The ubiquitinase ZFP91 promotes tumor cell survival and confers chemoresistance through FOXA1 destabilization

The forkhead box A1 (FOXA1), one of the forkhead class of DNA-binding proteins, functions as a transcription factor and plays a vital role in cellular control of embryonic development and cancer progression. Downregulation of FOXA1 has reported in several types of cancer, which contributes to cancer cell survival and chemoresistance. However, the mechanism for FOXA1 downregulation in cancer remains unclear. Here, we report that the ubiquitination enzyme zinc finger protein 91 (ZFP91) ubiquitinates and destabilizes FOXA1, which promotes cancer cell growth. High level of ZFP91 expression correlates with low level of FOXA1 protein in human gastric cancer (GC) cell lines and patient samples. Furthermore, ZFP91 knockdown reduces FOXA1 polyubiquitination, which decreases FOXA1 turnover and enhances cellular sensitivity to chemotherapy. Taken together, our findings reveal ZFP91-FOXA1 axis plays an important role in promoting GC progression and provides us a potential therapeutic intervention in the treatment of GC.