University of Montpellier in France, University of Padova in Italy and Academic Medical Center at the University of Amsterdam in The Netherlands.

SOURCE

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Multiple factors related to initial trial design may predict low patient accrual for cancer clinical trials

Reporter: Stephen J. Williams, Ph.D.

UPDATED 5/15/2019

A recently published paper in JCNI highlights results determining factors which may affect cancer trial patient accrual and the development of a predictive model of accrual issues based on those factors.

To hear a JCNI podcast on the paper click here

but below is a good posting from scienmag.com which describes their findings:

Factors predicting low patient accrual in cancer clinical trials

source: http://scienmag.com/factors-predicting-low-patient-accrual-in-cancer-clinical-trials/

Nearly one in four publicly sponsored cancer clinical trials fail to enroll enough participants to draw valid conclusions about treatments or techniques. Such trials represent a waste of scarce human and economic resources and contribute little to medical knowledge. Although many studies have investigated the perceived barriers to accrual from the patient or provider perspective, very few have taken a trial-level view and asked why certain trials are able to accrue patients faster than expected while others fail to attract even a fraction of the intended number of participants. According to a study published December 29 in the JNCI: Journal of the National Cancer Institute, a number of measurable trial characteristics are predictive of low patient accrual.

Caroline S. Bennette, M.P.H., Ph.D., of the Pharmaceutical Outcomes Research and Policy Program, University of Washington, Seattle, and colleagues from the University of Washington and the Fred Hutchinson Cancer Research Center analyzed information on 787 phase II/III clinical trials sponsored by the National Clinical Trials Network (NCTN; formerly the Cooperative Group Program) launched between 2000 and 2011. After excluding trials that closed because of toxicity or interim results, Bennette et al. found that 145 (18%) of NCTN trials closed with low accrual or were accruing at less than 50% of target accrual 3 years or more after opening.

The authors identified potential risk factors from the literature and interviews with clinical trial experts and found multiple trial-level factors that were associated with poor accrual to NCTN trials, such as increased competition for patients from currently ongoing trials, planning to enroll a higher proportion of the available patient population, and not evaluating a new investigational agent or targeted therapy. Bennette et al. then developed a multivariable prediction model of low accrual using 12 trial-level risk factors, which they reported had good agreement between predicted and observed risks of low accrual in a preliminary validation using 46 trials opened between 2012 and 2013.

The researchers conclude that “Systematically considering the overall influence of these factors could aid in the design and prioritization of future clinical trials…” and that this research provides a response to the recent directive from the Institute of Medicine to “improve selection, support, and completion of publicly funded cancer clinical trials.”

In an accompanying editorial, Derek Raghavan, M.D., Levine Cancer Institute, writes that the focus needs to be on getting more patients involved in trials, saying, “we should strive to improve trial enrollment, giving the associated potential for improved results. Whether the basis is incidental, because of case selection bias, or reflects the support available to trial patients has not been determined, but the fact remains that outcomes are better.”

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Contact info:

Article: Caroline S. Bennette, M.P.H., Ph.D., cb11@u.washington.edu

Editorial: Derek Raghavan, M.D., derek.raghavan@carolinashealthcare.org

Other investigators also feel that initial trial design is of UTMOST importance for other reasons, especially in the era of “precision” or “personalized” medicine and why the “basket trial” or one size fits all trial strategy is not always feasible.

In Why the Cancer Research Paradigm Must Transition to “N-of-1” Approach

Dr. Maurie Markman, MD gives insight into why the inital setup of a trial and the multi-center basket type of  accrual can be a problematic factor in obtaining meaningful cohorts of patients with the correct mutational spectrum.

The anticancer clinical research paradigm has rapidly evolved so that subject selection is increasingly based on the presence or absence of a particular molecular biomarker in the individual patient’s malignancy. Even where eligibility does not mandate the presence of specific biological features, tumor samples are commonly collected and an attempt is subsequently made to relate a particular outcome (eg, complete or partial objective response rate; progression-free or overall survival) to the individual cancer’s molecular characteristics.

One important result of this effort has been the recognition that there are an increasing number of patient subsets within what was previously—and incorrectly—considered a much larger homogenous patient population; for example, non–small cell lung cancer (NSCLC) versus EGFR-mutation–positive NSCLC. And, while it may still be possible to conduct phase III randomized trials involving a relatively limited percentage of patients within a large malignant entity, extensive and quite expensive effort may be required to complete this task. For example, the industry-sponsored phase III trial comparing first-line crizotinib with chemotherapy (pemetrexed plus either carboplatin or cisplatin) in ALK-rearrangement–positive NSCLC, which constitutes 3% to 5% of NSCLCs, required an international multicenter effort lasting 2.5 years to accrue the required number of research subjects.1

But what if an investigator, research team, or biotech company desired to examine the clinical utility of an antineoplastic in a patient population representing an even smaller proportion of patients with NSCLC such as in the 1% of the patient population with ROS1 abnormalities,2 or in a larger percentage of patients representing 4%-6% of patients with a less common tumor type such as ovarian cancer? How realistic is it that such a randomized trial could ever be conducted?

Further, considering the resources required to initiate and successfully conduct a multicenter international phase III registration study, it is more than likely that in the near future only the largest pharmaceutical companies will be in a position to definitively test the clinical utility of an antineoplastic in a given clinical situation.

One proposal to begin to explore the benefits of targeted antineoplastics in the setting of specific molecular abnormalities has been to develop a socalled “basket trial” where patients with different types of cancers with varying treatment histories may be permitted entry, assuming a well-defined molecular target is present within their cancer. Of interest, several pharmaceutical companies have initiated such clinical research efforts.

Yet although basket trials represent an important research advance, they may not provide the answer to the molecular complexities of cancer that many investigators believe they will. The research establishment will have to take another step toward innovation to “N-of-1” designs that truly explore the unique nature of each individual’s cancer.

Trial Illustrates Weaknesses

A recent report of the results of one multicenter basket trial focused on thoracic cancers demonstrates both the strengths but also a major fundamental weakness of the basket trial approach.3

However, the investigators were forced to conclude that despite accrual of more than 600 patients onto a study conducted at two centers over a period of approximately 2 years, “this basket trial design was not feasible for many of the arms with rare mutations.”3

They concluded that they needed a larger number of participating institutions and the ability to adapt the design for different drugs and mutations. So the question to be asked is as follows: Is the basket-type approach the only alternative to evaluate the clinical relevance of a targeted antineoplastic in the presence of a specific molecular abnormality?

Of course, the correct answer to this question is surely: No!

– See more at: http://www.onclive.com/publications/Oncology-live/2015/July-2015/Why-the-Cancer-Research-Paradigm-Must-Transition-to-N-of-1-Approach#sthash.kLGwNzi3.dpuf

The following is a video on the website ClinicalTrials.gov which is a one-stop service called EveryClinicalTrial to easily register new clinical trials and streamline the process:

 

UPDATED 5/15/2019

Another possible roadblock to patient accrual has always been the fragmentation of information concerning the availability of clinical trails and coordinating access among the various trial centers, as well as performing analytics on trial data to direct new therapeutic directions.  The NIH has attempted to circumvent this problem with the cancer trials webpage trials.gov however going through the vast number of trials, patient accrual requirements, and finding contact information is a daunting task.  However certain clinical trial marketplaces are now being developed which may ease access problems to clinical trials as well as data analytic issues, as highlighted by the Scientist.com article below:

Scientist.com Launches Trial Insights, A Transformative Clinical Trials Data Analytics Solution

The world’s largest online marketplace rolls out first original service, empowering researchers with on demand insights into clinical trials to help drive therapeutic decisions

SAN DIEGO–(BUSINESS WIRE)–Scientist.com, the online marketplace for outsourced research, announced today the launch of Trial Insights, a digital reporting solution that simplifies data produced through clinical trial, biomarker and medical diagnostic studies into an intuitive and user-friendly dashboard. The first of its kind, Trial Insights curates publicly available data nightly from information hubs such as clinicaltrials.gov and customizes it to fit a researcher or research organization’s specific project needs.

Trial Insights, new clinical trial reporting solution, allows researchers to keep track of the evolving landscape of drugs, diseases, sponsors, investigators and medical devices important to their work.

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“Trial Insights offers researchers an easy way to navigate the complexity of clinical trials information,” said Ron Ranauro, Founder of Incite Advisors. “Since Trial Insights’ content is digitally curated, researchers can continuously keep track of the evolving landscape of drugs, diseases, sponsors, investigators and medical devices important to their work.”

As the velocity, variety and veracity of data available on sites like clinicaltrials.gov continues to increase, the ability to curate it becomes more valuable to different audiences. With the advancement of personalized medicine, it is important to make the data accessible to the health care and patient communities. Information found on the Trial Insights platform can help guide decision making across the pharmaceutical, biotechnology and contract research organization industries as clinical trial data is a primary information source for competitive intelligence, research planning and clinical study planning.

“We are extremely excited to launch the first Scientist.com exclusive, original service offering to our clients in the life sciences,” said Mark Herbert, Scientist.com Chief Business Officer. “Our goal at Scientist.com is to help cure all diseases by 2050, and we believe solutions like Trial Insights, which greatly simplifies access to and reporting of clinical trial data, will get us one step closer to reaching that goal.”

source: https://www.businesswire.com/news/home/20190416005362/en/Scientist.com-Launches-Trial-Insights-Transformative-Clinical-Trials?utm_source=TrialIO+List

 

Other article on this Open Access Journal on Cancer Clinical Trial Design include:

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Muscular dystrophy has deficient stem cell dystrophin

Larry H. Bernstein, MD, FCAP, Curator

LPBI

 

Dystrophin Deficient Stem Cell Pathology

 

Muscular Dystrophy is a Stem Cell-Based Disease

Because DMD results from mutations in the dystrophin gene, the vast majority of muscular dystrophy research was based on a simple model in which the Dystrophin protein played a structural role in the structural integrity of muscle fibers. Abnormal versions of the Dystrophin protein caused the muscle fibers to become damaged and die as a result of contraction.  Dystrophin anchors the cytoskeleton of the muscle fibers, which are essential for muscle contraction, to the muscle cell membrane, and then to the extracellular matrix outside the cell that serves as a foundation upon which the muscle cells are built.

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However in this current study, Rudnicki and his team discovered that muscle stem cells also express the dystrophin protein. This is a revelation because Dystrophin was thought to be protein that ONLY appeared in mature muscle. However, in this study, it became exceedingly clear that in the absence of Dystrophin, muscle stem cells generated ten-fold fewer muscle precursor cells, and, consequently, far fewer functional muscle fibers. Dystrophin is also a component of a signal transduction pathway that allows muscle stem cells to properly ascertain if they need to replace dead or dying muscle.  Muscle stem cells repair the muscle in response to injury or exercise by dividing to generate precursor cells that differentiate into muscle fibers.

Even though Rudnicki used mice as a model system in these experiments, the Dystrophin protein is highly conserved in most vertebrate animals. Therefore, it is highly likely that these results will also apply to human muscle stem cells.

Gene therapy experiments and trials are in progress and even show some promise, but Rudnicki’s work tells us that gene therapy approaches must target muscle stem cells as well as muscle fibers if they are to work properly.

“We’re already looking at approaches to correct this problem in muscle stem cells,” said Dr. Rudnicki.

This paper has received high praise from the likes of Ronald Worton, who was one of the co-discovers of the dystrophin gene with Louis Kunkel in 1987.

Early pathogenesis of Duchenne muscular dystrophy modelled in patient-derived human induced pluripotent stem cells

Emi Shoji, Hidetoshi Sakurai, Tokiko Nishino, Tatsutoshi Nakahata, Toshio Heike, Tomonari Awaya, Nobuharu Fujii, Yasuko Manabe, Masafumi Matsuo & Atsuko Sehara-Fujisawa

Scientific Reports 5, Article number: 12831 (2015)   http://dx.doi.org:/10.1038/srep12831

Duchenne muscular dystrophy (DMD) is a progressive and fatal muscle degenerating disease caused by a dystrophin deficiency. Effective suppression of the primary pathology observed in DMD is critical for treatment. Patient-derived human induced pluripotent stem cells (hiPSCs) are a promising tool for drug discovery. Here, we report an in vitro evaluation system for a DMD therapy using hiPSCs that recapitulate the primary pathology and can be used for DMD drug screening. Skeletal myotubes generated from hiPSCs are intact, which allows them to be used to model the initial pathology of DMD in vitro. Induced control and DMD myotubes were morphologically and physiologically comparable. However, electric stimulation of these myotubes for in vitro contraction caused pronounced calcium ion (Ca2+) influx only in DMD myocytes. Restoration of dystrophin by the exon-skipping technique suppressed this Ca2+ overflow and reduced the secretion of creatine kinase (CK) in DMD myotubes. These results suggest that the early pathogenesis of DMD can be effectively modelled in skeletal myotubes induced from patient-derived iPSCs, thereby enabling the development and evaluation of novel drugs.

Duchenne muscular dystrophy (DMD) is characterised by progressive muscle atrophy and weakness that eventually leads to ambulatory and respiratory deficiency from early childhood1. It is an X-linked recessive inherited disease with a relatively high frequency of 1 in 3500 males1,2.DMD, which is responsible for DMD, encodes 79 exons and produces dystrophin, which is one of the largest known cytoskeletal structural proteins3. Most DMD patients have various types of deletions or mutations in DMD that create premature terminations, resulting in a loss of protein expression4. Several promising approaches could be used to treat this devastating disease, such as mutation-specific drug exon-skipping5,6, cell therapy7, and gene therapy1,2.

