摘要目的 研究加热对胃癌MKN28细胞周期变化是否与节律基因Bmall表达相关,为胃癌择时热疗提供理论依据.方法 体外复苏和培养胃癌细胞MKN28；对照组37℃下培养,实验组43℃分别加热0.5h、1.0h和1.5h,用显微镜观察细胞形态变化,采用四甲基偶氮唑盐比色法(MTT)检测细胞增殖抑制率；采用流式细胞术检测细胞周期分布的变化；采用实时定量逆转录-聚合酶链反应( RT-PCR)检测Bmall基因表达变化.结果 加热后细胞形态发生显著变化,MTT实验提示37℃加热对细胞生长无明显抑制,细胞43℃热疗0.5h、1.0h和1.5h后细胞抑制率分别为(21.76 ±4.36)％、(25.30±4.36)％和(27.62±3.78)％,处理后细胞的增殖均受到抑制且抑制趋势具有时间依赖性；流式细胞术显示43℃加热lh后G0/G1最短而G2/M最长,同时实时定量RT-PCR结果显示Bmall mRNA表达最低,细胞周期G0/G1变化规律和Bmall mRNA变化规律一致.结论 热疗可改变胃癌细胞周期及钟基因Bmall表达,提示择时热疗的可行性.

abstractsObjective 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.