Archive for the ‘Apoptosis’ Category

Accelerating PROTAC drug discovery: Establishing a relationship between ubiquitination and target protein degradation

Posted in Apoptosis, Bio Instrumentation in Experimental Life Sciences Research, Biological Networks, Biomedical Measurement Science, Cancer - General, Cancer and Current Therapeutics, CANCER BIOLOGY & Innovations in Cancer Therapy, Cell Biology, Signaling & Cell Circuits, Childhood cancer, Enzymatic mechanism underlying the synthesis of adenosine triphosphate (ATP), KRAS Mutation, Li-fraumeni syndrome., Proteosome, TP53 - Germline mutations, Ubiquitin, tagged breast cancer, Cancer - General, E3 Ligase, high throughput, MDM2, PROTAC, TUBEs, Ubiquitin ligase, ubiquitin-proteosome, VHL on October 4, 2022| Leave a Comment »

Accelerating PROTAC drug discovery: Establishing a relationship between ubiquitination and target protein degradation

Curator: Stephen J. Williams, Ph.D.

PROTACs have been explored in multiple disease fields with focus on only few ligases like cereblon (CRBN), Von Hippel-Lindau (VHL), IAP and MDM2. Cancer targets like androgen receptor, estrogen receptor, BTK, BCL2, CDK8 and c-MET [[6], [7], [8], [9], [10], [11]] have been successfully targeted using PROTACs. A variety of BET family (BRD2, BRD3, and BRD4)- PROTACs were designed using multiple ligases; MDM2-based BRD4 PROTAC [12], CRBN based dBET1 [13] and BETd-24-6 [14] for triple-negative breast cancer, enhanced membrane permeable dBET6 [15], and dBET57 PROTAC [16]. PROTACs for Hepatitis c virus (HCV) protease, IRAK4 and Tau [[17], [18], [19]] have been explored for viral, immune and neurodegenerative diseases, respectively. Currently, the PROTAC field expansion to vast undruggable proteome is hindered due to narrow focus on select E3 ligases. Lack of reliable tools to rapidly evaluate PROTACs based on new ligases is hindering the progress. Screening platforms designed must be physiologically relevant and represent true PROTAC cellular function, i.e., PROTAC-mediated target ubiquitination and degradation.

In the current study, we employ TUBEs as affinity capture reagents to monitor PROTAC-induced poly-ubiquitination and degradation as a measure of potency. We established and validated proof-of-concept cell-based assays in a 96-well format using PROTACS for three therapeutic targets BET family proteins, kinases, and KRAS. To our knowledge, the proposed PROTAC assays are first of its kind that can simultaneously 1) detect ubiquitination of endogenous, native protein targets, 2) evaluate the potency of PROTACs, and 3) establish a link between the UPS and protein degradation. Using these TUBE assays, we established rank order potencies between four BET family PROTACs dBET1, dBET6, BETd246 and dBET57 based on peak ubiquitination signals (“Ub_Max”) of the target protein. TUBE assay was successful in demonstrating promiscuous kinase PROTACs efficiency to degrade Aurora Kinase A at sub-nanomolar concentrations within 1 h. A comparative study to identify changes in the ubiquitination and degradation profile of KRAS G12C PROTACs recruiting two E3 ligases (CRBN and VHL). All of the ubiquitination and degradation profiles obtained from TUBE based assays correlate well with traditional low throughput immunoblotting. Significant correlation between DC₅₀ obtained from protein degradation in western blotting and Ub_Max values demonstrates our proposed assays can aid in high-throughput screening and drastically eliminate artifacts to overcome bottlenecks in PROTAC drug discovery.

To successfully set up HTS screening with novel PROTACs without pre-existing knowledge, we recommend the following steps. 1. Identify a model PROTAC that can potentially demonstrate activity based on knowledge in PROTAC design or in vitro binding studies. 2. Perform a time course study with 2–3 doses of the model PROTAC based on affinities of the ligands selected. 3. Monitor ubiquitination and degradation profiles using plate-based assay and identify time point that demonstrates Ub_Max. 4. Perform a dose response at selected time point with a library of PROTACs to establish rank order potency.

INTRODUCTION

Ubiquitination is a major regulatory mechanism to maintain cellular protein homeostasis by marking proteins for proteasomal-mediated degradation [1]. Given ubiquitin’s role in a variety of pathologies, the idea of targeting the Ubiquitin Proteasome System (UPS) is at the forefront of drug discovery [2]. “Event-driven” protein degradation using the cell’s own UPS is a promising technology for addressing the “undruggable” proteome [3]. Targeted protein degradation (TPD) has emerged as a new paradigm and promising therapeutic option to selectively attack previously intractable drug targets using PROteolytic TArgeting Chimeras (PROTACs) [4]. PROTACs are heterobifunctional molecules with a distinct ligand that targets a specific E3 ligase which is tethered to another ligand specific for the target protein using an optimized chemical linker. A functional PROTAC induces a ternary E3-PROTAC-target complex, resulting in poly-ubiquitination and subsequent controlled protein degradation [5]. Ability to function at sub-stoichiometric levels for efficient degradation, a significant advantage over traditional small molecules.

PROTACs have been explored in multiple disease fields with focus on only few ligases like cereblon (CRBN), Von Hippel-Lindau (VHL), IAP and MDM2. Cancer targets like androgen receptor, estrogen receptor, BTK, BCL2, CDK8 and c-MET [[6], [7], [8], [9], [10], [11]] have been successfully targeted using PROTACs. A variety of BET family (BRD2, BRD3, and BRD4)- PROTACs were designed using multiple ligases; MDM2-based BRD4 PROTAC [12], CRBN based dBET1 [13] and BETd-24-6 [14] for triple-negative breast cancer, enhanced membrane permeable dBET6 [15], and dBET57 PROTAC [16]. PROTACs for Hepatitis c virus (HCV) protease, IRAK4 and Tau [[17], [18], [19]] have been explored for viral, immune and neurodegenerative diseases, respectively. Currently, the PROTAC field expansion to vast undruggable proteome is hindered due to narrow focus on select E3 ligases. Lack of reliable tools to rapidly evaluate PROTACs based on new ligases is hindering the progress. Screening platforms designed must be physiologically relevant and represent true PROTAC cellular function, i.e., PROTAC-mediated target ubiquitination and degradation.

Cellular PROTAC screening is traditionally performed using cell lines harboring reporter genes and/or Western blotting. While Western blotting is easy to perform, they are low throughput, semi-quantitative and lack sensitivity. While reporter gene assays address some of the issues, they are challenged by reporter tags having internal lysines leading to artifacts. Currently, no approaches are available that can identify true PROTAC effects such as target ubiquitination and proteasome-mediated degradation simultaneously. High affinity ubiquitin capture reagents like TUBEs [20] (tandem ubiquitin binding entities), are engineered ubiquitin binding domains (UBDs) that allow for detection of ultralow levels of polyubiquitinated proteins under native conditions with affinities as low as 1 nM. The versatility and selectivity of TUBEs makes them superior to antibodies, and they also offer chain-selectivity (-K48, -K63, or linear) [21]. High throughput assays that can report the efficacy of multiple PROTACs simultaneously by monitoring PROTAC mediated ubiquitination can help establish rank order potency and guide chemists in developing meaningful structure activity relationships (SAR) rapidly.

In the current study, we employ TUBEs as affinity capture reagents to monitor PROTAC-induced poly-ubiquitination and degradation as a measure of potency. We established and validated proof-of-concept cell-based assays in a 96-well format using PROTACS for three therapeutic targets BET family proteins, kinases, and KRAS. To our knowledge, the proposed PROTAC assays are first of its kind that can simultaneously 1) detect ubiquitination of endogenous, native protein targets, 2) evaluate the potency of PROTACs, and 3) establish a link between the UPS and protein degradation. Using these TUBE assays, we established rank order potencies between four BET family PROTACs dBET1, dBET6, BETd246 and dBET57 based on peak ubiquitination signals (“Ub_Max”) of the target protein. TUBE assay was successful in demonstrating promiscuous kinase PROTACs efficiency to degrade Aurora Kinase A at sub-nanomolar concentrations within 1 h. A comparative study to identify changes in the ubiquitination and degradation profile of KRAS G12C PROTACs recruiting two E3 ligases (CRBN and VHL). All of the ubiquitination and degradation profiles obtained from TUBE based assays correlate well with traditional low throughput immunoblotting. Significant correlation between DC₅₀ obtained from protein degradation in western blotting and Ub_Max values demonstrates our proposed assays can aid in high-throughput screening and drastically eliminate artifacts to overcome bottlenecks in PROTAC drug discovery.

Fig. 1. Schematic representation of TUBE assay to monitor PROTAC mediated cellular ubiquitination of target proteins.

Fig. 2. TUBE based assay screening of PROTACs: Jurkat cell lysates were treated with BRD3-specific PROTACs A) dBET1, B) dBET6, C) BETd24-6, and D) dBET57. Polyubiquitination profiles and Ubmax of BRD3 for each PROTAC were represented as relative CL intensity. Relative CL intensities were calculated by dividing raw CL signals from a given PROTAC dose over DMSO treated samples. Error bars represent standard deviations, n = 3.

Fig. 3. PROTAC mediated degradation of bromodomain proteins analyzed by anti-BRD3 western blotting. Dose response of PROTACs dBET1, dBET6, Betd-24-6 and dBET57 at 45 min in Jurkat cells demonstrates degradation of BRD3, Acting as loading control.

Fig. 4. PROTAC mediated ubiquitination and degradation of AURKA in K562 cells. (A) Time course study to evaluate intracellular ubiquitination and degradation. (B) Western blot analysis of time course study: degradation kinetics (C) A dose response study to evaluate DC50 of the promiscuous kinase PROTAC in K562 cells. (D) Western blot analysis of dose response study to monitor degradation, GAPDH as loading control. Error bars represent standard deviation, n = 3.

SOURCE

https://www.sciencedirect.com/science/article/abs/pii/S0006291X22011792

2022 Albert Lasker Basic Medical Research Award for Integrins—Mediators of Cell-Matrix and Cell-Cell Adhesion

Posted in Apoptosis, Cell Biology, Signaling & Cell Circuits, Cell Processing System in Cell Therapy Process Development, Chemical Biology and its relations to Metabolic Disease, Interviews with Scientific Leaders on September 28, 2022| Leave a Comment »

2022 Albert Lasker Basic Medical Research Award for Integrins—Mediators of Cell-Matrix and Cell-Cell Adhesion

Reporter: Aviva Lev-Ari, PhD, RN

The three recipients of 2022 Albert Lasker Basic Medical Research Award For discoveries concerning the integrins—key mediators of cell-matrix and cell-cell adhesion in physiology and disease are:

Richard O. Hynes, Massachusetts Institute of Technology
Erkki Ruoslahti, Sanford Burnham Prebys
Timothy A. Springer, Boston Children’s Hospital/Harvard Medical School

2022 Basic Award video

https://www.youtube.com/watch?v=4k60P3Pnh30

Acceptance remarks

Richard Hynes
Erkki Ruoslahti
Timothy Springer

Watch 3 Videos

Figure 1A: Pairs that bond
Two protein chains, α and ß, compose the heterodimeric integrins that span the cell membrane. The portion outside affixes to molecules in the extracellular matrix (ECM) or on other cells. Adherence through integrins triggers cytoskeleton assembly and vice versa. Such events can also influence the behavior of other proteins inside the cell. The image shows the matrix-cell type of integrin; a second type mediates cell-cell interactions.
Illustration: Cassio Lynm / © Amino Creative

Figure 1B: Families that stick together
Integrin α and ß subunit each belong to a family of proteins with a shared evolutionary ancestor. Individual members of the α and ß families combine in different ways to create 24 mammalian heterodimers that physically associate with a variety of molecules. In the ECM, these binding partners include collagen, laminin, and other RGD-containing proteins such as fibronectin and fibrinogen; on cells, these partners include proteins such as ICAM-1, which dwells on the surface of white blood cells and cells that line blood vessels. The first integrin identified, the platelet receptor, promotes blood clotting. LFA-1 helps immune cells fight infections in numerous ways.
Illustration: Cassio Lynm / © Amino Creative

Figure 2: Fleeting attachments, profound effects
By fostering adherence between cells and the ECM or other cells, integrins play a key role in a tremendous number of essential physiological interactions.
Illustration: Cassio Lynm / © Amino Creative

Figures Source:

https://laskerfoundation.org/winners/integrins-mediators-of-cell-matrix-cell-adhesion/

Selected Publications – Discovery of Integrins

Cell-Matrix Interactions

Ruoslahti, E., Vaheri. A., Kuusela, P., and Linder, E. (1973). Fibroblast surface antigen: a new serum protein. Biochim. Biophys. Acta. 322, 352-358.

