Inhibition of heat shock protein 90 exerts an antitumour effect in angiosarcoma: involvement of the vascular endothelial growth factor signalling pathway.

BACKGROUND: Angiosarcoma is a rare malignant neoplasm derived from endothelial cells, and because advanced angiosarcoma is resistant to standard chemotherapy its prognosis is poor. Therefore, new therapies are urgently needed. Heat shock protein (HSP)90 has been identified as a molecular chaperone that regulates various cancer-related proteins. Numerous clinical trials are currently testing the effectiveness of HSP90 inhibitors in various types of malignancies. OBJECTIVES: To investigate the role of HSP90 in the pathogenesis of angiosarcoma and whether the inhibition of HSP90 may have antitumour activity. METHODS: The expression of HSP90 protein in angiosarcoma was examined using immunohistochemistry and immunoblotting. The effects of HSP90 inhibition were proven using proliferation, migration and invasion assay in angiosarcoma cells. The mechanism of antitumour effect by HSP90 inhibition was investigated by the transfection of small interfering RNA (siRNA). RESULTS: The levels of HSP90 protein expression in cultured angiosarcoma cell lines were markedly increased compared with those in normal tissue cell lines. Immunohistochemical analyses revealed that the expression of HSP90 protein was strongly detected in angiosarcoma tissues compared with that in normal dermal vessels or senile angioma tissues. Ganetespib, an HSP90 inhibitor, with or without taxanes, inhibited the proliferation of angiosarcoma cells via apoptosis in a dose-dependent manner. HSP90 siRNA suppressed the proliferation, migration and invasion of angiosarcoma cells. Knock-down of HSP90 did not suppress vascular endothelial growth factor receptor 2 directly, but selectively suppressed several downstream targets of vascular endothelial growth factor signalling in angiosarcoma cells. CONCLUSIONS: HSP90 could be a novel therapeutic target for angiosarcoma.

Chlamydophila pneumoniae Infection Induced Nodular Vasculitis.

We present the case history of a 48-year-old male patient with Chlamydophila (Chlamydia) pneumoniae who developed a nodular vasculitis. He developed a cutaneous vasculitis with the onset of respiratory symptoms. The diagnosis of Chlamydophila pneumoniae infection was based on serology. Since this infection is very common in our population, although often asymptomatic, it should be systematically considered as a causative agent of nodular vasculitis.

Comprehensive MR imaging of acute gynecologic diseases.

Rapid advances in techniques of magnetic resonance (MR) imaging have enabled diagnosis of acute gynecologic conditions, which are characterized by sudden onset of lower abdominal pain, fever, genital bleeding, intraperitoneal bleeding, or symptoms of shock. The chemical-selective fat-suppression technique not only helps establish the characteristics of lesions that contain fat components but also increases the conspicuity of inflammatory lesions. When a T2-weighted image is obtained with a very long effective echo time (>250 msec), even a small amount of ascites can be easily identified and the contrast between urine and complex fluid becomes more conspicuous. T2*-weighted images are useful for identification of hemorrhagic lesions by demonstrating deoxyhemoglobin and hemosiderin. Contrast material-enhanced dynamic subtraction MR imaging performed with a three-dimensional fast field-echo sequence and a rapid bolus injection of gadopentetate dimeglumine allows evaluation of lesion vascularity and the anatomic relationship between pelvic vessels and a lesion and allows identification of the bleeding point by demonstrating extravasation of contrast material. To optimize the MR imaging examination, attention should be given to the parameters of each pulse sequence and proper combination of the sequences.

Pathology of ALY mice: congenital immunodeficiency with lymph node and Peyer's patch defects.

