title: Epidermal growth factor expression in esophageal adenocarcinoma: a clinically relevant target?
abstract: BACKGROUND
  There has been recent widespread enthusiasm in epidermal growth factor (EGFR) as a molecularly active target in esophageal adenocarcinoma (EAC). However, there is limited data on the extent of EGFR expression in EAC. Thus, the aim of this study was to evaluated EGFR, pErk1/2, and total Erk1/2 expression in malignant and benign specimens.
  
  
  METHODS
  Baseline expression of EGFR in the human normal squamous, Barrett's, and EAC cell lines were determined as well as after bile acid treatment and curcumin pretreatment. In addition, EGFR expression was also evaluated in 60 matched normal and malignant EAC resected specimens.
  
  
  RESULTS
  The in vitro studies in the Het-1a, BarT, and OE19 cell lines failed to show any measurable expression of EGFR via Western blot technique. The marker serving as the positive control for the study, MnSOD, showed expression in each cell line for all three treatment regimens at approximately 24 kDa EGFR, showing moderate staining in the malignant tumor specimens and low staining in the benign tissue specimens. pErk1/2 showed low staining in the malignant tumor specimens and no staining in the benign tissue specimens. Total Erk1/2 showed high staining in both the malignant tumor specimens and benign tissue specimens. The differences in the mean staining scores for the malignant versus benign tissue specimens for pErk1/2 and total Erk1/2 are not statistically significant (p = 0.0726 and p = 0.7054, respectively).
  
  
  CONCLUSIONS
  Thus, in conclusion, EGFR expression has been confirmed to be limited to non-existent in EAC and thus its use as a clinically active target is limited at best. Prior to the use of these expensive anti-EGFR therapies, confirmation of overexpression should be verified.
authors.affiliation: Division of Surgical Oncology, Department of Surgery, University of Louisville, 315 E. Broadway, Louisville, KY 40202, USA.
authors.forename: Nicholas
authors.initials: N
authors.lastname: Harper
authors.forename: Yan
authors.initials: Y
authors.lastname: Li
authors.forename: Russell
authors.initials: R
authors.lastname: Farmer
authors.forename: Robert C G
authors.initials: RC
authors.lastname: Martin
mesh_terms: D000230:Adenocarcinoma / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D015153:Blotting, Western; D004815:Epidermal Growth Factor / Q000235:genetics* / Q000378:metabolism; D004938:Esophageal Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007150:Immunohistochemistry; D066298:In Vitro Techniques; D012016:Reference Values; D012494:Sampling Studies; D012680:Sensitivity and Specificity; D018709:Statistics, Nonparametric; D014407:Tumor Cells, Cultured
chemical_list: D004815:Epidermal Growth Factor
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