Pathogenesis of selective damage of granule cell layer in cerebellum of rats exposed to methylmercury.

Granule cell-selective toxicity of methylmercury in the cerebellum is one of the main unresolved issues in the pathogenesis of Minamata disease. Rats were orally administered methylmercury chloride (10 mg/kg/day) for 5 consecutive days, and their brains were harvested on days 1, 7, 14, 21, or 28 after the last administration for histological examination of the cerebellum. It was found that methylmercury caused a marked degenerative change to the granule cell layers but not to the Purkinje cell layers. The generative change of the granule cell layer was due to cell death, including apoptosis, which occurred at day 21 and beyond after the methylmercury administration. Meanwhile, cytotoxic T-lymphocytes and macrophages had infiltrated the granule cell layer. Additionally, granule cells are shown to be a cell type susceptible to TNF-α. Taken together, these results suggest that methylmercury causes small-scale damage to granule cells, triggering the infiltration of cytotoxic T-lymphocytes and macrophages into the granule cell layer, which secrete tumor necrosis factor-α (TNF-α) to induce apoptosis in granule cells. This chain is established based on the susceptibility of granule cells to methylmercury, the ability of cytotoxic T lymphocytes and macrophages to synthesize and secrete TNF-α, and the sensitivity of granule cells to TNF-α and methylmercury. We propose to call the pathology of methylmercury-induced cerebellar damage the "inflammation hypothesis."

Protective Effects of Collagen Tripeptides in Human Aortic Endothelial Cells by Restoring ROS-Induced Transcriptional Repression.

Collagen tripeptide (CTP) is defined as a functional food material derived from collagenase digests of type I collagen and contains a high concentration of tripeptides with a Gly-X-Y sequence. CTP has several biological effects, including the acceleration of fracture healing, ameliorating osteoarthritis, and improving dryness and photoaging of the skin. Recently, an antiatherosclerotic effect of CTP has been reported, although its molecular mechanism is yet to be determined. In this study, we examined the effects of CTP on primary cultured human aortic endothelial cells (HAECs) under oxidative stress, because oxidative endothelial dysfunction is a trigger of atherosclerosis. DNA microarray and RT-qPCR analyses showed that CTP treatment recovered the downregulated expression of several genes, including the interleukin-3 receptor subunit alpha (IL3RA), which were suppressed by reactive oxygen species (ROS) treatment in HAECs. Furthermore, IL3RA knockdown significantly decreased the viability of HAECs compared with control cells. RT-qPCR analysis also showed that solute carrier 15 family peptide transporters, which are involved in CTP absorption into cells, were expressed in HAECs at levels more than comparable to those of a CTP-responsive human osteoblastic cell line. These results indicated that CTP exerts a protective effect for HAECs, at least in part, by regulating the recovery of ROS-induced transcriptional repression.

Effect of Collagen Tripeptide on Atherosclerosis in Healthy Humans.

AIM: Collagen tripeptide (CTP) is a functional food with a high content of Gly-X-Y tripeptides derived from collagen. The objective of this study was to evaluate the effect of CTP administration on the development of atherosclerosis in healthy individuals. METHODS: The present study was conducted in the form of an open-label, single-dose trial for 6 months. All subjects ingested CTP twice daily: at breakfast and supper (total intake per day: 16 g). The effect of CTP on atherosclerosis was verified by measuring several indices, including serum lipid levels, toxic advanced glycation end-products (TAGE), and the cardio-ankle vascular index (CAVI), at baseline and 6 months. RESULTS: The low-density lipoprotein cholesterol (LDL-C) to high-density lipoprotein cholesterol (HDL-C) ratio (LDL-C/HDL-C ratio) was significantly reduced in patients with an initial ratio of ≥2.5 (p=0.025). A significant reduction in TAGE was observed in all the subjects (p=0.031) and in the high-risk group (p=0.024). A significant reduction in CAVI was observed in all the subjects (right side: p=0.048, left side: p=0.047). As a result of multiple regression analysis, a significant relationship between the change in CAVI and that in each factor was not observed. No adverse events were observed during the study period. CONCLUSIONS: The results of the present study indicate that CTP contributes to the prevention and treatment of atherosclerosis in healthy humans (UMIN000018525).

