Cell proliferation activity and the expression of cell cycle regulatory proteins in oral lichen planus.
BACKGROUND
In oral lichen planus (OLP), destruction of the basal cell layer, which is one of the characteristic histological features, is seen and many changes in cell proliferation, cell repair and cell death occur in the injured mucosal epithelium.


METHODS
We studied mucosal tissues from 19 patients of OLP and 10 controls, with immunohistochemistry for Ki-67, p53, cyclin dependent kinase inhibitors (CDKI) and cyclins. Mitotic count was calculated. TUNEL assay was also performed for evaluation of apoptotic cell death.


RESULTS
Mitotic count, Ki-67 and cyclin D1 labeling indices in the basal and parabasal layers of OLP mucosa were elevated in comparison with those of controls. p53, p21Cip1 and TUNEL indices of OLP mucosa were also increased.


CONCLUSIONS
These complex changes, which concomitantly occur in the injured mucosal epithelium, could contribute to the development and maintenance of characteristic mucosal epithelial architectures seen in OLP.
Hirota
Makoto
M
Department of Oral and Maxillofacial Surgery, Yokohama City University School of Medicine, Yokohama, Japan.
Ito
Takaaki
T
Okudela
Koji
K
Kawabe
Ryoichi
R
Yazawa
Takuya
T
Hayashi
Hiroyuki
H
Nakatani
Yukio
Y
Fujita
Kiyohide
K
Kitamura
Hitoshi
H
D000328:Adult; D000368:Aged; D017209:Apoptosis / Q000502:physiology; D015153:Blotting, Western; D018797:Cell Cycle Proteins / Q000032:analysis* / Q000235:genetics; D016923:Cell Death / Q000502:physiology; D002455:Cell Division / Q000502:physiology; D002470:Cell Survival / Q000502:physiology; D019938:Cyclin D1 / Q000032:analysis; D019927:Cyclin E / Q000032:analysis; D050759:Cyclin-Dependent Kinase Inhibitor p21; D050760:Cyclin-Dependent Kinase Inhibitor p27; D018844:Cyclin-Dependent Kinases / Q000037:antagonists & inhibitors; D016213:Cyclins / Q000032:analysis; D004791:Enzyme Inhibitors / Q000032:analysis; D004848:Epithelium / Q000378:metabolism / Q000473:pathology; D005260:Female; D005786:Gene Expression Regulation; D006801:Humans; D007150:Immunohistochemistry; D020287:In Situ Nick-End Labeling; D019394:Ki-67 Antigen / Q000032:analysis; D017676:Lichen Planus, Oral / Q000235:genetics / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D008938:Mitosis; D009061:Mouth Mucosa / Q000378:metabolism / Q000473:pathology; D018709:Statistics, Nonparametric; D016159:Tumor Suppressor Protein p53 / Q000032:analysis; D025521:Tumor Suppressor Proteins / Q000032:analysis
C493956:CDKN1A protein, human; D018797:Cell Cycle Proteins; D019927:Cyclin E; D050759:Cyclin-Dependent Kinase Inhibitor p21; D016213:Cyclins; D004791:Enzyme Inhibitors; D019394:Ki-67 Antigen; D016159:Tumor Suppressor Protein p53; D025521:Tumor Suppressor Proteins; D019938:Cyclin D1; D050760:Cyclin-Dependent Kinase Inhibitor p27; D018844:Cyclin-Dependent Kinases