Abstract
Considerable evidence indicates a negative correlation between the prevalence of some parasitic infections and cancer and their interference with tumor growth. Therefore, parasitic antigens seem to be promising candidates for cancer immunotherapy. In this study, the therapeutic efficacy of autoclaved Schistosoma mansoni and Trichinella spiralis antigens against a colon cancer murine model was investigated. Both antigens showed immunomodulatory potential, as evidenced by a significant decrease in serum IL-17, a significant increase in serum IL-10, and the percentage of splenic CD4(+)T-cells and intestinal FoxP3(+) Treg cells. However, treatment with S. mansoni antigen yielded protection against the deleterious effect of DMH-induced colon carcinogenesis only, with a significant decrease in the average lesion size and number of neoplasias per mouse. For the first time, we report an inhibitory effect of S. mansoni antigen on the progression of chemically induced colon carcinogenesis, but the exact mechanism has yet to be clarified. This anti-tumor strategy could introduce a new era of medicine in which a generation of anticancer vaccines of parasitic origin would boost the therapy for incurable cancers.