According to a study by the National Institutes of Health obesity causes changes in the colon that may lead to colorectal cancer. The finding supports the recommendation that calorie control and frequent exercise are not only key to a healthy lifestyle, but a strategy to lower the risk for colon cancer, the second leading cause of cancer-related death in the United States.
Paul Wade, Ph.D., and Thomas Eling, Ph.D., scientists at the National Institute of Environmental Health Sciences (NIEHS), part of NIH, led a collaborative team that made the discovery. The study appeared in the journal Cell Metabolism. A large body of scientific literature says people who are obese are predisposed to a number of cancers, particularly colorectal cancer, Eling said.
The researchers looked for molecular clues, by isolating cells from the colons of the mice and analyzing a group of proteins called histones. Histones package and organize DNA in a cell’s nucleus, and sometimes undergo a process known as acetylation, in which chemical tags bind to their surface. The pattern of acetylation varies depending on the chemical processes taking place in the cell.
Wade and Eling want to find out exactly how obesity prompts the body to develop colorectal cancer. Wade said that the likely candidates for triggering tumor growth in the colon are fat cells, but there are many more possibilities. Finding these cellular switches may give rise to production of medications to keep people from getting colorectal cancer.
“Once we identify the signaling pathways and understand how the signal is transduced, we may be able to design ways to treat colorectal cancer in obese patients,” Wade said.