Hypomethylation of the lncRNA SOX21-AS1 has clinical prognostic value in cervical cancer.

Objective: Cervical cancer seriously affects women's health. The function of methylated alterations in the long non-coding RNAs (lncRNAs) promote the progression and metastasis of cancer. Our study aims to identify the functional effects of lncRNA methylation in cervical carcinogenesis.

Methods: Genome-wide DNA methylation of 6 samples was assessed using the Illumina Infinium MethylationEPIC BeadChip. RNA sequencing (RNA-seq) data and survival follow-up time of 307 samples from The Cancer Genome Atlas (TCGA) dataset were enrolled in this study. The statistical analysis and graphical work were mainly realized by R language.

Results: Methylation map identified 3962 hypermethylated CpG sites and 4484 hypomethylated CpG sites in cervical cancer (|Δβ| ≥ 0.20). Bioinformatic analysis of the lncRNA expression identified 363 upregulated and 664 downregulated lncRNAs with log2 (fold change) ≥ 1.00 in squamous cervical carcinoma (SCC) samples. Weighted gene co-expression network analysis (WGCNA) and Venn diagram revealed that lncRNA MAGI2 antisense RNA 3 (lncRNA MAGI2-AS3), lncRNA WT1 antisense RNA (lncRNA WT1-AS) and lncRNA SOX21 antisense divergent transcript 1 (lncRNA SOX21-AS1) were important methylation changed lncRNAs. Kaplan-Meier survival curves showed only lncRNA SOX21-AS1 had clinical prognostic value in cervical cancer. Gene set enrichment analysis (GSEA) suggest that lncRNA SOX21-AS1 involve in the multiple cellular processes and might significantly suppress cervical tumorigenesis.

Conclusions: These insights into the functional role of lncRNA SOX21-AS1 DNA methylome alterations in cervical cancer might promote clinically new applicable in diagnosis and prognosis.