KLK2 and breast cancer: These genes showed only a weak correlation (R = 0.14, p < 7.4e-4), however, CATG00000079217 expression was notably higher in PCa and breast cancer than in other tumors, and it was moderately correlated with several PCa biomarkers (e.g. KLK2, KLK3, STEAP2, PCGEM1, SLC45A3) [42, 43, 49–53] (R = 0.37–0.57, p < 2.2e-16) in TCGA.