Maiko Takeda

9p21 deletion in the diagnosis of malignant mesothelioma, using fluorescence in situ hybridization analysis.

Homozygous deletion of 9p21, the locus harboring the p16 gene, has been reported as one of the most common genetic alterations in malignant mesotheliomas (MMs). Previous studies showed that this alteration might be useful for differentiating benign from malignant mesothelial tumors in cytology and surgical specimens. Although the diagnostic utility of 9p21 homozygous deletion by fluorescence in situ hybridization (FISH) analysis has been reported only recently, it has not been well demonstrated. The purpose of this study is to evaluate the diagnostic utility of 9p21 homozygous deletion assessed by FISH in mesothelial neoplasm and hyperplasia of Japanese patients using paraffin‐embedded tissue. Simultaneously, p16 protein immunoexpression was explored as a potential diagnostic aid. FISH analysis demonstrated 9p21 deletion in 35 of 40 cases with MM (88%) (P < 0.001). In contrast, no cases of adenomatoid tumor, benign mesothelial multicystic tumor, reactive mesothelial hyperplasia or pleuritis showed 9p21 deletion (P < 0.005). 9p21 homozygous deletion correlated well with p16 protein expression in the tumor cells. Our study suggests that 9p21 homozygous deletion assessed by FISH on paraffin‐embedded tissue may be very useful for differentiating MM from reactive mesothelial proliferation.

Invasive growth of hepatic angiomyolipoma; a hitherto unreported ominous histological feature

Aims : Although histological features of hepatic angiomyolipoma (AML) are highly variable, true malignant change is extremely rare. The aim was to review the histological features of invasive growth and clinical outcomes in 39 cases of hepatic AML.

Genomic gains and losses in malignant mesothelioma demonstrated by FISH analysis of paraffin-embedded tissues

Aims Malignant mesothelioma (MM) results from the accumulation of a number of acquired genetic events at the onset. In MM, the most frequent changes were losses in 9p21, 1p36, 14q32 and 22q12, and gains in 5p, 7p and 8q24 by comparative genomic hybridisation analysis. Although the diagnostic utility of 9p21 homozygous deletion by fluorescence in situ hybridisation (FISH) analysis in MM has been reported recently, alterations of other genes have not been examined to any great extent. This study analysed the frequency of various genomic gains and losses in MM using FISH analysis. Materials and methods The authors performed a FISH analysis using paraffin-embedded tissues from 42 cases of MM. Results Chromosomal losses in MM were found at 9p21 (83%), 1p36 (43%), 14q32 (43%) and 22q12 (38%), whereas gains were found at 5p15 (48%), 7p12 (38%) and 8q24 (45%). There were no cases of adenomatoid tumour, benign mesothelial multicystic tumour, reactive mesothelial hyperplasia or pleuritis showing any gains or losses. At least one genomic abnormality was identified in all cases of MM. Among various histological subtypes, the chromosomal abnormality tended to be more common in cases showing sarcomatous elements (biphasic or pure sarcomatoid) than in cases showing an epithelioid histology. Conclusions The authors found various genomic gains and losses in MM by FISH analysis. The frequency of each genomic gain or loss examined in MM by FISH analysis almost agreed with the comparative genomic hybridisation technique in previous studies. This study suggests that genomic evaluation by FISH analysis might be helpful in distinguishing MM from benign mesothelial proliferation.

Angiomyolipoma of the liver: a reappraisal of morphological features and delineation of new characteristic histological features from the clinicopathological findings of 55 tumours in 47 patients.

Nonomura A, Enomoto Y, Takeda M, Takano M, Morita K & Kasai T 
(2012) Histopathology 61, 863–880

ADAMTS13 safeguards the myocardium in a mouse model of acute myocardial infarction

Masaaki Doi1,2; Hideto Matsui1; Yukiji Takeda3; Yoshihiko Saito3; Maiko Takeda4; Yasunori Matsunari1,5; Kenji Nishio6; Midori Shima2; Fumiaki Banno7; Masashi Akiyama7; Koichi Kokame7; Toshiyuki Miyata7; Mitsuhiko Sugimoto1 1Department of Regulatory Medicine for Thrombosis, Nara Medical University, Kashihara, Japan; 2Department of Pediatrics, Nara Medical University, Kashihara, Japan; 3Department of Internal Medicine, Nara Medical University, Kashihara, Japan; 4Department of Pathology, Nara Medical University, Kashihara, Japan; 5Department of Anesthesiology, Nara Medical University, Kashihara, Japan; 6Department of General Medicine, Nara Medical University, Kashihara, Japan; 7Department of Molecular Pathogenesis, National Cerebral and Cardiovascular Center, Osaka, Japan

Synergistic activations of REG I α and REG I β promoters by IL-6 and Glucocorticoids through JAK/STAT pathway in human pancreatic β cells.

Reg (Regenerating gene) gene was originally isolated from rat regenerating islets and its encoding protein was revealed as an autocrine/paracrine growth factor for β cells. Rat Reg gene is activated in inflammatory conditions for β cell regeneration. In human, although five functional REG family genes (REG Iα, REG Iβ, REG III, HIP/PAP, and REG IV) were isolated, their expressions in β cells under inflammatory conditions remained unclear. In this study, we found that combined addition of IL-6 and dexamethasone (Dx) induced REG Iα and REG Iβ expression in human 1.1B4 β cells. Promoter assay revealed that a signal transducer and activator of transcription- (STAT-) binding site in each promoter of REG Iα (TGCCGGGAA) and REG Iβ (TGCCAGGAA) was essential for the IL-6+Dx-induced promoter activation. A Janus kinase 2 (JAK2) inhibitor significantly inhibited the IL-6+Dx-induced REG Iα and REG Iβ transcription. Electrophoretic mobility shift assay and chromatin immunoprecipitation revealed that IL-6+Dx stimulation increased STAT3 binding to the REG Iα promoter. Furthermore, small interfering RNA-mediated targeting of STAT3 blocked the IL-6+Dx-induced expression of REG Iα and REG Iβ. These results indicate that the expression of REG Iα and REG Iβ should be upregulated in human β cells under inflammatory conditions through the JAK/STAT pathway.