Myoblasts from patients are the most common cell sources for assessing the disease phenotypes of DMD11,12. …Previous reports have shown that muscle cell differentiation from DMD patient myoblasts is delayed and that these cells have poor proliferation capacity compared to those of healthy individuals11,12. Our study revealed that control and DMD myoblasts obtained by activating tetracycline-dependent MyoD transfected into iPS cells (iPStet-MyoD cells) have comparable growth and differentiation potential and can produce a large number of intact and homogeneous myotubes repeatedly.

The pathogenesis of DMD is initiated and progresses with muscle contraction. The degree of muscle cell damage at the early stage of DMD can be evaluated by measuring the leakage of creatine kinase (CK) into the extracellular space15. Excess calcium ion (Ca2+) influx into skeletal muscle cells, together with increased susceptibility to plasma membrane injury, is regarded as the initial trigger of muscle damage in DMD19,20,21,22,23,24. Targeting these early pathogenic events is considered essential for developing therapeutics for DMD.

In this study, we established a novel evaluation system to analyse the cellular basis of early DMD pathogenesis by comparing DMD myotubes with the same clone but with truncated dystrophin-expressing DMD myotubes, using the exon-skipping technique. We demonstrated through in vitro contraction that excessive Ca2+ influx is one of the earliest events to occur in intact dystrophin-deficient muscle leading to extracellular leakage of CK in DMD myotubes.

Generation of tetracycline-inducible MyoD-transfected DMD patient-derived iPSCs (iPStet-MyoD cells)

Figure 1: Generation and characterization of control and DMD patient-derived Tet-MyoD-transfected hiPS cells.   Full size image

Morphologically and physiologically comparable intact myotubes differentiated from control and DMD-derived hiPSCs

Figure 2: Morphologically and physiologically comparable skeletal muscle cells differentiated from Control-iPStet-MyoD and DMD-iPStet-MyoD.   Full size image

Exon-skipping with AO88 restored expression of Dystrophin in DMD myotubes differentiated from DMD-iPStet-MyoD cells

Figure 3: Restoration of dystrophin protein expression by AO88.   Full size image

Restored dystrophin expression attenuates Ca2+ overflow in DMD-Myocytes

Figure 4: Restored expression of dystrophin diminishes Ca2+ influx in DMD muscle in response to electric stimulation.   Full size image


Ca2+ influx provokes skeletal muscle cellular damage in DMD muscle

Figure 5: Ca2+ influx induces prominent skeletal muscle cellular damage in DMD-Myocytes.   Full size image

Skeletal muscle differentiation in myoblasts from DMD patients is generally delayed compared to that in healthy individuals11,36,37.  Our differentiation system successfully induced the formation of myotubes from DMD patients, and the myotubes displayed analogous morphology and maturity compared with control myotubes (Fig. 2a–c).  Comparing myotubes generated from patient-derived iPS cells with those derived from the same DMD clones but expressing dystrophin by application of the exon-skipping technique enabled us to demonstrate the primary cellular phenotypes in skeletal muscle solely resulting from the loss of the dystrophin protein (Fig. 4b).  Our results demonstrate that truncated but functional dystrophin protein expression improved the cellular phenotype of DMD myotubes.

In DMD, the lack of dystrophin induces an excess influx of Ca2+ , leading to pathological dystrophic changes22. We consistently observed excess Ca2+ influx in DMD-Myocytes compared to Control-Myocytes (Supplementary Figure S3a and S3b) in response to electric stimulation. TRP channels, which are mechanical stimuli-activated Ca2+ channels40that are expressed in skeletal muscle cells41, can account for this pathogenic Ca2+ influx…

In conclusion, our study revealed that the absence of dystrophin protein induces skeletal muscle damage by allowing excess Ca2+ influx in DMD myotubes. Our experimental system recapitulated the early phase of DMD pathology as demonstrated by visualisation and quantification of Ca2+ influx using intact myotubes differentiated from hiPS cells.  This evaluation system significantly expands prospective applications with regard to assessing the effectiveness of exon-skipping drugs and also enables the discovery of drugs that regulate the initial events in DMD.

Duchenne muscular dystrophy affects stem cells, University of Ottawa study finds  

New treatments could one day be available for the most common form of muscular dystrophy after a study suggests the debilitating genetic disease affects the stem cells that produce healthy muscle fibres.

The findings are based on research from the University of Ottawa and The Ottawa Hospital, published Monday in the journal Nature Medicine.

For nearly two decades, doctors had thought the muscular weakness that is the hallmark of the disease was due to problems with human muscle fibers, said Dr. Michael Rudnicki, the study’s senior author.

The new research shows the specific protein characterized by its absence in Duchenne muscular dystrophy normally exists in stem cells.

Dystrophin protein found in stem cells

“The prevailing notion was that the protein that’s missing in Duchenne muscular dystrophy — a protein called dystrophin — was not involved at all in the function of the stem cells.”

http://soundcloud.com/cbcottawa1

When the genetic mutations caused by Duchenne muscular dystrophy inhibit the production of dystrophin in stem cells, those stem cells produce significantly fewer precursor cells — and thus fewer properly functioning muscle fibres.  Further, stem cells need dystrophin to sense their environment to figure out if they need to divide to produce more stem cells or perform muscle repair work.

Genetic repair might treat Duchenne muscular dystrophy

July 25, 2011|By Thomas H. Maugh II, Los Angeles Times

A genetic technique that allows the body to work around a crucial mutation that causes Duchenne muscular dystrophy increased the mass and function of muscles in a small group of patients with the devastating disease, paving the way for larger clinical trials of the drug. The study in a handful of boys age 5 to 15 showed that patients receiving the highest level of the drug, called AVI-4658 or eteplirsen, had a significant increase in production of a missing protein and increases in muscle fibers. The study demonstrated that the drug is safe in the short term. Results were reported Sunday in the journal Lancet.

Duchenne muscular dystrophy affects about one in every 3,500 males worldwide. It is caused by any one of several different mutations that affect production of a protein called dystrophin, which is important for the production and maintenance of muscle fibers. Affected patients become unable to walk and must use a wheelchair by age 8 to 12. Deterioration continues through their teens and 20s, and the condition typically proves fatal as muscle failure impairs their ability to breathe.

This study is designed to assess the efficacy, safety, tolerability, and pharmacokinetics (PK) of AVI-4658 (eteplirsen) in both 50.0 mg/kg and 30.0 mg/kg doses administered over 24 weeks in subjects diagnosed with Duchenne muscular dystrophy (DMD).

 

Condition Intervention Phase
Duchenne Muscular Dystrophy Drug: AVI-4658 (Eteplirsen)
Other: Placebo
Phase 2

 

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Safety/Efficacy Study
Intervention Model: Parallel Assignment
Masking: Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor)
Primary Purpose: Treatment
Official Title: A Randomized, Double-Blind, Placebo-Controlled, Multiple Dose Efficacy, Safety, Tolerability and Pharmacokinetics Study of AVI-4658(Eteplirsen),in the Treatment of Ambulant Subjects With Duchenne Muscular Dystrophy
Resource links provided by NLM:
Dystrophin expression in muscle stem cells regulates their polarity and asymmetric division

Nature Medicine(2015)   http://dx.doi.org:/10.1038/nm.3990

Dystrophin is expressed in differentiated myofibers, in which it is required for sarcolemmal integrity, and loss-of-function mutations in the gene that encodes it result in Duchenne muscular dystrophy (DMD), a disease characterized by progressive and severe skeletal muscle degeneration. Here we found that dystrophin is also highly expressed in activated muscle stem cells (also known as satellite cells), in which it associates with the serine-threonine kinase Mark2 (also known as Par1b), an important regulator of cell polarity. In the absence of dystrophin, expression of Mark2 protein is downregulated, resulting in the inability to localize the cell polarity regulator Pard3 to the opposite side of the cell. Consequently, the number of asymmetric divisions is strikingly reduced in dystrophin-deficient satellite cells, which also display a loss of polarity, abnormal division patterns (including centrosome amplification), impaired mitotic spindle orientation and prolonged cell divisions. Altogether, these intrinsic defects strongly reduce the generation of myogenic progenitors that are needed for proper muscle regeneration. Therefore, we conclude that dystrophin has an essential role in the regulation of satellite cell polarity and asymmetric division. Our findings indicate that muscle wasting in DMD not only is caused by myofiber fragility, but also is exacerbated by impaired regeneration owing to intrinsic satellite cell dysfunction.

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PD1 Inhibitor atezolizumab may show promise in bladder cancer in patients with high PDL1 expression

Reporter: Stephen J Williams

Updated 4/15/2016

Promising Immunotherapy Agents on Horizon in Bladder Cancer

Reported from OncLive

Virginia Powers, PhD

Published Online: Monday, November 16, 2015 at http://www.onclive.com/web-exclusives/promising-immunotherapy-agents-on-horizon-in-bladder-cancer

 

thompson

Thomas Powles, MD

The dramatic and often practice-changing findings demonstrated by trials of immunotherapies in melanoma and lung cancer may soon be reflected in the treatment of bladder cancer, according to a summary of ongoing studies1 presented at the 7th European Multidisciplinary Meeting on Urological Cancers (EMUC).

“Immune therapy is a promising new treatment in transitional cell carcinoma (TCC) of the bladder,” said Thomas Powles, MD, medical oncologist, director of St Bartholomew’s Cancer Centre, London. “Until recently, bladder cancer research has been somehow left behind.”

Powles underscored that immune checkpoint inhibitors are active in urothelial bladder cancer (UBC) and provided an overview of the emergence of immune therapy in bladder cancer that focused on agents targeting the immune checkpoint axis, especially the programed death receptor (PD1) and its ligand (PD-L1).

“Each drug has a unique companion diagnostic but the strongest data so far are seen with blocking PD-L1 and atezolizumab,” he said.

The confirmed overall response rate (ORR) by RECIST to atezolizumab are associated with PD-L1 expression levels in the tumor. In a phase I trial of second line atezolizumab (MPDL3280A) in TCC, a response was demonstrated in patients that had previously showed only a 10% response rate to chemotherapy. The ORRs were 43% for patients with tumors expressing high levels of PD-L1 (IHC 2/3) compared to 11% in patients with tumors having low expression (IHC 0 or 1).2

PD-L1 expression on the immune cells (IC) infiltrating the tumor has also been shown to be associated with response. The PD-L1 expression on ICs was evaluated as low, medium, and high in approximately one-third each of 311 patients with locally-advanced or metastatic urothelial carcinoma (mUC) participating in the phase II IMvigor 210 trial, which corresponded to an ORR with atezolizumab of 9%, 10%, and 27% in the respective expression groups.

Overall survival (OS) at a median follow-up of 7 months (range, 0-11) also correlated with expression levels and was 6.7 months in low (IC0/1), not reached in high (IC2/3) expressing patients, and 7.9 months in overall population. However, no difference was seen in progression-free survival (PFS) according to expression levels; median PFS was 2.1 months in the overall population and in patients having both low (IC0/1) and high (IV2/3) expression levels, respectively. These data were emphasized as early response data that are expected to mature in further analyses.3

Powles commented that his team is beginning a phase III randomized trial of atezolizumab in 767 patients with locally-advanced UBC who were also chemotherapy-resistant following 1 to 2 prior lines of a platinum-based regimen. Patients have been stratified by chemotherapy regimen, PD-L1 expression, IHC status, risk factors, and the presence of liver metastasis. The primary endpoint is OS and secondary endpoints include ORR, PFS, and duration of response (DoR), safety, and tolerability. Other objectives include disease control rate and potential biomarkers.

“PD-L1 expression appears important but we need to find other biomarkers,” he remarked.

Powles moved on to discuss the KEYNOTE-012 phase Ib trial of pembrolizumab, an anti-PD1 antibody that blocks interaction with both PD-L1 and PD-L2. In KEYNOTE, pembrolizumab demonstrated anti-tumor activity in patients with recurrent or metastatic PD-L1–positive UBC in 64% of patients experiencing a decrease in target lesions from baseline.4

Combination and adjuvant studies are ongoing, according to Powles. A trial of atezolizumab as adjuvant therapy versus placebo is underway in patients with TCC whose tumors express PD-L1. The trial has a primary endpoint of disease-free survival (DFS).

“Next-generation combination therapy with nivolumab plus ipilimumab is a common sense approach that was tested in advanced melanoma and is now being evaluated in the Danube trial,” Powles said.

Nivolumab, a PD-1 blocking antibody, and ipilimumab, which blocks CTLA-4, will be evaluated in Danube, a randomized phase III study that will enroll 800 patients with untreated metastatic TCC. The endpoints are PFS and OS. Patients are required to have available tissue for PD-L1 testing and no contraindications for immune therapy.

The rationale for the combination was demonstrated in melanoma, where confirmed objective responses were seen in 61% of patients receiving nivolumab plus ipilimumab versus 11% in patients receiving ipilimumab and placebo (P <0.001). Complete responses were reported in 16 patients (22%) with combination compared to no patients receiving ipilimumab monotherapy.5

“It looks like checkpoint inhibition works particularly well in node positive patients; in the future we can see treatment with first-line immunotherapeutic agents,” said Powles.

“We hope that immune therapy will identify a subset of patients who get long-term benefits from immune therapy,” Powles said. “The future looks bright for immunotherapy in bladder cancer.”