Effects of oral administration of tripeptides derived from type I collagen (collagen tripeptide) on atherosclerosis development in hypercholesterolemic rabbits.

Digestion of type I collagen with a collagenase-type protease yields a collagen tripeptide (Ctp) fraction comprising Gly-X-Y sequences that exhibit diverse biological activities. We previously demonstrated that Ctp inhibits the proliferation and migration of cultured aortic smooth muscle cells (SMCs) in vitro. These cells contribute to the pathogenesis of atherosclerosis and other cardiovascular diseases. In order to evaluate the effects of Ctp on atherosclerosis development in vivo, here we used the Kurosawa and Kusanagi-hypercholesterolemic (KHC) rabbit model of familial hypercholesterolemia to determine the effects of oral administration of Ctp for three months. Ctp induced a significant decrease in the area occupied by atherosclerotic plaques in the aorta and in the level of total serum cholesterol. The components of atherosclerotic plaques underwent distinct changes, including reduction in the populations of macrophages and SMCs and a significant decrease in the proportion of macrophages to SMCs. Ctp administration decreased the number of cells in plaques that expressed proliferating cell nuclear antigen and the number of cells with oxidative damage to DNA as indicated by 8-hydroxy-2'-deoxyguanine detection. These findings are the first to define the mechanism underlying the inhibitory effects of Ctp on atherosclerosis development in hypercholesterolemic rabbits, and suggest that Ctp provides an effective therapy for treating atherosclerosis.

Relationship of aquaporin 1, 3, and 5 expression in lung cancer cells to cellular differentiation, invasive growth, and metastasis potential.

An oncogenic capacity of aquaporins, transmembrane channels for water, was recently proposed. This study seeks to elucidate the involvement of aquaporin 1, 3, and 5 in the development and progression of lung cancer. Expression of aquaporin 1, 3, and 5 was examined by immunohistochemistry, Western blot, and laser-captured microdissection/real-time reverse transcription polymerase chain reaction in 160 lung cancers of various histologic subtypes; and its correlation with clinicopathological factors and survival was analyzed. Aquaporin 1, 3, and 5 were expressed in tumor cells in 71%, 40%, and 56% of lung cancers, respectively. Aquaporin expressions were frequent in adenocarcinomas, whereas aquaporin 1 and 5 were negative in squamous cell carcinomas. Bronchioloalveolar carcinoma cells exhibited an apicolateral aquaporin 1 and apicolateral or basolateral aquaporin 3 localization in nonmucinous type, and apical aquaporin 1 and 5 and basolateral aquaporin 3 expression in mucinous type, which corresponded to aquaporins expression of nonneoplastic lung tissue. Basolateral aquaporin 5 expression was acquired during tumorigenesis of nonmucinous bronchioloalveolar carcinoma. In contrast, invasive adenocarcinoma tumor cells overexpressed aquaporin 1 and 5 with loss of subcellular polarization and with an intracytoplasmic distribution. Overexpression of aquaporin 1 correlated with high postoperative adenocarcinoma metastasis ratios and unfavorable disease-free survival rates (P = .031). We conclude that expression patterns of aquaporin 1, 3, and 5 in lung cancer cells are mostly associated with cellular differentiation. However, the expression of aquaporin 1 and 5 is up-regulated in invading lung cancer cells, particularly in adenocarcinomas; and the overexpression of aquaporin 1 with loss of subcellular polarization is suggested to be involved in their invasive and metastatic potential.

Odontogenic myxofibroma with HMGA2 overexpression and HMGA2 rearrangement.

