褪黑素对荷胃癌小鼠胸腺及脾转化生长因子-β1表达的影响

Effect of melatonin on transforming growth factor-β1 expression in thymus and spleen of mouse with gastric cancer

目的研究褪黑素在抑制肿瘤过程中对荷胃癌小鼠胸腺及脾转化生长因子-β1(TGF-β1)表达变化的影响。方法培养小鼠前胃癌细胞株(MFC),采用小鼠荷胃癌模型。褪黑素用药干预1周后,运用实时荧光定量PCR和免疫组织化学法检测胸腺、脾TGF-β1的表达变化。结果在褪黑素抗肿瘤过程中,与正常对照组相比,荷瘤空白对照组小鼠脾TGF-β1mRNA表达明显下调,胸腺的则无明显变化,且胸腺及脾TGF-β1蛋白表达无明显差异;褪黑素干预后,大剂量组胸腺TGF-β1基因及蛋白表达明显下降,而小剂量组胸腺TGF-β1mRNA表达较荷瘤空白对照组明显升高,差别有统计学意义,小、中、大剂量组脾TGF-β1基因和蛋白表达均回调至正常水平。结论一定浓度褪黑素能够下调荷胃癌小鼠胸腺TGF-β1表达,使荷胃癌小鼠的脾表达下调的TGF-β1回调至正常水平。褪黑素抗胃癌作用与免疫器官中TGF-β1表达变化有关。

Objective To investigate the influence of melatonin on transforming growth factor-β1（TGF-β1） expression in thymus and spleen of mouse,which with gastric cancer.Methods The mice model carrying gastric cancer was set up by inoculating the murine carcinoma cell line（MFC）.After melatonin injection one week,thymus and spleen samples were collected;Then the effect of melatonin on the expression of TGF-β1 in thymus and spleen was detected by using real-time fluorescence quantitative PCR and immunochemistry.Results During the course of tumor inhibition by melatonin,compare with the normal control group,TGF-β1 expression increased in thymus in the tumor-bearing control group,that of spleen has no marked change,and there are no obvious differences of TGF-β1 protein expression in thymus and spleen.After melatonin intervention,TGF-β1 gene and protein expression decreased obviously of thymus in the high-dose melatonin group,but TGF-β1mRNA expression increased obviously of thymus in the lowdose melatonin group compared with the tumor-bearing control group.TGF-β1 gene and protein expression return to normal levels in low,middle,high-dose groups.Conclusion A certain concentration melatonin could down-regulate TGF-β1 expression in thymus of tumor-bearing mice,and make TGF-β1 expression which decreased in tumor-bearing control group return to normal levels of spleen.The inhibition of melatonin on gastric cancer is relative with the changes of TGF-β1 expression in immune organ.