The ALY-alyl/aly mouse is a new and unique animal model of primary immunodeficiency with autosomal recessive inheritance. The ALY mouse is devoid of superficial and profound lymph nodes and Peyer's patches. Furthermore, the lymphoid follicles and marginal zones are not clearly identified in the spleen. In addition to these structural defects, in the present study, we show that some B subpopulations are defective. Firstly, the thymic B lymphocytes are very rare. Secondly, the B220hi sIghi B subpopulation in the bone marrow is not detected as a clear cluster on FACS analyses. Thirdly, the B220 slg+ cells in the bone marrow are very rare in both ALY-aly/aly and ALY-alyl+ mice. By contrast, the NK activity is normal. Taken together, the ALY mouse is an invaluable model to elucidate the immunological networks between the lymphoid structures (lymph nodes, Peyer's patches, lymphoid follicles, etc.) and functions.

Scrotal disorders: evaluation of testicular enhancement patterns at dynamic contrast-enhanced subtraction MR imaging.

PURPOSE: To evaluate testicular enhancement patterns in various scrotal disorders at dynamic contrast medium-enhanced subtraction magnetic resonance (MR) imaging. MATERIALS AND METHODS: Forty-two patients with scrotal symptoms (22 testicular diseases, 20 extratesticular scrotal disorders) underwent three-dimensional (3D) fast field-echo or fast spin-echo dynamic subtraction MR imaging after injection of paramagnetic contrast medium. The relative percentages of peak height and mean slope of the testes on the affected side were compared with those on the unaffected side by using time-signal intensity curves. RESULTS: Extratesticular scrotal disorders (time-signal intensity curve mean peak height, 93.1%; mean slope, 89.8%) showed gradual and progressive increase in homogeneous testicular contrast enhancement in all normal testes. Relative percentages of peak height and mean slope of testicular torsion (mean peak height, 17.3%; mean slope, 10.6%), infarction (mean peak height, 30.4%; mean slope, 19.8%), traumatic hemorrhagic necrosis (mean peak height, -3.5%; mean slope, -12.0%), and epidermoid cyst (mean peak height, -6.6%; mean slope, -14.2%) were significantly lower than those of extratesticular scrotal disorders. Acute mumps orchitis (mean peak height, 135.1%; mean slope, 307.5%) and malignant testicular tumor (mean peak height, 178.7%; mean slope, 467.6%) showed higher relative percentages of peak height and mean slope. CONCLUSION: Dynamic contrast-enhanced subtraction MR imaging can provide information about testicular perfusion on the basis of contrast enhancement and can be used to differentiate testicular diseases from scrotal disorders.

Hypercoagulopathy with piperacillin administration in osteomyelitis.

A 51-year-old man with osteomyelitis developed acute renal failure and superior mesenteric venous (SMV) thrombosis after piperacillin (PIPC) treatment. Coagulation profile disclosed disseminated intravascular coagulation (DIC). The serum levels of IgE and eosinophil cationic protein showed significant increases, while a lymphocyte stimulation test with PIPC also demonstrated an extremely high index. These observations suggest that hypersensitivity to PIPC might play a role in the pathogenesis of acute renal failure and SMV thrombosis due to hypercoagulopathy. Withdrawal of PIPC and anticoagulation therapy resulted in clinical improvement and normalization of the affected laboratory data. This is the first report to describe PIPC-induced hypercoagulopathy.

Pseudo-obstruction of the extrahepatic bile duct due to artifact from arterial pulsatile compression: a diagnostic pitfall of MR cholangiopancreatography.

