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Posts Tagged ‘hematological cancers’


Development of Chemoresistance to Targeted Therapies: Alterations of Cell Signaling, & the Kinome [11.4.1.2]

 

Curator, Reporter: Stephen J. Williams, Ph.D.

The advent of molecular targeted therapies like Imatinib (Gleevec), and other tyrosine kinase inhibitors (TKI) has been transformative to cancer therapy. However, as with all chemotherapeutics, including radiation therapy, the development of chemo-resistance toward personalized, molecular therapies has been disastrous to the successful treatment of cancer. The fact that chemo-resistance develops to personalized therapies was a serious disappointment to clinicians (although most expected this to be the case) but more surprisingly it was the rapidity of onset and speed of early reported cases which may have been the biggest shocker.

A post on resistance to other TKIs (to EGFR and ALK) can be seen here: https://pharmaceuticalintelligence.com/2013/11/01/resistance-to-receptor-of-tyrosine-kinase/

History of Development of Resistance to Imatinib (Gleevec)

The Melo group published a paper in Blood showing that short exposure to STI571 (imatinib; trade name Gleevec®) could result in drug resistant clones

Selection and characterization of BCR-ABL positive cell lines with differential sensitivity to the tyrosine kinase inhibitor STI571: diverse mechanisms of resistance. Blood. 2000 Aug 1;96(3):1070-9.

Mahon FX1, Deininger MW, Schultheis B, Chabrol J, Reiffers J, Goldman JM, Melo JV.

Abstract

Targeting the tyrosine kinase activity of Bcr-Abl with STI571 is an attractive therapeutic strategy in chronic myelogenous leukemia (CML). A few CML cell lines and primary progenitors are, however, resistant to this compound. We investigated the mechanism of this resistance in clones of the murine BaF/3 cells transfected with BCR-ABL and in 4 human cell lines from which sensitive (s) and resistant (r) clones were generated by various methods. Although the resistant cells were able to survive in the presence of STI571, their proliferation was approximately 30% lower than that of their sensitive counterparts in the absence of the compound. The concentration of STI571 needed for a 50% reduction in viable cells after a 3-day exposure was on average 10 times higher in the resistant (2-3 micromol/L) than in the sensitive (0.2-0.25 micromol/L) clones. The mechanism of resistance to STI571 varied among the cell lines. Thus, in Baf/BCR-ABL-r, LAMA84-r, and AR230-r, there was up-regulation of the Bcr-Abl protein associated with amplification of the BCR-ABL gene. In K562-r, there was no Bcr-Abl overexpression, but the IC(50) for the inhibition of Bcr-Abl autophosphorylation was increased in the resistant clones. Sequencing of the Abl kinase domain revealed no mutations. The multidrug resistance P-glycoprotein (Pgp) was overexpressed in LAMA84-r, indicating that at least 2 mechanisms of resistance operate in this cell line. KCL22-r showed neither Bcr-Abl up-regulation nor a higher threshold for tyrosine kinase inhibition by STI571. We conclude that BCR-ABL-positive cells can evade the inhibitory effect of STI571 by different mechanisms, such as Bcr-Abl overexpression, reduced intake mediated by Pgp, and, possibly, acquisition of compensatory mutations in genes other than BCR-ABL.

mellobcrablresistamplification

FISH analysis of AR230 and LAMA84 sensitive and resistant clones, with probes for the ABL (red signal) and theBCR (green signal) genes. BCR-ABL is identified as a red–green or yellow fused signal. Adapted from Mahon et al., Blood 2000; 96(3):1070-9.

This rapid onset of imatinib resistance also see in the clinic and more prominent in advance disease

From NCCN 2nd Annual Congress: Hematologic Malignancies – Update on Primary Therapy, Second-Line Therapy, and New Agents for Chronic Myelogenous Leukemia (Slides with Transcript)

http://www.medscape.org/viewarticle/564097

There is some evidence that even looking earlier makes some sense in determining what the prognosis is. This is from Timothy Hughes’ group in Adelaide, and he is looking at an earlier molecular time point, 3 months after initiation of therapy. And what you have done here is you have taken the 3-month mark and you have said, “Well, based on your response at 3 months, what is your likelihood that in the future you will either get a major molecular response or become resistant?”

