[show abstract][hide abstract] ABSTRACT: Skull base metastasis from differentiated thyroid carcinoma including follicular thyroid carcinoma (FTC) and papillary thyroid carcinoma (PTC) is a rare clinical entity. Eighteen FTC cases and 10 PTC cases showing skull base metastasis have been reported. The most common symptom of skull base metastasis from FTC and PTC is cranial nerve dysfunction. Bone destruction and local invasion to the surrounding soft tissues are common on radiological imaging. Skull base metastases can be the initial clinical presentation of FTC and PTC in the presence of silent primary sites. The possibility of skull base metastasis from FTC and PTC should be considered in patients with the clinical symptoms of cranial nerve dysfunction and radiological findings of bone destruction. A variety of genetic alterations in thyroid tumors have been identified to have a fundamental role in their tumorigenesis. Molecular histochemical studies are useful for elucidating the histopathological features of thyroid carcinoma. Recent molecular findings may provide novel molecular-based treatment strategies for thyroid carcinoma.
Acta histochemica et cytochemica official journal of the Japan Society of Histochemistry and Cytochemistry 10/2013; 46(5):129-136. · 1.48 Impact Factor
[show abstract][hide abstract] ABSTRACT: We modified and tested S/MAR (scaffold/matrix attachment region) episomal vectors. The new vectors would be useful in obtaining cells stably expressing fluorescent-protein tagged transgenes with small, mostly within 10-fold cell-to-cell fluctuations. In the vectors, the same transcript directs episomal replication and expression of transgene/antibiotic marker, and only antibiotic selection without any other extra steps was sufficient to obtain desired stable cells, including those expressing two different proteins simultaneously. Furthermore, the two test cases (i.e., expression of human growth hormone in AtT20 and four PKC isoforms in HEK293) would prove useful in visualizing and analyzing regulatory processes involving these proteins.
[show abstract][hide abstract] ABSTRACT: There have been several reports of temozolomide (TMZ) treatment of pituitary carcinomas and atypical adenomas. O(6)-methyl-guanine-DNA methyltransferase is not the sole molecule determining the sensitivity to TMZ in pituitary carcinomas and atypical adenomas. The Japan Society of Hypothalamic and Pituitary Tumors study suggests that MSH6, one of mismatch repair pathway enzyme, fulfills a contributory role to the efficacy of TMZ treatment for pituitary carcinomas and atypical adenomas. The preserved MSH6 function might be essential for the responsiveness to TMZ treatment in pituitary carcinomas and atypical adenomas.
Medical Molecular Morphology 08/2013; · 1.17 Impact Factor
[show abstract][hide abstract] ABSTRACT: Adult growth hormone (GH) deficiency (AGHD) in Japan is diagnosed based on peak GH concentrations during GH provocative tests such as GHRP-2 stimulation test. In this study, we aimed to evaluate the ability of serum insulin-like growth factor-1 (sIGF-1) and urinary GH (uGH) at the time of awakening to diagnose AGHD. Fifty-nine patients with pituitary disease (32 men and 27 women; age 20-85 y (57.5 ± 15.5, mean ± SD) underwent GHRP-2 stimulation and sIGF-1 testing. Thirty-six and 23 patients were diagnosed with and without severe AGHD, respectively based on a peak GH response of <9 ng/mL to GHRP-2 stimulation. Serum IGF-1 was evaluated as a standard deviation score (IGF-1 SDS) based on age and sex. We determined whether uGH levels in urine samples from 42 of the 59 patients at awakening were above or below the sensitivity limit. We evaluated IGF-1 SDS and uGH levels in a control group of 15 healthy volunteers. Values for IGF-1 SDS were significantly lower in patients with, than without (-2.07 ± 1.77 vs.-0.03 ± 0.92, mean ± SD; p < 0.001) AGHD whereas the range of IGF-1 SDS substantially overlapped at >-1.4. IGF-1 SDS discriminated AGHD more effectively in patients aged ≤60 years. The χ(2) test revealed a statistical relationship between uGH and AGHD (test statistic: 7.0104 ≥ χ(2) (1; 0.01) ＝ 6.6349). When IGF-1 SDS is <-1.4 or uGH is below the sensitivity limit, AGHD can be detected with high sensitivity.
