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Bad Essen, Germany

Sheu S.-Y.,University of Duisburg - Essen | Vogel E.,University of Duisburg - Essen | Worm K.,University of Duisburg - Essen | Grabellus F.,University of Duisburg - Essen | And 3 more authors.
Histopathology | Year: 2010

Aims: 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). Methods and results: 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. Conclusions: 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'. © 2010 Blackwell Publishing Limited.

Sheu S.-Y.,University of Duisburg - Essen | Grabellus F.,University of Duisburg - Essen | Schwertheim S.,University of Duisburg - Essen | Worm K.,University of Duisburg - Essen | And 3 more authors.
British Journal of Cancer | Year: 2010

Background: Recent studies showed a significant upregulation of distinct microRNAs (miRNAs) in papillary thyroid carcinoma (PTC). The objective of this study was to explore whether this upregulation could also be assigned to distinct histomorphological variants of PTC, especially the follicular variant and other encapsulated follicular thyroid tumours. Methods: We used total RNA of 113 formalin-fixed paraffin-embedded tissues of 50 PTCs ((10 conventional type (PTC-CT), 10 tall cell variants (PTC-TCVs), 30 follicular variants (PTC-FVs)), 10 follicular adenomas (FAs), 10 multinodular goitres (MNGs), 21 follicular thyroid carcinomas and 22 well-differentiated tumours of unknown malignant potential (WDT-UMP) to analyse the miRNA expression pattern of five selected miRNAs (146b, 181b, 21, 221 and 222) using RT-PCR TaqMan miRNA assay to explore the diagnostic utility of this method. Results: The mean values of the expression pattern of all miRNAS in PTCs show a statistically significant difference from those in MNG and FA with fold changes up to 90 for miRNA 146b, P0.001. No differences in expression pattern could be showed between MNG and FA. The PTC-FVs differ significantly from FA in all five miRNAS, from MNG in three and from WDT-UMP in one miRNA with fold changes between 1.7 and 21.2, but failed to be of diagnostic value regarding individual cases with substantial overlaps. Conclusion: We conclude that analysis of a set of five selected miRNAS distinguish common variants of PTC from FA/MNG but failed to be a useful diagnostic method in individual and doubtful cases, especially in the differential diagnosis of encapsulated follicular thyroid tumours. © 2010 Cancer Research UK. All rights reserved.

Otterbach F.,University of Duisburg - Essen | Otterbach F.,West German Cancer Center Essen | Callies R.,University of Duisburg - Essen | Adamzik M.,University of Duisburg - Essen | And 7 more authors.
Breast Cancer Research and Treatment | Year: 2010

Aquaporin1 (AQP1) is a water channel protein that facilitates water flux across cell membranes. It is widely expressed in epithelial and endothelial cells in several tissues. AQP1 is also associated with angiogenesis, cell migration and metastasis in some human malignancies. In this study the immunohistochemical expression of AQP1 in 203 invasive breast carcinomas with long-term follow up was investigated. AQP1 expression was demonstrated in 11 tumours (5.4%) and showed highly significant correlation with high tumour grade, medullary-like histology, "triple-negativity", cytokeratin 14 and smooth muscle actin expression. In univariate analysis, AQP1 was significantly associated with poor prognosis. In multivariate analysis, AQP1 expression proved to be an independent prognostic marker if stratified by age, tumour size, lymph node status, histological grade, ER status and CMF therapy. Our results strongly suggest that AQP1 expression is a new characteristic feature of a particularly aggressive subgroup of basal-like breast carcinomas. © 2009 Springer Science+Business Media, LLC.

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