PT  - JOURNAL ARTICLE
AU  - NINOMIYA, YASUHARU
AU  - IMAOKA, TATSUHIKO
AU  - DAINO, KAZUHIRO
AU  - KAKINUMA, SHIZUKO
AU  - NAKAJIMA, TETSUO
TI  - Arsenite-induced Radiosensitization of Glioma Cells Is Dependent on p53 Deficiency
AID  - 10.21873/anticanres.16422
DP  - 2023 Jun 01
TA  - Anticancer Research
PG  - 2551--2559
VI  - 43
IP  - 6
4099  - http://ar.iiarjournals.org/content/43/6/2551.short
4100  - http://ar.iiarjournals.org/content/43/6/2551.full
SO  - Anticancer Res2023 Jun 01; 43
AB  - Background/Aim: Arsenite is a radiosensitizer of glioma cells both in vitro and in vivo; however, the underlying mechanism of action is unclear. Radiosensitizers specific for p53-deficient tumors are a promising adjunct to radiotherapy because, unlike normal cells, many tumor cells lack p53. Previously, we demonstrated that arsenite sensitizes the p53-deficient glioma cell line U87MG-E6 to X-rays. Materials and Methods: Using flowcytometry, we expand these findings to p53-proficient U87MG cells exposed to heavy ion beams, including carbon and iron ions. Results: Arsenite sensitized U87MG-E6, but not U87MG, cells to heavy ion beams and X-rays. Cell cycle analysis indicated that sensitization of U87MG-E6 was related to an increase in the percentage of cells in the late S/G2/M phases after combined treatment with arsenite, especially when carbon ion beams were used. Induction of γH2AX was significant in U87MG-E6, but not in U87MG, cells after irradiation with carbon ion beams plus arsenite. Conclusion: Arsenite sensitizes cells by increasing the percentage of cells in the late S/G2/M phases after irradiation, possibly via inhibition of DNA repair in the context of p53 deficiency. The findings provide information that may be useful for the development of advanced radiotherapy protocols.