Abstract
The tripartite motif-containing (TRIM) family is a group of proteins that are implicated in a plethora of pathological conditions. TRIM22 has been found to be involved in various cancers; however, the role of TRIM22 in gliomas has not been reported. The present study aimed to evaluate the expression pattern of TRIM22 and its function in gliomas. TRIM22 expressions in glioma tissues and cell lines were measured by RT-PCR and western blot analysis. To knockdown TRIM22 by small hairpin RNAs (shTRIM22), the U118 cells were transfected with pLKO.1-shTRIM22 plasmid or pLKO.1 plasmid. Cell proliferation was measured using CCK-8 assay. Transwell assays were performed to evaluate the migration and invasion. The epithelial-mesenchymal transition (EMT) was assessed by detecting the expressions of E-cadherin, N-cadherin and vimentin with western blot analysis. A xenograft mouse model was established to evaluate the effect of TRIM22 silencing on tumor growth in vivo. The expressions of β-catenin, cyclin D1, and c-Myc were analyzed by western blot analysis. TRIM22 was significantly overexpressed in glioma tissues and cell lines. In vitro studies demonstrated that TRIM22 knockdown inhibited cell proliferation, migration, and invasion. Additionally, TRIM22 silencing increased the expressions of E-cadherin, and decreased the expressions of N-cadherin and vimentin. Nude mouse xenograft assay showed that TRIM22 silencing inhibited tumor growth in vivo. Furthermore, silencing of TRIM22 inhibited the activation of the Wnt/β-catenin pathway. Treatment with LiCl, an activator of the Wnt/β-catenin pathway, attenuated the effects of shTRIM22 on U118 cells. Silencing of TRIM22 inhibited proliferation, migration and invasion, as well as repressing the EMT process in glioma cells. The Wnt/β-catenin pathway was involved in the effect of TRIM22.