PURPOSE: To evaluate the frequency of artifact from arterial pulsatile compression as the cause of pseudo-obstruction of the extrahepatic bile duct at magnetic resonance (MR) cholangiopancreatography (MRCP) and specify the causative vessels. MATERIALS AND METHODS: In 234 patients (102 men, 132 women; age range, 25-80 years), MRCP images obtained by using a single-shot turbo spin-echo sequence were reviewed to assess pseudo-obstruction of the extrahepatic bile duct caused by vascular compression. Dual-phase spiral computed tomography, contrast material-enhanced three-dimensional MR angiography, and/or digital subtraction angiography also were performed to determine the vessel that caused the pseudo-obstruction. RESULTS: Thirty-six pseudo-obstructions due to vascular compression were found in 33 (14%) patients. The common hepatic duct (27 [75%] sites) was the most common pseudo-obstruction site, followed by the left hepatic duct (four [11%] sites), proximal common bile duct (three [8%] sites), and right hepatic duct (two [6%] sites). The causative vessels were identified as the right hepatic artery at 24 (67%) sites; gastroduodenal artery, two (6%) sites; cystic artery, two (6%) sites; proper hepatic artery, one (3%) site; and an unspecified branch of the common hepatic artery, seven (19%) sites. CONCLUSION: At MRCP, pseudo-obstruction of the extrahepatic bile duct can be caused by pulsatile vascular compression of the hepatic and gastroduodenal arteries, and it should not be misdiagnosed as a bile duct tumor or biliary stone.

Dynamic subtraction contrast-enhanced MR angiography: technique, clinical applications, and pitfalls.

Rapid advances in techniques of contrast material-enhanced magnetic resonance (MR) angiography have enabled evaluation of the entire aorta and the main arteries. Dynamic subtraction MR angiography consists of first-pass imaging of long segments of arteries by using a three-dimensional fast field echo sequence with multiple rapid bolus injections of a small dose of gadopentetate dimeglumine. Subtraction enables clear demonstration of the enhanced vascular lumen by eliminating background signal. Improved temporal resolution and repeated sequences after gadopentetate dimeglumine administration allow demonstration of arteries and veins separately. Double subtraction postprocessing can be used to eliminate arterial enhancement in demonstration of the portal and systemic veins. Additional postprocessing can be used to demonstrate arteries in a single image in patients with aortic dissection or a prolonged circulation time. To optimize the examination, the pulse sequence, injection dose, injection rate, timing of the start of data acquisition, imaging time, breath holding, section thickness, and coil selection should be considered. This technique is flexible enough to be applied in a variety of clinical settings, including atherosclerotic occlusive disease, aneurysm of aortoiliac arteries, bypass graft, Takayasu arteritis, aortic dissection, antiphospholipid antibody syndrome, renal artery disease, pelvic vascular disease, and the portomesenteric venous system.

Age-dependent abnormalities of hematopoietic stem cells in (NZW x BXSB)F1 mice.

The (NZW x BXSB)F1 (W/BF1) mouse is known as an autoimmune-prone strain which develops lupus nephritis, thrombocytopenia due to platelet-specific autoantibodies, leukocytosis, and myocardial infarction. In this experiment, we investigated the age-dependent abnormalities of the hematopoietic stem cells (HSCs) and hematopoiesis in this mouse. White blood cell counts (especially Mac-1- or Gr-1-positive cells) in the peripheral blood of 12-week-old W/BF1 mice increased in comparison with those of four-week-old W/BF1 or normal mice. To investigate whether the abnormal hematopoiesis can be attributed to the HSCs of W/BF1 mice, colony-forming unit in spleen (CFU-S) and colony-forming unit in culture (CFU-C) assays were performed. Day 12 CFU-S counts of 12-week-old W/BF1 mice significantly increased in comparison with those of four-week-old W/BF1 mice or normal mice. In the CFU-C assay, CFU-GEMM and CFU-GM counts in 12-week-old W/BF1 mice increased in comparison with those of four-week-old W/BF1 or control mice. The bone marrow cells (BMCs) from 12-week-old W/BF1 mice showed a high level of G-CSF and a low level of GM-CSF in mRNA expression. To examine the effect of HSCs from 12-week-old W/BF1 mice on the onset of autoimmune diseases and the abnormal hematopoiesis, T- and B-cell-depleted BMCs of four-week-old or 12-week-old W/BF1 mice were transplanted to C3H mice. Recipient C3H mice that had received the BMCs from 12-week-old W/BF1 mice showed an earlier onset of autoimmune diseases and a shorter survival rate than those that had received the BMCs from four-week-old W/BF1 mice. These data suggest that the HSCs from 12-week-old W/BF1 mice showing the symptoms of autoimmune diseases have the capacity to induce autoimmune diseases earlier than the HSCs from four-week-old W/BF1 mice.