References

  1. Powles T. Update on systemic treatments in bladder cancer. Presented at: 7th European Multidisciplinary Meeting on Urological Cancers (EMUC), Barcelona, Spain, November 12–15, 2015.
  2. Powles T, Eder JP, Fine GD, et al. MPDL3280A (anti-PD-L1) treatment leads to clinical activity in metastatic bladder cancer. Nature. 2014;515(7528):558-562.
  3. Rosenberg J, Petrylak D, Abidoye O, et al. Atezolizumab in patients (pts) with locally-advanced or metastatic urothelial carcinoma (mUC): Results from a pivotal multicenter phase II study (IMvigor 210). Presented at: 2015 European Cancer Congress; September 25-29; Vienna, Austria. Abstract 21LBA.
  4. Plimack ER, Bellmunt J, Gupta S, et al. Pembrolizumab (MK-3475) for advanced urothelial cancer: Updated results and biomarker analysis from KEYNOTE-012. J Clin Oncol 33, 2015 (suppl; abstr 4502).
  5. Larkin J, Chiarion-Sileni V, Gonzalez R, et al. Combined nivolumab and ipilimumab or monotherapy in untreated melanoma. N Engl J Med. 2015; 373:23-34.

– See more at: http://www.onclive.com/web-exclusives/promising-immunotherapy-agents-on-horizon-in-bladder-cancer#sthash.c63jReGo.dpuf

Speedy review for Merck’s Keytruda in head and neck cancer

DAILY NEWS | APRIL 14, 2016

SELINA MCKEE

Speedy review for Merck's Keytruda in head and neck cancer

US regulators have agreed to undertake a speedy review of Merck & Co’s application to market immunotherapy Keytruda for the treatment of certain patients with head and neck cancer, it third potential indication in the country.

 

The company is targeting the drug towards patients with recurrent or metastatic head and neck squamous cell carcinoma (HNSCC) with disease progression on or after platinum-containing chemotherapy.

 

“We are encouraged by the data emerging from our program in this type of cancer, and welcome today’s news as this is an important step toward making Keytruda (pembrolizumab) available to these patients,” said Roger Dansey, senior vice president and therapeutic area head, oncology late-stage development, Merck Research Laboratories.

 

The US Food and Drug Administration has set an action date for Keytruda – an anti-PD-1 therapy dosed as a single agent intravenously every three weeks – of August 9.

 

Keytruda is a humanised monoclonal antibody that boosts the ability of the body’s immune system to help detect and fight tumour cells. The drug has already racked up approvals in melanoma and lung cancer in the US.

Read more at: http://www.pharmatimes.com/Article/16-04-14/Speedy_review_for_Merck_s_Keytruda_in_head_and_neck_cancer.aspx#ixzz45uMyaCdc
Follow us: @PharmaTimes on Twitter

 

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FDA Cellular & Gene Therapy Guidances: Implications for CRSPR/Cas9 Trials

Reporter: Stephen J. Williams, PhD

The recent announcement by Editas CEO Katrine Bosley to pursue a CRSPR/Cas9 gene therapy trial to correct defects in an yet to be disclosed gene to treat one form of a rare eye disease called Leber congenital amaurosis (multiple mutant genes have been linked to the disease) have put an interesting emphasis on the need for a regulatory framework to initiate these trials. Indeed at the 2015 EmTechMIT Conference Editas CEO Katrine Bosley had mentioned this particular issue: the need for discourse with FDA and regulatory bodies to establish guidelines for design of clinical trials using the CRSPR gene editing tool.

See the LIVE NOTES from Editas CEO Katrine Bosley on using CRSPR as a gene therapy from the 2015 EmTechMIT Conference at https://pharmaceuticalintelligence.com/2015/11/03/live-1132015-130pm-the-15th-annual-emtech-mit-mit-media-lab-top-10-breakthrough-technologies-2015-innovators-under-35/

To this effect, I have listed below, the multiple FDA Guidance Documents surrounding gene therapy to show that, in the past year, the FDA has shown great commitment to devise a regulatory framework for this therapeutic area.

Cellular & Gene Therapy Guidance Documents

Withdrawn Guidance Documents

Three other posts on this site goes into detail into three of the above-mentioned Guidance Documents

FDA Guidance on Use of Xenotransplanted Products in Human: Implications in 3D Printing

New FDA Draft Guidance On Homologous Use of Human Cells, Tissues, and Cellular and Tissue-Based Products – Implications for 3D BioPrinting of Regenerative Tissue

FDA Guidance Documents Update Nov. 2015 on Devices, Animal Studies, Gene Therapy, Liposomes

 

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FDA Guidance Documents Update

Reporter: Stephen J. Williams, Ph.D.

You are subscribed to FDA Guidance Documents for U.S. Food & Drug Administration (FDA).

This information has recently been updated and is now available.

Recently posted guidance documents

10/14/15: General Considerations for Animal Studies for Medical Devices – Draft Guidance for Industry and Food and Drug Administration Staff

10/14/15: Recommendations for Microbial Vectors Used for Gene Therapy; Draft Guidance for Industry

10/15/15: Draft PDEs for Triethylamine and for Methylisobutylketone

10/15/15: ICH Q3C Maintenance Procedures for the Guidance for Industry Q3C Impurities: Residual Solvents

10/19/15: CVM GFI #229 – Evaluating the Effectiveness of New Animal Drugs for the Reduction of Pathogenic Shiga Toxin-Producing E. coli in Cattle

10/21/15: Selection of the Appropriate Package Type Terms and Recommendations for Labeling Injectable Medical Products Packaged in Multiple-Dose, Single-Dose, and Single-Patient-Use Containers for Human Use

10/21/15: Manufacturing Site Change Supplements: Content and Submission – Draft Guidance for Industry and Food and Drug Administration Staff

10/26/15: Interim Policy on Compounding Using Bulk Drug Substances Under Section 503A of the Federal Food, Drug, and Cosmetic Act Guidance for Industry

10/26/15: Interim Policy on Compounding Using Bulk Drug Substances Under Section 503B of the Federal Food, Drug, and Cosmetic Act

10/26/15: Pharmacy Compounding of Human Drug Products Under Section 503A of the Federal Food, Drug, and Cosmetic Act Guidance

10/27/15: Nonclinical Safety Evaluation of Reformulated Drug Products and Products Intended for Administration by an Alternate Route

10/27/15: Product Development Under the Animal Rule

10/28/15: DSCSA Implementation: Product Tracing Requirements for Dispensers — Compliance Policy (Revised) Guidance for Industry

10/29/15: Liposome Drug Products: Chemistry, Manufacturing, and Controls; Human Pharmacokinetics and Bioavailability; and Labeling Documentation

Guidance Document Search

•    Search all FDA official guidance documents and other regulatory guidance

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A Curated History of the Science Behind the Ovarian Cancer β-Blocker Trial

Curator: Stephen J. Williams, Ph.D.

 

This post is a follow-up on the two reports found in this Open Access Journal

https://pharmaceuticalintelligence.com/2015/09/16/ovarian-cancer-survival-increased-5-months-overall-with-beta-blockers-study-the-speaker/

AND

https://pharmaceuticalintelligence.com/2013/04/08/beta-blockers-help-in-better-survival-in-ovarian-cancer/

in order to explain some of the background which went into the development of these reports.

A recent paper by Anil Sood’s group at MD Anderson in Journal of Cancer: Clinical impact of selective and nonselective beta-blockers on survival in patients with ovarian cancer describes a retrospective pathologic evaluation of ovaries from patients taking various beta blockers for currently approved indications.

The history of this finding is quite interesting and, as I remember in a talk given by Dr. Sood in mid-2000’s, a microarray conducted by his lab had showed overexpression of the β2-AR (β2 adrenergic receptor in ovarian cancer cells relative to normal epithelium. At the time it appeared an interesting result however most of the cancer (and ovarian cancer) field were concentrating on the tyrosine kinase signaling pathways as potential therapeutic targets, as much promising translational research in this area was in focus at the time. As a result of this finding and noticing that sustained β-adrenergic stimulation can promote ovarian cancer cell growth (Sood, 2006), Dr. Sood’s group have been studying the effects of β-adrenergic signaling om ovarian cancer. In addition it has been shown that propanalol can block VEGF signaling and norepinephrine increased MMP2 and MMP9 expression, an effect mediated by the β2-AR.

The above re-post of a Scoop-IT describes promising results of a clinical trial for use of selective beta blockers in ovarian cancer.   As to date, there have been many clinical trials initiated in ovarian cancer and most have not met with success for example the following posts:

Good and Bad News Reported for Ovarian Cancer Therapy

a follow-up curation on the problems encountered with the PARP-inhibitor olaparib

enough is enough: Treat ‘Each Patient as an Individual’

which contains an interview with Dr. Maurie Markman (Vice President, Patient Oncology Services, and National Director for Medical Oncology, Cancer Treatment Centers of America) and Dr. Kathy D. Miller, Indiana University School of Medicine) and discusses how each patient’s ovarian cancer is genetically unique and needs to be treated as such

Therefore the mainstay therapy is still carboplatin plus a taxane (Taxotere, Abraxane). The results of this clinical trial show a 5 month improvement in survival, which for a deadly disease like ovarian cancer is a significant improvement.

First below is a SUMMARY of the paper’s methodology and findings.

Methods:

  • Four participating institutions collected retrospective patient data and pathology reports from 1425 patients diagnosed with epithelial ovarian cancer (EOC)
  • Medical records were evaluated for use of both selective and nonselective β-blockers
  • β-blockers were used for various indications however most common indication was treatment for hypertension (71% had used β1 selective blockers while rest of patients taking β blockers were given nonselective blockers for a host of other indications)
  • most patients had stage III/IV disease and in general older (median age 63 years)
  • The authors looked at overall survival (OS) however progression free survival PFS) was not calculated

Results:

  • Hypertension was associated with decreased survival (40.1 monts versus 47.4 months for normotensive patients)
  • Overall Survival for patients on any β blockers was 47.8 months versus 42.0 months for nonusers
  • Patients receiving nonselective β blockers has an OS of 94.9 months versus 38 months for EOC patients receiving β1-selective blockers
  • No effect of diabetes mellitus on survival

Authors Note on Limitations of Study:

  • Retrospective in nature
  • Lack of documentation of dosage, trade-name and duration of β-blocker use
  • Important to stratify patients on selectivity of β-blocker since Eskander et. al. found no difference of Progression Free Survival and non-selective β-blocker
  • Several β adrenergic receptor polymorphisms may exist and no downstream biomarker evaluated to determine effect on signaling; could it be a noncanonical effect?

The goal of this brief, added curation is to paint a historical picture, and highlight the scientific findings which led up to the rationale behind this clinical trial.

How the βeta Adrenergic Receptor (βAR) Became a Target for Ovarian Cancer

.

A. βAR and its signaling over-expressed in ovarian cancer

Role of mitogen-activated protein kinase/extracellular signal-regulated kinase cascade in gonadotropin-releasing hormone-induced growth inhibition of a human ovarian cancer cell line.

Kimura A, Ohmichi M, Kurachi H, Ikegami H, Hayakawa J, Tasaka K, Kanda Y, Nishio Y, Jikihara H, Matsuura N, Murata Y.

Cancer Res. 1999 Oct 15;59(20):5133-42.

Cyclic AMP induces integrin-mediated cell adhesion through Epac and Rap1 upon stimulation of the beta 2-adrenergic receptor.

Rangarajan S, Enserink JM, Kuiperij HB, de Rooij J, Price LS, Schwede F, Bos JL.

J Cell Biol. 2003 Feb 17;160(4):487-93. Epub 2003 Feb 10.

B. Mechanistic Link Between Chronic Stress From Excess Adrenergic Stimulation and Angiogenesis and Metastasis

Stress-related mediators stimulate vascular endothelial growth factor secretion by two ovarian cancer cell lines.

Lutgendorf SK, Cole S, Costanzo E, Bradley S, Coffin J, Jabbari S, Rainwater K, Ritchie JM, Yang M, Sood AK.

Clin Cancer Res. 2003 Oct 1;9(12):4514-21.PMID:

Norepinephrine up-regulates the expression of vascular endothelial growth factor, matrix metalloproteinase (MMP)-2, and MMP-9 in nasopharyngeal carcinoma tumor cells.

Yang EV, Sood AK, Chen M, Li Y, Eubank TD, Marsh CB, Jewell S, Flavahan NA, Morrison C, Yeh PE, Lemeshow S, Glaser R.

Cancer Res. 2006 Nov 1;66(21):10357-64.

VEGF is differentially regulated in multiple myeloma-derived cell lines by norepinephrine.

Yang EV, Donovan EL, Benson DM, Glaser R.

Brain Behav Immun. 2008 Mar;22(3):318-23. Epub 2007 Nov 5.

Chronic stress promotes tumor growth and angiogenesis in a mouse model of ovarian carcinoma.

Thaker PH, Han LY, Kamat AA, Arevalo JM, Takahashi R, Lu C, Jennings NB, Armaiz-Pena G, Bankson JA, Ravoori M, Merritt WM, Lin YG, Mangala LS, Kim TJ, Coleman RL, Landen CN, Li Y, Felix E, Sanguino AM, Newman RA, Lloyd M, Gershenson DM, Kundra V, Lopez-Berestein G, Lutgendorf SK, Cole SW, Sood AK.

Nat Med. 2006 Aug;12(8):939-44. Epub 2006 Jul 23.

Norepinephrine up-regulates the expression of vascular endothelial growth factor, matrix metalloproteinase (MMP)-2, and MMP-9 in nasopharyngeal carcinoma tumor cells.

Yang EV, Sood AK, Chen M, Li Y, Eubank TD, Marsh CB, Jewell S, Flavahan NA, Morrison C, Yeh PE, Lemeshow S, Glaser R.

Cancer Res. 2006 Nov 1;66(21):10357-64.

C. In Vivo Studies Confirm In Vitro Findings That Chronic Stress Via Adrenergic overstimulation Increases Ovarian Cancer Growth

Chronic stress promotes tumor growth and angiogenesis in a mouse model of ovarian carcinoma.

