Circular RNA circ-SMAD7 promoted glioma cell proliferation and metastasis by upregulating PCNA.

OBJECTIVE: Recent studies have discovered a class of circular RNAs (circRNAs), which are dysregulated in various tumors and participate in the regulation of tumor progression. In our research, we aim to research the function of circ-SMAD7 in the progression of glioma. PATIENTS AND METHODS: Circ-SMAD7 expression was detected by quantitative Real Time Polymerase Chain Reaction (qRT-PCR) in glioma tissue patients. Pearson's Chi-square test was used to determine the association of circ-SMAD7 expression with several clinicopathological factors. Besides, cell proliferation assay, cell cycle assay, transwell assay, and Matrigel assay were conducted to detect the function of circ-SMAD7 in glioma. In addition, the interaction between circ-SMAD7 and proliferating cell nuclear antigen (PCNA) in glioma was studied by performing qRT-PCR and Western blot assay. RESULTS: Circ-SMAD7 expression was observed in glioma tissues when compared with adjacent samples. The expression of circ-SMAD7 was associated with patients' WHO stage and KPS score. Cell proliferation was inhibited and cell cycle was regulated after circ-SMAD7 was downregulated in glioma cells. Besides, cell migration and invasion were inhibited after circ-SMAD7 was downregulated in glioma cells. In addition, the mRNA and protein expression of PCNA was repressed after circ-SMAD7 was knocked down in glioma cells. Furthermore, PCNA expression level positively correlated to circ-SMAD7 expression level in glioma samples. CONCLUSIONS: Our study suggests that circ-SMAD7 promotes proliferation and metastasis of glioma via upregulating PCNA. Circ-SMAD7/ PCNA might be a novel therapeutic strategy in glioma. [ABSTRACT FROM AUTHOR]