title: The correlations between alteration of p16 gene and clinicopathological factors and prognosis in squamous cell carcinomas of the buccal mucosa.
abstract: OBJECTIVE
  To evaluate relationships between the alteration of p16 gene and the clinical status and prognosis of the patients with squamous cell carcinoma of the buccal mucosa.
  
  
  METHODS
  Thirty buccal cancers were included in the analysis. Deletion analysis was performed by PCR. Point mutation analysis was used by PCR-SSCP and direct sequencing. Methylation-specific PCR methods were adopted for the evaluation of p16 methylation. The correlation between alteration of p16 gene and clinicopathological factors buccal cancer was evaluated by Fisher's exact test. Kaplan-Meier and Cox regression were used to investigate the relationship between p16 alteration and survival time.
  
  
  RESULTS
  The frequency of p16 alteration was 63.3% in buccal carcinomas. P16 deletion was associated significantly with tumor size (P = 0.01). P16 point mutation was associated significantly with differentiation (P = 0.006). P16 methylation was associated significantly with nodes metastasis (P = 0.027). The overall survival rate of 30 buccal carcinomas was 53.3%. The Log-rank test (P = 0.021) and univariate Cox regression analysis (P = 0.030) revealed that p16 methylation was significantly associated with the overall survival rate. Multivariate analysis showed that p16 deletion, p16 mutation, and p16 methylation were not statistically significant.
  
  
  CONCLUSIONS
  The alterations of p16 gene may play a major role in malignancy and development and metastases of buccal carcinoma and may be an excellent marker of aggressive clinical behavior. P16 methylation has a prognostic value in buccal carcinoma but not an independent prognosis factor. P16 point mutation and p16 deletion have not prognostic significance in buccal carcinoma.
authors.affiliation: Department of Oral and Maxillofacial Surgery, School of Stomatology, Hebei Medical University, Shijiazhuang, Hebei, China.
authors.forename: Yuying
authors.initials: Y
authors.lastname: Dong
authors.forename: Jie
authors.initials: J
authors.lastname: Wang
authors.forename: Fusheng
authors.initials: F
authors.lastname: Dong
authors.forename: Xu
authors.initials: X
authors.lastname: Wang
authors.forename: Yinghuai
authors.initials: Y
authors.lastname: Zhang
mesh_terms: D000328:Adult; D000368:Aged; D002294:Carcinoma, Squamous Cell / Q000235:genetics* / Q000473:pathology / Q000556:secondary; D002454:Cell Differentiation / Q000235:genetics; D002467:Cell Nucleus / Q000648:ultrastructure; D003593:Cytoplasm / Q000648:ultrastructure; D019175:DNA Methylation; D005091:Exons / Q000235:genetics; D005260:Female; D005500:Follow-Up Studies; D017353:Gene Deletion; D019942:Genes, p16; D006720:Homozygote; D006801:Humans; D008207:Lymphatic Metastasis / Q000235:genetics / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009061:Mouth Mucosa / Q000473:pathology*; D009062:Mouth Neoplasms / Q000235:genetics* / Q000473:pathology; D009367:Neoplasm Staging; D017354:Point Mutation / Q000235:genetics; D018807:Polymorphism, Single-Stranded Conformational / Q000235:genetics; D011379:Prognosis; D011401:Promoter Regions, Genetic / Q000235:genetics; D017422:Sequence Analysis, DNA; D015996:Survival Rate