Tobacco and inflammation effects in immunoexpression of hMSH2 and hMLH1 in epithelium of oral mucosa.
BACKGROUND
Both hMSH2 and hMLH1 are integrated in the DNA mismatch repair (MMR) system. Reduced expression of these proteins has been reported in head and neck carcinoma; however, few studies have examined the normal levels of these proteins in oral tissues or investigated factors which could interfere with this expression. The aim of this study was to detect the expression pattern of hMSH2 and hMLH1 in normal oral mucosa and to correlate this with demographic data, smoking and local inflammation.


METHODS
The expression of hMSH2 and hMLH1 was evaluated in 38 samples of normal mucosa epithelium using immunohistochemistry.


RESULTS
No relationship was observed between hMSH2 and hMLH1 and demographic data. The hMLH1 but not hMSH2 expression was altered in smokers and in the presence of inflammation.


CONCLUSIONS
Both hMSH2 and hMLH1 are highly expressed in the normal epithelium of oral mucosa. In addition, hMLH1 expression is directly influenced by tobacco use and inflammation.
Fernandes
Anacélia Mendes
AM
Department of Oral Pathology and Surgery, School of Dentistry, Universidade Federal de Minas Gerais, Brazil.
De Souza
Vânia Ribeiro da Cunha
VR
Springer
Cornelis Robert Araújo
CR
Cardoso
Sérgio Vitorino
SV
Loyola
Adriano Mota
AM
Mesquita
Ricardo Alves
RA
Aguiar
Maria Cássia Ferreira
MC
D048868:Adaptor Proteins, Signal Transducing / Q000096:biosynthesis*; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D009061:Mouth Mucosa / Q000378:metabolism*; D000070957:MutL Protein Homolog 1; D051718:MutS Homolog 2 Protein / Q000096:biosynthesis*; D009687:Nuclear Proteins / Q000096:biosynthesis*; D012907:Smoking / Q000378:metabolism*; D013280:Stomatitis / Q000378:metabolism
D048868:Adaptor Proteins, Signal Transducing; C501486:MLH1 protein, human; D009687:Nuclear Proteins; C497172:MSH2 protein, human; D000070957:MutL Protein Homolog 1; D051718:MutS Homolog 2 Protein