Abstract
AIM: To investigate the impact of hsa_circ_0007482 on the proliferation and apoptosis of human pterygium fibroblasts (HPFs) and its correlation with the severity grades of pterygium. METHODS: Pterygium and normal conjunctival tissues were collected from the superior area of the same patient's eye (n=33). The correlation between pterygium severity and hsa_circ_0007482 expression using quantitative reverse-transcription polymerase chain reaction (RT-qPCR) were analyzed. Three distinct siRNA sequences targeting hsa_circ_0007482, along with a negative control sequence, were transfected into HPFs. Cell proliferation was assessed using the cell counting kit-8. Expression levels of Ki67, proliferating cell nuclear antigen (PCNA), Cyclin D1, Bax, B-cell lymphoma-2 (Bcl-2), and Caspase-3 were measured via RT-qPCR. Immunofluorescence staining was employed to detect Ki67 and vimentin expressions. Apoptosis was evaluated using flow cytometry. RESULTS: Hsa_circ_0007482 expression was significantly higher in pterygium tissues compared to normal conjunctival tissues (P<0.001). Positive correlations were observed between hsa_circ_0007482 expression and pterygium severity, thickness, and vascular density. Knockdown of hsa_circ_0007482 inhibited cell proliferation, reducing the mRNA expression of Ki67, PCNA, and Cyclin D1 in HPFs. Hsa_circ_0007482 knockdown induced apoptosis, increasing mRNA expression levels of Bax and Caspase-3, while decreasing Bcl-2 expression in HPFs. Additionally, hsa_circ_0007482 knockdown attenuated vimentin expression in HPFs. CONCLUSION: The downregulation of hsa_circ_0007482 effectively hampers cell proliferation and triggers apoptosis in HPFs. There are discernible positive correlations detected between the expression of hsa_circ_0007482 and the severity of pterygium.