Docetaxel, as a taxane antimitotic drug, inhibits the androgen receptor (AR) transcriptional activity by promoting the binding of transcription factor forkhead box protein O1 (FOXO1) to AR promoter in the prostate cancer cell nucleus, thereby down-regulating the expression of AR and prostate-specific antigen (PSA) and ultimately promoting tumor cell apoptosis [8, 9]. This evidence concerns the gene KLK3 and prostate cancer.