Higher Levels of HSET Linked to More Aggressive Breast Cancers and Worse Outcomes in African American Women
Data from a study by Ritu Aneja, PhD, Associate Professor in the Department of Biology at Georgia State University in Atlanta, and colleagues indicate that overexpression of the protein HSET is a valuable prognostic biomarker in African American women with breast cancer, but not in Caucasian patients, underscoring the protein’s role in the aggressiveness of the disease in African American women. The findings were presented at the Sixth American Association for Cancer Research (AACR) Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved.
According to Dr. Aneja, although breast cancer incidence is higher in Caucasian women, African American women are more likely to be diagnosed with breast cancer at a younger age than non-Hispanic white women and are more likely to have cancers that metastasize, recur, or result in death.
“The reason for poorer outcome is also because [African American women] are two to three times more likely to present with the triple-negative signature. And having the triple-negative signature carries a higher risk of recurrence and metastasis, especially to the brain, and lower survival,” said Dr. Aneja. “Nuclear HSET levels can predict worse outcomes.”
Study Methods and Findings
The researchers analyzed breast tumor samples from 149 African American women and 44 non-Hispanic white women, looking for levels of HSET to evaluate whether the protein could be a clinical breast cancer biomarker in ethnically distinct populations. They found that nuclear HSET expression was highly associated with race—African American patients were three times as likely to present with nuclear localization compared to Caucasian women, regardless of triple-negative status.
In addition, the researchers found that high HSET expression was associated with poorer outcomes in African American patients but not in Caucasian patients. Within the African American population subset, patients with the highest tertile of HSET expression demonstrated the poorest overall survival (hazard ratio [HR] = 4.1, P = .007), progression-free survival (HR = 3.0, P = .014), and metastasis-free survival (HR = 3.5, P = 0.01). According to the study results, overall survival, progression-free, and metastasis-free survival were significantly associated with nuclear but not cytoplasmic HSET.
This information could offer oncologists a means of stratifying African American patients with triple-negative disease and high HSET levels, Dr. Aneja noted.
The study was funded by the National Cancer Institute. Dr. Aneja reported no conflicts of interest.
The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.
