Food proteins must be broken down into amino acids that your body uses for tissue growth, maintenance and repair. The enzyme called trypsin, present in pancreatic juice, is essential for efficient protein digestion. Disorders of trypsin production can not only hinder digestive processes, they can damage the pancreas. Trypsin production in tissues other than the pancreas may be involved with the cancer process.
Trypsin is a protein-digesting enzyme present in pancreatic juices secreted into your small intestine during a meal. Your pancreas secretes trypsin as an inactive proenzyme called trypsinogen. Once in the intestine, an enzyme called enteropeptidase, which is secreted from intestinal cells, cuts off a small piece of trypsinogen to produce the active trypsin enzyme. Activated trypsin, in turn, helps break down food proteins. It also activates other trypsinogen molecules, as well as other protein-digesting enzymes secreted as proenzymes with pancreatic juice. Therefore, trypsin is essential for normal function of digestive processes that convert food proteins into amino acids for absorption.
Trypsin inhibitors are compounds that can bind tightly to trypsin and block its protein-digesting capabilities. An example of natural dietary substances that inhibit trypsin activity are the Bowman-Birk inhibitors found in soybeans and some other legume and cereal grain seeds. Eating large amounts of foods containing active trypsin inhibitors can lower the nutritional quality of food proteins. Cooking foods largely inactivates dietary trypsin inhibitors, however. The cells in your pancreas produce another type of trypsin inhibitor that blocks premature activation of trypsin and other protein-digesting enzymes while they are still in the pancreas. This prevents your pancreas from self-digesting.
Some people are born with mutations in a portion of the genetic material that codes for trypsinogen production in the pancreas. These rare hereditary disorders can alter trypsinogen structure and produce a condition whereby trypsinogen activation to trypsin is no longer properly regulated and tissue trypsin inhibitors no longer properly work. Portions of the pancreas may self-digest, which leads to pancreatitis, or inflammation in the pancreas. Inappropriate trypsin activation and inflammation in pancreatic tissue may also occur with heavy alcohol consumption or if a gallstone blocks the pancreatic secretory duct. Pancreatitis is a serious condition that may cause irreversible tissue damage and loss of secretions needed for normal digestive processes.
Trypsin and Cancer
Small amounts of trypsin can be found in tissues other than the pancreas, including other digestive organs, skin, kidney, liver, brain and immune system cells, where it may be involved with some normal cell processes. Although their exact role in the cancer process is unclear, trypsin and tumor-associated trypsin inhibitor may be produced at high levels in cancerous tissues. For example, increased production is found in a large percentage of colorectal tumors, according to a report published in the October 2003 issue of "Histology and Histopathology." Increased production in cancerous tissue may be associated with poor cancer prognosis.