title: Prognostic value of p53 protein and MK-1 (a tumor-associated antigen) expression in gastric carcinoma.
abstract: BACKGROUND
  MK-1, the target molecule of FU-MK-1, is encoded by the GA733-2 gene, which is currently being used as a target in clinical trials for gastric, intestinal and biliary cancer treatment with monoclonal antibodies. Also of interest is p53, a protein that has been intensively investigated in relation to particular types of tumors, patterns of metastases, tumor stage, and prognosis.
  
  
  METHODS
  The expression of p53 protein and MK-1 antigen was investigated in specimens from 42 patients with gastric carcinoma. The specimens were stained by the avidin-biotin peroxidase technique for immunohistochemical examination.
  
  
  RESULTS
  MK-1 was positive in 21 (50%) of the 42 cases. MK-1 expression was more frequent in cardia tumors (71%), in large (>3 cm) tumors (60%-64%), and in specimens from patients with more than five metastatic lymph nodes (69%). p53 expression was present in 20 (48%) of the 42 cases. Of these 20 patients, 15 (52%) had tubular adenocarcinoma (TA) and 5 (38%) had signet ring cell carcinoma. p53 expression was more frequent in the tumors of male patients (55% vs 27%); in poorly differentiated TAs (60% vs 47% in well-to-moderately differentiated TAs); in smaller tumors (< or = 3 cm, 72% vs 43%-50% in larger tumors); in patients with a prominent inflammatory response (61% vs 21%; P < 0.02); and in patients with lymphatic vessel invasion (77% vs 34%; P < 0.02). However, p53 expression was less frequent in the presence of more than five metastatic lymph nodes (23% vs 60% for five or fewer nodes; P < 0.05). Most patients with p53- and MK-1-positive gastric carcinomas and those more than five metastatic lymph nodes had a poor prognosis.
  
  
  CONCLUSIONS
  The study found that the expression of both p53 and MK-1 was frequent in aggressive gastric carcinomas; however, extensive lymph node involvement (more than five nodes) was the only significant factor related to overall survival.
authors.affiliation: Department of Pathology, Gülhane Military Medical Academy, Etlik, Ankara, Turkey.
authors.forename: M Salih
authors.initials: MS
authors.lastname: Deveci
authors.forename: Güzin
authors.initials: G
authors.lastname: Deveci
mesh_terms: D000230:Adenocarcinoma / Q000378:metabolism* / Q000556:secondary / Q000601:surgery; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000951:Antigens, Neoplasm / Q000378:metabolism*; D014408:Biomarkers, Tumor / Q000378:metabolism*; D018279:Carcinoma, Signet Ring Cell / Q000378:metabolism / Q000556:secondary; D015815:Cell Adhesion Molecules / Q000378:metabolism*; D000071858:Epithelial Cell Adhesion Molecule; D005260:Female; D005743:Gastrectomy; D006801:Humans; D007124:Immunoenzyme Techniques; D008198:Lymph Nodes / Q000378:metabolism / Q000473:pathology; D008207:Lymphatic Metastasis / Q000473:pathology; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D013274:Stomach Neoplasms / Q000378:metabolism* / Q000473:pathology / Q000601:surgery; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism*
chemical_list: D000951:Antigens, Neoplasm; D014408:Biomarkers, Tumor; D015815:Cell Adhesion Molecules; C499379:EPCAM protein, human; D000071858:Epithelial Cell Adhesion Molecule; D016159:Tumor Suppressor Protein p53