title: Immunohistochemical staining of Langerhans cells in HPV-positive and HPV-negative cases of oral squamous cells carcinoma.
abstract: The Human Papillomavirus (HPV) has been strongly implicated in development of some cases of oral squamous cell carcinoma (OSCC). However, the immunological system somehow reacts against the presence of this virus. Among the cells involved in such mechanism of defense Langerhans cells (LC) stand out, which are responsible for processing and presenting antigens.
  
  
  OBJECTIVE
  The purposes of this study were to investigate the presence of HPV DNA and to evaluate the immunohistochemical reactivity for Langerhans cells between HPV-positive and HPV-negative OSCC. Twenty-seven cases of OSSC were evaluated.
  
  
  METHODS
  DNA was extracted from paraffin-embedded tissue samples and amplified by Polymerase Chain Reaction (PCR) for the detection of HPV DNA. Viral typing was performed by dot blot hybridization. Immunohistochemistry was performed by the Streptavidin-biotin technique.
  
  
  RESULTS
  From the 27 cases, 9 (33.3%) were HPV-positive and 18 (66.0%) HPV-negative. HPV 18 was the most prevalent viral type (100% cases) and infection with HPV-16 (co-infection) was detected in only 1 case. In the OSCC specimens examined, immunoreactivity to S-100 antibody was detected in all cases, with a mean number of 49.48±30.89 Langerhans cells positive for immunostaining. The mean number of immunostained Langerhans cells was smaller in the HPV-positive cases (38 cells/case) than in the HPV-negative cases (42.5 cells/case), but this difference was not significant (p=0.38).
  
  
  CONCLUSIONS
  The low frequency of detection of HPV DNA in OSCC indicates a possible participation of the virus in the development and progression of only a subgroup of these tumors. There was no association between the immunohistochemical labeling for Langerhans cells (S-100+) and HPV infection of in OSSC. These findings suggest that the presence of HPV in such OSCC cases could not alter the immunological system, particularly the Langerhans cells.
authors.affiliation: School of Dentistry, Federal University of Ceará, Sobral, CE, Brazil.
authors.forename: Karuza Maria Alves
authors.initials: KM
authors.lastname: Pereira
authors.forename: Rosilene Calazans
authors.initials: RC
authors.lastname: Soares
authors.forename: Márcio Campos
authors.initials: MC
authors.lastname: Oliveira
authors.forename: Leão Pereira
authors.initials: LP
authors.lastname: Pinto
authors.forename: Antônio de Lisboa Lopes
authors.initials: Ade L
authors.lastname: Costa
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D052685:Alphapapillomavirus / Q000235:genetics* / Q000276:immunology; D002294:Carcinoma, Squamous Cell / Q000276:immunology / Q000821:virology*; D015342:DNA Probes; D004279:DNA, Viral / Q000302:isolation & purification; D005260:Female; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D007801:Langerhans Cells / Q000276:immunology* / Q000821:virology; D008297:Male; D008875:Middle Aged; D009062:Mouth Neoplasms / Q000276:immunology / Q000821:virology*; D030361:Papillomavirus Infections / Q000821:virology*; D016133:Polymerase Chain Reaction; D013194:Staining and Labeling / Q000379:methods
chemical_list: D015342:DNA Probes; D004279:DNA, Viral