Abstract
BACKGROUND The spalt-like transcription factor 1 (SALL1) gene is a member of the Krüppel-associated box-containing zinc finger proteins (KRAB-ZFPs) and has been shown to modulate the onset and progression of human tumors. This study aimed to investigate the regulatory effects and mechanisms of SALL1 gene expression in human glioblastoma and glioma cells and tissue samples from patients with cerebral glioma. MATERIAL AND METHODS The human glioblastoma cell lines, LN229, U87-MG, U-251, U343, and the Hs683 glioma cell line were studied. The cell counting kit-8 (CCK-8) assay, cell cycle assay, wound-healing assay, transwell assay, Western blot, and quantitative real-time polymerase chain reaction (qRT-PCR) were used to evaluate cell proliferation, cell migration, and the cell cycle and expression of SALL1. Expression of SALL1 mRNA in 120 samples of cerebral glioma and 20 samples of normal brain were studied. Overall survival data from patients with cerebral glioma were analyzed. RESULTS SALL1 expression was down-regulated in human glioblastoma and glioma cells and in cerebral glioma tissues. Down-regulation of SALL1 expression was associated with reduced overall survival. Overexpression of SALL1 was associated with inhibition of cell proliferation associated with cell cycle arrest at the G0/G1 phase. SALL1 inhibited cell migration by preventing epithelial-mesenchymal transition (EMT) and down-regulating the expression of stem cell markers. Reduced levels of ß-catenin and downregulation of c-Myc and cyclin D1 and upregulation of p21and p27 expression were associated with SALL1 expression. CONCLUSIONS In human glioblastoma cells and cerebral glioma tissues, SALL1 acted as a tumor suppressor gene by inhibiting Wnt/ß-catenin signaling.