Characterization of a Novel Small Molecule Subtype Specific Estrogen-Related Receptor α Antagonist in MCF-7 Breast Cancer Cells

The orphan nuclear receptor estrogen-related receptor alpha (ERRalpha) is a member of the nuclear receptor superfamily. It was identified through a search for genes encoding proteins related to estrogen receptor alpha (ERalpha). An endogenous ligand has not been found. Novel ERRalpha antagonists that are highly specific for binding to the ligand binding domain (LBD) of ERRalpha have been recently reported. Research suggests that ERRalpha may be a novel drug target to treat breast cancer and/or metabolic disorders and this has led to an effort to characterize the mechanisms of action of N-[(2Z)-3-(4,5-dihydro-1,3-thiazol-2-yl)-1,3-thiazolidin-2-yl idene]-5H dibenzo[a,d][7]annulen-5-amine, a novel ERRalpha specific antagonist.We demonstrate this ERRalpha ligand inhibits ERRalpha transcriptional activity in MCF-7 cells by luciferase assay but does not affect mRNA levels measured by real-time RT-PCR. Also, ERalpha (ESR1) mRNA levels were not affected upon treatment with the ERRalpha antagonist, but other ERRalpha (ESRRA) target genes such as pS2 (TFF1), osteopontin (SPP1), and aromatase (CYP19A1) mRNA levels decreased. In vitro, the ERRalpha antagonist prevents the constitutive interaction between ERRalpha and nuclear receptor coactivators. Furthermore, we use Western blots to demonstrate ERRalpha protein degradation via the ubiquitin proteasome pathway is increased by the ERRalpha-subtype specific antagonist. We demonstrate by chromatin immunoprecipitation (ChIP) that the interaction between ACADM, ESRRA, and TFF1 endogenous gene promoters and ERRalpha protein is decreased when cells are treated with the ligand. Knocking-down ERRalpha (shRNA) led to similar genomic effects seen when MCF-7 cells were treated with our ERRalpha antagonist.We report the mechanism of action of a novel ERRalpha specific antagonist that inhibits transcriptional activity of ERRalpha, disrupts the constitutive interaction between ERRalpha and nuclear coactivators, and induces proteasome-dependent ERRalpha protein degradation. Additionally, we confirmed that knocking-down ERRalpha lead to similar genomic effects demonstrated in vitro when treated with the ERRalpha specific antagonist

Abemaciclib in combination with pembrolizumab for HR+, HER2- metastatic breast cancer: Phase 1b study.

This nonrandomized, open-label, multi-cohort Phase 1b study (NCT02779751) investigated the safety and efficacy of abemaciclib plus pembrolizumab with/without anastrozole in patients with hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-) metastatic breast cancer (MBC) without prior CDK4 and 6 inhibitor exposure. Patients were divided into two cohorts: treatment naïve (cohort 1) and pretreated (cohort 2). Patients received abemaciclib plus pembrolizumab with (cohort 1) or without (cohort 2) anastrozole over 21-day cycles. The primary objective was safety, and secondary objectives included efficacy and pharmacokinetics (PK). Cohort 1/2 enrolled 26/28 patients, respectively. Neutropenia (30.8/28.6%), AST increase (34.6/17.9%), ALT increase (42.3/10.7%), and diarrhea (3.8/10.7%) were the most frequent grade ≥3 adverse events in cohort 1/2, respectively. A total of two deaths occurred, which investigators attributed to treatment-related adverse events (AEs), both in cohort 1. Higher rates of all grade and grade ≥3 interstitial lung disease (ILD)/pneumonitis were observed compared to previously reported with abemaciclib and pembrolizumab monotherapy. The PK profiles were consistent between cohorts and with previous monotherapy studies. In cohorts 1/2, the overall response rate and disease control rate were 23.1/28.6% and 84.6/82.1%, respectively. Median progression-free survival and overall survivals were 8.9 (95% CI: 3.9-11.1) and 26.3 months (95% CI: 20.0-31.0) for cohort 2; cohort 1 data are immature. Abemaciclib plus pembrolizumab demonstrated antitumor activity, but high rates of ILD/pneumonitis and severe transaminase elevations occurred with/without anastrozole compared to the previous reporting. Benefit/risk analysis does not support further evaluation of this combination in the treatment of HR+, HER2- MBC.We thank the patients and families who participated in this study, caregivers, the study investigators, and their staff, and the JPCE (NCT02779751) clinical trial team. Pembrolizumab was provided by Merck & Co., Inc., Kenilworth, NJ, USA. We thank Anne Chain from the Department of Quantitative Pharmacology & PharmacometricsImmune/Oncology, Merck & Co., Inc., Kenilworth, NJ, USA for her contributions to this work, which included pembrolizumab PK and ADA analysis. This work and medical writing support was funded by Eli Lilly and Company.S

