Moreover, inhibition of cellular proliferation via down‐regulation of cyclin B1, p‐AR, PSA, CDK1, p‐AKT, c‐Myc, p‐CDK1 (T161) expression levels and up‐regulation of p53 in PC3 prostate cancer cells by green tea extract was detected. This evidence concerns the gene CCNB1 and prostate carcinoma.