Hynes, R.O. (1973). Alteration of cell-surface proteins by viral transformation and by proteolysis. Proc. Natl. Acad. Sci. USA. 70, 3170-3174.

Pierschbacher, M.D., and Ruoslahti, E. (1984). Cell attachment activity of fibronectin can be duplicated by small synthetic fragments of the molecule. Nature. 309, 30-33.

Pytela, R., Pierschbacher, M.D., and Ruoslahti, E. (1985). A 125/115-kDa cell surface receptor specific for vitronectin interacts with the arginine-glycine-aspartic acid adhesion sequence derived from fibronectin. Proc. Natl. Acad. Sci. USA. 82, 5766-5770.

Pytela, R., Pierschbacher, M.D., Ginsberg, M.H., Plow, E.F., and Ruoslahti, E. (1986). Platelet membrane glycoprotein IIb/IIIa: member of a family of Arg-Gly-Asp-specific adhesion receptors. Science. 231, 1559-1562.

Tamkun, J.W., DeSimone, D.W., Fonda, D., Patel, R.S., Buck, C., Horwitz, A.F., and Hynes, R.O. (1986). Structure of integrin, a glycoprotein involved in the transmembrane linkage between fibronectin and actin. Cell. 46, 271-282.

Hynes, R.O. (1987). Integrins: a family of cell surface receptors. Cell. 48, 549-554.

Ruoslahti, E. (1996). RGD and other recognition sequences for integrins. Annu. Rev. Cell Dev. Biol. 12, 697-715.

Hynes, R.O. (2002). Integrins: bidirectional allosteric signaling machines. Cell. 110, 673-687.

Cell-Cell Interactions

Kurzinger, K., Reynolds, T., Germain, R.N., Davignon, D., Martz, E., and Springer, T.A. (1981). A novel lymphocyte function-associated antigen (LFA-1): cellular distribution, quantitative expression, and structure. J. Immunol. 127, 596-600.

Sanchez-Madrid, F., Nagy, J., Robbins, E., Simon, P., and Springer, T.A. (1983). A human leukocyte differentiation antigen family with distinct alpha subunits and a common beta subunit: the lymphocyte function-associated antigen (LFA-1), the C3bi complement receptor (OKM1/Mac-1), and the p150,95 molecule. J. Exp. Med. 158, 1785-1789.

Thompson, W.S., Miller, L.J., Schmalstieg, F.C., Anderson, D.C., and Springer, T.A. (1984). Inherited deficiency of the Mac-1, LFA-1, p150,95 glycoprotein family and its molecular basis. J. Exp. Med. 160, 1901-1905.

Kishimoto, T.K., Lee, A., Roberts, T.M., and Springer, T.A. (1987). Cloning of the beta subunit of the leukocyte adhesion proteins: homology to an extra-cellular matrix receptor defines a novel supergene family. Cell. 48, 681-690.

Makgoba. M.W., Sanders, M.E., Luce, G.E.G., Dustin, M.L., Springer, T.A., Clark, E.A., Mannoni, P., and Shaw, S. (1988). ICAM-1 a ligand for LFA-1-dependent adhesion of B, T and myeloid cells. Nature. 331, 86-88.

Staunton, D.E., Dustin, M.L., and Springer, T.A. (1989). Functional cloning of ICAM-2, a cell adhesion ligand for LFA-1 homologous to ICAM-1. Nature. 339, 61-65.

Springer, T.A. (1990). Adhesion receptors of the immune system. Nature. 346, 425-434.

Lawrence, M.B., and Springer, T.A. (1991). Leukocytes roll on a selectin at physiologic flow rates: distinction from and prerequisite for adhesion through integrins. Cell. 65, 859-873.

Luo, B.-H., Carman, C.V., and Springer, T.A. (2007) Structural basis of integrin regulation and signaling. Annu. Rev. Immunol. 25, 619-647.

Li, J., Yan, J., and Springer, T.A. (2021). Low-affinity integrin states have faster ligand-binding kinetics than the high-affinity state. eLife. 10, 1-22. e73359. doi: 10.7554/eLife.73359.

SOURCE

https://laskerfoundation.org/winners/integrins-mediators-of-cell-matrix-cell-adhesion/

Read Full Post »

New studies link cell cycle proteins to immunosurveillance of premalignant cells

Posted in Apoptosis, Biological Networks, Biological Networks, Gene Regulation and Evolution, Cancer - General, CANCER BIOLOGY & Innovations in Cancer Therapy, Cancer-Immune Interactions, Cell Biology, Signaling & Cell Circuits, Circulating Tumor Cells (CTC), Disease Biology, DNA repair, Efficacy of Anti-Tumor T Cells, Exosomes, Exosomes: Natural Carriers for siRNA Delivery, Immune Modulatory, Immuno-Oncology & Genomics, Immunology, KRAS Mutation, Modulating Macrophages in Cancer Immunotherapy, NK Cell-Based Cancer Immunotherapy, TP53 - Germline mutations, tagged CDKI, cell cycle, cell cycle arrest, cell cycle protein, cellular senescence, DNA repair or transcription factor genes, Immunology, immunosuppression, immunosurveillance, NF-kB, p21, p53, premalignant, transcriptional, transcriptional regulation, tumor suppressors on December 16, 2021| Leave a Comment »

New studies link cell cycle proteins to immunosurveillance of premalignant cells

Curator: Stephen J. Williams, Ph.D.

The following is from a Perspectives article in the journal Science by Virinder Reen and Jesus Gil called “Clearing Stressed Cells: Cell cycle arrest produces a p21-dependent secretome that initaites immunosurveillance of premalignant cells”. This is a synopsis of the Sturmlechener et al. research article in the same issue (2).

Complex organisms repair stress-induced damage to limit the replication of faulty cells that could drive cancer. When repair is not possible, tissue homeostasis is maintained by the activation of stress response programs such as apoptosis, which eliminates the cells, or senescence, which arrests them (1). Cellular senescence causes the arrest of damaged cells through the induction of cyclin-dependent kinase inhibitors (CDKIs) such as p16 and p21 (2). Senescent cells also produce a bioactive secretome (the senescence-associated secretory phenotype, SASP) that places cells under immunosurveillance, which is key to avoiding the detrimental inflammatory effects caused by lingering senescent cells on surrounding tissues. On page 577 of this issue, Sturmlechner et al. (3) report that induction of p21 not only contributes to the arrest of senescent cells, but is also an early signal that primes stressed cells for immunosurveillance.Senescence is a complex program that is tightly regulated at the epigenetic and transcriptional levels. For example, exit from the cell cycle is controlled by the induction of p16 and p21, which inhibit phosphorylation of the retinoblastoma protein (RB), a transcriptional regulator and tumor suppressor. Hypophosphorylated RB represses transcription of E2F target genes, which are necessary for cell cycle progression. Conversely, production of the SASP is regulated by a complex program that involves super-enhancer (SE) remodeling and activation of transcriptional regulators such as nuclear factor κB (NF-κB) or CCAAT enhancer binding protein–β (C/EBPβ) (4).

Senescence is a complex program that is tightly regulated at the epigenetic and transcriptional levels. For example, exit from the cell cycle is controlled by the induction of p16 and p21, which inhibit phosphorylation of the retinoblastoma protein (RB), a transcriptional regulator and tumor suppressor. Hypophosphorylated RB represses transcription of E2F target genes, which are necessary for cell cycle progression. Conversely, production of the SASP is regulated by a complex program that involves super-enhancer (SE) remodeling and activation of transcriptional regulators such as nuclear factor κB (NF-κB) or CCAAT enhancer binding protein–β (C/EBPβ) (4).

Sturmlechner et al. found that activation of p21 following stress rapidly halted cell cycle progression and triggered an internal biological timer (of ∼4 days in hepatocytes), allowing time to repair and resolve damage (see the figure). In parallel, C-X-C motif chemokine 14 (CXCL14), a component of the PASP, attracted macrophages to surround and closely surveil these damaged cells. Stressed cells that recovered and normalized p21 expression suspended PASP production and circumvented immunosurveillance. However, if the p21-induced stress was unmanageable, the repair timer expired, and the immune cells transitioned from surveillance to clearance mode. Adjacent macrophages mounted a cytotoxic T lymphocyte response that destroyed damaged cells. Notably, the overexpression of p21 alone was sufficient to orchestrate immune killing of stressed cells, without the need of a senescence phenotype. Overexpression of other CDKIs, such as p16 and p27, did not trigger immunosurveillance, likely because they do not induce CXCL14 expression.In the context of cancer, senescent cell clearance was first observed following reactivation of the tumor suppressor p53 in liver cancer cells. Restoring p53 signaling induced senescence and triggered the elimination of senescent cells by the innate immune system, prompting tumor regression (5). Subsequent work has revealed that the SASP alerts the immune system to target preneoplastic senescent cells. Hepatocytes expressing the oncogenic mutant NRAS^G12V (Gly¹²→Val) become senescent and secrete chemokines and cytokines that trigger CD4⁺ T cell–mediated clearance (6). Despite the relevance for tumor suppression, relatively little is known about how immunosurveillance of oncogene-induced senescent cells is initiated and controlled.

Source of image: Reen, V. and Gil, J. Clearing Stressed Cells. Science Perspectives 2021;Vol 374(6567) p 534-535.

References

2. Sturmlechner I, Zhang C, Sine CC, van Deursen EJ, Jeganathan KB, Hamada N, Grasic J, Friedman D, Stutchman JT, Can I, Hamada M, Lim DY, Lee JH, Ordog T, Laberge RM, Shapiro V, Baker DJ, Li H, van Deursen JM. p21 produces a bioactive secretome that places stressed cells under immunosurveillance. Science. 2021 Oct 29;374(6567):eabb3420. doi: 10.1126/science.abb3420. Epub 2021 Oct 29. PMID: 34709885.

