Role of GDF15 in radiosensitivity of breast cancer cells

The Growth Differentiation Factor-15 gene (GDF15) is a member of TGF-b superfamily and this cytokine family is considered to be a promising target for cancer therapy. The purpose of this study was to investigate the effect of tumor derived GDF15 on proliferation and radiosensitivity of breast cancer cells in vitro and in vivo. A mouse breast cancer LM2 cell line with stable transfection of full-length mouse GDF15 cDNA was established. Cell growth and proliferation was observed using WST assay and impedance-based method. Radiation induced GDF15 and TGF-b1 expression was determined by qRT-PCR. Radiosensitivity was measured by a colony formation assay in vitro and by a tumor growth delay assay in vivo. Cells with more than a 10-fold increase in GDF15 expression had a higher growth rate than parental control cells in vitro and in vivo. The radiation induced elevation of the expression of TGFb1 was reduced in GDF15 overexpressing cells. GDF15 may play a role in the radiation response of breast cancer cells by effecting cell survival, inhibiting radiation-induced cell death, and inhibiting the TGF-b1 related cytotoxic action.