Odontogenic myxofibromas are variants of odontogenic myxomas that contain considerable amounts of collagen fibers in the myxoid stroma. Cytogenetic studies of odontogenic myxomas/myxofibromas have rarely been reported. This report describes the first case of an odontogenic myxofibroma presenting with HMGA2 protein overexpression and HMGA2 rearrangement in a 40-year-old woman. A 2.7-cm tumor in the premolar region of the right mandible was curettaged. There was no evidence of recurrence or metastasis at 12 months after the surgery. Histological examination revealed that the tumor comprised spindle or stellate cells with mild nuclear pleomorphism, abundant myxoid matrix and partly dense collagen fibers. Mitotic figures were rarely observed. Immunohistochemically, the tumor cells were diffusely positive for vimentin and HMGA2. Less than 1% of the tumor cells were positive for Ki-67. We detected split signals by interphase fluorescence in situ hybridization (FISH) in paraffin sections using HMGA2 break-apart probes. The breaks were certainly located within or near the HMGA2 gene. No rearrangement of the FUS gene was detected by FISH, implying discrimination from low-grade fibromyxoid sarcoma. It is suggested that HMGA2 rearrangement and HMGA2 protein overexpression may be associated with the tumorigenesis of odontogenic myxomas/myxofibromas, similar to the case for many other benign mesenchymal tumors.

Combined large cell neuroendocrine carcinoma and adenocarcinoma of the gallbladder.

Large cell neuroendocrine carcinoma (LCNEC) is a high-grade malignant neuroendocrine tumor that was first defined in the lungs. There are six previous reports on LCNEC in the gallbladder, comprising three cases combined with another tumor and three pure LCNECs. We describe a tumor combined with LCNEC and adenocarcinoma elements arising in the gallbladder and give a review of the literature. A 68-year-old woman was diagnosed as having gallbladder wall thickening and a hepatic mass. The surgically resected tumor had a dumbbell shape with gallbladder and liver elements. Histological examination revealed LCNEC in the liver and a deep infiltrative portion of the gallbladder, as well as a well-differentiated tubular adenocarcinoma in the mucosa of the gallbladder. The pseudoglandular structures of LCNEC were marked in the transitional area. Immunoreactivities for carcinoembryonic antigen and CA19-9 as well as for chromogranin A and synaptophysin were detected in the LCNEC element. High p53-protein expression and high proliferative activity estimated by Ki-67 positivity were observed in both elements. The results suggest a close relationship between LCNEC and adenocarcinoma, and support the theory that these elements originate from common cancer stem cells.

[Mixed epithelial and stromal tumor of the kidney: a case report].

We report a case of a mixed epithelial and stromal tumor of the kidney. A 64-year-old female who had no complaint was found to have a left renal tumor by computed tomography (CT) for an examination of a right breast tumor and was referred to our department. CT revealed a gradually enhancing 5 cm mass in the left kidney. The patient underwent left radical nephrectomy, and the tumor was histologically diagnosed as a mixed epithelial and stromal tumor. The patient has been followed up for 6 months with no evidence of local recurrence or metastasis.

Plasmacytoid urothelial carcinoma of the urinary bladder: a case report and immunohistochemical study.

We report a rare case of plasmacytoid urothelial carcinoma (PUC) of the urinary bladder. A 50-year-old man complained of pollakiuria and urinary incontinence. MRI detected a bladder tumor invading the rectum and bilateral hydroureteronephrosis. Radical cystectomy with partial resection of the rectum was performed, and ileus due to peritoneal dissemination occurred 2 years after surgery. He died of the disease 42 months after the initial presentation. Histologically, urothelial carcinoma in situ with a focal invasive urothelial carcinoma (IUC) component and widely spread PUC was observed. There was no lymph node metastasis. PUC cells had eccentrically placed nuclei and eosinophilic cytoplasm resembling plasmacytoma cells, and proliferated with a single-cell infiltrative pattern to the outside of the bladder. IUC cells with intracytoplasmic lumina were focally intermingled with PUC cells. Immunohistochemically, PUC cells were positive for cytokeratin 7, epithelial membrane antigen, and CA19-9, but negative for cytokeratin 20, E-cadherin, p63, and lymphoid markers. The Ki-67 labeling index of PUC cells was 9.3%. IUC containing intracytoplasmic lumina showed intermediate features of conventional IUC and PUC morphologically and immunohistochemically. PUC is a distinct entity of bladder cancer with a high propensity for invasion and poor prognosis.

Low-grade malignant soft-tissue perineurioma: interphase fluorescence in situ hybridization.

