Fig. 3: Inhibitory effects of the circular structure and protein-coding potential of CCDC7₁₉₋₁₃ on prostate cancer.

A Schematic representation of circular CCDC7₁₉₋₁₃ expression construct. The circular construct includes a specific amino acid sequence (aa) with a translation start site (ATGCAA) and termination site (TAA), along with an IRES element to facilitate translation. A frame shift mutation (ATGAA) is introduced to study the effects of altered CCDC7 expression. The ability of CCDC7₁₉₋₁₃ to form a circular structure is essential for its biological function through protein encoding. B Diagram showing the linearized form of the CCDC7 construct, highlighting the specific amino acid sequence, start site (ATG), and termination site (TAA). C Amplification of CCDC7 (400 bp) and GAPDH (100 bp) in cells transfected with Flag-Vector, Flag-CCDC7₁₉₋₁₃ and Flag-Frame-shift constructs. GAPDH serves as a loading control. D Immunoblotting with anti-Flag antibody confirms the expression of Flag-CCDC7₁₉₋₁₃ in the corresponding transfected cells. E, F Cell viability assay in PC3 and DU145 cells. Cells were transfected with Circular vector, Circular OE, Circular frame shift, Linearized vector, and Linearized OE constructs. G Representative images of colonies formed by PC3 and DU145 cells transfected with the indicated constructs, stained with crystal violet. H The number of colonies formed by PC3 and DU145 cells transfected with different constructs. I Flow cytometry analysis of apoptosis. Representative flow cytometry plots showing Annexin V and PI staining in PC3 and DU145 cells transfected with the indicated constructs. J Histogram analysis of the percentage of apoptotic cells. Statistical significance is indicated: **p < 0.01, ***p < 0.001, ns not significant.