The Expression And Significance Of TSHR、BRAF And NDRG2 In Papillary Thyroid Carcinomar

Objective:Thyroid cancer has the highest incidence in head and neck malignant tumors.Comparing with the current pathological types,thyroid cancer can be divided into four types:papillary adenocarcinoma,follicular adenocarcinoma,medullary carcinoma and undifferentiated carcinoma.Among the pathological types of thyroid cancer,papillary adenocarcinoma is the most common one.The malignant degree is much lower.It is found that about 80%of thyroid cancer patients suffer from papillary adenocarcinoma^[1-2].Studies have shown that the incidence of papillary adenocarcinoma is gradually increasing in recent years,of which most patients are aged between20 and 40 years old.Therefore,we can not ignore its harm to human health^[3].At present,the treatment of papillary thyroid adenocarcinoma is mainly symptomatic treatment.The surgical treatment,as well as endocrine therapy and radioactive ¹³¹I treatment are commonly applied.Thyrotropin receptor（TSHR）plays an important role in the regulation of thyroid function.The combination of TSH and TSHR can promote the synthesis and secretion of thyroid hormone and the growth of thyroid cells.At the same time,the iodine uptake rate of thyroid cancer cells can be increased through the synthesis of sodium/iodine transporter.BRAF gene is an important member of RAF gene family and plays an important role in RAS-RAF-MEK/ERK signal transduction pathway.BRAF mutation is relatively high in thyroid papillary adenocarcinoma.The occurrence and developments of thyroid papillary adenocarcinoma are closely related to this mutation.In recent years,a new candidate tumor suppressor gene NDRG2 has been found,which is low or not expressed in many malignant tumors or cell lines.At the same time,it is related to the malignancy and prognosis of some malignant tumors.The expression of NDRG2 can inhibit the proliferation and invasion of some malignant tumors.The purpose of this paper is to explore the correlation of TSHR,BRAF and NDRG2 expression in thyroid papillary adenocarcinoma and nodular goiter,and provide theoretical basis for the occurrence and development of thyroid papillary adenocarcinoma,judgment and evaluation of its prognosis and therapeutic effect.Methods:A total of 55 specimens of thyroid papillary adenocarcinoma were selected from The Fourth Hospital of Hebei Medical University from October 2017 to April 2018,and 40 specimens of nodular goiter were taken as control group.The expression of TSHR,BRAF and NDRG2 in thyroid papillary adenocarcinoma（PTC group）and nodular goiter（control group）were detected with immunohistochemistry（IHC）S-P method.SPSS19.0 software was used to conduct statistical analysis.P≤0.05indicates significant difference,P≤0.01 indicates very significant difference.Result:1.The expression of TSHRImmunohistochemical results showed that TSHR was expressed in PTC group and control group,and there was no significant difference between the 2groups（P>0.05）.The expression of TSHR was correlated with clinical stage（P<0.01）and lymph node metastasis（P<0.01）,but not with tumor size,age and sex（P>0.05）.2.The expression of BRAFImmunohistochemical results indicated that the positive expression of BRAF in PTC group was significantly higher than that in control group（P<0.01）.The expression of BRAF was correlated with clinical stage（P<0.05）,but not with lymph node metastasis,tumor size,age and sex（P>0.05）.3.The expression of NDRG2Immunohistochemical results suggested that the expression of NDRG2 in PTC group was significantly lower than that in control group（P<0.01）.The expression of NDRG2 was correlated with clinical stage（P<0.01）and lymph node metastasis（P<0.05）,but not with tumor size,age and sex（P>0.05）.4.The correlation analysis of TSHR,BRAF and NDRG2 protein expression in PTCThe expression of BRAF was positively correlated with the expression of TSHR in papillary thyroid carcinoma（P=0.000,r=0.264）.Namely,the expression of TSHR decreased with the decrease of BRAF expression in thyroid papillary carcinoma.The expression of NDRG2 was negatively correlated with the expression of BRAF in papillary thyroid carcinoma（P=0.000,r=-0.015）.That is,the expression of BRAF increases with the decrease of NDRG2 expression in cancer tissues.Conclusion:1.TSHR,BRAF and NDRG2 proteins were all expressed in PTC tissues and nodular goiter tissues.2.The expression of TSHR protein in PTC tissues was not significantly different from that in nodular goiter tissues.The expression of TSHR in PTC was correlated with clinical stage and lymph node metastasis,but not with tumor size,age and sex.It is suggested that TSHR may be related to invasion and metastasis of PTC and can be used as a reference index for prognosis evaluation.3.The expression of BRAF protein in PTC tissues was significantly higher than that in nodular goiter tissues.The expression of BRAF in PTC was related to clinical stage,but not to lymph node metastasis,tumor size,age and sex.It is suggested that BRAF plays an important role in the occurrence and development of PTC and can be used as an important prognostic indicator.4.The expression of NDRG2 protein in PTC tissues was significantly lower than that in nodular goiter tissues,suggesting that NDRG2 can be used as a diagnostic marker for differentiating benign and malignant thyroid lesions.The expression of NDRG2 in PTC was correlated with clinical stage and lymph node metastasis,but not with tumor size,age and sex.It is suggested that the low expression of NDRG2 protein in PTC may be related to the invasion and metastasis of PTC,and the down-regulation of NDRG2expression may be related to the later clinical stage.Detecting the expression of NDRG2 in different tumors may become a powerful tool for early diagnosis,staging and prognosis of tumors in the future.5.The expression of BRAF in PTC tissues was positively correlated with the expression of TSHR,that is,with the decrease of BRAF expression,the expression of TSHR was also decreased,suggesting that the decrease of TSHR expression in PTC tissues may be related to the abnormal expression of BRAF.The expression of NDRG2 in PTC tissues was negatively correlated with the expression of BRAF,that is,with the increasing expression of NDRG2 in cancer tissues,the expression of BRAF showed a downward trend.These results suggested that these three factors could be involved in the occurrence and development of thyroid cancer,and have important guiding significance for early diagnosis of PTC and selection of specific targeted therapy.