Grant: 1351-18 | Career Development Program (CDP):
Location:The Ohio State University, Columbus, Ohio 43210
Project Title: Understanding And Overcoming Resistance To Bruton Tyrosine Kinase Inhibitors In Chronic Lymphocytic LeukemiaProject Summary:
Chronic lymphocytic leukemia (CLL) is the most common adult leukemia and until recently was treated with therapies toxic to the patient. Our clinical and research team at The Ohio State University Comprehensive Cancer Center helped provide critical information which led to the FDA approval of ibrutinib, a less toxic targeted therapy. Ibrutinib inhibits the BTK protein, which is a protein that CLL uses for its own pathological survival. Ibrutinib shows remarkable clinical activity that is more durable than any therapy ever studied in CLL. Unlike some CLL treatments, ibrutinib can be given to all age groups, making it a more widespread therapy. Ibrutinib’s success should form the basis for its inclusion in even more effective combination therapies that may someday lead to a cure. Historical experience indicates that effective new therapeutics for CLL will also have a major role in treatment of non-Hodgkin lymphoma and autoimmune diseases.
While ibrutinib is effective for many patients, some develop resistance to this treatment. My research team seeks to determine predictive genomic factors that result in BTK inhibitor therapy resistance. We discovered that some patients acquire mutations that then confer resistance to ibrutinib. The large group of patients treated with ibrutinib, including our collection of samples from patients with resistance mutations, represents an invaluable resource to pursue pre-clinical and clinical work to identify more effective CLL treatments. Exploring the mutations and their associated signaling pathways (which we will continue to discover) will help us understand ways to overcome treatment-related resistance by either early recognition or, potentially, novel therapeutic approaches.
Our experiments use primary CLL cells from patients whom are seen by our clinical team. We are also using the most appropriate laboratory-based model available for understanding preclinical drug development and CLL biology. Our experimental approach will directly address the Leukemia & Lymphoma Society’s mission to cure blood cancer by discovering new potentially curative treatment strategies for CLL.
Grant: 3374-18 | Career Development Program (CDP):
Location:Brigham and Women’s Hospital, Boston, Massachusetts 02241-3149
Project Title: Functional Characterization Of The Mutant Calreticulin-MPL Interaction In Myeloproliferative NeoplasmsProject Summary:
Myeloproliferative neoplasms (MPN) are a group of rare blood cancers that occur when the body produces too many white blood cells, red blood bloods, or platelets. Though the overall prognosis for MPN tends to be favorable, more advanced forms of these diseases can lead to severe anemia, increased risk of blood clots, and transformation to leukemia. MPN were first described in 1951 by hematologist William Dameshek, but the underlying genetic cause of these diseases remained a mystery for over 50 years. In 2005, four different research groups simultaneously discovered that approximately 63% of MPN patients harbor mutations in the gene JAK2. This was a tremendous breakthrough in the MPN field and led to the development of the FDA-approved drug ruxolitinib (Jakafi), a compound that inhibits JAK2 activity, for the treatment of MPN. Despite this advance however, the causal genetic abnormalities in the remaining 40% of non-mutated JAK2 MPN patients remained unknown for nearly a decade thereafter. In 2013, two different groups performed sequencing experiments on blood cells from non-mutated JAK2 MPN patients, and found that the majority of these patients harbor mutations in the gene calreticulin (CALR). The CALR gene encodes a “housekeeping” protein that resides in the endoplasmic reticulum (ER) and ensures quality control of protein folding in the cell. We currently have an incomplete understanding of the mechanism by which CALR mutations transform normal blood cells to cause MPN.
Unlike normal CALR, mutant CALR is found near the cell surface. Our recent research has shown that the mutations enable an interaction with a cell surface receptor protein called MPL. We have further shown that this interaction leads to an activation of the JAK2 pathway. A central hypothesis from this research is that mutant CALR binds to proteins that it does not normally bind to, and some of these proteins may be essential for the oncogenic activity of CALR. Building on this work, we will utilize state-of-the-art technology to determine the proteins mutant CALR binds to in the cell that are not bound by normal, non-mutated CALR. Through this work, we hope to gain a comprehensive understanding of the protein partners with which mutant CALR interacts in the cell to drive disease development, which would ultimately inform new targets for therapeutic intervention. Ultimately, we hope that our work will lead to improved therapeutic strategies for MPN patients, particularly those who do not respond well to ruxolitinib and other existing treatments.