[show abstract][hide abstract] ABSTRACT: In the original manuscript, the word "fluorescein" was erroneously used indistinctly for "fluorescence" and "fluorescent". Furthermore, "cyan fluorescent protein" was misspelled. These errors have been amended in an amended version of the manuscript, which is available from the Molecules website. The authors and publisher apologize for the inconvenience.
[show abstract][hide abstract] ABSTRACT: Combined in situ hybridization (ISH) and immunohistochemistry (IHC) under electron microscopy (EM-ISH & IHC) has sufficient ultrastructural resolution to provide two-dimensional images of subcellular localization of pituitary hormone and its mRNA in a pituitary cell. The advantages of semiconductor nanocrystals (Quantum dots; Qdots) and confocal laser scanning microscopy (CLSM) enable us to obtain three-dimensional images of the subcellular localization of pituitary hormone and its mRNA. Both EM-ISH & IHC and ISH & IHC using Qdots and CLSM are useful for understanding the relationship between protein and mRNA simultaneously in two or three dimensions. CLSM observation of rab3B and SNARE proteins such as SNAP-25 and syntaxin revealed that both rab3B and SNARE system proteins play an important role and work together as the exocytotic machinery in anterior pituitary cells. Another important issue is the intracellular transport and secretion of pituitary hormone. An experimental pituitary cell line, the GH3 cell, in which growth hormone (GH) is linked to enhanced yellow fluorescein protein (EYFP), has been developed. This stable GH3 cell secretes GH linked to EYFP upon being stimulated by Ca(2+) influx or Ca(2+) release from storage. This GH3 cell is useful for real-time visualization of the intracellular transport and secretion of GH. These three methods enable us to visualize consecutively the processes of transcription, translation, transport, and secretion of pituitary hormone.
Medical Molecular Morphology 06/2011; 44(2):63-70. · 1.17 Impact Factor
[show abstract][hide abstract] ABSTRACT: The case presented here describes the clinical evolution of a pituitary carcinoma from an atypical prolactinoma after temozolomide (TMZ) treatment. The mechanism of acquisition of TMZ resistance was analyzed.
A 60-year-old woman with atypical prolactinoma had been treated for 7 years with multiple therapies, including dopamine agonists, surgical intervention (5 times), conventional radiotherapy, and radiosurgery. The patient deteriorated as a result of tumor enlargement. Ten cycles of TMZ therapy, 200 mg/m for 5 days every 4 weeks, improved the patient's performance status and caused tumor shrinkage. Six months after discontinuation of TMZ, the tumor progressed into pituitary carcinoma with tumor regrowth and intraventricular dissemination. TMZ therapy was ineffective this time. A sixth surgery and salvage chemotherapy failed to improve the patient's condition, and she died 9 years after the first diagnosis. Throughout the treatment course, O6-methyl-guanine-DNA methyltransferase (MGMT) was immunonegative in the tumor specimens, including the TMZ-refractory pituitary carcinoma. Mutation of p53 was identified in both the atypical prolactinoma and pituitary carcinoma. In contrast, major differences were noted for mismatch repair protein MSH6 immunostaining: Although MSH6 was diffusely immunopositive in the atypical adenoma, it became immunonegative when the tumor evolved into TMZ-refractory pituitary carcinoma.
Loss of MSH6 occurred during the progression from an atypical prolactinoma to a pituitary carcinoma, which may have caused resistance to TMZ treatment. This case suggests that preserving MSH6 function is essential for responsiveness to TMZ treatment in MGMT-negative and p53-mutated atypical pituitary adenoma or pituitary carcinoma.