Double Mutant PI3KA Found to Lead to Higher Oncogenic Signaling in Cancer Cells

Posted in Apoptosis, CANCER BIOLOGY & Innovations in Cancer Therapy, Cancer Genomics, Cell Biology, Cell Biology, Signaling & Cell Circuits, Childhood cancer, Computational Biology/Systems and Bioinformatics, Genetics & Pharmaceutical, Genome Biology, Genomic Expression, Pharmaceutical Drug Discovery, tumor microenvironment, tagged alpelsib, breast cancer, metastatic disease, mutation, PI3 kinase, PI3K/AKT pathway, PIK3CA inhibitor, tumorigenesis on September 24, 2020| Leave a Comment »

Double Mutant PI3KA Found to Lead to Higher Oncogenic Signaling in Cancer Cells

Curator: Stephen J. Williams, PhD

PIK3CA (Phosphatidylinsitol 4,5-bisphosphate (PIP2) 3-kinase catalytic subunit α) is one of the most frequently mutated oncogenes in various tumor types ([1] and http://www.sanger.ac.uk/genetics/CGP/cosmic). Oncogenic mutations leading to the overactivation of PIK3CA, especially in context in of inactivating PTEN mutations, result in overtly high signaling activity and associated with the malignant phenotype.

In a Perspective article (Double trouble for cancer gene: Double mutations in an oncogene enhance tumor growth) in the journal Science[2], Dr. Alex Toker discusses the recent results of Vasan et al. in the same issue of Science[3] on the finding that double mutations in the same allele of PIK3CA are more frequent in cancer genomes than previously identified and these double mutations lead to increased PI3K pathway activation, increased tumor growth, and increased sensitivity to PI3K inhibitors in human breast cancer.

From Dr. Melvin Crasto blog NewDrugApprovals.org

Alpelisib: PIK3CA inhibitor:

Alpelisib: New PIK3CA inhibitor approved for HER2 negative metastatic breast cancer

FDA approves first PI3K inhibitor for breast cancer

syn https://newdrugapprovals.org/2018/06/25/alpelisib-byl-719/

Today, the U.S. Food and Drug Administration approved Piqray (alpelisib) tablets, to be used in combination with the FDA-approved endocrine therapy fulvestrant, to treat postmenopausal women, and men, with hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative, PIK3CA-mutated, advanced or metastatic breast cancer (as detected by an FDA-approved test) following progression on or after an endocrine-based regimen.

The FDA also approved the companion diagnostic test, therascreen PIK3CA RGQ PCR Kit, to detect the PIK3CA mutation in a tissue and/or a liquid biopsy. Patients who are negative by

May 24, 2019

The FDA also approved the companion diagnostic test, therascreen PIK3CA RGQ PCR Kit, to detect the PIK3CA mutation in a tissue and/or a liquid biopsy. Patients who are negative by the therascreen test using the liquid biopsy should undergo tumor biopsy for PIK3CA mutation testing.

“Piqray is the first PI3K inhibitor to demonstrate a clinically meaningful benefit in treating patients with this type of breast cancer. The ability to target treatment to a patient’s specific genetic mutation or biomarker is becoming increasingly common in cancer treatment, and companion diagnostic tests assist oncologists in selecting patients who may benefit from these targeted treatments,” said Richard Pazdur, M.D., director of the FDA’s Oncology Center of Excellence and acting director of the Office of Hematology and Oncology Products in the FDA’s Center for Drug Evaluation and Research. “For this approval, we employed some of our newer regulatory tools to streamline reviews without compromising the quality of our assessment. This drug is the first novel drug approved under the Real-Time Oncology Review pilot program. We also used the updated Assessment Aid, a multidisciplinary review template that helps focus our written review on critical thinking and consistency and reduces time spent on administrative tasks.”

Metastatic breast cancer is breast cancer that has spread beyond the breast to other organs in the body (most often the bones, lungs, liver or brain). When breast cancer is hormone-receptor positive, patients may be treated with anti-hormonal treatment (also called endocrine therapy), alone or in combination with other medicines, or chemotherapy.

The efficacy of Piqray was studied in the SOLAR-1 trial, a randomized trial of 572 postmenopausal women and men with HR-positive, HER2-negative, advanced or metastatic breast cancer whose cancer had progressed while on or after receiving an aromatase inhibitor. Results from the trial showed the addition of Piqray to fulvestrant significantly prolonged progression- free survival (median of 11 months vs. 5.7 months) in patients whose tumors had a PIK3CA mutation.

Common side effects of Piqray are high blood sugar levels, increase in creatinine, diarrhea, rash, decrease in lymphocyte count in the blood, elevated liver enzymes, nausea, fatigue, low red blood cell count, increase in lipase (enzymes released by the pancreas), decreased appetite, stomatitis, vomiting, weight loss, low calcium levels, aPTT prolonged (blood clotting taking longer to occur than it should), and hair loss.

Health care professionals are advised to monitor patients taking Piqray for severe hypersensitivity reactions (intolerance). Patients are warned of potentially severe skin reactions (rashes that may result in peeling and blistering of skin or mucous membranes like the lips and gums). Health care professionals are advised not to initiate treatment in patients with a history of severe skin reactions such as Stevens-Johnson Syndrome, erythema multiforme, or toxic epidermal necrolysis. Patients on Piqray have reported severe hyperglycemia (high blood sugar), and the safety of Piqray in patients with Type 1 or uncontrolled Type 2 diabetes has not been established. Before initiating treatment with Piqray, health care professionals are advised to check fasting glucose and HbA1c, and to optimize glycemic control. Patients should be monitored for pneumonitis/interstitial lung disease (inflammation of lung tissue) and diarrhea during treatment. Piqray must be dispensed with a patient Medication Guide that describes important information about the drug’s uses and risks.

Piqray is the first new drug application (NDA) for a new molecular entity approved under the Real-Time Oncology Review (RTOR) pilot program, which permits the FDA to begin analyzing key efficacy and safety datasets prior to the official submission of an application, allowing the review team to begin their review and communicate with the applicant earlier. Piqray also used the updated Assessment Aid (AAid), a multidisciplinary review template intended to focus the FDA’s written review on critical thinking and consistency and reduce time spent on administrative tasks. With these two pilot programs, today’s approval of Piqray comes approximately three months ahead of the Prescription Drug User Fee Act (PDUFA) VI deadline of August 18, 2019.

The FDA granted this application Priority Review designation. The FDA granted approval of Piqray to Novartis. The FDA granted approval of the therascreen PIK3CA RGQ PCR Kit to QIAGEN Manchester, Ltd.

https://www.fda.gov/news-events/press-announcements/fda-approves-first-pi3k-inhibitor-breast-cancer?utm_campaign=052419_PR_FDA%20approves%20first%20PI3K%20inhibitor%20for%20breast%20cancer&utm_medium=email&utm_source=Eloqua

Alpelisib

(2S)-1-N-[4-methyl-5-[2-(1,1,1-trifluoro-2-methylpropan-2-yl)pyridin-4-yl]-1,3-thiazol-2-yl]pyrrolidine-1,2-dicarboxamide

PDT PAT WO 2010/029082

CHEMICAL NAMES:	Alpelisib; CAS 1217486-61-7; BYL-719; BYL719; UNII-08W5N2C97Q; BYL 719
MOLECULAR FORMULA:	C₁₉H₂₂F₃N₅O₂S
MOLECULAR WEIGHT:	441.473 g/mol

Alpelisib is an orally bioavailable phosphatidylinositol 3-kinase (PI3K) inhibitor with potential antineoplastic activity. Alpelisib specifically inhibits PI3K in the PI3K/AKT kinase (or protein kinase B) signaling pathway, thereby inhibiting the activation of the PI3K signaling pathway. This may result in inhibition of tumor cell growth and survival in susceptible tumor cell populations. Activation of the PI3K signaling pathway is frequently associated with tumorigenesis. Dysregulated PI3K signaling may contribute to tumor resistance to a variety of antineoplastic agents.

Alpelisib has been used in trials studying the treatment and basic science of Neoplasms, Solid Tumors, BREAST CANCER, 3rd Line GIST, and Rectal Cancer, among others.

SYN 2

POLYMORPHS

https://patents.google.com/patent/WO2012175522A1/en

(S)-pyrrolidine-l,2-dicarboxylic acid 2-amide l-(4-methyl-5-[2-(2,2,2-trifluoro-l,l- dimethyl-ethyl)-pyridin-4-yl]-thiazol-2-yl)-amidei hereafter referred to as compound I,

is an alpha-selective phosphatidylinositol 3 -kinase (PI3K) inhibitor. Compound I was originally described in WO 2010/029082, wherein the synthesis of its free base form was described. There is a need for additional solid forms of compound I, for use in drug substance and drug product development. It has been found that new solid forms of compound I can be prepared as one or more polymorph forms, including solvate forms. These polymorph forms exhibit new physical properties that may be exploited in order to obtain new pharmacological properties, and that may be utilized in drug substance and drug product development. Summary of the Invention

In one aspect, provided herein is a crystalline form of the compound of formula I, or a solvate of the crystalline form of the compound of formula I, or a salt of the crystalline form of the compound of formula I, or a solvate of a salt of the crystalline form of the compound of formula I. In one embodiment, the crystalline form of the compound of formula I has the polymorph form S_A, S_B, Sc, or S_D.

In another aspect, provided herein is a pharmaceutical composition comprising a crystalline compound of formula I. In one embodiment of the pharmaceutical composition, the crystalline compound of formula I has the polymorph form S_A, SB_,S_c, or So.

In another aspect, provided herein is a method for the treatment of disorders mediated by PI3K, comprising administering to a patient in need of such treatment an effective amount of a crystalline compound of formula I, particularly S_A, S_B, S_C,or S_D .

In yet another aspect, provided herein is the use of a crystalline compound of formula I, particularly S_A, S_B, S_C, or S_D, for the preparation of a medicament for the treatment of disorders mediated by PI3K.

Source: https://newdrugapprovals.org/?s=alpelisib&submit=

Pharmacology and Toxicology from drugbank.ca

Indication

Alpelisib is indicated in combination with fulvestrant to treat postmenopausal women, and men, with advanced or metastatic breast cancer.^Label This cancer must be hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative, and PIK3CA mutated.^Label The cancer must be detected by an FDA-approved test following progression on or after an endocrine-based regimen.^Label

Associated Conditions

Advanced Metastatic Breast Cancer

Contraindications & Blackbox Warnings

Learn about our commercial Contraindications & Blackbox Warnings data.

