Expression profiling of EGC and AGC. (a) Hierarchical clustering of 415 probe sets differentially expressed (FC>2 and P<0.05), by Affymetrix analysis, in AGCs (n=19) and EGCs (n=9). (b) Hierarchical clustering of the 10 representative genes on AGC (n=9) and EGC (n=8) samples based on Q-PCR data. (c) Data relative to both the Affymetrix analysis on 28 tumors (right) and the Q-PCR analysis on a subset of 17 tumors (left) of the 10 genes selected for validation. The probe set number and the gene symbol are indicated. For each gene in the two classes of samples median normalized average expression values were calculated, and relative fold changes and t-test P-values are displayed relative both to the Affymetrix (right) data and Q-PCR data (left). Asterisk indicates no significant P-value. Rows, probes; columns, samples. Sample code: blue, AGC; red, EGC. Topology code: black, cardias; grey, antrum; light blue, fundus; violet, body. Grade code: black, G3; dark gray, G2; light gray, G1.