Prognostic significance of Bcl-xL in human hepatocellular carcinoma

BACKGROUND: Proliferation and apoptosis of liver cancer cells are closely related phenomena. We investigated the correlation between overexpression of Bcl-xL, an anti-apoptosis-related protein of the Bcl-2 family, and the clinical course of hepatocellular carcinoma (HCC). METHODS: Specimens from 7 HCC patients were used for Western blotting and immunoelectron microscopy tests. Samples from 33 HCC patients who had undergone hepatectomies were used for immunohistochemical staining. The degrees of expression of Bcl-xL and Ki-67, as an index of HCC mitosis severity, were each classified into 2 groups. RESULTS: With the use of Western blot analysis, enhanced immunoreactivity of Bcl-xL was found in cancerous specimens. Bcl-xL overexpression was found in cancer specimens in 21 of 33 patients (63.6%). The overall survival (P=.019) and disease-free survival (P=.030) rates of the group overexpressing Bcl-xL were definitely poorer. The Ki-67 higher labeling index LI > 10) group had a poorer survival rate (P=.016). There were significant correlations between Bcl-xL and overall survival and disease-free survival. Multivariate analyses revealed that Bcl-xL, tumor size, histologic portal invasion, and histologic metastatic foci were independent prognostic factors for overall survival and disease-free survival. CONCLUSIONS: These results showed Bcl-xL in HCC specimens, suggesting that Bcl-xL was a significant prognostic factor for disease progression in human HCC.     

Role of the dorsolateral pontine nucleus in short-term adaptation of the horizontal vestibuloocular reflex

The dorsolateral pontine nucleus (DLPN) is a major component of the cortico-ponto-cerebellar pathway that carries signals essential for smooth pursuit. This pathway also carries visual signals that could play a role in visually guided motor learning in the vestibular ocular reflex (VOR). However, there have been no previous studies that tested this possibility directly. The aim of this study was to determine the potential role of the DLPN in short-term VOR gain adaptation produced by viewing a scene through lenses placed in front of both eyes. In control experiments, adaptation of VOR gain was achieved by sinusoidal rotation (0.2 Hz, 30 degrees /s) for 2 h while the monkey viewed a stationary visual surround through either magnifying (x2) or minifying (x0.5) lenses. This led to increases (23-32%) or decreases (22-48%) of VOR gain as measured in complete darkness (VORd). We used injections of muscimol, a potent GABA(A) agonist (0.5 microl; 2%), to reversibly inactivate the DLPN, unilaterally, in three monkeys. After DLPN inactivation, initial acceleration of ipsilateral smooth-pursuit was reduced by 35-68%, and steady-state gain was reduced by 32-61%. Despite these significant deficits (P < 0.01) in ipsilesional smooth pursuit, the VOR during lens viewing was similar to that measured in preinjection control experiments. Similarly, after 2 h of adaptation, VORd gain was not significantly different (P > 0.61) from control adaptation values for either ipsi- or contralesional directions of head rotation. This was the case even though a stable ipsilesional smooth pursuit deficit persisted throughout the full adaptation period. Our results suggest that visual error signals for short-term adaptation of the VOR are derived from sources other than the DLPN perhaps including other basilar pontine nuclei and the accessory optic system.     

Severe secondary deficiency of von Willebrand factor-cleaving protease (ADAMTS13) in patients with sepsis-induced disseminated intravascular coagulation: its correlation with development of renal failure

Deficiency of ADAMTS13 is found in patients with thrombotic thrombocytopenic purpura (TTP), and the genetic defects in the ADAMTS13 gene or the autoantibody against ADAMTS13 is thought to be responsible for the development of TTP. The clinical correlation and mechanisms of secondary ADAMTS13 deficiency in other disease states were investigated. In addition to TTP, ADAMTS13 levels were severely decreased in patients with sepsis-induced disseminated intravascular coagulation (DIC). The incidence of acute renal failure and serum creatinine levels in patients with ADAMTS13 activity levels lower than 20% (incidence, 41.2%; creatinine, 160 +/- 150 microM [1.81 +/- 1.70 mg/dL]) (P < .05) were significantly higher than they were in patients with ADAMTS13 activity levels higher than 20% (incidence, 15.4%; creatinine, 84 +/- 67 microM [0.95 +/- 0.76 mg/dL]) (P < .01). Additionally, unusually large von Willebrand factor multimers were detected in 26 (51.0%) of 51 patients with ADAMTS13 activity levels lower than 20%. Lower molecular weight forms of ADAMTS13 were found in the plasma of patients with sepsis-induced DIC, suggesting that the deficiency of ADAMTS13 was partially caused by its cleavage by proteases in addition to decreased synthesis in the liver. These data suggested that severe secondary ADAMTS13 deficiency can be associated with sepsis-induced DIC and may contribute to the development of renal failure.     

