Supplementary Material for: lncRNA DLG1-AS1 Promotes Cell Proliferation by Competitively Binding with miR-107 and Up-Regulating ZHX1 Expression in Cervical Cancer

Background/Aims: Recent studies have revealed that long non-coding RNAs (lncRNAs) are involved in the occurrence and development of various tumors, thereby attracting increasing attention from researchers. The important biological functions of lncRNAs have been recognized gradually, but their mechanism in cervical cancer remains unclear. Methods: Differentially expressed lncRNAs in cervical cancer and para-carcinoma tissues were identified by screening using an lncRNA array, and candidate lncRNAs were verified by quantitative real-time PCR. A series of bioinformatics and molecular biological methods were adopted to investigate the interactions among lncRNAs, microRNAs (miRNAs), and miRNA target genes in cervical cancer. Cell viability was measured using a Cell Counting Kit-8 assay. Results: DLG1-AS1 was the most significantly up-regulated lncRNA in cervical cancer tissues, and it was confirmed that cervical cancer patients with high DLG1-AS1 expression had a poor prognosis. Down-regulation of DLG1-AS1 expression suppressed the proliferation of cervical cancer cells. Further investigation revealed that DLG1-AS1 eliminated the inhibition of miR-107 on the expression of its target gene ZHX1 by competitively binding to miR-107. Moreover, rescue assays proved that the effect of DLG1-AS1 on the proliferation of cervical cancer cells was dependent on miR-107. Conclusion: DLG1-AS1/miR-107/ZHX1 can form a competitive endogenous RNA network that regulates the proliferation of cervical cancer cells, resulting in tumor progression.

背景与目的：近期研究表明，长链非编码RNA（long non-coding RNAs，lncRNAs）参与多种肿瘤的发生与发展进程，因此受到研究者的日益关注。长链非编码RNA的重要生物学功能已逐渐得到学界认可，但其在宫颈癌中的作用机制仍未明确。
方法：通过长链非编码RNA芯片（lncRNA array）筛选鉴定宫颈癌组织与癌旁组织中的差异表达长链非编码RNA，并通过实时定量聚合酶链反应（quantitative real-time PCR）验证候选长链非编码RNA。采用一系列生物信息学及分子生物学方法，探究宫颈癌中长链非编码RNA、微小RNA（microRNAs，miRNAs）及其靶基因之间的相互调控关系。采用细胞计数试剂盒-8（Cell Counting Kit-8，CCK-8）检测法测定细胞活力。
结果：DLG1-AS1是宫颈癌组织中上调幅度最显著的长链非编码RNA，且证实高表达DLG1-AS1的宫颈癌患者预后不良。下调DLG1-AS1的表达可显著抑制宫颈癌细胞的增殖能力。进一步研究显示，DLG1-AS1可通过竞争性结合微小RNA-107（miR-107），解除其对靶基因ZHX1表达的抑制作用。此外，挽救实验证实，DLG1-AS1对宫颈癌细胞增殖的调控作用依赖于miR-107。
结论：DLG1-AS1/miR-107/ZHX1可形成竞争性内源RNA（competing endogenous RNA，ceRNA）调控网络，通过调控宫颈癌细胞的增殖促进肿瘤进展。