Article

Proteomic-Based Biosignatures in Breast Cancer Classification and Prediction of Therapeutic Response

Gonda/UCLA Breast Cancer Research Laboratory, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, CA 90095, USA.
International journal of proteomics 10/2011; 2011(2090-2166):896476. DOI: 10.1155/2011/896476
Source: PubMed

ABSTRACT Protein-based markers that classify tumor subtypes and predict therapeutic response would be clinically useful in guiding patient treatment. We investigated the LC-MS/MS-identified protein biosignatures in 39 baseline breast cancer specimens including 28 HER2-positive and 11 triple-negative (TNBC) tumors. Twenty proteins were found to correctly classify all HER2 positive and 7 of the 11 TNBC tumors. Among them, galectin-3-binding protein and ALDH1A1 were found preferentially elevated in TNBC, whereas CK19, transferrin, transketolase, and thymosin β4 and β10 were elevated in HER2-positive cancers. In addition, several proteins such as enolase, vimentin, peroxiredoxin 5, Hsp 70, periostin precursor, RhoA, cathepsin D preproprotein, and annexin 1 were found to be associated with the tumor responses to treatment within each subtype. The MS-based proteomic findings appear promising in guiding tumor classification and predicting response. When sufficiently validated, some of these candidate protein markers could have great potential in improving breast cancer treatment.

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