BCAT1 promotes cell proliferation, migration, and invasion via the PI3K‐Akt signaling pathway in oral squamous cell carcinoma

Abstract Objectives To analyze the expression, biological function of branched chain amino‐acid transaminase 1 (BCAT1) in oral squamous cell carcinoma (OSCC). Materials and Methods Real‐time PCR and immunohistochemistry were used to analyze the expression of BCAT1 protein in OSCC and normal oral tissues. Based on the clinicopathological information of patients, the relationship between the expression of BCAT1 protein and other clinicopathological factors was analyzed. Real‐time PCR and western blot assays were used to analyze the expression of BCAT1 gene and protein in normal human oral keratinocytes (HOK) and human OSCC cells, respectively. After BCAT1 overexpression or knockdown, the proliferation, cell cycle, migration, and invasion of human OSCC cells were analyzed by CCK8, flow cytometry, wound healing, and transwell invasion assays, respectively. After adding the BCAT1 inhibitor EGR240 to OSCC cells, the changes in cell proliferation, migration, and invasion ability in OSCC cells were analyzed. Based on the TCGA database, the involved signal pathway in BCAT1‐related and BCAT1‐binding genes was obtained for Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, verified by western blot assays. After inhibiting PI3K, the effect of BCAT1 on the expression of the downstream phosphorylated protein of the PI3K‐Akt signaling pathway was analyzed by western blot assays. The relationship between the expression of BCAT1 and EMT‐related protein of OSCC cells was also analyzed. Results The expression of BCAT1 gene and protein were upregulated in OSCC tissue, which positively correlated with the pathological grade of patients with OSCC. Compared with normal oral keratinocytes, BCAT1 gene and protein were upregulated in OSCC cells. BCAT1 overexpression promoted the proliferation, migration, and invasion of OSCC cells. BCAT1 knockdown or inhibition could reduce the proliferation, migration, and invasion abilities of OSCC cells. The results of bioinformatics analysis and Western bolt showed that BCAT1 could regulate the activation of PI3K‐Akt signaling pathway, and promote epithelial–mesenchymal transition (EMT) of OSCC cells. Conclusions BCAT1 could promote the proliferation, migration, and invasion of OSCC cells via PI3K‐Akt signaling pathway, which is a potential therapeutic target for OSCC.