Prevention of Reg I-induced β-cell apoptosis by IL-6/dexamethasone through activation of HGF gene regulation.

Reg (regenerating gene) product, Reg protein, is induced in pancreatic β-cells and acts as autocrine/paracrine growth factor for regeneration via the cell surface Reg receptor. However, high concentrations of Reg I protein induced β-cell apoptosis. In the present study, we found that hepatocyte growth factor (HGF) attenuated the β-cell apoptosis induced by the high concentrations of Reg I protein and that the combined stimulation of interleukin-6 (IL-6) and dexamethasone (Dx) induced the accumulation of HGF mRNA as well as Reg I mRNA in β-cells. The accumulation of the HGF mRNA was caused by the activation of the HGF promoter. Deletion analysis revealed that the region of -96 to -92 of the HGF gene was responsible for the promoter activation by IL-6+Dx. The promoters contain a consensus transcription factor binding sequence for signal transducer and activator of transcription (STAT). Site-directed mutations of STAT-binding motif in the region markedly attenuated the HGF promoter activity. Chromatin immunoprecipitation assay showed that STAT3 is located at the active HGF promoter in response to IL-6+Dx stimulation. These results strongly suggest that the combined stimulation of IL-6 and glucocorticoids induces the activation of both Reg and HGF genes and that the anti-apoptotic effects of HGF against the Reg I-induced apoptosis may help β-cell regeneration by Reg I protein.

Cytopathological features of mammary analogue secretory carcinoma—Review of literature

Mammary analogue secretory carcinoma (MASC) is a recently described salivary gland tumor that morphologically resembles mammary secretory carcinoma and carries the identical ETV6‐NTRK3 fusion gene. We report a surgical resected case of MASC in the parotid gland of a 41‐year‐old man. The cytological smears of a preoperative fine‐needle aspiration showed many sheets and crowded clusters of monotonous epithelioid cells with mild atypia, suggestive of monomorphic tumor. Histologically, the tumor was composed of cuboidal cells with follicular, tubular, and solid structures, reminiscent of acinic cell carcinoma of follicular variant, which had been previously classified. This case had ETV6‐NTRK3 fusion gene transcript confirmed by fluorescence in situ hybridization and reverse transcription polymerase chain reaction. In the cytological and histopathological diagnosis of monomorphic tumor of salivary gland, MASC needs to be taken into consideration as a differential diagnosis. Further immunohistochemical and gene analyses are needed in diagnosis of MASC. Diagn. Cytopathol. 2015;43:131–137.

Involvement of autoimmunity to REG, a regeneration factor, in patients with primary Sjögren's syndrome

The regenerating gene (Reg) was isolated originally as a gene specifically over‐expressed in regenerating pancreatic islets and constitute a growth factor family. Reg gene product (Reg) is important in the pathophysiology of various human inflammatory diseases. Recently, the possible involvement of human REG in the regeneration of salivary ductal epithelial cells of patients with primary Sjögrens syndrome (SS) was reported. However, the expression of the REG family genes in minor salivary glands (MSG) and the occurrence of anti‐REG Iα autoantibodies in SS patients were obscured. In this study, we examined the expression of REG family genes in the MSG of SS and screened anti‐REG Iα autoantibodies in SS. The mRNA levels of REG family genes in MSG were quantified using real‐time reverse transcription–polymerase chain reaction (RT–PCR) and REG Iα expression in the MSG was analysed by immunohistochemistry. The mRNA level of REG Iα in the MSG of SS patients was significantly higher than that of control. REG Iα protein was expressed highly in SS ductal epithelial cells. Anti‐REG Iα autoantibodies in the sera were found in 11% of SS. All the MSG in the anti‐REG Iα autoantibody‐positive group showed REG Iα expression, whereas only 40% showed REG Iα expression in the anti‐REG Iα autoantibody‐negative group. The anti‐REG Iα autoantibody‐positive group showed significantly lower saliva secretion and a higher ratio of grade 4 (by Rubin–Holt) in sialography. These data suggest strongly that autoimmunity to REG Iα might play a role in the degeneration of MSG ductal epithelial cells in primary SS.

Epidermal growth factor receptor mutations in malignant pleural and peritoneal mesothelioma

Background Epidermal growth factor receptor (EGFR) gene mutation at the kinase domain and EGFR gene amplification are reported to be predictors of the response to EGFR tyrosine kinase inhibitors in lung cancer cases. In malignant mesothelioma (MM), the role of EGFR is less clear. Methods Thirty-eight MM specimens were submitted to EGFR mutation evaluation, and compared with the results of immunohistochemical staining and fluorescence in situ hybridization (FISH) analysis. DNA was extracted from paraffin blocks and PCR was performed to amplify exon regions 18–21 of the EGFR gene. Direct sequencing of the purified PCR products was performed. Results Five EGFR missense mutations were detected in six of the 38 patients (16%); two of these mutations were novel, two were originally detected in non-small cell lung carcinoma, and one resembled a location previously noted for malignant peritoneal mesothelioma. Conclusion As far as the authors are aware there has been no report of the EGFR mutation of MM in Japanese cases, but in this study EGFR missense mutations were detected in some cases. EGFR mutation results were not related to immunohistochemical and FISH analysis.