Detection of gastric cancer and premalignant lesions by novel marker glycoprotein 87 using monoclonal antibody Adnab-9.

Gastric adenocarcinoma (GC), the second most frequent cancer in the world, is highly prevalent in Asia. A screening test for early-stage GC would represent a major advance in the management of this disease. Associated conditions such as chronic atrophic gastritis (CAG) with intestinal metaplasia are manifested by specialized intestinalized tissue that often includes Paneth cells. Adenoma-associated antigen glycoprotein 87 (GP87), defined by the Adnab-9 monoclonal antibody and shed into the gut, is associated with epithelial cells, some of which resemble Paneth cells. We evaluated the diagnostic value of GP87 for cancer and gastric premalignant lesions. One hundred and seven sections of normal, benign, and premalignant gastric mucosa and 79 sections of pericancerous tissue were evaluated for expression of GP87 by immunohistochemistry. Eighty-two patients with GC, 34 patients with benign chronic disease, 35 patients with premalignant conditions, and 80 normal controls were evaluated by ELISA for GP87 in feces and gastric juice. Adnab-9 immunostaining for GP87 was significantly positive in CAG and intestinal metaplasia (>77.8%), compared with 0% in normal controls (P < 0.05). Fecal GP87 was positive in 79.3% of patients with gastric cancer, including early-stage lesions, and in 84% of patients with CAG versus 10% of controls (P < 0.05). Positive proportions for each pathological group in tissue correlated with that in feces (r = 0.99; P < 0.02). GP87 is differentially expressed in premalignant gastric lesions that appear to be the origin for fecal GP87, which may be useful for early detection of GC.