Perineuriomas are usually benign soft-tissue tumors that arise from perineurial cells of the peripheral nerve sheath. Low-grade malignant perineurioma is a rare type of perineurioma, presenting with infiltrative growth, low mitotic activity, and a lack of necrosis. This report describes a case of low-grade malignant perineurioma in a 60-year-old man who presented with a growing tumor on the dorsal side of his left wrist. The tumor was surgically excised and showed no adhesion to the surrounding muscle and no continuity with nerves. There was no evidence of recurrence or metastases 12 months after surgery. Histology indicated that the tumor contained hypercellular and hypocellular areas with spindle-shaped cells proliferating in storiform patterns or perivascular whorling. There was moderate infiltrative growth into the surrounding tissue. There was an evident central infarction but no coagulative necrosis. Mitotic figures were observed at 5/10 high-power fields. On immunohistochemistry tumor cells were found to be positive for epithelial membrane antigen, glucose transporter protein 1, and claudin-1. Approximately 18.4% of tumor nuclei were labelled for Ki-67. Interphase fluorescence in situ hybridization on paraffin sections indicated a loss of chromosome 13. This suggests that chromosome 13 abnormalities could also be involved in perineurioma with low-grade malignant potential.

Malignant epithelioid angiomyolipoma of the kidney in a patient with tuberous sclerosis: an autopsy case report with p53 gene mutation analysis.

We report an autopsy case of malignant epithelioid angiomyolipoma in a 36-year-old male tuberous sclerosis patient. He had been diagnosed to have a bilateral renal tumor 20 years previously. The left kidney had been surgically resected at the age of 34, and the left renal tumor was pathologically diagnosed as classic angiomyolipoma and epithelioid angiomyolipoma. He suddenly died of cardiac arrest, and at autopsy the right kidney weighed 7120 g. The tumor presented with massive necrosis invading the inferior vena cava, but was not hemorrhagic. Microscopic examination revealed tumor cells varying in size with a predominantly solid proliferation pattern and marked atypical large cells with vesicular nuclei and abundant eosinophilic cytoplasm. Mitotic figures were often encountered, and atypical forms were also present. Metastatic lesions were identified in the right lung, liver, diaphragm, and mesentery. Immunohistochemical examination showed epithelioid angiomyolipoma cells that were focally reactive for HMB-45 and showed diffuse positive staining for Melan-A. No mutation was detected in the p53 gene by polymerase chain reaction-single-strand conformation polymorphism (PCR-SSCP) analysis despite diffuse immunoreactivity for p53. This case was proven to be malignant because of the occurrence of distant metastases, and showed that p53 mutations are not always associated with malignant transformation in epithelioid angiomyolipoma.

Down-regulation of plakoglobin in soft tissue sarcoma is associated with a higher risk of pulmonary metastasis.

Soft tissue sarcomas (STS) behave with aggressiveness and metastatic potential, that can vary depending on their locations. There has been little information on the exact molecular mechanisms involved in their biological aggressiveness. To identify genes involved in the differences, the gene expression profiles were compared between STS-orthotopic and heterotopic implanted models, and their significance in human STS was verified. Human fibrosarcoma HT1080 cells were implanted either in the quadriceps femoris muscles or footpads of nude mice, and the gene expression profiles of the tumors were compared by cDNA arrays. The mRNA and protein levels of the identified genes were examined by both real time RT-PCR and immunohistochemistry not only in the tumors of the models, but also in clinical STS. The implanted HT1080 cells demonstrated different growth and metastatic potentials depending on their implant locations. cDNA array analyses showed decreased expression of the plakoglobin gene in the intramuscle-implanted group, which was statistically confirmed by real-time RT-PCR (p = 0.04). Plakoglobin was immunolocalized diffusely in the cytoplasm of tumor cells implanted in the footpads, but not those in the muscle. Real-time RT-PCR assays of clinical STS showed that the mean plakoglobin/glyceraldehyde 3-phosphate dehydrogenase (G3PDH) ratio in primary sarcoma tissues with pulmonary metastases (0.92) was significantly lower than in those without metastasis (6.58) (p < 0.0001), and that STS cases with high plakoglobin gene expression had an excellent prognosis. These results suggest that plakoglobin gene expression level might be useful as a new biomarker for metastasis and prognosis of human STS.

