Aberrant NSG1 Expression Promotes Esophageal Squamous Cell Carcinoma Cell EMT by the Activation of ERK Signaling Pathway.

Abstract

Neuron-specific gene family member 1 (NSG1) is a 21kDa endosomal protein that is specifically expressed in neurons. This study was to explore the expression of NSG1 and possible mechanism in Esophageal Squamous Cell Carcinoma (ESCC). The Cancer Genome Atlas (TCGA) database was consulted to analyze the expression of NSG1 in ESCC. Immunohistochemistry (IHC) staining was used to evaluate NSG1 expression in ESCC cancerous tissues and matched paracancerous tissues. The CCK-8 assay, wound-healing assay, and transwell assay were used to detect the cell viability, migration, and invasion of ESCC cells. Western blot was used to assay epithelial-mesenchymal transition (EMT)-related proteins and ERK signaling pathway protein expression. The results showed that the expression of NSG1 in ESCC cancerous tissues was higher than noncancerous tissues. Compared with negative control (NC) group, cell viability, migration. and invasion significantly increased, the expression of p-ERK in ERK signaling pathway was significantly upregulated, the expressions of mesenchymal marker Vimentin and EMT-related transcription factors including snail and slug were significantly upregulated, and the expression of epithelial marker E-cadherin was significantly downregulated in KYSE-150 cells with NSG1 overexpression. However, these effects were reversed by the ERK signaling pathway inhibitor U0126. On the other hand, TE-1 cells with NSG1 knockdown had the changes contrary to that in KYSE-150 cells with NSG1 overexpression. NSG1 plays a potential carcinogenic role on the occurrence and progression of ESCC, and aberrant NSG1 expression might promote ESCC cell EMT by the activation of ERK signaling pathway.