Identification of thorotrast by gamma-spectrometry and simplified autoradiography in pathological specimens.

Simplified and reliable methods for identifying thorotrast are demonstrated. On gamma-ray spectrometry, as little as 0.1 g of liver tissue gives gamma-ray spectrum characteristics to the thorium decay series, despite a low net count. When conventional film for photography is kept in contact with a paraffin section of the liver for 4 months, it develops silver grains exactly corresponding to the area of granular deposition. By combining this method with clinical and pathological findings, a diagnosis of thorotrastosis can be established without the need for special instruments or materials.

Contrast-enhanced three-dimensional MR portography.

Three-dimensional (3D) magnetic resonance (MR) portography with contrast material enhancement is a fast means of evaluating the portal venous system that has some advantages over currently used modalities, such as digital subtraction angiography, helical computed tomography, ultrasonography, and nonenhanced MR angiography with time-of-flight and phase-contrast techniques. With contrast-enhanced 3D MR portography, a first-pass study of the mesenteric vasculature is performed after rapid bolus injection of gadopentetate dimeglumine; a 3D fast field echo sequence is used, which can demonstrate the intrahepatic and extrahepatic portal venous system clearly. Repeated sequences after administration of gadopentetate dimeglumine allow separate demonstration of the splanchnic arteries and portomesenteric veins. The images are reconstructed by means of maximum-intensity projection postprocessing, and a subtraction technique can be used to eliminate arterial enhancement and demonstrate portosystemic shunts. The coronal source images simultaneously demonstrate parenchymal lesions of the liver, pancreas, biliary tract, and spleen. This technique is clinically indicated in portosystemic shunt, portal vein thrombosis, hepatocellular carcinoma, pancreatobiliary tumor, hepatic vein obstruction, differentiation of splanchnic arterial from portal venous disease, and gastrointestinal hemorrhage. Its limitations include allergic reactions to contrast media, inappropriate positioning of the 3D acquisition slab, respiratory motion artifacts, and pseudodissection.

Down-regulation of TGF-beta receptors in human colorectal cancer: implications for cancer development.

Many colorectal cancer cells are resistant to the anti-proliferative effects of transforming growth factor-beta (TGF-beta). TGF-beta also acts as paracrine factor from cancer cells on their mesenchymal cells. The aim of this study was to examine the expression of TGF-beta and its receptors in human colorectal cancer tissue and determine any relationship with cancer growth. In situ hybridization and Northern blot hybridization detection of TGF-beta1, type I and type II receptor mRNA and immunohistochemical staining of TGF-beta1 were performed using 11 human colorectal adenomas, 22 colorectal cancers and ten normal colorectal mucosas as control. TGF-beta receptor mRNAs were expressed mainly by normal colorectal epithelial cells and adenoma. However, mRNAs for TGF-beta receptors were only faintly, if at all, expressed in eight of 22 human colorectal cancers. In addition, intense signals of TGF-beta1 mRNA and the protein were detected in all colorectal cancers. TGF-beta receptor mRNAs and TGF-beta1 protein were also distributed in fibroblasts and endothelial cells in the interstitium. Moreover, Smad 4 protein was translocated to nucleus in primarily cultured adenoma cells, but not in cancer cells after TGF-beta stimulation. The escape of human colon cancer from TGF-beta-mediated growth inhibition by down-regulation of TGF-beta receptors as well as the effects of TGF-beta on stroma formation and angiogenesis indicate a possible role for TGF-beta in the progression of colon cancer in an intact host.

