目的 探讨褪黑素（MLT）体内外对胃癌Th1/Th2/Th17型细胞因子干扰素（IFN）-γ、肿瘤坏死因子（TNF）、白细胞介素（IL）-2、IL-4、IL-6、IL-10、IL-17a表达的影响。 方法 1.构建荷胃癌小鼠模型，共32只雄性615小鼠全部荷小鼠前胃癌（MFC）细胞后随机分为4组，分别用0、25、50、100 mg/kg剂量褪黑素进行腹腔注射并测量肿瘤长短径。干预1周后取外周血，剥离肿瘤组织进行称重和测量。2.将MFC接种于6孔细胞培养板中，贴壁24 h后分别用0、2、4、6、8、10 mmol/L浓度褪黑素干预，24 h后形态学观察并收集相应上清液。3.采用ELISA检测外周血清中褪黑素的浓度变化。采用流式液相多重蛋白定量技术流式微珠阵列（CBA）分别检测外周血清、细胞上清液中Th1/Th2/Th17型相关细胞因子的浓度变化。 结果 1.成功建立荷胃癌小鼠模型。与阴性对照组相比， 褪黑素中、高剂量组小鼠外周血清褪黑素浓度明显升高，肿瘤体积明显下降。与阴性对照组相比，中剂量组血清中IL-10浓度明显增加；高剂量组血清IFN-γ、IL-2、IL-10浓度均明显增加。2.褪黑素干预MFC细胞实验中，与空白对照组相比，6、10 mmol/L 褪黑素组中IFN-γ浓度显著降低；4、6、8、10 mmol/L 褪黑素组中IL-6浓度明显降低，而 6 mmol/L 褪黑素组IL-10浓度明显升高。以上差异均具有统计学意义（P<0.05）。 结论 褪黑素体内外对胃癌细胞均有抑制作用且可能通过调节Th1/Th2/Th17细胞相关因子IFN-γ、IL-2、IL-6及IL-10的表达起增强肿瘤免疫作用。

Objective To investigate the effect of melatonin(MLT) on the expression of type Th1/Th2/Th17 cytokines such as interferon(IFN)-γ, tumor necrosis factor(TNF), interleukin(IL)-2,IL-4,IL-6,IL-10,IL-17a and so on of gastric cancer in vitro and in vivo. Methods 1. Model of gastric cancer-bearing mice was established. Then 32 male 615 mice were all inoculated with murine foregastric carcinoma cells and randomly divided into 4 groups, and injected intraperitoneally with melatonin at doses of 0, 25, 50 and 100 mg/kg, and measureed long and short diameter of tumor, respectively. After a week of intervention, peripheral blood was taken and the tumor tissue was removed for weighing and measurement. 2. Murine foregastric carcinoma (MFC)cells were inoculated into a six-well cell culture plate and routinely cultured. After 24 hours of adherence, they were treated with melatonin at different concentrations of 0, 2, 4, 6, 8 and 10 mmol/L. After 24 hours again, the cells morpology were observed and the corresponding supernatants were collected. 3. The expressions of melatonin concentrations in peripheral blood serum was detected by enzyme -linked imm unosorbent assay (ELISA). The expressions of Th1/Th2/Th17 cytokines in peripheral blood serum and cell supernatants were detected by cytometric bead array (CBA) respectively. Results 1. Tumor-bearing mice models were successfully established. Compared with the negative control group, the melatonin concentration in peripheral blood serum of the middle and high dose MLT group which increased significantly, and the tumor volume significantly decreased. Compared with the negative control group, the concentration of IL-10 in the middle dose group increased significantly. And the concentration of IFN-γ, IL-2 and IL-10 in the high dose group increased significantly too. 2. Compared with the 0 mmol/L MLT group, the concentrations of IFN-γ in the 6 and 10 mmol/L MLT group were significantly decreased; the concentrations of IL-6 in the 4, 6, 8 and 10 mmol/L MLT group were significantly decreased, and the concentration of IL-10 in 6 mmol/L MLT group was significantly increased. All the difference were statistically significant (P<0.05). Conclusion Melatonin inhibits the proliferation of murine foregastric carcinoma cell MFC both in vitro and in vivo, and may enhance tumor immunity by adjust the expression of IFN-γ, IL-2, IL-6 and IL-10 cytokines of type Th1/Th2/Th17 cells.