Enhancement of apoptosis in Caco-2, Hep-G2, and HT29 cancer cell lines following exposure to Toxoplasma gondii peptides.

Objective: Cancer or neoplasm is a cosmopolitan catastrophe that results in more than 20 million new cases and 10 million deaths every year. Some factors lead to carcinogenesis like infectious diseases. Parasites like Toxoplasma gondii, by its components, could modulate the cancer system by inducing apoptosis. The objective of this investigation is to assess the potential of peptides derived from T. gondii in combating cancer by examining their effects on Caco-2, Hep-G2, and HT29 cell lines.

Materials and methods: Candidate peptide by its similarity to anticancer compounds was predicted through the computer-based analysis/platform. The impact of the peptide on cell viability, cell proliferation, and gene expression was evaluated through the utilization of MTT assay, flow cytometry, and real-time polymerase chain reaction (PCR) methodologies.

Results: The cell viability rate exhibited a significant decrease (p < 0.001) across all cell lines when exposed to a concentration of ≤160 μg. Within the 48-hour timeframe, the half maximal inhibitory concentration (IC₅₀) for HT29 and Hep-G2 cell lines was determined to be 107.2 and 140.6 μg/mL, respectively. Notably, a marked decrease in the expression levels of Bcl2 and APAF1 genes was observed in both the Hep-G2 and HT29 cell lines.

Conclusion: These findings indicate that the T. gondii peptide affected cancer cell mortality and led to changes in the expression of genes associated with apoptosis.