Schäffer, Alejandro A.

Abstract Approximately 50% of prostate cancer (PCa) patients harbor fusions involving the TMPRSS2 and ERG genes. Despite this, tailored therapies targeting the fused gene, tERG , remain undeveloped. Our study analyzed biopsy samples from two clinical trials assessing the efficacies of androgen receptor (AR) signaling inhibitors (ARSIs). The results revealed that tERG promotes resistance to ARSIs and is associated with elevated levels of the glucocorticoid receptor (GR). Subsequent assays showed that GR directly interacts with tERG, alleviates allosteric autoinhibition and prevents chemotherapy-induced tERG degradation. In PCa models, either inhibiting GR or lowering cortisol levels suppressed tumor growth in tERG-positive models, but not in fusion-negative models. In addition, patient-derived fusion-positive xenografts displayed enhanced sensitivity to combined GR and AR inhibitors. Collectively, these findings highlight TMPRSS2-ERG as a new biomarker and propose that simultaneous inhibition of GR and AR may specifically benefit tERG -positine patients. However, GR stimulatory corticosteroid therapies may not be advisable for this patient subgroup.

Abstract Systematic multiomic analysis has revealed ancestry-dependent molecular alterations, but their impact on the efficacy of anticancer treatment is yet largely unknown. In this study, we analyzed clinical trials from ClinicalTrials.gov and found that only 8,779/102,721 (8.5%) oncology clinical trials posted information on enrollment by race/ethnicity. The underrepresentation of non-White populations suggests that it remains challenging to determine differences in the efficacy of antitumor treatments among different racial groups. Through a comprehensive analysis of clinically actionable genes, imputed drug responses, and immune features, we identified potential differences in treatment responses to targeted therapy, chemotherapy, and immunotherapy between different ancestral populations. Further analysis of multiple independent cohorts confirmed some of our key findings. Such potential ancestral effects are also identified in response to emerging new treatments like chimeric antigen receptor T-cell therapy and proteolysis-targeting chimeras. These findings are made publicly available in a comprehensive web portal, Ancestral Differences of Efficacy in Cancers (https://hanlaboratory.com/ADEC), to facilitate their further investigation. Significance: Our study charts a global landscape of ancestry-associated differences in therapeutic efficacy, highlighting the importance of considering ancestry in anticancer therapies.