CADM2 inhibits human glioma proliferation, migration and invasion

Malignant glioma is one of the most common malignant tumors in the brain parenchyma with a poor prognosis. Cell adhesion molecules (CADMs) immunoglobulin super family is involved in the maintenance of cell adhesion, polarity and tumor suppression. However, the role and mechanisms of CADM2 in human glioma have yet to be elucidated. Therefore, the present study evaluated the expression level of CADM2 and demonstrated that CADM2 was markedly downregulated in human glioma tissues compared with normal brain tissue and glioma cell lines, and the CADM2 expression level was significantly decreased in high-grade glioma tissues. Overexpression of CADM2 inhibited the proliferation of glioma cell proliferation in vitro and in vivo. CADM2 also inhibited the migration and invasion of U87 and U251 cells. Furthermore, overexpression of CADM2 induced a significant decrease in the expression of G1/S transition key regulators, cyclin D1, cyclin E, cyclin-dependent kinase (CDK)2 and CDK4. Additionally, CADM2 expression was associated with alterations in epithelial-mesenchymal transition (EMT) markers, including E-cadherin and beta-catenin. Taken together, the results of the present study demonstrated that CADM2 inhibits glioma tumorigenesis by regulating the cell cycle and the EMT process, suggesting that CADM2 may be a novel potential therapeutic target in human glioma.