Expression of COX-2 and bcl-2 in oral lichen planus lesions and lichenoid reactions.
Oral lichen planus and lichenoid reactions are autoimmune type inflammatory conditions of the oral mucosa with similar clinical and histological characteristics. Recent data suggest that oral lichenoid reactions (OLR) present a greater percentage of malignant transformation than oral lichen planus (OLP).


OBJECTIVE
To compare the expression of bcl-2 and COX-2 in OLP and OLR.


METHODS
The study population consisted of 65 cases; 34 cases diagnosed as OLR and 31 as OLP. A retrospective study was done, and bcl-2 and COX-2 expression was semiquantitatively analysed.


RESULTS
Fifty-three per cent (18/34) of the ORL samples tested positive for COX-2, whereas in the OLP group, 81% of the samples (25/31) immunostained positive for COX-2. The Fisher's exact test for the expression of COX-2 revealed that there are significant differences between the two groups, P = 0.035. With respect to the expression of the bcl-2 protein, 76% (26/34) of the samples were positive in OLR, while 97% (30/31) were positive in the group with OLP. The Fisher's exact test for the expression of bcl-2 revealed that there are significant statistical differences between the two groups, P = 0.028.


CONCLUSIONS
The expression of bcl-2 and COX-2 was more commonly expressed in OLP when compared with OLR.
Dental Therapeutics, School of Dentistry, Central University of Venezuela, Caracas 1051, Venezuela.
Alven J
AJ
Arreaza
`Raúl Vincentelli' Oral Pathology Laboratory, Institute of Dental Research, School of Dentistry, Central University of Venezuela, Caracas 1051, Venezuela.
Helen
H
Rivera
`Raúl Vincentelli' Institute of Dental Research, School of Dentistry, Central University of Venezuela, Caracas 1051, Venezuela.
María
M
Correnti
COX-2; bcl-2; lichenoid reaction; oral lichen planus