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High Expression (high + expression)
Terms modified by High Expression Selected AbstractsThe expression of cytosolic phospholipase A2 and biosynthesis of leukotriene B4 in acute myeloid leukemia cellsEUROPEAN JOURNAL OF HAEMATOLOGY, Issue 6 2007Gudmundur Runarsson Abstract Leukotrienes (LT) exert stimulatory effects on myelopoiesis, beside their inflammatory and immunomodulating effects. Here, we have studied the expression and activity of the enzymes involved in the synthesis of leukotriene B4 (LTB4) in acute myeloid leukemia (AML) cells (16 clones) and G-CSF mobilized peripheral blood CD34+ cells. CD34+ cells from patients with non-myeloid malignancies expressed cytosolic phospholipase A2 (cPLA2), 5-lipoxygenase activating protein (FLAP), and leukotriene A4 (LTA4) hydrolase but not 5-lipoxygenase (5-LO). The enzyme cPLA2 was abundantly expressed in AML cells and the activity of the enzyme was high in certain AML clones. The expression of 5-LO, FLAP, and LTA4 hydrolase in AML clones was in general lower than in healthy donor polymorphonuclear leukocytes (PMNL). The calcium ionophore A23187-induced release of [14C] arachidonic acid (AA) in AML cells was low, compared with PMNL, and did not correlate with the expression of cPLA2 protein. Biosynthesis of LTB4, upon calcium ionophore A23187 activation, was only observed in five of the investigated AML clones and only three of the most differentiated clones produced similar amounts of LTB4 as PMNL. The capacity of various cell clones to produce LTs could neither be explained by the difference in [1 , 14C] AA release nor 5-LO expression. Taken together, these results indicate that LT synthesis is under development during early myelopoiesis and the capacity to produce LTs is gained upon maturation. High expression of cPLA2 in AML suggests a putative role of this enzyme in the pathophysiology of this disease. [source] Apoptosis resistance in ulcerative colitis: High expression of decoy receptors by lamina propria T cellsEUROPEAN JOURNAL OF IMMUNOLOGY, Issue 8 2006Raja Fayad Abstract Intestinal mucosa is constantly exposed to normal environmental antigens. A significant number of intestinal mucosal T cells are being deleted through apoptosis. In contrast, T cells from inflamed mucosa of ulcerative colitis patients did not undergo apoptosis. In this study, we determined whether the apoptosis of normal mucosal T cells was induced by antigen receptor stimulation and further determined pathways that mediated the apoptosis. Freshly isolated lamina propria T cells were stimulated with CD3 mAb and apoptosis was determined by Annexin,V staining. Normal mucosal T cells underwent apoptosis upon CD3 mAb stimulation whereas the T cells from inflamed mucosa did not. The apoptosis in normal T cells was blocked by TRAIL-R1:Fc and an inhibiting CD95 antibody. Interestingly, decoy receptor (DcR)1, DcR2, and DcR3 that compete with death receptor (DR)4/5 and CD95 were highly expressed by the T cells from inflamed mucosa, but much lower by T cells from normal mucosa. Our data suggest that normal mucosal T cells are constantly deleted in response to environmental antigens mediated through DR4/5 and CD95 pathways and mucosal T cells from ulcerative colitis resist to undergoing apoptosis due to highly expression of DcR1, DcR2, and DcR3. [source] High expression of a sucrose non-fermenting (SNF1)-related protein kinase from Colletotrichum gloeosporoides f. sp. malvae is associated with penetration of Malva pusilla,FEMS MICROBIOLOGY LETTERS, Issue 2 2002Paul H Goodwin Abstract A sucrose non-fermenting (SNF1)-related protein kinase homologue, cgsnf, from Colletotrichum gloeosporoides f. sp. malvae, a hemibiotrophic fungal pathogen of round-leaved mallow (Malva pusilla) was examined. During infection, cgsnf showed a large peak in expression relative to a constitutively expressed fungal actin gene when appressoria had formed during the penetration phase and then showed much lower expression levels during subsequent necrotrophic growth in the host. In pure culture with glucose or glycerol as sole carbon sources, expression levels were similar to that during necrotrophic growth. Expression was consistently higher in glycerol than in glucose cultures, which may reflect a lower cellular energy status in the fungus. These results are consistent with cgsnf having a role in transmitting nutritional signals, which may be involved with host penetration. [source] Comparative expressed sequence hybridization studies of high-hyperdiploid childhood acute lymphoblastic leukemiaGENES, CHROMOSOMES AND CANCER, Issue 3 2004Alicja M. Gruszka-Westwood The functional consequences of a high-hyperdiploid karyotype, found in up to one-third of cases of acute lymphoblastic leukemia (ALL), are unknown. Using the technique of comparative expressed sequence hybridization (CESH), we sought to address the question of whether increased chromosome copies in hyperdiploid ALL lead to increased gene expression. Relative expression of hyperdiploid ALL blasts versus peripheral blood mononuclear cells was analyzed in 18 patients. Common regions of overexpression corresponding to the presence of tri-/tetrasomies included: Xp22.1,22.2, 4q28, 6q14,15, 6q24, 10p13, 14q23,24, 17q21, 18q12, and 21q21, identified in 28,89% of cases. However, increased expression without underlying trisomy occurred at 3p21.3, 7q11.2, 8p21, and 8q24.1 in 39,90% of cases. High expression at 7q11.2, the most consistent change detected, was confirmed by quantitative PCR. Poor correlation between the presence of tri-/tetrasomy and overexpression was observed for chromosomes 14 and 17. Two cases were reanalyzed versus (i) B cells, (ii) transformed B cells, and (iii) CD34+19+ cells (the putative counterpart of the leukemic cell). A reduction in the number of relatively overexpressed regions was observed with CD34+19+ cells. In particular, the peak at 7q11.2 disappeared, suggesting up-regulation of genes from this region in the early ontology of normal B-cell development. In conclusion, we have shown that tri-/tetrasomies in hyperdiploid ALL lead to an increase in the expression of associated sequences. The choice of a biologically relevant reference is crucial for data