Cancerpepsin Share Tweet An enzyme made in the stomach that breaks down proteins in food during digestion. Stomach acid changes a protein called pepsinogen into pepsin.( PEP-sin )Source: NCI Dictionary of Cancer TermsSearch the Glossary of Medical Terms Previous: PEP02 Next: pepsinogen NewsletterSign up for the QuackTrack.org newsletter below! Click to commentLeave a Reply Cancel replyYour email address will not be published. Required fields are marked *Comment *Name * Email * Website Save my name, email, and website in this browser for the next time I comment. Δ QuackTrack on TwitterTweets by QuackTrack_org Trending Posts