Figure 4. Anti-5-methyl-C IHC showing loss of CpG methylation in myofibroblasts of primary gastric carcinomas.
The upper and lower panels show IHC with anti-ASMA and anti-5-methyl-C, respectively. The control non-neoplastic gastric mucosa (Normal) was sampled at a location in the gastrectomy distant from an intestinal type carcinoma. The ASMA-positive spindle-shaped myofibroblasts of the normal muscularis mucosae show strong nuclear staining with anti-5-methyl-C (large arrow), as do the normal epithelial cells (small arrow) and leukocytes (lymphocytes and polymorphonuclear cells; asterisk). The more rare ASMA-positive intraepithelial myofibroblasts also showed uniformly strongly stained in multiple sections examined (example; arrowhead). Sections from within the cancers in 2 cases of intestinal type gastric carcinomas (CA; Case 1 and Case 2) show myofibroblasts (large arrows) and malignant epithelial cells (small arrows) with reduced IHC intensity of 5-methyl-C. As in internal control, the anti-5-methyl-C staining of infiltrating leukocytes remains strong in the neoplastic tissue (asterisks).
