B-cell chronic lymphocytic leukemia [B-CLL] is a human neoplastic disorder characterized by the progressive accumulation of quiescent B lymphocyte. We have hypothesized that B CLL arises primarily because of failures in the normal mechanisms of cell turnover through programmed cell death, rather than as a result of alterations in cell cycle regulation, and that anomalies in the expression and function of apoptosis-regulatory proteins are the critical obstacle to the successful treatment of this malignancy. The overall goal of the biochemistry component of the B-CLL Research Consortium [CRC] is to define the fundamental abnormalities of apoptosis regulation in B-CLL, and to devise targeted treatments that address the basic problems. During the previous funding period, our experiments have demonstrated that several pro-apoptotic proteins [including Bax, BH3-only proteins such as Bim, caspases] are abundantly expressed in B-CLL but are maintained in an inactive state by the concomitant high-level expression of specific anti-apoptotic proteins [including Bcl-2, Mcl-1, lAPs, FLIP]. Accordingly, the specific hypothesis to be tested in this renewal application is that chemical agents that release pro-apoptotic proteins from inhibitory complexes will trigger apoptosis of B-CLL cells, or render these malignant cells more susceptible to cytotoxic therapy or immunotherapy. Working in collaboration with members of the CRC and other scientists, we have identified several new agents that can overcome in vitro some of the apoptosis defects in B-CLL. These prototype compounds have been demonstrated to block Bcl-2 interaction with BH3 proteins, to reverse IAP inhibition of caspases, or to release the BH3-only protein Bim from microtubules. The focus of the planned experiments in the CRC grant renewal is to continue our preclinical analysis of these prototype therapeutics, testing their efficacy against cultured CLL B-cells, improving our understanding of their mechanisms of action, and optimizing approaches for employing these agents, in hope of rapidly bringing these concepts and the new agents into the clinic.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Research Program Projects (P01)
Project #
5P01CA081534-11
Application #
8068810
Study Section
Subcommittee G - Education (NCI)
Project Start
Project End
Budget Start
2010-05-01
Budget End
2011-04-30
Support Year
11
Fiscal Year
2010
Total Cost
$386,950
Indirect Cost
Name
University of California San Diego
Department
Type
DUNS #
804355790
City
La Jolla
State
CA
Country
United States
Zip Code
92093
Barr, Paul M; Robak, Tadeusz; Owen, Carolyn et al. (2018) Sustained efficacy and detailed clinical follow-up of first-line ibrutinib treatment in older patients with chronic lymphocytic leukemia: extended phase 3 results from RESONATE-2. Haematologica 103:1502-1510
Kondo, K; Shaim, H; Thompson, P A et al. (2018) Ibrutinib modulates the immunosuppressive CLL microenvironment through STAT3-mediated suppression of regulatory B-cell function and inhibition of the PD-1/PD-L1 pathway. Leukemia 32:960-970
Hasan, Md Kamrul; Yu, Jian; Widhopf 2nd, George F et al. (2018) Wnt5a induces ROR1 to recruit DOCK2 to activate Rac1/2 in chronic lymphocytic leukemia. Blood 132:170-178
Ten Hacken, Elisa; Valentin, Rebecca; Regis, Fara Faye D et al. (2018) Splicing modulation sensitizes chronic lymphocytic leukemia cells to venetoclax by remodeling mitochondrial apoptotic dependencies. JCI Insight 3:
Gribben, John G (2018) How and when I do allogeneic transplant in CLL. Blood 132:31-39
Sivina, Mariela; Werner, Lillian; Rassenti, Laura et al. (2018) Dynamic changes in CCL3 and CCL4 plasma concentrations in patients with chronic lymphocytic leukaemia managed with observation. Br J Haematol 180:597-600
Ott, Christopher J; Federation, Alexander J; Schwartz, Logan S et al. (2018) Enhancer Architecture and Essential Core Regulatory Circuitry of Chronic Lymphocytic Leukemia. Cancer Cell 34:982-995.e7
Balatti, Veronica; Tomasello, Luisa; Rassenti, Laura Z et al. (2018) miR-125a and miR-34a expression predicts Richter syndrome in chronic lymphocytic leukemia patients. Blood 132:2179-2182
Vangapandu, Hima V; Chen, Huiqin; Wierda, William G et al. (2018) Proteomics profiling identifies induction of caveolin-1 in chronic lymphocytic leukemia cells by bone marrow stromal cells. Leuk Lymphoma 59:1427-1438
Yu, Jian; Chen, Yun; Chen, Liguang et al. (2018) Cirmtuzumab inhibits ibrutinib-resistant, Wnt5a-induced Rac1 activation and proliferation in mantle cell lymphoma. Oncotarget 9:24731-24736

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