Human DEK gene on chromosome 6p encodes a 43kD nuclear phospoprotein that was originally identified as part of a fusion protein found in a subset of acute myeloid leukemia carrying a t(6;9) translocation. Although DEK upregulation has been described in a number of human malignancies and was significantly associated with high histologic grade, lymph node metastasis and/or advanced clinical stage, no previous report has evaluated the expression of DEK protein and its clinical significance in oral squamous cell carcinoma (OSCC). Our aims were to determine DEK expression in tissue samples of normal oral mucosa and OSCC by immunohistochemistry, to analyze the correlation between DEK expression and clinicopathological parameters, and to evaluate the value of DEK as a prognostic marker for patient’s survival. Ten normal oral mucosa, 10 epithelial dysplasia, and 60 OSCC samples were studied by immunohistochemistry. DEK expression tended to increase through the full thickness of epithelium in the dysplastic mucosa when compared with those in normal oral mucosa. High expression of DEK protein (score ≥ 2) was found in 68.3% of OSCC cases. Statistical analysis revealed that DEK overexpression in OSCC was positively correlated with high histologic grade (p=0.001), lymph node metastasis (p=0.003), and advanced clinical stage (p=0.039). In the Kaplan-Meier survival analysis, DEK overexpression was significantly associated with decreased overall survival in patients with OSCC (p=0.019). Our results suggest that DEK overexpression may be a reliable marker to predict the clinical outcome in OSCC.

Many researchers have been reported recent trends for rising incidence particularly related to cancer of the tongue in young people. The purpose of this study is to exam the changes of OSCC(oral squamous cell carcinoma) incidence distribution. After Institutional Review Board approval, 1,345cases of OSCC were reviewed from 1993 to 2012 at the department of Oral Pathology at the University of Seoul National Dental Hospital with respect to gender, age, locations. As the results, the most prevalence ages were between 45-69 years old(mean:59.68). There is a noticeable incidence on the eighth decade of life. There are no changes of incidence distribution on se (male:female=69:31) at each year. The most common incidence area was tongue at 1993 but the mandible was the most popular site after 2001. Comparing the incidence rates of the predilection sites over and under 44 years old patients, among patients under 44 years old showed the tongue is the common site steadily. On the other hand, there is a significant increase on the mandible in the over 44 years old patients. In conclusion, this study showed similar results on overall sex distribution and median ages. The trends of locations over 20 years have been increased on the old adult’s mandible. Also, tongue is the common site for the young adults constantly. There are needs for further studies to elucidate the behind etiology. In addition, the true impact of young age on OSCC clinical behavior will remain difficult to determine unless intranational and multi-institutional databases will be combined.