The Expression And Significance Of EZH22and P57^kip2 In Human Tongue Squamous Cell Carcinoma

Background：Tongue squamous cell carcinoma（TSCC） has been one of the most seriousmaxilla-facial diseases threatening human health, and its morbidity is increasing yearby year. The typical clinical characteristic of fast growth rate, deep stromal invasionand strong cervical lymph node metastasis rate were significantly associated withpoor prognosis, if invasion genioglossus can seriously affect the tongue function.Thelatest30years, the5-year survival rate of patients with tumors of the tongue has notimproved significantly which were treated by surgical resection and postoperativecomprehensive treatment. However, the best therapy of the cancer is still unclear.Thus, it is very important to search novel treatment method and research the factorsinvolved in the initiation and the stage of development of tongue cancer to improvethe5-year survival rate.Objective：To investigate the correlation between EZH2and P57^Kip2, clinicopathologicalfeatures and the protein expression of both. To investigate the mechanism of theoccurrence, development and metastasis of TSCCs. To investigate the action and theclinical application in the treatment of EZH2and P57^Kip2in the tongue squamouscarcinoma development of the disease.Methods：The expression of EZH2and P57^Kip2in61cases of paraffin embedded tonguesquamous carcinoma and10cases of normal tissues was measured byimmunohistochemistry using Envision, and the corelation analysis with clinicalfeature of patients was analyzed.Chi-squared statistic was used to analyze statisticalsignificance.Differences were considered statistically significant at p<0.05.Spearman correlation was adopted to analyze the degree and correlation between theexpression of EZH2and P57^Kip2. Results：1. The percentage of EZH2positively expression was up-regulated in TSCCtissues（77%） in comparison with normal tissues （20%）, and statistical difference wasfound between them（P<0.05）.2. The positive expression of P57^Kip2in TSCC tissues（27.9%） was statisticallylower than normal tongue mucosa tissues（100%）（P<0.05）.3. The expression of EZH2and P57^Kip2was correlated to TSCC pathologicalgrades, clinical stages, lymphatic metastasis（P<0.05）, and had no correlation withsex, age, depth of infiltration（P>0.05）.4. In TSCC group, there was negative correlation between the expression ofEZH2and P57^Kip2（Spearman r=-0.704, P<0.01）.Conclusion：1. The expression of EZH2in TSCCs was up-regulated and significant whichinfluenced the malignant degree and prognosis of tongue squamous cell carcicnoma.Thus, EZH2may accelerate the occurrence, development and metastasis of cancer,and play an important part in its transfer course.2. The expression of P57^Kip2significantly decreased in TSCCs compare to thatin normal tongue mucosa tissues, and there is a close correlation to the malignantdegree and prognosis of tongue squamous cell carcicnoma. Absence or decline inP57^Kip2may be associated with the pathogenetic progression and metastasis oftongue squamous cell carcinoma.3. EZH2and P57^Kip2could be regarded as the biological marker that reflectmalignant degree and evaluate prognosis in tongue squamous cell carcinoma, andthey will be a new targeted therapeutic approaches in the research of tumor genetherapy.