Co-expression network analysis of long noncoding RNAs (IncRNAs) and cancer genes revealsSFTA1P and CASC2abnormalities in lung squamous cell carcinoma.

Lung squamous cell carcinoma(LSCC) is the most common and aggressive lung tumor with poor clinical outcome. Previously studies showed that deregulation of long noncoding RNAs (lncRNAs) were involved in LSCC. We intended to figure out the role of lncRNAs in the regulation process of cancer-related genes and pathways they are involved. Data of 552 samples, including 501 cancer samples and 51 normal ones, were extracted from The Cancer Genome Atlas (TCGA). Differentially expressed lncRNAs (DEIs) were screened out (FDR<0.05, |logFC|>1) and then followed by GO ontology and KEGG annotation analysis. Oncogenes from COSMIC data set and Tumor suppressor genes (TSGs) from TSGene data set were collected and analyzed by gene Set Enrichment Analysis (GSEA) . The differentially expressed oncogenes and tumor supressor gene (TSGs) were obtained and co-expression analysis was conducted to generate co-expression lncRNA-gene pairs, which can be helpful in figuring out the role of lncRNA in the regulation of oncogenes and tumor suppressor genes. A total of 31 lncRNAs with low expression levels and 37 lncRNAs with high expression levels were screened out and most of them were enriched in pathways such as meiosis, male gamete generation, defensins. Of note, SFTA1P and CASC2 were found to be related with most of the oncogenes and TSGs by co-expression analysis. We suggested SFTA1P and CASC2 played important role in the regulation of both oncogene and TSGs during the carcinogenesis of LSCC and have the potential to be applied in future diagnosis, prognostic process and target therapy of LSCC.