Amelioration of myocarditis by statin through inhibiting cross-talk between antigen presenting cells and lymphocytes in rats.

Statins, inhibitors of 3-hydroxy-3-methylglutary-coenzyme A (HMG-CoA) reductase, have been recognized as a new type of immunomodulator and reported to have anti-inflammatory effect. To investigate the effect of simvastatin, a lipophilic statin, on myocarditis, we explored whether simvastatin is able to inhibit experimental autoimmune myocarditis (EAM) and adoptive transfer of EAM in rats. We found that administration of simvastatin not only interfered with the development of EAM, but also inhibited the transfer. Antigen presenting cells (APCs) were proved to be important for the development of EAM. The ability of myocarditic splenocytes to transfer myocarditis was enhanced after co-culture with APCs. During co-culture of the myocarditic splenocytes and the APCs, simvastatin not only decreased percentages of CD28 expression in CD4-positive myocarditic splenocytes, and CD80 and CD86 expressions in APCs, but also inhibited the production of tumor necrosis factor (TNF)-partial differential in the CD4-positive myocarditic splenocytes and the APCs. These results indicate that simvastatin was able to ameliorate EAM through the inhibition of cross-talk between lymphocytes and APCs, suggesting beneficial role of simvastatin in the treatment of autoimmune myocarditis.

Thyroid adenomatous nodule with bizarre nuclei: a case report and mutation analysis of the p53 gene.

We present a rare case of adenomatous nodule with bizarre nuclei. The patient was incidentally found to have a nodule in the left lobe of the thyroid gland by ultrasonographic examination. Papillary thyroid carcinoma was suspected by fine needle aspiration cytology, and hemithyroidectomy was performed. The demarcated 1.5-cm nodule had a multinodular appearance with various features, including micro- and macrofollicular components, cystic degeneration, a hyalinized area, and a papillary structure. Hyperchromatic bizarre nuclei with cytoplasmic inclusions were restrictively observed in the microfollicular area. The bizarre nuclei demonstrated diffuse p53 protein immmunoreactivity, but no mutation in exons 5-9 of the p53 gene was detected. The bizarre nuclei were reactive for anti-5-methyl-2'-deoxycytidine antibody, indicating the enclosure of presumably inactive methylated DNA. The intranuclear cytoplasmic inclusions (ICIs) were proven to contain vimentin and beta-catenin by immunohistochemistry. In this case, a degenerative process is involved in the formation of bizarre nuclei because of the compression by surrounding micronodules, unidentifiable mitotic figures, and a quite low proliferative activity. This case suggests that bizarre nuclei and ICIs, which might be identical to those of papillary carcinomas, can be seen in benign thyroid lesions, and overdiagnosis should be avoided regardless of immunohistochemical overexpression of p53.

Involvement of thymus in amiodarone-treated autoimmune myocarditis in rats.

We previously showed that amiodarone, an iodine-rich benzofuranic derivative, interferes with the progression of myocarditis using a rat model of experimental autoimmune myocarditis. Further studies have also revealed that intraperitoneal treatment with 12.5 mg/kg amiodarone, which is below the range of its therapeutic plasma concentration, also effectively interferes with the progression of myocarditis using the same model. The relationship between myocarditis and the thymus has not been studied in either patients or animal models. To investigate whether the thymus is involved in the effect of amiodarone on experimental autoimmune myocarditis, we examined its phenotypic distribution in thymocytes and peripheral blood lymphocytes using flow cytometry. We found no significant differences in the proportions of CD4(+) and CD8(+) T cells and the CD4(+)/CD8(+) T cell ratio in the control group compared with amiodarone-treated group. However, amiodarone-treated group induced a decrease in the proportion of CD4(+)TNF(+) and CD4(+)IL-4(+) T cells and an increase in CD4(+)IFN(+) T cells, resulting in a significant reduction of the CD4(+)TNF(+)/CD4(+)IFN(+) and CD4(+)IL-4(+)/CD4(+)IFN(+) T cell ratios. These results suggest for the first time that the thymus is actively involved when myocarditis is treated with amiodarone.

Expression of matrix metalloproteinases in wound healing after glaucoma filtration surgery in rabbits.

