MiR-503 regulates cisplatin resistance of human gastric cancer cell lines by targeting IGF1R and BCL2
MiR-503 regulates cisplatin resistance of human gastric cancer cell lines by targeting IGF1R and BCL2
复制标题
MiR-503 通过靶向 IGF1R 和 BCL2 调节人胃癌细胞系的顺铂耐药性。
DOI：
10.3760/cma.j.issn.0366-6999.20140318
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发表时间：
2014-06-20
影响因子：
6.1
通讯作者：
Liu Ping
中科院分区：
文献类型：
--
作者：
Wang Tongshan;Ge Gaoxia;Liu Ping
背景研究表明，胃癌细胞的耐药性可通过microRNAs（miRNAs）的异常表达来调控。我们研究了miR-503在人胃癌细胞系顺铂耐药发展中的作用。使用MTT（3-（4，5-二甲基噻唑-2-基）-2，5-二苯基四唑溴化物）和克隆形成测定来检查与miRNA的上调或下调相关的癌细胞的细胞活力和耐药性表型的变化。使用双荧光素酶活性测定来验证miR-503的靶基因。结果miR-503在胃癌组织和胃癌细胞株中表达明显下调，与对照组相比差异有统计学意义（P < 0. 05）。此外，与亲本SGC 7901细胞系相比，顺铂（DDP）耐药胃癌细胞系SGC 7901/DDP中miR-503的下调与胰岛素样生长因子-1受体（IGF 1 R）和B细胞淋巴瘤2（BCL 2）表达的上调同时发生。体外药物敏感性实验显示miR-503过表达可使胃癌细胞对顺铂敏感。SGC 7901/DDP细胞中由IGF 1 R和BCL 2 3 '非翻译区驱动的报告基因的荧光素酶活性表明IGF 1 R和BCL 2都是miR-503的直接靶基因。结论hsa-miR-503通过靶向IGF 1 R和BCL-2调节胃癌细胞顺铂耐药，并可能通过抑制胃癌细胞的增殖和凋亡来抑制胃癌细胞的顺铂耐药。
Background Studies have shown that the drug resistance of gastric cancer cells can be modulated by abnormal expression of microRNAs (miRNAs). We investigated the role of miR-503 in the development of cisplatin resistance in human gastric cancer cell lines.Methods MiR-503 expression was measured by quantitative real-time PCR. MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) and clonogenic assays were used to examine changes in cell viability and the drug resistance phenotype of cancer cells associated with upregulation or downregulation of the miRNA. A dual-luciferase activity assay was used to verify target genes of miR-503. Imnnunohistochemistry, Western blotting analysis, and a flow cytometric apoptosis assay were used to elucidate the mechanism by which miR-503 modulates drug resistance in cancer cells.Results MiR-503 was significantly downregulated in gastric cancer tissues and several gastric cancer cell lines. Additionally, downregulation of miR-503 in the cisplatin (DDP)-resistant gastric cancer cell line SGC7901/DDP was concurrent with the upregulation of insulin-like growth factor-1 receptor (IGF1R) and B-cell lymphoma 2 (BCL2) expression compared with the parental SGC7901 cell line. An in vitro drug sensitivity assay showed that overexpression of miR-503 sensitized SGC7901/DDP cells to cisplatin. The luciferase activity of reporters driven by IGF1R and BCL2 3'-untranslated regions in SGC7901/DDP cells suggested that IGF1R and BCL2 were both direct target genes of miR-503. Enforced miR-503 expression in SGC7901/DDP cells reduced expression of the target proteins, inhibited proliferation, and sensitized the cells to DDP-induced apoptosis.Conclusion Our findings suggest that hsa-miR-503 modulates cisplatin resistance of human gastric cancer cells at least in part by targeting IGF1R and BCL2.