Early diagnostic value of miR-191 and miR-494 from fine needle aspiration specimens and peripheral circulation for thyroid carcinoma / 中华内分泌代谢杂志

ABSTRACT

Objective To investigate the different expression levels of death-associated protein kinase ( DAPK) related miR-191 and phosphatase and tensin homolog deleted on chromosome ten ( PTEN) related miR-494 from fine-needle aspiration biopsy ( FNAB) samples and blood of both benign and malignant thyroid nodules, and to find new clinical molecular diagnostic markers. Methods FNAB specimens and peripheral venous blood were collected from 113 patients with thyroid nodules (48 cases of malignant and suspected malignant thyroid nodules, 38 cases of nodular goiter, and 27 cases of thyroid adenomas). The expression levels of miR-191 and miR-494 were detected by realtime fluorescence quantitative reverse transcription PCR ( qRT-PCR ) . qRT-PCR were applied to detect miR-191 and miR-494 expression level in 98 patients with thyroid nodules and peripheral circulation. Receiver operating characteristic curves ( ROC curves) were used to evaluate the sensitivity and specificity of miR-191 and miR-494 to diagnose malignant thyroid nodules. Results (1) The sensitivity of FNAB in diagnosing thyroid cancer was 91. 7％ (44/48) and the specificity was 90. 9％ (30/33),the diagnostic accuracy was 91. 35％. (2) In FNAB samples, as well as in peripheral circulation, the relative expression of miR-191 in thyroid cancer group is significantly lower than that of the benign group, while the relative expression of miR-494 in thyroid cancer group is significantly higher than that of the benign group (P<0. 05). (3) The sensitivity and specificity of miR-191 and miR-494 were acceptable (area under the ROC curve>0. 7). Sensitivity and specificity of miR-191 in FNAB and peripheral circulation were 76. 9％, 73. 5％ and 61. 5％, 64. 1％; miR-494 were 63. 6％,76. 5％ and 72. 7％, 84. 6％respectively. (4) In thyroid cancer FNAB samples and peripheral circulation, the differences between the relative expression level of miR-191 and miR-494, and the clinical characteristics of age, gender, nodule size, and calcification, with or without cervical lymph node enlargement, thyroid function and thyroid antibodies with or without abnormalities were not statistically significant(P>0. 05). Conclusion MiR-191 and miR-494 can be used as molecular diagnostic markers for early diagnosis of thyroid carcinoma with adjunctive FNAB.