Influence of hyperthermia on cell cycle and rhythm gene Bmall expression in gastric cancer MKN28 cells

Objective To investigate the relationship between the cell cycle blocked by hyperthermia and the expression of rhythm gene Bmall in gastric cancer MKN28 cells so as to provide the academic evidence in hyperthermia therapy for gastric cancer. Methods The MKN28 cells were resuscitated and cultured in vitro.In control group MKN28 cells were cultivated at 37 ℃.In experimental groups MKN28 cells were heated at 43 ℃ for different durations.The cell morphology was observed by microscopy.Methylthiazdyl tetrazolium (MTT) assay was adopted to evaluate the inhibitory effect of the cell line.The flow-cytometry was adopted to observe the influence on the cell cycle.The Bmall mRNA expression was investigated by real-time quantitative reverse transcription-polymerase chain reaction ( RT-PCR). Results The remarkable changes of cell morphology were observed by microscopy after exposure to heating.According to the data of MTT assay,37 ℃ heating could not inhibit the proliferation of MKN28.The inhibitive rates of cell growth after 0.5 h,1 h,l.5 h at 43 ℃ was (21.76±5.46)％,(25.30 ±4.36)％ and (27.62 ± 3.78 )％,respectively.Results from flow-cytometry showed that G0/G1 phase cells in lh at 43 ℃ were remarkably less than those in the control group.However G2/M cells were significantly more than those in the control group.The mRNA expression of Bmall was the lowest when heating lh at 43 ℃ as compared to the control group.Conclusions Hyperthermia could induced the cell cycle changes and the expression of Bma11 in gastric cancer MKN28 cells. Key words: Hyperthermia;  Gastric cancer MKN28 cell;  Rhythm gene Bmall ;  Cell cycle