Polypeptide Biomarkers Predict Breast Tumor Aggressiveness

Cancer researchers have identified two polypeptide biomarkers that may help clinicians to predict the likelihood that a breast tumor will metastasize and spread to the lymph nodes and other organs.

Investigators at the John Wayne Cancer Institute (Santa Monica, CA, USA) studied a group of 65 patients with invasive cancers who underwent surgery and biopsy of the sentinel lymph node and/or other lymph nodes. Isolated proteins from tumors removed from these patients were applied to immobilized metal affinity capture (IMAC-3) ProteinChip arrays and analyzed by surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF-MS) to generate unique protein profiles.

Results published in the December 15, 2006, issue of Cancer Research revealed that a pattern of over-expression of a polypeptide of molecular weight 4,871 Da and under-expression of a polypeptide of molecular weight 8,596 Da was characteristic of those patients (37%) with two or more positive lymph nodes. Normal levels of these polypeptides were found in tissues from patients (63%) with no lymph node spread.
"We want to be able to predict, at the earliest stages, if a tumor has spread and how dangerous it will be,” said senior author, Dr. Dave S. B. Hoon, director of molecular oncology at the John Wayne Cancer Institute. "These two proteins may allow us to target aggressive tumors with more extensive therapy management to some women, while sparing others from needless treatment.”



Related Links:
John Wayne Cancer Institute