Increased neutrophil chemotaxis in obstructive jaundice: an in vitro experiment in rats.

BACKGROUND AND AIMS: Changes in neutrophil functions in obstructive jaundice have been poorly understood. An in vitro experimental study was performed to evaluate the effect of obstructive jaundice on the functions of macrophages (secretion of neutrophil chemoattractants) and neutrophils (chemotaxis and superoxide anion generation). METHODS: Obstructive jaundice was produced in rats by 7 day bile duct ligation. Peripheral neutrophils and peritoneal macrophages were harvested from either normal, sham-ligated or bile duct-ligated rats and supernatants of the monolayers of the respective macrophages were prepared after stimulation with lipopolysaccharide. Neutrophil chemotaxis was evaluated with a modified Boyden method. RESULTS: The supernatant of the bile duct-ligated rat macrophages showed a chemotactic effect on normal rat neutrophils with insignificant difference from the supernatant of the sham-ligated rat macrophages. Chemotaxis of the bile duct-ligated rat neutrophils towards the supernatant of the normal rat macrophages was significantly increased, compared with that of sham-ligated rat neutrophils. Similarly, neutrophils from bile duct-ligated rats showed significantly greater chemotaxis to formyl-methionyl-leucyl-phenylalanine than the sham-ligated rat neutrophils. Superoxide anion generation in response to formyl-methionyl-leucyl-phenylalanine or phorbol myristate acetate was significantly increased in the bile duct-ligated rats compared with the sham-ligated rats. CONCLUSIONS: The results suggest that the neutrophil is primed in terms of chemotaxis and superoxide anion generation in obstructive jaundice. How these activated neutrophils play a role in the inflammatory response to obstructive jaundice should be evaluated.

Diagnostic pitfalls of MR cholangiopancreatography in the evaluation of the biliary tract and gallbladder.

Magnetic resonance (MR) cholangiopancreatography is a noninvasive imaging technique that has proved accurate in the diagnosis of biliary obstruction. However, various diagnostic pitfalls have been reported with MR cholangiopancreatography that were not encountered previously at conventional biliary imaging. These pitfalls may simulate or mask various pathologic conditions of the extrahepatic bile duct or main pancreatic duct and may be caused by a variety of factors. Because of its postprocessing nature, maximum-intensity-projection reconstruction may mask a small gallstone if the stone is surrounded by hyperintense bile and may cause false ductal disconnection or duplication when a breath hold is not performed perfectly. Extraductal factors (e.g., metallic surgical clips, intravascular metallic coils, gas in the stomach or duodenum) can cause signal loss in the adjacent part of the extrahepatic bile duct, which may in turn lead to a false-positive diagnosis of ductal narrowing or obstruction. Normal vascular structures including the right hepatic and gastroduodenal arteries can cause pseudo-obstruction of the extrahepatic bile duct by pulsatile compression. Intraductal factors (e.g., gas, hemorrhage, debris, iodinated contrast material) reduce the signal intensity of the bile, which may result in pseudo-obstruction, false filling defects, or a nonvisualized gallbladder or bile duct. Knowledge of the existence and high prevalence of these diagnostic pitfalls should help prevent misinterpretation of MR cholangiopancreatograms.

[Clinical usefulness of fat suppression technique for MR cholangiopancreatography (MRCP)].

In order to obtain high quality of MRCP image, it is important to reduce the background signal intensity and increase the contrast of the pancreatobiliary ducts relative to surrounding fat tissue. The combination of long effective-TE and fat suppression technique including the short-TI inversion recovery and chemical-selective fat suppression enables to suppress the background signal intensity enough to obtain high quality MR cholangiopancreatogram. However, susceptibility artifacts from the metal, gastroduodenal gas, and vascular pulsation can be augmented by using the chemical-selective fat suppression technique, which may result in signal loss of the pancreatobiliary ducts. This potential diagnostic pitfalls can be avoided by interpreting the coronal source images obtained with long effective-TE and without fat suppression technique.

