目的：探讨lncRNASNHG15靶向miR-153对乳腺癌细胞增殖和凋亡的影响及其凋亡机制。方法: 用实时荧光定量 PCR（qPCR）检测乳腺癌细胞系MDA-MB-231、BT-549 和 MCF-7中SNHG15表达水平。将MDA-MB-231 细胞分为对照（Ctrl） 组、si-NC组、si-SNHG15组、si-SNHG15+anti-NC组及si-SNHG15+anti-miR-153组， 用MTT法及流式细胞术分别检测细胞的增殖 活力和凋亡率。用双荧光素酶报告基因实验验证SNHG15和miR-153的靶向关系。用线粒体膜电位荧光探针（JC-1）染色法检测 细胞线粒体膜电位， 用Western blotting检测线粒体途径凋亡相关蛋白Bcl-2、Bax、caspase3、cleaved caspase3（c-caspase3）和Cyt-C 的表达水平。结果:SNHG15在3种乳腺癌细胞中的表达水平均明显高于人正常乳腺上皮细胞MCF10A（均P<0.01）。SNHG15与 miR-153存在靶向关系。沉默SNHG15后，与对照组比较，si-SNHG15组MDA-MB-231细胞增殖活力明显降低、凋亡率升高、线 粒体膜电位降低（均P<0.01）；细胞中Bcl-2和caspase3表达降低，Bax、c-caspase3和Cyt-C表达升高（均P<0.01）。si-SNHG15与 anti-miR-153共同转染 MDA-MB-231 细胞后，可减弱 si-SNHG15 对细胞增殖、凋亡、线粒体膜电位及 Bcl-2、Bax、caspase3、 c-caspase3和Cyt-C表达的影响（均P<0.01）。结论: lncRNASNHG15可靶向调控miR-153诱导MDA-MB-231细胞凋亡，其机制 可能与调控细胞线粒体途径凋亡有关。

Objective: To investigate the effect of lncRNA SNHG15 targeting miR-153 on cell viability and apoptosis of breast cancer cells and its apoptotic mechanism.Methods:The expression of SNHG15 in breastcancercelllines(MDA-MB-231, BT-549 and MCF-7) were detected by Real-time fluorescent quantitative PCR (qPCR). MDA-MB-231 cells were divided into control (Ctrl) group, si-NC group, si-SNHG15 group, si-SNHG15+anti-NC group and si-SNHG15+anti-miR-153 group. Cell viability and apoptosis rate were detected by MTT and Flow cytometry, respectively. The targeting relationship between SNHG15 and miR-153 was verified by Dual luciferase report gene system. Mitochondrial membrane potential fluorescent probe (JC-1) staining method was used to detect cell mitochondrial membrane potential.The expressions of mitochondrial apoptosis-related proteins (Bcl-2, Bax, caspase3, cleaved caspase3 [c-caspase3] and Cyt-C）were detected by Western blotting. Results:TheexpressionofSNHG15 in breast cancer cells was significantly higher than that in human normal mammary epithelial MCF10A cells (P<0.01). There was a targeting relationship between SNHG15 and miR-153. Compared with the control group, the cell viability and mitochondrial membrane potential of MDA-MB-231 cells in si-SNHG15 group were decreased, while apoptosis rate was increased (all P<0.01); the expressions of Bcl-2 and caspase3 were decreased while expressions of Bax, c-caspase3 and Cyt-C were increased (all P<0.01). However, co-transfection of si-SNHG15 and anti-miR-153 significantly attenuated the effects of si-SNHG15 on cell viability, apoptosis, mitochondrial membrane potential and expressions of Bcl-2, Bax, caspase3, c-caspase3 and Cyt-C (all P<0.01). Conclusion: lncRNA SNHG15 can target miR-153 to induce apoptosis of MDA-MB-231 cells, and the mechanism may be related to the regulation of apoptosis of mitochondrial pathway.

山西省科学技术厅资助项目（No.201803D31088）