title: Expression of p53, bcl-2, and bax as predictors of response to radiotherapy in esophageal cancer.
abstract: The sensitivity of cancers to radiotherapy or chemotherapy may be influenced by susceptibility to apoptosis. We evaluated whether expression of three proteins regulating apoptosis, p53, bcl-2, and bax, could predict the effect of radiotherapy in esophageal cancers. We used immunohistochemical staining for these protein regulators of apoptosis to study biopsy specimens obtained from 25 patients with esophageal squamous cell carcinoma before they underwent preoperative radiotherapy. Effectiveness of radiotherapy was assessed by barium esophagography, esophagoscopy, and computed tomography. Radiotherapy was effective in 12 patients and ineffective in 13 patients. Biopsy specimens from the 25 patients showed expression of p53, bcl-2, and bax to be 48.0%, 32.0%, and 76.0% respectively. Effectiveness of radiotherapy was correlated with p53 expression (p = 0.047), but bcl-2 and bax expression showed no relationship to effectiveness of radiotherapy. Expression of p53 protein in biopsy specimens may predict effectiveness of preoperative radiotherapy in esophageal cancers.
authors.affiliation: First Department of Surgery, University of the Ryukyus, School of Medicine, Okinawa, Japan. hshimoji@med.u-ryukyu.ac.jp
authors.forename: H
authors.initials: H
authors.lastname: Shimoji
authors.forename: H
authors.initials: H
authors.lastname: Miyazato
authors.forename: A
authors.initials: A
authors.lastname: Nakachi
authors.forename: S
authors.initials: S
authors.lastname: Kuniyoshi
authors.forename: T
authors.initials: T
authors.lastname: Isa
authors.forename: M
authors.initials: M
authors.lastname: Shiraishi
authors.forename: Y
authors.initials: Y
authors.lastname: Muto
authors.forename: T
authors.initials: T
authors.lastname: Toda
mesh_terms: D000368:Aged; D002294:Carcinoma, Squamous Cell / Q000378:metabolism* / Q000532:radiotherapy* / Q000601:surgery; D004938:Esophageal Neoplasms / Q000378:metabolism* / Q000532:radiotherapy* / Q000601:surgery; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D011518:Proto-Oncogene Proteins / Q000378:metabolism*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism*; D018714:Radiotherapy, Adjuvant; D016896:Treatment Outcome; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism*; D051028:bcl-2-Associated X Protein
chemical_list: C494826:BAX protein, human; D011518:Proto-Oncogene Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D016159:Tumor Suppressor Protein p53; D051028:bcl-2-Associated X Protein