LincRNA-p21 Enhances the Sensitivity of Radiotherapy for Gastric Cancer by Targeting the β-catenin Signaling Pathway

Long noncoding RNAs (lncRNAs) are a large and diverse class of transcribed RNA molecules with a length of more than 200 nucleotides that modulate the gene expression at the posttranscriptional or transcriptional level. LncRNAs played crucial roles in many biological processes, such as cell proliferation, metastasis, and migraton. In this study, we evaluated the role of lincRNA-p21 in the gastric cancer (GC). We demonstrated that the expression level of lincRNA-p21 was downregulated in the GC tissues and cell lines. Moreover, ectopic expression of lincRNA-p21 suppressed the GC cell growth, cell cycle, and migration. Furthermore, we demonstrated that the X-ray increased the expression level of lincRNA-p21 in both the HCG-27 and SGC7901 cells and elevated expression of lincRNA-p21 increased the radiotherapy sensitivity of the GC cell. In addition, we showed that ectopic expression of lincRNA-p21 suppressed the β-catenin and c-myc expression. Overexpression of lincRNA-p21 inhibited the GC cell proliferation and increased the radiosensitivity of GC cells by regulating the β-catenin signaling pathway. These data suggested that lincRNA-p21 acted as a tumor suppressor gene in the development of GC.