Combination Targeted Therapy in Relapsed Diffuse Large B-Cell Lymphoma.

BACKGROUND: The identification of oncogenic mutations in diffuse large B-cell lymphoma (DLBCL) has led to the development of drugs that target essential survival pathways, but whether targeting multiple survival pathways may be curative in DLBCL is unknown. METHODS: We performed a single-center, phase 1b-2 study of a regimen of venetoclax, ibrutinib, prednisone, obinutuzumab, and lenalidomide (ViPOR) in relapsed or refractory DLBCL. In phase 1b, which included patients with DLBCL and indolent lymphomas, four dose levels of venetoclax were evaluated to identify the recommended phase 2 dose, with fixed doses of the other four drugs. A phase 2 expansion in patients with germinal-center B-cell (GCB) and non-GCB DLBCL was performed. ViPOR was administered every 21 days for six cycles. RESULTS: In phase 1b of the study, involving 20 patients (10 with DLBCL), a single dose-limiting toxic effect of grade 3 intracranial hemorrhage occurred, a result that established venetoclax at a dose of 800 mg as the recommended phase 2 dose. Phase 2 included 40 patients with DLBCL. Toxic effects that were observed among all the patients included grade 3 or 4 neutropenia (in 24% of the cycles), thrombocytopenia (in 23%), anemia (in 7%), and febrile neutropenia (in 1%). Objective responses occurred in 54% of 48 evaluable patients with DLBCL, and complete responses occurred in 38%; complete responses were exclusively in patients with non-GCB DLBCL and high-grade B-cell lymphoma with rearrangements of MYC and BCL2 or BCL6 (or both). Circulating tumor DNA was undetectable in 33% of the patients at the end of ViPOR therapy. With a median follow-up of 40 months, 2-year progression-free survival and overall survival were 34% (95% confidence interval [CI], 21 to 47) and 36% (95% CI, 23 to 49), respectively. CONCLUSIONS: Treatment with ViPOR was associated with durable remissions in patients with specific molecular DLBCL subtypes and was associated with mainly reversible adverse events. (Funded by the Intramural Research Program of the National Cancer Institute and the National Center for Advancing Translational Sciences of the National Institutes of Health and others; ClinicalTrials.gov number, NCT03223610.).

Androgen responsive and refractory prostate cancer cells exhibit distinct curcumin regulated transcriptome.

Curcumin (diferuloylmethane) is the major active component of turmeric and is being actively investigated for its anti-cancer properties. To better understand the biological mechanisms of the chemopreventive potential of curcumin in prostate cancer, we have evaluated curcumin regulated transcriptome in prostate cancer cells. Hierarchical clustering methods and functional classification of the Curcumin-Gene Expression Response (Cu-GER) showed temporal co-regulation of genes involved in oxidative stress response and growth signaling pathways. Interestingly, C4-2B, androgen independent metastatic prostate cancer cells exhibited attenuated Cu-GER response in comparison to parental androgen dependent and less aggressive LNCaP cells. Androgen Receptor (AR) regulated genes which play critical roles in normal growth and differentiation of the prostate gland, as well as in prostate cancer, were also a part of the Cu-GER. Of note, curcumin downregulated transcript encoded by the potentially causal TMPRSS2-ERG gene fusion, a common oncogenic alteration noted in 50-70% of prostate cancer patients. Further more, expression of EGFR and ERBB2 receptor were found to be downregulated in curcumin treated LNCaP and C4-2B cells. This report for the first time establishes novel features of Cu-GER in prostate cancer cells of varying tumorigenic phenotypes and provides potentially novel read-outs for assessing effectiveness of curcumin in prostate cancer and likely in other cancers. Importantly, new gene-networks identified here further delineate molecular mechanism(s) of action of curcumin in prostate cancer cells.

A role for DNA methylation in regulating the growth suppressor PMEPA1 gene in prostate cancer.

A cascade of epigenetic events contributes to the selective growth advantage of cancer cells during tumor progression. PMEPA1 gene is an androgen-inducible negative regulator of cell growth in the prostate epithelium. During prostate cancer progression PMEPA1 gene transcription is reduced or lost prompting us to investigate the role of epigenetic events in this process. In LAPC4 cells harboring wild type androgen receptor decitabine (5-aza-2'-deoxycitidine) treatment resulted in increased expression of PMEPA1 along with other androgen-inducible genes, suggesting a role for DNA methylation in the repression of androgenic cell growth control signals in prostate cancer. In contrast, mutant androgen receptor expressing LNCaP cells were deficient in this response. Therefore, decitabine-induced expression of cell growth controlling genes such as NKX3.1 or PMEPA1 underlines the clinical applicability of decitabine in prostate tumors harboring wild type androgen receptor. Further analysis of DNA methylation within the PMEPA1 promoter downstream sequences suggests that methylation of SP1 binding sites may also contribute to the repression of PMEPA1 gene.