However, restoration of CYP27A1 expression inhibited the progression of T24 and UM-UC-3 bladder cancer cells, suggesting that CYP27A1 could inhibit bladder cancer cell proliferation by regulating cholesterol homeostasis49.Similarly, in patients with renal clear cell carcinoma, CYP27A1 could inhibit tumor proliferation and metastasis by activating the LXRs/ABCA1 axis52, which provides a new idea for anti-tumor therapy in the future. Here, ABCA1 is linked to neoplasm.