PRSS21 and neoplasm: Tang et al. (2005) found that PRSS21 mRNA is overexpressed in ovarian tumors but has restricted expression in normal human tissues other than the testis. However, Conway et al. (2019) unexpectedly discovered that increased PRSS21 activity has a minor impact on cell proliferation but inhibits intraperitoneal tumor metastasis, resulting in a significantly reduced tumor burden.