Molecular mimicry between parasites and cancer: a novel approach for developing cancer vaccines and therapeutic antibodies

Cancer is one of the most dreaded diseases worldwide. Conventional treatments such as surgery, chemotherapy, and radiotherapy have limitations and adverse effects. Cancer immunotherapy and targeted therapies offer new treatment options. Parasite-based cancer therapy shows promise in fighting tumors. Some parasites have anti-cancer properties through multi-mechanistic strategies, with the molecular mimicry theory as a leading explanation for parasites' anti-cancer effects. This study aimed to explore the existence of shared antigenic proteins between parasites (Trichinella spiralis, Schistosoma mansoni, and Toxoplasma gondii) and cancer cell lines (MCF-7 human breast cancer and A549 human lung cancer). Polyclonal antisera against T. spiralis, S. mansoni, and T. gondii parasites were generated in rabbits. Antibody reactivity with extracts of MCF-7 and A549 cancer cells was detected using SDS-PAGE and immunoblotting. Results documented the molecular mimicry between parasites and cancers as it revealed cross-reactive bands when using T. spiralis antibodies against MCF-7 and A549 cancer cell extracts at approximate molecular weights of 70 and 35 kDa, and with S. mansoni antibodies at an approximate molecular weight of 80 kDa. Toxoplasma gondii antibodies neither reacted with MCF-7 human breast cancer nor A549 human lung cancer cell extracts. Results of this study could establish a foundation for subsequent investigation among a broad range of parasites for molecular mimicry with cancers. Identification, molecular characterization, and investigation of the anti-neoplastic activity of these cross-reactive antigens could shed light on new pathways for the potential development of a novel class of innovative cancer vaccine candidates and therapeutic antibodies of parasitic origin for cancer immunotherapy and targeted therapy.