Influence of biliary obstruction on neutrophil chemotaxis.

The effect of obstructive jaundice on neutrophil chemotactic function was investigated, with a potent chemotactic factor, IL-8 (recombinant rat GRO-beta), in rats that received 7-day bile duct ligation. Carrageenin or IL-8 was injected into a preformed air pouch, and exudate was collected 4 h later for measurement of myeloperoxidase activity. In vitro chemotaxis of peripheral neutrophils to IL-8 was evaluated by a modified Boyden chamber method. Both carrageenin and IL-8 induced significantly pronounced intra-air pouch neutrophil recruitment in the bile duct-ligated group compared with a sham-ligated group. In vitro neutrophil chemotaxis was significantly increased in the bile duct-ligated group compared with the sham-ligated group. The present experimental model suggests enhanced neutrophil chemotaxis to IL-8 in obstructive jaundice.

High-resolution MR cholangiopancreatography.

1. High-resolution MRCP is a noninvasive imaging modality for depicting the pancreatobiliary tree. The imaging quality of high-resolution MRCP is satisfactory. MRCP can demonstrate dilation, stenosis, and intraductal filling defects of both the biliary tract and the pancreatic duct, which meets the clinical demand for pancreatobiliary imaging. 2. MRCP was successful in almost all the patients. However, the causes of MRCP failure were patient motion, irregular respiratory rhythm, severe pneumobilia, and massive ascitic fluid. 3. When only MIP reconstructed images were used for interpretation, small intraductal filling defects such as a gallstone can be missed. In combination with coronal source images, the ability to detect intraductal stones can be increased. 4. Ferrite ammonium citrate (FAC) is useful in suppressing the background signal intensity of gastrointestinal contents so that the ducts can be clearly visualized. The other technique for decreasing the background signal intensity is target MIP postprocessing, which works well for better visualization of the ducts. 5. The degree of ductal narrowing tends to be overestimated with MRCP because of MIP reconstruction artifact and lower spatial resolution of MRCP than ERCP. 6. MRCP has a diagnostic pitfall of a pseudostenosis of extrahepatic ducts, which may lead to a false-positive diagnosis of ductal narrowing. This pitfall may be caused not only by MIP postprocessing artifacts but by gas, surgical metal, and vascular compression of right hepatic artery. There is another diagnostic pitfall that it is difficult to differentiate intraductal mucin from pancreatic fluid in dilate pancreatic ducts, although ERCP identifies mucin as intraductal filling defects.

Effects of administration of monoclonal antibodies (anti-CD4 or anti-CD8) on the development of autoimmune diseases in (NZW x BXSB)F1 mice.

(NZW x BXSB)F1 (W/BF1) mice spontaneously develop autoimmune diseases, characterized by lymphadenopathy, lupus nephritis, and immune thrombocytopenia associated with various autoantibodies such as anti-DNA, anti-platelet and anti-cardiolipin antibodies (Abs). In the present study, we investigate the effects of administration of monoclonal Abs (anti-CD4 or anti-CD8 mAb) on the development of autoimmune diseases in W/BF1 mice. MAb was administered from the age of 7 weeks. Prolongation of survival rate and reduction of severity of autoimmune diseases were observed after treatment with anti-CD4 mAb. However, anti-CD8 mAb treatment accelerated the diseases. Serum levels of IFN-gamma and IL-10 in old W/BF1 mice were significantly high, whereas IL-4 levels were low in comparison with those of young W/BF1 mice; the expression of mRNA of IFN-gamma, IL-4 or IL-10 in CD4+ T cells of old W/BF1 mice was parallel to the serum levels of each cytokine. These observations suggest that CD4+ cells are involved in the development of autoimmune diseases in W/BF1 mice, and that CD8+ cells have a suppressive effect on the development of autoimmune diseases in W/BF1 mice.