interpretation. © 2004 Wiley-Liss, Inc. [source] High expression of B-cell receptor inducible gene BIC in all subtypes of Hodgkin lymphomaGENES, CHROMOSOMES AND CANCER, Issue 1 2003Anke van den Berg In a search for genes specifically expressed in Reed,Sternberg (RS) cells of Hodgkin lymphoma (HL), we applied the serial analysis of gene expression (SAGE) technique on the HL-derived cell line DEV. Genes highly expressed in DEV were subjected to an RT-PCR analysis to confirm the SAGE results. For one of the genes, a high expression was observed in DEV and other HL-derived cell lines but not in non-Hodgkin lymphoma (NHL),derived cell lines and normal controls, suggesting an HL-specific expression. This gene corresponds to the human BIC gene, a member of the noncoding mRNA-like molecules. RNA in situ hybridization (ISH) indicated an exclusive nucleolar localization of BIC transcripts in all RS cells in 91% of HL cases, including nodular lymphocyte predominance (NLP) HL and classical HL. Analyses of normal human tissues revealed BIC transcripts in only a small number of CD20-positive B-cells in lymph node and tonsil tissue, albeit at a much lower level compared to that of RS cells. BIC RT-PCR in the Burkitt lymphoma,derived cell line Ramos demonstrated a significant up-regulation upon cross-linking of the B-cell receptor (BcR). I,B,-mediated blocking of NF-,B translocation in Ramos did not effect the up-regulation of BIC expression upon BcR triggering, suggesting that activation of NF-,B is not involved in regulation of BIC expression. In summary, our data show that expression of BIC is specific for RS cells of HL. In normal tissue, BIC is expressed weakly in a minority of germinal center B cells. Expression of BIC can be modified/influenced by BcR triggering, indicating that BIC might play a role in the selection of B cells. © 2003 Wiley-Liss, Inc. [source] Prognostic significance of the therapeutic targets histone deacetylase 1, 2, 6 and acetylated histone H4 in cutaneous T-cell lymphomaHISTOPATHOLOGY, Issue 3 2008L Marquard Aims:, Aberrant histone acetylation has been associated with malignancy and histone deacetylase (HDAC) inhibitors are currently being investigated in numerous clinical trials. So far, the malignancy most sensitive to HDAC inhibitors has been cutaneous T-cell lymphoma (CTCL). The reason for this sensitivity is unclear and studies on HDAC expression and histone acetylation in CTCL are lacking. The aim of this study was to address this issue. Methods and results:, The immunohistochemical expression of HDAC1, HDAC2, HDAC6, and acetylated H4 was examined in 73 CTCLs and the results related to histological subtypes and overall survival. HDAC1 was most abundantly expressed (P < 0.0001), followed by HDAC2; HDAC6 and H4 acetylation were equally expressed. HDAC2 (P = 0.001) and H4 acetylation (P = 0.03) were significantly more common in aggressive than indolent CTCL subtypes. In contrast, no differences were observed for HDAC1 and HDAC6. In a Cox analysis, elevated HDAC6 was the only parameter showing significant influence on survival (P = 0.04). Conclusions:, High expression of HDAC2 and acetylated H4 is more common in aggressive than indolent CTCL. HDAC6 expression is associated with a favorable outcome independent of the subtype. [source] Expression profiling correlates with treatment response in women with advanced serous epithelial ovarian cancerINTERNATIONAL JOURNAL OF CANCER, Issue 4 2006Tanya R. Newton Abstract The majority of epithelial ovarian carcinomas are of serous subtype, with most women presenting at an advanced stage. Approximately 70% respond to initial chemotherapy but eventually relapse. We aimed to find markers of treatment response that might be suitable for routine use, using the gene expression profile of tumor tissue. Thirty one women with histologically-confirmed late-stage serous ovarian cancer were classified into 3 groups based on response to treatment (nonresponders, responders with relapse less than 12 months and responders with no relapse within 12 months). Gene expression profiles of these specimens were analyzed with respect to treatment response and survival (minimum 36 months follow-up). Patients' clinical features did not correlate with prognosis, or with specific gene expression patterns of their tumors. However women who did not respond to treatment could be distinguished from those who responded with no relapse within 12 months based on 34 gene transcripts (p < 0.02). Poor prognosis was associated with high expression of inhibitor of differentiation-2 (ID2) (p = 0.001). High expression of decorin (DCN) and ID2 together was strongly associated with reduced survival (p = 0.003), with an estimated 7-fold increased risk of dying (95% CI 1.9,29.6; 14 months survival) compared with low expression (44 months). Immunohistochemical analysis revealed both nuclear and cytoplasmic distribution of ID2 in ovarian tumors. High percentage of nuclear staining was associated with poor survival, although not statistically significantly. In conclusion, elevated expression of ID2 and DCN was significantly associated with poor prognosis in a homogeneous group of ovarian cancer patients for whom survival could not be predicted from clinical factors. © 2006 Wiley-Liss, Inc. [source] AML1 amplification and 17q25 deletion in a case of childhood acute lymphoblastic leukemiaJOURNAL OF CLINICAL LABORATORY ANALYSIS, Issue 6 2009Tuna Gulten Abstract We report a case of childhood acute lymphoblastic leukemia (ALL) with both acute myeloid leukemia 1 (AML1) amplification and 17q25 deletion. AML1 gene is located on 21q22 and encodes a transcription factor. AML1 amplification is a common finding in childhood ALL, and itis observed as an increase in gene copy number by the FISH analysis. The mechanism of AML1 amplification is not associated with AML1 gene mutations. The 17q25 is a gene-rich chromosomal location and distinct abnormalities of this region have been observed in previous cases of different kinds of leukemia. Deletion of the 17q25 region has been reported in two leukemia patients. Septin 9 (SEPT9) and survivin genes are located on 17q25. High expression of these genes and AML1 amplification are regarded as markers in tumorigenesis and disease progression; however, more