目的 探讨miR-494在乳腺癌组织和乳腺癌细胞系中的表达及其与乳腺癌临床分期、转移和预后的关系.方法 实时荧光定量聚合酶链反应(qRT-PCR)检测5种乳腺癌细胞系MDA-MB-231、MDA-MB-453、HCC-1937、MDA-MB-468、MCF-7和乳腺上皮细胞系HBL-100中miR-494的表达水平;收集54对乳腺癌组织和癌旁组织,用qRT-PCR法检测其miR-494的表达水平,并分析其与乳腺癌临床分期、转移和预后的关系.结果 qRT-PCR检测结果显示,与正常乳腺上皮细胞HBL-100相比,MDA-MB-231、MDA-MB-453、HCC-1937、MDA-MB-468、MCF-7乳腺癌细胞系中miR-494的表达水平均明显降低(t分别为212.9、37.73、27.53、10.61、19.46,P均<0.05).此外,miR-494在乳腺癌组织中的表达水平亦明显低于癌旁组织(t=5.80,P<0.01),且与临床分期(x2=17.41,P<0.05)、组织病理分级(x2=5.33,P<0.05)、C-erbB-2表达情况(x2=9.83,P<0.05)、Ki-67阳性细胞百分比(x2=6.13,P<0.05)有关.结论 miR-494在乳腺癌组织和乳腺癌细胞系中低表达,且与乳腺癌临床分期、转移和预后关系密切,可成为乳腺癌辅助诊断和预后判断的分子标志.
Objective To investigate the expression levels of miR-494 in breast cancer tissues and cell lines,and its correlations with the clinical stages,metastasis and prognosis of breast cancer.Methods The expression levels of miR--494 in 5 breast cancer cell lines,including MDA-MB-231,MDA-MB-453,HCC-1937,MDA-MB-468 and MCF-7,and normal breast cell line HBL-100,were detected by quantitative real-time polymerase chain reaction (qRT-PCR).The breast cancer tissues and normal adjacent tissues from 54 patients with breast cancer were collected,and their expression levels of miR-494 were determined by qRT-PCR.Then,the correlations of miR-494 levels with clinical stages,metastasis and prognosis of breast cancer were analyzed.Results The expression levels of miR-494 in MDA-MB-231,MDA-MB-453,HCC-1937,MDA-MB-468 and MCF-7 cells were significantly lower than that in HBL-100 cells (t =212.9,37.73,27.53,10.61 and 19.46,respectively,and all P <0.05).The expression levels of miR-494 in breast cancer tissues were also significantly lower than that in normal adjacent tissues (t =5.80,P < 0.01).Moreover,the expression of miR-494 was significantly related to the clinical stage (x2 =17.41,P <0.05),tumor grade (x2 =5.33,P <0.05),C-erbB-2 expression (x2 =9.83,P < 0.05) and the percentage of Ki-67 positive cells ((2 =6.13,P < 0.05) of breast cancer.Conclusion The expression levels of miR-494 are significantly dowrregulated in breast cancer tissues and cell lines,and related to the clinical stage,metastasis and prognosis of breast cancer,indicating that miR-494 may serve as a new biomarker for the diagnosis and prognosis of breast cancer.