The Study Of The Inhibitory Effects Of Vitamin E Succinate On Human Tongue Cancer Cell Line Tca8113 Cells

Background:Tongue squamous cell Carcinoma(TSCC) is a serious disease threatening human health. In the oral and maxillofacial carcinoma, its constituent ratio is the highest, the incidence is about 32.3% in our nation, and about between 21% and 52% in Europe and America. In recent years, the incidence tendency ot the tumor shows rising rapidly, especially in the young people, besides, the degree of the malignance is increasing. The carcinoma of the tongue often happens early cervical lymph node metastasis, and the transfering rate is high. Up to now, the comprehensive and sequential therapy is the main therapy for oral and maxillofacial cancers, which revolves around the surgical therapy,radiotherapy and chemotherapeutics methods. The five-year survival rate has been much improved, but the problem of distant metastases and local recurrence has not been completely resolved. In addition, varying degrees of injury and oral deformity after the surgery often cause speech, chewing, swallowing and other important physiological dysfunction, which have serious impact on the patients' quality of life. Therefore, it is necessary to continue the development of chemotherapy treatment which can reduce the distant metastases, decrease localexcision and reduce the side effect.Vitamin E Succinate(VES), an analogue of vitamin E, has growth-inhibitory and induced-apoptosis activity in a wide spectrum of in vitro and in vivo cancer models. VES is noteworthy for its non-toxic and non-inhibitory effects on normal cell types.Up to date, the precise mechanisms of inhibitions are not well understood. Nowadays,the scientists focus on the breast cancer cells,prostate cancer cells and gastric cancercells, etc. As for the the oral cancer cells, it's seldom reported.Objective:To observe the growth inhibition and apoptosis-induced effects of VES orcombined with PYM on human tongue squamous carcinorma Tca8113 cells, and preliminary study the related mechanism of VES or the combination on human tongue squamous carcinorma Tca8113 cells, which can provide theoretical basis for the clinical treatment of tongue cancerMaterials and methods:Tca8113 cells were treated with different concentrations of VES or combined with PYM. The change of morphology was observed under inverted microscope; the effects of growth inhibitory were detected by MTT assay; FAS expression was detected by immuocytochemistry(SABC method) and indirectly immunofluorescene and flow cytometry(FCM); CDK2 expression was detected by immuocytoche -mistry(SABC method); Cell cycle change and apoptotic rates were analyzed by flow cytometry(FCM). The statistical analysis was executed by SPSS. 13.0 and SAS8.2 software, using the chi-square test, chi-square test division, repeated measurement and factorial analysis of variance(ANOVA). Statistically significant level was considered as "alpha equals 0.05".Results:1. The proliferation of Tca8113 cells was inhibited by VES. The effect of growth-inhibition is gradually increasing along with the increasing of concentrations and treated time. The statistical analysis has significant difference between the test groups and the control group (P<0.05). The inhibition curve shows that the effect of growth-inhibition is positive correction with concentrations and treated time. Under inverted microscope, with higher concentrations of VES, the cells' growth and proliferation became slow, floating cells became more and more.2. After treated by VES, the change of cell cycles shows that the ratio of G₁ phase is gradually increasing and the ratio of S phase is decreasing with the increasing of concentration and treated. Statistical graph demonstrated that the changes in G₁ phase and S phase were positively correlated with the concentration and time. The statistical analysis has significant difference between the test groups and the control group (P<0.05).3. After treated by 20μg/ml VES for 48 hours, CDK2 expression of Tca8113 cells decreased and nuclear staining weakened, whereas, the expression of FAS protein increased and the kytoplasm staining enhanced. Proteinum quantitative analysis showes that cell surface FAS expression significantly increased.4. After treated by 10μg/ml,20μg/ml VES for 24 hours and 48 hours, the apoptotic ratio of Tca8113 cells significiantly increased. With the increasing of concentration and treated time, the apoptotic ratio is increasing, which presents significantly relationships of dosage-effect and time-effect, statistically analysis has significant difference (P<0.05). There was a typical apoptotic peak when the cells was treated by 20μg/ml VES after 48 hours.5. When the Tca8113 cells was treated by VES combined with PYM, the growth-inhibition ratio increased significantly. The statistical analysis has significant difference between the test groups and the control group (P<0.05).6. After the Tca8113 cells was treated by VES combined with PYM, the apoptotic ratio was analyzed by flow cytometry. The datas show that the apoptotic ratio of the combination group increased. The statistical analysis has significant difference between the test groups and the control group (P<0.05).Conclusion:1. VES can evidently inhibit the proliferation of the Tca8113 cells, and the effect is positive correlation to the concentrations and treated time.2. VES can change the distribution of the cell cycle. There was evident effect of G1 phase and S phase arrested. It may regulate the expression of CDK2 protein, then causes the cell cycle arrested.3. VES can induce apoptosis in the Tca8113 cells. The mechanism may relate to the up-regulated expression of FAS of the cells.4. VES combined with PYM has significant growth-inhibition and apoptotic induction effect on the Tca8113 cells. VES can enhance the promoting apoptosis ability of the PYM.