Downregulation of CBX2 inhibited glioma cell proliferation, invasion, and self-renewal. (A) The data (UALCAN, http://ualcan.path.uab.edu/index.html) showed that the expression of CBX2 was higher than that in normal brain tissue (P < .001). (B) The level of CBX2 was higher in glioma tissues. And with the increase of glioma grade, the expression of CBX2 increased, the expression of CBX2 in Grade IV glioma tissues was the highest. (C and D) The expression of CBX2 was analyzed in glioma cell lines by RT-PCR and western blotting. (E and F) CBX2-shRNA transfection efficiencies were verified by RT-PCR and western blotting (P < .001). (G and H) CCK-8 and colony formation assays demonstrated that CBX2-shRNA-mediated knockdown of CBX2 decreased the proliferation of glioma cells (P < .01). (I) Transwell assays showed that CBX2 downregulation reduced invasion compared to that in the scramble group. (J) Sphere formation analysis showed that the downregulation of CBX2 decreased the glioma stem cell frequencies (P < .05). (K) Knockdown of CBX2 reduced the levels of N-cadherin, slug, and snail and increased the level of E-cadherin.
Abbreviations: CBX, ChromoBox; CCK-8, cell counting kit-8; qRT-PCR, quantitative real-time PCR.