An Evidence Based Reporting System for Molecular Tumorboards Identifies Novel Therapeutics for T-Cell Lymphomas

Abstract

Introduction Peripheral T-cell lymphomas (PTCLs) exhibit significant diagnostic and therapeutic challenges. Following current treatment guidelines, the majority of patients either do not achieve a remission or experience an early relapse with fatal outcome. Hence, development of innovative therapeutic strategies targeting the underlying biology of PTCLs is highly demanded. To identify novel therapeutic options for PTCL, we here compiled a comprehensive database of genetic alterations in T-cell lymphomas and utilized bioinformatic methodology for evidence-based reporting of treatment options in the context of molecular tumorboards. Methods Utilizing newly developed bioinformatic methodology for molecular tumorboards1,2, genetic data from >1800 patients with T-cell lymphomas (TCL) compiled from public available sources were analyzed and queried for potential therapeutics addressing genetic alterations in TCL. Based on the results of this approach, a broad in vitro drug screening was performed to assess the activity of potential therapeutics in genetically and transcriptionally characterized cell lines of TCL and address potential biomarkers of response and resistance. Furthermore, functional apoptosis profiling, combination drug screening and mechanistic work up was performed to identify and mechanistically explore novel drug combinations. Results Integration of genetic alterations and drug sensitivity screens revealed novel therapeutic strategies for PTCL. Notably, multiple components of DNA damage response pathways were suggested as therapeutic targets, most prominently the cell cycle regulator WEE1. Indeed, the clinical-grade WEE1 kinase inhibitor, adavosertib, potently induced premature mitotic entry, accumulation of DNA damage and induction of apoptosis in PTCL cell lines, predominantly in cell line models harboring genetic alterations in the ATR signaling pathway. To further enhance the therapeutic effects of WEE1 inhibition, we explored potential combination strategies through mechanistic studies and functional apoptosis profiling. Here, we identified synergistic effects in DNA damage response pathways, cell cycle regulation and modulation of anti-apoptotic proteins through combined WEE1 and JAK/STAT inhibition. Indeed, the combination of adavosertib and ruxolitinib showed marked synergistic cytotoxicity in vitro in genetically characterized subsets of T-cell lymphoma. Conclusions Our results identified WEE1 as a promising therapeutic target for genetically defined PTCL subgroups. Furthermore, mechanistic studies identified concepts for rational combination strategies of WEE1 and JAK/STAT inhibition through modulation of DNA-damage response and priming for apoptosis.