Panoply™ Human WWP1 Knockdown Stable Cell Line

It has been reported that WW domain E3 ubiquitin ligase 1 (WWP1) is upregulated in various human cancers. However, its expression and function in intrahepatic cholangiocarcinoma (ICC) remain unclear. Here, researchers show that WWP1 is highly expressed in ICC, and high expression is associated with poor prognosis. Functionally, WWP1 overexpression enhances ICC cell proliferation and metastasis, and vice versa. Mechanistically, MYC may be enriched in the WWP1 promoter region, promoting its expression. Subsequently, WWP1 targets Nedd4 family interacting protein 1 (NDFIP1) and reduces NDFIP1 protein levels through ubiquitination. Downregulation of NDFIP1 in ICC cells reverses the effect of WWP1 expression silencing. Furthermore, WWP1 expression is negatively correlated with NDFIP1 protein levels in patient tissues. In conclusion, MYC upregulation of WWP1 promotes ICC progression through NDFIP1 ubiquitination, suggesting that WWP1 may be a potential therapeutic target for ICC.

Western blotting results showed that the WWP1 protein level in normal human intrahepatic bile duct epithelial cells (HIBEC) was significantly lower than that in four ICC cell lines (HCCC-9810, RBE, HuCCT1, and Huh28). Among the four ICC cell lines, the HuCCT1 cell line had the highest endogenous WWP1 expression level, while the other three cell lines had relatively low endogenous WWP1 expression levels (Figure 1A). Therefore, to investigate the biological function of WWP1, the researchers constructed a WWP1 knockdown HuCCT1 cell line (Figure 1B). Subsequently, they used the CCK-8 assay (Figure 1C), colony formation assay (Figure 1D), and EdU assay (Figure 1E) to assess the effect of WWP1 on the proliferation ability of HuCCT1 cells. The study showed that cell proliferation was inhibited in WWP1 knockdown HuCCT1 cells. In addition, Transwell assay results showed that the migration and invasion abilities of WWP1 knockdown HuCCT1 cells were significantly reduced (Figure 1F, G).

Figure 1. WWP1 silencing suppressed proliferation, migration, and invasion of HuCCT1 cells in vitro. (Li Y, et al., 2022)