Circ_0005785 Silencing Constrains the Functional Properties of Colorectal Cancer Cells Depending on miR-7-5p/DNMT3A Axis.

Abstract

Circular RNAs (circRNAs) closely related to the progression of colorectal cancer (CRC). Nevertheless, the study of circ_0005785 in CRC has not been reported. In this test, we aimed to investigate the mechanisms of circ_0005785 in CRC development. Quantitative real-time polymerase chain reaction (qRT-PCR) and western blot were employed to reveal the expression of genes and proteins. Cell Counting Kit-8 (CCK-8) assay, 5-ethynyl-2'-deoxyuridine (EdU) assay, flow cytometry analysis, transwell assay and tube formation experiment were implemented to examine cell growth, apoptosis, invasion and angiogenesis. The relationships among circ_0005785, miR-7-5p and DNA methyltransferase 3A (DNMT3A) were verified by dual-luciferase reporter assay. Xenograft mouse model was built to evaluate the impacts of circ_0005785 deficiency on CRC growth in vivo. We found thatcirc_0005785was increased in CRC patients and cell lines. Circ_0005785 downregulation retarded cell proliferation, invasion, angiogenesis whereas expedited apoptosis in CRC cells. Mechanistically, circ_0005785 could sponge miR-7-5p and the suppressive treads of circ_0005785 in CRC development was attenuated by miR-7-5p down-regulation. DNMT3A was targeted by miR-7-5p and miR-7-5p overexpression constrained cell malignant behaviors, but the addition of DNMT3A counteracted the effects. Additionally, circ_0005785 inhibition hindered the tumor growth in vivo. In conclusion,circ_0005785aggravated the CRC progression by increasing the level of DNMT3A via adsorbing miR-7-5p.