KRT19 and breast cancer: In this study, we attempted to quantify transcripts of one marker considered relatively specific for epithelial cells, cytokeratin-19 (CK-19), and of a more breast-tissue-specific cell marker, mammaglobin (MAM), in both the PB and BM of patients with BC using quantitative real-time reverse transcription (RT)–PCR according to the Taqman methodology.