【摘要】 目的 基于低氧诱导因子1α（HIF-1α）/白细胞介素8（IL-8）信号通路探讨二甲双胍对食管鳞状细胞癌（ESCC）细胞的体内外抑制作用及机制。方法 将人食管鳞癌细胞TE1分为空白组，二甲双胍低、中、高浓度组（0.5、1、2 mmol/L）,IDF-11774（HIF-1α抑制剂）组（20μmol/L）和二甲双胍高浓度+HIF-1α激活剂二甲基乙二酰氨基乙酸（DMOG）组（2 mmol/L二甲双胍和10μmol/L DMOG）。处理24 h后，检测细胞增殖[以5-乙炔基-2’脱氧尿嘧啶核苷（EdU）阳性率和光密度(OD₄₅₀值)计]、凋亡、侵袭、迁移情况以及细胞中增殖细胞核抗原（PCNA）、Bcl-2相互作用的细胞死亡介质（Bim）、迁移侵袭增强因子1（MIEN1）、基质金属蛋白酶9（MMP-9） mRNA表达和HIF-1α、IL-8蛋白表达。构建裸鼠移植瘤模型。将30只裸鼠随机分为空白组，二甲双胍低、中、高剂量组（灌胃62.5、125、250 mg/kg二甲双胍并腹腔注射等体积生理盐水），IDF-11774组（灌胃50 mg/kg IDF-11774并腹腔注射等体积生理盐水）和二甲双胍高剂量+DMOG组（灌胃250 mg/kg二甲双胍并腹腔注射250 mg/kg DMOG），每组5只。每天给药1次，持续4周后，检测小鼠瘤体质量、体积及肿瘤组织中HIF-1α、IL-8蛋白表达。结果 二甲双胍可呈浓度/剂量依赖性地降低/减少TE1细胞的EdU阳性率、OD₄₅₀值、侵袭数、划痕愈合率以及细胞中PCNA mRNA、MIEN1 mRNA、MMP-9 mRNA、HIF-1α蛋白、IL-8蛋白表达水平和移植瘤瘤体质量、体积及肿瘤组织中HIF-1α、IL-8蛋白表达水平（P<0.05），升高细胞凋亡率和细胞中Bim mRNA表达水平（P<0.05）;IDF-11774组对应指标变化趋势与二甲双胍组一致，而DMOG能显著减弱高浓度/剂量二甲双胍的上述作用（P<0.05）。结论 二甲双胍可抑制TE1细胞增殖、侵袭、迁移及裸鼠体内移植瘤生长，诱导细胞凋亡；其机制可能与抑制HIF-1α/IL-8信号通路有关。更多还原

【Abstract】 OBJECTIVE To explore the in vitro and in vivo inhibitory effects and mechanism of metformin on the malignant biological behavior of esophageal squamous cell carcinoma（ESCC） cells by the hypoxia inducible factor-1α（HIF-1α）/interleukin-8（IL-8） signaling pathway. METHODS Human ESCC TE1 cells were assigned into blank group, metformin low-, medium-, and high-dose groups（0.5, 1, 2 mmol/L）, IDF-11774（HIF-1α inhibitor） group（20 μmol/L）, and high-dose metformin+HIF-1α activator dimethyloxalylglycine（DMOG） group. After 24 h treatment, cell proliferation [measured by the positive rate of 5-ethynyl-2’-deoxyuridine（EdU） and optical density at 450 nm(OD₄₅₀ value)], apoptosis, invasion and migration as well as mRNA expressions of proliferating cell nuclear antigen（PCNA）, Bcl-2 interacting mediator of cell death（Bim）, migration and invasion enhancer 1（MIEN1）, and matrix metalloproteinase-9（MMP-9）, and protein expressions of HIF-1α and IL-8 in the cells were detected. The xenograft tumor model of nude mice was established. Thirty nude mice were randomly divided into blank group, metformin low-, medium-, and high-dose groups（i. g. administration of metformin 62.5, 125, 250 mg/kg+i. p. administration of equal volume of normal saline）, IDF-11774 group（i.g. administration of 50 mg/kg IDF-11774+i.p. administration of equal volume of normal saline） and high-dose metformin+DMOG group（i. g. administration of metformin 250 mg/kg+i. p. administration of DMOG 250 mg/kg）, with 5 mice in each group. They were given relevant medicine, once a day, for 4 consecutive weeks; the mass and volume of the tumor and protein expressions of HIF-1α and IL-8 in the tumor tissue were determined. RESULTS The EdU positive rate, OD₄₅₀ value, cell invasion number, scratch healing rate, mRNA expressions of PCNA, MIEN1 and MMP-9, protein expressions of HIF-1α and IL-8, as well as the mass and volume of transplanted tumors and protein expressions of HIF-1α and IL-8 in tumor tissues were decreased by metformin in concentration/dose-dependent manner（P<0.05）. Additionally, metformin increased the apoptosis rate and mRNA expression of Bim in cells（P<0.05）. The trend of changes in corresponding indicators in the IDF-11774 group was consistent with that in the metformin groups, whereas DMOG could significantly attenuate the aforementioned effects of high-concentration/high-dose metformin（P<0.05）. CONCLUSIONS Metformin can inhibit the proliferation, invasion, migration of TE1 cells, and tumor growth of nude mice, and induce cell apoptosis, the mechanism of which may be related to the inhibition of HIF-1α/IL-8 signaling pathway.更多还原