title: Immunohistochemical analysis of p53, APE1, hMSH2 and ERCC1 proteins in actinic cheilitis and lip squamous cell carcinoma.
abstract: OBJECTIVE
  This study has compared the tissue expression of the p53 tumour suppressor protein and DNA repair proteins APE1, hMSH2 and ERCC1 in normal, dysplastic and malignant lip epithelium.
  
  
  RESULTS
  Morphological analysis and immunohistochemistry were performed on archived specimens of normal lip mucosa (n=15), actinic cheilitis (AC) (n=30), and lip squamous cell carcinoma (LSCC) (n=27). AC samples were classified morphologically according to the severity of epithelial dysplasia and risk of malignant transformation. LSCC samples were morphologically staged according to WHO and invasive front grading (IFG) criteria. Differences between groups and morphological stages were determined by bivariate statistical analysis. Progressive increases in the percentage of epithelial cells expressing p53 and APE1 were associated with increases in morphological malignancy from normal lip mucosa to LSCC. There was also a significant reduction in epithelial cells expressing hMSH2 and ERCC1 proteins in the AC and LSCC groups. A higher percentage of malignant cells expressing APE1 was found in samples with an aggressive morphological IFG grade.
  
  
  CONCLUSIONS
  Our data showed that epithelial cells from premalignant to malignant lip disease exhibited changes in the expression of p53, APE1, hMSH2 and ERCC1 proteins; these molecular change might contribute to lip carcinogenesis.
authors.affiliation: Health Science Programme, State University of Montes Claros, Montes Claros, MG, Brazil.
authors.forename: Ludmilla R
authors.initials: LR
authors.lastname: Souza
authors.forename: Thiago
authors.initials: T
authors.lastname: Fonseca-Silva
authors.forename: Camila S
authors.initials: CS
authors.lastname: Pereira
authors.forename: Erivelton P
authors.initials: EP
authors.lastname: Santos
authors.forename: Lucianne C
authors.initials: LC
authors.lastname: Lima
authors.forename: Heloísa A
authors.initials: HA
authors.lastname: Carvalho
authors.forename: Ricardo S
authors.initials: RS
authors.lastname: Gomez
authors.forename: André L S
authors.initials: AL
authors.lastname: Guimarães
authors.forename: Alfredo M B
authors.initials: AM
authors.lastname: De Paula
mesh_terms: D002294:Carcinoma, Squamous Cell / Q000378:metabolism* / Q000473:pathology; D002454:Cell Differentiation; D002613:Cheilitis / Q000378:metabolism / Q000473:pathology; D043603:DNA-(Apurinic or Apyrimidinic Site) Lyase / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000378:metabolism*; D004720:Endonucleases / Q000378:metabolism*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008048:Lip Neoplasms / Q000378:metabolism* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D051718:MutS Homolog 2 Protein / Q000378:metabolism*; D012189:Retrospective Studies; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism*
chemical_list: D004268:DNA-Binding Proteins; D016159:Tumor Suppressor Protein p53; C071447:ERCC1 protein, human; D004720:Endonucleases; C497172:MSH2 protein, human; D051718:MutS Homolog 2 Protein; C085108:APEX1 protein, human; D043603:DNA-(Apurinic or Apyrimidinic Site) Lyase