Researchers solving treatment resistance in most common breast cancer

February 7, 2018, University of Pittsburgh Schools of the Health Sciences
breast cancer
Mammograms showing a normal breast (left) and a breast with cancer (right). Credit: Public Domain

At Magee-Womens Research Institute (MWRI) and UPMC Hillman Cancer Center, a large team of clinical and laboratory researchers dedicated to understanding treatment resistance in the most common form of breast cancer have identified a new genetic change in the estrogen receptor (ER) that contributes to therapy resistance. ER-positive breast cancer, diagnosed in two-thirds of breast cancer patients, is fueled by the presence of estrogen in the body. Anti-estrogen therapy is usually successful in treating the disease initially, but ER-positive breast cancers will often recur because tumors develop a resistance to treatment.

Published in the Annals of Oncology, the research identifies the presence of ER gene (ESR1) fusion proteins in treatment-resistant . This is the first time that recurrent ESR1 fusion proteins have been identified in human breast , and understanding how they function could lead to improved treatments for the disease.

"We first identified this change in a patient who had ER-positive breast cancer, received anti-estrogen therapy, had her breast cancer recur and eventually passed away from the disease," said senior author Adrian Lee, Ph.D., director of the Women's Cancer Research Center at MWRI and UPMC Hillman Cancer Center, and professor of Pharmacology & Chemical Biology at the University of Pittsburgh. "A member of our lab noticed the mutation while performing posthumous genetic analysis from tissue in our organ donation program, and over time we were able to identify many more cases of this mutation in patients with recurrent disease." This work was performed in collaboration with Foundation Medicine Inc., a genomic testing company that examined ESR1 fusions in close to 10,000 breast cancers sequenced with the FoundationOne CDx test.

According to Lee, ESR1 fusion proteins "outsmart" traditional by splitting in half and eliminating the binding site that anti-estrogen therapy targets.

"Physicians will continue administering anti-estrogen therapy, not realizing this genetic mutation has occurred," said Lee. "Now that we understand the change, though, we can detect it with a blood test and help improve treatments for this form of the disease."

According to Lee, genetic analysis will soon be the dominant field of ER-positive , eventually leading to improved treatments and patient outcomes.

"Genomic sequencing is telling us so much about breast cancer. I believe the research we are doing in the laboratory will have a significant clinical impact in the near future, and the work we are doing will play a large part in improving patient care and survival," said Lee.

Explore further: Newly-identified gene mutation could help explain how breast cancer spreads

Related Stories

Newly-identified gene mutation could help explain how breast cancer spreads

December 12, 2014
A newly-identified genetic mutation could increase our understanding of how breast cancer spreads and potentially guide treatment options for women with the disease, according to a study from Magee-Womens Research Institute ...

Novel therapeutic target discovered for estrogen receptor positive (ER+) breast cancer

November 17, 2017
Researchers at the Icahn School of Medicine at Mount Sinai have identified a protein that can be targeted to suppress growth of a common type of breast cancer known as "estrogen receptor positive" (ER+), including ER+ cancers ...

Blood samples analysis finds ESR1 gene mutations prevalent, associated with worse overall survival

December 10, 2015
Among patients with estrogen receptor (ER)-positive, metastatic breast cancer, those who had a D538G and/or a Y537S mutation in the estrogen receptor 1 (ESR1) gene, as detected in cell-free DNA obtained from patient blood ...

Analysis of blood samples finds ESR1 gene mutations are prevalent and associated with reduced survival

December 10, 2015
Among patients with estrogen receptor (ER)-positive, metastatic breast cancer, those who had a D538G and/or a Y537S mutation in the estrogen receptor 1 (ESR1) gene, as detected in cell-free DNA obtained from patient blood ...

Pregnancy poses no greater risk to breast cancer survivors

October 26, 2017
A recent study published in the Journal of the National Cancer Institute indicates that pregnancy does not incur a greater risk of relapse for survivors of breast cancer. The safety of pregnancy for women with history of ...

Prevalence of estrogen receptor mutations in patients with metastatic breast cancer

August 11, 2016
A new study published online by JAMA Oncology examines the prevalence and significance of estrogen receptor mutations in patients with metastatic breast cancer.

Recommended for you

Fully reprogrammed virus offers new hope as cancer treatment

May 25, 2018
A cancer treatment that can completely destroy cancer cells without affecting healthy cells could soon be a possibility, thanks to research led by Cardiff University.

Research could help fine-tune cancer treatment

May 25, 2018
Cancer therapies that cut off blood supply to a tumour could be more effective in combination with existing chemotherapeutic drugs—according to new research from the University of East Anglia.

Increasing physical activity linked to better immunity in breast cancer patients, study finds

May 25, 2018
A new study from the University of Toronto's Faculty of Kinesiology & Physical Education has found that moderate to vigorous physical activity may help regulate the levels of C-reactive protein – an important biomarker ...

Low-fat diet tied to better breast cancer survival

May 24, 2018
(HealthDay)—Breast cancer patients who adopted a low-fat diet were more likely to survive for at least a decade after diagnosis, compared to patients who ate fattier fare, new research shows.

A cascade of immune processes offers insights to triple-negative breast cancer

May 24, 2018
Cancer is crafty. To survive and thrive, tumors find a way of thwarting our body's natural systems.

By forming clots in tumors, immune cell aids lung cancer's spread

May 24, 2018
University of North Carolina Lineberger Comprehensive Cancer Center researchers have found that by helping to form clots within tumors, immune cells that flock to a particular type of lung cancer are actually building a foundation ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.