Biochemistry, Biophysics, and Structural Biology Commons^™

Therapeutic Targeting Of C-Terminal Binding Protein In Human Cancer, Michael W. Straza, Seema Paliwal, Ramesh C. Kovi, Barur R. Rajeshkumar, Peter Trenh, Daniel Parker, Giles F. Whalen, Stephen Lyle, Celia A. Schiffer, Steven R. Grossman

Celia A. Schiffer

The CtBP transcriptional corepressors promote cancer cell survival and migration/invasion. CtBP senses cellular metabolism via a regulatory dehydrogenase domain, and is antagonized by p14/p19(ARF) tumor suppressors. The CtBP dehydrogenase substrate 4-methylthio-2-oxobutyric acid (MTOB) can act as a CtBP inhibitor at high concentrations, and is cytotoxic to cancer cells. MTOB induced apoptosis was p53-independent, correlated with the derepression of the proapoptotic CtBP repression target Bik, and was rescued by CtBP overexpression or Bik silencing. MTOB did not induce apoptosis in mouse embryonic fibroblasts (MEFs), but was increasingly cytotoxic to immortalized and transformed MEFs, suggesting that CtBP inhibition may provide a suitable …