Peripheral Opioid Antagonist Enhances the Effect of Anti-Tumor Drug by Blocking a Cell Growth-Suppressive Pathway In Vivo
Fig 1
PENK encoding opioid growth factor (OGF) is preferentially expressed in diffuse-type gastric cancers (GCs).
Representative histological image (hematoxylin-eosin, HE) and Ki-67 immunostaining of diffuse-type GC (A) and intestinal-type GC (B). Scale bar, 50 μm. C, supervised clustering analysis of 892 specifically expressed genes in 12 diffuse-type and 18 intestinal-type GCs. By the Wilcoxon u-test (p<0.05) and a 2-fold change, 188 genes were selected as specific genes for 18 intestinal-type GCs, and 704 genes were selected as specific genes for 12 diffuse-type GCs. The results of a two-dimensional hierarchical clustering analysis of the 892 selected genes are shown. D, RT-PCR analyses of OGF signaling molecules, PENK and its receptor OGFR, in diffuse-type and intestinal-type GCs.