title: Expression of Bcl-2 but not Bax has a prognostic significance in tongue carcinoma.
abstract: BACKGROUND
  Among the molecular mechanisms involved in carcinogenesis, defects in the regulation of programmed cell death (apoptosis) make important contributions to the pathogenesis and progression of cancer. Apoptosis regulatory genes include the antiapoptotic bcl-2 gene and the proapoptotic bax gene. The aim of this study was to determine the spectrum of Bax and Bcl-2 expression, and to correlate these findings with clinicopathologic variables and prognosis.
  
  
  METHODS
  In this study we have evaluated the immunohistochemical expression of Bcl-2 and Bax proteins in a series of 35 squamous cell carcinomas of the tongue.
  
  
  RESULTS
  Immunoreactivity for Bax was detected in 37.1% and for Bcl-2 in 8.6% of cells, and for both proteins the staining was cytoplasmic and granular. Bcl-2 and Bax expression was mainly seen in peripheral cells of epithelial tumor islands with decreasing immunoreactivity toward the center of the neoplastic nests. Bax immunoexpression was significantly correlated with histologic grading (P=0.05), but not with the remaining clinicopathologic variables. Bcl-2 immunoreactivity was significantly correlated with N-stage (P=0.01) and survival. Patients with Bcl-2-negative tumors [mean survival: 73.97 months; 95% confidence interval (CI): 59-88] vs. Bcl-2-positive ones (mean survival: 17.67 months; 95% CI: 6-29) had a longer survival (P=0.01; odds ratio=6.9).
  
  
  CONCLUSIONS
  Bcl-2 is associated with aggressive disease, neck lymph node metastasis, and poor prognosis. Whereas Bax is related with histologic grade.
authors.affiliation: Servicio de Cirugía Maxilofacial, Hospital Universitario Central de Asturias, Facultad de Medicina y Odontología, Instituto Universitario de Oncología del Principado de Asturias (IUOPA), Oviedo, Spain. jvicente@uniovi.es
authors.forename: Juan Carlos
authors.initials: JC
authors.lastname: de Vicente
authors.forename: Sonsoles
authors.initials: S
authors.lastname: Olay
authors.forename: Paloma
authors.initials: P
authors.lastname: Lequerica-Fernandez
authors.forename: Jacobo
authors.initials: J
authors.lastname: Sánchez-Mayoral
authors.forename: Luis Manuel
authors.initials: LM
authors.lastname: Junquera
authors.forename: Manuel Florentino
authors.initials: MF
authors.lastname: Fresno
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D017209:Apoptosis / Q000235:genetics*; D002294:Carcinoma, Squamous Cell / Q000737:chemistry* / Q000235:genetics; D016009:Chi-Square Distribution; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000032:analysis*; D011379:Prognosis; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000032:analysis*; D016019:Survival Analysis; D014062:Tongue Neoplasms / Q000737:chemistry* / Q000235:genetics; D051028:bcl-2-Associated X Protein / Q000032:analysis*
chemical_list: D009363:Neoplasm Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D051028:bcl-2-Associated X Protein