[Proteomics and breast cancer: a search for novel diagnostic and theragnostic biomarkers].

A major challenge of breast cancer research is the identification of accurate biomarkers that improve screening, early diagnosis, prediction of aggressiveness and prediction of therapeutic response or toxicity as well as the identification of novel molecular therapeutic targets. Following the sequencing of the human genome and pioneer developments of transcriptomics, analysis of the proteome (the repertoire of proteins expressed in a biological samples) was recently introduced as a promising tool in the study of biology of human cancers. In spite of their current limitations, proteomics, either array-based (such as tissue microarrays, antibody arrays or reverse phase protein microarrays) or mass spectrometry-based, make possible to envision major improvements in the molecular knowledge of breast cancer and for the identification of tissue-based or circulating diagnostic and theragnostic biomarkers relevant to this disease. The current techniques applied to clinical samples of breast cancer and the most important results obtained are summarized in this review.