BMP4 gene expression in AT/RT samples. (A) Expression of BMP4 mRNA in 18 AT/RT samples grouped by the molecular clusters defined in Fig. 1. Gene expression was measured by Affymetrix U133 Plus2 GeneChips. (B) The same BMP4 expression values as (A), plotted against survival time for the 17 patients included in the survival analysis (Fig. 2) (one patient was lost to follow-up).