WDR5 Promotes Proliferation and Correlates with Poor Prognosis in Oesophageal Squamous Cell Carcinoma.

The WD40 protein family member WD repeat domain 5 (WDR5) plays significant roles in the tumorigenesis and development of multiple organ tumours. However, the correlation between WDR5 expression and oesophageal squamous cell carcinoma (ESCC) has not been elucidated. WDR5 mRNA expression data were acquired from The Cancer Genome Atlas (TCGA) database, and the expression and prognostic potential of WDR5 were assessed by immunohistochemistry (IHC) and Western blot. The cell counting kit-8 (CCK-8), colony formation assay and cell cycle evaluation were performed to verify the WDR5 function in vitro. The xenograft model was used to verify WDR5 function in vivo. The mRNA and protein expression levels of WDR5 were significantly upregulated in ESCC tissues compared with expression in adjacent normal tissues. Kaplan-Meier analysis showed that high WDR5 expression in ESCC patients was associated with poor overall survival (P=0.004). Multivariate analysis revealed that WDR5 overexpression emerged as an independent predictor of poor overall survival (P=0.013) in ESCC. The in vitro and in vivo experiments revealed that downregulation of WDR5 expression blocked cell proliferation of ESCC. Mechanistically, we found that WDR5 may influence ESCC proliferation by targeting the PI3K/AKT/mTOR signalling pathway. Our data demonstrate that overexpression of WDR5 was associated with poor prognosis in patients with ESCC and that WDR5 may act as a potential novel prognostic biomarker for ESCC.