BMI and expression of estrogen receptor affect HER2 expression in luminal B breast cancer
The multifactorial and heterogeneous nature of breast cancer continues to fascinate researchers and is newly confirmed by a study, published in the Journal of Cell Physiology (2014; doi:10.1002/jcp.24891).
“Breast cancer is a complex disease. Such complexity is faithfully mirrored by its clinical phenomenology and etiopathogenesis, namely, the way several risk factors may combine according to mechanisms characterized by flexibility and heterogeneity with alternative and innovative patterns changing from patient to patient,” said Maddalena Barba, MD, senior researcher at the Regina Elena Cancer Institute in Rome, Italy.
This study's multidisciplinary Italian-American research team was led by Antonio Giordano, MD, PhD, Director of the Sbarro Institute for Cancer Research and Molecular Medicine at Temple University, in Philadelphia, Pennsylvania. They focused on the specific breast cancer subtype luminal B.
“Within this context, the expression of receptor known as human epidermal growth factor receptor 2 (HER2) is a widely recognized factor in treatment assignment and patients' clinical management. This makes the evaluation of factors associated with HER2 expression particularly appealing to a research agenda” said Barba.
Barba explained that this study analyzed data from 154 women with luminal B breast cancer. They found an inverse association between body mass index (BMI), an established link between obesity and insulin resistance, percentage of estrogen receptor (ER) expression, and HER2 expression.
“This seemed to indicate that HER2 expression was significantly less common among luminal B breast cancer patients with the highest BMI and ER expression compared to their respective counterparts,” said Barba.
She said that the research may contribute key dowels to the complex puzzle of luminal B-like breast cancer, particularly when considered jointly with a bunch of easily measurable parameters accounting for visceral adiposity (eg, waist circumference). This approach might help better identify the host profile and disease characteristics in view of an increasingly precise therapeutic approach.
Giordana concluded that patient outcomes could ultimately be improved by identifying patient subcategories for who may best benefit from the use of co-interventions specifically addressing insulin resistance in well-defined breast cancer scenarios.