ABSTRACT
Background: Oxidative stress is involved in the pathogenesis of various lifestyle-related diseases, including malignancies. The body naturally produces antioxidants as a means of defending itself against these free radicals which neutralize them, thereby rendering them harmless to other cells. There is a close relation between oxidative stress and all aspects of cancer, from carcinogenesis to the tumor-bearing state, from treatment to its prevention. Aim: The present study was aimed to estimate the plasma levels of antioxidant enzymes and molecules in cases of oral lesion patients. Study Design and Methodology: A case control study was designed in Amity Institute of Biotechnology, Amity University Uttar Pradesh, Lucknow campus. A total of fifty histopathologically proven oral lesion cases (leukoplakia, erythroplakia, lichen planus and oral submucous fibrosis patients) were taken for the study. Their blood samples were collected and plasma was subjected to evaluation of oxidative stress markers. Control group consisted of equal number of healthy subjects. The data is expressed as mean±SD. Student -t test was applied for significance of the biochemical parameters. Results: The results have demonstrated that levels of catalase, myeloperoxidase, reduced glutathione glutathione reductase and glutathione peroxidase are decreased whereas those of malondialdehyde and nitric oxide have increased in the oral lesions patient group as compared to controls. Conclusion: Oxidative stress has been shown to be an important indicator in case of oral cancer. Similar findings in pre-malignant oral lesions can be correlated in establishing the role of oxidative stress in initiation and conversion of premalignant lesions into malignant ones.
ABSTRACT
Genomic DNA methylation is one of the most important epigenetic modifications in eukaryotes play vital role in development of severe disease like cancer. Many techniques used for assessment of DNA methylation, bisulfite treatment followed by methylation specific polymerase reaction (MSP) are one of them, which introduce conversion of unmethylated cytosine into uracil. The significant level of bisulfite treated DNA degradation results in the failure of methylation detection. Therefore, this step is to be properly controlled to avoid the degradation of DNA. In the present study, an attempt has been made to access the incubation time of DNA with bisulfate treatment at three time points i.e. 2.5, 4 and 16 hrs to get complete conversion of cytosine to uracil. Currently, the experiments were undertaken using oral cancer tissue, with varying incubation time of bisulfite treatment and 2 representative genes viz MGMT and p16 were selected for the quantitative assessment of methylation by real time PCR. Both genes are frequently methylated at promoter region in carcinogenesis. The short term incubation for 4hrs indicated better real time threshold value for p16 and MGMT gene methylation (Ct 25.55, 27.25) and unmethylation (Ct 18.82, 25.84) in tissue whereas it was 28.16, 37.35 and 21.98, 26.19 in blood sample, respectively as compared to other incubation time which shows less degradation of full length DNA.