3monthimitanibresist

If you look at the accumulation of imatinib resistance to find if it is either initially not responding or becoming resistant after a good response, it goes up with type of disease and phase of disease. So if you look at patients who have early chronic phase disease — that is, they start getting imatinib less than a year from the diagnosis — their chance of failure is pretty low. With later disease — they are in a chronic phase but they have had disease more than a year before they get imatinib — it is higher. If you see patients with accelerated phase or blast crisis, the chances are that they will fail sometime in the future.

speed of imitinib resistance

Therefore, because not all resistant samples show gene amplification of Bcr/Abl and the rapidity of onset of resistance, many feel that there are other mechanisms of resistance at play, like kinome plasticity.

Kinome Plasticity Contributes to TKI resistance

Beyond gene amplification, other mechanisms of imitanib and other tyrosine kinase inhibitors (TKI) include alterations in compensatory signaling pathways. This can be referred to as kinome plasticity and is explained in the following abstracts from the AACR 2015 meeting.

Systems-pharmacology dissection of a drug synergy in imatinib-resistant CML

Georg E Winter, Uwe Rix, Scott M Carlson, Karoline V Gleixner, Florian Grebien, Manuela Gridling, André C Müller, Florian P Breitwieser, Martin Bilban, Jacques Colinge, Peter Valent, Keiryn L Bennett, Forest M White & Giulio Superti-Furga. Nature Chemical Biology 8,905–912(2012)

Occurrence of the BCR-ABLT315I gatekeeper mutation is among the most pressing challenges in the therapy of chronic myeloid leukemia (CML). Several BCR-ABL inhibitors have multiple targets and pleiotropic effects that could be exploited for their synergistic potential. Testing combinations of such kinase inhibitors identified a strong synergy between danusertib and bosutinib that exclusively affected CML cells harboring BCR-ABLT315I. To elucidate the underlying mechanisms, we applied a systems-level approach comprising phosphoproteomics, transcriptomics and chemical proteomics. Data integration revealed that both compounds targeted Mapk pathways downstream of BCR-ABL, resulting in impaired activity of c-Myc. Using pharmacological validation, we assessed that the relative contributions of danusertib and bosutinib could be mimicked individually by Mapk inhibitors and collectively by downregulation of c-Myc through Brd4 inhibition. Thus, integration of genome- and proteome-wide technologies enabled the elucidation of the mechanism by which a new drug synergy targets the dependency of BCR-ABLT315I CML cells on c-Myc through nonobvious off targets.

nchembio.1085-F2kinomegleevecresistance

Please see VIDEO and SLIDESHARE of a roundtable Expert Discussion on CML

Curated Content From the 2015 AACR National Meeting on Drug Resistance Mechanisms and tyrosine kinase inhibitors

