Research we fund

The b-catenin/BCL9 transcriptional complex, is a novel dependency in multiple myeloma (MM). Disruption of this complex inhibits MM cell growth in culture and in MM xenograft models. Development of potent selective b-catenin/BCL9 inhibitors will provide valuable tools to further investigate their mechanism of MM inhibition. We have established a chemistry, structural biology, and molecular pathology platform to facilitate novel inhibitor development, and explore its translational potential in MM.

This proposal is to conduct a phase I (early phase) clinical trial to test whether the combination of the approved targeted therapy venetoclax with memory-like Natural Killer (NK) cells is safe and active in patients with acute myeloid leukemia (AML). Based on laboratory research at Dana-Farber Cancer Institute, we believe that the addition of memory-like NK cells obtained from an haploidentical (‘half matched’) donor will be able to eradicate residual leukemia cells left over after prior venetoclax treatment and hence prevent a future relapse of the disease. A total of 10 patients will be treated with two different doses of NK cells and a constant dose of venetoclax. We also plan scientific studies on patient samples to learn more about the function of NK cells when combined with venetoclax, evaluate for clearance of residual leukemia cells with this combination therapy and explore potential resistance mechanisms.

We will develop a novel T cell therapy strategy for multiple myeloma (MM) that will combine existing chimeric antigen receptors (CARs) with a novel designed biosensor responding to soluble factors abundantly present in the MM bone marrow environment in patients. The biosensor will be expressed as novel type of chimeric receptor in T cells concomitantly with the CAR and signal the T cells to persist longer and keep eliminating cancer cells from the body. We will deeply characterize the effects of our novel biosensor in CAR T cells to precisely understand how the treatment works. If successful, we expect that CAR T cell therapy for MM can be made more efficient, and the same strategy could potentially also be applied to other cancer types.

Although they represent a major therapeutic progress for blood cancers, CAR-T cells and other T-cell based therapies are subject to eventual development of resistance to many patients. Natural killer (NK) cell-based therapies are highly active against many types of blood cancer cells which are resistant to T cells, but in our CRISPR studies death receptor signaling defects emerge as a common downstream mechanism of resistance to both T- and NK-cell therapies. Building on extensive pharmacological and genomic screens, this project will specifically examine the role of SMAC mimetics and JAK/STAT inhibitors in enhancing the response of blood cancer cells (e.g., multiple myeloma, leukemias) to CAR-T or NK cell therapies. We will place emphasis of studies with patient-derived samples in vitro (Integrated Functional Immune Profiling Platform) and in vivo, including humanized bone marrow-like scaffolds, to provide a translationally-relevant simulation of the potential of these compounds to enhance the clinical activity of cell-based immunotherapies in blood cancers.

Our laboratory and those of others discovered highly recurring mutations in the gene MYD88 which are found in patients with various B-cell cancers including Waldenstrom’s Macroglobulinemia (95-97%), ABC Subtype of Diffuse B-cell Lymphoma (30-40%), Primary Central Nervous Lymphoma (80%), Marginal Zone Lymphoma (10%) and Chronic Lymphocytic Leukemia (5-10%). Our laboratory and those of others showed that mutated MYD88 triggers BTK, which is the target of BTK-inhibitors like ibrutinib, acalabrutinib and zanubrutinib though complete remissions are rare with these agents largely in part because other pro-survival molecules are activated by mutated MYD88 such as HCK and IRAK1. In these studies, we will develop potent and selective inhibitors to HCK and IRAK1, including PROTACs which inhibit and degrade these molecules, using lead molecules and scaffolds whose target selectivity and activity we previously validated. We will also investigate the mechanisms underlying the inactivation of the Inhibitor of BTK (IBTK) as a potential new target for development of inhibitors for use in MYD88 mutated lymphomas.

Inhibition of a tumor-triggered immune exhaustion pathway, termed PD-1 blockade, enables immune effector cells to attack cancers. In classic Hodgkin Lymphoma (cHL), PD-1 blockade is now a standard treatment for relapsed disease and a component of experimental frontline therapy. We have identified a major population of monocyte/macrophages in patients with cHL that inhibit tumor cell killing and limit the efficacy of PD-1 blockade. Our goal is to fully characterize these tumor-specific monocytes/macrophages and target their immunosuppressive and tumorigenic program for therapeutic benefit in patients with cHL and other lymphoid malignancies.

Niclosamide is an FDA approved anti-parasitic drug that is well tolerated and acts synergistically with chemotherapy to kill AML cells. We will conduct a Phase I clinical trial with niclosamide in combination with cytarabine for children with relapsed/refractory pediatric AML. ShRNA/CRISPR screens demonstrated that Bcl-2 is upregulated in niclosamide resistant cells. We will study the effects of the Bcl-2 inhibitor venetoclax in combination with niclosamide in pediatric AML.

Few treatment options are available for T cell leukemias and lymphomas, collectively called T cell cancers that affect ~100,000 patients worldwide each year. The current proposal will generate new antibodies attached to drugs and toxins that kill the T cell cancers. Importantly, the antibodies will preserve enough healthy T cells to maintain a functioning immune system. These modified antibodies may improve patient outcome and limit side effects associated with traditional chemotherapies.

The mitogen-activated protein kinase (MAPK) pathway is activated in high-risk leukemia and is a hallmark of resistance to therapies. This project uses patient-derived xenograft models of relapsed pediatric ALL and AML with activated RAS/MAPK to test whether clinically relevant MAPK mutations activate the VAV3/RAC pathway and if pharmacological inhibition of that pathway by a small molecule we developed synergizes with a MAPK-inhibitor to provide a new treatment strategy for RAS-driven leukemia.

T-cell ALL is an aggressive blood cancer with poor overall survival, high relapse rates, and significant treatment-related side effects. Using primary T-ALL patient samples, this project will study the importance of JAK/STAT signaling and the gene BIRC5 in the pathology of T-ALL driven by DNMT3A mutations using genetic and pharmacological tools. The goal of this proposal is to develop precision medicine approaches for DNMT3A-mutant adult T-ALL patients, a group with poor clinical outcomes

Clonally expanded T cells carrying somatic mutations circulate in the premalignant phase of Adult T cell leukemia/lymphoma (ATL). We will develop capture-sequencing of recurrent ATL-driver mutations for use as a diagnostic tool for the detection/characterization of ATL-like clones in individuals with high risk of ATL, and, in an aligned clinical study, we will test whether a novel monoclonal antibody (targeting C-C chemokine receptor 4) can eradicate these high-risk cells.

Advances in multiple myeloma (MM) therapy have improved survival, but serial cycles of response and relapse still lead to treatment-refractory and fatal disease in nearly all patients. To specifically target mechanisms of MM relapse, we propose to develop an immunotherapy targeting Sox2, a stem-cell transcription factor implicated in clonogenic MM growth that enables relapse.