When looking at gene expression patterns in relation to GMP status (78 cases available from the doxorubicin-treated series), statistical analysis of microarrays (SAM) between GMP-positive and -negative tumours revealed that 76 genes were significantly downregulated in GMP-positive cases (none were significantly upregulated; false discovery rate 20%), five of these genes more than twofold: NAT1 (N-acetyltransferase 1), ESR1 (estrogen receptor 1), TFF3 (trefoil factor 3), PLAT (plasminogen activator, tissue), and HIST2H2BE (histone cluster 2, H2BE). The gene discussed is NAT1; the disease is neoplasm.