Tisotumab Vedotin in Combination with Carboplatin, Pembrolizumab, or Bevacizumab in Recurrent or Metastatic Cervical Cancer:Results from the innovaTV 205/GOG-3024/ENGOT-cx8 Study

PURPOSE Tissue factor is highly expressed in cervical carcinoma and can be targeted by tisotumab vedotin (TV), an antibody-drug conjugate. This phase Ib/II study evaluated TV in combination with bevacizumab, pembrolizumab, or carboplatin for recurrent or metastatic cervical cancer (r/mCC). METHODS This open-label, multicenter study (ClinicalTrials.gov identifier: NCT03786081) included dose-escalation arms that assessed dose-limiting toxicities (DLTs) and identified the recommended phase II dose (RP2D) of TV in combination with bevacizumab (arm A), pembrolizumab (arm B), or carboplatin (arm C). The dose-expansion arms evaluated TV antitumor activity and safety at RP2D in combination with carboplatin as first-line (1L) treatment (arm D) or with pembrolizumab as 1L (arm E) or second-/third-line (2L/3L) treatment (arm F). The primary end point of dose expansion was objective response rate (ORR). RESULTS A total of 142 patients were enrolled. In dose escalation (n = 41), no DLTs were observed; the RP2D was TV 2 mg/kg plus bevacizumab 15 mg/kg on day 1 once every 3 weeks, pembrolizumab 200 mg on day 1 once every 3 weeks, or carboplatin AUC 5 on day 1 once every 3 weeks. In dose expansion (n = 101), the ORR was 54.5% (n/N, 18/33; 95% CI, 36.4 to 71.9) with 1L TV + carboplatin (arm D), 40.6% (n/N, 13/32; 95% CI, 23.7 to 59.4) with 1L TV + pembrolizumab (arm E), and 35.3% (12/34; 19.7 to 53.5) with 2L/3L TV + pembrolizumab (arm F). The median duration of response was 8.6 months, not reached, and 14.1 months, in arms D, E, and F, respectively. Grade ≥3 adverse events (≥15%) were anemia, diarrhea, nausea, and thrombocytopenia in arm D and anemia in arm F (none ≥15%, arm E).CONCLUSION TV in combination with bevacizumab, carboplatin, or pembrolizumab demonstrated manageable safety and encouraging antitumor activity in treatment-naive and previously treated r/mCC.</p

RNAi screen for NRF2 inducers identifies targets that rescue primary lung epithelial cells from cigarette smoke induced radical stress

Chronic Obstructive Pulmonary Disease (COPD) is a highly prevalent condition characterized by inflammation and progressive obstruction of the airways. At present, there is no treatment that suppresses the chronic inflammation of the disease, and COPD patients often succumb to the condition. Excessive oxidative stress caused by smoke inhalation is a major driving force of the disease. The transcription factor NRF2 is a critical player in the battle against oxidative stress and its function is impaired in COPD. Increasing NRF2 activity may therefore be a viable therapeutic option for COPD treatment. We show that down regulation of KEAP1, a NRF2 inhibitor, protects primary human lung epithelial cells from cigarette-smoke-extract (CSE) induced cell death in an established in vitro model of radical stress. To identify new potential drug targets with a similar effect, we performed a siRNA screen of the 'druggable' genome using a NRF2 transcriptional reporter cell line. This screen identified multiple genes that when down regulated increased NRF2 transcriptional activity and provided a survival benefit in the in vitro model. Our results suggest that inhibiting components of the ubiquitin-proteasome system will have the strongest effects on NRF2 transcriptional activity by increasing NRF2 levels. We also find that down regulation of the small GTPase Rab28 or the Estrogen Receptor ESRRA provide a survival benefit. Rab28 knockdown increased NRF2 protein levels, indicating that Rab28 may regulate NRF2 proteolysis. Conversely ESRRA down regulation increased NRF2 transcriptional activity without affecting NRF2 levels, suggesting a proteasome-independent mechanism

Figure S1 from Results of an Open-label, Phase Ia/b Study of Pembrolizumab plus Olaratumab in Patients with Unresectable, Locally Advanced, or Metastatic Soft-Tissue Sarcoma

Figure S1: Study design.</p

Table S4 from Results of an Open-label, Phase Ia/b Study of Pembrolizumab plus Olaratumab in Patients with Unresectable, Locally Advanced, or Metastatic Soft-Tissue Sarcoma

Table S4: Representativeness of Study Participants.</p

Table S2 from Results of an Open-label, Phase Ia/b Study of Pembrolizumab plus Olaratumab in Patients with Unresectable, Locally Advanced, or Metastatic Soft-Tissue Sarcoma

Table S2: Dose reduction, delay, and omission due to AE.</p