[The expression of apoptosis-associated proteins Bcl-2, Bax in oral leukoplakia and lichen planus].
OBJECTIVE
The purpose of this study was to explore the pathogenesis and carcinogenesis of oral leukoplakia (LK) and oral lichen planus (OLP) by examining the expression of apoptosis-associated proteins Bcl-2 Bax in LK and OLP.


METHODS
The expression of Bcl-2 and Bax were measured in 10 cases of normal oral mucosa,18 cases of OLP, 23 cases of LK and 22 cases of oral squamous cell carcinoma (SCC) by immunohistochemical assays.


RESULTS
In the epithelial cell layer of LK and OLP, the positive Bcl-2 expression was similar to oral normal mucosa,but in the part of the lymphocytic infiltration of OLP, overexpression of Bcl-2 was observed. In the SCC, the Bcl-2 expression was significantly higher than that in normal oral mucosa(P<0.05). In the tissue of simple hyperplasia, mild dysplasia, moderate dysplasia, poorly differentiated SCC and erosive OLP, the expression of Bax was significantly higher than that in normal oral mucosa (P<0.05).


CONCLUSIONS
Bax was closely related to the early event of LK carcinogenesis. Bcl-2 may not play a role in LK carcinogenesis. Bcl-2 and Bax play an important role in pathogenesis of OLP. We postulate that the Bcl-2 inhibits the apoptosis of lymphocytes that strengthen the cell-mediated immune process and the overexpression of Bax was related to the apoptosis of epithelial cells in OLP.
Fan
Yuan
Y
Basic Medical College of Nanjing, University of Traditional Chinese Medicine, Nanjing 210029, China. fanyuan65@hotmail.com
Zhan
Zhen
Z
Peng
Tao
T
Song
Xiao-ling
XL
Feng
Zhen-qing
ZQ
D017209:Apoptosis; D002294:Carcinoma, Squamous Cell / Q000378:metabolism; D006801:Humans; D007972:Leukoplakia, Oral / Q000453:epidemiology / Q000378:metabolism*; D017676:Lichen Planus, Oral / Q000453:epidemiology / Q000378:metabolism*; D009061:Mouth Mucosa / Q000378:metabolism; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism*; D051028:bcl-2-Associated X Protein / Q000378:metabolism*
D019253:Proto-Oncogene Proteins c-bcl-2; D051028:bcl-2-Associated X Protein