LncRNA MIR4435-2HG predicts poor prognosis in patients with colorectal cancer

Background: LncRNA MIR4435-2HG is observed in a variety of cancers, while its role in colorectal cancer is unknown. We aimed to demonstrate the relationship between MIR4435-2HG and colorectal cancer based on The Cancer Genome Atlas (TCGA) database. Materials and Methods: Patients with colorectal cancer were collected from TCGA. We compared the expression of MIR4435-2HG in colorectal cancer and normal tissues with Wilcoxon rank sum test, and logistic regression was used to evaluate the relationship between MIR4435-2HG and clinicopathological characters. Moreover, Kaplan-Meier and Cox regression was performed to evaluate the correlation between MIR4435-2HG and survival rate. Gene set enrichment analysis (GSEA) was also conducted to annotate biological function of MIR4435-2HG. Results: MIR4435-2HG level was elevated in colorectal cancer tissues. Increased level of MIR4435-2HG was significantly correlated with TNM stage (OR = 1.66 for T1/T2 vs. T3/T4; OR = 1.68 for N0 vs. N1/N2), stage (OR = 1.66 for stage 1/2 vs. stage 3/4), and carcinoembryonic antigen level before treatment (OR = 1.70 for <5 vs. >= 5) (all P-value <0.05). High MIR4435-2HG expression had a poorer progression-free survival (p = 0.048), and overall survival (OS) (P = 0.028), which were validated in the GSE92921 and GSE29621 datasets. MIR4435-2HG expression (P = 0.040, HR = 1.955 (95% CI [1.031-3.710])) was independently correlated with OS. GSEA demonstrated that the P38/MAPK pathway, the VEGF pathway, the cell adhesion molecules cams, the NOD-like receptor signaling pathway, the cell surface interactions at the vascular wall, and integrin cell surface interactions were differentially enriched in MIR4435-2HG high expression phenotype. Conclusions: Increased MIR4435-2HG might be a potential biomarker for the diagnosis and prognosis of colorectal cancer. Moreover, MIR4435-2HG might participate in the development of colorectal cancer via the P38/MAPK and VEGF pathway.