Radiosensitizing effects of Sestrin2 in PC3 prostate cancer cells

Objective(s): The stress-responsive genes of Sestrin family are recognized as new tumor suppressor genes in breast carcinoma, however, the function of Sestrin family in human prostate cancer is not clear. Ionizing radiation (IR) is known to induce Sestrin gene expression in breast cancer cells. However, the response of Sestrin to IR has not been reported in PC3 prostate cancer cells. Materials and Methods: Sestrin2 expression in prostate cancer cell lines (PC3, LNCaP clone FGC, and DU145) was detected by Western blot and real-time PCR. Cell counting kit (CCK-8) was used to detect cellular proliferation. The radiosensitivity of PC3 cells was detected by clonogenic assay. Results: Sestrin2 expression in prostate cancer cell lines (PC3, LNCaP clone FGC, and DU145) is low. In vitro assays indicated that over-expressing Sestrin2 in human prostate cancer PC3 inhibited tumor proliferation. In addition, elevated Sestrin2 expression sensitized PC3 cells to IR. Conclusion: We determined Sestrin2 may function as a tumor suppressor through repressing proliferation, mediating sensitization to IR in PC3 cells.