Hematoxylin and eosin staining of well-differentiated carcinoma of esophagus (a), adenocarcinoma of gastroesophageal junction (d), and gastric adenocarcinoma (g). Immunorecognition of 14F7 Mab in before-mentioned tumors (b, e, h). Note a moderate (finely granular) and strong reactivity located on plasmatic membrane and cytoplasm of malignant epithelial cells. For negative controls (c, f, i), tissues were stained as described in Section 2 without 14F7 Mab. No staining occurred in control sections. Black bar = 50 μm.