data are needed for accurate prognostic evaluation. J. Clin. Lab. Anal. 23:368,371, 2009. © 2009 Wiley-Liss, Inc. [source] Trastuzumab in Primary Inflammatory Breast Cancer (IBC): High Pathological Response Rates and Improved OutcomeTHE BREAST JOURNAL, Issue 5 2010Shaheenah Dawood MRCP (UK) Abstract:, Inflammatory breast cancer (IBC) represents a rare but aggressive and lethal form of locally advanced breast cancer (LABC) and frequently with HER-2 neu overexpressed or amplified. We retrospectively identified 16 newly diagnosed HER-2/neu-positive IBC patients who were treated with preoperative trastuzumab. We determined the pathological complete response rate (pCR) when trastuzumab was added to preoperative chemotherapy in patients with HER2/neu-positive IBC. Furthermore, we assessed the expression of CXCR4 in metastatic recurrence sites. Ten patients (62.5%) achieved a pCR. Six patients (37.5%) achieved a partial response. Median follow-up of all patients was 24.2 months. Four (25%) patients have experienced a progression, of which three were in the brain. Two-year progression-free survival was 59.4% (95% CI 35,100). High expression of CXCR4 was detected in the brain metastases. We conclude that in spite of high pCR rates among women with HER-2/neu-positive IBC treated with neoadjuvant trastuzumab-based regimens the outcome remains dismal and brain recurrences are frequent. CXCR4 may represent a novel therapeutic target. [source] Activation of Signal Transducers and Activators of Transcription 3 and Overexpression of its Target Gene CyclinD1 in Laryngeal Carcinomas,THE LARYNGOSCOPE, Issue 11 2008Bin Liu MD Abstract Objectives/Hypothesis: Constitutive activation of signal transducers and activators of transcription (STAT) 3 has been observed in many solid tumors including head and neck squamous cell carcinoma. Expression and activation of STAT3 in laryngeal carcinoma have not been fully understood. The study aims to investigate the expression and activation of STAT3 in laryngeal carcinoma, the relationship between activated STAT3 and its downstream target gene CyclinD1 and the related clinicopathological factors of activated STAT3. Study Design: Prospective. Methods: Sixty-four samples of laryngeal squamous cell carcinoma and 12 samples of control mucosa obtained from total laryngectomy cases were analyzed using Western blot analysis and reverse transcriptase-polymerase chain reaction. Statistical analysis was performed using SPSS. Results: The overexpression of both STAT3 and CyclinD1 mRNA was observed in all samples of laryngeal squamous cell carcinoma. The mRNA levels of STAT3 and CyclinD1 in carcinoma tissue were 2.1- and 2.3-fold higher than those in control mucosa, respectively; the differences were statistically significant (P < .01). The overexpression of STAT3, p-STAT3, and CyclinD1 protein was also observed in all tumor samples. The protein levels of STAT3, p-STAT3, and CyclinD1 in carcinoma tissue were 1.6-, 4.5-, and 2.0-fold higher than those in control mucosa respectively; the differences were statistically significant (P < .01). There was a positive correlation between p-STAT3 protein and CyclinD1 mRNA (Pearson correlation coefficient = 0.827, P < .01). There were significant correlations between the overexpression of p-STAT3 protein and clinical T stage (P < .01), and tumor size (P < .05). The p-STAT3 protein level of patients in T1, T2 was higher than that of patients in T3, T4. The p-STAT3 protein level of patients with tumor size within 20 mm was higher than that of patients with tumor size more than 20 mm. Conclusions: High expression and activation of STAT3 exist in laryngeal carcinomas. Activated STAT3 may take effect on promoting transcription of its downstream target gene CyclinD1. The role of activation of STAT3 in laryngeal carcinogenesis needs further research. [source] Galectin 3 induces a distinctive pattern of cytokine and chemokine production in rheumatoid synovial fibroblasts via selective signaling pathwaysARTHRITIS & RHEUMATISM, Issue 6 2009Andrew Filer Objective High expression of galectin 3 at sites of joint destruction in rheumatoid arthritis (RA) suggests that galectin 3 plays a role in RA pathogenesis. Previous studies have demonstrated the effects of galectins on immune cells, such as lymphocytes and macrophages. This study was undertaken to investigate the hypothesis that galectin 3 induces proinflammatory effects in RA by modulating the pattern of cytokine and chemokine production in synovial fibroblasts. Methods Matched samples of RA synovial and skin fibroblasts were pretreated with galectin 3 or tumor necrosis factor , (TNF,), and the levels of a panel of cytokines, chemokines, and matrix metalloproteinases (MMPs) were determined using enzyme-linked immunosorbent assays and multiplex assays. Specific inhibitors were used to dissect signaling pathways, which were confirmed by Western blotting and NF-,B activation assay. Results Galectin 3 induced secretion of interleukin-6 (IL-6), granulocyte,macrophage colony-stimulating factor, CXCL8, and MMP-3 in both synovial and skin fibroblasts. By contrast, galectin 3,induced secretion of TNF,, CCL2, CCL3, and CCL5 was significantly greater in synovial fibroblasts than in skin fibroblasts. TNF, blockade ruled out autocrine TNF,-stimulated induction of chemokines. The MAPKs p38, JNK, and ERK were necessary for IL-6 production, but phosphatidylinositol 3-kinase (PI 3-kinase) was required for selective CCL5 induction. NF-,B activation was required for production of both IL-6 and CCL5. Conclusion Our findings indicate that galectin 3 promotes proinflammatory cytokine secretion by tissue fibroblasts. However, galectin 3 induces the production of mononuclear cell,recruiting chemokines uniquely from synovial fibroblasts, but not matched skin fibroblasts, via a PI 3-kinase signaling pathway. These data provide further evidence of the role of synovial fibroblasts in regulating the pattern and persistence of the inflammatory infiltrate in RA and suggest a new and important functional consequence of the observed high expression of galectin 3 in the rheumatoid synovium. [source] Stromal cell,derived factor 1/CXCR4 signaling is critical for the recruitment of mesenchymal stem cells to the fracture