circRNA THBS1 silencing inhibits the malignant biological behavior of cervical cancer cells via the regulation of miR-543/HMGB2 axis

Circular RNA (circRNA) THBS1 has been shown to exist as an oncogene in non-small-cell lung cancer, but its role in cervical cancer is still unclear. Our experiment aimed to uncover the functions and specific mechanism of circRNA THBS1 in cervical cancer cells. Levels of circRNA THBS1 and miR-543 in cervical cancer tissues and cell lines were assessed by RT-qPCR. starBase and dual luciferase reporter gene assay were applied for investigating the correlation between miR-543 and circRNA THBS1/HMGB2. Cell proliferation and apoptosis were evaluated by MTT and flow cytometry, respectively. Furthermore, the levels of HMGB2, E-cadherin, and N-cadherin in HeLa cells were determined by RT-qPCR and western blot analysis. Our data revealed that circRNA THBS1 was significantly upregulated and miR-543 was low expressed in cervical cancer tissues and cell lines. circRNA THBS1 interacted with miR-543 and negatively regulated miR-543 expression in HeLa cells. Silencing of circRNA THBS1 remarkably suppressed HeLa cells’ viability, accelerated cells’ apoptosis, and inhibited the EMT of HeLa cells, while these changes were reversed by miR-543 inhibitor. Moreover, miR-543 affected HeLa cells by targeting HMGB2. In conclusion, circRNA THBS1 silencing inhibited the malignant biological behaviors of cervical cancer cells via the regulation of miR-543/HMGB2 axis.