Expression And Clinical Significance Of MTOR And Beclin1 In Papillary Thyroid Carcinoma

Objective:Thyroid tumor is a common and prevalent disease in Department of Head and Neck Surgery,specifically papillary thyroid carcinoma(PTC)which accounts for 80%to 90%.For a few refractory papillary thyroid carcinomas,Traditional surgical resection,radioiodine therapy and TSH inhibition therapy is difficult to achieve satisfactory results.Autophagic death is named type II programmed cell death,the abnormal expression and regulation of autophagy are closely related to tumor,it has become a new focus in the research of tumor targeted therapy.Mammalian rapamycin target protein and autophagy associated protein(Beclin1)are key proteins involved in the development and regulation of autophagy.In this study,we determined the expression of mTOR and Beclin1 in papillary thyroid carcinoma,benign thyroid disease and normal thyroid tissue adjacent to carcinoma to provide the target and theoretical basis for the targeted therapy of papillary thyroid carcinoma.Methods:Immunohistochemical staining was used to detect the expression of mTOR and Beclin1 in 115 cases of papillary thyroid carcinoma、32 cases of benign thyroid diseases(nodular goiter),48 cases of thyroid tissue adjacent to carcinoma,the relationship was analyzed with clinical data.The data were analyzed with SPSS 21.0 software.Results:Immunohistochemical staining showed that the positive rates of mTOR in papillary thyroid carcinoma,nodular goiter and thyroid tissue adjacent to carcinoma were 83%(95/115),41%(13/32),58%(28/48),the difference is statistically significant(P=0.000);The positive rates of Beclin1 in papillary thyroid carcinoma,nodular goiter and thyroid tissue adjacent to carcinoma were 74%(85/115),53%(17/32),46%(22/48),the difference is statistically significant(P=0.001).The positive rates of mTOR and Beclin1have no significant difference between nodular goiter and thyroid tissue adjacent to carcinoma.It was positive correlation between mTOR and Beclin1expression in papillary thyroid carcinoma(r_s=0.459,P=0.000).The difference of mTOR expression among different tumor sizes was statistically significant.The expression of mTOR and Beclin1 in thyroid papillary carcinoma has no significant correlation with other clinical characteristics,such as age,sex,etc.Conclusion:1.mTOR is highly expressed in papillary thyroid carcinoma.2.Beclin1 is highly expressed in papillary thyroid carcinoma.3.The expression of mTOR and Beclin1 in papillary thyroid carcinoma is positively correlated.4.The difference of mTOR expression in papillary thyroid carcinoma is related to the size of the tumor.5.mTOR and Beclin1 may be potential markers for detection of papillary thyroid carcinoma and potential targets for molecular targeting therapy.