Thaker PH, Han LY, Kamat AA, Arevalo JM, Takahashi R, Lu C, Jennings NB, Armaiz-Pena G, Bankson JA, Ravoori M, Merritt WM, Lin YG, Mangala LS, Kim TJ, Coleman RL, Landen CN, Li Y, Felix E, Sanguino AM, Newman RA, Lloyd M, Gershenson DM, Kundra V, Lopez-Berestein G, Lutgendorf SK, Cole SW, Sood AK.

Nat Med. 2006 Aug;12(8):939-44. Epub 2006 Jul 23.

Stress hormone-mediated invasion of ovarian cancer cells.

Sood AK, Bhatty R, Kamat AA, Landen CN, Han L, Thaker PH, Li Y, Gershenson DM, Lutgendorf S, Cole SW.

Clin Cancer Res. 2006 Jan 15;12(2):369-75.

The neuroendocrine impact of chronic stress on cancer.

Thaker PH, Lutgendorf SK, Sood AK.

Cell Cycle. 2007 Feb 15;6(4):430-3. Epub 2007 Feb 9. Review.

Surgical stress promotes tumor growth in ovarian carcinoma.

Lee JW, Shahzad MM, Lin YG, Armaiz-Pena G, Mangala LS, Han HD, Kim HS, Nam EJ, Jennings NB, Halder J, Nick AM, Stone RL, Lu C, Lutgendorf SK, Cole SW, Lokshin AE, Sood AK.

Clin Cancer Res. 2009 Apr 15;15(8):2695-702. doi: 10.1158/1078-0432.CCR-08-2966. Epub 2009 Apr 7.

Sood group wanted to mimic the surgical stress after laparoscopic surgery to see if surgical stress would promote the growth of micrometasteses remaining after surgical tumor removal. Propranolol completely blocked the effects of surgical stress on tumor growth, indicating a critical role for beta-adrenergic receptor signaling in mediating the effects of surgical stress on tumor growth. In the HeyA8 and SKOV3ip1 models, surgery significantly increased microvessel density (CD31) and vascular endothelial growth factor expression, which were blocked by propranolol treatment. Tumor growth after surgery was decreased in a mouse null for βAR. Levels of cytokines G-CSF, IL-1a, IL-6, and IL-15were increased after surgery

Stress effects on FosB- and interleukin-8 (IL8)-driven ovarian cancer growth and metastasis J Biol Chem. 2010 Nov 12;285(46):35462-70. doi: 10.1074/jbc.M110.109579. Epub 2010 Sep 8.

Shahzad MM1, Arevalo JM, Armaiz-Pena GN, Lu C, Stone RL, Moreno-Smith M, Nishimura M, Lee JW, Jennings NB, Bottsford-Miller J, Vivas-Mejia P, Lutgendorf SK, Lopez-Berestein G, Bar-Eli M, Cole SW, Sood AK.

Free PMC Article

Abstract

A growing number of studies indicate that chronic stress can accelerate tumor growth due to sustained sympathetic nervous system activation. Our recent findings suggest that chronic stress is associated with increased IL8 levels. Here, we examined the molecular and biological significance of IL8 in stress-induced tumor growth. Norepinephrine (NE) treatment of ovarian cancer cells resulted in a 250-300% increase in IL8 protein and 240-320% increase in its mRNA levels. Epinephrine treatment resulted in similar increases. Moreover, NE treatment resulted in a 3.5-4-fold increase in IL8 promoter activity. These effects were blocked by propranolol. Promoter deletion analyses suggested that AP1 transcription factors might mediate catecholamine-stimulated up-regulation of IL8. siRNA inhibition studies identified FosB as the pivotal component responsible for IL8 regulation by NE. In vivo chronic stress resulted in increased tumor growth (by 221 and 235%; p < 0.01) in orthotopic xenograft models involving SKOV3ip1 and HeyA8 ovarian carcinoma cells. This enhanced tumor growth was completely blocked by IL8 or FosB gene silencing using 1,2-dioleoyl-sn-glycero-3-phosphatidylcholine nanoliposomes. IL8 and FosB silencing reduced microvessel density (based on CD31 staining) by 2.5- and 3.5-fold, respectively (p < 0.001). Our findings indicate that neurobehavioral stress leads to FosB-driven increases in IL8, which is associated with increased tumor growth and metastases. These findings may have implications for ovarian cancer management.

Dopamine blocks stress-mediated ovarian carcinoma growth.

Moreno-Smith M, Lu C, Shahzad MM, Pena GN, Allen JK, Stone RL, Mangala LS, Han HD, Kim HS, Farley D, Berestein GL, Cole SW, Lutgendorf SK, Sood AK.

Clin Cancer Res. 2011 Jun 1;17(11):3649-59. doi: 10.1158/1078-0432.CCR-10-2441. Epub 2011 Apr 29.

D. Additional mechanisms iincluding JAK/STAT modulation, prostaglandin synthesis, AKT, and Slug implicated in Stress (norepinephrine) induced increase in Ovarian Tumor Growth

Sustained adrenergic signaling leads to increased metastasis in ovarian cancer via increased PGE2 synthesis.

Nagaraja AS, Dorniak PL, Sadaoui NC, Kang Y, Lin T, Armaiz-Pena G, Wu SY, Rupaimoole R, Allen JK, Gharpure KM, Pradeep S, Zand B, Previs RA, Hansen JM, Ivan C, Rodriguez-Aguayo C, Yang P, Lopez-Berestein G, Lutgendorf SK, Cole SW, Sood AK.

Oncogene. 2015 Aug 10. doi: 10.1038/onc.2015.302. [Epub ahead of print]

The antihypertension drug doxazosin suppresses JAK/STATs phosphorylation and enhances the effects of IFN-α/γ-induced apoptosis.

Park MS, Kim BR, Kang S, Kim DY, Rho SB.

Genes Cancer. 2014 Nov;5(11-12):470-9.

hTERT mediates norepinephrine-induced Slug expression and ovarian cancer aggressiveness.

Choi MJ, Cho KH, Lee S, Bae YJ, Jeong KJ, Rha SY, Choi EJ, Park JH, Kim JM, Lee JS, Mills GB, Lee HY.

Oncogene. 2015 Jun;34(26):3402-12. doi: 10.1038/onc.2014.270. Epub 2014 Aug 25.

The antihypertension drug doxazosin inhibits tumor growth and angiogenesis by decreasing VEGFR-2/Akt/mTOR signaling and VEGF and HIF-1α expression.

Park MS, Kim BR, Dong SM, Lee SH, Kim DY, Rho SB.

Oncotarget. 2014 Jul 15;5(13):4935-44.

Meeting Abstracts on the Subject

From 2007 AACR Meeting

Neuroendocrine Modulation of Signal Transducer and Activator of Transcription-3 in Ovarian Cancer

  1. Requests for reprints:
    Anil K. Sood, Departments of Gynecologic Oncology and Cancer Biology, The University of Texas M. D. Anderson Cancer Center, 1155 Herman Pressler, CPB6.3244, Unit 1362, Houston, TX 77230-1439. Phone: 713-745-5266; Fax: 713-792-7586; E-mail: asood@mdanderson.org.

Abstract

There is growing evidence that chronic stress and other behavioral conditions are associated with cancer pathogenesis and progression, but the mechanisms involved in this association are poorly understood. We examined the effects of two mediators of stress, norepinephrine and epinephrine, on the activation of signal transducer and activator of transcription-3 (STAT3), a transcription factor that contributes to many promalignant pathways. Exposure of ovarian cancer cell lines to increasing concentrations of norepinephrine or epinephrine showed that both independently increased levels of phosphorylated STAT3 in a dose-dependent fashion. Immunolocalization and ELISA of nuclear extracts confirmed increased nuclear STAT3 in response to norepinephrine. Activation of STAT3 was inhibited by blockade of the β1- and β2-adrenergic receptors with propranolol, and by blocking protein kinase A with KT5720, but not with the α receptor blockers prazosin (α1) and/or yohimbine (α2). Catecholamine-mediated STAT3 activation was not inhibited by pretreatment with an anti–interleukin 6 (IL-6) antibody or with small interfering RNA (siRNA)–mediated decrease in IL-6 or gp130. Regarding the effects of STAT3 activation, exposure to norepinephrine resulted in an increase in invasion and matrix metalloproteinase (MMP-2 and MMP-9) production. These effects were completely blocked by STAT3-targeting siRNA. In mice, treatment with liposome-incorporated siRNA directed against STAT3 significantly reduced isoproterenol-stimulated tumor growth. These studies show IL-6–independent activation of STAT3 by norepinephrine and epinephrine, proceeding through the β1/β2-adrenergic receptors and protein kinase A, resulting in increased matrix metalloproteinase production, invasion, and in vivo tumor growth, which can be ameliorated by the down-regulation of STAT3. [Cancer Res 2007;67(21):10389–96]

From 2009 AACR Meeting

Abstract #2506: Functional \#946;2 adrenergic receptors (ADRB2) on human ovarian tumors portend worse clinical outcome

Abstract

Objective: Stress hormones such as catecholamines can augment tumor metastasis and angiogenesis; however, the prevalence and clinical significance of adrenergic receptors in human ovarian cancer is unknown and is the focus of the current study. Methods: After IRB approval, paraffin-embedded samples from 137 patients with invasive epithelial ovarian carcinoma were examined for \#946;1- and \#946;2-adrenergic receptor (ADRB1 and ADRB2, respectively) expression. Correlations with clinical outcomes were determined using parametric and non-parametric tests. Survival analyses were performed using the Kaplan-Meier method. Expression of ADRB1 and -2 was examined by quantitative RT-PCR in 15 freshly extracted human ovarian carcinoma cells. Human ovarian carcinoma cells then underwent time-variable adrenergic stimulation, and tumorigenic and angiogenic cytokine levels were examined by ELISA. Results: Sixty-six percent of the tumors had high expression of ADRB1; 80% of specimens highly expressed ADRB2. Univariate analyses demonstrated that high ADRB1 expression was associated with serous histology (p=0.03) and the presence of ascites (p=0.03), while high expression of ADRB2 was associated with advanced stage (p=0.008). Moreover, high ADRB2 expression was associated with the lower overall survival (2.2 vs. 6.5 years; p<0.001). In multivariate analysis, controlling for FIGO stage, grade, cytoreduction, age, and ADRB expression, only FIGO stage, cytoreduction status, age, and ADRB status retained statistical significance in predicting overall survival. In tumor cells freshly isolated from human ovarian cancers, 75% of samples had high expression of ADRB2 while most lacked ADRB1 compared to normal surface epithelium. Stimulation of the freshly isolated ADRB2-positive human ovarian cancer cells with norepinephrine resulted in increased levels of cAMP and increased angiogenic cytokines IL-6 and VEGF. Conclusions: ADRB2 are frequently found on human ovarian tumors and are strongly associated with poor clinical outcome. These findings support a direct mechanism by which stress hormones modulate ovarian cancer growth and metastasis as well as provide a basis for therapeutic targeting.

And from the 2015 AACR Meeting:

Abstract 3368: Sustained adrenergic signaling activates pro-inflammatory prostaglandin network in ovarian carcinoma

  1. Archana S. Nagaraja1,

Proceedings: AACR 106th Annual Meeting 2015; April 18-22, 2015; Philadelphia, PA

Abstract

Purpose: Catecholamine mediated stress effects are known to induce production of various pro-inflammatory cytokines. However, the mechanism and functional effect of adrenergic signaling in driving inflammation via pro-inflammatory metabolites is currently unknown. Here we address the functional and biological consequences of adrenergic-induced Cox2/PGE2 axis activation in ovarian cancer metastasis.

Methods: We first analyzed global metabolic changes in tumors isolated from patients with known Center for Epidemiologic Studies Depression Scale (CES-D; depressive) scores and tumoral norepinephrine (NE) levels. Beta-adrenergic receptor (ADRB) positive cells (Skov3 and HeyA8) were used to study gene and protein levels of PTGS2 (cyclooxygenase2), PTGES (prostaglandin E synthase) and metabolite PGE2 in vitro and in vivo. To study tumor-specific effects on catecholamine-derived expression of PTGS2, we used a novel DOPC delivery system of PTGS2 siRNA.

Results: Our results revealed that levels of PGs were significantly increased in patients with high depressive scores (>16). PGE2 was upregulated by 2.38 fold when compared to the low CES-D scores. A similar trend was also observed with other pro-inflammatory eicosanoids, such as 6-keto prostaglandin F1 Alpha (2.03), prostaglandin A2 (1.39) and prostaglandin E1 (1.39). Exposure to NE resulted in increased PTGS2 and PTGES (prostaglandin E2 synthase) gene expression and protein levels in Skov3 and HeyA8. PGE2 ELISA confirmed that upon treatment with NE, PGE2 levels were increased in conditioned medium from Skov3 and HeyA8 cells. Treatment with a broad ADRB agonist (isoproterenol) or ADRB2 specific agonist (terbutaline) led to increases in expression of PTGS2 and PTGES as well as PGE2 levels in supernatant. Conversely, treatment with a broad antagonist (propranolol) or an ADRB2 specific antagonist (butoxamine) in the presence of NE abrogated gene expression changes of PTGS2 and PTGES. ChIP analysis showed enrichment of Nf-kB binding to the promoter region of PTGS2 and PTGES by 2.4 and 4.0 fold respectively when Skov3ip1 cells were treated with NE. Silencing PTGS2 resulted in significantly decreased migration (40%) and invasion (25%) of Skov3 cells in the presence of NE. Importantly, in the Skov3-ip1 restraint stress orthotopic model, silencing PTGS2 abrogated stress mediated effects and decreased tumor burden by 70% compared to control siRNA with restraint stress.

Conclusion Increased adrenergic stimulation results in a pro-inflammatory milieu mediated by prostaglandins that drives tumor progression and metastasis in ovarian cancer.

