Shared risk factors lead to diabetes, heart disease and cancer, says major AACR symposium

In a major symposium at the American Association for Cancer Research (AACR) Annual Meeting 2015, University of Colorado Cancer Center investigator Tim Byers, MD, MPH, describes research showing the link between cancer, diabetes and cardiovascular disease.

"We tend to silo ourselves in our research, but there are a number of risk factors shared in these three diseases," says Byers, the CU Cancer Center's associate director for cancer prevention and control.

For example, the World Cancer Research Foundation has concluded that obesity is a major cancer risk factor, likely causing about 20 percent of cancers of the breast, esophagus, colon, kidney, endometrium, pancreas, and gall bladder in the United States. Likewise, overweight and obesity contribute to diabetes and cardiovascular disease, causing 58 percent of type 2 diabetes and 21 percent of ischemic heart disease (according to the World Heart Federation).

"Obesity leads to a chronic inflammatory state and circulating growth factors that have adverse effects on the heart, and can also contribute to the development of cancer. But we tend to study these things in isolation, by disease and not by risk factor. The intention of this symposium is to plant a seed of thought that maybe, as cancer researchers, we should pay more attention to the subtleties of the epidemiology of other diseases," Byers says.

Shared risk factors for cancer, diabetes and cardiovascular disease also include, most importantly, tobacco, diet quality, physical activity and alcohol use.

Byers points out that each of the literatures describing scientific knowledge of cancer, diabetes and cardiovascular disease contains information useful to researchers in the other disciplines; however, researchers tend to overlook potentially useful information from outside their disease specialty.

"I was recently talking to a cardiovascular disease epidemiologist about cytokines - small proteins that can make inflammation and are jacked up in obesity," Byers says. "It turns out that in cancer we had focused on one kind of cytokine and in cardiovascular disease, they had focused on another. There was no good reason for the difference - it's just what was in the literature."

In this case and in many others, researchers from cancer, diabetes and cardiovascular disease have been, at times, unwitting working in parallel on related projects from different angles.

Overall, Byers hopes that by "stepping back to look system-wide," he says, researchers from many disciplines could collaborate and share knowledge, leading to a better understanding of how these risk factors work at the tissue, cellular and molecular levels to drive these diseases.

"Understanding the similarities and differences in how these risk factors create cancer, diabetes and cardiovascular disease could aid the ways we prevent all three diseases," Byers says.