Pattern of nonspecific (or global) DNA methylation in oral carcinogenesis.
BACKGROUND
Although alterations in nonspecific (or global) DNA methylation (GDM) in specific cells are known to be involved in the process of lung carcinogenesis, similar associations have not been evaluated in other smoking-related cancers of the head and neck.


METHODS
We evaluated the status of GDM by using monoclonal antibodies specific for 5-methylcytosine (5-mc) in oral squamous cell carcinoma (SCC) specimens of 48 cigarette smokers who had SCC develop and in 93 age-, race-, and sex-matched smokers who did not.


RESULTS
Percentages of cells positive for 5-mc immunostaining of DNA of SCC and dysplastic lesions were significantly higher than those of normal oral epithelial cells from cancer subjects and from noncancer subjects. The degree of DNA methylation was unrelated to DNA content.


CONCLUSIONS
The pattern of GDM in oral SCCs is different from that of lung SCCs. The differences in nutrient risk factor profiles that are related to GDM and differential activity of DNA methyltranferases between oral and lung SCCs may explain these observations.
Piyathilake
Chandrika J
CJ
Department of Nutrition Sciences, Division of Nutritional Biochemistry and Molecular Biology, University of Alabama at Birmingham, University Station, Birmingham, AL 35294, USA. piyathic@uab.edu
Bell
Walter C
WC
Jones
Jennifer
J
Henao
Olga L
OL
Heimburger
Douglas C
DC
Niveleau
Alain
A
Grizzle
William E
WE
D044503:5-Methylcytosine / Q000276:immunology; D000911:Antibodies, Monoclonal / Q000276:immunology; D002294:Carcinoma, Squamous Cell / Q000235:genetics* / Q000473:pathology; D016022:Case-Control Studies; D019175:DNA Methylation; D004848:Epithelium / Q000473:pathology; D006801:Humans; D007150:Immunohistochemistry; D009061:Mouth Mucosa / Q000473:pathology; D009062:Mouth Neoplasms / Q000235:genetics* / Q000473:pathology; D011230:Precancerous Conditions / Q000235:genetics / Q000473:pathology; D012907:Smoking / Q000453:epidemiology
D000911:Antibodies, Monoclonal; D044503:5-Methylcytosine