Citation Format: Archana S. Nagaraja, Piotr Dorniak, Nouara Sadaoui, Guillermo Armaiz-Pena, Behrouz Zand, Sherry Y. Wu, Julie K. Allen, Rajesha Rupaimoole, Cristian Rodriguez-Aguayo, Sunila Pradeep, Lin Tan, Rebecca A. Previs, Jean M. Hansen, Peiying Yang, Garbiel Lopez-Berestein, Susan K. Lutgendorf, Steve Cole, Anil K. Sood. Sustained adrenergic signaling activates pro-inflammatory prostaglandin network in ovarian carcinoma. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3368. doi:10.1158/1538-7445.AM2015-3368

Other Article in This Open Access Journal on Ovarian Cancer Include

Beta-Blockers help in better survival in ovarian cancer

Ovarian Cancer Survival Increased 5 Months Overall With Beta Blockers – Study – The Speaker

Model mimicking clinical profile of patients with ovarian cancer @ Yale School of Medicine

Preclinical study identifies ‘master’ proto-oncogene that regulates stress-induced ovarian cancer metastasis | MD Anderson Cancer Center

Beta-Blockers help in better survival in ovarian cancer

Role of Primary Cilia in Ovarian Cancer

Dasatinib in Combination With Other Drugs for Advanced, Recurrent Ovarian Cancer

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New Guidelines and Meeting Information on Advanced Thyroid Cancer as Reported by Cancer Network (Meeting Highlights)

 

Reporter: Stephen J. Williams, Ph.D.

Cancer Network presents exclusive coverage on thyroid cancer from the 15th International Thyroid Congress (ITC) and 85th Annual Meeting of the American Thyroid Association (ATA), held October 18-23 in Lake Buena Vista, Florida.

Vista, Florida.
Conference Reports
ATA Updates Guidelines for Differentiated Thyroid Cancers
Release of newly revised, evidence-based clinical management guidelines for thyroid nodules and differentiated thyroid cancers were announced at the 85th Annual Meeting of the ATA.
FAM83F Protein Implicated in Papillary Thyroid Cancer and Drug Resistance
The FAM83F protein contributes to papillary thyroid cancer cell viability and doxorubicin resistance, according to a study presented at the 85th Annual Meeting of the ATA.
Autophagy Implicated in Vemurafenib Resistance in BRAF-Mutant Thyroid Cancer
Preclinical findings suggest that autophagy inhibition might prove useful in overcoming BRAF-mutant thyroid cancers resistant to vemurafenib.

 

Summary of Newly Released Guidelines on Management of Thyroid Nodules and Differentiated Thyroid Cancers

See Cancer.gov for more information on thyroid cancer

Release of newly revised, evidence-based clinical management guidelines for thyroid nodules and differentiated thyroid cancers were announced at the 15th International Thyroid Congress (ITC) and 85th Annual Meeting of the American Thyroid Association (ATA) in Lake Buena Vista, Florida, and published in Thyroid.

  • The ATA Guidelines Taskforce on Thyroid Nodules and Differentiated Thyroid Cancer authored the guidelines. The Taskforce was chaired by Bryan R. Haugen, MD, of the University of Colorado School of Medicine in Aurora, Colorado.

The updated guidelines reflect

  • advances in the interpretation of biopsy and the use of molecular-marker studies in the clinical differentiation of benign thyroid nodules from thyroid cancer,
  • risk assessment,
  • cancer screening,
  • the management of benign thyroid nodules,
  • the diagnosis and the initial and long-term management of differentiated thyroid cancer.
  • Guidelines modified for long-term management of differentiated thyroid cancer
  • additional research and recommendations needed “for clinical trials and targeted therapy.”

The United States saw an estimated 63,000 newly diagnosed cases of thyroid cancer cases in 2014, up sharply from 37,200 in 2009, when the ATA guidelines were last revised.

– See more at: http://www.cancernetwork.com/ata-2015-thyroid-cancer/ata-updates-guidelines-differentiated-thyroid-cancers?GUID=D63BFB74-A7FD-4892-846F-A7D1FFE0F131&XGUID=&rememberme=1&ts=20102015#sthash.yXbBrS2x.dpuf

 

 

 

Vemurafenib

From 2011 FDA press release on approval of vemurafenib:

FDA NEWS RELEASE

For Immediate Release: Aug. 17, 2011
Media Inquiries: Erica Jefferson, 301-796-4988, erica.jefferson@fda.hhs.gov
Consumer Inquiries: 888-INFO-FDA

FDA approves Zelboraf and companion diagnostic test for late-stage skin cancer
Second melanoma drug approved this year that improves overall survival

The U.S. Food and Drug Administration today approved Zelboraf (vemurafenib), a drug to treat patients with late-stage (metastatic) or unresectable (cannot be removed by surgery) melanoma, the most dangerous type of skin cancer.

Zelboraf is specifically indicated for the treatment of patients with melanoma whose tumors express a gene mutation called BRAF V600E. The drug has not been studied in patients whose melanoma tests negative for that mutation by an FDA approved diagnostic.

Zelboraf is being approved with a first-of-a-kind test called the cobas 4800 BRAF V600 Mutation Test, a companion diagnostic that will help determine if a patient’s melanoma cells have the BRAF V600E mutation.

The BRAF protein is normally involved in regulating cell growth, but is mutated in about half of the patients with late-stage melanomas. Zelboraf is a BRAF inhibitor that is able to block the function of the V600E-mutated BRAF protein.

“This has been an important year for patients with late-stage melanoma. Zelboraf is the second new cancer drug approved that demonstrates an improvement in overall survival,” said Richard Pazdur, M.D., director of the Office of Oncology Drug Products in the FDA’s Center for Drug Evaluation and Research. “In March, we approved Yervoy (ipilimumab), another new treatment for late-stage melanoma that also showed patients live longer after receiving the drug.”

Zelboraf was reviewed under the FDA’s priority review program that provides for an expedited six-month review of drugs that may offer major advances in treatment or that provide a treatment when no adequate therapy exists. Zelboraf and the companion BRAF V600E test are being approved ahead of the drug’s Oct. 28, 2011 goal date and the companion diagnostics’ Nov. 12, 2011 goal date.

Zelboraf’s safety and effectiveness were established in a single international trial of 675 patients with late-stage melanoma with the BRAF V600E mutation who had not received prior therapy. Patients were assigned to receive either Zelboraf or dacarbazine, another anti-cancer therapy. The trial was designed to measure overall survival (the length of time between start of treatment and death of a patient).

The median survival (the length of time a patient lives after treatment) of patients receiving Zelboraf has not been reached (77 percent still living) while the median survival for those who received dacarbazine was 8 months (64 percent still living).

“Today’s approval of Zelboraf and the cobas test is a great example of how companion diagnostics can be developed and used to ensure patients are exposed to highly effective, more personalized therapies in a safe manner,” said Alberto Gutierrez, Ph.D., director of the Office of In Vitro Diagnostic Device Evaluation and Safety in the FDA’s Center for Devices and Radiological Health.

The FDA’s approval of the cobas 4800 BRAF V600 Mutation Test was based on data from the clinical study that also evaluated the safety and effectiveness of Zelboraf. Samples of a patient’s melanoma tissue were collected to test for the mutation.

The most common side effects reported in patients receiving Zelboraf included joint pain, rash, hair loss, fatigue, nausea, and skin sensitivity when exposed to the sun. About 26 percent of patients developed a skin-related cancer called cutaneous squamous cell carcinoma, which was managed with surgery. Patients treated with Zelboraf should avoid sun exposure.

Zelboraf is being approved with a Medication Guide to inform health care professionals and patients of Zelboraf’s potential risks.

In July 2011, the FDA issued a new draft guidance to facilitate the development and review of companion diagnostics. The guidance, currently available for public comment, is intended to provide companies with guidance on the agency’s policy for reviewing a companion diagnostic and the corresponding drug therapy.

Melanoma is the leading cause of death from skin disease. The National Cancer Institute estimated that 68,130 new cases of melanoma were diagnosed in the United States during 2010; about 8,700 people died from the disease.

Zelboraf is marketed by South San Francisco based-Genentech, a member of the Roche Group. The cobas 4800 BRAF V600 Mutation Test is manufactured by Roche Molecular Systems in Pleasanton, Calif.

 

More Articles in this Open Access Journal on Thyroid Cancer Include

 

The Experience of a Patient with Thyroid Cancer

Thyroid Cancer: The Evolution of Treatment Options

The Relation between Coagulation and Cancer affects Supportive Treatments

 

Read Full Post »


Early Diagnosis

Reporter: Stephen J. Williams, Ph.D.

This post contains a curation of all Early Diagnosis posts on this site as well as a curation of the Early Detection Research Network.

Early Research Detection Network (EDRN)

Welcome to EDRN

The Early Detection Research Network (EDRN), an initiative of the National Cancer Institute (NCI), brings together dozens of institutions to help accelerate the translation of biomarker information into clinical applications and to evaluate new ways of testing cancer in its earliest stages and for cancer risk.

Getting Started…

Check out the EDRN Highlights — a listing of our accomplishments and milestones.

 

► Scientific Components ► For Public, Patients, Advocates
► Collaborative Opportunities (how to join EDRN) ► For Researchers

Highlights

Highlights of the accomplishments of the Early Detection Research Network.

A brief list of major EDRN-developed assays that have been adapted for clinical use is described in the table below:

Detection/Biomarker Assay Discovery Refine/Adapt for Clin Use Clinical Validation Clinical Translation
Blood proPSA FDA approved
Urine PCA3 FDA approved
OVA1™ for Ovarian Cancer FDA approved
ROMA Algorithm for CA125 and HE4 Tests for Pelvic Mass Malignancies FDA approved
Blood/DCP and AFP-L3 for Hepatocellular Carcinoma FDA approved
Blood GP73 Together with AFP-L3 used  for monitoring cirrhotic patients for HCC in China
MiPS (Mi Prostate Score Urine test), Multiplex analysis of T2-ERG gene fusion, PCA3 and serum PSA In CLIA Lab
FISH to detect T2S:Erg fusion for Prostate Cancer In CLIA Lab
GSTP1 methylation for repeat biopsies in prostate cancer In CLIA Lab
Mitochondrial deletion for detection of prostate cancer In CLIA Lab
Somalogic 12-marker panel for Lung Cancer In CLIA Lab
80-gene panel for Lung Cancer In CLIA Lab
Vimentin Methylation Marker for Colon Cancer In CLIA Lab
Galectin-3 ligand for detection of adenomas and colon cancer In CLIA Lab
8-gene panel for Barrett’s Esophagus In CLIA Lab
SOPs for Blood (Serum, Plasma), Urine, Stool Frequently used by biomarker research community
EDRN Pre/Validation Specimen Reference Sets (specimens from well characterized and matched cases and controls from specific disease spectra) Frequently used by biomarker research community

Since its inception in 1999 EDRN has achieved several key milestones, summarized below:

1998 through 2000: Inception and Inauguration of EDRN

2001 to 2003: Meeting the Challenges to Harness and Share Emerging Scientific Knowledge

  • EDRN Second Report, Translational Research to Identify Early Cancer and Cancer Risk, October 2002, http://edrn.nci.nih.gov/docs.) published.
  • EDRN joined the Gordon Research Conferences to co-host the New Frontiers in Cancer detection and Diagnosis in 2002.

 

  • Guidelines Set for Studies Measuring Biomarker Predictive Power Journal of National Cancer Institute (Vol. 93, No. 14, July 18, 2001).
  • EDRN Associate Membership Program Initiated: This novel approach to make EDRN inclusive has been extremely successful. EDRN has now more than 120 Associate Members who are significantly contributing to EDRN efforts in biomarker discovery, development and validation.

2003 to 2004: Network Surges Ahead in Real-time

  • Collaborative Discovery and Validation Projects:  More than 100 collaborative projects spanned the various organ sites. These projects are monitored through the EDRN’s electronic System Information System (eSIS).
  • EDRN Virtual Specimen Bank and Validation Management System Launched: The EDRN Virtual Specimen Bank, also known as ERNE knowledge system, was deployed to 10 institutions in early 2003, allowing a common web-based query to search for available specimens across the EDRN Clinical Epidemiology and Validation Centers https://ginger.fhcrc.org/edrn/imp/GateServlet?pwd. VSIMS was created to allow multiple studies to be administered efficiently by minimizing development time with standardization of information and data management across multiple activities and research sites. This system encompasses all the security features of Food and Drug Administration (FDA)-required auditing systems.
  • Partnership on the Plasma Proteome Project (PPP) Initiative of the Human Proteome Organization (HUPO): PPP project was initiated to evaluate multiple technology platforms, develop bioinformatic tools and standards for protein identification, and create a database of the plasma proteome. The entire study was published in the August issue of the journal Proteomics August 2005, Volume 4 (4), pp 1045-1450.

2005 to 2008: An Investment in Prevention

  • In late 2006, EDRN’s Program for Rapid, Independent Diagnostic Evaluation (PRIDE), was established (http://grants.nih.gov/grants/guide/notice-files/NOT-CA-07-003.html ) as an administrative means to assist extramural investigators in successfully conducting cross-laboratory validation of biomarkers. Ten applications have been reviewed and five are being supported.
  • EDRN underwent external reviews in 2007 and 2008.
  • The Canary Foundation, Palo Alto, CA signed a Memorandum of Understanding with EDRN, NCI on supporting prostate cancer surveillance network of investigators from seven institutions. The tissue and serum will be collected during a three-year period and will be made available to extramural scientists for discovery and validation research.
  • The Lustgarten Foundation, N.Y., funded 6 institutions to generate monoclonal antibodies and associated hybridoma cell lines for pancreatic cancer antigens (biomarkers) identified by EDRN and non-EDRN investigators. These resources will be stored at the NCI-Frederick Facility for distribution to extramural investigators.

