title: Immunohistochemical expression of Bax and Bcl-2 in penile carcinoma.
abstract: There is a complex interplay between the pro-apoptotic Bax and anti-apoptotic Bcl-2 family of proteins and the tumor suppressor gene p53. The pathogenic role of Bax and Bcl-2 protein expression in penile carcinomas has not previously been investigated. We examined Bax and Bcl-2 expression in verrucous (VC) and squamous cell carcinoma (SCC) of the penis. Herein we also present a concise review of p53, Bcl-2/Bax ratios, and their relationship to apoptosis. Fourteen cases of penile carcinoma, including 7 VC and 7 well-differentiated SCC, were analyzed for Bax and Bcl-2 expression by immunohistochemical analysis of paraffin embedded archived tissues. The number of positively staining tumor cells was enumerated per 100 tumor cells within non-overlapping high power fields. The Bax immunoreactivity was similar in VC (19+/-3%) and well-differentiated SCC (15+/-4%) (p = 0.69). The expression of Bcl-2 protein was significantly higher in well-differentiated SCC (69+/-12%) compared to VC (36+/-14%) (p = 0.04). The mean Bcl-2/Bax ratio was significantly lower in VC (1.89) compared to well-differentiated SCC (4.6) (p = 0.05). These findings indicate that penile VC and SCC are immunophenotypically distinct. Bax expression is comparable in verrucous and low-grade squamous cell carcinomas, but Bcl-2 expression of Bcl-2 is significantly higher in the squamous cell carcinomas.
authors.affiliation: Department of Pathology, University of South Florida College of Medicine, Tampa, FL 33612, USA. mbkmmorgan@aol.com
authors.forename: Sadia
authors.initials: S
authors.lastname: Saeed
authors.forename: Connie A
authors.initials: CA
authors.lastname: Keehn
authors.forename: Farah K
authors.initials: FK
authors.lastname: Khalil
authors.forename: Michael B
authors.initials: MB
authors.lastname: Morgan
mesh_terms: D002294:Carcinoma, Squamous Cell / Q000473:pathology*; D018289:Carcinoma, Verrucous / Q000473:pathology*; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008499:Medical Records; D010412:Penile Neoplasms / Q000473:pathology*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism*; D051028:bcl-2-Associated X Protein
chemical_list: C494826:BAX protein, human; D019253:Proto-Oncogene Proteins c-bcl-2; D051028:bcl-2-Associated X Protein