Study of P21 Expression in Oral Lichen Planus and Oral Squamous Cell Carcinoma by Immunohistochemical Technique.
BACKGROUND
Lichen planus is a mucocutaneous disease that is relatively common in middle aged individuals. Some studies have shown that oral lichen planus has a potential to progress to squamous cell carcinoma.p21 is a cyclin-dependent kinase inhibitor that regulates the cell cycle, thus it acts as an inhibitor in cell proliferation.


OBJECTIVE
This study was aimed to evaluate and compare the immunostaining of p21 (as a proliferation inhibitory factor) in oral lichen planus (OLP) and oral squamous cell carcinoma (OSCC).


METHODS
In this descriptive cross-sectional study, p21expression was investigated in 24 samples of oral lichen planus (OLP), 24 samples of oral squamous cell carcinoma (OSCC) and 24 samples of oral epithelial hyperplasia (OEH) by employing immunohistochemical staining.


RESULTS
The mean percentage of p21-positive cells in OSCC (54.5±6.6) was significantly higher than that in OLP (32.8±6.08) and OEH (9.4±3.8). Moreover, OLP samples expressed p21 significantly higher than the OEH. Kruskal Wallis test revealed a statistically significant difference between the groups regarding the intensity of staining (p< 0.001).


CONCLUSIONS
According to the findings of this study, the expression of p21 might be related to the potential carcinogenic transformation of lichen planus to SCC. Therefore, continuous follow-up periods for OLP are recommended for diagnosis of the malignant transformations in early stages.
Dept. of Oral and Maxillofacial Pathology, School of Dentistry, Hamadan University of Medical Sciences, Hamadan, Iran.
Fahimeh
F
Baghaei
Dept. of Oral and Maxillofacial Pathology, School of Dentistry, Hamadan University of Medical Sciences, Hamadan, Iran.
Setareh
S
Shojaei
Dept. of Pathology, Schools of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran.
Noushin
N
Afshar-Moghaddam
Dental Research Center, Dept. of Oral Maxillofacial Pathology, School of Dentistry, Hamadan University of Medical Sciences, Hamadan, Iran.
Massoumeh
M
Zargaran
Dept. of Oral and Maxillofacial Pathology, School of Dentistry, Kurdestan University of Medical Sciences, Sanandaj, Iran.
Verisheh
V
Rastin
Dept. of Pathology, Alzahra Hospital, Isfahan University of Medical Sciences, Isfahan, Iran.
Mohsen
M
Nasr
Dept. of Biostatistics and Epidemiology, School of Public Health, Hamadan University of Medical Sciences, Hamadan, Iran.
Abbas
A
Moghimbeigi
Oral lichen planus; Oral squamous cell carcinoma; P21