Fig. 1

FGFRs expression in the NCI60 cell lines. a Hierarchical clustering analysis for immunohistochemical expression of FGFR1, FGFR2, FGFR3, and FGFR4. Three categories were defined. Category 1 (n = 29) consists relatively of low FGFR1, FGFR2, and FGFR4 expression. In contrast, category 3 (n = 20) consists exclusively of high FGFR1, FGFR2, and FGFR4 expression. Category 2 (n = 9) consists exclusively of low FGFR3 expression. b Correlation between FGFRs mRNA and protein expression. mRNA expression level was measured by microarray gene expression profiling, whereas the protein expression was assessed by immunohistochemistry. FGFR2 and FGFR4 protein expression was correlated with mRNA expression (P = 0.019 and P = 0.004, respectively)