CCNE1 and central nervous system cancer: To provide further evidence regarding the mechanisms underlying the effects of NDRG1 on glioma cells, the present study examined the expression levels of proteins associated with glioma cell proliferation (cyclin D1, cyclin E, Ki-67 and PCNA), apoptosis (Bcl-2/Bax, Bcl-xL, cleaved-PARP, cleaved-caspase-3, p-AKT and AKT), and invasion (N-cadherin, vimentin and E-cadherin) by western blot analysis.