Session Title: Mechanisms of Resistance: From Signaling Pathways to Stem Cells
Session Type: Major Symposium
Session Start/End Time: Tuesday, Apr 21, 2015, 10:30 AM -12:30 PM
Location: Terrace Ballroom II-III (400 Level), Pennsylvania Convention Center
CME: CME-Designated
CME/CE Hours: 2
Session Description: Even the most effective cancer therapies are limited due to the development of one or more resistance mechanisms. Acquired resistance to targeted therapies can, in some cases, be attributed to the selective propagation of a small population of intrinsically resistant cells. However, there is also evidence that cancer drugs themselves can drive resistance by triggering the biochemical- or genetic-reprogramming of cells within the tumor or its microenvironment. Therefore, understanding drug resistance at the molecular and biological levels may enable the selection of specific drug combinations to counteract these adaptive responses. This symposium will explore some of the recent advances addressing the molecular basis of cancer cell drug resistance. We will address how tumor cell signaling pathways become rewired to facilitate tumor cell survival in the face of some of our most promising cancer drugs. Another topic to be discussed involves how drugs select for or induce the reprogramming of tumor cells toward a stem-like, drug resistant fate. By targeting the molecular driver(s) of rewired signaling pathways and/or cancer stemness it may be possible to select drug combinations that prevent the reprogramming of tumors and thereby delay or eliminate the onset of drug resistance.
Presentations:
Chairperson
Tuesday, Apr 21, 2015, 10:30 AM -12:30 PM
David A. Cheresh. UCSD Moores Cancer Center, La Jolla, CA
Introduction
Tuesday, Apr 21, 2015, 10:30 AM -10:40 AM
Resistance to tyrosine kinase inhibitors: Heterogeneity and therapeutic strategies.
Tuesday, Apr 21, 2015, 10:40 AM -10:55 AM
Jeffrey A. Engelman. Massachusetts General Hospital, Boston, MA
Discussion
Tuesday, Apr 21, 2015, 10:55 AM -11:00 AM
NG04: Clinical acquired resistance to RAF inhibitor combinations in BRAF mutant colorectal cancer through MAPK pathway alterations
Tuesday, Apr 21, 2015, 11:00 AM -11:15 AM
Ryan B. Corcoran, Leanne G. Ahronian, Eliezer Van Allen, Erin M. Coffee, Nikhil Wagle, Eunice L. Kwak, Jason E. Faris, A. John Iafrate, Levi A. Garraway, Jeffrey A. Engelman. Massachusetts General Hospital Cancer Center, Boston, MA, Dana-Farber Cancer Institute, Boston, MA
Discussion
Tuesday, Apr 21, 2015, 11:15 AM -11:20 AM
SY27-02: Tumour heterogeneity and therapy resistance in melanoma
Tuesday, Apr 21, 2015, 11:20 AM -11:35 AM
Claudia Wellbrock. Univ. of Manchester, Manchester, United Kingdom
Discussion
Tuesday, Apr 21, 2015, 11:35 AM -11:40 AM
SY27-03: Breast cancer stem cell state transitions mediate therapeutic resistance
Tuesday, Apr 21, 2015, 11:40 AM -11:55 AM
Max S. Wicha. University of Michigan, Comprehensive Cancer Center, Ann Arbor, MI
Discussion
Tuesday, Apr 21, 2015, 11:55 AM -12:00 PM
SY27-04: Induction of cancer stemness and drug resistance by EGFR blockade
Tuesday, Apr 21, 2015, 12:00 PM -12:15 PM
David A. Cheresh. UCSD Moores Cancer Center, La Jolla, CA
Discussion
Tuesday, Apr 21, 2015, 12:15 PM -12:20 PM
General Discussion
Tuesday, Apr 21, 2015, 12:20 PM -12:30 PM

Targeting Macromolecular Signaling Complexes 
Room 115, Pennsylvania Convention Center

Drug Resistance 
Hall A (200 Level), Pennsylvania Convention Center
Resistance to Pathway-Targeted Therapeutics 1 
Section 33

Molecular Mechanisms of Sensitivity or Resistance to Pathway-Targeted Agents 
Room 118, Pennsylvania Convention Center

Targeting Signaling Pathways in Cancer 
Room 204, Pennsylvania Convention Center
Exploiting the MAPK Pathway in Cancer 
Room 115, Pennsylvania Convention Center

PLEASE see the attached WORD file which includes ALL abstracts, posters, and talks on this subject from the AACR 2015 national meeting BELOW

 AACR2015resistancekinome

Other posts related to, Cancer, Chemotherapy, Gleevec and Resistance on this Open Access Journal Include

Imatinib (Gleevec) May Help Treat Aggressive Lymphoma: Chronic Lymphocytic Leukemia (CLL)

Treatments for Acute Leukemias [2.4.4A]

Therapeutic Implications for Targeted Therapy from the Resurgence of Warburg ‘Hypothesis’

Hematologic Malignancies [6.2]

Overview of Posttranslational Modification (PTM)

Novel Modeling Methods for Genomic Data Analysis & Evolutionary Systems Biology to Design Dosing Regimens to Minimize Resistance

Mechanisms of Drug Resistance

Using RNA-seq and targeted nucleases to identify mechanisms of drug resistance in acute myeloid leukemia

An alternative approach to overcoming the apoptotic resistance of pancreatic cancer

Resistance to Receptor of Tyrosine Kinase

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Treatment of Lymphomas [2.4.4C]

Larry H. Bernstein, MD, FCAP, Author, Curator, Editor

http://pharmaceuticalinnovation.com/2015/8/11/larryhbern/Treatment-of-Lymphomas-[2.4.4C]

 

Lymphoma treatment

Overview

http://www.emedicinehealth.com/lymphoma/page8_em.htm#lymphoma_treatment

The most widely used therapies are combinations of chemotherapyand radiation therapy.

