Potassium Benzoate Induced Cytotoxicity via Alteration of Gene Expression-Associated Apoptosis and Cell Cycle Genes in Tumor Cell Lines

Certain food preservatives, including potassium benzoate, have been shown to possess carcinogenic properties. This study investigated the cytotoxic effects of potassium benzoate, a common food additive, on HepG2 liver cancer cells and THLE2 non-tumorigenic liver cells. Using the Neutral Red assay, we observed a concentration-dependent decrease in cell viability for both cell lines, with HepG2 cells showing higher sensitivity. The IC50 values were determined to be 72.50 µg/mL for HepG2 cells and 645.7 µg/mL for THLE2 cells, indicating potassium benzoate's potential cytotoxicity on both malignant and non-malignant cells. Flow cytometry analysis revealed that potassium benzoate treatment induced G2/M phase arrest in HepG2 cells, with a significant increase in the proportion of cells in the G2/M phase from 12% to 43%. Gene expression analysis using qRT-PCR demonstrated upregulation of p53, Bax, and p21, while Bcl-2, cyclin B1, and CDK1 were downregulated. These findings suggest that potassium benzoate has a high potential for cytotoxicity and genotoxicity when used as a food preservative. This study contributes to the growing body of evidence on the potential health impacts of food additives and underscores the need for further research into their long-term effects on human health.