The Impact of Helminths on Colorectal Cancer: From Infections to the Isolation of Biotherapeutics

Worldwide, colorectal cancer (CRC) is the third-most common cancer and the second-leading cause of cancer-related deaths. The inflammatory response initiated by pathogens, environmental and dietary factors, and inflammatory bowel diseases can promote the formation of colorectal tumors. The hygiene hypothesis proposes an inverse link between inflammatory diseases and early childhood exposure to pathogens, with a significant negative correlation between chronic inflammatory diseases and helminth infections. On the other hand, it is also known that several pathogens may influence or even cause the development of cancer, including helminth infections. How do helminth infections influence CRC outcomes? The existing literature presents two different perspectives. Experimental studies in CRC models suggest that helminths may accelerate disease progression and lead to worse outcomes (such as Schistosoma and Trichuris sp.), while others indicate that helminths could help reduce tumor burden (such as Taenia sp.). This review focuses on helminths' pro- and anti-tumorigenic effects and their derivatives, specifically in CRC. We provide a comprehensive understanding of how helminths impact the macroscopic, histopathological, immunological, and molecular aspects of CRC.