Circular RNAs (
circRNAs/circs) have gained attention as a class of potential
biomarkers for the early detection of multiple
cancers. However, the functions and mechanisms of
circRNAs in the
oncogenesis of human
colorectal cancer (CRC) remain to be elucidated. The present study aimed to investigate the roles of hsa_circ_0000523 and its parental gene
methyltransferase-like 3 (METTL3) in regulating cell proliferation, apoptosis and invasion in the HCT116 human CRC cell line. To uncover the regulated function of hsa_circ_0000523 in HCT116 cells, a dual-
luciferase reporter assay, flow cytometry, reverse transcription-quantitative PCR, Cell Counting Kit-8 assay, cell invasion and western blot assay were used. In HCT116 cells, hsa_circ_0000523 indirectly regulated METTL3 expression by suppressing the transcription of
microRNA (miR)-let-7b. The expression of METTL3 promoted cell proliferation and suppressed apoptosis. In the present study, it was found that miR-let-7b promoted cell viability and inhibited apoptosis and invasion, while circ_0000523 exerted the opposite effects. Higher levels of METTL3 expression were associated with more aggressive
tumor invasion. The present results suggest that
circRNAs and METTL3 may be applied for highly sensitive diagnosis of CRC and for predicting prognosis in patients who have undergone
therapy.