Grant: 5461-18 | Career Development Program (CDP):
Location:The Trustees of Columbia University in the City of New York, Columbia University Medical Center, New York, New York 10027
Project Title: The Role Of NOTCH1 Controlled Micropeptides In T-ALLProject Summary:
Acute lymphoblastic leukemia (ALL) is the most common form of pediatric cancer and a leading cause of disease-driven death in children. Understanding the causes and mechanisms of leukemia is essential in order to develop specific highly active and less toxic treatments. One of the most common drivers of leukemia growth and survival is the NOTCH1 gene. NOTCH1 is frequently mutated in leukemia, and these mutations cause increased NOTCH1 activity, which in turn triggers a cellular program driving uncontrolled cell proliferation. Our understanding of the specifics of how NOTCH1 promotes leukemia transformation remains rudimentary.
Though most of our knowledge of T-ALL comes from the genetic dissection of known protein-coding genes, it is likely that other components of the genome contribute to T-ALL as well. A recently discovered component of the genome gives rise to very small proteins, called micropeptides that likely have profound effects on gene expression. Our research aims to investigate the role of this new family of gene-encoding proteins as potential key drivers of leukemia growth. Our central hypothesis is that among the multiple proteins controlled by NOTCH1, micropeptides are of particular importance for leukemia growth and survival. While large proteins function as molecular machines, micropeptides function as keys or switches that bind to and turn these molecular machines “on” and “off”. We are using the latest genomic technologies and refined computational approaches to identify the complete repertoire of NOTCH1-controlled micropeptides operating in leukemia. We will then evaluate the specific role and mechanisms by which these short proteins contribute to leukemia cell growth. Dissecting the mechanism of action of these key leukemia-driving micropeptides may identify novel targets for the treatment of ALL.
Grant: 6527-18 | Translational Research Program (TRP):
Location:Dana-Farber Cancer Institute, Boston, Massachusetts 02215
Project Title: Assessment Of Epigenetic Reprogramming Of The T Cell Response To CTLA-4 Blockade In AMLProject Summary:
The prognosis for patients with relapsed or refractory acute myeloid leukemia (AML)/myelodysplastic syndrome (MDS) whose disease comes back is poor, and innovative new therapeutic approaches are urgently needed. We conducted and published results from a clinical trial for patients whose blood cancer came back after bone marrow transplantation with ipilimumab, which is an antibody drug that uses the immune system to kill cancer cells. A small number of patients, including those with relapsed AML, had durable clinical responses. This clinical activity prompted us to develop a new proposal to evaluate whether or not we could safely boost response by adding a hypomethylating agent, decitabine, to ipilimumab treatment. Decitabine is a drug commonly used in the treatment of MDS/AML that is well-tolerated with modest clinical activity. Decitabine has the ability to affect the expression of genes. We now have a new approved clinical trial to assess the safety and clinical activity of the novel combination of decitabine plus ipilimumab in patients with relapsed or refractory AML/MDS who are post-transplant and who are transplant naïve. Using peripheral blood and bone marrow samples collected throughout treatment on study, we will evaluate the hypothesis that decitabine treatment might sensitize leukemia cells to ipilimumab by altering the immune response within the sites of leukemia infiltrates. Together with local expert collaborators we will perform a comprehensive analysis using patient samples collected from the clinical trial to evaluate for transcriptional (gene expression) and epigenetic (changes in a chromosome that alters gene activity and expression) changes within the immune cells present at leukemia sites including bone marrow and other tissues. We will then study which immune cells subpopulations are present and whether or not they have functional activity. We will correlate these laboratory findings with clinical activity to decitabine and ipilimumab to help us to understand treatment response or resistance. Knowledge gained from this investigation will help us to improve the design of future immunotherapy-based regimens with curative potential for patients.
Grant: 6534-18 | Translational Research Program (TRP):
Location:Yale University, New Haven, Connecticut 06520-8327
Project Title: Exploiting Mutant IDH1/2-induced BRCAness With PARP Inhibitors As A Novel AML/MDS Therapy.Project Summary:
We have identified a novel approach to treat certain types of leukemias that harbor a mutation in key genes that are involved in cellular metabolism. We found that these mutations create an altered chemical in the cell, which blocks the ability of tumor cells to repair broken DNA. This "achilles heel" can be exploited by treating such tumors with DNA damaging agents combined with DNA repair inhibitors. We have already demonstrated that this therapeutic approach is highly effective in brain tumors and other solid cancers which harbor mutations in these genes, and we now seek to determine whether the same is true in leukemias. Current strategies to treat tumors with these mutations are focused on suppressing the production of the altered metabolite. Our data suggest that this approach actually may not be ideal, as the metabolic vulnerability should be exploited rather than suppressed. The studies proposed here represent a highly translational, cross-disciplinary collaboration between researchers in hematology and oncology, radiation oncology, small molecule screening, and DNA repair basic science research. We expect that these studies will directly lead to a novel clinical trial in the future for leukemias with these mutations.
