Suzanne A. W. Fuqua, PhD, professor of medicine at Baylor College of Medicine, discusses the 

Fuqua says there is a fairly high frequency of this mutation in metastatic breast cancers. These mutations are estrogen independent, meaning that hormones are not needed to activate the receptor. The clinical assumption is that the mutation would confer resistance to an aromatase inhibitor, Fuqua says. However, there is no direct clinical evidence of this because the majority of patients that have been examined have undergone multiple rounds of hormonal therapy.

Videos

Suzanne A. W. Fuqua, PhD, professor of medicine at Baylor College of Medicine, discusses the Y537 hotspot in breast cancer.

Suzanne Fuqua Discusses the Y537 Hotspot in Breast Cancer

Suzanne A. W. Fuqua, PhD, professor of medicine, Baylor College of Medicine, says that it is an exciting time for the treatment of patients with metastatic breast cancer.

Many women today are consenting to biopsy their metastatic lesions, which is the only way to learn about the mechanisms that evolve during the course of treatment. A metastatic tumor is not the same as a primary tumor, Fuqua says, as it evolves both with and as a function of treatment.

Biopsied lesions allow for the discovery of many new mechanisms of resistance that are targetable. Fuqua says that there are drugs available today that can be combined with hormonal therapies in this space.

Suzanne Fuqua on Biopsying Metastatic Tumors

Suzanne A. W. Fuqua, PhD, professor of medicine, Baylor College of Medicine, talks about the interaction between estrogen receptors (ER) and androgen receptors (AR) in patients with breast cancer.

Fuqua says receptors, like AR and ER, can bind together at non-genomic sites and elicit one effect, like protein kinase B/Akt. Receptors can also bind together on DNA to help regulate genes, which cause proliferation, Fuqua says.

The basic biology is becoming clear that receptors are acting together, Fuqua says, raising the need for combination therapies when treating patients with breast cancer.

Suzanne Fuqua on the Interaction Between ER and AR

Suzanne A. W. Fuqua, PhD, professor of medicine at Baylor College of Medicine, discusses the androgen receptor in breast cancer.

In her presentation at the 12th International Congress on the Future of Breast Cancer from July 18-20, 2013, in Huntington Beach, CA, Fuqua discussed the role of the androgen receptor for the treatment of breast cancer. Fuqua says that this is an exciting time because there are several drugs involving the androgen receptor that are available to treat prostate cancer that can be repurposed for use in patients with breast cancer.

In a previous study, Fuqua looked at hormone-resistant metastatic disease and found that the androgen receptor was unregulated. Since then, emphasis has been placed on studying the androgen receptor as a mechanism of resistance. It has been seen that when the androgen receptor is overexpressed in a patient with estrogen receptor (ER)+ breast cancer, androgen receptor-targeted agents are useful in restoring hormone sensitivity.

Further, there is a large body of work showing that the androgen receptor may be important in ER- breast cancer. Perhaps, Fuqua says, the mechanism is similar to ER+ disease: the androgen receptor collaborates with other growth factor receptors, the HER3 receptor in ER- disease, or the estrogen receptor in ER+ disease.

In the next year, Fuqua predicts that researchers will learn whether the androgen receptor is the driver of the tumor or an escape mechanism from treatment.

Suzanne A. W. Fuqua, PhD, on the Androgen Receptor

Suzanne A. W. Fuqua, PhD, professor of medicine at Baylor College of Medicine, explains that the rapid pace of preclinical research has led to an explosion in possible biological targets; however, research into new therapeutics for these targets has progressed more slowly.

Fuqua believes the reason that research into therapies for the vast number of new biological targets has progressed more slowly is because many trials fail to incorporate the use of predictive biomarkers in their design. She believes that adding mandatory tissue sampling to clinical trials may help speed up the discovery process.

Once predictive biomarkers can be discovered simultaneously to new therapeutics there will be a rapid dissemination of new targeted therapies in practice, Fuqua suggests.

Suzanne Fuqua, PhD, from the Baylor College of Medicine, on the Utilization of Predictive Biomarkers

Suzanne A. W. Fuqua, PhD

Articles

Suzanne Fuqua Discusses the Y537 Hotspot in Breast Cancer

Suzanne Fuqua on Biopsying Metastatic Tumors

Suzanne Fuqua on the Interaction Between ER and AR

Suzanne A. W. Fuqua, PhD, on the Androgen Receptor

Suzanne Fuqua on Utilizing Predictive Biomarkers