Original western blot.

<div><p>Hepatocellular carcinoma (HCC) is characterized by a lack of obvious clinical features in the early stages and is likely to progress to advanced HCC. Advanced HCC is a highly malignant tumor. However, there are few treatment options for advanced HCC. Therefore, screening for new drugs that target HCC will provide a new approach to the treatment of HCC. The CCK8 assay was performed to screen compounds inhibiting HCC cell proliferation and to evaluate the IC<sub>50</sub> (half-maximal inhibitory concentration) of compounds on cell lines. Colony formation assay was used to determine HCC cell proliferation. The effect of compounds on HCC cell migration and invasion were analyzed using wound healing and transwell assays, respectively. Tumor growth and metastasis were assessed <i>in vivo</i> in a xenograft mouse model. Flow cytometry was carried out to measure apoptotic cells. Reverse transcription and quantitative real-time polymerase chain reaction (RT‒qPCR) and Western blot were performed to examine the expression of epithelial-mesenchymal transition (EMT)- and apoptosis-related genes. Through large-scale screening, we have discovered the anti-tumor activity of cetylpyridinium chloride (CPC) against HCC cells. CPC inhibited the proliferation, invasion and metastasis of HCC cells. Cancer cells are more sensitive to CPC than normal cells. CPC suppressed HCC tumor growth and metastasis <i>in vivo</i>. Mechanistically, CPC promoted apoptosis of HCC cells by affecting the expression of apoptosis-related genes, and inhibited HCC invasion and metastasis by suppressing EMT and expression of EMT markers. Our investigation showed that CPC significantly inhibited HCC cell proliferation, invasion and metastasis <i>in vivo</i> and <i>in vitro</i>, by inducing the expression of apoptosis-related genes and inhibiting expression of EMT markers, suggesting that CPC is a potential agent for HCC treatment.</p></div>