2009 to 2011: Realizing Investment for Clinical Use

  • Two biomarker tests approved by FDA and two IVDs pending FDA review.
  • Six biomarker tests offered by CLIA labs.
  • One biomarker test approved for clinical use outside the USA

A Curation of Posts on Early Detection of Cancer and Other Early Detection Networks is Included Below

 

BRCA 1 and 2 and Early Detection of Cancer

Early Detection of Prostate Cancer: American Urological Association (AUA) Guideline

Mechanism involved in Breast Cancer Cell Growth: Function in Early Detection & Treatment

Warning signs may lead to better early detection of ovarian cancer

Cancer Detection

Biomarker tool development for Early Diagnosis of Pancreatic Cancer: Van Andel Institute and Emory University

China, India, and Russia account for 46% of all new cancer cases globally, as well as 52% of cancer-related mortality per 4/2014 Lancet Oncology article

 

Read Full Post »


New Topoisomerase Inhibitors in Clinical Trials

Curator: Stephen J. Williams, Ph.D.

Below is a great review of topoisomerase in cancer, approved inhibitors as well as some in clinical trials.

Biomolecules 2015, 5, 1652-1670; doi:10.3390/biom5031652

OPEN ACCESS

biomolecules

ISSN 2218-273X

www.mdpi.com/journal/biomolecules/

Review

Inhibition of Topoisomerase (DNA) I (TOP1): DNA Damage Repair and Anticancer Therapy

Yang Xu and Chengtao Her *

School of Molecular Biosciences, College of Veterinary Medicine, Washington State University, Mail Drop 64-7520, Pullman, WA 99164, USA; E-Mail: davidxy22@vetmed.wsu.edu

* Author to whom correspondence should be addressed; E-Mail: cher@wsu.edu; Tel.: +1-509-335-7537; Fax: +1-509-335-4159.

Academic Editors: Wolf-Dietrich Heyer, Thomas Helleday and Fumio Hanaoka Received: 22 May 2015 / Accepted: 14 July 2015 / Published: 22 July 2015

Abstract: Most chemotherapy regimens contain at least one DNA-damaging agent that preferentially affects the growth of cancer cells. This strategy takes advantage of the differences in cell proliferation between normal and cancer cells. Chemotherapeutic drugs are usually designed to target rapid-dividing cells because sustained proliferation is a common feature of cancer [1,2]. Rapid DNA replication is essential for highly proliferative cells, thus blocking of DNA replication will create numerous mutations and/or chromosome rearrangements—ultimately triggering cell death [3]. Along these lines, DNA topoisomerase inhibitors are of great interest because they help to maintain strand breaks generated by topoisomerases during replication. In this article, we discuss the characteristics of topoisomerase (DNA) I (TOP1) and its inhibitors, as well as the underlying DNA repair pathways and the use of TOP1 inhibitors in cancer therapy.

Biomolecules 2015, 5                                                                                                                           1653

  1. Type IB Topoisomerases and Inhibitors
    1.1. TOP1

DNA topoisomerases resolve topological constraints that may arise from DNA strand separation and are therefore important for transcription and replication [4]. There are six topoisomerases in humans, classified as Type IA, IB and IIA. Type IA topoisomerases TOP3a and TOP3b cleave one DNA strand to relax only negative supercoiling. In addition, TOP3a forms the BTR complex with BLM and RMI1/2, which plays a role in the dissolution of double-Holliday junctions [5]. Type IIA topoisomerases TOP2a and TOP2b generate double-strand breaks on one DNA molecule to allow the passing of other DNA strands [6]. Topoisomerases are attractive drug targets in cancer therapy. For example, the commonly used anticancer agents doxorubicin and etoposide (VP-16) are TOP2 inhibitors [7]. Type IB topoisomerases include the nuclear TOP1 and mitochondrial TOP1mt [4]. TOP1 initiates the DNA relaxation by nicking one DNA strand. It then forms a TOP1-DNA cleavage complex (TOP1cc) by covalently linked to the 3′-phosphate end via its tyrosine residue Y723 (3′-P-Y). Following the resolution of topological entanglements and the removal of TOP1, the 5′-hydroxyl end is realigned with the 3′-end for religation. Each nicking-closing cycle enables the relaxation of one DNA supercoiling (Figure 1).

Figure 1. A schematic representation of strand passages catalyzed by three types of topoisomerases (adapted from ref. [8]).

fig1topto

TOP1 is essential for embryonic development in mammals [9]. Although TOP1 plays an important role in the deconvolution of supercoils arising amid DNA replication, the precise steps involved with

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the recruitment of TOP1 to topological constraints remains to be revealed. It appears that in yeast TOP1 travels at a distance of 600 bp ahead of the replication fork [10] and remains associated with the GINS-MCM complex [11]. However, the yeast TOP1 is distinct from its human counterpart in that it has little effect on fork progression or the firing of replication origin [12]. In humans, TOP1 binds to the regions of the pre-replicative complex in cells during the M, early G1, and G1/S phases of the cell cycle to control the firing of replication origins [12]. This difference may explain why yeast cells are viable in the absence of TOP1. In addition, TOP1 also has functions in transcription that are independent of its role in resolving DNA topological entanglements. First, TOP1 is known to repress transcription by binding to TFIID [13]. Second, inhibition of TOP1 can cause the induction of c-Jun in leukemia cells, suggesting its additional role in the control of transcription [14]. Furthermore, TOP1 interacts with the splicing factor ASF/SF2 by which it promotes the maturation of RNA—through suppressing the formation of R-loops (RNA-DNA hybrids)—and prevents collision between transcription bubble and replication fork [15,16]. It appears that the levels of TOP1 have to be dynamically regulated. In B cells, TOP1 is reduced by activation-induced cytidine deaminase (AID) to facilitate class-switch recombination (CSR) and somatic hypermutation (SHM) [17,18]. Although TOP1mt is important for mitochondrial integrity and metabolism, mice lacking mitochondrial TOP1mt are viable and fertile but they are associated with increased negative supercoiling of mtDNA [19,20].

1.2. TOP1 Inhibitors

Stabilization of TOP1cc by topoisomerase poison is detrimental to cells due to the disruption of DNA uncoiling, increased strand breaks, and unstable RNA transcripts as well as incomplete DNA replication [21]. The TOP1 inhibitor camptothecin (CPT), first isolated from the Chinese tree Camptotheca acuminate, was clinically used for cancer treatment long before it was identified as a TOP1 inhibitor [22]. Due to side effects, CPT is no longer used clinically and it has been replaced by more effective and safer TOP1 inhibitors [23]. Currently, CPT derivatives topotecan (trade name: Hycamtin) and irinotecan (CPT-11, trade name: Camptosar) are routinely used to treat colorectal, ovarian and lung cancers, while a few other TOP1 inhibitors are being tested in clinical trials.

CPT is a 5-ring alkaloid that is active in its closed E-ring (lactone) form but it is inactive with an open E-ring (carboxylate) at physiological and alkaline pH [24]. Therefore, CPT is not effective for inhibiting TOP1mt due to a higher pH mitochondrial environment. The inactive form of CPT tends to bind to serum albumin, which might be a reason for its side effects. CPT is highly specific for TOP1 and the binding is of relatively low affinity and can be reversed after drug removal. These features make the action of CPT controllable [24], and in fact CPT is widely used in studies of replication-associated DNA damage response. There are a few CPT derivatives and non-CPT TOP1 inhibitors [4,8,24]. For example, CPT derivatives Diflomotecan and S39625 were designed to stabilize the E-ring. Irinotecan has the bis-piperidine side chain to increase its water solubility, but it also contributes to some side effects. Non-CPTs—such as indolocarbazoles, phenanthrolines (e.g., ARC-111) and indenoisoquinolines—refer to drugs that have no typical CPT E-ring structures but they can still specifically target TOP1 and bind irreversibly to TOP1cc. Some of the CPT derivatives (i.e., Gimatecan and Belotecan) and non-CPTs (i.e., NSC 725776 and NSC 724998) are presently tested in clinical trials [23].

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How does CPT trap TOP1cc? Analysis of the crystal structure and modeling suggest that CPT-TOP1-DNA forms a ternary complex to prevent the two DNA ends from religation [25–27]. Although it is still controversial on how CPT is intercalated into DNA, it seems that CPT traps TOP1cc with a thymine (T) at the -1 position and a guanine (G) at the +1 position on the scissile strand, and it is therefore sequence-specific [28]. Three amino acid residues of the TOP1 enzyme, R364, D533 and N722, combined with DNA bases, contribute to the stabilization of the ternary complex by forming hydrogen bonds and hydrophobic interactions. It is of note that several point mutations, including N722S, in Camptotheca acuminata TOP1 confer resistance to CPT [29]. Interestingly, the same amino acids also contribute to the inhibition of TOP1 by non-CPT drugs [24].

  1. Repair of TOP1 Poison-Induced DNA Lesions

As aforementioned, CPT-induced trapping of TOP1cc creates a single strand break with a free 5′-hydroxyl group, whereas the 3′-phosphate is connected to Y723 of TOP1 (3′-P-Y). At least two pathways contribute to the repair of DNA lesions created by TOP1 poison [30]. The tyrosyl-DNA-phosphodiesterase (TDP1) pathway starts with the ubiquitination and proteasome-mediated degradation of TOP1 in the CPT-TOP1-DNA complex to generate a 3′-P end linked to a short peptide [31]. TDP1 then cleaves the P-Y bond to release the 3′-P end; however, the 3′-P end cannot be directly ligated to the 5′-OH end because of the requirements of DNA ligases. The human polynucleotide kinase (PNKP) can process the DNA ends by functioning as both a 3′-phosphatase and a kinase to generate the required 3′-OH and 5′-P termini for direct ligation. The rest of the repair events can be best described by the single-strand break (SSB) repair pathway, which will be discussed below. Indeed, TDP1 and PNKP are tightly associated with the SSB repair machinery [32,33].

The endonuclease pathway requires multiple endonucleases to excise the DNA—usually at a few nucleotides away from the 3′-P-TOP1 end – on the scissile strand to release the DNA-TOP1 complex [30]. Initial studies were carried out to identify genes that functioned in CPT repair in the absence of TDP1 in yeast [34,35]. These studies led to the identification of RAD1-RAD10, SLX1-SLX4, MUS81-MMS4, MRE11-SAE2 as well as genes involved in recombination. The RAD1-RAD10 (human XPF/ERCC4-ERCC1) complex is a DNA structure-specific endonuclease that can act on 5′ overhang structures [36]. Interestingly, the cleavage site of XPF-ERCC1 is in the non-protruding DNA strand, about 3–4 nucleotides away from the 3′ end [36]. Therefore, trapped TOP1ccs can be removed by this endonuclease activity. Likewise, MUS81-MMS4 (human MUS81-EME1) can also cleave nicked duplex at the 5′ of the nick [37]. The SLX1-SLX4 endonuclease, although not tested on nicked duplexes, is able to process 3′ flap and other DNA structures [38,39]. In human cells, SLX4 also associates with XPF-ERCC1 and MUS81-EME1 endonucleases to process specific DNA intermediates [39,40]. Moreover, MRE11-RAD50 cleaves the 3′-P-Y bond and resects DNA to produce a 3′-OH end [41]. A direct role of SAE2 (human CtIP) in processing 3′-P-TOP1 is unknown, and its endonuclease activity appears to be limited to the 5′ flap or DNA “hairpin” structures [42,43]. Nonetheless, the endonuclease activity of CtIP is essential for processing CPT adducts [42]. In addition, like CtIP, the 5′ flap endonuclease RAD27 (human FEN1) seems to be unable to directly process 3′-P-TOP1 ends [44]. However, the gap endonuclease activity of FEN1 is important for processing stalled replication forks and CPT-induced adducts [45]. The role of FEN1 in SSB repair will be discussed further in the next section.

Biomolecules 2015, 5                                                                                                                           1656

During DNA replication, SSBs created by CPT are most likely converted to double-strand breaks (DSBs) by replication fork runoff. This conversion appears to be dependent on the proteolysis of TOP1 [46]. The repair of one-ended DSBs, as will be discussed in the next section, is largely dependent on homologous recombination (HR). However, low doses of CPT may also induce PARP1 and/or RAD51 dependent replication fork regression—generating no or few DSBs [47,48]. The regressed fork leads to the formation of a “chicken foot” DNA structure by newly synthesized strands [3,49,50]. The formation of regressed fork can be largely suppressed by ATR, EXO1, and DNA2 [51–53]. However, fork reversal can also be beneficial as it provides time for the repair of TOP1-induced DNA lesions by TDP1, thereby preventing DSB formation and the activation of error-prone non-homologous end-joining (NHEJ) [30].

  1. Pathways Involved in the Repair of CPT-Induced DNA Lesions

Normal cells use DNA damage response (DDR) pathways to maintain genomic stability [54]. As aforementioned, SSB and DSB repair mechanisms are the two major DDR pathways that repair TOP1-induced DNA lesions. Paradoxically, cancer cells exploit DDR pathways to accumulate necessary genomic alterations for promoting proliferation. Furthermore, altered DDR and apoptotic responses in cancer cells are the major obstacles to successful chemotherapy. Thus, the delineation of TOP1-related SSB and DSB repair mechanisms is of great importance for identifying drug targets that can selectively affect cancer cell survival.

