CYP27A1 and cancer: Similarly, expression of CYP27A1 is reduced in clinical specimens in bladder cancer, prostate cancer and renal cell carcinoma, and restoration of its expression is able to inhibit the proliferation of these cancer cell lines, indicating its potential role as a tumor suppressor (Riecanský and Plachá, 1983; Alfaqih et al., 2017; Baek et al., 2017; Liang et al., 2019; Zhang X. et al., 2022).