Figure 4

(A) Composite image gallery of MDA-MB-231 cells, MCF7 cells and WBCs from manually stained CellSearch Profile samples visualised on the DEPArray system. Images of a single MCF7 cell showing faint EPCAM-PE staining (row 1), a single MDA-MB-231 cell showing no EPCAM staining (row 2) and two EPCAM-/CD45+ WBCs (rows 3 and 4) are shown. (B) Unsupervised hierarchical clustering analysis comparing gene expression profiles of 1 to 10 MDA-MB-231 cells, MCF7 cells and WBCs isolated from spiked blood samples with the CellSearch Profile kit and the DEPArray system and corresponding positive control samples (PC). Data have been subjected to median normalisation for each individual marker across all samples. Red colour indicates a transcript level above the median and green colour indicates a transcript level below the median of the particular assay as measured in all samples. (C) Boxplots of normalised gene expression values of 1 to 10 MDA-MB-231 and MCF7 cells and two groups of 10 WBCs for the 9 marker transcripts. PC=positive control sample cDNA of 3–5 million MDA-MB-231 cells harvested from the same culture flask as the one used to perform the isolation of single cells and groups of tumour cells); NTC=negative template control; TC=tumour cell(s); WBC=white blood cell.