Trypanosomiasis-induced megacolon illustrates how myenteric neurons modulate the risk for colon cancer in rats and humans.

• Published in: PLOS Neglected Tropical Diseases
• Main Authors: Vinicius Kannen, Enio C de Oliveira, Bruno Zene Motta, Annuar Jose Chaguri, Mariângela Ottoboni Brunaldi, Sérgio B Garcia
• Format: Article in Journal/Newspaper
• Language: English
• Published: Public Library of Science (PLoS) 2015
• Subjects: Arctic medicine. Tropical medicine; RC955-962; Public aspects of medicine; RA1-1270; Arctic
• Online Access: https://doi.org/10.1371/journal.pntd.0003744; https://doaj.org/article/d971f97cb990412181cb9a26d0c58baf

BACKGROUND:Trypanosomiasis induces a remarkable myenteric neuronal degeneration leading to megacolon. Very little is known about the risk for colon cancer in chagasic megacolon patients. To clarify whether chagasic megacolon impacts on colon carcinogenesis, we investigated the risk for colon cancer in Trypanosoma cruzi (T. cruzi) infected patients and rats. METHODS:Colon samples from T. cruzi-infected and uninfected patients and rats were histopathologically investigated with colon cancer biomarkers. An experimental model for chemical myenteric denervation was also performed to verify the myenteric neuronal effects on colon carcinogenesis. All experiments complied the guidelines and approval of ethical institutional review boards. RESULTS:No colon tumors were found in chagasic megacolon samples. A significant myenteric neuronal denervation was observed. Epithelial cell proliferation and hyperplasia were found increased in chagasic megacolon. Analyzing the argyrophilic nucleolar organiser regions within the cryptal bottom revealed reduced risk for colon cancer in Chagas' megacolon patients. T. cruzi-infected rats showed a significant myenteric neuronal denervation and decreased numbers of colon preneoplastic lesions. In chemical myenteric denervated rats preneoplastic lesions were reduced from the 2nd wk onward, which ensued having the colon myenteric denervation significantly induced. CONCLUSION/SIGNIFICANCE:Our data suggest that the trypanosomiasis-related myenteric neuronal degeneration protects the colon tissue from carcinogenic events. Current findings highlight potential mechanisms in tropical diseases and cancer research.