Effect of hyperthermia on the biological functions of human lung cancer cell line H1299 and its molecular mechanism

Objective To explore the influences on biological function induced by hyperthermia in human lung cancer cell line H1299, and to investigate the possible molecular mechanism. Methods H1299 cells were cultured in vitro and divided into 2 groups. The cells in culture flasks of hyperthermia group were immersed into a water bath at 43 ℃ for 1 h, and the cells of control group were cultured at 37 ℃. The cell growth was detected by CCK8 assay, and the cell cycle and apoptosis rates were detected by flow cytometry [propidium iodide (PI) staining and PI/Annexin V staining]. The effects of hyperthermia on migration and invasion abilities of H1299 cells were determined by Transwell migration and invasion assays, respectively. The expression of LLGL1 was measured by Western blot. Results The cell cycle had no significant difference between the two groups, but the apoptosis rate was significantly higher in hyperthermia group [(24.81±2.80)%] than that in control group [(11.73±1.55)%] (t= 7.709, P= 0.002 1). The migrating cell number was decreased in hyperthermia group (25.67±4.81) than that in control group (85.00±10.31) (t= 5.182, P= 0.006 6). The invasive cell number was also decreased in hyperthermia group (22.00±2.08) than that in control group (108.3.0±10.14) (t= 8.342, P= 0.001 1). The expression level of LLGL1 protein in hyperthermia group was 4.2 times that in control group(t= 3.028, P= 0.038 9). Conclusion Hyperthermia induces the cell apoptosis and inhibits migration and invasion abilities of H1299 cells, which maybe associate with increasing LLG1 expression. Key words: Lung neoplasms; Hyperthermia, induced; Apoptosis; LLGL1; Invasion