[show abstract][hide abstract] ABSTRACT: In situ hybridization (ISH) at the electron microscopic (EM) level is essential for elucidating the intracellular distribution and role of mRNA in protein synthesis. EM-ISH is considered to be an important tool for clarifying the intracellular localization of mRNA and the exact site of pituitary hormone synthesis on the rough endoplasmic reticulum. A combined ISH and immunohistochemistry (IHC) under EM (EM-ISH&IHC) approach has sufficient ultrastructural resolution, and provides two-dimensional images of the subcellular localization of pituitary hormone and its mRNA in a pituitary cell. The advantages of semiconductor nanocrystals (quantum dots, Qdots) and confocal laser scanning microscopy (CLSM) enable us to obtain three-dimensional images of the subcellular localization of pituitary hormone and its mRNA. Both EM-ISH&IHC and ISH & IHC using Qdots and CLSM are useful for understanding the relationships between protein and mRNA simultaneously in two or three dimensions. CLSM observation of rab3B and SNARE proteins such as SNAP-25 and syntaxin has revealed that both rab3B and SNARE system proteins play important roles and work together as the exocytotic machinery in anterior pituitary cells. Another important issue is the intracellular transport and secretion of pituitary hormone. We have developed an experimental pituitary cell line, GH3 cell, which has growth hormone (GH) linked to enhanced yellow fluorescein protein (EYFP). This stable GH3 cell secretes GH linked to EYFP upon stimulation by Ca²+ influx or Ca²+ release from storage. This GH3 cell line is useful for the real-time visualization of the intracellular transport and secretion of GH. These three methods from conventional immunohistochemistry and fluorescein imaging allow us to consecutively visualize the process of transcription, translation, transport and secretion of anterior pituitary hormone.
[show abstract][hide abstract] ABSTRACT: Mouse transgenesis has proven invaluable for analysis of gene function and generation of human disease models. We describe here the development of a pronuclear injection-based targeted transgenesis (PITT) system, involving site-specific integration in fertilized eggs. The system was applied to two different genomic target loci to generate a series of transgenic lines including fluorescent mice, which reproducibly displayed strong, ubiquitous and stable transgene expression. We also demonstrated that knockdown mice could be readily generated by PITT by taking advantage of the reproducible and highly efficient expression system. The PITT system, which circumvents the problem of unpredictable and unstable transgene expression of conventional random-integration transgenic mice, reduces the time, cost and effort needed to generate transgenic mice, and is potentially applicable to both in vivo 'gain-of-function' and 'loss-of-function' studies.
Nucleic Acids Research 09/2010; 38(22):e198. · 8.28 Impact Factor
[show abstract][hide abstract] ABSTRACT: Sick building syndrome (SBS) is a chronic disorder caused by exposure to diverse indoor environmental or chemical pollutants. This study examined the association between seven detoxification genes (CYP1A1, CYP2E1, EPHX1, GSTM1, GSTT1, GSTP1, and NAT2) and SBS in the Japanese population. One hundred eighty patients with SBS and 401 healthy controls were enrolled in this study. We examined the prevalence for total of eleven genetic polymorphisms of detoxification genes. However, no statistically significant differences in allele and genotype frequency distributions of eleven genetic polymorphisms of these detoxification genes were found between patients and controls. On this basis, we conclude that the polymorphisms that we assessed for the detoxification genes do not contribute to the etiology of SBS.
Environmental toxicology and pharmacology. 03/2010; 29(2):190-4.
[show abstract][hide abstract] ABSTRACT: SIRT1, a NAD-dependent deacetylase, has diverse roles in a variety of organs such as regulation of endocrine function and metabolism. However, it remains to be addressed how it regulates hormone release there.
Here, we report that SIRT1 is abundantly expressed in pituitary thyrotropes and regulates thyroid hormone secretion. Manipulation of SIRT1 level revealed that SIRT1 positively regulated the exocytosis of TSH-containing granules. Using LC/MS-based interactomics, phosphatidylinositol-4-phosphate 5-kinase (PIP5K)gamma was identified as a SIRT1 binding partner and deacetylation substrate. SIRT1 deacetylated two specific lysine residues (K265/K268) in PIP5Kgamma and enhanced PIP5Kgamma enzyme activity. SIRT1-mediated TSH secretion was abolished by PIP5Kgamma knockdown. SIRT1 knockdown decreased the levels of deacetylated PIP5Kgamma, PI(4,5)P(2), and reduced the secretion of TSH from pituitary cells. These results were also observed in SIRT1-knockout mice.
Our findings indicated that the control of TSH release by the SIRT1-PIP5Kgamma pathway is important for regulating the metabolism of the whole body.
