Expression of CXCR4 and TNF-α mRNA in primary gastric cancers by real-time PCR. (A) and (B) H. pylori-positive gastric cancers (grey columns, n = 19) expressed higher level of CXCR4 (A) and TNF-α (B) mRNA compared to H. pylori-negative gastric cancers (black columns, n = 15), *P < 0.01. Horizontal lines: means of mRNA level. (C) Level of CXCR4 mRNA was correlated positively with that of TNF-α mRNA in 34 gastric cancers, P < 0.01. Black rhombus: H. pylori-negative gastric cancers; grey rhombus: H. pylori-positive gastric cancers.