KRT7 and breast cancer: Blood samples of 20 BC patients (24.7%) which contained more than 8 CTCs/ml with CD45-EpCAM+CK7/8- and/or CD45-EpCAM-CK7/8+ and/or double-positive CD45-EpCAM+CK7/8+ phenotypes were used for further enrichment procedure and scRNA-seq.