Tripartite motif-containing 3 (TRIM3) enhances ER signaling and confers tamoxifen resistance in breast cancer

Abstract Tamoxifen resistance remains a clinical problem in estrogen receptor (ER)-positive breast cancer. SUMOylation of ER? enhances ER?-induced transcription activity. Tripartite motif-containing (TRIM) proteins are new class SUMO E3 ligases, which regulate the proteins. However, precise molecular mechanism and function TRIM3 response to tamoxifen remain unclear. In present study, we observed that was dramatically overexpressed cancer, correlated with resistance. Furthermore, overexpression significantly poor survival patients ER + cancer treated tamoxifen. conferred cell tumorigenesis, whereas knocking down reduced these capabilities. Moreover, TRIM3, as ubiquitin carrier protein 9 (UBC9) binding protein, promoted modification 1 (ESR1) activated pathway. Silencing UBC9 abolished regulating These results suggest novel biomarker for therapy, indicating inhibiting combined might provide potential treatment