title: Analysis of epithelial-cadherin and human epidermal growth factor receptor 2/ expression in gastric carcinoma using immunohistochemistry.
abstract: BACKGROUND
  Gastric adenocarcinoma (GAC) is a common malignancy with high mortality-rate. Analysis of molecular markers could form a foundation for the future use of targeted therapies to reduce morbidity and mortality.
  
  
  OBJECTIVE
  To find the prevalence and relation of epithelial cadherin (E-cadherin) and human epidermal growth factor receptor 2 (HER-2/neu) protein expression with histological type and grade of GAC using immunohistochemistry (IHC).
  
  
  METHODS
  A total of 100 cases of GAC diagnosed over a 2 year period were studied. Expression of E-cadherin and HER-2/neu was analyzed by IHC in relation to the histological type and grade.
  
  
  RESULTS
  Of the 100 cases of GAC studied, 11 revealed a loss of E-cadherin and over-expression of HER-2/neu was seen in 17 cases. Loss of E-cadherin was seen in 50% of signet ring-cell carcinomas but only in 8% of tubular and none of papillary and mucin-secreting GAC (P = 0.003). Of all the cases of tubular GAC with loss of E-cadherin expression, majority (71.4%) were Grade III (P = 0.04). Of all the tubular GAC cases with an over-expression of HER-2/neu, 20% and 67% were Grade I and II GAC respectively while only 13% were Grade III (P < 0.001).
  
  
  CONCLUSIONS
  Although poorly-differentiated tumors show loss of E-cadherin, better-differentiated tumors over-express HER-2/neu protein. Signet ring-cell carcinoma is more likely to exhibit a loss of E-cadherin protein. Targeted therapy toward HER-2/neu in GAC should be considered. Novel therapy to block E-cadherin down-regulation is justified.
authors.affiliation: Department of Pathology, Army Hospital Research and Referral, Delhi Cantt, New Delhi, India.
authors.forename: Khushboo
authors.initials: K
authors.lastname: Dewan
authors.forename: Renu
authors.initials: R
authors.lastname: Madan
authors.forename: Prasanta
authors.initials: P
authors.lastname: Sengupta
authors.forename: Reena
authors.initials: R
authors.lastname: Bharadwaj
mesh_terms: D000230:Adenocarcinoma / Q000175:diagnosis* / Q000473:pathology*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015820:Cadherins / Q000032:analysis*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods*; D008297:Male; D008875:Middle Aged; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000032:analysis*; D012720:Severity of Illness Index; D013274:Stomach Neoplasms / Q000175:diagnosis* / Q000473:pathology*
chemical_list: D015820:Cadherins; D018719:Erb-b2 Receptor Tyrosine Kinases; C508053:ERBB2 protein, human