Assessing extent of single stranded DNA damage in oral mucosal cells of patients with oral squamous cell carcinoma and its correlation with TNM staging.

Context: This study was carried out on the assumption that oral mucosal cells might show DNA damage in oral squamous cell carcinoma (OSCC). Aims: To evaluate the extent of DNA damage in oral smears of patients with OSCC and determine correlation if any of the extent of DNA damage to TNM staging of oral cancer. Settings and design: A randomized controlled study at a regional cancer centre was designed for this project. Smears were taken from lesion proper of 30 patients with OSCC and from the buccal mucosa of 30 normal healthy volunteers. Materials and methods: Collected cells were centrifuged and single-cell gel electrophoresis (SCGE) assay was performed. DNA damage was visualized under a fluorescent microscope. Statistical analysis used : Mean DNA damage levels of both the groups were measured and statistically analyzed with students' test. The extent of DNA damage was correlated with the TNM stages by employing the one way ANOVA 'F' technique. Results: High statistical significance (P < 0.0001) was found in DNA damage levels between control and study groups. A stepwise increase in DNA damage levels with high statistical significance (P < 0.005) was also found between all the TNM stages. Conclusions: Statistically significant increased DNA damage levels in OSCC patients and their correlation to clinical staging suggest that comet assay may be used effectively to assess the prognosis of OSCC.

Deoxyribonucleic acid damage study in primary amenorrhea by comet assay and karyotyping.

AIM: This study aims at evaluating the chromosomal abnormalities and deoxyribonucleic acid (DNA) damage in cases with primary amenorrhea by karyotyping and comet assay. STUDY DESIGN: A total of 30 cases of primary amenorrhea were recruited. Secondary sexual characters were assessed by Tanner staging. Chromosomal analysis was performed by conventional phytohemagglutinin stimulated lymphocyte cell culture technique. Alkaline version of comet assay was used to evaluate DNA damage. RESULTS: The chromosomal pattern of 20 subjects (66.7%) was found to be normal (46,XX). Two subjects had 46,XY pattern and eight subjects had Turner syndrome (45,X or 45,X/46,XX). The comet parameters were found to be increased among subjects with 45,X monosomy, when compared to the rest of the study group and also in subjects with Tanner stage 1 when compared to stage 2. CONCLUSION: Comet assay revealed increased DNA damage in cases with 45,X monosomy, compared with subjects with 46,XX and 46,XY karyotype, which correlated with clinical features.