目的：探讨miR1425p对多柔比星诱导的原发性肝细胞癌（hepatocellular carcinoma，HCC）细胞凋亡的影响及其作用机制。方法：收集广西医科大学附属肿瘤医院88例HCC患者手术切除的癌组织及癌旁组织（距癌灶组织边缘2～5 cm）标本。采用实时荧光定量PCR 检测人HCC组织和癌旁组织、人正常肝细胞以及HCC细胞系中miR1425p 的表达量。向HCC细胞SMMC7721中转染miR1425p mimics，流式细胞术检测过表达miR1425p后SMMC7721细胞在多柔比星（doxorubicin）（1 μg/ml）诱导下凋亡的变化；生物信息学方法预测miR1425p可靶向结合胰岛素样生长因子2 mRNA结合蛋白3(insulinlike growth factor 2 mRNAbinding protein 3, IGF2BP3)基因，并采用荧光素酶报告基因实验进行验证。采用实时荧光定量PCR及Western blotting检测过表达miR1425p的SMMC7721细胞中IGF2BP3的mRNA及蛋白表达情况。结果：与癌旁组织和正常肝细胞相比，HCC组织 (-6.91±2.61 vs -11.59±2.59，P<0.01)和多种HCC细胞系中miR1425p呈明显低表达（均P<0.01)；过表达miR1425p可显著促进多柔比星诱导的HCC细胞SMMC7721的凋亡\[(49.40±3.47)% vs (19.50±174)%，P<0. 01\]；过表达miR1425p可明显降低HCC细胞中IGF2BP3的mRNA及蛋白表达水平(P<0.01)，敲减IGF2BP3表达可进一步促进多柔比星诱导的SMMC7721细胞的凋亡（P<0.01)。荧光素酶报告基因实验结果显示，miR1425p能够抑制 IGF2BP3的3′UTR荧光素酶报告基因的活性。结论：miR1425p在HCC组织标本和体外培养细胞系中的表达水平均显著降低,转染miR1425p mimics后能够促进多柔比星诱导的HCC细胞的凋亡，其机制可能与miR1425p靶向作用IGF2BP3从而促进HCC细胞凋亡有关。

Objective:To investigate the function and molecular mechanisms of micro RNA1425p ( miR1425p) on the doxorubicin induced apoptosis of primary hepatocellular carcinoma (HCC)．Methods: Paired HCC tissues and adjacent noncancerous tissue specimens (25cm away from the lesion) were surgically collected from 88 patients who were diagnosed with primary HCC in Tumor Hospital Affiliated to Guangxi Medical University between October 2001 and July 2005. qRTPCR was used to detect the miR1425p expressions in those HCC tissues, adjacent noncancerous tissues, normal hepatocellular cell line and HCC cell lines. HCC SMMC7721 cells were transfected with miR1425p mimics, and flow cytometry was used to determine the changes in doxorubicin (1 μg/ml) induced apoptosis of SMMC7721 cells. Bioinformatics predicted that miR1425p could bind with insulinlike growth factor 2 Mrnabinding protein 3 (IGF2BP3), which was then validated by luciferase reporter gene assay. qRTPCR and Western blotting were separately used to detect the mRNA and protein expressions of IGF2BP3 in SMMC7721 cells that overexpress miR1425p. Results: Compared with the adjacent nontumor tissues, miR1425p was significantly lower in HCC tissues (-6.91±261 vs -11.59±259, P<0.01) and this decrease was also found in HCC cell line compared with normal human liver cells (P<0.01); overexpression of miR1425p significantly promoted the doxorubicin induced apoptosis of HCC SMMC7721 cells (\[49.4±3.47\]% vs \[19.50±1.74\]%, P<0.01). miR1425p overexpression could obviously inhibit the mRNA and protein expressions of IGF2BP3 in SMMC7721 cells. Luciferase reporter gene assay also showed that miR1425p overexpression could inhibit the luciferase activity of 3′UTR of IGF2BP3. Conclusion: miR1425p expression significantly decreased in both HCC tissues and HCC cell lines. miR1425p mimics transfection promoted doxorubicin induced apoptosis of HCC cells, and the mechanism probably related with miR1425p targetting IGF2BP3 and further promote the apoptosis of HCC cells.

国家自然科学基金资助项目（No.31390431）；国家重点基础研究发展规划（973计划）资助项目(No. 2013CB530503)