MiR-320 inhibits glycometabolism in colorectal cancer by targeting E2F1 gene

Abstract

Objective To study the effect of microRNA-320 (miR-320) targeting E2F1 gene on tumor glycometabolism in colorectal cancer. Methods The miR-320 expression level in colorectal cancer cell lines and cancer tissues was detected using quantitative real-time polymerase chain reaction (qRT-PCR). The binding sites of miR-320 and E2F1 were predicted by bioinformatics. Luciferase assay was used to detect the targeting regulation of miR-320 on E2F1. The relationship between E2F1 and miR-320 was verified in mRNA level and protein level. When the miR-320 in SW480 and LOVO cells was up-regulated and the E2F1 was down-regulated, the changes of glycometabolism in tumor cells were analyzed using glucose/glucose oxidase kit and lactate test kit. Results The qRT-PCR results showed low expressions of miR-320 in colorectal cancer cell lines and cancer tissues (F=42.327, P<0.001; t=4.345, P=0.023). Luciferase assay showed that miR-320 could negatively regulate the expression of E2F1 (t=4.716, P=0.042). The expression levels of E2F1 protein and mRNA (t=4.780, P=0.041; t=5.506, P=0.031) confirmed that miR-320 could interact with E2F1 in LOVO and SW480 cells. Overexpression of miR-320 could reduce the contents of glucose (t=5.262, P=0.034; t=21.079, P=0.002) and lactic acid (t=9.609, P=0.011; t=18.582, P=0.003) in the cellular supernatant in SW480 and LOVO cells. Down-regulating the expression of E2F1 at the same time could enhance the inhibitory effect of miR-320 on glucose (t=5.128, P=0.036; t=5.089, P=0.037) and lactic acid (t=8.573, P=0.013; t=13.364, P=0.006). Conclusion E2F1 is the target gene of miR-320, and miR-320 can regulate the glycometabolism of colorectal cancer cells by targeting E2F1 gene. Key words: Colorectal neoplasms; MicroRNAs; Metabolism; E2F1 transcription factor