LEARN MORE

Pharmacodynamics

Alpelisib does not prolong the QTcF interval.^Label Patients taking alpelisib experience a dose dependent benefit from treatment with a 51% advantage of a 200mg daily dose over a 100mg dose and a 22% advantage of 300mg once daily over 150mg twice daily.⁶ This suggests patients requiring a lower dose may benefit from twice daily dosing.⁶

Mechanism of action

Phosphatidylinositol-3-kinase-α (PI3Kα) is responsible for cell proliferation in response to growth factor-tyrosine kinase pathway activation.³ In some cancers PI3Kα’s p110α catalytic subunit is mutated making it hyperactive.³ Alpelisib inhibits (PI3K), with the highest specificity for PI3Kα.^Label

TARGET	ACTIONS	ORGANISM
APhosphatidylinositol 4,5-bisphosphate 3-kinase catalytic subunit alpha isoform	inhibitor	Humans

Absorption

Alpelisib reached a peak concentration in plasma of 1320±912ng/mL after 2 hours.⁴ Alpelisib has an AUC_last of 11,100±3760h ng/mL and an AUC_INF of 11,100±3770h ng/mL.⁴ A large, high fat meal increases the AUC by 73% and C_max by 84% while a small, low fat meal increases the AUC by 77% and C_max by 145%.^Label

Volume of distribution

The apparent volume of distribution at steady state is 114L.^Label

Protein binding

Alpelisib is 89% protein bound.^Label

Metabolism

Alpelisib is metabolized by hydrolysis reactions to form the primary metabolite.^Label It is also metabolized by CYP3A4.^Label The full metabolism of Alpelisib has yet to be determined but a series of reactions have been proposed.⁴^,⁵ The main metabolic reaction is the substitution of an amine group on alpelisib for a hydroxyl group to form a metabolite known as M4⁴^,⁵ or BZG791.^Label Alpelisib can also be glucuronidated to form the M1 and M12 metabolites.⁴^,⁵

Hover over products below to view reaction partners

Alpelisib
- Alpelisib M4 Metabolite

Route of elimination

36% of an oral dose is eliminated as unchanged drug in the feces and 32% as the primary metabolite BZG791 in the feces.^Label 2% of an oral dose is eliminated in the urine as unchanged drug and 7.1% as the primary metabolite BZG791.^Label In total 81% of an oral dose is eliminated in the feces and 14% is eliminated in the urine.^Label

Half-life

The mean half life of alprelisib is 8 to 9 hours.^Label

Clearance

The mean apparent oral clearance was 39.0L/h.⁴ The predicted clearance is 9.2L/hr under fed conditions.^Label

Adverse Effects

Learn about our commercial Adverse Effects data.

LEARN MORE

Toxicity

LD₅₀ and Overdose

Patients experiencing an overdose may present with hyperglycemia, nausea, asthenia, and rash.^Label There is no antidote for an overdose of alpelisib so patients should be treated symptomatically.^Label Data regarding an LD₅₀ is not readily available.^MSDS In clinical trials, patients were given doses of up to 450mg once daily.^Label

Pregnancy, Lactation, and Fertility

Following administration in rats and rabbits during organogenesis, adverse effects on the reproductive system, such as embryo-fetal mortality, reduced fetal weights, and increased incidences of fetal malformations, were observed.^Label Based on these findings of animals studies and its mechanism of action, it is proposed that alpelisib may cause embryo-fetal toxicity when administered to pregnant patients.^Label There is no data available regarding the presence of alpelisib in breast milk so breast feeding mothers are advised not to breastfeed while taking this medication and for 1 week after their last dose.^Label Based on animal studies, alpelisib may impair fertility of humans.^Label

Carcinogenicity and Mutagenicity

Studies of carcinogenicity have yet to be performed.^Label Alpelisib has not been found to be mutagenic in the Ames test.^Label It is not aneugenic, clastogenic, or genotoxic in further assays.^Label

Affected organisms

Not Available

Pathways

Not Available

Pharmacogenomic Effects/ADRs

Not Available

Source: https://www.drugbank.ca/drugs/DB12015

References

Yuan TL, Cantley LC: PI3K pathway alterations in cancer: variations on a theme. Oncogene 2008, 27(41):5497-5510.
Toker A: Double trouble for cancer gene. Science 2019, 366(6466):685-686.
Vasan N, Razavi P, Johnson JL, Shao H, Shah H, Antoine A, Ladewig E, Gorelick A, Lin TY, Toska E et al: Double PIK3CA mutations in cis increase oncogenicity and sensitivity to PI3Kalpha inhibitors. Science 2019, 366(6466):714-723.

Read Full Post »

RNA from the SARS-CoV-2 virus taking over the cells it infects: Virulence – Pathogen’s ability to infect a Resistant Host: The Imbalance between Controlling virus Replication versus Activation of the Adaptive Immune Response

Posted in Antibody Responses Predict Antigen Exposure, Apoptosis, Autophagy-Modulating Proteins, Cell Biology, Signaling & Cell Circuits, Coronavirus Gene Expression, COVID-19, Cytokine Receptor Structure, Genome Biology, Human Antibody Response, Human Circulating Antibody Repertoire, Human Naive B Cell Repertoire, Immunology, Immunotherapy, Infectious Disease & New Antibiotic Targets, Infectious Disease Immunodiagnostics, Innovation in Immunology Diagnostics, MHC Repertoires for Antigen Prediction, mRNA Therapeutics, Population Health Management, Genetics & Pharmaceutical, SARS-CoV-2, Serology tests for coronavirus antibodies, Single Cell Genomics, Single-cell sequencing, Synthetic Immunology: Hacking Immune Cells, Vaccinology, Variation in human protein-coding regions, Viral diseases, Virology - Vector-borne DIsease, Virus Infective Acute Respiratory Syndrome: SARS-CoV on May 23, 2020| Leave a Comment »

RNA from the SARS-CoV-2 virus taking over the cells it infects: Virulence – Pathogen’s ability to infect a Resistant Host: The Imbalance between Controlling Virus Replication versus Activation of the Adaptive Immune Response

Curator: Aviva Lev-Ari, PhD, RN – I added colors and bold face

UPDATED on 9/8/2020

What bats can teach us about developing immunity to Covid-19 | Free to read

Clive Cookson, Anna Gross and Ian Bott, London

https://www.ft.com/content/743ce7a0-60eb-482d-b1f4-d4de11182fa9?utm_source=Nature+Briefing&utm_campaign=af64422080-briefing-dy-20200908&utm_medium=email&utm_term=0_c9dfd39373-af64422080-43323101

UPDATED on 6/29/2020

Another duality and paradox in the Treatment of COVID-19 Patients in ICUs was expressed by Mike Yoffe, MD, PhD, David H. Koch Professor of Biology and Biological Engineering, Massachusetts Institute of Technology. Dr. Yaffe has a joint appointment in Acute Care Surgery, Trauma, and Surgical Critical Care, and in Surgical Oncology @BIDMC

on 6/29 at SOLUTIONS with/in/sight at Koch Institute @MIT

How Are Cancer Researchers Fighting COVID-19? (Part II)” Jun 29, 2020 11:30 AM EST

Mike Yoffe, MD, PhD

In COVID-19 patients: two life threatening conditions are seen in ICUs:

Blood Clotting – Hypercoagulability or Thrombophilia

Cytokine Storm – immuno-inflammatory response

The coexistence of 1 and 2 – HINDERS the ability to use effectively tPA as an anti-clotting agent while the cytokine storm is present.

Mike Yoffe’s related domain of expertise:

Signaling pathways and networks that control cytokine responses and inflammation

Misregulation of cytokine feedback loops, along with inappropriate activation of the blood clotting cascade causes dysregulation of cell signaling pathways in innate immune cells (neutrophils and macrophages), resulting in tissue damage and multiple organ failure following trauma or sepsis. Our research is focused on understanding the role of the p38-MK2 pathway in cytokine control and innate immune function, and on cross-talk between cytokines, clotting factors, and neutrophil NADPH oxidase-derived ROS in tissue damage, coagulopathy, and inflammation, using biochemistry, cell biology, and mouse knock-out/knock-in models. We recently discovered a particularly important link between abnormal blood clotting and the complement pathway cytokine C5a which causes excessive production of extracellular ROS and organ damage by neutrophils after traumatic injury.

SOURCE

https://www.bidmc.org/research/research-by-department/surgery/acute-care-surgery-trauma-and-surgical-critical-care/michael-b-yaffe

See

The Genome Structure of CORONAVIRUS, SARS-CoV-2

Reporter: Aviva Lev-Ari, PhD, RN

https://pharmaceuticalintelligence.com/2020/05/04/the-genome-structure-of-coronavirus-sars-cov-2-i-awaited-for-this-article-for-60-days/

Imbalanced Host Response to SARS-CoV-2 Drives Development of COVID-19

Open Access Published:May 15, 2020DOI:https://doi.org/10.1016/j.cell.2020.04.026

Highlights

SARS-CoV-2 infection induces low IFN-I and -III levels with a moderate ISG response

Strong chemokine expression is consistent across in vitro, ex vivo, and in vivo models

Low innate antiviral defenses and high pro-inflammatory cues contribute to COVID-19

Summary

Viral pandemics, such as the one caused by SARS-CoV-2, pose an imminent threat to humanity. Because of its recent emergence, there is a paucity of information regarding viral behavior and host response following SARS-CoV-2 infection. Here we offer an in-depth analysis of the transcriptional response to SARS-CoV-2 compared with other respiratory viruses. Cell and animal models of SARS-CoV-2 infection, in addition to transcriptional and serum profiling of COVID-19 patients, consistently revealed a unique and inappropriate inflammatory response. This response is defined by low levels of type I and III interferons juxtaposed to elevated chemokines and high expression of IL-6. We propose that reduced innate antiviral defenses coupled with exuberant inflammatory cytokine production are the defining and driving features of COVID-19.

Graphical Abstract

View Large Image

Figure Viewer

Download Hi-res image

Download (PPT)

Keywords

SARS-CoV-2

COVID-19

interferon

Coronavirus

transcriptomics

virus-host interactions

chemokines

IL6

ferret

Results

Defining the Transcriptional Response to SARS-CoV-2 Relative to Other Respiratory Viruses

To compare the transcriptional response of SARS-CoV-2 with other respiratory viruses, including MERS-CoV, SARS-CoV-1, human parainfluenza virus 3 (HPIV3), respiratory syncytial virus (RSV), and IAV, we first chose to focus on infection in a variety of respiratory cell lines (Figure 1). To this end, we collected poly(A) RNA from infected cells and performed RNA sequencing (RNA-seq) to estimate viral load. These data show that virus infection levels ranged from 0.1% to more than 50% of total RNA reads (Figure 1A).

Discussion

In the present study, we focus on defining the host response to SARS-CoV-2 and other human respiratory viruses in cell lines, primary cell cultures, ferrets, and COVID-19 patients. In general, our data show that the overall transcriptional footprint of SARS-CoV-2 infection was distinct in comparison with other highly pathogenic coronaviruses and common respiratory viruses such as IAV, HPIV3, and RSV. It is noteworthy that, despite a reduced IFN-I and -III response to SARS-CoV-2, we observed a consistent chemokine signature. One exception to this observation is the response to high-MOI infection in A549-ACE2 and Calu-3 cells, where replication was robust and an IFN-I and -III signature could be observed. In both of these examples, cells were infected at a rate to theoretically deliver two functional virions per cell in addition to any defective interfering particles within the virus stock that were not accounted for by plaque assays. Under these conditions, the threshold for PAMP may be achieved prior to the ability of the virus to evade detection through production of a viral antagonist. Alternatively, addition of multiple genomes to a single cell may disrupt the stoichiometry of viral components, which, in turn, may itself generate PAMPs that would not form otherwise. These ideas are supported by the fact that, at a low-MOI infection in A549-ACE2 cells, high levels of replication could also be achieved, but in the absence of IFN-I and -III induction. Taken together, these data suggest that, at low MOIs, the virus is not a strong inducer of the IFN-I and -III system, as opposed to conditions where the MOI is high.

Taken together, the data presented here suggest that the response to SARS-CoV-2 is imbalanced with regard to controlling virus replication versus activation of the adaptive immune response. Given this dynamic, treatments for COVID-19 have less to do with the IFN response and more to do with controlling inflammation. Because our data suggest that numerous chemokines and ILs are elevated in COVID-19 patients, future efforts should focus on U.S. Food and Drug Administration (FDA)-approved drugs that can be rapidly deployed and have immunomodulating properties.

SARS-CoV-2 Cell Entry Depends on ACE2 and TMPRSS2 and Is Blocked by a Clinically Proven Protease Inhibitor
Hoffmann et al.