  • Biological therapy, which targets key features of the lymphoma cells, is used in many cases nowadays.

The goal of medical therapy in lymphoma is complete remission. This means that all signs of the disease have disappeared after treatment. Remission is not the same as cure. In remission, one may still have lymphoma cells in the body, but they are undetectable and cause no symptoms.

  • When in remission, the lymphoma may come back. This is called recurrence.
  • The duration of remission depends on the type, stage, and grade of the lymphoma. A remission may last a few months, a few years, or may continue throughout one’s life.
  • Remission that lasts a long time is called durable remission, and this is the goal of therapy.
  • The duration of remission is a good indicator of the aggressiveness of the lymphoma and of the prognosis. A longer remission generally indicates a better prognosis.

Remission can also be partial. This means that the tumor shrinks after treatment to less than half its size before treatment.

The following terms are used to describe the lymphoma’s response to treatment:

  • Improvement: The lymphoma shrinks but is still greater than half its original size.
  • Stable disease: The lymphoma stays the same.
  • Progression: The lymphoma worsens during treatment.
  • Refractory disease: The lymphoma is resistant to treatment.

The following terms to refer to therapy:

  • Induction therapy is designed to induce a remission.
  • If this treatment does not induce a complete remission, new or different therapy will be initiated. This is usually referred to as salvage therapy.
  • Once in remission, one may be given yet another treatment to prevent recurrence. This is called maintenance therapy.

Chemotherapy

Many different types of chemotherapy may be used for Hodgkin lymphoma. The most commonly used combination of drugs in the United States is called ABVD. Another combination of drugs, known as BEACOPP, is now widely used in Europe and is being used more often in the United States. There are other combinations that are less commonly used and not listed here. The drugs that make up these two more common combinations of chemotherapy are listed below.

ABVD: Doxorubicin (Adriamycin), bleomycin (Blenoxane), vinblastine (Velban, Velsar), and dacarbazine (DTIC-Dome). ABVD chemotherapy is usually given every two weeks for two to eight months.

BEACOPP: Bleomycin, etoposide (Toposar, VePesid), doxorubicin, cyclophosphamide (Cytoxan, Neosar), vincristine (Vincasar PFS, Oncovin), procarbazine (Matulane), and prednisone (multiple brand names). There are several different treatment schedules, but different drugs are usually given every two weeks.

The type of chemotherapy, number of cycles of chemotherapy, and the additional use of radiation therapy are based on the stage of the Hodgkin lymphoma and the type and number of prognostic factors.

Adult Non-Hodgkin Lymphoma Treatment (PDQ®)

http://www.cancer.gov/cancertopics/pdq/treatment/adult-non-hodgkins/Patient/page1

Key Points for This Section

Adult non-Hodgkin lymphoma is a disease in which malignant (cancer) cells form in the lymph system.

Because lymph tissue is found throughout the body, adult non-Hodgkin lymphoma can begin in almost any part of the body. Cancer can spread to the liver and many other organs and tissues.

Non-Hodgkin lymphoma in pregnant women is the same as the disease in nonpregnant women of childbearing age. However, treatment is different for pregnant women. This summary includes information on the treatment of non-Hodgkin lymphoma during pregnancy

Non-Hodgkin lymphoma can occur in both adults and children. Treatment for children, however, is different than treatment for adults. (See the PDQ summary on Childhood Non-Hodgkin Lymphoma Treatment for more information.)

There are many different types of lymphoma.

