A growing body of evidence further regards HAI-2 as a tumor suppressor, and its down-regulation is linked to poor prognosis in various cancers, including hepatocellular carcinoma, melanoma, esophageal squamous cell carcinoma, gastric cancer, renal cell carcinoma, prostate cancer, cervical cancer, medulloblastoma and ovarian cancer58–68. Here, SPINT2 is linked to prostate cancer.