FAM83D promotes the progression of 4NQO-induced esophageal carcinoma via inhibiting FBWX7.

ABSTRACT

The present study aimed to explore the expression and regulatory role of FAM83D in the different developmental stages of esophageal squamous cell carcinoma (ESCC) to determine the effect of FAM83D on the proliferation, migration, and invasion of ESCC cells and to elucidate its underlying molecular mechanism. Immunohistochemistry (IHC) analysis revealed that the expression of FAM83D was obviously elevated in ESCC tissues compared to adjacent normal tissues. Furthermore, the FAM83D levels was positively correlated with tumor size, TNM stage, T stage, and N stage, while it was negatively correlated with FBXW7 expression, Karnofsky Performance Status (KPS) score, and survival rate. Subsequently, ESCC cell lines with low FAM83D expression were constructed using RNA interference technology to investigate the impact of FAM83D on the biological behavior of ESCC cells. Silencing of FAM83D inhibited the proliferation and migration of ESCC cells but promoted apoptosis. Furthermore, a reduction in FAM83D expression may also induce cell cycle arrest at the G0/G1 phase and regulate the expression of proteins related to epithelial-mesenchymal transition (EMT), the cell cycle, and apoptosis. Further research indicated that silencing FAM83D led to the upregulation of FBXW7 expression. These results suggested that FAM83D may exert its effects on ESCC by downregulating FBXW7. Additionally, using a 4NQO solution in the drinking water to establish an ESCC mouse model, IHC analysis revealed that FAM83D expression levels were positively correlated with the pathological grade of esophageal lesions in the mice and negatively correlated with the expression levels of FBXW7 and E-cadherin. The above results demonstrated that FAM83D may facilitate the progression of ESCC by negatively regulating FBXW7 expression and that FAM83D could represent a promising therapeutic target for ESCC.