Let-7a enhances the sensitivity of hepatocellular carcinoma cells to cetuximab by regulating STAT3 expression.
Let-7a enhances the sensitivity of hepatocellular carcinoma cells to cetuximab by regulating STAT3 expression.
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Let-7a通过调节STAT3表达增强肝细胞癌细胞对西妥昔单抗的敏感性。
DOI：
10.2147/ott.s116127
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发表时间：
2016
影响因子：
4
通讯作者：
Zhang D
中科院分区：
文献类型：
--
作者：
Xue F;Liu Y;Zhang H;Wen Y;Yan L;Tang Q;Xiao E;Zhang D
Let-7 miRNAs被报道在癌症的发生、肿瘤进展、复发和多能性中发挥抑制作用。然而，很少有研究报道let-7与药物敏感性的关系，特别是let-7a（let-7的一个亚型）。本研究旨在探讨let-7a在调节肝癌细胞对西妥昔单抗敏感性中的作用。在对照、let-7a模拟物和let-7a抑制剂的存在下，使用细胞活力测定（细胞计数试剂盒-8测定）和细胞增殖测定（Click-iT EdU成像试剂盒）评价西妥昔单抗对HCC细胞系（Huh 7、Hep 3B、HepG 2、SNU 449和SNU 387）的细胞毒性。用小干扰RNA（siRNA）敲低信号转导子和转录激活子3（STAT 3）的表达。蛋白质和mRNA的表达水平，采用定量聚合酶链反应和蛋白质印迹分析。发现let-7a增强具有上皮表型的HCC细胞（Huh 7、Hep 3B和HepG 2）对西妥昔单抗的敏感性，但对具有间充质表型的细胞（SNU 449和SNU 387）没有影响。使用TargetScan确定STAT 3是let-7a的靶mRNA。肝癌细胞株中STAT 3和let-7a mRNA表达呈负相关。此外，let-7a改变了STAT 3的蛋白和mRNA表达。此外，STAT 3敲低增强了西妥昔单抗对具有上皮表型的HCC细胞系的功能，但对具有间充质表型的HCC细胞系没有增强。最后，拯救实验证实let-7a通过与STAT 3相互作用影响HCC细胞系对西妥昔单抗的敏感性。let-7a和STAT 3在增强具有上皮表型的HCC细胞对西妥昔单抗的敏感性方面存在功能联系。我们的研究结果为对抗HCC耐药性的新方法提供了新的见解。
Let-7 miRNAs are reported to play an inhibitory role in carcinogenesis, tumor progression, recurrence, and pluripotency of cancer. However, few studies have reported the relationship between let-7 and drug sensitivity, especially for let-7a (a subtype of let-7). This study aimed to investigate the function of let-7a in regulating the sensitivity of hepatocellular carcinoma (HCC) cell lines to cetuximab. The cytotoxicity of cetuximab on HCC cell lines (Huh7, Hep3B, HepG2, SNU449, and SNU387) was evaluated using a cell viability assay (the Cell Counting Kit-8 assay) and a cell proliferation assay (the Click-iT EdU Imaging Kit) in the presence of a control, a let-7a mimic, and a let-7a inhibitor. Small interfering RNA to knockdown the expression of signal transducer and activator of transcription 3 (STAT3) were employed. Protein and mRNA expression levels were determined using quantitative polymerase chain reaction and Western blot analysis. It was found that let-7a enhances the sensitivity of HCC cells with an epithelial phenotype (Huh7, Hep3B, and HepG2) to cetuximab, but has no effect on cells with the mesenchymal phenotype (SNU449 and SNU387). It was determined that STAT3 was a target mRNA of let-7a using TargetScan. Expression of STAT3 and let-7a mRNA were negatively correlated in HCC cell lines. Moreover, let-7a altered the protein and mRNA expression of STAT3. Furthermore, STAT3 knockdown enhanced the function of cetuximab on HCC cell lines with epithelial phenotypes, but not on HCC cell lines with mesenchymal phenotypes. Finally, a rescue experiment confirmed that let-7a affected the sensitivity of HCC cell lines to cetuximab by interacting with STAT3. There is a functional link between let-7a and STAT3 in enhancing the sensitivity of HCC cells with an epithelial phenotype to cetuximab. Our results provide novel insight into new methodologies for combating HCC drug resistance.