Grant: 6536-18 | Translational Research Program (TRP):
Location:The University of North Carolina at Chapel Hill, Atlanta, Georgia 30384-2420
Project Title: Exploiting The Inducible Caspase9 To Pharmacologically Modulate CD19.CAR-T Cell Function In VivoProject Summary:
The administration of a subset of human immune cells cultured in the laboratory and known as T lymphocytes that have been engineered to express a chimeric molecule that recognizes leukemic cells (CD19.CAR-Ts) has shown remarkable antitumor effects in patients with a blood tumor known as acute lymphoblastic leukemia (ALL). We propose here to improve this therapy by reducing its potentially lethal side effects that are caused by the extreme expansion of these cells once they encounter tumor cells in patients. These side effects are known as 1) cytokine release syndrome, with symptoms varying from flu-like symptoms to more severe side effects such as cardiac arrest, renal failure and ultimately death; 2) seizure and coma that are often life threatening; 3) life-long inability to recover the normal cells of the blood that protect from infections. We have now developed and validated in the laboratory a strategy that allows a precise regulation of the expansion of the T cells in patients, by using an absolutely safe drug that only works on the T cells infused into the patients, thus significantly controlling the cytokine release syndrome. In addition, a slightly higher dose of the same drug can be used to completely eliminate the T cells infused when the patient has achieved a durable elimination of the tumor cells. We now propose to use this strategy to in a phase I clinical trial (LCCC1541-ATL) to determine whether receiving iC9-CAR-Ts cells is safe and tolerable in adult and pediatric subjects with relapsed/refractory ALL and to determine our capacity to control the expansion of the T cells once infused into the patients. We have written the clinical trial, which has received approvals from the various regulatory agencies and validated the production of cells in our specialized manufacturing facility.
Grant: 6531-18 | Translational Research Program (TRP):
Location:The Trustees of Columbia University in the City of New York, Columbia University Medical Center, New York, New York 10027
Project Title: New Therapies In Relapsed ALLProject Summary:
Acute lymphoblastic leukemia (ALL) is an aggressive hematological tumor resulting from the malignant transformation of early lymphoid progenitor cells. Despite intensive chemotherapy, 20% of pediatric and over 50% of adult ALL patients fail to achieve a complete remission or relapse after intensified chemotherapy. Importantly, relapsed ALL is frequently associated with chemotherapy resistance and, despite salvage therapy with intensified treatment, cure rates are still unsatisfactory low. Here we propose to explore the therapeutic role of inosine monophosphate dehydrogenase (IMPDH) inhibitors in the treatment of relapsed and chemotherapy resistant ALL. Specifically we will ask: what is the specific role and mechanisms that mediate the antileukemic effects of IMPDH inhibitors in relapsed leukemia?; What patients would benefit best from treatment with these drugs?; and finally, what drug combinations may enhance the antitumor activity of these therapeutics? These studies will be instrumental for the clinical development of IMPDH inhibitors in the treatment of high risk leukemia.
Grant: 1346-18 | Career Development Program (CDP):
Location:University of Cincinnati, Cincinnati, Ohio 45221-0222
Project Title: The Oncogenic Role And Underlying Mechanism Of TET1 In Acute Myeloid LeukemiaProject Summary:
Acute myeloid leukemia (AML) is one of the most common and fatal forms of hematopoietic malignancies. Thus, it is urgent to better understand the mechanisms underlying the pathogenesis of AML, and on the basis of such understanding, to develop novel therapies with higher efficacy and minimal side effects to treat AML. The properties of cancer are often determined by the proteins that are expressed from information provided by the genes in the cell. Expression of information from genes is regulated in part by chemical modifications of the DNA in the gene, in a process called “epigenetic regulation.” One such modification is called methylation. A family of proteins involved in epigenetic regulation are the 3 TET proteins, which ultimately affect the methylation status of critical genes. TET proteins are traditionally thought to be negative regulators of tumor growth. However, in contrast to this tumor suppressive role, we recently reported that TET1 is highly expressed in certain subtypes of AML, suggesting an opposite role for TET1, the promotion of tumor growth.