3.1. Single-Strand Break (SSB) Repair

Trapping of TOP1cc results in a 3′-P-TOP1 end and a 5′-OH terminus. Because the two ends cannot be directly religated, the persisting SSB is likely to be detected by PARP1 in which activated PARP1 catalyzes the synthesis of poly(ADP-ribose) (PAR) chains for recruiting repair proteins [55]. This reaction can be rapidly reversed by PARG, which hydrolyzes the PAR chains. The PAR chains at the SSB sites are important for the recruitment of XRCC1 that functions as a loading dock for other SSB repair proteins including TDP1 and PNKP. TDP1 generates 3′-P and PNKP converts 3′-P to 3′-OH, and PNKP also converts 5′-OH to 5′-P, making ends compatible for religation with no base loss. The rejoining of the 3′-OH and 5′-P ends is mainly mediated by LIG3, in which XRCC1 mediates the recruitment of LIG3.

If the trapped TOP1cc intermediates are processed by endonucleases, the initial SSBs will be converted to 3′-OH and 5′-OH ends with a gap over a few nucleotides (in the case of XPF-ERCC1, the loss is in the range of 3–4 nt), leading to the activation of PARP1 and XRCC1 recruitment. Consequentially, Pol3 recruited by XRCC1 can catalyze the gap filling, and PCNA-Polö/E also plays a role in this process [55]. If the 5′-OH is not processed by PNKP, the 5′-flap resulted from gap filling is likely to be removed by FEN1, which explains why FEN1 deficiency also leads to an increased CPT sensitivity. The final ligation is catalyzed by LIG1 because of the presence of PCNA.

Biomolecules 2015, 5                                                                                                                           1657

3.2. Double-Strand Break (DSB) Repair

Successful DSB repair requires concerted actions of proteins involved in DNA damage signaling and repair [54]. To repair TOP1 poison-induced DNA lesions, ATR signaling is required due to the runoff of replication fork and the presence of long single-strand DNA (ssDNA) [56]. The full activation of ATR follows a “two-man” rule—the ssDNA-ATRIP-dependent recruitment of ATR kinase and the RAD17 clamp loader/9-1-1/TOPBP1 mediator loading at the ssDNA-dsDNA junction. ATR phosphorylates CHEK1 to harness cell cycle arrest. If one-ended DSB is formed, ATM will be activated through the action of the MRE11-RAD50-NBS1 (MRN) complex. ATM mainly phosphorylates CHEK2 to mediate cell cycle arrest. Both ATM and ATR are able to phosphorylate hundreds of proteins in response to DSB formation [57]. One remarkable substrate is the histone H2AX, which can be phosphorylated by both kinases to yield g-H2AX. It is conceived that the propagation of g-H2AX signaling along the chromatin facilitates MDC1 recruitment and BRCA1 signaling via the MDC1-RNF8-RNF168-RAP80 ubiquitin cascade—events that are essential for HR [58].

The repair of TOP1 poison-induced DNA lesions is in essence the repair of one-ended DSBs, which facilitates the restoration of replication forks to restart DNA replication. It is important to note that one-ended DSB repair occurs in the S phase and relies on HR rather than NHEJ [59]. The first step in HR is end resection to generate a 3′-overhang for homology searching. A TOP1 cleavage in the leading strand may require end resection by the MRN-CtIP-BRCA1 and BLM-EXO1-DNA2 complexes [60], whereas a cleavage in the lagging strand automatically forms a 3′-overhang. Rad51 then associates with the 3′-ssDNA to form a nucleofilament for strand invasion, which leads to the formation of a D-loop structure [61]. This process continues with DNA synthesis, branch migration and the resolution of Holliday junction structures to reconstitute a functional replication fork [62]. TOP1 poisons can also lead to the formation of two-ended DSB if two replication forks collide into each other at the site of SSB. The repair of this type of DSBs is not aimed for fork restoration and can be accomplished by the classical DSB repair mechanisms [61].

3.3. Genes Involved in CPT-Induced Damage Repair

A long list of genes, in which mutations confer sensitivity to CPT in yeast, chicken or mammalian cells, has been compiled [24,30,63]. With no surprise, many genes involved in SSB and DSB repair are on the list, such as PARP1, XRCC1, PNKP, TDP1 for SSB repair; MRN, ATM-CHK2, ATR-CHK1 for DSB signaling; BRCA1/2, XRCC2, XRCC3 for HR. Most recently, the hMSH5-FANCJ complex has also been implicated to play a role in CPT-induced DNA damage response and repair [64]. Mutations in the binding partners of these repair factors are also likely to sensitize cells to CPT treatment. For example, depletion of the MRN-binding partner hnRNPUL increases the sensitivity to CPT [65]; and deficiencies in ZRANB3 and SPIDR, binding partners of PCNA and RAD51, cause CPT hypersensitivity in cancer cells [66–68]. In addition, the two DNA helicases BLM and WRN have also been implicated in the repair of CPT-induced DNA lesions [69,70]. Early studies revealed that chicken BLM knockout cells and human BLM-deficient fibroblasts showed increased sensitivity to CPT [71,72]. On the contrary, mouse BLM knockout embryonic stem cells showed mild resistance to

Biomolecules 2015, 5                                                                                                                           1658

CPT [73]. This discrepancy is likely attributable to the complexity of CPT-induced DNA lesion repair as well as different treatment conditions and experimental systems.

Interstrand crosslinks (ICLs) resemble CPT-induced lesions in that they block both replication and transcription [74]. They may induce replication fork reversal and fork collapse, which require DNA incision for lesion processing and HR for repair. ICL repair is accomplished by the coordinated actions of 17 Fanconi anemia (FA) genes whose mutations contribute to FA in patients [75]. Depletion of FANCP/SLX4 or FANCQ/XPF causes cellular sensitivity to CPT because they form an endonuclease complex involved in the repair of trapped TOP1cc [38]. Likewise, depletion of FANCS/BRCA1, FANCD1/BRCA2, FANCN/PALB2 or FANCO/RAD51C sensitizes cells to CPT because of their involvement in HR [76]. Accordingly, depletion of the FA core complex except FANCM—involved in fork reversal—is not expected to increase CPT sensitivity because they are unable to recognize the trapped TOP1cc [76]. However, the roles of FANCI, D2, J and FAN1 in the process are elusive due to conflicting reports presumably reflecting different experimental systems [76–78]. For example, in a multicolor competition assay, loss of FANCI or FAN1 rendered cells sensitive to CPT treatment [77]. However, this observation could not be recapitulated in studies performed with FANCI-deficient lymphoblasts and FAN1-depleted HEK293 cells [76,79], indicating that the involvement of these two genes in CTP sensitivity might be cell type specific.

It is interesting to note that the MMS22L-TONSL complex plays a prominent role in mediating CPT sensitivity [80–83]. Depletion of this complex impairs RAD51 foci formation and triggers G2/M arrest, indicating that the MMS22L-TONSL complex participates in HR repair. Furthermore, this complex associates with MCM, FACT, ASF1 and histones. FACT and ASF1 are histone chaperones that function in H2A/H2B and H3/H4 chromatin assembly and disassembly, respectively [84]. They recycle parental histones from old DNA strands unwound by MCM and incorporate them into newly synthesized DNA strands. FACT and ASF1 also function in checkpoint signaling; therefore the involvement of MMS22L-TONSL in CPT response implies the existence of a close association between HR, DNA damage signaling and replication restart.

  1. TOP1 Inhibition in Cancer Treatment

The understanding of the function of TOP1 and the cellular effects of TOP1 inhibition has been a stepping-stone for the development of effective CPT derivatives in cancer therapy. Since TOP1 functions in normal and cancer cells, the use of low doses of TOP1 inhibitors are actively sought to treat cancers that heavily rely on the function of TOP1 for survival (e.g., highly malignant, rapid-dividing tumor cells). In fact, the FDA-approved CPT derivatives topotecan and irinotecan are currently used to treat ovarian and colorectal cancers, respectively [24].

Furthermore, the promising results from a Phase I trial have warranted further evaluation of the CPT derivative Diflomotecan in Phase II trials [85]. Other derivatives like Gimatecan, Lurtotecan and Exatecan are also being tested in clinical trials (Table 1). The non-CPT indolocarbazole BMS-250749 showed great anti-tumor activity against preclinical xenograft models [86], but no further evaluation beyond Phase I trials is presently available (Table 2). Another indolocarbazole compound Edotecarin has shown promising anti-tumor activity in xenograft models and it is now advanced to Phase II studies of patients with advanced solid tumors [87]. By contrast, Phenanthroline ARC-111 (topovale)

Biomolecules 2015, 5                                                                                                                             1659

was potently against human tumor xenografts and displayed anti-cancer activity in colon and Wilms’ tumors [88]; however, no result from Phase I clinical trials is available owing to profound bone marrow toxicity [89]. To date, indenoisoquinolines are the most promising non-CPT inhibitors in clinical trials. LMP400 (NSC 743400, indotecan) and LMP776 (NSC 725776, indimitecan) show significant anti-tumor activities in animal models and both are being evaluated in Phase I clinical trials for relapsed solid tumors and lymphomas [8,90].

Table 1. CPT derivatives in clinical trials [91].

Name                            Structure                     Clinical Trial            Malignancy        Reference

Biomolecules 2015, 5                                                                                                                           1660

Given the observation that CPT-mediated TOP1 inhibition provokes DNA repair activities, a synergistic effect is then anticipated on cancer cells by inhibition of TOP1 and downregulation of DNA repair activities. The rationale for this approach is to accelerate the accumulation of DNA breaks and trigger cellular apoptosis, probably through mitotic catastrophe [92]. Which DNA repair pathways can we exploit? Currently, the major interests are in SSB and DSB repair mechanisms. Indeed, PARP inhibitors can enhance the cytotoxicity of TOP1 inhibitors in cancer cell lines as well as in mouse models [93–96]. Phase I studies of combination therapy using PARP inhibitors veliparib or olaparib (FDA-approved) together with topotecan were carried out in patients with advanced solid tumors but showed some dose-dependent side effects [97,98]. TDP1 can be another potential target because it functions directly downstream of PARP1 in the repair of TOP1 poison-induced DNA lesions [99]. TDP1 inhibitors sensitize cells to CPT treatment in vitro [100,101], however in vivo evaluation is presently unavailable due to unsuitable properties of the compounds [102].

Table 2. Non-CPT derivatives in preclinical and clinical trials [91].

Name                       Structure               Clinical Trial            Malignancy             Reference

Indolocarbazoles
(Edotecarin,
BMS-250749)
Phase II

(Edotecarin, Pfizer)

Stomach, breast
neoplasms
Preclinical
(BMS-250749)
Anti-tumor activity
in preclinical
xenograft models
[86,87,103]
Phenanthridines
(ARC-111/topovale)
Anti-tumor activity

Preclinical                    in preclinical            [88,89,103]
xenograft models

Indenoisoquinolines
(LMP400, LMP776)
Phase I                              Lymphomas             [8,90,103]

DSB repair can be targeted by either inhibition of DSB signaling or inhibition of HR. ATM and ATR inhibitors can largely increase the sensitivity to CPT in cancer cells [104,105]. This can be explained by the fact that abrogation of the cell cycle arrest will allow cells with unreplicated or unrepaired chromosomes to enter mitosis thereby triggering mitotic catastrophe and cell death. Similarly, CHEK1 and CHEK2 inhibitors are tested in Phase I studies in combination with irinotecan [106,107]. Inhibitors that can directly block HR proteins are very limited [108]. This is partially attributed to the fact that HR genes are often mutated in cancer cells, thus diminishing the enthusiasm for developing HR inhibitors. One diterpenoid compound, however, was found to be able to inhibit the function of BRCA1 and render cytotoxicity in human prostate cancer cells [109]. Several RAD51 inhibitors have also been

Biomolecules 2015, 5                                                                                                                           1661

identified but have not been tested in cell lines [110]. Inhibition of BRCA1 and RAD51 can be also achieved indirectly by harnessing corresponding kinases [106]. Clearly, defective hMRE11 sensitizes colon cancer cells to CPT treatment [111]. Although MRE11-deficeint tumor xenografts failed to display significant growth inhibition by irinotecan alone, combining thymidine with irinotecan caused a dramatic growth delay [112].

TOP1 inhibitors might be also useful for treating cancers with BRCA1/2 mutations. The successful use of PARP inhibitors in treating BRCA1/2-deficient tumors has ignited a broad interest in searching for synthetic lethality among DNA damage response and repair genes [113,114]. In the PARP-BRCA1/2 example, the accumulation of SSBs by PARP inhibition would lead to the formation of DSBs during replication. In HR-deficient cells, DSBs can only be repaired by illegitimate (toxic) NHEJ—joining one-ended DSBs from different locations—leading to cell death [115,116]. However, resistance to PARP inhibitors can arise in BRCA1-deficient tumors during treatment from either genetic reversion of BRCA1 mutations or the loss of NHEJ [117–122]. Therefore, it would be beneficial to explore the possibility of developing a similar synthetic lethal strategy to use TOP1 inhibitors in the treatment of BRCA1/2-deficient tumors.

Figure 2. An overview of the effects of TOP1 inhibition is provided. Inhibitors and key DNA repair factors are highlighted.

Biomolecules 2015, 5                                                                                                                         1662

  1. Conclusions

Trapping of TOP1 by inhibitors generates SSBs and DSBs that are repaired by their corresponding repair pathways (Figure 2). Therefore, developing effective TOP1 inhibitors not only provides powerful tools to study DNA replication and repair but also establishes a foundation to devise new synthetic lethal strategies for efficient cancer treatments. The accumulation of DNA strand breaks (SSBs and DSBs) by TOP1 inhibition in HR-deficient tumor cells is expected to enhance cytotoxicity. However, increased DNA repair activities in cancer cells can make TOP1 inhibitors less effective, so silencing of repair pathways in conjunction with the use of TOP1 inhibitors offers an attractive new means for cancer control. Since each tumor is unique, it would be advantageous to identify the individualities of DNA repair pathways or biomarkers reflecting the changes of DNA repair activities in tumor cells [92,123]. This will make it possible to achieve better and predictable prognosis through tailored therapeutic regimens. Given that TOP1 is essential for transcription and DNA replication, future design of novel TOP1 inhibitors and combinational therapy strategies should aim to increase therapeutic efficacy of the inhibitors, thus reducing side effects.

