Abstract PR18: Somatic ERCC2 mutations, nucleotide excision repair (NER) function, and cisplatin response in muscle-invasive bladder cancer (MIBC)

ERCC2 is a core member of the nucleotide excision repair (NER) pathway, a highly conserved and remarkably versatile DNA repair pathway responsible for repairing intrastrand DNA adducts created by genotoxic agents such as UV irradiation and platinum-based chemotherapies. Recent large-scale genomic efforts have shown that somatic ERCC2 missense mutations are present in approximately 20% of all primary muscle-invasive bladder cancers (MIBC). We previously showed that ERCC2 mutations are associated with treatment response and overall survival in MIBC patients treated with cisplatin-based chemotherapy. Initial functional studies on a subset of the observed ERCC2 mutations suggest that the mutations confer loss of normal cellular NER capacity. However, sequencing of additional MIBC cohorts has revealed that mutations occur across the ERCC2 gene, and the functional effects of the majority of these mutations remain unknown. In order to understand the functional landscape of ERCC2 mutations in MIBC, we have developed a high-throughput fluorescence-based assay to test the functional consequences of mutations in ERCC2 and other NER genes on cellular NER capacity. We apply this approach to all observed ERCC2 mutations across three published MIBC cohorts and find that the majority of ERCC2 mutations result in complete or near-complete loss of cellular NER. In addition, by correlating our functional results with available clinical data, we find interesting examples of cases in which ERCC2 ...
Source: Molecular Cancer Research - Category: Cancer & Oncology Authors: Tags: DNA Repair Gene Mutations in Cancer Genomes: Oral Presentations - Proffered Abstracts Source Type: research