The Chromatin Remodeler Chromodomain Helicase DNA Binding Protein 2 Promotes Colorectal Cancer Progression

Integrative analysis of colorectal cancer (CRC) whole genomes and matched transcriptomes revealed that somatic promoter mutations are associated with increased Chromodomain helicase DNA-binding protein 2 (CHD2) levels. In both primary and metastatic CRC patients, elevated CHD2 levels are associated with worse prognosis and overall survival. We find that CHD2 increases promoter-transcription start site-chromatin accessibility and transcriptional upregulation of multiple oncogenes. In vitro, elevated CHD2 promoted CRC cell proliferation, migration and growth. In orthotopic xenografts, CHD2 promoted higher tumor burden and abdominal metastases, most prominently to the liver. FTD/TPI is an FDA approved chemotherapy for advanced chemo-refractory CRC. In orthotopic CRC models, FTD/TPI was highly effective in reducing metastases and prolonging survival for CHD2 high expressing CRCs. Thus, high CHD2 expression may be a potential CRC chemopredictive biomarker for FTD/TPI. Overall, these results provide new insights into the role of non-coding mutations and CHD2 levels to promote CRC growth and metastasis.