Department of Urology, Peking University Shenzhen Hospital, Shenzhen, Guangdong 518036, PR China; The Guangdong and Shenzhen Key Laboratory of Male Reproductive Medicine and Genetics, Peking University Shenzhen Hospital, Institute of Urology of Shenzhen PKU-HKUST Medical Center, Shenzhen, Guangdong 518036, PR China. Electronic address: