目的：探讨微小RNA（miR）-765对Ⅱ型多磷酸肌醇4-磷酸酶（inositol polyphosphate 4-phosphatase type Ⅱ，INPP4B）调控及其对肝细胞癌（hepatocellular carcinoma, HCC）细胞增殖的影响。方法：采用实时定量PCR检测8例HCC组织和癌旁组织以及8组HCC细胞株中的miR-765的表达水平；MTT法检测过表达miR-765对HCC细胞增殖的影响；利用分子生物学技术构建INPP4B的3′-UTR报告基因，分析miR-765对INPP4B的调控作用，然后采用Western blotting法分别检测过表达和沉默miR-765对INPP4B蛋白表达的影响；应用Western blotting法和克隆形成实验探讨特异性抑制INPP4B对HCC细胞株增殖的影响。结果： 在HCC癌组织以及HCC细胞株中高表达miR-765（P<0.05）。转染miR-765促进HCC细胞的增殖\[（3.78±1.25） vs （2.06±0.47），P<0.05\]。miR-765能够显著下调INPP4B的3′-UTR报告基因的荧光表达\[（0.42±001） vs （1.01±0.01），P<0.05\]，显著上调INPP4B蛋白的表达\[（0.92±0.04) vs (0.42±0.02)、(0.62±0.03)，P<0.05\]。特异性抑制INPP4B后明显促进HCC细胞的增殖\[（238.0±1.73) vs (66.33±5.04)，P<0.05\]。结论：miR-765通过调控INPP4B的表达来促进HCC细胞的增殖。

Objective:To explore the regulating effect of miR-765 on inositol polyphosphate 4-phosphatase type Ⅱ（INPP4B） and its influence on the proliferation of hepatocellular carcinoma cells (HCC). Methods:Quantitative Real-time PCR was used to detect the expression of miR-765 in 8 pairs of HCC tissues and adjacent tissues as well as its expression in 8 sets of hepatocellular carcinoma cell lines. Methyl thiazol tetrazolium (MTT) assay was used to detect the influence of miR-765 over-expression on proliferation of HCC cell line. Molecular biology technique was used to construct 3′-UTR reporter gene of INPP4B, and to analyze the regulation effect of miR-765 on INPP4B; Western blotting was used to examine the effect of miR-765 over-expression/silencing on INPP4B protein expression; Colony formation assay together with Western blotting were applied to investigate the specific inhibition of INPP4B on the proliferation of HCC cell lines. Results: miR-765 was highly expressed in HCC tissues and HCC cells (P<0.05). miR-765-mimics transfection significantly increased the proliferation capacity of HCC cell line (\[3.78±1.25\] vs \[2.06±0.47\], P<0.05) . miR-765 could significantly down-regulate the luciferase expression of pGL3-INPP4B-3′UTR reporter gene (\[042±0.01\] vs \[101±0.01\], P<0.05) and also up-regulate the expression of INPP4B (\[0.92±0.04\] vs \[0.42±0.02\], \[0.62±003\]，P<0.05). Specific inhibition of INPP4B significantly promoted the proliferation of HCC cells (\[238.0±173\] vs \[66.33±5.04\], P<0.05). Conclusion: miR-765 promotes the proliferation of HCC cells by down-regulating INPP4B expression.

江西省科技基金资助项目（No.20151BBG70085）；江西省教育基金资助项目（No.GJJ14681）