site during skeletal repair in a mouse modelARTHRITIS & RHEUMATISM, Issue 3 2009Toshiyuki Kitaori Objective Stromal cell,derived factor 1 (SDF-1; CXCL12/pre,B cell growth-stimulating factor) is a dominant chemokine in bone marrow and is known to be involved in inflammatory diseases, including rheumatoid arthritis. However, its role in bone repair remains unknown. The purpose of this study was to investigate the role of SDF-1 and its receptor, CXCR4, in bone healing. Methods The expression of SDF-1 during the repair of a murine structural femoral bone graft was examined by real-time polymerase chain reaction and immunohistochemical analysis. The bone graft model was treated with anti,SDF-1 neutralizing antibody or TF14016, an antagonist for CXCR4, and evaluated by histomorphometry. The functional effect of SDF-1 on primary mesenchymal stem cells was determined by in vitro and in vivo migration assays. New bone formation in an exchanging-graft model was compared with that in the autograft models, using mice partially lacking SDF-1 (SDF-1+/,) or CXCR4 (CXCR4+/,). Results The expression of SDF1 messenger RNA was increased during the healing of live bone grafts but was not increased in dead grafts. High expression of SDF-1 protein was observed in the periosteum of the live graft. New bone formation was inhibited by the administration of anti,SDF-1 antibody or TF14016. SDF-1 increased mesenchymal stem cell chemotaxis in vitro in a dose-dependent manner. The in vivo migration study demonstrated that mesenchymal stem cells recruited by SDF-1 participate in endochondral bone repair. Bone formation was decreased in SDF-1+/, and CXCR4+/, mice and was restored by the graft bones from CXCR4+/, mice transplanted into the SDF-1+/, femur, but not vice versa. Conclusion SDF-1 is induced in the periosteum of injured bone and promotes endochondral bone repair by recruiting mesenchymal stem cells to the site of injury. [source] High expression of connective tissue growth factor in pre-B acute lymphoblastic leukaemiaBRITISH JOURNAL OF HAEMATOLOGY, Issue 6 2007Joanne M. Boag Summary In recent years microarrays have been used extensively to characterize gene expression in acute lymphoblastic leukaemia (ALL). Few studies, however, have analysed normal haematopoietic cell populations to identify altered gene expression in ALL. We used oligonucleotide microarrays to compare the gene expression profile of paediatric precursor-B (pre-B) ALL specimens with two control cell populations, normal CD34+ and CD19+IgM, cells, to focus on genes linked to leukemogenesis. A set of eight genes was identified with a ninefold higher average expression in ALL specimens compared with control cells. All of these genes were significantly deregulated in an independent cohort of 101 ALL specimens. One gene, connective tissue growth factor (CTGF, also known as CCN2), had exceptionally high expression, which was confirmed in three independent leukaemia studies. Further analysis of CTGF expression in ALL revealed exclusive expression in B-lineage, not T-lineage, ALL. Within B-lineage ALL approximately 75% of specimens were consistently positive for CTGF expression, however, specimens containing the E2A-PBX1 translocation showed low or no expression. Protein studies using Western blot analysis demonstrated the presence of CTGF in ALL cell-conditioned media. These findings indicate that CTGF is secreted by pre-B ALL cells and may play a role in the pathophysiology of this disease. [source] High expression of BUBR1 is one of the factors for inducing DNA aneuploidy and progression in gastric cancerCANCER SCIENCE, Issue 3 2010Koji Ando (Cancer Sci 2010; 101: 639,645) Gastric cancers show high frequency of DNA aneuploidy, a phenotype of chromosomal instability. It is suggested that the abnormal spindle assembly checkpoint is involved in DNA aneuploidy, but the underlying mechanism is still unclear. We studied the mechanism by assessing the expression of BUBR1 in gastric cancer. The DNA ploidy patterns of 116 gastric cancer samples obtained from the Department of Surgery and Science at Kyushu University Hospital were analyzed. Of those, DNA aneuploidy was seen in 70 (60.3%) cases of gastric cancer. The expression of BUBR1 was studied by immunohistochemistry in 181 gastric cancer samples and by real-time RT-PCR in several gastric cancer cell lines. Ninety-one (50.3%) cases had high expression of BUBR1 and those cases correlated significantly with DNA aneuploidy (P < 0.05). Also high expression of BUBR1 cases had significant correlation with deep invasion, lymph node metastasis, liver metastasis, and poor prognosis. In gastric cancer cell lines, high expression of BUBR1 had a significant relationship with DNA aneuploidy (P < 0.05). Then, gastric cancer cell lines MKN-28 and SNU-1 were transfected with full-length BUBR1 to observe the significance of the change in BUBR1 expression. Enforced expression of BUBR1 resulted in changes to the ploidy pattern and high Ki-67 expression. Collectively, our clinical and in vitro data indicate that high expression of BUBR1 may be one of causative factors for the induction of DNA aneuploidy and progression of gastric cancer. [source] Correlation of angiogenesis with 18F-FMT and 18F-FDG uptake in non-small cell lung cancerCANCER SCIENCE, Issue 4 2009Kyoichi Kaira L-[3- 18F]-,-methyltyrosine (18F-FMT) is an amino-acid tracer for positron-emission tomography (PET). We have conducted a clinicopathologic study to elucidate the correlation of angiogenesis with 18F-FMT and 2-[18F]-fluoro-2-deoxy-D-glucose (18F-FDG) uptake in patients with non-small cell lung cancer (NSCLC). Thirty-seven NSCLC patients were enrolled in this study, and two PET studies with 18F-FMT and 18F-FDG were performed. Uptake of PET tracers was evaluated with standardized uptake value. Vascular endothelial growth factor (VEGF), CD31, CD34, L-type amino acid transporter 1 (LAT1) and Ki-67 labeling index of the resected tumors were analyzed by immunohistochemical staining, and correlated with the clinicopathologic variables and the uptake of PET tracers. The median VEGF rate was 45% (range, 10,78%). High expression was seen in 30 patients (81%, 30/37). VEGF expression was statistically associated with progressively growing microvessel count. VEGF showed a correlation with LAT1 expression (P = 0.04) and Ki-67 labeling index (P = 0.01). However, it showed no correlation with age, gender, disease stage, tumor size, and histology. Microvessel density (MVD) showed no correlation with any parameters. 