Up-regulation of CD112 expression in gastric and colon cancers. (A) Specimens from human gastric and colon cancer tissues were stained with anti-CD112 mAb (TX31). Positive signals were observed in the poorly differentiated (black arrow), but not well-differentiated (white arrow), transformed epithelial cells in gastric cancer (left). The transformed epithelial cells also show the highly positive signal (black arrow) in colon cancer (right). (B) mRNA was obtained from gastric cancer tissues from 3 patients with poorly differentiated histologic type. In each patient, mRNA was also obtained from untransformed normal tissue area. RT-PCR was performed with Cd112-specific primers and the amount of cDNA was measured by quantitative PCR analysis. CD112 mRNA expression was normalized to the internal standard 18S ribosomal RNA.