New study helps explain why type 2 diabetes increases cancer risk

Several recent scientific investigations have shown that individuals who have type 2 diabetes may also be prone to certain types of cancer. The increased risk is troubling, as there is little evidence explaining why this potential correlation exists. This makes effectively treating the problem difficult.

However, a new study may have determined one potential cause. Researchers from the Harvard Medical School reported in the journal Cell that the answer may have to do with two particular proteins.

In testing on lab mice, the researchers found that insulin sensitivity improved with higher levels of the proteins Lin28a and Lin28b when the mice were fed high-fat diets. Previous investigations have shown that these two proteins are also involved in a person's cancer risk. The team thinks that disruptions in levels of these proteins could account the diabetes-cancer connection.

"This highlights the overlap in the biology of these disorders," said George Daley, who led the study. "It may be the same kinds of metabolic shifts that allow cancer cells to grow are also related to [whole-body] glucose metabolism."

The study also identified a messenger molecule that turns on and off certain genes that may be associated with production of the Lin28 proteins. This opens the door to the development of potential medications that target this molecule, allowing doctors to more closely regulate individuals' Lin28 levels.

Such a medication could have important implications for both cancer and type 2 diabetes risk. Currently, individuals with the condition are generally advised to keep their blood sugar levels check. It has been speculated that excessive glucose in the blood may cause damage to cell, predisposing them to cancerous growths.

However, these hypotheses have proven unsatisfactory. Advancing the medical understanding of how type 2 diabetes increases cancer risk could lead to much more effective prevention strategies. This may allow many individuals with the metabolic disorder to stop worrying about their cancer risk and continue focusing on other areas of health.