Lymphomas are divided into two general types: Hodgkin lymphoma and non-Hodgkin lymphoma. This summary is about the treatment of adult non-Hodgkin lymphoma. For information about other types of lymphoma, see the following PDQ summaries:

Age, gender, and a weakened immune system can affect the risk of adult non-Hodgkin lymphoma.

If cancer is found, the following tests may be done to study the cancer cells:

  • Immunohistochemistry : A test that uses antibodies to check for certain antigens in a sample of tissue. The antibody is usually linked to a radioactive substance or a dye that causes the tissue to light up under a microscope. This type of test may be used to tell the difference between different types of cancer.
  • Cytogenetic analysis : A laboratory test in which cells in a sample of tissue are viewed under a microscope to look for certain changes in the chromosomes.
  • Immunophenotyping : A process used to identify cells, based on the types of antigens ormarkers on the surface of the cell. This process is used to diagnose specific types of leukemia and lymphoma by comparing the cancer cells to normal cells of the immune system.

Certain factors affect prognosis (chance of recovery) and treatment options.

The prognosis (chance of recovery) and treatment options depend on the following:

  • The stage of the cancer.
  • The type of non-Hodgkin lymphoma.
  • The amount of lactate dehydrogenase (LDH) in the blood.
  • The amount of beta-2-microglobulin in the blood (for Waldenström macroglobulinemia).
  • The patient’s age and general health.
  • Whether the lymphoma has just been diagnosed or has recurred (come back).

Stages of adult non-Hodgkin lymphoma may include E and S.

Adult non-Hodgkin lymphoma may be described as follows:

E: “E” stands for extranodal and means the cancer is found in an area or organ other than the lymph nodes or has spread to tissues beyond, but near, the major lymphatic areas.

S: “S” stands for spleen and means the cancer is found in the spleen.

Stage I adult non-Hodgkin lymphoma is divided into stage I and stage IE.

  • Stage I: Cancer is found in one lymphatic area (lymph node group, tonsils and nearby tissue, thymus, or spleen).
  • Stage IE: Cancer is found in one organ or area outside the lymph nodes.

Stage II adult non-Hodgkin lymphoma is divided into stage II and stage IIE.

  • Stage II: Cancer is found in two or more lymph node groups either above or below the diaphragm (the thin muscle below the lungs that helps breathing and separates the chest from the abdomen).
  • Stage IIE: Cancer is found in one or more lymph node groups either above or below the diaphragm. Cancer is also found outside the lymph nodes in one organ or area on the same side of the diaphragm as the affected lymph nodes.

Stage III adult non-Hodgkin lymphoma is divided into stage III, stage IIIE, stage IIIS, and stage IIIE+S.

  • Stage III: Cancer is found in lymph node groups above and below the diaphragm (the thin muscle below the lungs that helps breathing and separates the chest from the abdomen).
  • Stage IIIE: Cancer is found in lymph node groups above and below the diaphragm and outside the lymph nodes in a nearby organ or area.
  • Stage IIIS: Cancer is found in lymph node groups above and below the diaphragm, and in the spleen.
  • Stage IIIE+S: Cancer is found in lymph node groups above and below the diaphragm, outside the lymph nodes in a nearby organ or area, and in the spleen.

In stage IV adult non-Hodgkin lymphoma, the cancer:

  • is found throughout one or more organs that are not part of a lymphatic area (lymph node group, tonsils and nearby tissue, thymus, or spleen), and may be in lymph nodes near those organs; or
  • is found in one organ that is not part of a lymphatic area and has spread to organs or lymph nodes far away from that organ; or
  • is found in the liver, bone marrow, cerebrospinal fluid (CSF), or lungs (other than cancer that has spread to the lungs from nearby areas).

Adult non-Hodgkin lymphomas are also described based on how fast they grow and where the affected lymph nodes are in the body.  Indolent & aggressive.

The treatment plan depends mainly on the following:

  • The type of non-Hodgkin’s lymphoma
  • Its stage (where the lymphoma is found)
  • How quickly the cancer is growing
  • The patient’s age
  • Whether the patient has other health problems
  • If there are symptoms present such as fever and night sweats (see above)

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