Diabetes Effects: Blood Sugar Problems May Increase Your Cancer Risk

There is a new reason to closely monitor your blood sugar levels. Diabetes has been found to be contributing to the risk of cancer. 

A new study shows that high blood sugar can damage DNA and slow down its healing process. These changes could then lead to increased risk of developing cancer in the ovary, breast and kidney, among other areas. 

Researchers said some diabetes medications available on the market, which reduce blood glucose levels, may also help prevent cancer. 

"It's been known for a long time that people with diabetes have as much as a 2.5-fold increased risk for certain cancers," John Termini, a researcher from City of Hope, a research and treatment center for cancer and diabetes, said in a statement. "As the incidence of diabetes continues to rise, the cancer rate will likely increase, as well."

Termini and his team analyzed mice with diabetes to see how elevated blood glucose levels can cause a DNA damage, called adducts. The researchers found that the adduct, N2-(1-carboxyethyl)-2'-deoxyguanosine (CEdG), appeared high in diabetic animals. 

Increased sugar levels also delayed the healthy cells’ capability to repair the damage. The team then gathered two people with type 2 diabetes to see if the same effects would happen in humans. 

Results showed that the people experienced the same impact of diabetes in mice. Higher blood sugar increased the participants’ CEdG adducts. 

"Exposure to high glucose levels leads to both DNA adducts and the suppression of their repair, which in combination could cause genome instability and cancer," Termini explained. 

Two proteins play a role in delaying DNA repair in people with diabetes. The transcription factor HIF1α and the signaling protein mTORC1 appeared less active in mice and humans with the disease. 

HIF1α supports the genes that work on fixing damaged DNA. The less active proteins could enable cancer to develop.

Termini said there are commercially available drugs, like metformin, which showed potential to prevent cancer in people with diabetes. These medications mainly help lower blood sugar levels and trigger DNA repair. 

"We're looking at testing metformin in combination with drugs that specifically stabilize HIF1α or enhance mTORC1 signaling in diabetic animal models," Termini added. 

Future research would focus on testing diabetes drugs in animal subjects to see how they can decrease cancer risk. 

Diabetes David Burns, 38, who has type 1 diabetes, prepares his insulin pen to inject himself in his home in North London on February 24, 2019. Health experts said "prediabetes" is not an actual disease or complication and that sudden elevated glucose levels does not always indicate the development of diabetes. Niklas Halle'n/AFP/Getty Images