CellMarch 05, 2020
- In Brief
- Full-Text
- PDF
Open Access
Structural and Functional Basis of SARS-CoV-2 Entry by Using Human ACE2
Wang et al.

CellApril 09, 2020
- In Brief
- Full-Text
- PDF
Open Access
Inhibition of SARS-CoV-2 Infections in Engineered Human Tissues Using Clinical-Grade Soluble Human ACE2
Monteil et al.

CellApril 24, 2020
- In Brief
- Full-Text
- PDF
Open Access
Targets of T cell responses to SARS-CoV-2 coronavirus in humans with COVID-19 disease and unexposed individuals
Grifoni et al.

CellMay 14, 2020
- In Brief
- Full-Text
- PDF
Structure, Function, and Antigenicity of the SARS-CoV-2 Spike Glycoprotein
Walls et al.

CellMarch 09, 2020
- In Brief
- Full-Text
- PDF
Open Access

SOURCE

https://www.cell.com/cell/fulltext/S0092-8674(20)30489-X

SARS-CoV-2 ORF3b is a potent interferon antagonist whose activity is further increased by a naturally occurring elongation variant

, Izumi Kimura, Keiya Uriu, Masaya Fukushi, Takashi Irie, Yoshio Koyanagi, So Nakagawa, Kei Sato

doi: https://doi.org/10.1101/2020.05.11.088179

Abstract

One of the features distinguishing SARS-CoV-2 from its more pathogenic counterpart SARS-CoV is the presence of premature stop codons in its ORF3b gene. Here, we show that SARS-CoV-2 ORF3b is a potent interferon antagonist, suppressing the induction of type I interferon more efficiently than its SARS-CoV ortholog. Phylogenetic analyses and functional assays revealed that SARS-CoV-2-related viruses from bats and pangolins also encode truncated ORF3b gene products with strong anti-interferon activity. Furthermore, analyses of more than 15,000 SARS-CoV-2 sequences identified a natural variant, in which a longer ORF3b reading frame was reconstituted. This variant was isolated from two patients with severe disease and further increased the ability of ORF3b to suppress interferon induction. Thus, our findings not only help to explain the poor interferon response in COVID-19 patients, but also describe a possibility of the emergence of natural SARS-CoV-2 quasi-species with extended ORF3b that may exacerbate COVID-19 symptoms.

Highlights

ORF3b of SARS-CoV-2 and related bat and pangolin viruses is a potent IFN antagonist

SARS-CoV-2 ORF3b suppresses IFN induction more efficiently than SARS-CoV ortholog

The anti-IFN activity of ORF3b depends on the length of its C-terminus

An ORF3b with increased IFN antagonism was isolated from two severe COVID-19 cases

Competing Interest Statement

The authors have declared no competing interest.

Paper in collection COVID-19 SARS-CoV-2 preprints from medRxiv and bioRxiv

SOURCE

https://www.biorxiv.org/content/10.1101/2020.05.11.088179v1

‘It’s something I have never seen’: How the Covid-19 virus hijacks cells

By SHARON BEGLEY @sxbegle

MAY 21, 2020

RNA (in green) from the SARS-CoV-2 virus is shown taking over the cells it infects.ICAHN SCHOOL OF MEDICINE AT MOUNT SINAI

A deep dive into how the new coronavirus infects cells has found that it orchestrates a hostile takeover of their genes unlike any other known viruses do, producing what one leading scientist calls “unique” and “aberrant” changes.Recent studies show that in seizing control of genes in the human cells it invades, the virus changes how segments of DNA are read, doing so in a way that might explain why the elderly are more likely to die of Covid-19 and why antiviral drugs might not only save sick patients’ lives but also prevent severe disease if taken before infection.“It’s something I have never seen in my 20 years of” studying viruses, said virologist Benjamin tenOever of the Icahn School of Medicine at Mount Sinai, referring to how SARS-CoV-2, the virus that causes Covid-19, hijacks cells’ genomes.The “something” he and his colleagues saw is how SARS-CoV-2 blocks one virus-fighting set of genes but allows another set to launch, a pattern never seen with other viruses. Influenza and the original SARS virus (in the early 2000s), for instance, interfere with both arms of the body’s immune response — what tenOever dubs “call to arms” genes and “call for reinforcement” genes.The first group of genes produces interferons. These proteins, which infected cells release, are biological semaphores, signaling to neighboring cells to activate some 500 of their own genes that will slow down the virus’ ability to make millions of copies of itself if it invades them. This lasts seven to 10 days, tenOever said, controlling virus replication and thereby buying time for the second group of genes to act.This second set of genes produce their own secreted proteins, called chemokines, that emit a biochemical “come here!” alarm. When far-flung antibody-making B cells and virus-killing T cells sense the alarm, they race to its source. If all goes well, the first set of genes holds the virus at bay long enough for the lethal professional killers to arrive and start eradicating viruses.

“Most other viruses interfere with some aspect of both the call to arms and the call for reinforcements,” tenOever said. “If they didn’t, no one would ever get a viral illness”: The one-two punch would pummel any incipient infection into submission.

SARS-CoV-2, however, uniquely blocks one cellular defense but activates the other, he and his colleagues reported in a study published last week in Cell. They studied healthy human lung cells growing in lab dishes, ferrets (which the virus infects easily), and lung cells from Covid-19 patients. In all three, they found that within three days of infection, the virus induces cells’ call-for-reinforcement genes to produce cytokines. But it blocks their call-to-arms genes — the interferons that dampen the virus’ replication.

The result is essentially no brakes on the virus’s replication, but a storm of inflammatory molecules in the lungs, which is what tenOever calls an “unique” and “aberrant” consequence of how SARS-CoV-2 manipulates the genome of its target.

In another new study, scientists in Japan last week identified how SARS-CoV-2 accomplishes that genetic manipulation. Its ORF3b gene produces a protein called a transcription factor that has “strong anti-interferon activity,” Kei Sato of the University of Tokyo and colleagues found — stronger than the original SARS virus or influenza viruses. The protein basically blocks the cell from recognizing that a virus is present, in a way that prevents interferon genes from being expressed.

In fact, the Icahn School team found no interferons in the lung cells of Covid-19 patients. Without interferons, tenOever said, “there is nothing to stop the virus from replicating and festering in the lungs forever.”

That causes lung cells to emit even more “call-for-reinforcement” genes, summoning more and more immune cells. Now the lungs have macrophages and neutrophils and other immune cells “everywhere,” tenOever said, causing such runaway inflammation “that you start having inflammation that induces more inflammation.”

At the same time, unchecked viral replication kills lung cells involved in oxygen exchange. “And suddenly you’re in the hospital in severe respiratory distress,” he said.

In elderly people, as well as those with diabetes, heart disease, and other underlying conditions, the call-to-arms part of the immune system is weaker than in younger, healthier people, even before the coronavirus arrives. That reduces even further the cells’ ability to knock down virus replication with interferons, and imbalances the immune system toward the dangerous inflammatory response.

The discovery that SARS-CoV-2 strongly suppresses infected cells’ production of interferons has raised an intriguing possibility: that taking interferons might prevent severe Covid-19 or even prevent it in the first place, said Vineet Menachery of the University of Texas Medical Branch.

In a study of human cells growing in lab dishes, described in a preprint (not peer-reviewed or published in a journal yet), he and his colleagues also found that SARS-CoV-2 “prevents the vast amount” of interferon genes from turning on. But when cells growing in lab dishes received the interferon IFN-1 before exposure to the coronavirus, “the virus has a difficult time replicating.”

After a few days, the amount of virus in infected but interferon-treated cells was 1,000- to 10,000-fold lower than in infected cells not pre-treated with interferon. (The original SARS virus, in contrast, is insensitive to interferon.)

Ending the pandemic and preventing its return is assumed to require an effective vaccine to prevent infectionand antiviral drugs such as remdesivir to treat the very sick, but the genetic studies suggest a third strategy: preventive drugs.

It’s possible that treatment with so-called type-1 interferon “could stop the virus before it could get established,” Menachery said.

Giving drugs to healthy people is always a dicey proposition, since all drugs have side effects — something considered less acceptable than when a drug is used to treat an illness. “Interferon treatment is rife with complications,” Menachery warned. The various interferons, which are prescribed for hepatitis, cancers, and many other diseases, can cause flu-like symptoms.

But the risk-benefit equation might shift, both for individuals and for society, if interferons or antivirals or other medications are shown to reduce the risk of developing serious Covid-19 or even make any infection nearly asymptomatic.

Interferon “would be warning the cells the virus is coming,” Menachery said, so such pretreatment might “allow treated cells to fend off the virus better and limit its spread.” Determining that will of course require clinical trials, which are underway.

About the Author

Sharon Begley

Senior Writer, Science and Discovery

sharon.begley@statnews.com

@sxbegle

SOURCE

https://www.statnews.com/2020/05/21/coronavirus-hijacks-cells-in-unique-ways/?utm_source=STAT+Newsletters&utm_campaign=bee97f4883-Daily_Recap&utm_medium=email&utm_term=0_8cab1d7961-bee97f4883-150237109

An Intelligent DNA Nanorobot to Fight Cancer by Targeting HER2 Expression

Posted in Apoptosis, BioIT: BioInformatics, NGS, Clinical & Translational, Pharmaceutical R&D Informatics, Clinical Genomics, Cancer Informatics, Biological Networks, Breast Cancer - impalpable breast lesions, Cancer - General, Cancer and Current Therapeutics, CANCER BIOLOGY & Innovations in Cancer Therapy, Cancer Genomics, cancer metabolism, Cancer Prevention: Research & Programs, Cancer Screening, Cancer Vaccines: Targeting Cancer Genes for Immunotherapy, Cancer-Immune Interactions, Cell Biology, Cell Biology, Signaling & Cell Circuits, Metabolic Immuno-Oncology, Monoclonal Immunotherapy, Oligonucleotide Therapeutics & Delivery, Precision Cancer Medicine, RNA Biology, Cancer and Therapeutics, Signaling & Cell Circuits, tagged Cancer, gene expression, HApt, HER2, Nanorobot, tFNA, Therapy on July 24, 2019| Leave a Comment »

An Intelligent DNA Nanorobot to Fight Cancer by Targeting HER2 Expression

Reporter and Curator: Dr. Sudipta Saha, Ph.D.

3.2.9

3.2.9 An Intelligent DNA Nanorobot to Fight Cancer by Targeting HER2 Expression, Volume 2 (Volume Two: Latest in Genomics Methodologies for Therapeutics: Gene Editing, NGS and BioInformatics, Simulations and the Genome Ontology), Part 2: CRISPR for Gene Editing and DNA Repair

HER2 is an important prognostic biomarker for 20–30% of breast cancers, which is the most common cancer in women. Overexpression of the HER2 receptor stimulates breast cells to proliferate and differentiate uncontrollably, thereby enhancing the malignancy of breast cancer and resulting in a poor prognosis for affected individuals. Current therapies to suppress the overexpression of HER2 in breast cancer mainly involve treatment with HER2-specific monoclonal antibodies. However, these monoclonal anti-HER2 antibodies have severe side effects in clinical trials, such as diarrhea, abnormal liver function, and drug resistance. Removing HER2 from the plasma membrane or inhibiting the gene expression of HER2 is a promising alternative that could limit the malignancy of HER2-positive cancer cells.