Acknowledgments

The work in the Her laboratory is supported by the NIH grant GM084353.

Author Contributions

Yang Xu and Chengtao Her wrote and revised the article.

Conflicts of Interest

The authors declare that they have no conflicts of interest with the contents of this article.

Please see the following file for the referencesReferences for top paper

From a 2015 Clinical Cancer Research paper:

Phase 1 clinical pharmacology study of F14512, a new polyamine-vectorized anti-cancer drug, in naturally occurring canine lymphoma

Dominique Tierny1, Francois Serres1, Zacharie Segaoula1, Ingrid Bemelmans1, Emmanuel Bouchaert1,

Aurelie Petain2, Viviane Brel3, Stephane Couffin4, Thierry Marchal5, Laurent Nguyen6, Xavier Thuru7,

Pierre Ferre2, Nicolas Guilbaud8, and Bruno Gomes9,*

Abstract

Purpose: F14512 is a new topoisomerase II inhibitor containing a spermine moiety that facilitates selective uptake by tumor cells and increases topoisomerase II poisoning. F14512 is currently in Phase I/II clinical trial in patients with acute myeloid leukemia. The aim of this study was to investigate F14512 potential in a new clinical indication. Because of the many similarities between human and dog lymphomas, we sought to determine the tolerance, efficacy, PK/PD relationship of F14512 in this indication, and potential biomarkers that could be translated into human trials. Experimental design: Twenty-three dogs with stage III-IV naturally occurring lymphomas were enrolled in the Phase 1 dose-escalation trial which consisted of three cycles of F14512 intravenous injections. Endpoints included safety and therapeutic efficacy. Serial blood samples and tumor biopsies were obtained for PK/PD and biomarker studies. Results: Five dose levels were evaluated in order to determine the recommended dose. F14512 was well tolerated, with the expected dose-dependent hematological toxicity. F14512 induced an early decrease of tumoral lymph node cells, and a high response rate of 91% (21/23) with 10 complete responses, 11 partial responses, 1 stable disease and 1 progressive disease. Phosphorylation of histone H2AX was studied as a potential pharmacodynamic biomarker of F14512. Conclusions: This trial demonstrated that F14512 can be safely administered to dogs with lymphoma resulting in strong therapeutic efficacy. Additional evaluation of F14512 is needed to compare its efficacy with standards of care in dogs, and to translate biomarker and efficacy findings into clinical trials in humans.

AND From ASCO 2015 Annual Meeting

Survival impact of switching to different topoisomerase I or II inhibitors-based regimens (topo-I or topo-II) in extensive-disease small cell lung cancer (ED-SCLC): supplemental analysis from JCOG0509.

Abstract:

Background: The J0509 (phase III study for chemotherapy-naive ED-SCLC) demonstrated amrubicin plus cisplatin (AP) was inferior to irinotecan plus cisplatin (IP). However, median overall survival (OS) of both AP and IP (15 and 17 mo) was more favorable than those of previous trials (9-12 mo), probably because switching to different topo-I or topo-II in the second-line therapy, especially the use of topo-II in IP arm, was frequent. This analysis aimed to investigate whether observed survival benefit of IP arm can be explained by the treatment switching, and how post-protocol chemotherapy affected the result of J0509. Methods: Two analysis sets from J0509 were used: all randomized 283 pts and 250 pts who received post-protocol chemotherapy. One pt without initiation date of second-line therapy was excluded. A rank-preserving structural failure time (RPSFT) model was used to estimate “causal survival benefit” that would have been observed if all pts had been followed with the same type of regimen as randomized throughout the follow-up period. Additionally, to assess the survival impact of second-line use of topo-II, OS after initiating second-line therapy (OS2) was analyzed by multivariate Cox models. Results: %treatment switching in IP arm and AP arm was 65.2% (92/141) and 43.7% (62/142). By RPSFT model, estimated OS excluding the effect of the treatment switching was 2.7-fold longer in IP (topo-I) arm than AP (topo-II) arm. This causal survival benefit was stronger than the original report of J0509 (nearly 1.4-fold extension by Cox model), indicating that re-challenging topo-I in IP arm appeared beneficial. The multivariate Cox analysis for OS2 (n = 250) revealed second-line use of topo-II was detrimental (hazard ratio, 1.5; 95%CI, 1.1-2.1). Among sensitive relapsed pts in IP arm, OS2 was favorable in the following order: irinotecan-based regimen > the other topo-I > topo-II. Conclusions: IP remains the standard therapy. Re-challenging topo-I, especially irinotecan-based topo-I, seemed beneficial for IP-sensitive pts. This result should be confirmed in further investigations with large sample size. Clinical trial information: 000000720.

 

 

 

 

Below is actively recruiting clinical trials evaluating topoisomerase inhibitors. Shown are only a few trials for a complete list from CancerTrials.gov please see this link:

https://clinicaltrials.gov/ct2/results?term=topoisomerase+inhibitor&recr=Open#wrapper

A service of the U.S. National Institutes of Health

897 studies found for:    topoisomerase inhibitor | Open Studies

Include only open studies Exclude studies with Unknown status

Status Study
Recruiting A Study of Standard Treatment +/- Enoxaparin in Small Cell Lung Cancer

Condition: Small Cell Lung Cancer
Interventions: Drug: cisplatinum or carboplatin and e.g.etoposide.;   Drug: cisplatinum or carboplatin and e.g.etoposide+enoxaparin
Recruiting A Phase I Study of Indenoisoquinolines LMP400 and LMP776 in Adults With Relapsed Solid Tumors and Lymphomas

Conditions: Neoplasms;   Lymphoma
Interventions: Drug: LMP 400;   Drug: LMP 776
Recruiting A Dose-Ranging Study Evaluating the Efficacy, Safety, and Tolerability of GSK2140944 in the Treatment of Uncomplicated Urogenital Gonorrhea Caused by Neisseria Gonorrhoeae

Condition: Gonorrhea
Intervention: Drug: GSK2140944
Recruiting Selinexor in Combination With Irinotecan in Adenocarcinoma of Stomach and Distal Esophagus

Conditions: Esophageal Cancer;   Gastric Cancer
Interventions: Drug: Selinexor;   Drug: Irinotecan
Recruiting Multimodal Molecular Targeted Therapy to Treat Relapsed or Refractory High-risk Neuroblastoma

Condition: Neuroblastoma Recurrent
Interventions: Drug: Dasatinib;   Drug: Rapamycin;   Drug: Irinotecan;   Drug: Temozolomide
Unknown  Study of the Farnesyl Transferase Inhibitor, R115777, in Combination With Topotecan (NYU 99-32)

Condition: Cancer
Interventions: Drug: R115777 (farnesyl transferase inhibitor);   Drug: Topotecan
Recruiting Pegylated Irinotecan NKTR 102 in Treating Patients With Relapsed Small Cell Lung Cancer

Condition: Recurrent Small Cell Lung Carcinoma
Interventions: Other: Laboratory Biomarker Analysis;   Drug: Pegylated Irinotecan;   Other: Pharmacological Study
Recruiting Selinexor and Chemotherapy in Treating Patients With Relapsed or Refractory Acute Myeloid Leukemia

Conditions: Adult Acute Myeloid Leukemia With 11q23 (MLL) Abnormalities;   Adult Acute Myeloid Leukemia With Del(5q);   Adult Acute Myeloid Leukemia With Inv(16)(p13;q22);   Adult Acute Myeloid Leukemia With t(15;17)(q22;q12);   Adult Acute Myeloid Leukemia With t(16;16)(p13;q22);   Adult Acute Myeloid Leukemia With t(8;21)(q22;q22);   Recurrent Adult Acute Myeloid Leukemia;   Secondary Acute Myeloid Leukemia
Interventions: Drug: mitoxantrone hydrochloride;   Drug: etoposide;   Drug: cytarabine;   Drug: selinexor;   Other: laboratory biomarker analysis;   Other: pharmacological study
Recruiting WEE1 Inhibitor MK-1775 and Irinotecan Hydrochloride in Treating Younger Patients With Relapsed or Refractory Solid Tumors

Conditions: Childhood Solid Neoplasm;   Recurrent Childhood Medulloblastoma;   Recurrent Childhood Supratentorial Primitive Neuroectodermal Tumor;   Recurrent Neuroblastoma
Interventions: Drug: Irinotecan Hydrochloride;   Other: Laboratory Biomarker Analysis;   Other: Pharmacological Study;   Drug: WEE1 Inhibitor AZD1775
Recruiting PARP Inhibitor BMN-673 and Temozolomide or Irinotecan Hydrochloride in Treating Patients With Locally Advanced or Metastatic Solid Tumors

Conditions: Metastatic Cancer;   Unspecified Adult Solid Tumor
Interventions: Drug: PARP inhibitor BMN-673;   Drug: temozolomide;   Drug: irinotecan hydrochloride;   Other: pharmacological study;   Other: laboratory biomarker analysis
Recruiting A Phase II Multicenter, Randomized, Placebo Controlled, Double Blinded Clinical Study of KD018 as a Modulator of Irinotecan Chemotherapy in Patients With Metastatic Colorectal Cancer

Condition: Colorectal Neoplasms
Interventions: Drug: KD018;   Drug: Irinotecan;   Drug: Placebo
Recruiting The Efficacy of the 7 Days Tailored Therapy as 2nd Rescue Therapy for Eradication of H. Pylori Infection

Condition: Helicobacter Infection
Interventions: Procedure: H. pylori culture and antimicrobial susceptibility testing;   Drug: 14 days empirical bismuth quadruple therapy (Proton pump inhibitor);   Drug: Metronidazole;   Drug: Tetracycline;   Drug: tripotassium dicitrate bismuthate;   Drug: 7 days tailored therapy Proton Pump Inhibitor;   Drug: Moxifloxacin;   Drug: Amoxicillin
Recruiting G1T28 (CDK 4/6 Inhibitor) in Combination With Etoposide and Carboplatin in Extensive Stage Small Cell Lung Cancer (SCLC)

Condition: Small Cell Lung Cancer
Interventions: Drug: G1T28 + carboplatin/ etoposide;   Drug: Placebo + carboplatin/ etoposide
Recruiting Trial of Topotecan With VX-970, an ATR Kinase Inhibitor, in Small Cell Lung Cancer

Conditions: Carcinoma, Non-Small -Cell Lung;   Ovarian Neoplasms;   Small Cell Lung Carcinoma;   Uterine Cervical Neoplasms;   Carcinoma, Neuroendocrine
Interventions: Drug: Topotecan;   Drug: VX-970
Recruiting Prospective Analysis of UGT1A1 Promoter Polymorphism for Irinotecan Dose Escalation in Metastatic Colorectal Cancer Patients Treated With Bevacizumab Combined With FOLFIRI as the First-line Setting

Condition: Metastatic Colorectal Cancer
Interventions: Genetic: UGT1A1 genotyping (6,6);   Genetic: UGTIA1 genotyping (6,7);   Genetic: UGTIA1 genotyping (7,7);   Genetic: UGT1A1 non-genotyping;   Drug: bevacizumab (Avastin);   Drug: irinotecan;   Drug: Leucovorin;   Drug: 5-FU
Recruiting A Study of the Bruton’s Tyrosine Kinase Inhibitor, PCI-32765 (Ibrutinib), in Combination With Rituximab, Cyclophosphamide, Doxorubicin, Vincristine, and Prednisone in Patients With Newly Diagnosed Non-Germinal Center B-Cell Subtype of Diffuse Large B-Cell Lymphoma

Condition: Lymphoma
Interventions: Drug: Ibrutinib;   Drug: Placebo;   Drug: Rituximab;   Drug: Cyclophosphamide;   Drug: Doxorubicin;   Drug: Vincristine;   Drug: Prednisone (or equivalent)
Recruiting Irinotecan Combination Chemotherapy for Refractory or Relapsed Brain Tumor in Children and Adolescents

Condition: Brain Tumor
Intervention: Drug: Irinotecan combination chemotherapy
Recruiting A Study To Evaluate PF-04449913 With Chemotherapy In Patients With Acute Myeloid Leukemia or Myelodysplastic Syndrome

Condition: Acute Myeloid Leukemia
Interventions: Drug: PF-04449913;   Drug: Low dose ARA-C (LDAC);   Drug: Decitabine;   Drug: Daunorubicin;   Drug: Cytarabine
Recruiting Veliparib and Pegylated Liposomal Doxorubicin Hydrochloride in Treating Patients With Recurrent Ovarian Cancer, Fallopian Tube Cancer, or Primary Peritoneal Cancer or Metastatic Breast Cancer

Conditions: Estrogen Receptor Negative;   HER2/Neu Negative;   Male Breast Carcinoma;   Progesterone Receptor Negative;   Recurrent Breast Carcinoma;   Recurrent Fallopian Tube Carcinoma;   Recurrent Ovarian Carcinoma;   Recurrent Primary Peritoneal Carcinoma;   Stage IV Breast Cancer;   Triple-Negative Breast Carcinoma
Interventions: Other: Laboratory Biomarker Analysis;   Drug: Pegylated Liposomal Doxorubicin Hydrochloride;   Other: Pharmacological Study;   Drug: Veliparib
Recruiting A Study To Evaluate Ara-C and Idarubicin in Combination With the Selective Inhibitor Of Nuclear Export (SINE) Selinexor (KPT-330) in Patients With Relapsed Or Refractory AML

Condition: Acute Myeloid Leukemia (Relapsed/Refractory)
Interventions: Drug: Selinexor;   Drug: Idarubcin;   Drug: Cytarabine

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