CDKN1B and breast cancer: PCBP1 and p27 expression were analyzed by data from GEO database, and high expression of PCBP1 and p27 were observed in Tamoxifen (GSE26459), Doxorubicin (GSE24460) and Lapatinib (GSE16179) sensitive breast cancer subclones (n indicates the analyzed cell subclone numbers).