title: COX2 expression predicts resistance to chemoradiotherapy in esophageal squamous cell carcinoma.
abstract: OBJECTIVE
  The overexpression of cyclooxygenase (COX)2 is correlated with carcinogenesis, tumor progression, and prognosis, and increased COX2 expression is correlated with radiation resistance. However, no correlation between the COX2 expression and resistance to chemoradiotherapy for esophageal squamous cell carcinoma has been characterized. The purpose of the present study was to evaluate whether COX2 expression is an indicator of resistance to chemoradiotherapy in esophageal squamous cell carcinoma and the feasibility of COX2 as a biomarker for CRT.
  
  
  METHODS
  Fifty-eight patients who were diagnosed with esophageal squamous cell carcinoma from biopsy samples were enrolled in the present series. All patients underwent concurrent chemoradiotherapy in a neoadjuvant setting, followed by radical esophagectomy. COX2 expression was evaluated by immunohistochemical staining and statistically compared with the histopathologic findings in surgically resected specimens.
  
  
  RESULTS
  The rate of responders was 87% for weak expression of COX2, 62% for moderate expression, and 30% for strong expression, and there was a close correlation between COX2 expression and the response rate (Kendall's τb = 0.396, P = 0.001). In the univariate analysis, negative or weak expression of COX2 was found to correlate significantly with CRT response (odds ratio, 6.296; 95% confidence interval (CI), 1.58-25.096; P = 0.010). In the multivariate analysis, weak expression of COX2 (30% or less) was found to be an independent prognostic factor (odds ratio, 6.534; 95% CI, 1.535-27.803; P = 0.011).
  
  
  CONCLUSIONS
  The COX2 expression predicts resistance to chemoradiotherapy in esophageal squamous cell carcinoma, and it also is a feasible biomarker for evaluating the CRT response.
authors: Department of Frontier Surgery, Graduate School of Medicine, Chiba University, Chiba, Japan. yakutsu@faculty.chiba-u.jp
authors: Yasunori
authors: Y
authors: Akutsu
authors: Naoyuki
authors: N
authors: Hanari
authors: Gulbostan
authors: G
authors: Yusup
authors: Aki
authors: A
authors: Komatsu-Akimoto
authors: Norimasa
authors: N
authors: Ikeda
authors: Mikito
authors: M
authors: Mori
authors: Yasuo
authors: Y
authors: Yoneyama
authors: Satoshi
authors: S
authors: Endo
authors: Yukimasa
authors: Y
authors: Miyazawa
authors: Hisahiro
authors: H
authors: Matsubara
mesh_terms: D000328:Adult; D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D014408:Biomarkers, Tumor / Q000378:metabolism; D002294:Carcinoma, Squamous Cell / Q000378:metabolism / Q000473:pathology / Q000628:therapy*; D059248:Chemoradiotherapy; D002945:Cisplatin / Q000008:administration & dosage; D015331:Cohort Studies; D051546:Cyclooxygenase 2 / Q000378:metabolism*; D019008:Drug Resistance, Neoplasm; D004938:Esophageal Neoplasms / Q000378:metabolism / Q000473:pathology / Q000628:therapy*; D005260:Female; D005472:Fluorouracil / Q000008:administration & dosage; D005500:Follow-Up Studies; D006801:Humans; D007124:Immunoenzyme Techniques; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D012189:Retrospective Studies; D015996:Survival Rate; D016896:Treatment Outcome
chemical_list: D014408:Biomarkers, Tumor; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human; D002945:Cisplatin; D005472:Fluorouracil