Curcumin suppresses colorectal cancer development with epithelial-mesenchymal transition via modulating circular RNA HN1/miR-302a-3p/PIK3R3 axis

Curcumin has been testified to repress the development of multiple tumor cells. Nevertheless, the function of curcumin in colorectal cancer (CRC) is not completely clarified. This research was to explore the influence of curcumin on the development of CRC cells and its mechanism. An examination of circular RNA (circ) HN1, microRNA (miR)-302a-3p and phosphoinositide-3-kinase regulatory subunit 3 (PIK3R3) levels in clinical tissues was performed. Assessments of cell development including proliferation, apoptosis, migration, invasion, as well as epithelial-mesenchymal transition were conducted. The effects of curcumin and circHN1 were verified by in vivo tumor implantation experiments. The interaction of miR-302a-3p with circHN1 or PIK3R3 was analyzed. Curcumin repressed CRC cell development in a concentration-dependent manner. CircHN1 expression was augmented in CRC. Augmentation of circHN1 was able to turn around the repressive effects of curcumin on CRC cells. In vivo experiments indicated that low expression of circHN1 further promoted curcumin-mediated inhibition of CRC tumor growth. MiR-302a-3p was a target of circHN1, and suppression of miR-302a-3p was able to turn around the treatment effect of curcumin on CRC cells. Additionally, PIK3R3 was targeted by miR-302a-3p, and curcumin modulated the malignancy of CRC cells through the circHN1/miR-302a-3p/PIK3R3 pathway.