High blood insulin levels may contribute to worse outcomes in Black women with triple-negative breast cancer compared with White women with the disease, according to new findings presented by Engel et al at the Endocrine Society’s Annual Meeting & Exposition 2024.
Background
Triple-negative breast cancer—accounting for about 10% to 15% of all breast cancer cases—is characterized by breast cancer cells that lack estrogen and progesterone receptors as well as produce any or much of the HER2 protein. The breast cancer subtype differs from other types of invasive breast cancer in that it tends to grow and spread faster, has fewer treatment options, and has a worse prognosis.
“Obesity and type 2 diabetes, which are more common in Black women, are associated with poor breast cancer outcomes,” stressed study author Alexis Engel, BA, of the Icahn School of Medicine at Mount Sinai. “Black women have higher rates of triple-negative breast cancer and have a greater risk of death from breast cancer in comparison to White women,” she continued.
Study Methods and Results
In the new study, investigators analyzed the tumor samples of 45 Black women and 48 White women with triple-negative breast cancer for cellular signs of increased sensitivity to growth from insulin—with the goal of determining whether high levels may promote cancer growth and metastasis, decrease outcomes, and contribute to breast cancer disparities.
The investigators discovered that the signs of sensitivity to insulin were more prevalent in the tumors from Black women compared with those from White women. Insulin signaling was also correlated with obesity and high blood insulin levels.
Conclusions
“These results suggest that high insulin levels in Black women may be contributing to cancer growth and worse breast cancer outcomes,” Ms. Engel concluded.
