UPMC researchers discover breast cancer mutation
Researchers at the University of Pittsburgh, Magee-Womens Research Institute and UPMC Hillman Cancer Center say they have uncovered new clues for potential improved treatments for breast cancer patients.
A research team identified a new genetic change in the estrogen receptor that hinders treatment of breast cancer in some patients.
This is the first time that estrogen fusion proteins have been identified in human breast tissue that has led to the understanding how they function. And that finding has the potential to lead to better treatments, the study's senior author said.
“We think we now have tools to measure changes to tumors that have become resistant to therapy,” said Adrian Lee, director of the Women's Cancer Research at MWRI and the UPMC Hillman Cancer Center.
“This, however, is really a first step.”
Estrogen Receptor – ER – breast cancer, which is 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 first treating the disease. But, ER-positive cancers often recur because the cancer develops a resistance to treatment. The estrogen fusion proteins sometimes split in half and eliminate the binding site anti-estrogen therapy targets.
“Physicians will continue administering anti-estrogen therapy, not realizing this genetic mutation has occurred,” Lee said. “Now that we understand the change, though, we can detect it with a blood test and improve treatments for this form of the disease.”
Lee said the mutation was identified in a patient who had ER-positive breast cancer and received anti-estrogen therapy. The patient's breast cancer recurred and she eventually passed away from the disease.
A member of Lee's team was performing a posthumous genetic analysis from tissue in UPMC's organ donation program and discovered the mutation, he said.
“Over time, we were able to identify many more cases of this mutation in patients with recurrent disease,” said Lee, adding that he predicts genetic analysis will soon be the dominant field of ER-positive breast cancer research. And that, in turn, will lead to both improved treatments and survival rates.
According to the American Cancer Society, around 266,120 new cases of invasive breast cancer will be diagnosed in women this year and around 40,920 will die from the disease. It is estimated to cause the death of one out of 38 women. It is the second-leading cause of death in women, only lung cancer kills more.
The findinds were published in the Jan. 19 issue of the journal Annals of Oncology.