TNBC accounts for approximately 15 to 20 percent of newly diagnosed breast cancers, is the most clinically aggressive and metastasizes more quickly than other subtypes of breast cancer,” explains Jessica Christenson, PhD, investigator at the CU Cancer Center and Post-Doctoral Fellow in JenniferRicher’s laboratory.

Lung metastasis in an animal model of breast cancer stained for AR.

“These tumors are also especially difficult to treat since, as their name implies, they do not express the most common breast cancer molecular markers, the estrogen receptor (ER), progesterone receptor (PR) or the growth factor HER2, that normally serve as therapeutic targets. Studies have shown that up to 50 percent of TNBCs express AR; however little has been done to understand how the receptor affects breast cancer metastasis to distant organs such as the lung.”

Christenson characterized AR expression in an immunocompetent animal model of breast cancer in order to learn more about TNBC primary tumor growth and metastasis.

She found that late-stage primary tumors and metastases, as well as Met-1 cells (derived from a late-stage primary tumor), expressed high levels of AR. When she treated the primary tumors with an anti-androgen, the second-generation AR-inhibitor enzalutamide, she found those tumors rely on AR for growth and are responsive to anti-androgen therapy.

Her data also suggests that AR may play a role in tumor progression from the primary site, specifically to the lungs.

Read more at Colorado Cancer Blogs.