18F-FMT and 18F-FDG uptake correlated significantly with VEGF (P < 0.0001, P = 0.026, respectively), whereas the correlation of 18F-FMT and VEGF was more meaningful. The present study demonstrated that the metabolic activity of primary tumors as evaluated by PET study with 18F-FMT and 18F-FDG is related to tumor angiogenesis and the proliferative activity in NSCLC. (Cancer Sci 2009; 100: 753,758) [source] The effect of ZD1839 (IressaTM), an epidermal growth factor receptor tyrosine kinase inhibitor, in combination with cisplatin, on apoptosis in SCC-15 cellsCELL PROLIFERATION, Issue 2 2005A. Al-Hazzaa High expression of the epidermal growth factor receptor has been implicated in the development of squamous cell carcinomas of head and neck. ZD1839 (,Iressa') is an orally active, selective epidermal growth factor receptor tyrosine kinase inhibitor that blocks signal transduction pathways implicated in proliferation and survival of cancer cells, and other host-dependent processes promoting cancer growth. Here, growth arrest was observed with 3.64 µm ZD1839. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (sMTT) viability assay revealed a significant decrease (P < 0.001) in the percentage of surviving cells upon treatment with ZD1839 and cisplatin compared with cisplatin or ZD1839 on their own. Combined therapy of 3.64 µm ZD1839 for 24 h, prior to administration of 100 µm cisplatin, significantly (P < 0.001) and additively increased the cytotoxicity effect of cisplatin. p53-independent apoptosis was seen with cisplatin treatment, a novel finding. These data support the use of ZD1839 in anti-cancer therapy, and particularly in combination therapy. Cisplatin may induce p53-independent apoptosis. Over-expression of Bcl-2 in head and neck squamous cell carcinoma tumour cell lines is unlikely to be a general mechanism to protect these cells from apoptosis. [source] Close association of CD8+/CD38bright with HIV-1 replication and complex relationship with CD4+ T-cell count,CYTOMETRY, Issue 4 2009Edouard Tuaillon Abstract Background: Measuring lymphocyte activation provides information in addition to CD4+ T-cell count for immune monitoring of HIV-1 infected patients. CD38 is a well-established activation marker that is generally analyzed on the whole population of CD8+ T-cells. Focusing specifically on CD38 high expression (CD8+/CD38bright) may be an interesting surrogate gating strategy because CD38bright characterizes principally activated memory cells. Methods: CD8+/CD38bright was investigated in 1,353 HIV-1 infected patients over a one-year period to establish relevant cutoff values and clarify the relationships of this marker with HIV-1 RNA viral load (VL) and CD4+ T-cell count. Results: The CD8+/CD38bright (>8,500 CD38 binding site per cells) is well correlated with HIV-1 VL (r = 0.87, P < 0.001) in this longitudinal follow-up of nonimmunodepressed patients that initiated antiviral therapy (ART). In aviremic patients on ART, the marker was highly predictive of VL rebound (sensitivity 93%, specificity 64% for a VL level of detection >200 copies/ml). While the CD8+/CD38bright moderately correlated with CD4+ T-cell count independently of the VL (r = ,0.37, P < 0.001), it increased dramatically in aviremic patient groups that exhibited profound CD4+ T-cell depletion (median 39% for CD4+ T-cell counts <50/mm3). This result indicates that other additional immunological and/or viral factors than readily detectable HIV-1 replication appears to be involved in T-cell activation of immunodepressed individuals. Conclusions: CD8+/CD38bright is an effective marker for monitoring T-cell activation, which is a central factor of HIV-1 pathogenesis. This gating strategy requires only a single additional staining in conventional four color CD4 protocols. © 2008 Clinical Cytometry Society [source] Reduced calcium tolerance in rat cardiomyocytes after myocardial infarctionACTA PHYSIOLOGICA, Issue 4 2002I. Sjaastad ABSTRACT During ischaemia and reperfusion the intracellular Na+ concentration is elevated in the cardiomyocytes and the cells are depolarized, both favouring reverse mode Na,Ca-exchange loading of the cell with Ca2+. We examined whether cardiomyocytes from rats with congestive heart failure (CHF) and younger rats (HINCX) which both have a high expression of the Na,Ca-exchanger protein (NCX) showed reduced tolerance to extracellular Ca2+. The CHF was induced in Isofluran anaesthetized rats by left coronary artery ligation. Isolated cardiomyocytes were loaded with Fura-2AM and 140 mm Na+ and exposed to 0.05 mm Ca2+. Expression of the Na,Ca-exchanger protein was analysed. Fura-2 340/380 ratio rose more rapidly in HINCX and CHF than in SHAM, and the rise was abolished by Ni2+. Hypercontracture developed more frequently in HINCX and CHF than in SHAM cells. The amount of NCX was 54% higher in HINCX and 76% higher in CHF compared with SHAM. Na+ -loaded cardiomyocytes from CHF and HINCX rats are more susceptible to Ca2+ overload than SHAM cells because of the increased capacity for Na,Ca-exchange. [source] Tumoral and tissue-specific expression of the major human ,-tubulin isotypes,CYTOSKELETON, Issue 4 2010Luis J. Leandro-García Abstract The ,-tubulins are microtubule components encoded by a multigene family, which produces slightly different proteins with complex expression patterns. Several widely used anticancer drugs base their activity on ,-tubulin binding, microtubule dynamics alteration, and cell division blockage. The expression of these drug targets in tumoral and normal cells could be of crucial importance for therapy outcome, unfortunately, the complex ,-tubulin expression patterns have been poorly characterized in human. In this study, we developed a quantitative RT-PCR technique that accurately determines the mRNA expression of the eight human ,-tubulin isotypes, encoding class I, IIa, IIb, III, IVa, IVb, V, and VI and applied it to 21 nontumoral tissues and 79 tumor samples belonging to seven cancer types. In the