长链非编码RNA LINC01001在乳腺癌中的表达及其对MCF-7细胞增殖的影响

Expression of lncRNA LINC01001 in breast cancer and its effect on proliferation of MCF-7 cells

目的:探讨长链非编码RNA LINC01001在乳腺癌组织中的表达及其对乳腺癌MCF-7细胞增殖能力的影响。方法:筛选2016年3月至2017年6月于湖北医药学院附属人民医院甲状腺乳腺外科行手术切除的乳腺癌患者癌及癌旁组织12例,qRTPCR检测乳腺癌组织及癌旁组织LINC01001的相对表达量;通过重组质粒在人乳腺癌MCF-7细胞中过表达LINC01001,采用流式细胞术和MTT法检测过表达LINC01001后MCF-7细胞周期分布和增殖能力变化。qRT-PCR检测miR-485-5p和CDKN1A mRNA的表达变化,Western blotting检测CDKN1A、CDK4、CDK6和Cyclin D1蛋白表达变化。结果:LINC01001在乳腺癌组织中表达水平低于对应的癌旁组织(P<0.01)。LINC01001重组质粒转染MCF-7细胞后可显著抑制细胞周期进展(P<0.05),抑制细胞的增殖能力(P<0.05)。过表达LINC01001后,MCF-7细胞的miR-485-5p的表达水平降低(P<0.01),CDKN1A mRNA表达水平升高(P<0.01);可促进CDKN1A蛋白的表达和抑制CDK4、CDK6和Cyclin D1蛋白的表达。结论:LINC01001在乳腺癌组织中表达降低,其可能通过下调miR-485-5p的表达上调CDKN1A的表达来抑制乳腺癌MCF-7细胞的增殖能力,为lncRNA的临床应用提供实验基础。

Objective： To investigate the expression of long non-coding RNA LINC01001 in breast cancer tissues and its effect on the proliferation of breast cancer MCF-7 cells. Methods： The expression levels of lncRNA LINC01001 were analyzed in 12 cases of cancer and para-cancer tissues from breast cancer patients, who underwent surgical resection in Affiliated People ＇s Hospital of Hubei University of Medicine from March 2016 to June 2017. The plasmid over-expressing LINC01001 was transfected into human breast cancer MCF-7 cells. The cell cycle distribution and proliferation ability of MCF-7 cells were detected by flow cytometry and MTT assay, respectively. The mRNA expressions of miR-485-5p and CDKN1A mRNA were detected by qRT-PCR, and the protein expressions of CDKN1A, CDK4, CDK6 and Cyclin D1 were detected by Western blotting. Results： The expression level of lncRNA LINC01001 in breast cancer tissues was lower than that in para-cancer tissues（P〈0.01）. LINC01001 recombinant plasmid transfection significantly inhibited cell cycle progression（P〈0.05） and cell proliferation（P〈0.05） of MCF-7 cells. qRT-PCR showed that the expression level of miR-485-5p was decreased（P〈0.01） and the expression level of CDKN1A mRNA was increased（P〈0.01） after over-expressing LINC01001. Western blot results confirmed that over-expression of LINC01001 could promote the expression of CDKN1A protein, but decrease the expressions of CDK4, CDK6 and Cyclin D1 proteins. Conclusion： The expression of LINC01001 in breast cancer tissues was decreased. LINC01001 may down-regulate the expression of miR-485-5p to up-regulate the expression of CDKN1A, and further to inhibit the proliferation of breast cancer MCF-7 cells, providing experimental basis for the clinical application of lncRNA.