miR-133a-3p Functions as a Tumor Suppressor in Colorectal Cancer by Targeting PFKFB3

Background Recent studies reveal that PFKFB3 plays an important role in tumorigenesis and tumor progression. Our study aims to identify an novel microRNA which can suppress the expression of PFKFB3 and to provide a potential target for tumor therapy. Methods Bioinformatics methods were implemented to explore the expression and clinical significance of PFKFB3 and miR-133a-3p in colorectal cancer (CRC). qRT-PCR was performed to detect PFKFB3, miR-133a-3p, KI67 and MMP9 mRNA expression, while western bot was carried out for the detection of protein expression of PFKFB3, miR-133a-3p, KI67 and MMP9. Bioinformatics analysis was used to predict the binding sites of miR-133a-3p on PFKFB3 3’UTR, while dual-luciferase assay was conducted to validate their binding relationship. CCK-8 assay, KI67 detection, Transwell assay and MMP9 detection were employed to measure CRC cell proliferative and invasive abilities. Results PFKFB3 expression is up-regulated in colorectal cancer, and is significantly associated with poor prognosis. Silencing PFKFB3 could inhibit the proliferation and invasion of colorectal cancer cells. miR-133a-3p is down regulated in colorectal cancer, which has diagnostic value for colorectal cancer. Dual luciferase assay confirmed that PFKFB3 was the direct acting site of miR-133a-3p. Overexpression of miR-133a-3p could significantly reduce the expression of PFKFB3 and inhibit the effect of PFKFB3 on the proliferation and invasion of colorectal cancer cells. Conclusions Our study suggested that miR-133a-3p functions as a novel tumor suppressor in colorectal cancer by targeting PFKFB3.