title: Relationship between the epithelial expression of hMLH1, MDM2, and p63 and lower lip carcinogenesis.
abstract: OBJECTIVE
  To evaluate the relationship between the epithelial expression of hMLH1, MDM2, and p63 in lower lip carcinogenesis, comparing the immunostaining of these proteins in cases of actinic cheilitis (AC) and lower lip squamous cell carcinoma (SCC).
  
  
  METHODS
  Forty cases of AC and 40 cases of SCC were studied, both lesions were of lower lip. Histological sections of 3 μm were submitted to immunoperoxidase method, and 1000 cells were counted for immunohistochemical analysis of lesions. The results were analyzed quantitatively, and expression was compared by the Mann-Whitney, Student t-test, or one-way ANOVA, adopting a level of significance of 5%.
  
  
  RESULTS
  A higher percentage of epithelial cells expressing hMLH1 was observed in cases of AC without dysplasia or mild dysplasia (721.23 ± 88.116), whereas fewer positive cells were observed in lower lip SSCs (255.03 ± 199.47) when compared to the AC group (P < 0.001). Immunoexpression of MDM2 was higher in SCCs of the lower lip compared with AC (P = 0.019). For p63 protein, the expression was higher in AC than in SCC (P = 0.045).
  
  
  CONCLUSIONS
  The present results showed changes in the immunoexpression of hMLH1, MDM2, and p63 in epithelial cells from premalignant and malignant lip disease, supporting the hypothesis that these alterations are related to the process of lower lip carcinogenesis.
authors: Oral Pathology, Federal University of Rio Grande do Norte, Natal, RN, Brazil.
authors: Denise Hélen Imaculada Pereira
authors: DH
authors: de Oliveira
authors: Maria Luiza Diniz
authors: ML
authors: de Sousa Lopes
authors: Dmitry José
authors: DJ
authors: de Santana Sarmento
authors: Lélia Maria Guedes
authors: LM
authors: Queiroz
authors: Márcia Cristina
authors: MC
authors: da Costa Miguel
authors: Ericka Janine Dantas
authors: EJ
authors: da Silveira
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000032:analysis*; D063646:Carcinogenesis; D002294:Carcinoma, Squamous Cell / Q000737:chemistry / Q000473:pathology; D002613:Cheilitis / Q000378:metabolism / Q000473:pathology; D045643:DNA Repair Enzymes / Q000032:analysis*; D004847:Epithelial Cells / Q000737:chemistry / Q000473:pathology; D005260:Female; D006801:Humans; D008046:Lip / Q000737:chemistry* / Q000473:pathology; D008048:Lip Neoplasms / Q000737:chemistry* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009061:Mouth Mucosa / Q000737:chemistry / Q000473:pathology; D000070957:MutL Protein Homolog 1; D060787:Neoplasm Grading; D009687:Nuclear Proteins / Q000032:analysis*; D011230:Precancerous Conditions / Q000737:chemistry / Q000473:pathology; D051736:Proto-Oncogene Proteins c-mdm2 / Q000032:analysis*; D012189:Retrospective Studies; D014157:Transcription Factors / Q000032:analysis*; D025521:Tumor Suppressor Proteins / Q000032:analysis*
chemical_list: D048868:Adaptor Proteins, Signal Transducing; C501486:MLH1 protein, human; D009687:Nuclear Proteins; C115051:TP63 protein, human; D014157:Transcription Factors; D025521:Tumor Suppressor Proteins; C497206:MDM2 protein, human; D051736:Proto-Oncogene Proteins c-mdm2; D000070957:MutL Protein Homolog 1; D045643:DNA Repair Enzymes
keywords: cheilitis; lip neoplasm; oral cancer; squamous cell carcinoma