Mechanisms by which the risks of breast cancer and diabetes are combined

Population studies show that the risk of developing diabetes begins to increase two years after a breast cancer diagnosis.

Mouse pancreatic islet assessments. Photo: nature.

Breast cancer and type 2 diabetes seem to be distinctly different diseases, with only one point in common. However, previous research has found associations between these two diseases. Women with diabetes, for example, have a 20 to 27 percent increased risk of developing breast cancer.

Insulin resistance, a major feature of diabetes, is associated with the incidence of breast cancer and poor survival. Population studies show that the risk of developing diabetes begins to increase after two years Breast Cancer Diagnosis And that 10 years after diagnosis, the risk is 20 percent higher in breast cancer survivors than in women of the same age without breast cancer.

In the new study published in Nature Cell Biology, a research team led by scientists at the University of California San Diego School of Medicine describes a potential biological mechanism linking the two diseases, in which breast cancer suppresses insulin production, leading to diabetes, and poor glycemic control. In the blood promotes tumor growth.

“There is no island disease because no cell lives on its own,” explains study author Shizhen Emily Wang, associate professor of pathology at the University of California, San Diego School of Medicine. In this study, we describe how breast cancer cells disrupt the function of the pancreatic islets to produce less insulin than necessary, resulting in blood sugar levels top in Breast cancer patients Compared to women without cancer.

Wang notes that the study was inspired by early work and guidance provided by Jerrold Olewsky, MD, associate professor of medicine and associate dean for scientific affairs in the Department of Endocrinology and Metabolism at the University of San Diego School of Medicine. Olefsky is a co-author of the study with Wang.

The culprit, according to Wang and Olivsky, are extracellular vesicles (EVs), which are hollow spheres that secrete or secrete cells that carry DNARNA, proteins, lipids, and other intercellular materials, a Kind of communication system Pregnancy.

In this case, it was found that the cancer cells secrete microRNA-122 into the vesicles. Wang points out that when the vesicles reach the pancreas, they can enter the Responsible islet cells from insulin production, dispensing its payload of miR-122, and damage to islet function critical to maintaining a healthy level. normal blood glucose.

“Cancer cells have a very sweet tooth. They use more glucose than healthy cells to fuel tumor growth, and this was the basis for PET scans to detect cancer. Cancer cells and breast tumors make their favorite food, and at the same time, normal cells are deprived of this essential nutrient. Wang explains.

The research was conducted using mouse models, in which slow-release insulin pellets or a glucose-lowering drug known as an SGLT2 inhibitor have been found to restore normal glucose control in the presence of a breast tumor, which in turn suppresses tumor growth.

“These findings support the need for increased screening and prevention of diabetes among breast cancer patients and survivors,” Wang stresses, noting that an inhibitor of miR-122, developed by Regulus Therapeutics Inc. In San Diego, it is currently undergoing clinical trials as a potential treatment for chronic hepatitis C and has been found to be effective in restoring normal insulin production and suppressing tumor growth in mouse models of breast cancer.

“These miR-122 inhibitors, which happen to be the first mRNA-based drugs to enter clinical trials, could have new use in breast cancer treatment,” Wang said.

Source consult here.