Institute of Pathology and Neuropathology, University Hospital of Essen, University of Duisburg-Essen, Germany.
Histopathology. 2010 Apr;56(5):632-40. doi: 10.1111/j.1365-2559.2010.03526.x.
To compare the expression pattern of five microRNAs (miRNAs) (146b, -181b, -21, -221, -222) of papillary thyroid carcinoma (PTC) and hyalinizing trabecular tumour of the thyroid (HTT).
The expression pattern of five miRNAs known to be up-regulated in PTC was retrospectively analysed in 18 HTTs, adjacent normal thyroid tissue, 10 PTCs, 10 follicular adenomas and 10 non-toxic multinodular goitres (MNG) by reverse transcriptase-polymerase chain reaction using the TaqMan miRNA assay. Furthermore, the two common genetic alterations characteristic for PTC, the V600E mutation of the BRAF gene and RET/PTC 1 and 3 rearrangements, were determined in all HTTs. All miRNAs were significantly up-regulated in PTCs, whereas all miRNAs in HTT, normal thyroid tissue, adenomas, and MNGs were down-regulated. Calculating relative changes in gene expression, a 510-fold change of miRNA 146b between PTC and HTT could be observed followed by fold changes between 6.4 and 29 in the remaining miRNAs (P < 0.001). All HTTs lacked BRAF mutations and RET/PTC rearrangements.
Our findings do not support the concept that a high proportion of HTT represents a variant of PTC. It is suggested that HTTs lacking both a miRNA expression pattern characteristic for PTC and RET/PTC rearrangements are re-designated as 'hyalinizing trabecular adenomas'.
比较 5 种微小 RNA（miRNA）（146b、-181b、-21、-221、-222）在甲状腺乳头状癌（PTC）和甲状腺透明细胞小梁肿瘤（HTT）中的表达模式。
采用 TaqMan miRNA 检测法，通过逆转录-聚合酶链反应，对 18 例 HTT、邻近正常甲状腺组织、10 例 PTC、10 例滤泡性腺瘤和 10 例非毒性多结节性甲状腺肿（MNG）中已知在 PTC 中上调的 5 种 miRNA 的表达模式进行了回顾性分析。此外，在所有 HTT 中均确定了两种常见的 PTC 特征性遗传改变，即 BRAF 基因的 V600E 突变和 RET/PTC1 和 3 重排。所有 miRNA 在 PTC 中均显著上调，而 HTT、正常甲状腺组织、腺瘤和 MNG 中的所有 miRNA 均下调。计算基因表达的相对变化，miRNA 146b 在 PTC 和 HTT 之间的变化倍数为 510 倍，其余 miRNA 的变化倍数在 6.4 到 29 之间（P<0.001）。所有 HTT 均缺乏 BRAF 突变和 RET/PTC 重排。
我们的研究结果不支持 HTT 中存在较高比例的 PTC 变异体的概念。建议将既缺乏 PTC 特征性 miRNA 表达模式又缺乏 RET/PTC 重排的 HTT 重新命名为“透明细胞小梁腺瘤”。