We are currently studying the mechanisms by which TET1 promotes tumorigenesis and how we might use this information to develop a novel approach to treat AML. Some central questions are to understand how tumors develop, how they are maintained after they develop, and how the leukemia stem cells provide a reservoir for continued tumor development in a patient. Therefore, we seek to understand the role of TET1 in both the development and maintenance of the AML types that overexpress TET1, and the role of TET1 in the leukemic stem cells. In addition, we are studying the critical target genes that are affected by TET1, which will provide further insight into the role of TET1 in AML. Lastly, we are examining ways to therapeutically target TET1 using mouse models of AML. The success of our studies will provide novel insights into our understanding of the critical role of TET1 in AML and may also lead to the development of novel and more effective therapeutic approaches to treat the AML.
Grant: 5462-18 | Career Development Program (CDP):
Location:Yale University, New Haven, Connecticut 06520-8327
Project Title: A Protein Degradation Approach For The Treatment Of Acute Myeloid LeukemiaProject Summary:
Many cancers result from a genetic mutation causing an “always on” protein. Current treatments are based on the deactivation of the proteins by blocking that protein’s active site. Herein I propose an alternative approach in which proteins are permanently degraded rather than temporarily deactivated, which may prove to be a more favourable form of therapy. To do this, I will take advantage of the cell’s own natural ability to degrade its own proteins when they are in excess or no longer needed. I will design and prepare compounds which recruit the native protein degradation machinery to the target proteins by creating a bridge between protein degradation components and the target protein. This approaches uses a two-headed molecule called a Proteolysis Targeting Chimera (PROTAC).
The potential advantages of protein degradation over protein inhibition are three fold:
1. Constant and complete deactivation of proteins is necessary for a treatment to be successful. Protein inhibition, as happens with standard targeted drugs, is often a reversible process, allowing previously inhibited proteins to again be functional. Protein degradation, as happens with PROTACs, is irreversible, therefore resulting in complete deactivation.
2. PROTACs have shown the potential to be catalytic, meaning one PROTAC molecule could destroy more than one protein molecule, preventing cells from simply producing more protein to overcome the deactivation of the existing population.
3. An issue arising from current treatments is the development of resistance after treatment for a relatively short period of time. The proposed PROTAC compounds may be able to circumnavigate such resistance mechanisms.
I propose to prepare PROTACs containing recognition elements for target proteins involved in blood cancers. Specifically, I am focusing on FLT3, which is a protein important in about 1/3 of all AMLs. I will assess PROTACs for the ability to degrade target proteins in cell-based models. The resulting compounds will then be optimised before progression into animal models. It is conceivable that by employing protein degradation, it may be possible to completely remove all disease causing protein. The ultimate goal is to produce a drug that may be useful for the treatment of AML containing FLT3 mutations. Importantly, PROTAC technology has applicability in a number of different cancers.
Grant: 1344-18 | Career Development Program (CDP):
Location:Fred Hutchinson Cancer Research Center, Seattle, Washington 98109-1024
Project Title: The Biological And Therapeutic Consequences Of SF3B1 Mutations In Myelodysplastic SyndromesProject Summary:
Myelodysplastic syndromes (MDS) are a group of blood disorders characterized by impaired differentiation of hematopoietic stem cells into functional blood cells. MDS frequently has a poor prognosis and is associated with a high risk of transformation into acute myeloid leukemia. There are few treatment options for MDS, largely because the underlying molecular changes that drove MDS were not known until recently.
Recent genome sequencing studies revealed that MDS and related diseases are associated with specific mutations (genetic changes) in hematopoietic stem cells. These mutations most commonly affect genes that control a molecular process termed "RNA splicing." RNA splicing is critical to the process by which genetic information in DNA is "read" to make proteins. We now know that MDS-associated mutations that affect RNA splicing cause mistakes during the transfer of genetic information from DNA to protein. However, we do not yet know precisely which mistakes ultimately give rise to MDS.
We plan to use both experimental and computational methods to determine how mutations that affect RNA splicing give rise to MDS. Understanding the specific molecular changes that occur in MDS cells carrying these mutations will enable us to identify potential new therapeutic opportunities for treating MDS. Because the same mutations affecting RNA splicing are found in other blood diseases as well, such as chronic lymphocytic leukemia, we hope that our discoveries will improve the treatment of many different blood diseases.