Radiosensitizing effects of novel benzothiadiazole derivatives on KRAS-mutant non-small cell lung cancers / 国际生物医学工程杂志

ABSTRACT

Objective To investigate the radiosensitization effects and mechanisms of novel benzothiadiazole derivatives HL-095 to KRAS-mutant non-small cell lung cancer ( NSCLC ) H358 , A549 , and H460 cell lines . Methods The benzothiadiazole derivative HL-095 was designed and synthesized with AZD6244 as the lead compound. The ability of HL-095 to inhibit the activity of MEK kinase was detected by the mitogen-activated extracellular signal-regulated kinase 1 (MEK1). H358, A549 and H460 cells were inoculated and cultured at appropriate density, and divided into control group, HL-095 group, irradiation group and HL-095 combined irradiation group. One-time irradiation with 137Cs gamma rays was used with a dose rate of 1.02 Gy/min. The expression of phosphorylated extracellular regulatory protein kinase ( p-ERK ) in H358 , A549 and H460 cells was detected by Western Blot. The cell proliferation was detected by cloning assay. The degree of DNA damage was analyzed by Comet assay. The G2/M phase cells were detected by flow cytometry. The level of the checkpoint kinase 1 (CHK1) protein and its phosphorylation in A549 and H358 cells was detected by Western Blot. Results HL-095 can inhibit the activity of MEK1. Compared with the control group, the expression levels of p-ERK protein of H358, A549, and H460) cells in HL-095 group were decreased, the percentages of cells in the G2/M phase were also decreased, and the differences were statistically significant (all P<0.01). The expression and phosphorylation of CHK1, a key protein of DNA damage repair, was down-regulated in A549 and H358 cells. Compared with the irradiated group, the proliferation of the three kinds of cell in HL-095 combined irradiation group was inhibited, the DNA damage was more serious, the Olive tail moment, tail length, tail length and tail DNA percentage were significantly increased, and the differences were statistically significant (all P<0.05). Conclusion As a MEK inhibitor, the novel benzothiadiazole derivative HL-095 can enhance the radiosensitivity of KRAS mutant NSCLC cells by inhibiting DNA damage repair and reducing G2/M arrest.