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目的:探讨miRNA-296-5p（miR-296-5p）对缺氧诱导的胰腺癌细胞迁移、侵袭的影响及其相关机制。方法:选择人胰腺癌细胞株PANC-1；收集上海市奉贤区中心医院和蚌埠医学院附属第一医院2010年1月至2014年12月55例胰腺癌患者手术切除的胰腺癌组织和10例癌旁正常胰腺组织。采用免疫组织化学及原位杂交法检测胰腺癌及癌旁正常胰腺组织芯片中缺氧诱导因子1α（HIF-1α）、miR-296-5p的表达水平，分析二者的相关性及其与患者临床病理特征的关系。PANC-1细胞分为缺氧组和常氧组，采用Transwell法测定两组细胞迁移与侵袭能力，实时荧光定量聚合酶链反应（qRT-PCR）检测两组细胞miR-296-5p及HIF-1α mRNA表达。转染小干扰RNA（siRNA）干扰HIF-1α的表达，将细胞分为PANC-1组（空白对照）、PANC-1-NC组（阴性对照）、PANC-1-siRNA组，检测miR-296-5p的表达；同时转染miR-296-5p激动剂和抑制剂，分为Agomir-miR-296-5p组（激动剂组）、Agomir-miR-296-5p-NC组（激动剂阴性对照组）、Antagomir-miR-296-5p组（抑制剂组）、Antagomir-miR-296-5p-NC组（抑制剂阴性对照组）；Transwell法检测各组细胞迁移和侵袭能力。采用荧光素酶报告基因系统验证miR-296-5p启动子区是否存在HIF-1α的结合位点。结果:胰腺癌组织HIF-1α高表达率高于癌旁正常胰腺组织[81.8%（45/55）比0（0/10），n P<0.01]；胰腺癌组织miR-296-5p高表达率低于癌旁正常胰腺组织[12.7%（7/55）比90.0%（9/10），n χ2=27.23，n P<0.01]。HIF-1α表达和miR-296-5p表达呈负相关（n r=-0.53，n P<0.01）；miR-296-5p低表达与肿瘤长径、TNM分期、淋巴结转移均有关（均n P<0.05）。常氧组PANC-1侵袭细胞数为（15.3±2.1）个，缺氧组为（24.7±1.5）个，差异有统计学意义（n t=0.26，n P=0.003）；常氧组PANC-1迁移细胞数为（20.7±3.8）个，缺氧组为（32.7±1.2）个，差异有统计学意义（n t=5.25，n P=0.006）。常氧组PANC-1细胞HIF-1α mRNA相对表达量为0.30±0.02，缺氧组为1.00±0.01，差异有统计学意义（n t=56.45，n P<0.01）；常氧组PANC-1细胞miR-296-5p相对表达量为3.05±0.20，缺氧组为1.14±0.04，差异有统计学意义（n t=16.05，n P<0.01）。PANC-1组、PANC-1-NC组、PANC-1-siRNA组侵袭细胞数分别为（24.7±1.5）个、（25.7±1.5）个、（12.0±1.7）个，差异有统计学意义（n F=68.13，n P<0.01），PANC-1-siRNA组较PANC-1组细胞侵袭能力下降（n t=9.50，n P=0.001）；迁移细胞数分别为（32.7±1.2）个、（37.0±1.0）个、（17.3±1.2）个，差异有统计学意义（n F=262.09，n P<0.01），PANC-1-siRNA组较PANC-1组细胞迁移能力下降（n t=16.26，n P<0.01）。Antagomir-miR-296-5p组与PANC-1组比较，细胞侵袭和迁移能力增强（均n P<0.05）；Agomir-miR-296-5p组与PANC-1组比较，细胞侵袭和迁移能力减弱（均n P<0.05）。荧光素酶报告基因系统检测荧光素酶活性结果显示，miR-296-5p存在与HIF-1α结合的靶点。n 结论:HIF-1α通过负向调控miR-296-5p在缺氧诱导的胰腺癌细胞的侵袭、迁移中发挥重要作用。“,”Objective:To investigate the effect of miRNA-296-5p (miR-296-5p) on the migration and invasion of hypoxia-induced pancreatic cancer cells and its related mechanisms.Methods:Human pancreatic cancer cell line PANC-1 was selected. Pancreatic cancer tissues from 55 pancreatic cancer patients who underwent the resection and adjacent carcinoma normal pancreatic tissues from 10 patients at Shanghai Fengxian District Central Hospital and Bengbu Medical College First Affiliated Hospital between January 2010 and December 2014 were collected. The expression levels of hypoxia-inducible factor 1α (HIF-1α) and miR-296-5p in tissue microarray of pancreatic cancer and adjacent carcinoma normal pancreatic tissues were detected by using immunohistochemistry and in situ hybridization. The relationship between miR-296-5p and HIF-1α as well as their correlation with clinicopathological characteristics of patients were analyzed. PANC-1 cells were divided into hypoxic group and normoxic group. Transwell assay was used to detect the cell migration and invasion ability of both groups. Real-time quantitative polymerase chain reaction (qRT-PCR) was used to examine the expressions of HIF-1α and miR-296-5p under hypoxic environment of both groups. The expression of HIF-1α was interfered by transfecting small interfering RNA (siRNA). PANC-1 cells were divided into PANC-1 group (the empty control), PANC-1-NC group (the negative control) and PANC-1-siRNA group. The