nontumoral tissues, we found that, overall, TUBB (I), TUBB2C (IVb), and TUBB6 (V) were ubiquitous, TUBB1(VI) was hematopoietic cell-specific, and TUBB2A (IIa), TUBB2B (IIb), TUBB3 (III), and TUBB4 (IVa) had high expression in brain; however, the contribution of the different isotypes to the total ,-tubulin content varied for each tissue and had a complex pattern. In tumoral tissues, most isotypes exhibited an altered expression in specific tumor types or related to tumoral characteristics. In general, TUBB3 showed a great increase in expression while TUBB6 expression was largely decreased in most tumors. Thus, normal tissues showed a complex ,-tubulin isotype distribution, which could contribute to the toxicity profile of the microtubule-binding drugs. In addition, the specific isotypes significantly altered in tumors might represent markers for drug response. © 2010 Wiley-Liss, Inc. [source] Sexual dimorphism of g-protein subunit Gng13 expression in the cortical region of the developing mouse ovaryDEVELOPMENTAL DYNAMICS, Issue 7 2007Akihiro Fujino Abstract In our search for genes required for the development and function of mouse gonads, we identified Gng13 (guanine nucleotide binding protein 13, gamma), a gene with an embryonic expression pattern highly restricted to the ovary. Based on reverse transcriptase-polymerase chain reaction (RT-PCR) and whole-mount in situ hybridization, Gng13 is expressed in both XX and XY gonads at embryonic day (E) 11.5, but becomes up-regulated in the XX gonad by E12.5. Expression is retained after treatment with busulfan, a chemical known to eliminate germ cells, pointing to the soma as a site of Gng13 transcription. In situ hybridization of embryonic ovarian tissue sections further localized the expression to the cortex of the developing XX gonad. Gng13 expression in the adult is also highly restricted. Northern blot analyses and Genomic Institute of the Novartis Research Foundation expression profiling of adult tissues detected very high expression in the cerebrum and cerebellum, in addition to, a weaker signal in the ovary. Gng13 belongs to a well-known family of signal transduction molecules with functions in many aspects of development and organ physiology. Here, we report that, in the developing mouse embryo, expression of Gng13 mRNA is highly restricted to the cortex of the XX gonad during sexual differentiation, suggesting a role for this gene during ovarian development. Developmental Dynamics 236:1991,1996, 2007. © 2007 Wiley-Liss, Inc. [source] Conservation and expression of IQ-domain-containing calpacitin gene products (neuromodulin/GAP-43, neurogranin/RC3) in the adult and developing oscine song control systemDEVELOPMENTAL NEUROBIOLOGY, Issue 2-3 2009David F. Clayton Abstract Songbirds are appreciated for the insights they provide into regulated neural plasticity. Here, we describe the comparative analysis and brain expression of two gene sequences encoding probable regulators of synaptic plasticity in songbirds: neuromodulin (GAP-43) and neurogranin (RC3). Both are members of the calpacitin family and share a distinctive conserved core domain that mediates interactions between calcium, calmodulin, and protein kinase C signaling pathways. Comparative sequence analysis is consistent with known phylogenetic relationships, with songbirds most closely related to chicken and progressively more distant from mammals and fish. The C-terminus of neurogranin is different in birds and mammals, and antibodies to the protein reveal high expression in adult zebra finches in cerebellar Purkinje cells, which has not been observed in other species. RNAs for both proteins are generally abundant in the telencephalon yet markedly reduced in certain nuclei of the song control system in adult canaries and zebra finches: neuromodulin RNA is very low in RA and HVC (relative to the surrounding pallial areas), whereas neurogranin RNA is conspicuously low in Area X (relative to surrounding striatum). In both cases, this selective downregulation develops in the zebra finch during the juvenile song learning period, 25,45 days after hatching. These results suggest molecular parallels to the robust stability of the adult avian song control circuit. © 2008 Wiley Periodicals, Inc. Develop Neurobiol, 2009 [source] A possible role for dihydrodiol dehydrogenase in the formation of benzo[a]pyrene-DNA adducts in lung cancer cells and tumor tissuesENVIRONMENTAL AND MOLECULAR MUTAGENESIS, Issue 1 2007Ya-Wen Cheng Abstract Epidemiological studies indicate that there is a gender difference in the susceptibility to tobacco and environmental carcinogens, and this gender difference is suspected to result in a higher risk for lung cancer among women. However, the molecular mechanisms underlying this sexual dimorphism remain unclear. In the present study, we have evaluated the roles of CYP1A1 and dihydrodiol dehydrogenase (DDH) in the formation of benzo[a]pyrene (BaP) DNA adducts in various lung cancer cell lines. Among six lung cancer cell lines tested, higher adduct levels were observed in CL-3 and CL1-1 cells, which had relatively high expression of both CYP1A1 and DDH isoform 1 (DHH1). To determine whether a reduction in DDH expression changed the adduct levels, an siRNA was used to knock down DDH1 expression in CL-3 cells. The BaP adduct levels in siDDH-CL-3 cells increased 1.4,2.2-fold relative to that of the parental CL-3 cells. We also examined BaP-like DNA adducts, and CYP1A1 and DDH1 expression by immunohistochemistry in 120 lung tumors. Detection of DNA adducts correlated with CYP1A1-positive tumors (P = 0.023), but not with DDH1-positive tumors. In addition, 28 of 33 tumors (85%) that were CYP1A1-positive and DDH1-negative contained detectable levels of DNA adducts, a proportion that was higher than for tumors from the other three categories of CYP1A1 and DDH1 expression (P = 0.012). Finally, a greater proportion of adduct-positive tumors from females were CYP1A1-positive/DDH1-negative (45.3%) than were tumors from males (27.3%). These results suggest that the reduction of DDH expression in lung tumors may contribute to an increase in DNA adduct levels, which may be partly responsible for the higher susceptibility of female lung cancer patients to DNA