Fig. 4

Differential cell surface receptor expression on CO and RE cancer cell lines as compared to other tumor cell lines. a Shown is the relative MFI of each of the depicted receptors of each CO (n = 7, left) or RE (n = 8, right) cell line in comparison to all other tumor cell lines in the NCI-60 panel (NCI). Each symbol represents the specific cell surface receptor expression MFI of one cell line. Statistical significance of overall differences in receptor expression (MFI) of CO or RE versus all other cell lines was calculated with a one-way ANOVA with multiple comparisons and a Kruskal–Wallis test assuming non-gaussian distribution. b Primary FACS plots from representative cell lines of the various tumor entities. Plotted is the size of the cells (forward scatter, FSC) vs. the relative fluorescence expression of the respective cell surface marker (PE, mean fluorescence intensity, MFI). Note that no representative FACS plots are shown for ovarian cancer (OV), breast cancer (BR), prostate cancer (PR) and lung cancer (LC) because these cancer entities did not form clusters based on flow cytometric receptor expression (compare Fig. 2)