Specifically, Sisi He et al. reported that high CYP27A1 expression was associated with shortened progression-free survival for ovarian cancer patients, and the expression of CYP27A1 was critical for the infiltration of monocytic myeloid derived suppressor cells to support tumor growth in an ovarian cancer mouse model (He et al., 2019). Here, CYP27A1 is linked to ovarian cancer.