AR and Familial prostate cancer: AR is the androgen receptor, and AR signalling pathway is related to many hormone‐dependent diseases such as prostate cancer,49 breast cancer50, 51, 52 and ovarian cancer,53 as well as malignant tumours, for example gastric cancer,54, 55 lung cancer,56, 57 bladder cancer,58, 59 pancreatic cancer,60, 61 liver cancer62 and kidney cancer.63