expression of miR-296-5p was measured. After co-transfecting miR-296-5p agonist and miR-296-5p inhibitor, the cells were divided into Agomir-miR-296-5p group (agonist group), Agomir-miR-296-5p-NC group (agonist negative control group), Antagomir-miR-296-5p group (inhibitor group) and Antagomir-miR-296-5p-NC group (inhibitor negative control group). Transwell assay was used to detect the cell migration and invasion ability of all groups. Luciferase reporter gene system was used to verify whether miR-296-5p promoter region had binding site of HIF-1α.Results:The high expression rate of HIF-1α in pancreatic cancer tissues was higher than that of adjacent carcinoma normal pancreatic tissues [81.8% (45/55) vs. 0 (0/10),n P<0.01], and the high expression rate of miR-296-5p in pancreatic cancer tissues was lower than that of adjacent carcinoma normal pancreatic tissues [12.7% (7/55) vs. 90.0% (9/10),n χ2 = 27.23, n P<0.01]. The expression of HIF-1α was negatively correlated with that of miR-296-5p (n r = -0.53, n P<0.01). The low expression of miR-296-5p was closely related with the tumor diameter, TNM staging, lymph node metastasis (alln P<0.05). The number of PANC-1 invasion cell was 15.3±2.1 in normoxic group and 24.7±1.5 in hypoxic group, and the difference was statistically significant (n t = 0.26, n P = 0.003). The number of PANC-1 migration cell was 20.7±3.8 in hypoxic group and 32.7±1.2 in normoxic group, and the difference was statistically significant (n t = 5.25, n P = 0.006). The relative expression level of HIF-1α mRNA in PANC-1 cell of hypoxic group was higher than that of normoxic group [(1.00±0.01) vs. (0.30±0.02)], and the difference was statistically significant (n t = 56.45, n P<0.01); the relative expression level of miR-296-5p in PANC-1 cell of hypoxic group was lower than that of normoxic group [(1.14±0.04) vs. (3.05±0.20)], and the difference was statistically significant (n t = 16.05, n P<0.01). The number of invasion cells in PANC-1 group, PANC-1-NC group and PANC-1-siRNA group was 24.7±1.5, 25.7±1.5, 12.0±1.7, respectively, and the difference was statistically significant (n F = 68.13, n P<0.01).The cell invasion ability in PANC-1-siRNA group was decreased compared with that in PANC-1 group (n t = 9.50, n P = 0.001). The number of cell migration was 32.7±1.2, 37±1.0, 17.3±1.2, respectively in PANC-1 group, PANC-1-NC group and PANC-1-siRNA group, and the difference was statistically significant (n F = 262.09, n P<0.01). The cell migration ability in PANC-1-siRNA group was decreased compared with that in PANC-1 group (n t = 16.26, n P<0.01). The cell invasion and migration ability in Antagomir-miR-296-5p group was increased compared with that in PANC-1 group (alln P<0.05); the cell invasion and migration ability in Agomir-miR-296-5p group was decreased compared with that in PANC-1 group (alln P<0.05). The results of luciferase activity detected by luciferase reporter gene system showed that miR-296-5p had the target binding to HIF-1α.n Conclusions:HIF-1α plays a key role in the invasion and migration of hypoxia-induced pancreatic cancer cells through negatively reducing miR-296-5p.