PCSK5 and breast cancer: Notably, with exception of BRAF, a well-known PTC driver gene, this study was the first to identify several genes with high frequency mutations in PTC, such as NCOR2, ANK3, BPTF, and PCSK5. A previous study reported that NCOR2, a nuclear receptor corepressor, serves as a potential drug target in the treatment of breast cancer by interacting with ER, and deficiency of NCOR2 may cause breast cancer (43).