Relationship between telomere length and radiosensitivity of human cancer cell lines induced by heavy ion irradiation.

Our previous works showed that carbon-ion irradiation of MCF-7 cells exhibited elevated radiosensitivity with DNA-PKcs inhibition. Inhibition of DNA-PKcs combined with carbon-ion radiation led to accelerated telomere loss and senescence. However, direct evidences supporting that telomere length was related to radiosensitivity were needed. In this year, MCF-7 cells with shorter telomere length were established by continuous incubation with specific telomerase inhibitor MST-312. MCF-7 cells with shorter telomere were found to be more susceptive to carbon-ion irradiation. Carbon-ion radiation alone induced G2-M cell cycle arrest, while combined with MST-312 incubation, the cell cycle arrest shift to G1-S arrest. Current data supported the telomere length was related to radioresistance in cancer cells.平成24年度HIMAC共同利用研究成果発表会