Panoply™ Human CDA Over-expressing Stable Cell Line

Cancer metastasis is a leading cause of cancer-related death, making it crucial to understand its underlying mechanisms. Here, researchers chose hepatocellular carcinoma (HCC), a highly malignant cancer, as their research model. Results showed that highly metastatic cell lines exhibited significantly stronger invasive capabilities than parental cells. Microarray analysis revealed overexpression of the cytidine deaminase (CDA) gene in highly metastatic cells, and the CDA gene is associated with resistance to systemic chemotherapy. Data analysis from the Cancer Genome Atlas Project (TCGA) showed that although CDA expression was downregulated in HCC, patients with high CDA expression often had poorer prognoses. Cellular models confirmed that CDA overexpression enhances cell migration and invasion, while CDA knockdown inhibits these abilities. By studying key molecules in the epithelial-mesenchymal transition (EMT), researchers found that CDA overexpression increases the expression of fascin, N-cadherin, β-catenin, and snail, while decreasing E-cadherin expression. Conversely, CDA knockdown produced the opposite results. In addition, researchers have found that CDA regulates the NF-κB signaling pathway, thereby controlling the expression of N-cadherin and promoting the invasive ability of liver cancer cells.

To analyze the function of CDA in hepatocellular carcinoma cell lines, researchers examined the expression levels of CDA protein in various hepatocellular carcinoma cell lines (Figure 1A). The results showed that CDA expression levels were low in SK-Hep-1, Hep3B, and Huh7 cells, while they were high in J7 and Mahlavu cells. Therefore, they selected SK-Hep-1 and Huh7 cells to construct stable CDA-overexpressing cell lines, and J7 cells to construct stable CDA-knockdown cell lines (Figure 1B). Transwell migration and invasion assays showed that stable CDA-overexpressing SK-Hep-1 cells (SK-CDA cells) exhibited stronger migration and invasion abilities compared to vector control cells (SK-Vec cells) (Figure 1C). The same results were observed in stable CDA-overexpressing Huh7 cells (Figure 1C). Conversely, stable CDA-knockdown J7 cells (J7-shCDA) showed lower migration and invasion abilities than vector control cells (Figure 1C). Since MMP2 and MMP9 are activated during tumor invasion, researchers examined the levels of precursor and active forms of MMP2 and MMP9 in stable CDA-overexpressing SK-Hep-1 cells. Figure 1D shows that precursor MMP9 expression was upregulated in SK-CDA cells compared to SK-Vec cells. However, MMP2 expression was not consistent across the three clones in each stable cell line. These results suggest that CDA promotes the migration and invasion of liver cancer cells, and that CDA-induced MMP9 expression may be involved in this process.

Figure 1. CDA is up-regulated in potent metastasis liver cancer cells and enhances the invasiveness of cells. (Liao C J, et al., 2025)