Stanford University School of Medicine researchers found that a compound derived from vitamin A - retinoic acid, inhibit the mouse and human colorectal cancer plays an important role. Related results recently published in "Immunology" periodicals.
Levels of metabolites in the intestine of cancer mice were lower than normal levels. In addition, if some colorectal cancer patients with high levels of intestinal tissue expression of a degradable retinoic acid protein, then they are often worse than the performance of other patients.
For the first time, this study unravels a complex "dance" relationship between retinoic acid levels, immune-related inflammation and intestinal microbiology, and may provide a new approach to prevent or treat human colorectal cancer.
"There is a clear link between the progression of human inflammatory bowel disease (including ulcerative colitis) and colorectal cancer," said Edgar Englema, a senior author and professor of pathology and medicine at the University of Pennsylvania. Inhibit intestinal inflammation, and we hope to link these together to find out whether and how the level of retinoic acid directly affects the development of cancer.
Using quantitative mass spectrometry, Retinoic acid Tretinoin the researchers measured the levels of retinoic acid in the intestine of mice treated with two chemicals, one of which could cause intestinal inflammation and the other could stimulate the development of colorectal cancer. A group of mice developed intestinal tumors within 9 to 10 weeks, while those treated with the first chemical showed intestinal inflammation but not cancer.
The levels of retinoic acid in the intestine of colorectal cancer mice were significantly lower than those of mice with intestinal inflammation but no development of cancer. Further investigation revealed that the yield of a protein that produced a synthesis of retinoic acid in cancer mice was lower, while the other protein that degraded retinoic acid increased about fourfold. Similar changes in protein levels were also observed in tissue samples from patients with colorectal cancer (but without a history of ulcerative colitis).
Further studies have shown that retinoic acid blocks or slows the progression of cancer by activating an immune cell called CD8 T cells. These T cells then kill the cancer cells.
