Hsa_circ_0002103 promotes progression of colorectal cancer via miR-193a-3p/CCND1 axis

Colorectal cancer (CRC) is one of the leading causes of cancer-related deaths, with poor prognosis due to late diagnosis. Circular RNAs (circRNAs) are emerging as important regulators in cancer progression. This study investigates the role of hsa_circ_0002103/miR-193a-3p/CCND1 axis in CRC cells, focusing on its regulation of tumor growth, metastasis, and immune evasion. Bioinformatics analysis identified differentially expressed circRNAs (DECs) and miRNAs (DEMs) and constructed the circRNA-miRNA-target gene network in CRC. The hsa_circ_0002103/miR-193a-3p/CCND1 axis was validated using RIP, RNA pulldown, and dual-luciferase assays. Functional experiments assessed the effects on CRC cell proliferation, migration, invasion, and immune evasion. The expression of hsa_circ_0002103 was significantly increased in CRC cells, where it acted as a sponge for miR-193a-3p and promoted CCND1 expression. Hsa_circ_0002103 silencing inhibited the proliferation, migration, and invasion of CRC cells. These effects were reversed by the inhibition of miR-193a-3p. Furthermore, the axis modulated key immune-related factors by reducing the secretion of TNF-α and IFN-γ and upregulating PD-L1. The hsa_circ_0002103/miR-193a-3p/CCND1 axis promotes CRC cell progression and modulates key mediators of immune evasion, representing a potential therapeutic target.