damage. Environ. Mol. Mutagen., 2007. © 2006 Wiley-Liss, Inc. [source] Mesothelin, a possible target for immunotherapy, is expressed in primary AML cellsEUROPEAN JOURNAL OF HAEMATOLOGY, Issue 4 2007Daniel Steinbach Abstract Background:, Mesothelin is a promising candidate for tumor-specific therapy because of its limited expression in normal tissues and high expression in several cancers. The expression of the protein mesothelin in hematological malignancies has not yet been analyzed. SS1(dsFv)PE38 is a recombinant anti-mesothelin immunotoxin which is undergoing clinical evaluation in patients with mesothelin-expressing tumors. Methods and Results:, In this study we show that the mesothelin protein is expressed in leukemic cells from children with acute myeloid leukemia (AML). This finding was confirmed by western blot, immunocytochemistry and real time polymerase chain reaction (PCR). Despite the expression of mesothelin, the patient samples were not sensitive to immunotoxin SS1(dsFv)PE38 in MTT assays. Conclusions:, Primary AML cells express mesothelin but SS1(dsFv)PE38 is not active in killing these cells. Other approaches that utilize mesothelin as a target might be more effective and should be tested against AML cells. [source] Intestinal double-positive CD4+CD8+ T,cells are highly activated memory cells with an increased capacity to produce cytokinesEUROPEAN JOURNAL OF IMMUNOLOGY, Issue 3 2006Bapi Pahar Dr. Abstract Peripheral blood and intestinal CD4+CD8+ double-positive (DP) T,cells have been described in several species including humans, but their function and immunophenotypic characteristics are still not clearly understood. Here we demonstrate that DP T,cells are abundant in the intestinal lamina propria of normal rhesus macaques (Macaca mulatta). Moreover, DP T,cells have a memory phenotype and are capable of producing different and/or higher levels of cytokines and chemokines in response to mitogen stimulation compared to CD4+ single-positive T,cells. Intestinal DP T,cells are also highly activated and have higher expression of CCR5, which makes them preferred targets for simian immunodeficiency virus/HIV infection. Increased levels of CD69, CD25 and HLA-DR, and lower CD62L expression were found on intestinal DP T,cells populations compared to CD4+ single-positive T,cells. Collectively, these findings demonstrate that intestinal and peripheral blood DP T,cells are effector cells and may be important in regulating immune responses, which distinguishes them from the immature DP cells found in the thymus. Finally, these intestinal DP T,cells may be important target cells for HIV infection and replication due to their activation, memory phenotype and high expression of CCR5. [source] Oligodendroglial tau filament formation in transgenic mice expressing G272V tauEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 11 2001Jürgen Götz Abstract Genetic evidence indicates that several mutations in tau, including G272V, are linked to frontotemporal dementia with parkinsonism. We expressed this mutation in mouse brains by combining a prion protein promoter-driven expression system with an autoregulatory transactivator loop that resulted in high expression of human G272V tau in neurons and in oligodendrocytes. We show that G272V tau can form filaments in murine oligodendrocytes. Electron microscopy established that the filaments were either straight or had a twisted structure; these were 17,20 nm wide and had a periodicity of ,,75 nm. Filament formation was associated with tau phosphorylation at distinct sites, including the AT8 epitope 202/205 in vivo. Immunogold electron microscopy of sarcosyl-extracted spinal cords from G272V transgenic mice using phosphorylation-dependent antibodies AT8 or AT100 identified several sparsely gold-labelled 6-nm filaments. In the spinal cord, fibrillary inclusions were also identified by thioflavin-S fluorescent microscopy in oligodendrocytes and motor neurons. These results establish that expression of the G272V mutation in mice causes oligodendroglial fibrillary lesions that are similar to those seen in human tauopathies. [source] Lipopolysaccharide alters decorin and biglycan synthesis in rat alveolar bone osteoblasts: consequences for bone repair during periodontal diseaseEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 3 2008Helen C. Roberts A prime pathogenic agent associated with periodontitis is lipopolysaccharide (LPS) derived from Porphyromonas gingivalis. This study investigated the effects of P. gingivalis LPS on osteoblasts, which are responsible for alveolar bone repair. Bone cells were obtained from explants of rat alveolar bone chips and cultured with 0,200 ng ml,1 of P. gingivalis LPS. Porphyromonas gingivalis LPS significantly increased cell proliferation and inhibited osteoblast differentiation, as judged by reduced alkaline phosphatase activity. Analysis of biglycan mRNA and protein levels indicated that P. gingivalis LPS significantly delayed the normally high expression of biglycan during the early stages of culture, which are associated with cell proliferation and early differentiation of progenitor cells. In the presence of P. gingivalis LPS, decorin expression by the alveolar bone cells was reduced during periods of culture relating to collagen fibrillogenesis and mineral deposition. Analysis of glycosaminoglycan chains conjugated to these proteoglycans suggested that in the presence of P. gingivalis LPS, dermatan sulfate persisted within the matrix. This study suggests that P. gingivalis LPS influences the expression and processing of decorin and biglycan in the matrix, altering alveolar bone cell activity and osteoblast phenotype development. The consequences of this altered expression in relation to hindering bone repair as part of the cycle of events during periodontal disease are discussed. [source] Cloning and expression of murine enzymes involved in the salvage pathway of GDP- l -fucoseFEBS JOURNAL, Issue 1 2004GDP- l -fucose pyrophosphorylase, l -fucokinase In the salvage pathway of GDP- l -fucose, free cytosolic fucose is phosphorylated by l -fucokinase to form l -fucose-1-phosphate, which is then further converted to GDP- l -fucose in the reaction catalyzed by GDP- l -fucose pyrophosphorylase. We report here