PURPOSE: To investigate the protein and mRNA expressions of matrix metalloproteinases (MMPs), gelatinolytic activity and localization of MMP activity in wounds after glaucoma filtration surgery in rabbits. METHODS: Sixty eyes of 30 rabbits were removed 1, 3, 7, 14 and 120 days after the surgery and used for this experiment. Protein and mRNA expressions were analyzed by immunohistochemistry and laser capture microdissection/real-time RT-PCR, respectively. The gelatinolytic activity was analyzed by gelatin zymography and the localization was studied using in situ zymography. RESULTS: By immunohistochemistry, expression of MMP-1, MMP-2, MMP-3, MMP-9 and MT1-MMP was detected in the wounds, most markedly 3 days after the surgery. MMP-positive cells were predominantly macrophages. Expression of MMP-9 and MT1-MMP mRNAs was verified by RT-PCR. Gelatinolytic activities corresponding to proMMP-2 and the active form of MMP-2 were detected in the wounds 3 and 7 days after surgery. In situ zymography localized gelatinolytic activities at the wound site. These activities were almost completely abolished by an MMP inhibitor, indicating that the gelatinolytic activity belongs to metalloproteinases. CONCLUSIONS: MMPs, particularly MMP-2/MT1-MMP, play important roles in the degradation of the extracellular matrix in the wound healing process after glaucoma filtration surgery and may represent an important target for therapeutic intervention after glaucoma filtration surgery.

Fasciitis ossificans of the breast.

We report a rare case of fasciitis ossificans of the breast. A nodule of the breast was incidentally found in a 77-year-old woman without a history of trauma. The painless lesion was located 3 cm from the nipple in the lower outer quadrant of the left breast. Excisional biopsy was performed, and there has been no evidence of recurrence or metastasis for 2 years. The 1.8 cm diameter nodule was well demarcated from the adjacent tissue and located 2.5 cm beneath the skin. Histologically, the lesion was composed of uniform woven bone trabeculae with rimming of osteoblasts and fibrous stroma. At the periphery, spindle cells actively proliferated in edematous stroma, demonstrating uniform nuclei without increased chromatin, pleomorphism, or evident nucleoli. We counted 2 mitotic figures per 10 high-power fields, but no atypical forms were observed. Spindle cells were immunoreactive for vimentin and alpha-smooth muscle actin, suggesting myofibroblastic differentiation. Fasciitis ossificans is histologically identical to myositis ossificans, but tends to present no zonation phenomenon. We considered this lesion as fasciitis ossificans since it was situated at the superficial layer of the mammary gland. To avoid an unnecessarily aggressive treatment, fasciitis ossificans, a benign bone-forming nodule, needs to be considered in the differential diagnosis of breast hard tumor.

Extrauterine endometrial stromal sarcoma with JAZF1/JJAZ1 fusion confirmed by RT-PCR and interphase FISH presenting as an inguinal tumor.

Endometrial stromal sarcomas are rare malignant mesenchymal tumors that usually develop in the uterine corpus and occasionally arise at various extrauterine sites. This report describes the first case of primary extrauterine endometrial stromal sarcoma arising in the extraperitoneal portion of the round ligament presenting as a solitary inguinal mass in a 46-year-old woman. The patient presented gradually growing tumor in the right inguinal region. Local tumor resection was performed and no recurrence or metastasis was found at 15 months after the operation. Histological examination revealed that the tumor comprised uniform, spindle-shaped cells with blunt nuclear figure and scattered small arteries, and infiltrated into adjacent tissue. No endometriosis was morphologically identified in the lesion. Immunohistochemically, the tumor cells were positive for CD10, estrogen receptor, progesterone receptor, alpha-smooth muscle actin, and calponin. We confirmed JAZF1/JJAZ1 fusion by reverse transcription-polymerase chain reaction and the corresponding chromosomal translocation by interphase fluorescence in situ hybridization on paraffin sections. It is essential that the inguinal region should be recognized as a possible primary site of endometrial stromal sarcoma, and the detection of a JAZF1/JJAZ1 fusion can be useful when the diagnosis is not confirmed by microscopic observation or immunohistochemistry for the tumor arising in extrauterine sites.