title: Expression form of p53 and PCNA at the invasive front in oral squamous cell carcinoma: correlation with clinicopathological features and prognosis.
abstract: BACKGROUND
  Abnormalities in cell-cycle-controlling genes are important in the malignant transformation and proliferation of tumors. Among these genes, the tumor suppressor gene p53 is the most notable, and its mutations provide an indicator of tumor progression and prognosis. Proliferating cell nuclear antigen (PCNA) is a highly conserved nuclear protein that is expressed during cell replication and DNA repair. This study examined the expression of p53 and PCNA at the invasive front of oral squamous cell carcinomas (OSCC) by immunohistochemical staining, and investigated the relationship of these proteins to clinicopathological findings and prognosis.
  
  
  METHODS
  Fifty-nine biopsy cases of OSCC were examined by immunohistochemical staining. Clinicopathological data were gathered and patient survival was analyzed.
  
  
  RESULTS
  The p53 labeling index (p53-LI) and PCNA labeling index (PCNA-LI) were examined at the invasive front of the tumors. A high p53-LI (p53+) was observed in 17 of the 59 cases (28.8%) and a high PCNA-LI (PCNA+) was observed in 28 of the 59 cases (47.5%). Among the modes of cancer invasion, many of the p53+/PCNA+ cases could be confirmed as highly invasive cancer (P < 0.05). In addition, the p53+/PCNA+ cases showed a high risk of tumor recurrence compared with the other expression forms, and patients with p53+/PCNA+ had a worse prognosis than those with the other expression forms. High labeling indices of p53 and PCNA are associated with poor prognosis in patients with OSCC.
  
  
  CONCLUSIONS
  We suggest that it is important to investigate the expression of p53 and PCNA at the invasive front of OSCC.
authors.affiliation: Department of Oral and Maxillofacial Surgery, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan. k-koroku@oral.m.kanazawa-u.ac.jp
authors.forename: Koroku
authors.initials: K
authors.lastname: Kato
authors.forename: Shuichi
authors.initials: S
authors.lastname: Kawashiri
authors.forename: Kunio
authors.initials: K
authors.lastname: Yoshizawa
authors.forename: Hiroko
authors.initials: H
authors.lastname: Kitahara
authors.forename: Ayako
authors.initials: A
authors.lastname: Okamune
authors.forename: Shirou
authors.initials: S
authors.lastname: Sugiura
authors.forename: Natsuyo
authors.initials: N
authors.lastname: Noguchi
authors.forename: Etsuhide
authors.initials: E
authors.lastname: Yamamoto
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002294:Carcinoma, Squamous Cell / Q000473:pathology* / Q000556:secondary; D002454:Cell Differentiation / Q000502:physiology; D002467:Cell Nucleus / Q000473:pathology; D004396:Coloring Agents; D005260:Female; D005456:Fluorescent Dyes; D015972:Gene Expression Regulation, Neoplastic / Q000235:genetics; D005887:Gingival Neoplasms / Q000473:pathology; D006801:Humans; D007150:Immunohistochemistry; D008207:Lymphatic Metastasis / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009061:Mouth Mucosa / Q000473:pathology; D009062:Mouth Neoplasms / Q000473:pathology*; D060787:Neoplasm Grading; D009361:Neoplasm Invasiveness; D009364:Neoplasm Recurrence, Local / Q000473:pathology; D009367:Neoplasm Staging; D011379:Prognosis; D018809:Proliferating Cell Nuclear Antigen / Q000032:analysis*; D015996:Survival Rate; D014062:Tongue Neoplasms / Q000473:pathology; D016159:Tumor Suppressor Protein p53 / Q000032:analysis*
chemical_list: D004396:Coloring Agents; D005456:Fluorescent Dyes; D018809:Proliferating Cell Nuclear Antigen; D016159:Tumor Suppressor Protein p53