the cloning and expression of murine l -fucokinase and GDP- l -fucose pyrophosphorylase. Murine l -fucokinase is expressed as two transcripts of 3057 and 3270 base pairs, encoding proteins of 1019 and 1090 amino acids with predicted molecular masses of 111 kDa and 120 kDa respectively. Only the longer splice variant of l -fucokinase was enzymatically active when expressed in COS-7 cells. Murine GDP- l -fucose pyrophosphorylase has an open reading frame of 1773 base pairs encoding a protein of 591 amino acids with a predicted molecular mass of 65.5 kDa. GDP- l -fucose, the reaction product of GDP- l -pyrophosphorylase, was identified by HPLC and MALDI-TOF MS analysis. The tissue distribution of murine l -fucokinase and GDP- l -fucose pyrophosphorylase was investigated by quantitative real time PCR, which revealed high expression of l -fucokinase and GDP- l -fucose pyrophosphorylase in various tissues. The wide expression of both enzymes can also be observed from the large amount of data collected from a number of expressed sequence tag libraries, which indicate that not only the de novo pathway alone, but also the salvage pathway, could have a significant role in the synthesis of GDP- l -fucose in the cytosol. [source] Listeria monocytogenes: epidemiology, human disease, and mechanisms of brain invasionFEMS IMMUNOLOGY & MEDICAL MICROBIOLOGY, Issue 2 2008Douglas A. Drevets Abstract Listeria monocytogenes is a facultative intracellular bacterium that has predilection for causing central nervous systemic infections in humans and domesticated animals. This pathogen can be found worldwide in the food supply and most L. monocytogenes infections are acquired through ingestion of contaminated food. The main clinical syndromes caused by L. monocytogenes include febrile gastroenteritis, perinatal infection, and systemic infections marked by central nervous system infections with or without bacteremia. Experimental infection of mice has been used for over 50 years as a model system to study the pathogenesis of this organism including the mechanisms by which it invades the brain. Data from this model indicate that a specific subset of monocytes, distinguished in part by high expression of the Ly-6C antigen, become parasitized in the bone marrow and have a key role in transporting intracellular bacteria across the blood-brain barriers and into the central nervous system. This Minireview will summarize recent epidemiologic and clinical information regarding L. monocytogenes as a human pathogen and will discuss current in vitro and in vivo data relevant to the role of parasitized monocytes and the pathogenetic mechanisms that underlie its formidable ability to invade the central nervous system. [source] Recurrent copy number gain of transcription factor SOX2 and corresponding high protein expression in oral squamous cell carcinomaGENES, CHROMOSOMES AND CANCER, Issue 1 2010Kolja Freier Gene copy number aberrations are involved in oral squamous cell carcinoma (OSCC) development. To delineate candidate genes inside critical chromosomal regions, array-CGH was applied to 40 OSCC specimens using a microarray covering the whole human genome with an average resolution of 1 Mb. Gene copy number gains were predominantly found at 1q23 (9 cases), 3q26 (11), 5p15 (13), 7p11 (7), 8q24 (17), 11q13 (15), 14q32 (8), 19p13 (8), 19q12 (7), 19q13 (8), and 20q13 (9), whereas gene copy number losses were detected at 3p21-3p12 (15), 8p32 (11), 10p12 (8), and 18q21-q23 (10). Subsequent mRNA expression analyses by quantitative real time polymerase chain reaction found high mRNA expression of candidate genes SOX2 in 3q26.33, FSLT3 in 19p13.3, and CCNE1 in 19q12. Tissue microarray (TMA) analyses in a representative OSCC collection found gene copy number gain for SOX2 in 52% (115/223) and for CCNE1 in 31% (72/233) of the tumors. Immunohistochemical analyses on TMA sections of the corresponding proteins detected high expression of SOX2 in 18.1% (49/271) and of CyclinE1 in 23.3% (64/275) of tumors analyzed. These findings indicate that SOX2 and CCNE1 might be activated via gene copy number gain and participate in oral carcinogenesis. The combination of array-CGH with TMA analyses allows rapid pinpointing of novel promising candidate genes, which might be used as therapeutic stratification markers or target molecules for therapeutic interference. © 2009 Wiley-Liss, Inc. [source] High expression of B-cell receptor inducible gene BIC in all subtypes of Hodgkin lymphomaGENES, CHROMOSOMES AND CANCER, Issue 1 2003Anke van den Berg In a search for genes specifically expressed in Reed,Sternberg (RS) cells of Hodgkin lymphoma (HL), we applied the serial analysis of gene expression (SAGE) technique on the HL-derived cell line DEV. Genes highly expressed in DEV were subjected to an RT-PCR analysis to confirm the SAGE results. For one of the genes, a high expression was observed in DEV and other HL-derived cell lines but not in non-Hodgkin lymphoma (NHL),derived cell lines and normal controls, suggesting an HL-specific expression. This gene corresponds to the human BIC gene, a member of the noncoding mRNA-like molecules. RNA in situ hybridization (ISH) indicated an exclusive nucleolar localization of BIC transcripts in all RS cells in 91% of HL cases, including nodular lymphocyte predominance (NLP) HL and classical HL. Analyses of normal human tissues revealed BIC transcripts in only a small number of CD20-positive B-cells in lymph node and tonsil tissue, albeit at a much lower level compared to that of RS cells. BIC RT-PCR in the Burkitt lymphoma,derived cell line Ramos demonstrated a significant up-regulation upon cross-linking of the B-cell receptor (BcR). I,B,-mediated blocking of NF-,B translocation in Ramos did not effect the up-regulation of BIC expression upon BcR triggering, suggesting that activation of NF-,B is not involved in regulation of BIC expression. In summary, our data show that expression of BIC is specific for RS cells of HL. In normal tissue, BIC is expressed weakly in a minority of germinal center B cells. Expression of BIC can be modified/influenced by BcR triggering, indicating that BIC might play a role in the selection of B cells. © 2003 Wiley-Liss, Inc. [source] | ||||||||||||||||||||||||||||||||||||||||