DNA origami is an emerging field of DNA-based nanotechnology and intelligent DNA nanorobots show great promise in working as a drug delivery system in healthcare. Different DNA-based nanorobots have been developed as affordable and facile therapeutic drugs. In particular, many studies reported that a tetrahedral framework nucleic acid (tFNA) could serve as a promising DNA nanocarrier for many antitumor drugs, owing to its high biocompatibility and biosecurity. For example, tFNA was reported to effectively deliver paclitaxel or doxorubicin to cancer cells for reversing drug resistance, small interfering RNAs (siRNAs) have been modified into tFNA for targeted drug delivery. Moreover, the production and storage of tFNA are not complicated, and they can be quickly degraded in lysosomes by cells. Since both free HApt and tFNA can be diverted into lysosomes, so, combining the HApt and tFNA as a novel DNA nanorobot (namely, HApt-tFNA) can be an effective strategy to improve its delivery and therapeutic efficacy in treating HER2-positive breast cancer.

Researchers reported that a DNA framework-based intelligent DNA nanorobot for selective lysosomal degradation of tumor-specific proteins on cancer cells. An anti-HER2 aptamer (HApt) was site-specifically anchored on a tetrahedral framework nucleic acid (tFNA). This DNA nanorobot (HApt-tFNA) could target HER2-positive breast cancer cells and specifically induce the lysosomal degradation of the membrane protein HER2. An injection of the DNA nanorobot into a mouse model revealed that the presence of tFNA enhanced the stability and prolonged the blood circulation time of HApt, and HApt-tFNA could therefore drive HER2 into lysosomal degradation with a higher efficiency. The formation of the HER2-HApt-tFNA complexes resulted in the HER2-mediated endocytosis and digestion in lysosomes, which effectively reduced the amount of HER2 on the cell surfaces. An increased HER2 digestion through HApt-tFNA further induced cell apoptosis and arrested cell growth. Hence, this novel DNA nanorobot sheds new light on targeted protein degradation for precision breast cancer therapy.

It was previously reported that tFNA was degraded by lysosomes and could enhance cell autophagy. Results indicated that free Cy5-HApt and Cy5-HApt-tFNA could enter the lysosomes; thus, tFNA can be regarded as an efficient nanocarrier to transmit HApt into the target organelle. The DNA nanorobot composed of HApt and tFNA showed a higher stability and a more effective performance than free HApt against HER2-positive breast cancer cells. The PI3K/AKT pathway was inhibited when membrane-bound HER2 decreased in SK-BR-3 cells under the action of HApt-tFNA. The research findings suggest that tFNA can enhance the anticancer effects of HApt on SK-BR-3 cells; while HApt-tFNA can bind to HER2 specifically, the compounded HER2-HApt-tFNA complexes can then be transferred and degraded in lysosomes. After these processes, the accumulation of HER2 in the plasma membrane would decrease, which could also influence the downstream PI3K/AKT signaling pathway that is associated with cell growth and death.

However, some limitations need to be noted when interpreting the findings: (i) the cytotoxicity of the nanorobot on HER2-positive cancer cells was weak, and the anticancer effects between conventional monoclonal antibodies and HApt-tFNA was not compared; (ii) the differences in delivery efficiency between tFNA and other nanocarriers need to be confirmed; and (iii) the confirmation of anticancer effects of HApt-tFNA on tumors within animals remains challenging. Despite these limitations, the present study provided novel evidence of the biological effects of tFNA when combined with HApt. Although the stability and the anticancer effects of HApt-tFNA may require further improvement before clinical application, this study initiates a promising step toward the development of nanomedicines with novel and intelligent DNA nanorobots for tumor treatment.

References:

https://pubs.acs.org/doi/10.1021/acs.nanolett.9b01320

https://www.ncbi.nlm.nih.gov/pubmed/27939064

https://www.ncbi.nlm.nih.gov/pubmed/11694782

https://www.ncbi.nlm.nih.gov/pubmed/27082923

https://www.ncbi.nlm.nih.gov/pubmed/25365825

https://www.ncbi.nlm.nih.gov/pubmed/26840503

https://www.ncbi.nlm.nih.gov/pubmed/29802035

Read Full Post »

Immunoediting can be a constant defense in the cancer landscape

Posted in Anticancer Resistance, Apoptosis, BioIT: BioInformatics, NGS, Clinical & Translational, Pharmaceutical R&D Informatics, Clinical Genomics, Cancer Informatics, Breast Cancer - impalpable breast lesions, Cancer - General, Cancer and Current Therapeutics, CANCER BIOLOGY & Innovations in Cancer Therapy, Cancer Genomics, Cancer Informatics, cancer metabolism, Cancer Prevention: Research & Programs, Cancer Screening, Cancer Surgery of the Heart, Cancer Vaccines: Targeting Cancer Genes for Immunotherapy, Cancer-Immune Interactions, Cell Biology, Cell Biology, Signaling & Cell Circuits, Cell death pathways, Cell Processing System in Cell Therapy Process Development, cell-based therapy, Childhood cancer, Circulating Tumor Cells (CTC), combination immunotherapies., Efficacy of Anti-Tumor T Cells, Engineering Better T Cells, Engineering Enhanced Cancer Vaccines, Funding Opportunities for Cancer Research, Human Immune System in Health and in Disease, Imaging-based Cancer Patient Management, Immune Modulatory, Immuno-Oncology & Genomics, Immunology, Immunotherapy, Infectious Disease Immunodiagnostics, Innovation in Immunology Diagnostics, Integrin-targeted Combination Immunotherapy, Liquid Biopsy Chip detects an array of metastatic cancer cell markers in blood, Liquid Biopsy: Circulating Tumor Cells in Urine and Blood, Metabolic Immuno-Oncology, Microbiome and Responses to Cancer Therapy, MicroEngineering Cell-Tissue & Systems, Modulating Macrophages in Cancer Immunotherapy, Monoclonal Immunotherapy, NK Cell-Based Cancer Immunotherapy, Pancreatic cancer, Pharmacotherapy and Cell Activity, Population Health Management, Population Health Management, Genetics & Pharmaceutical, Population Health Management, Nutrition and Phytochemistry, Precision Cancer Medicine, Prostate Cancer: Monitoring vs Treatment, RNA Biology, Cancer and Therapeutics, Signaling & Cell Circuits, Single Cell Genomics, stem cell biology and patient-specific, Stem Cells for Regenerative Medicine, Synergistic Innate and Adaptive Immunotherapy, Synthetic Immunology: Hacking Immune Cells, Universal Immune Cell Therapies (uICT), Voices of Patients and Healthcare Providers, tagged Cancer, cancer vaccine, DNA, HLA, immunoediting on March 16, 2019| Leave a Comment »

Reporter and Curator: Dr. Sudipta Saha, Ph.D.

There are many considerations in the cancer immunoediting landscape of defense and regulation in the cancer hallmark biology. The cancer hallmark biology in concert with key controls of the HLA compatibility affinity mechanisms are pivotal in architecting a unique patient-centric therapeutic application. Selection of random immune products including neoantigens, antigens, antibodies and other vital immune elements creates a high level of uncertainty and risk of undesirable immune reactions. Immunoediting is a constant process. The human innate and adaptive forces can either trigger favorable or unfavorable immunoediting features. Cancer is a multi-disease entity. There are multi-factorial initiators in a certain disease process. Namely, environmental exposures, viral and / or microbiome exposure disequilibrium, direct harm to DNA, poor immune adaptability, inherent risk and an individual’s own vibration rhythm in life.

When a human single cell is crippled (Deranged DNA) with mixed up molecular behavior that is the initiator of the problem. A once normal cell now transitioned into full threatening molecular time bomb. In the modeling and creation of a tumor it all begins with the singular molecular crisis and crippling of a normal human cell. At this point it is either chop suey (mixed bit responses) or a productive defensive and regulation response and posture of the immune system. Mixed bits of normal DNA, cancer-laden DNA, circulating tumor DNA, circulating normal cells, circulating tumor cells, circulating immune defense cells, circulating immune inflammatory cells forming a moiety of normal and a moiety of mess. The challenge is to scavenge the mess and amplify the normal.

Immunoediting is a primary push-button feature that is definitely required to be hit when it comes to initiating immune defenses against cancer and an adaptation in favor of regression. As mentioned before that the tumor microenvironment is a “mixed bit” moiety, which includes elements of the immune system that can defend against circulating cancer cells and tumor growth. Personalized (Precision-Based) cancer vaccines must become the primary form of treatment in this case. Current treatment regimens in conventional therapy destroy immune defenses and regulation and create more serious complications observed in tumor progression, metastasis and survival. Commonly resistance to chemotherapeutic agents is observed. These personalized treatments will be developed in concert with cancer hallmark analytics and immunocentrics affinity and selection mapping. This mapping will demonstrate molecular pathway interface and HLA compatibility and adaptation with patientcentricity.

References:

https://www.linkedin.com/pulse/immunoediting-cancer-landscape-john-catanzaro/

https://www.cell.com/cell/fulltext/S0092-8674(16)31609-9

https://www.researchgate.net/publication/309432057_Circulating_tumor_cell_clusters_What_we_know_and_what_we_expect_Review

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4190561/

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5840207/

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5593672/

https://www.frontiersin.org/articles/10.3389/fimmu.2018.00414/full

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5593672/

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4190561/

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4388310/

https://www.linkedin.com/pulse/cancer-hallmark-analytics-omics-data-pathway-studio-review-catanzaro/

Read Full Post »

Live 12:00 – 1:00 P.M Mediterranean Diet and Lifestyle: A Symposium on Diet and Human Health : October 19, 2018

Posted in Apoptosis, Biological Networks, Gene Regulation and Evolution, Cancer - General, Cancer and Current Therapeutics, Epigenetics and Cardiovascular Risks, Epigenetics and Environmental Factors, Genomic Expression, Health Economics and Outcomes Research, Heart and Brain Disease in Women, Immune Modulatory, interventional oncology, Left Main Coronary Artery Disease (LMCAD), Li-fraumeni syndrome., Micronutrients, Nutrigenomics, Nutritional Supplements: Atherogenesis, Obesity, Pharmacotherapy of Cardiovascular Disease, REAL TIME Conference Coverage Twitter's Hashtags and Handles per Presentation/session, Scientific & Biotech Conferences: Press Coverage, TP53 - Germline mutations, Uncategorized, tagged application to nutrition, Cancer, cancer prevention, Diabetes, diet, disease prevention, environment, Epidemiology, epigenetic, gastric cancer, healthcare, healthy eating, mediteranean diet, Nutrition, RB2, retinoblastoma gene, TP53, World Health Organization on October 19, 2018| Leave a Comment »

Live 12:00 – 1:00 P.M Mediterranean Diet and Lifestyle: A Symposium on Diet and Human Health : October 19, 2018

Reporter: Stephen J. Williams, Ph.D.

12.00 The Italian Mediterranean Diet as a Model of Identity of a People with a Universal Good to Safeguard Health?

Prof. Antonino De Lorenzo, MD, PhD.

Director of the School of Specialization in Clinical Nutrition, University of Rome “Tor Vergata”

It is important to determine how our bodies interacts with the environment, such as absorption of nutrients.

Studies shown here show decrease in life expectancy of a high sugar diet, but the quality of the diet, not just the type of diet is important, especially the role of natural probiotics and phenolic compounds found in the Mediterranean diet.

The WHO report in 2005 discusses the unsustainability of nutrition deficiencies and suggest a proactive personalized and preventative/predictive approach of diet and health.

