Diagnostic value of pyruvate kinase M2 gene for papillary thyroid carcinoma in fine-needle aspiration specimens

Abstract

Objective To investigate the diagnostic value of pyruvate kinase M2(PKM2)gene expression in papillary thyroid carcinoma(PTC). Methods Quantitative real-time PCR(RT-qPCR)was used to detect the expression of PKM2 mRNA in benign thyroid nodules, PTC, and normal thyroid tissues around nodules of fine-needle aspiration(FNA)specimens. Immunohistochemistry(IHC)was used to detect the expression of PKM2 protein in thyroid tissue after thyroidectomy. The receiver operating characteristic curve was constructed to evaluate the diagnostic value of PKM2 in PTC. Results The expression of PKM2 mRNA was detectable in FNA specimens of thyroid nodules, higher in PTC than those in normal thyroid tissue and benign thyroid nodules(P 0.05). The expression level of PKM2 mRNA in FNA specimens of thyroid nodules was paralleled with the expression level of PKM2 protein in postoperation pathological tissues. The accuracy, sensitivity, specificity of PKM2 gene in the diagnosis of PTC were 62.8%, 46.9%, and 95.7%, respectively. The accuracy and sensitivity of PKM2 combined with BRAFV600E were increased to 87.6% and 83.7%, significantly higher than those of single detection (P<0.05) . Conclusion Detection of PKM2 gene in FNA specimens is highly specific in the diagnosis of PTC, making it a valuable molecular marker for preoperative diagnosis. The combination of PKM2 and BRAFV600E detection shows a higher diagnosis efficiency. Key words: Papillary thyroid carcinoma; Pyruvate kinase M2; Fine-needle aspiration