PLoS ONE 01/2010; 5(7):e11755. · 3.73 Impact Factor
[show abstract][hide abstract] ABSTRACT: To investigate the influence of preoperatively elevated growth hormone to bone mass in acromegalic patients, bone mineral density (BMD), and urinary type I collagen N-telopeptide were analyzed in postoperative patients with somatotroph adenomas (SA), in comparison with patients with clinically nonfunctioning adenomas (NF). The mean T and z scores of BMD in the radius of postoperative patients with SA were significantly higher than those of postoperative patients with NF. There was no significant difference in the mean T and z scores of BMD in the lumbar spine between postoperative patients with SA and those with NF. Thus, BMD in the radius is preferentially maintained in postoperative patients with SA. This result suggests that the preoperative elevation of growth hormone and insulin-like growth factor-1 are beneficial in the maintenance of bone mass in acromegalic patients.
The Endocrinologist 08/2009; 19(5):208-210. · 0.12 Impact Factor
[show abstract][hide abstract] ABSTRACT: Combined medical treatment with long acting octreotide and cabergoline is now used with active patients with acromegaly and can reduce serum growth hormone (GH) and insulin-like growth factor-1 levels. In this article, we analyzed again the molecular aspects of the previously reported rare GH-releasing hormone (GHRH)-producing somatotroph adenoma, and introduce the effects of the combined medical treatment using octreotide LAR and cabergoline for GHRH-producing somatotroph adenoma. The present GHRH-producing somatotroph adenoma had a high Ki-67 staining index, weak, and cytoplasmic-dominant immunostaining of somatostatin receptor 2A, and no gsp mutation. This adenoma was predicted to be resistant to the medical therapy using octreotide LAR. In this extremely rare GHRH-producing pituitary somatotroph adenoma, octreotide LAR alone cannot reduce random GH and insulin-like growth factor-1 levels sufficiently, but combined medical therapy with octreotide LAR and cabergoline can reduce them into the normal range. We show that combined medical treatment with octreotide LAR and cabergoline was effective for a somatotroph adenoma that had a high proliferative potential, weak and cytoplasmic-dominant immunostaining of somatostatin receptor 2A, and no gsp mutation, and has active GH production and secretion regulated by locally generated GHRH from adenoma cell.
The Endocrinologist 10/2008; 18(6):266-269. · 0.12 Impact Factor
[show abstract][hide abstract] ABSTRACT: It is unclear how hepatic adiponectin resistance and sensitivity mediated by the adiponectin receptor, AdipoR2, contributes to the progression of nonalcoholic steatohepatitis (NASH). The aim of this study was to examine the roles of hepatic AdipoR2 in NASH, using an animal model. We fed C57BL/6 mice a methionine-deficient and choline-deficient (MCD) diet for up to 8 weeks and analyzed changes in liver pathology caused by either an AdipoR2 short hairpin RNA-expressing adenovirus or an AdipoR2-overexpressing adenovirus. Inhibition of hepatic AdipoR2 expression aggravated the pathological state of NASH at all stages: fatty changes, inflammation, and fibrosis. In contrast, enhancement of AdipoR2 expression in the liver improved NASH at every stage, from the early stage to the progression of fibrosis. Inhibition of AdipoR2 signaling in the liver diminished hepatic peroxisome proliferator activated receptor (PPAR)-alpha signaling, with decreased expression of acyl-CoA oxidase (ACO) and catalase, leading to an increase in lipid peroxidation. Hepatic AdipoR2 overexpression had the opposite effect. Reactive oxygen species (ROS) accumulation in liver increases hepatic production of transforming growth factor (TGF)-beta1 at all stages of NASH; adiponectin/AdipoR2 signaling ameliorated TGF-beta-induced ROS accumulation in primary cultured hepatocytes, by enhancing PPAR-alpha activity and catalase expression. CONCLUSION: The adiponectin resistance and sensitivity mediated by AdipoR2 in hepatocytes regulated steatohepatitis progression by changing PPAR-alpha activity and ROS accumulation, a process in which TGF-beta signaling is implicated. Thus, the liver AdipoR2 signaling pathway could be a promising target in treating NASH.
[show abstract][hide abstract] ABSTRACT: Recently, in order to elucidate the role of rab3B in porosome, we have observed the incorporation of rab3B in the secretion of GH through porosome under confocal laser scanning microscopy (CLSM). Transfected cells with GH-EYFP fusion protein and rab3B-ECFP fusion protein were observed under CLSM, which showed the colocalization of EYFP-GH and ECFP-rab3B in the budding configuration of secretory process. These structural and functional images of rab3B imply the incorporation of rab3B in the secretion of GH through porosome.
