Overexpression of QSOX2 has been found to be associated with poor survival in patients with non‐small cell lung cancer, colorectal cancer, or prostate cancer.[13, 14, 15] Recent research also revealed that recessive mutations in human QSOX2 can cause growth restriction, gastrointestinal dysmotility, and mild immunodeficiency,[31] suggesting that QSOX2 may be related to the development and function of multiple organs in humans. Here, QSOX2 is linked to Familial prostate cancer.