HOMEPRODUCTSCOMPANYCONTACTFAQResearchDictionaryPharmaSign Up FREE or Login

8-Nitroguanine formation in oral leukoplakia, a premalignant lesion.

Abstract
Oral leukoplakia is a premalignant lesion associated with development of oral cancer. To clarify the mechanism of development of oral carcinogenesis from leukoplakia, we examined DNA damage in oral epithelium of biopsy specimens of patients with leukoplakia by immunohistochemical methods. Histological changes, such as epithelial dysplasia and infiltration of inflammatory cells were observed in oral tissues of leukoplakia patients. A double immunofluorescence labeling study demonstrated that the accumulation of mutagenic 8-nitroguanine, an indicator of nitrative DNA damage, and 8-oxo-7,8-dihydro-2'-deoxyguanosine, an indicator of oxidative DNA damage, was apparently observed in the oral epithelium of patients with leukoplakia, whereas little or no immunoreactivity was observed in normal oral mucosa. Expression of inducible nitric oxide synthase (iNOS) was also observed in oral epithelium of leukoplakia patients. Immunoreactivity of 3-nitrotyrosine, an indicator of nitrative stress, was observed in oral epithelial cells and colocalized with 8-nitroguanine. Moreover, proliferating cell nuclear antigen and p53 were expressed in 8-nitroguanine-positive epithelial cells in the basal layer. These results suggest that iNOS-mediated nitrative stress contributes to development of oral carcinogenesis from leukoplakia through DNA damage as well as oxidative stress.
AuthorsNing Ma, Toshiro Tagawa, Yusuke Hiraku, Mariko Murata, Xiaohui Ding, Shosuke Kawanishi
JournalNitric oxide : biology and chemistry (Nitric Oxide) Vol. 14 Issue 2 Pg. 137-43 (Mar 2006) ISSN: 1089-8603 [Print] United States
PMID16290060 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
Chemical References
  • 8-nitroguanine
  • Biomarkers, Tumor
  • Proliferating Cell Nuclear Antigen
  • Tumor Suppressor Protein p53
  • 3-nitrotyrosine
  • Tyrosine
  • Guanine
  • 8-Hydroxy-2'-Deoxyguanosine
  • Nitric Oxide Synthase Type II
  • Deoxyguanosine
Topics
  • 8-Hydroxy-2'-Deoxyguanosine
  • Aged
  • Biomarkers, Tumor
  • Deoxyguanosine (analogs & derivatives, biosynthesis)
  • Female
  • Fluorescent Antibody Technique
  • Guanine (analogs & derivatives, biosynthesis)
  • Humans
  • Leukoplakia, Oral (etiology, metabolism, pathology)
  • Male
  • Middle Aged
  • Mouth Mucosa (metabolism, pathology)
  • Nitric Oxide Synthase Type II (metabolism)
  • Oxidative Stress
  • Precancerous Conditions (metabolism, pathology)
  • Proliferating Cell Nuclear Antigen (metabolism)
  • Tumor Suppressor Protein p53 (metabolism)
  • Tyrosine (analogs & derivatives, metabolism)

Join CureHunter, for free Research Interface BASIC access!

Take advantage of free CureHunter research engine access to explore the best drug and treatment options for any disease. Find out why thousands of doctors, pharma researchers and patient activists around the world use CureHunter every day.
Realize the full power of the drug-disease research graph!


Choose Username:
Email:
Password:
Verify Password:
Enter Code Shown: