On the other hand, multiple studies revealed that the expression of TMPRSS2 was found to be considerably down‐regulated in tumour tissues compared to non‐tumorous ones, and abnormal expression of TMPRSS2 was closely related to tumour growth, invasion, metastasis and prognosis in various cancers, especially prostate cancer.19, 20. The gene discussed is TMPRSS2; the disease is Familial prostate cancer.