褪黑素对小鼠H22细胞增殖及pRB和E2F-1表达的影响

EFFECT OF MELATONIN ON H22 HEPATOCARCINOMA CELL PROLIFERATIONAND EXPRESSION OF pRB AND E2F-1 PROTEINS IN MICE

目的探讨褪黑素(melatonin,MLT)对小鼠H22细胞增殖的影响及其抗肿瘤作用机制。方法在Balb/c小鼠腹腔中复苏H22细胞,体外培养,分为3组进行试验生理盐水组、10-6mol/LMLT组和10-9mol/LMLT组,每12h加药一次。采用MTT法分析MLT对小鼠H22细胞增殖的影响;流式细胞术(flowcytometry,FCM)检测细胞周期时相分布;免疫组织化学方法检测体外培养H22细胞株和移植瘤组织pRB和E2F1的蛋白水平。结果1.MTT法表明MLT对小鼠H22细胞增殖有明显的抑制作用,并有剂量依赖性;2.FCM显示MLT可引起H22细胞G0/G1期细胞比例升高,S期细胞比例降低;3.免疫组织化学分析显示MLT处理H22细胞使pRB水平降低,E2F1水平升高。结论MLT可抑制H22细胞的增殖,其机理可能是通过上调E2F1、下调pRB,将细胞周期阻滞在G0/G1期。

? Objective To investigate the effect of melatonin on H22 hepatocarcinoma cells and its anticancer mechanism.Methods H22 cells were resuscitated in the abdominal cavity of Balb/c mice, cultured in vitro, and then divided into three groups: control, 10 -6 mol/L MLT and 10 -9 mol/L MLT. MTT assay was used to assess the effect of melatonin on mice H22 hepatocarcinoma cells. The distribution of H22 cell cycle was demonstrated by flow cytometry (FCM), and the levels of pRB and E2F 1 in cultured H22 cells and transplanted tumors were tested by immunohistochemistry. Results (1) MTT assay indicated that melatonin significantly inhibited the growth of H22 cells in a dose dependent manner. (2) FCM showed that cells at phase G 0 /G 1 increased and thoseat phase S decreased. (3) Immunohistochemistry showed that pRB level decreased while E2F 1 increased after the treatment with melatonin. Conclusion MLT can inhibit the proliferation of H22 hepatocarcinoma cells by up regulating E2F 1 and down regulating pRB. 〔