Most of the noncommunicable diseases like CV (46%) cancer 21% and 11% respiratory and 4% diabetes could be prevented and or cured with proper dietary approaches

Italy vs. the US diseases: in Italy most disease due to environmental contamination while US diet plays a major role

The issue we are facing in less than 10% of the Italian population (fruit, fibers, oils) are not getting the proper foods, diet and contributing to as we suggest 46% of the disease

The Food Paradox: 1.5 billion are obese; we notice we are eating less products of quality and most quality produce is going to waste;

growing BMI and junk food: our studies are correlating the junk food (pre-prepared) and global BMI
modern diet and impact of human health (junk food high in additives, salt) has impact on microflora
Western Diet and Addiction: We show a link (using brain scans) showing correlation of junk food, sugar cravings, and other addictive behaviors by affecting the dopamine signaling in the substantia nigra
developed a junk food calculator and a Mediterranean diet calculator
the intersection of culture, food is embedded in the Mediterranean diet; this is supported by dietary studies of two distinct rural Italian populations (one of these in the US) show decrease in diet
Impact of diet: have model in Germany how this diet can increase health and life expectancy
from 1950 to present day 2.7 unit increase in the diet index can increase life expectancy by 26%
so there is an inverse relationship with our index and breast cancer

Environment and metal contamination and glyphosate: contribution to disease and impact of maintaining the healthy diet

huge problem with use of pesticides and increase in celiac disease

12:30 Environment and Health

Dr. Iris Maria Forte, PhD.

National Cancer Institute “Pascale” Foundation | IRCCS · Department of Research, Naples, Italy

Cancer as a disease of the environment. Weinberg’s hallmarks of Cancer reveal how environment and epigenetics can impact any of these hallmarks.

Epigenetic effects

gene gatekeepers (Rb and P53)
DNA repair and damage stabilization

Heavy Metals and Dioxins:( alterations of the immune system as well as epigenetic regulations)

Asbestos and Mesothelioma: they have demonstrated that p53 can be involved in development of mesothelioma as reactivating p53 may be a suitable strategy for therapy

Diet, Tomato and Cancer

looked at tomato extract on p53 function in gastric cancer: tomato extract had a growth reduction effect and altered cell cycle regulation and results in apoptosis
RBL2 levels are increased in extract amount dependent manner so data shows effect of certain tomato extracts of the southern italian tomato ( )

Antonio Giordano: we tested whole extracts of almost 30 different varieties of tomato. The tomato variety with highest activity was near Ravela however black tomatoes have shown high antitumor activity. We have done a followup studies showing that these varieties, if grow elsewhere lose their antitumor activity after two or three generations of breeding, even though there genetics are similar. We are also studying the effects of different styles of cooking of these tomatoes and if it reduces antitumor effect

please see post https://news.temple.edu/news/2017-08-28/muse-cancer-fighting-tomatoes-study-italian-food

To follow or Tweet on Twitter please use the following handles (@) and hashtags (#):

@ handles

# hashtags

#health

#nutrition

Please see related articles on Live Coverage of Previous Meetings on this Open Access Journal

Real Time Conference Coverage for Scientific and Business Media: Unique Twitter Hashtags and Handles per Conference Presentation/Session

LIVE – Real Time – 16th Annual Cancer Research Symposium, Koch Institute, Friday, June 16, 9AM – 5PM, Kresge Auditorium, MIT

Real Time Coverage and eProceedings of Presentations on 11/16 – 11/17, 2016, The 12th Annual Personalized Medicine Conference, HARVARD MEDICAL SCHOOL, Joseph B. Martin Conference Center, 77 Avenue Louis Pasteur, Boston

Tweets Impression Analytics, Re-Tweets, Tweets and Likes by @AVIVA1950 and @pharma_BI for 2018 BioIT, Boston, 5/15 – 5/17, 2018

BIO 2018! June 4-7, 2018 at Boston Convention & Exhibition Center

LIVE 2018 The 21st Gabay Award to LORENZ STUDER, Memorial Sloan Kettering Cancer Center, contributions in stem cell biology and patient-specific, cell-based therapy

HUBweek 2018, October 8-14, 2018, Greater Boston – “We The Future” – coming together, of breaking down barriers, of convening across disciplinary lines to shape our future

Read Full Post »

Cancer threat in CRISPR/Cas9 method

Posted in Apoptosis, Apoptosis, Cancer - General, Cancer and Current Therapeutics, CANCER BIOLOGY & Innovations in Cancer Therapy, Cancer Genomics, Cancer Prevention: Research & Programs, Cancer Screening, Cancer-Immune Interactions, Cell Biology, Cell death pathways, Cell Processing System in Cell Therapy Process Development, Clinical Genomics, DNA repair, Efficacy of Anti-Tumor T Cells, Gene Regulation, Gene Therapy & Gene Editing Development, Genetics & Innovations in Treatment, Human Antibody Response, Transformative Technologies in Healthcare, Translational Research, tagged Cancer, CRISPR-Cas9, Double Strand Break, p53, T cells on June 17, 2018| Leave a Comment »

Reporter and Curator: Dr. Sudipta Saha, Ph.D.

The CRISPR-Cas9 system has proven to be a powerful tool for genome editing allowing for the precise modification of specific DNA sequences within a cell. Many efforts are currently underway to use the CRISPR-Cas9 system for the therapeutic correction of human genetic diseases. CRISPR/Cas9 has revolutionized our ability to engineer genomes and conduct genome-wide screens in human cells.

CRISPR–Cas9 induces a p53-mediated DNA damage response and cell cycle arrest in immortalized human retinal pigment epithelial cells, leading to a selection against cells with a functional p53 pathway. Inhibition of p53 prevents the damage response and increases the rate of homologous recombination from a donor template. These results suggest that p53 inhibition may improve the efficiency of genome editing of untransformed cells and that p53 function should be monitored when developing cell-based therapies utilizing CRISPR–Cas9.

Whereas some cell types are amenable to genome engineering, genomes of human pluripotent stem cells (hPSCs) have been difficult to engineer, with reduced efficiencies relative to tumour cell lines or mouse embryonic stem cells. Using hPSC lines with stable integration of Cas9 or transient delivery of Cas9-ribonucleoproteins (RNPs), an average insertion or deletion (indel) efficiency greater than 80% was achieved. This high efficiency of insertion or deletion generation revealed that double-strand breaks (DSBs) induced by Cas9 are toxic and kill most hPSCs.

The toxic response to DSBs was P53/TP53-dependent, such that the efficiency of precise genome engineering in hPSCs with a wild-type P53 gene was severely reduced. These results indicate that Cas9 toxicity creates an obstacle to the high-throughput use of CRISPR/Cas9 for genome engineering and screening in hPSCs. As hPSCs can acquire P53 mutations, cell replacement therapies using CRISPR/Cas9-enginereed hPSCs should proceed with caution, and such engineered hPSCs should be monitored for P53 function.

CRISPR-based editing of T cells to treat cancer, as scientists at the University of Pennsylvania are studying in a clinical trial, should also not have a p53 problem. Nor should any therapy developed with CRISPR base editing, which does not make the double-stranded breaks that trigger p53. But, there are pre-existing humoral and cell-mediated adaptive immune responses to Cas9 in humans, a factor which must be taken into account as the CRISPR-Cas9 system moves forward into clinical trials.

References:

https://techonomy.com/2018/06/new-cancer-concerns-shake-crispr-prognosis/

https://www.statnews.com/2018/06/11/crispr-hurdle-edited-cells-might-cause-cancer/

https://www.biorxiv.org/content/early/2017/07/26/168443

https://www.nature.com/articles/s41591-018-0049-z.epdf?referrer_access_token=s92jDP_yPBmDmi-USafzK9RgN0jAjWel9jnR3ZoTv0MRjuB3dEnTctGtoy16n3DDbmISsvbln9SCISHVDd73tdQRNS7LB8qBlX1vpbLE0nK_CwKThDGcf344KR6RAm9k3wZiwyu-Kb1f2Dl7pArs5yYSiSLSdgeH7gst7lOBEh9qIc6kDpsytWLHqX_tyggu&tracking_referrer=www.statnews.com

https://www.nature.com/articles/s41591-018-0050-6.epdf?referrer_access_token=2KJ0L-tmvjtQdzqlkVXWVNRgN0jAjWel9jnR3ZoTv0Phq6GCpDlJx7lIwhCzBRjHJv0mv4zO0wzJJCeuxJjzoUWLeemH8T4I3i61ftUBkYkETi6qnweELRYMj4v0kLk7naHF-ujuz4WUf75mXsIRJ3HH0kQGq1TNYg7tk3kamoelcgGp4M7UTiTmG8j0oog_&tracking_referrer=www.statnews.com

https://www.biorxiv.org/content/early/2018/01/05/243345

https://www.nature.com/articles/nmeth.4293.epdf

Read Full Post »

Lesson 9 Cell Signaling: Curations and Articles of reference as supplemental information for lecture section on WNTs: #TUBioll3373

Posted in Anticancer Resistance, Apoptosis, Biochemical pathways, Biological Networks, Biological Networks, Gene Regulation and Evolution, Breast Cancer - impalpable breast lesions, Ca2+ triggered activation, Calcium, Calcium Signaling, Calmodulin, Calmodulin Kinase and Contraction, Cancer - General, Cancer and Current Therapeutics, CANCER BIOLOGY & Innovations in Cancer Therapy, Cancer Genomics, Cell Biology, Cell Biology, Signaling & Cell Circuits, Competition in regenerative stem cell science, Curation, Loss of function gene, Phosphorylation, Scientific Publishing, Signaling, Ubiquitinylation, Uncategorized, tagged #TUBiol3373, actin, APC, breast cancer, Cancer, Cell Motility, colon cancer, epithelial ovarian cancer, Extracellular matrix, Hepatocellular carcinoma, HNPCC, noncanonical, tumor associated fibroblasts, Ubiquitin, Wnt signaling, Wnt signaling pathway, wnt-beta/catenin signaling on May 1, 2018| Leave a Comment »

Lesson 9 Cell Signaling: Curations and Articles of reference as supplemental information for lecture section on WNTs: #TUBiol3373

Stephen J. Wiilliams, Ph.D: Curator

UPDATED 4/23/2019

This has an updated lesson on WNT signaling. Please click on the following and look at the slides labeled under lesson 10

cell motility 9b lesson_2018_sjw

Remember our lessons on the importance of signal termination. The CANONICAL WNT signaling (that is the β-catenin dependent signaling)

is terminated by the APC-driven degradation complex. This leads to the signal messenger β-catenin being degraded by the proteosome. Other examples of growth factor signaling that is terminated by a proteosome-directed include the Hedgehog signaling system, which is involved in growth and differentiation as well as WNTs and is implicated in various cancers.

A good article on the Hedgehog signaling pathway is found here:

The Voice of a Pathologist, Cancer Expert: Scientific Interpretation of Images: Cancer Signaling Pathways and Tumor Progression

All images in use for this article are under copyrights with Shutterstock.com

Cancer is expressed through a series of transformations equally involving metabolic enzymes and glucose, fat, and protein metabolism, and gene transcription, as a result of altered gene regulatory and transcription pathways, and also as a result of changes in cell-cell interactions. These are embodied in the following series of graphics.

