| Objective:Thyroid cancer is a common endocrine tumor, and its incidence on the rise.Diagnosis of thyroid carcinoma mainly relies on clinical symptoms, signs and Doppler ultrasound, CT, and ECT.Surgical management is the main method to treat thyroid carcinoma, and radiotherapy and chemotherapy are used if necessary.Most of them can get good therapeutic effect. The type of pathological,clinical stage,lymph node metastasis and other factors of thyroid cancer, are closely related to their prognosis. In this study, we analyzed the expression level of miR-221,222 in PTCs,paired adjacent normal thyroid tissue,multinodular goitre and normal thyroid tissue to assess if this was associated with selected clinicopathogenetic features in order to guide the diagnosis,differential diagnosis,treatment and prognosis of papillary thyroid carcinoma.Methods:The specimens of thyroid which were obtained from the Department of Thyroid Surgery and Pathology of the First Hospital of Jilin University. Fresh samples from the tumor tissue of PTC and paired adjacent normal thyroid tissue,multinodular goitre were obtained from patients with sporadic PTC and multinodular goiter undergoing surgical resection in the department of thyroid surgery of this hospital from April 2010 to August 2010. Normal thyroid tissue was collected from consenting individuals who had surgery because of laryngeal malignancy but no thyroid disease.The samples were snap-frozen in liquid nitrogen and stored at-70℃. We analyzed the expression levels of miR-221, miR-222 using quantitative real-time polymerase chain reaction in 83 cases tumor tissue of PTCs(T-PTC) and paired adjacent normal thyroid tissue (N-PTC),25 cases of multinodular goiter(MNG) and 15 cases of normal thyroid tissue(NN). We analyzed the expression levels of miR-221,222 in PTCs to assess if thse were associated with selected clinicopathogenetic features.The results were statistically analyzed using SPSS 13.0 software.Results:(1)The expression levels of miR-221 and miR-222 were significant overexpression in T-PTC compared with N-PTC,MNG and N-Thy (P=0.000,0.000,0.000 for miR-221 P=0.000,0.010 and 0.001 for miR-222 respectively). There wae not significant difference between the groups of N-PTC,MNG and N-Thy. ROC curves were constructed (using the data of Normalized expression:2-ΔCT) to evaluate the capability of miR-221 and miR-222 to discriminate between normal and tumor tissue yielded the following AUCs:miR-221,0.803 (95%CI,0.735-0.871);miR-222,0.802 (95%CI,0.737-0.868). Using the optimal cutoff value 0.087(miR-221) and 0.251 (miR-222) respectively, we obtained the following sensitivity and specificity values:miR-221,80.7%and 74.8%, respectively; miR-222,78.3% and 73.2%, respectively.MiR-221,222 quantification for differential diagnosis of thyroid neoplasms were feasible and may improve the accuracy of diagnosis.(2)Both the expression levels of miR-221 and miR-222 in PTCs were not associated with other clinicopathogenetic features except for extrathyroidal invasion.MiR-221 and miR-222 were overexpressed in the grups with extrathyroidal invasion than in those without extrathyroidal invasion(P=0.027,0.047 respectively).So they could be the indexes for extrathyroidal invasion. (3)Expression analysis revealed a significant correlation between miR-221 and miR-222 (r=0.468 P=0.000).This supports that miR-221 and miR-222 are co-transcribed and encoded in one clustersConclusion:(1) Both miR-221 and miR-222 may serve as biomarker for the diagnosis of papillary thyroid carcinoma.(2) Both the expression levels of miR-221 and miR-222 in PTCs were associated with extrathyroidal invasion.So they could serve as indexes for extrathyroidal invasion.(3) Both miR-221 and miR-222 are co-transcribed and encoded in one clusters. |
PDF Full Text Request