The correlation between p16 expression and INK4a locus mutation with grades and stages in oral squamous cell carcinoma.

Objective: p16INK4a is a tumor suppressor gene playing a critical role. Researches have indicated the gene to be altered in oral squamous cell carcinoma. Present studies have tried to assess the correlation between p16INK4a expression and INK4a locus mutation in relation to grades and stages of this tumor. Materials and Methods: Expression of p16INK4a was studied immunohistochemically in 58 oral squamous sell carcinoma samples and INK4a locus mutation was determined by polymerase chain reaction (PCR) and conformation sensitive gel electrophoresis (CSGE). Results: Expression of p16INK4a was higher in stage1 compared to stage 2, 3, and 4 (P = 0.234). The difference was not signifi cant in grade 1, 2, and 3 (P = 0.671). The average values of total score (TS) were signifi cantly higher in stage1 compared to stage 2, 3, and 4 (P = 0.035). The average values of complete score (CS) were higher in stage 1 compared to stage 2, 3, and 4 (P = 0.061). The research did not show a signifi cant correlation between lymph node involvement and p16INK4a expression (P = 0.491). It seems that 5.1% (3/58) of samples have mutation in INK4a locus. Conclusion: Loss of p16INK4a expression occurred in initial stages of oral squamous cell carcinoma. Evaluation of TS and CS for p16INK4a might be a useful clinical indicator concerning the tumor. However, gene mutation is believed to have minor rate of genetic alteration in carcinogenesis.

Micronucleus assay of buccal mucosa cells in smokers with the history of smoking less and more than 10 years.

Introduction and Aim: Cigarette smoking causes severe health problems such as cancer. Micronuclei are structures that present after genomic damages to the cells. The present study is aimed at evaluating the micronucleus assay of buccal mucosa cells in smokers who smoked less or more than 10 years. Materials and Methods: The present study has been a historical cohort study. The smokers were divided into two groups: First group include individuals with a smoking history less than 10 years (14 samples) and second group with the smoking history of more than 10 years (26 samples).The control group consisted of nonsmokers (23 samples). The exfoliated buccal mucosa cells were scrapped using spatula and were spread over the glass slide. Feulgen method was used for micronucleus staining. 500 cells per subjects were counted. The presence of micronucleus in all subjects and the mean percentage of micronucleus in nuclei were determined. Data were subjected to statistical analysis using T-test. Results: The mean number of micronucleus of buccal mucosa cells in nonsmokers, first group (smoking history less than 10 years) and second group (smoking history more than 10 years) was 0.94 ± 0.94, 1.89 ± 0.62 and 2.01 ± 0.93 respectively. The difference was statistically significant (P < 0.002). Considering the number of micronuclei of the buccal mucosa cells, the difference between groups 1 and 2 was not significant (P < 0.6). The mean percentage of micronucleated cells in nonsmokers, group 1 and group 2 was 2.26 ± 2.17%, 13.9 ± 5.90 and14.3 ± 7.97, respectively. The difference was statistically significant (P < 0.001).The difference between the percentage of the cells with micronucleus in smokers with a smoking history of less or more than 10 years was not significant (P < 0.6). Conclusion: The mean number of micronuclei in buccal mucosa cells of the nonsmokers was significantly lower than that of the smokers. However, the mean number of micronucleus of buccal mucosa cells in smokers who smoked more than 10 years was higher than smokers who smoked less than 10 years. Increasing the smoking duration could heighten the frequency of micronucleus; however, the difference was not significant.

Incontinentia pigmenti.

Incontinentia pigmenti (IP) or Bloch-Sulzberger syndrome is a rare X-linked dominant genodermatosis related to the NF kappa B essential modulator (NEMO) gene with approximately 800 cases reported worldwide. It usually occurs in females characterized by cutaneous, skeletal, neurological, ocular and dental abnormalities as well as an increased risk of childhood malignancies. Herein, we report a case of IP in a 14-year-old girl emphasizing early diagnosis and adding to the current literature on the subject.