Objective: To investigate the expression levels of LINC00342 in gastric cancer (GC) tissues and cells and the pathways mediating its effects on biological behaviors of GC cells.
Methods: Bioinformatic analysis was performed to identify the lncRNAs and their downstream miRNAs involved in regulation of biological behaviors of GC cells. qRT-PCR was used to analyze the differential expression of LINC00342 and miR-596 in GC cell lines, human gastric mucosal cells, and GC and adjacent tissues. In human GC MGC-803 and MGC-823 cells, the effects of LINC00342 overexpression, miR-596 overexpression, LINC00342 knockdown, or miR-596 knockdown on cell proliferation, migration, invasion and cell cycle changes were examined using Edu assay, CCK-8 assay, wound healing assay, Transwell assay, and flow cytometry. The regulatory interaction between LINC00342 and miR-596 was investigated using a dual-luciferase reporter assay.
Results: Informatic analysis identified LINC00342 as the candidate lncRNA regulating biological behaviors of GC cells, with miR-596 as its downstream miRNA. LINC00342 expression levels were significantly higher while miR-596 expression levels were lower in GC tissues and cell lines than in the paired adjacent tissues and human gastric mucosal cell lines (all P<0.05). In MGC-803 and MGC-823 cells, overexpression of LINC00342 significantly enhanced cell proliferation (P<0.05), migration (P<0.01), and invasion (P<0.001) and reduced the percentage of G0/G1 phase cells (P<0.01), while knocking down LINC00342 significantly suppressed cell proliferation (P<0.05), migration (P<0.01), and invasion (P<0.001) and increased G0/G1 phase cell percentage (P<0.01). Modulation of miR-596 expression levels produced the opposite effects. Dual-luciferase reporter assay confirmed the specific binding between LINC00342 and miR-596 (P=0.0067).
Conclusion: In GC cells, LINC00342 regulates cell proliferation, migration, and invasion by targeting miR-596.
目的: 研究LINC00342在胃癌组织、细胞中的表达水平及影响胃癌细胞生物学功能的具体通路。
方法: 运用生物信息学技术，通过GEO数据库及相关预测软件，进行相关筛选及文献查询后，确定所研究的LncRNA及其下游所调控的miRNA；采用qRT-PCR检测LINC00342、miR-596在胃癌细胞系及人胃黏膜细胞中、胃癌组织及相应癌旁组织中的表达差异；细胞生物学功能上，过表达胃癌BGC-823细胞系中的LINC00342，将其分为pcDNA-LINC00342组和pcDNA组；过表达胃癌MGC-803细胞系中的miR-596，将其分为miR-596-mimic组及mimic-NC组；敲低胃癌MGC-803细胞系中LINC00342的表达，将其分为siLINC00342组及si-NC组、敲低胃癌BGC-823细胞系中miR-596的表达，将其分为miR-596-inhibitor组及inhibitor-NC组；分别进行CCK-8、Edu细胞增殖实验、划痕实验、Transwell细胞侵袭实验、细胞周期实验以验证LINC00342及miR-596对胃癌细胞功能的影响；双荧光素酶标记实验验证LINC00342与miR-596的靶向调控关系。
结果: 通过生物信息学技术及相关软件预测分析，确定所研究LncRNA为LINC00342，预测其下游调控的miRNA为miR-596；LINC00342在胃癌组织中表达高于癌旁组织（P<0.05）；在人胃癌细胞系中表达高于人胃黏膜细胞系（P<0.05），miR-596则相反（P<0.05）；在胃癌细胞中，LINC00342的过表达能促进胃癌细胞的增殖（P<0.05）、迁移（P<0.01）和侵袭（P<0.001），且减少处于G0/G1期的细胞比率（P<0.01）；LINC00342敲低后，胃癌细胞的增殖（P<0.05）、迁移（P<0.01）和侵袭（P<0.001）则受抑制，增加处于G0/G1期的细胞比率（P<0.01）；miR-596则发挥着相反的作用。LINC00342和miR-596能特异性结合（P=0.0067）。
结论: 在胃癌细胞中，LINC00342通过调控miR-596，促进胃癌细胞的增殖、迁移和侵袭。
Keywords: LINC00342; MGC-803 and BGC-823 cell lines; bioinformatics; long-stranded non-coding ribonucleic acid; miR-596.