Effect of Toxoplasma gondii on colon cancer growth in mouse model

Abstract

Despite all advances in cancer treatment methods, failure of treatment is a major concern. This failure can be caused by tumor environment made by tumor cells and prevents immune system to reach neoplastic cells. So, cancer immunotherapy and target therapy are in the focus of scientists. Due to the inverse relationship shown between parasites and cancer, parasites are a candidate for use in cancer immunotherapy. Toxoplasma gondii is an intracellular parasite invades many cells of vertebrae spices but make symptoms only in fetus and immuno-deficient person. Studies have shown T. gondii can stimulate immune system against neoplastic cells and break fort of tumor environment. In this experimental work, Colon cancer bearing mice randomly divided into three groups. Groups 1 and 2 were injected with either lysate or irradiated tachyzoite of T. gondii respectively. The third group were left intact as control group. Our resulted data showed that in irradiated tachyzoite or lysate treated groups there was a significant reduction in tumor growth in comparison with control group. However, the difference in survival time was not statistically significant. In conclusion, treatment with T. gondii antigens resulted in suppression of tumor growth. Keywords: Toxoplasma gondii; Cancer; Immunotherapy; Tumor; Mouse model