title: Immunohistochemical assessment of proliferating cell nuclear antigen protein expression in plaque, reticular and erosive types of oral lichen planus.
abstract: BACKGROUND
  Proliferating cell nuclear antigen (PCNA) is a nuclear protein synthesized in the late G1 and S-phase of the cell cycle. Immunodetection of this protein represents a useful marker of the proliferation status of lesions.
  
  
  OBJECTIVE
  The aim of this study is to evaluate the immunohistochemical expression of PCNA in oral lichen planus (OLP) and to assess the PCNA expression in a different layer of epithelium in different types of OLP.
  
  
  METHODS
  A total of 96 cases of histologically proven OLP, 32 cases each of erosive, reticular and plaque type were selected. Two sections were taken from each one for H and E. Other sections were stained according to super sensitive polymer horseradish peroxidase method for identifying PCNA expression.
  
  
  RESULTS
  Of the three types of OLP, erosive type showed higher expression of PCNA (average 66.8%, minimum of 55% and maximum of 80.3%) followed by reticular (average 37.7%, minimum of 26% and maximum of 47%) and plaque type (average 17%, minimum of 5% and maximum of 25%) indicating increased proliferative activity. The erosive type also showed higher expression of PCNA in all the layers of epithelium followed by reticular and plaque type.
  
  
  CONCLUSIONS
  PCNA is a good marker to indicate proliferation status of disease. Out of three types, erosive type possess more proliferative ratio, chances of malignant changes is more in this type.
authors.affiliation: Department of Oral Pathology and Microbiology, School of Dental Sciences, Krishna Institute of Medical Sciences, Deemed University, Karad, Satara, Maharashtra, India.
authors.forename: Rc
authors.initials: R
authors.lastname: Pramod
authors.affiliation: Department of Oral Pathology and Microbiology, A J Institute of Dental Sciences, Mangalore, Karnataka, India.
authors.forename: S
authors.initials: S
authors.lastname: Pandit
authors.affiliation: Department of Oral Pathology and Microbiology, A J Institute of Dental Sciences, Mangalore, Karnataka, India.
authors.forename: D
authors.initials: D
authors.lastname: Desai
authors.affiliation: Department of Oral Medicine and Radiology, School of Dental Sciences, Krishna Institute of Medical Sciences, Deemed University, Karad, Satara, Maharashtra, India.
authors.forename: Kv
authors.initials: K
authors.lastname: Suresh
authors.affiliation: Department of Oral Pathology and Microbiology, A J Institute of Dental Sciences, Mangalore, Karnataka, India.
authors.forename: Ps
authors.initials: P
authors.lastname: Ingaleshwar
authors.affiliation: Department of Oral Pathology and Microbiology, A J Institute of Dental Sciences, Mangalore, Karnataka, India.
authors.forename: Sj
authors.initials: S
authors.lastname: Shetty
authors.affiliation: Department of Oral Pathology and Microbiology, KMCT Dental College, Calicut, Kerala, India.
authors.forename: S
authors.initials: S
authors.lastname: Ahamad
keywords: Immunohistochemistry; Oral lichen planus; Proliferating cell nuclear antigen