By some estimates, people with type 2 diabetes can have up to a 30 percent increased risk for colorectal cancer. Christian Rask-Madsen, M.D., Ph.D., Assistant Investigator in the Section on Vascular Cell Biology, and Assistant Professor at Harvard Medical School, is investigating why in a series of experiments recently funded by the National Institutes of Health (NIH).
One prevailing theory as to why this happens has to do with insulin resistance. Insulin, aside from serving as the gatekeeper for getting glucose into cells, also acts as a growth hormone. In people with insulin resistance, the body floods itself with insulin in attempts to get the glucose into cells, a situation known as hyperinsulinemia. According to this theory, the excess insulin promotes the growth of cancer cells. This idea is well supported by research, but experiments from Dr. Rask-Madsen’s lab seem to suggest there’s more at play, and the culprit is likely to turn out to be inflammation.