A recent article published in The Scientist discusses a potential connection between Traveler's Diarrhea and the low incidence of colon cancer in developing nations.1 I wish to emphasize that this concept was first reported in Cancer Research and stems from our discovery that treatment of a mouse model of human colon cancer with the peptide hormone, uroguanylin, markedly reduces intestinal tumors.2
Uroguanylin is the natural regulator of cGMP production in the intestine, which is the signaling pathway also used by Escherichia coli heat-stable toxin (ST) peptides. We reasoned that periodic bouts of Traveler's Diarrhea elicited by bacteria that secrete ST peptides either prevent or markedly slow the appearance of intestinal adenomas. Activation of a receptor-guanylate cyclase (GC) by uroguanylin and guanylin clearly influences the growth of cultured colon cancer cells mediated by the intracellular second messenger, cGMP. The remarkable therapeutic efficacy of uroguanylin as an antitumor agent in the Min ...
