下调lncRNA MCF2L-AS1靶向miR-33b-5p抑制胃癌细胞增殖、迁移、侵袭并促进凋亡

摘要 目的：探讨lncRNA MCF2L-AS1对胃癌细胞恶性生物学行为的影响及分子机制。方法：选取45例胃癌患者的癌组织及癌旁正常组织，或培养胃黏膜上皮细胞GES-1、胃癌细胞HGC-27，采用RT-qPCR检测MCF2L-AS1和miR-33b-5p的表达水平。采用双荧光素酶报告实验检测MCF2L-AS1和miR-33b-5p的靶向关系。将HGC-27细胞分为si-NC组、si-MCF2L-AS1组、mimic NC组、miR-33b-5p mimic组、si-MCF2L-AS1+inhibitor NC组、si-MCF2L-AS1+miR-33b-5p inhibitor组，分别转染si-NC、si-MCF2L-AS1、mimic NC、miR-33b-5p mimic或共转染si-MCF2L-AS1+inhibitor NC、si-MCF2L-AS1+miR-33b-5p inhibitor。采用MTT实验检测细胞增殖情况，流式细胞术检测细胞凋亡率，克隆形成实验检测细胞克隆形成数，Transwell实验检测迁移和侵袭细胞数。结果：与癌旁正常组织或GES-1细胞相比，胃癌组织或HGC-27细胞中MCF2L-AS1表达水平升高、miR-33b-5p表达水平降低，差异均有统计学意义（P<0.05）。MCF2L-AS1可靶向调控miR-33b-5p。下调MCF2L-AS1或过表达miR-33b-5p，miR-33b-5p表达水平升高，HGC-27细胞凋亡率升高，但细胞增殖、克隆形成数、迁移和侵袭数均减少，差异均有统计学意义（P<0.05）。抑制miR-33b-5p可减弱下调MCF2L-AS1对HGC-27细胞的生物学作用。结论：下调MCF2L-AS1通过上调miR-33b-5p抑制胃癌细胞增殖、迁移、侵袭并促进凋亡；MCF2L-AS1通过靶向调控miR-33b-5p表达进而参与胃癌细胞的恶性生物学行为。

Downregulation of lncRNA MCF2L-AS1 Targeting miR-33b-5p Inhibits Gastric Cancer Cell Proliferation, Migration and Invasion, and Promotes Apoptosis

ABSTRACT Objective: To investigate the effect of lncRNA MCF2L-AS1 on the malignant biological behavior of gastric cancer cells and its molecular mechanism. Methods: The expression levels of MCF2L-AS1 and miR-33b-5p in cancer tissues and paracancerous tissues of 45 patients with gastric cancer, or in cultured gastric mucosal epithelial cells GES-1 and gastric cancer cells HGC-27 were detected by RT-qPCR. The targeting relationship between MCF2L-AS1 and miR-33b-5p was detected by dual luciferase reporter assay. HGC-27 cells were divided into si-NC group, si-MCF2L-AS1 group, mimic NC group, miR-33b-5p mimic group, si-MCF2L-AS1+inhibitor NC group, si-MCF2L-AS1+miR-33b-5p inhibitor group, respectively transfected with si-NC, si-MCF2L-AS1, mimic NC, miR-33b-5p mimic or co-transfected with si-MCF2L-AS1+inhibitor NC, si-MCF2L-AS1+miR-33b-5p inhibitor. MTT assay was used to detect the cell proliferation, flow cytometry was used to detect the apoptosis rate, clone formation assay was used to detect the number of cell clones, and Transwell assay was used to detect the number of migration and invasion cells. Results: The expression level of MCF2L-AS1 was increased and the expression level of miR-33b-5p was decreased in gastric cancer tissues or HGC-27 cells compared with paracancerous tissues or GES-1 cells (P<0.05). MCF2L-AS1 can target and regulate miR-33b-5p. Downregulation of MCF2L-AS1 or overexpression of miR-33b-5p could increase the expression level of miR-33b-5p, increase the apoptosis rate but decrease the cell proliferation, clone formation number, migration and invasion number of HGC-27 cells, with statistical significance (P<0.05). Inhibition of miR-33b-5p could attenuate the biological effect of downregulating MCF2L-AS1 on HGC-27 cells. Conclusion: Downregulation of MCF2L-AS1 inhibits the proliferation, migration and invasion and promotes apoptosis of gastric cancer cells by upregulating miR-33b-5p; MCF2L-AS1 participates in the malignant biological behavior of gastric cancer cells by targeting the expression of miR-33b-5p.