Folia Histochemica et Cytobiologica 02/2008; 46(4):419-21. · 1.10 Impact Factor
[show abstract][hide abstract] ABSTRACT: R-Ras is a Ras-family small GTPase that regulates various cellular functions such as apoptosis and cell adhesion. Here, we demonstrate a role of R-Ras in exocytosis. By the use of specific anti-R-Ras antibody, we found that R-Ras was enriched on both early and recycling endosomes in a wide range of cell lines. Using a fluorescence resonance energy transfer-based probe for R-Ras activity, R-Ras activity was found to be higher on endosomes than on the plasma membrane. This high R-Ras activity on the endosomes correlated with the accumulation of an R-Ras effector, the Rgl2/Rlf guanine nucleotide exchange factor for RalA, and also with high RalA activity. The essential role played by R-Ras in inducing high levels of RalA activity on the endosomes was evidenced by the short hairpin RNA (shRNA)-mediated suppression of R-Ras and by the expression of R-Ras GAP. In agreement with the reported role of RalA in exocytosis, the shRNA of either R-Ras or RalA was found to suppress calcium-triggered exocytosis in PC12 pheochromocytoma cells. These data revealed that R-Ras activates RalA on endosomes and that it thereby positively regulates exocytosis.
Molecular Biology of the Cell 06/2007; 18(5):1850-60. · 4.60 Impact Factor
[show abstract][hide abstract] ABSTRACT: While tumour necrosis factor alpha (TNF-alpha) appears to be associated with the development of non-alcoholic steatohepatitis (NASH), its precise role in the pathogenesis of NASH is not well understood.
Male mice deficient in both TNF receptors 1 (TNFR1) and 2 (TNFR2) (TNFRDKO mice) and wild-type mice were fed a methionine and choline deficient (MCD) diet or a control diet for eight weeks, maintaining isoenergetic intake.
MCD dietary feeding of TNFRDKO mice for eight weeks resulted in attenuated liver steatosis and fibrosis compared with control wild-type mice. In the liver, the number of activated hepatic Kupffer cells recruited was significantly decreased in TNFRDKO mice after MCD dietary feeding. In addition, hepatic induction of TNF-alpha, vascular cell adhesion molecule 1, and intracellular adhesion molecule 1 was significantly suppressed in TNFRDKO mice. While in control animals MCD dietary feeding dramatically increased mRNA expression of tissue inhibitor of metalloproteinase 1 (TIMP-1) in both whole liver and hepatic stellate cells, concomitant with enhanced activation of hepatic stellate cells, both factors were significantly lower in TNFRDKO mice. In primary cultures, TNF-alpha administration enhanced TIMP-1 mRNA expression in activated hepatic stellate cells and suppressed apoptotic induction in activated hepatic stellate cells. Inhibition of TNF induced TIMP-1 upregulation by TIMP-1 specific siRNA reversed the apoptotic suppression seen in hepatic stellate cells.
Enhancement of the TNF-alpha/TNFR mediated signalling pathway via activation of Kupffer cells in an autocrine or paracrine manner may be critically involved in the pathogenesis of liver fibrosis in this NASH animal model.
[show abstract][hide abstract] ABSTRACT: Combined in situ hybridization (ISH) and immunohistochemistry (IHC) under electron microscopy (EM-ISH&IHC) has sufficient ultrastructural resolution and provides two-dimensional images of subcellular localization of pituitary hormone and its mRNA in a pituitary cell. The advantages of semiconductor nanocrystals (Quantum dots, Qdots) and confocal laser scanning microscopy (CLSM) enable us to obtain three-dimensional images of subcellular localization of pituitary hormone and its mRNA. Both EM-ISH&IHC and ISH&IHC using Qdots and CLSM are useful for understanding the relation between protein and mRNA simultaneously in two or three dimensions. Another important issue is the intracellular transport and secretion of pituitary hormone. We have developed an experimental pituitary cell line, the GH3 cell, which has growth hormone (GH) linked to enhanced yellow fluorescein protein (EYFP). This stable GH3 cell secretes GH linked to EYFP upon stimulated by Ca2+ influx or Ca2+ release from storage. This GH3 cell is useful for real-time visualization of the intracellular transport and secretion of GH. These three methods enable us to visualize consecutively the process of transcription, translation, transport, and secretion of pituitary hormone.