Figure 1: Sonic_hedgehog_pathway

The Voice of Dr. Larry

The figure shows a modification of nuclear translocation by Sonic hedgehog pathway. The hedgehog proteins have since been implicated in the development of internal organs, midline neurological structures, and the hematopoietic system in humans. The Hh signaling pathway consists of three main components: the receptor patched 1 (PTCH1), the seven transmembrane G-protein coupled receptor smoothened (SMO), and the intracellular glioma-associated oncogene homolog (GLI) family of transcription factors.⁵The GLI family is composed of three members, including GLI1 (gene activating), GLI2 (gene activating and repressive), and GLI3 (gene repressive).⁶ In the absence of an activating signal from either Shh, Ihh or Dhh, PTCH1 exerts an inhibitory effect on the signal transducer SMO, preventing any downstream signaling from occurring.⁷ When Hh ligands bind and activate PTCH1, the inhibition on SMO is released, allowing the translocation of SMO into the cytoplasm and its subsequent activation of the GLI family of transcription factors.

And from the review of Elaine Y. C. Hsia, Yirui Gui, and Xiaoyan Zheng Regulation of Hedgehog Signaling by Ubiquitination Front Biol (Beijing). 2015 Jun; 10(3): 203–220.

the authors state:

Finally, termination of Hh signaling is also important for controlling the duration of pathway activity. Hh induced ubiquitination and degradation of Ci/Gli is the most well-established mechanism for limiting signal duration, and inhibiting this process can lead to cell patterning disruption and excessive cell proliferation (Di Marcotullio et al. 2006; Huntzicker et al. 2006; Kent et al. 2006; Zhang et al. 2006a; Di Marcotullio et al. 2007; Ou et al. 2007). In addition to Ci/Gli, a growing body of evidence suggests that ubiquitination also plays critical roles in regulating other Hh signaling components including Ptc, Smo, and Sufu. Thus, ubiquitination serves as a general mechanism in the dynamic regulation of the Hh pathway.

Overview of Hedgehog signaling showing the signal termination by ubiquitnation and subsequent degradation of the Gli transcriptional factors. obtained from Oncotarget 5(10):2881-911 · May 2014. GSK-3B as a Therapeutic Intervention in Cancer

Note that in absence of Hedgehog ligands Ptch inhibits Smo accumulation and activation but upon binding of Hedgehog ligands (by an autocrine or paracrine fashion) Ptch is now unable to inhibit Smo (evidence exists that Ptch is now targeted for degradation) and Smo can now inhibit Sufu-dependent and GSK-3B dependent induced degradation of Gli factors Gli1 and Gli2. Also note the Gli1 and Gli2 are transcriptional activators while Gli3 is a transcriptional repressor.

UPDATED 4/16/2019

Please click on the following links for the Powerpoint presentation for lesson 9. In addition click on the mp4 links to download the movies so you can view them in Powerpoint slide 22:

cell motility 9 lesson_SJW 2019

movie file 1:

Tumorigenic but noninvasive MCF-7 cells motility on an extracellular matrix derived from normal (3DCntrol) or tumor associated (TA) fibroblasts. Note that TA ECM is “soft” and not organized and tumor cells appear to move randomly if much at all.

Movie 2:

Note that these tumorigenic and invasive MDA-MB-231 breast cancer cells move in organized patterns on organized ECM derived from Tumor Associated (TA) fibroblasts than from the ‘soft’ or unorganized ECM derived from normal (3DCntrl) fibroblasts

The following contain curations of scientific articles from the site https://pharmaceuticalintelligence.com intended as additional reference material to supplement material presented in the lecture.

Wnts are a family of lipid-modified secreted glycoproteins which are involved in:

Normal physiological processes including

A. Development:

– Osteogenesis and adipogenesis (Loss of wnt/β‐catenin signaling causes cell fate shift of preosteoblasts from osteoblasts to adipocytes)

– embryogenesis including body axis patterning, cell fate specification, cell proliferation and cell migration

B. tissue regeneration in adult tissue

read: Wnt signaling in the intestinal epithelium: from endoderm to cancer

And in pathologic processes such as oncogenesis (refer to Wnt/β-catenin Signaling [7.10]) and to your Powerpoint presentation

The curation Wnt/β-catenin Signaling is a comprehensive review of canonical and noncanonical Wnt signaling pathways

To review:

Activating the canonical Wnt pathway frees B-catenin from the degradation complex, resulting in B-catenin translocating to the nucleus and resultant transcription of B-catenin/TCF/LEF target genes.

Fig. 1 Canonical Wnt/FZD signaling pathway. (A) In the absence of Wnt signaling, soluble β-catenin is phosphorylated by a degradation complex consisting of the kinases GSK3β and CK1α and the scaffolding proteins APC and Axin1. Phosphorylated β-catenin is targeted for proteasomal degradation after ubiquitination by the SCF protein complex. In the nucleus and in the absence of β-catenin, TCF/LEF transcription factor activity is repressed by TLE-1; (B) activation of the canonical Wnt/FZD signaling leads to phosphorylation of Dvl/Dsh, which in turn recruits Axin1 and GSK3β adjacent to the plasma membrane, thus preventing the formation of the degradation complex. As a result, β-catenin accumulates in the cytoplasm and translocates into the nucleus, where it promotes the expression of target genes via interaction with TCF/LEF transcription factors and other proteins such as CBP, Bcl9, and Pygo.

NOTE: In the canonical signaling, the Wnt signal is transmitted via the Frizzled/LRP5/6 activated receptor to INACTIVATE the degradation complex thus allowing free B-catenin to act as the ultimate transducer of the signal.

Remember, as we discussed, the most frequent cancer-related mutations of WNT pathway constituents is in APC.

This shows how important the degradation complex is in controlling canonical WNT signaling.

Other cell signaling systems are controlled by protein degradation:

A. The Forkhead family of transcription factors

Read: Regulation of FoxO protein stability via ubiquitination and proteasome degradation

B. Tumor necrosis factor α/NF κB signaling

Read: NF-κB, the first quarter-century: remarkable progress and outstanding questions

1. Question: In cell involving G-proteins, the signal can be terminated by desensitization mechanisms. How is both the canonical and noncanonical Wnt signal eventually terminated/desensitized?

We also discussed the noncanonical Wnt signaling pathway (independent of B-catenin induced transcriptional activity). Note that the canonical and noncanonical involve different transducers of the signal.

Noncanonical WNT Signaling

Note: In noncanonical signaling the transducer is a G-protein and second messenger system is IP₃/DAG/Ca++ and/or kinases such as MAPK, JNK.

Depending on the different combinations of WNT ligands and the receptors, WNT signaling activates several different intracellular pathways (i.e. canonical versus noncanonical)

In addition different Wnt ligands are expressed at different times (temporally) and different cell types in development and in the process of oncogenesis.

The following paper on Wnt signaling in ovarian oncogenesis shows how certain Wnt ligands are expressed in normal epithelial cells but the Wnt expression pattern changes upon transformation and ovarian oncogenesis. In addition, differential expression of canonical versus noncanonical WNT ligands occur during the process of oncogenesis (for example below the authors describe the noncanonical WNT5a is expressed in normal ovarian epithelia yet WNT5a expression in ovarian cancer is lower than the underlying normal epithelium. However the canonical WNT10a, overexpressed in ovarian cancer cells, serves as an oncogene, promoting oncogenesis and tumor growth.

Wnt5a Suppresses Epithelial Ovarian Cancer by Promoting Cellular Senescence

Benjamin G. Bitler,¹ Jasmine P. Nicodemus,¹ Hua Li,¹ Qi Cai,² Hong Wu,³ Xiang Hua,⁴ Tianyu Li,⁵ Michael J. Birrer,⁶Andrew K. Godwin,⁷ Paul Cairns,⁸ and Rugang Zhang^1,*

A. Abstract

Epithelial ovarian cancer (EOC) remains the most lethal gynecological malignancy in the US. Thus, there is an urgent need to develop novel therapeutics for this disease. Cellular senescence is an important tumor suppression mechanism that has recently been suggested as a novel mechanism to target for developing cancer therapeutics. Wnt5a is a non-canonical Wnt ligand that plays a context-dependent role in human cancers. Here, we investigate the role of Wnt5a in regulating senescence of EOC cells. We demonstrate that Wnt5a is expressed at significantly lower levels in human EOC cell lines and in primary human EOCs (n = 130) compared with either normal ovarian surface epithelium (n = 31; p = 0.039) or fallopian tube epithelium (n = 28; p < 0.001). Notably, a lower level of Wnt5a expression correlates with tumor stage (p = 0.003) and predicts shorter overall survival in EOC patients (p = 0.003). Significantly, restoration of Wnt5a expression inhibits the proliferation of human EOC cells both in vitro and in vivo in an orthotopic EOC mouse model. Mechanistically, Wnt5a antagonizes canonical Wnt/β-catenin signaling and induces cellular senescence by activating the histone repressor A (HIRA)/promyelocytic leukemia (PML) senescence pathway. In summary, we show that loss of Wnt5a predicts poor outcome in EOC patients and Wnt5a suppresses the growth of EOC cells by triggering cellular senescence. We suggest that strategies to drive senescence in EOC cells by reconstituting Wnt5a signaling may offer an effective new strategy for EOC therapy.

Oncol Lett. 2017 Dec;14(6):6611-6617. doi: 10.3892/ol.2017.7062. Epub 2017 Sep 26.

Clinical significance and biological role of Wnt10a in ovarian cancer.

Li P¹, Liu W¹, Xu Q¹, Wang C¹.

Ovarian cancer is one of the five most malignant types of cancer in females, and the only currently effective therapy is surgical resection combined with chemotherapy. Wnt family member 10A (Wnt10a) has previously been identified to serve an oncogenic function in several tumor types, and was revealed to have clinical significance in renal cell carcinoma; however, there is still only limited information regarding the function of Wnt10a in the carcinogenesis of ovarian cancer. The present study identified increased expression levels of Wnt10a in two cell lines, SKOV3 and A2780, using reverse transcription-polymerase chain reaction. Functional analysis indicated that the viability rate and migratory ability of SKOV3 cells was significantly inhibited following Wnt10a knockdown using short interfering RNA (siRNA) technology. The viability rate of SKOV3 cells decreased by ~60% compared with the control and the migratory ability was only ~30% of that in the control. Furthermore, the expression levels of β-catenin, transcription factor 4, lymphoid enhancer binding factor 1 and cyclin D1 were significantly downregulated in SKOV3 cells treated with Wnt10a-siRNA3 or LGK-974, a specific inhibitor of the canonical Wnt signaling pathway. However, there were no synergistic effects observed between Wnt10a siRNA3 and LGK-974, which indicated that Wnt10a activated the Wnt/β-catenin signaling pathway in SKOV3 cells. In addition, using quantitative PCR, Wnt10a was overexpressed in the tumor tissue samples obtained from 86 patients with ovarian cancer when compared with matching paratumoral tissues. Clinicopathological association analysis revealed that Wnt10a was significantly associated with high-grade (grade III, P=0.031) and late-stage (T4, P=0.008) ovarian cancer. Furthermore, the estimated 5-year survival rate was 18.4% for patients with low Wnt10a expression levels (n=38), whereas for patients with high Wnt10a expression (n=48) the rate was 6.3%. The results of the present study suggested that Wnt10a serves an oncogenic role during the carcinogenesis and progression of ovarian cancer via the Wnt/β-catenin signaling pathway.

Targeting the Wnt Pathway includes curations of articles related to the clinical development of Wnt signaling inhibitors as a therapeutic target in various cancers including hepatocellular carcinoma, colon, breast and potentially ovarian cancer.