The presence of the fragment, called p95HER-2, in breast cancer tissue correlates closely with lymph node metastasis and earlier recurrence of the disease, suggesting that p95HER-2 is a marker and perhaps even involved in metastasis.
The study builds on observations the investigators have published over the last five years about the role of the HER-2 oncogene in breast cancer. HER-2, a growth factor receptor, is overexpressed in 20% to 30% of breast cancer cases, but it has had limited usefulness in predicting clinical outcomes, particularly in early-stage breast cancer.
“More work is needed to determine if the presence of p95 has any significance regarding responsiveness of the cancers to chemotherapy, anti-estrogen therapy or Herceptin,” said Dr Edward Keenan, one of the authors of the study, and professor of physiology and pharmacology, OHSU School of Medicine. “Hopefully, understanding the significance of this marker will help us better specify effective therapy for individual patients.”