Mandatory fortification with folic acid in the United States is not associated with changes in the degree or the pattern of global DNA methylation in cells involved in cervical carcinogenesis.

The purpose of this study was to evaluate whether mandatory fortification of grain products with folic acid in the USA is associated with changes in global DNA methylation in cells involved in cervical carcinogenesis. Archived specimens of cervical intraepithelial neoplasia (CIN) diagnosed before (1990-92) and after mandatory folic acid fortification (2000-02) were used to examine for global DNA methylation in specific lesions involved in cervical carcinogenesis by using a monoclonal antibody specific for 5 methyl cytosine (5-mc). The total number of lesions examined was 152 in the pre-fortification period and 172 in the post-fortification period.

[DNA sperm methylation in assisted reproductive techniques].

In the last few years, many tests were developed to study the fertilizing properties of the spermatozoa. However none of them was useful to obtain a prognostic factor. Indeed, the integrity of the spermatic DNA is also necessary to a successful fertilization for obtaining a pregnancy.

Patterns of global DNA and histone methylation appear to be similar in normal, dysplastic and neoplastic oral epithelium of humans.

Although there is growing interest in the possibility that alterations in histone methylation may play a role in carcinogenesis, it has not been explored adequately in humans. Similarly, there are no reports of associations between this and a similar epigenetic event, DNA methylation. Using immunohistochemical staining, we compared the methylation of DNA and histones in histopathologically normal oral epithelium, dysplastic oral lesions, and squamous cell cancers (SCCs) from subjects with squamous cell cancer (n=48) with those of normal oral epithelium from subjects without oral cancer (n=93) who were matched on age and race.

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.