Hepatic metastases: diffusion-weighted sensitivity-encoding versus SPIO-enhanced MR imaging

PURPOSE: To retrospectively compare accuracy of diffusion-weighted (DW) single-shot echo-planar imaging with sensitivity encoding (SENSE) with that of superparamagnetic iron oxide (SPIO)-enhanced magnetic resonance (MR) imaging in the evaluation of hepatic metastases due to extrahepatic malignancies. MATERIALS AND METHODS: Patients provided informed consent; ethics committee approval was not required. The data of 24 patients (16 men, eight women; age range, 41-68 years; mean age, 61.9 years) with 40 resected hepatic metastases were retrospectively reviewed. Before SPIO administration, DW SENSE imaging and T2-weighted fast spin-echo (SE) and T1-weighted dual-echo fast field-echo (FFE) MR imaging were performed. After SPIO administration, T2-weighted fast SE, T1-weighted dual-echo, and T2*-weighted FFE MR examinations were performed. Images were divided into two sets: The SPIO-enhanced MR image set consisted of pre- and postcontrast T2-weighted fast SE and dual-echo T1-weighted FFE images and postcontrast T2*-weighted FFE images. The DW SENSE image set included DW SENSE images and precontrast T2-weighted fast SE and dual-echo T1-weighted FFE images. Three radiologists individually interpreted these images and sorted the confidence levels for presence of hepatic metastasis in each section into five grades. Area under the receiver operating characteristic (ROC) curve (A(z)) was calculated for each image set. RESULTS: Hepatic metastases showed higher signal intensity on DW SENSE images than on T2-weighted fast SE images. Conversely, signals from vessels and cysts were suppressed with DW SENSE imaging. ROC analysis showed higher A(z) values when the DW SENSE image set was interpreted (0.90) than when the SPIO-enhanced MR image set was interpreted (0.81). The sensitivity and specificity, respectively, of total cases were 0.66 and 0.90, for the SPIO-enhanced MR image set and 0.82 and 0.94 for the DW SENSE image set. During SPIO-enhanced MR image interpretation, lesions 1 cm in diameter or smaller showed significantly lower sensitivity than lesions larger than 1 cm in diameter. During both interpretation sessions, left lobe lesions showed significantly lower sensitivity than right lobe lesions. CONCLUSION: Combined reading of DW SENSE images and T2-weighted fast SE and dual-echo T1-weighted FFE MR images showed higher accuracy in the detection of hepatic metastases than did reading of SPIO-enhanced MR images.     

Neutrophil-derived MMP-9 mediates synergistic mobilization of hematopoietic stem and progenitor cells by the combination of G-CSF and the chemokines GRObeta/CXCL2 and GRObetaT/CXCL2delta4

Mobilized peripheral blood stem cells (PBSCs) are widely used for transplantation, but mechanisms mediating their release from marrow are poorly understood. We previously demonstrated that the chemokines GRObeta/CXCL2 and GRObetaT/CXCL2Delta4 rapidly mobilize PBSC equivalent to granulocyte colony-stimulating factor (G-CSF) and are synergistic with G-CSF. We now show that mobilization by GRObeta/GRObetaT and G-CSF, alone or in combination, requires polymorphonuclear neutrophil (PMN)-derived proteases. Mobilization induced by GRObeta/GRObetaT is associated with elevated levels of plasma and marrow matrix metalloproteinase 9 (MMP-9) and mobilization and MMP-9 are absent in neutrophil-depleted mice. G-CSF mobilization correlates with elevated neutrophil elastase (NE), cathepsin G (CG), and MMP-9 levels within marrow and is partially blocked by either anti-MMP-9 or the NE inhibitor MeOSuc-Ala-Ala-Pro-Val-CMK. Mobilization and protease accumulation are absent in neutrophil-depleted mice. Synergistic PBSC mobilization observed when G-CSF and GRObeta/GRObetaT are combined correlates with a synergistic rise in the level of plasma MMP-9, reduction in marrow NE, CG, and MMP-9 levels, and a coincident increase in peripheral blood PMNs but decrease in marrow PMNs compared to G-CSF. Synergistic mobilization is completely blocked by anti-MMP-9 but not MeOSuc-Ala-Ala-Pro-Val-CMK and absent in MMP-9-deficient or PMN-depleted mice. Our results indicate that PMNs are a common target for G-CSF and GRObeta/GRObetaT-mediated PBSC mobilization and, importantly, that synergistic mobilization by G-CSF plus GRObeta/GRObetaT is mediated by PMN-derived plasma MMP-9.     

Molecular interaction of imino sugars with human α-galactosidase: Insight into the mechanism of complex formation and pharmacological chaperone action in Fabry disease

Enzyme enhancement therapy (EET) for Fabry disease involving imino sugars has been developed and attracted interest. It is thought that imino sugars act as pharmacological chaperones for wild-type and mutant α-galactosidases (GLAs) in cells, but the mechanisms underlying the molecular interactions between the imino sugars and the enzyme have not been clarified yet. We examined various kinds of imino sugars and found that galactostatin bisulfite (GBS) inhibited GLA in vitro and increased the enzyme activity in cultured Fabry fibroblasts as in the case of 1-deoxygalactonojirimycin (DGJ). Then, we analyzed the molecular interactions between the imino sugars and recombinant human GLA by means of isothermal titration calorimetry and surface plasmon resonance biosensor assays, and first determined the thermodynamic and binding-kinetics parameters of imino sugar and GLA complex formation. The results revealed that DGJ bound to the enzyme more strongly than GBS, the binding of DGJ to the enzyme protein being enthalpy-driven. In the case of GBS, the reaction was mainly enthalpy-driven, but there was a possibility that entropy-driven factors were involved in the binding. Structural analysis in silico revealed that both the chemicals fit into the active-site pocket and undergo hydrogen bonding with residues comprising the active-site pocket including the catalytic ones. The side chain of GBS was oriented towards the entrance of the active-site pocket, and thus it could be in contact with residues comprising the wall of the active-site pocket. Thermodynamic, kinetic and structural studies should provide us with a lot of information for improving EET for Fabry disease.