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Gene Array Analysis (gene + array_analysis)
Selected AbstractsCell cycle effects resulting from inhibition of hepatocyte growth factor and its receptor c-Met in regenerating rat livers by RNA interference,HEPATOLOGY, Issue 6 2007Shirish Paranjpe Hepatocyte growth factor (HGF) and its receptor c-Met are involved in liver regeneration. The role of HGF and c-Met in liver regeneration in rat following two-thirds partial hepatectomy (PHx) was investigated using RNA interference to silence HGF and c-Met in separate experiments. A mixture of 2 c-Met-specific short hairpin RNA (ShRNA) sequences, ShM1 and ShM2, and 3 HGF-specific ShRNA, ShH1, ShH3, and ShH4, were complexed with linear polyethylenimine. Rats were injected with the ShRNA/PEI complex 24 hours before and at the time of PHx. A mismatch and a scrambled ShRNA served as negative controls. ShRNA treatment resulted in suppression of c-Met and HGF mRNA and protein compared with that in controls. The regenerative response was assessed by PCNA, mitotic index, and BrdU labeling. Treatment with the ShHGF mixture resulted in moderate suppression of hepatocyte proliferation. Immunohistochemical analysis revealed severe suppression of incorporation of BrdU and complete absence of mitosis in rats treated with ShMet 24 hours after PHx compared with that in controls. Gene array analyses indicated abnormal expression patterns in many cell-cycle- and apoptosis-related genes. The active form of caspase 3 was seen to increase in ShMet-treated rats. The TUNEL assay indicated a slight increase in apoptosis in ShMet-treated rats compared with that in controls. Conclusion: The data indicated that in vivo silencing of c-Met and HGF mRNA by RNA interference in normal rats results in suppression of mRNA and protein, which had a measurable effect on proliferation kinetics associated with liver regeneration. (HEPATOLOGY 2007.) [source] Neutralization of the chemokine CXCL10 reduces apoptosis and increases axon sprouting after spinal cord injuryJOURNAL OF NEUROSCIENCE RESEARCH, Issue 4 2006Janette Glaser Abstract Spinal cord injury (SCI) is followed by a secondary degenerative process that includes cell death. We have previously demonstrated that the chemokine CXCL10 is up-regulated following SCI and plays a critical role in T-lymphocyte recruitment to sites of injury and inhibition of angiogenesis; antibody-mediated functional blockade of CXCL10 reduced inflammation while enhancing angiogenesis. We hypothesized, based on these findings, that the injury environment established by anti-CXCL10 antibody treatment would support greater survival of neurons and enhance axon sprouting compared with the untreated, injured spinal cord. Here, we document gene array and histopathological data to support our hypothesis. Gene array analysis of treated and untreated tissue from spinal cord-injured animals revealed eight apoptosis-related genes with significant expression changes at 3 days postinjury. In support of these data, quantification of TUNEL-positive cells at 3 days postinjury indicated a 75% reduction in the number of dying cells in treated animals compared with untreated animals. Gene array analysis of treated and untreated tissue also revealed six central nervous system growth-related genes with significant expression changes in the brainstem at 14 days postinjury. In support of these data, quantification of anterograde-labeled corticospinal tract fibers indicated a 60,70% increase in axon sprouting caudal to the injury site in treated animals compared with untreated animals. These findings indicate that anti-CXCL10 antibody treatment provides an environment that reduces apoptosis and increases axon sprouting following injury to the adult spinal cord. © 2006 Wiley-Liss, Inc. [source] The interferon-inducible gene IFI16 secretome of endothelial cells drives the early steps of the inflammatory responseEUROPEAN JOURNAL OF IMMUNOLOGY, Issue 8 2010Rossella Baggetta Abstract The IFN-inducible human IFI16 gene is highly expressed in endothelial cells as well as epithelial and hematopoietic tissues. Previous gene array analysis of human umbilical vein endothelial cells overexpressing IFI16 has revealed an increased expression of genes involved in inflammation and apoptosis. In this study, protein array analysis of the IFI16 secretome showed an increased production of chemokines, cytokines and adhesion molecules responsible for leukocyte chemotaxis. Functional analysis of the promoter for CCL20, the chemokine responsible for leukocyte recruitment in the early steps of inflammation, by site-specific mutation demonstrated that NF-,B is the main mediator of CCL20 induction at the transcriptional level. Finally, both Langerhans DC and B-lymphocyte migration triggered by supernatants from IFI16-overexpressing endothelial cells was partially inhibited by Ab inactivating CCL4, CCL5 and CCL20 chemokines. Altogether, these results demonstrate that the IFI16 gene, through its secretome, regulates proinflammatory activity of endothelial cells, thus corroborating its role in the early steps of inflammation. [source] Suppression of liver regeneration and hepatocyte proliferation in hepatocyte-targeted glypican 3 transgenic mice,HEPATOLOGY, Issue 3 2010Bowen Liu Glypican 3 (GPC3) belongs to a family of glycosylphosphatidylinositol-anchored, cell-surface heparan sulfate proteoglycans. GPC3 is overexpressed in hepatocellular carcinoma. Loss-of-function mutations of GPC3 result in Simpson-Golabi-Behmel syndrome, an X-linked disorder characterized by overgrowth of multiple organs, including the liver. Our previous study showed that GPC3 plays a negative regulatory role in hepatocyte proliferation, and this effect may involve CD81, a cell membrane tetraspanin. To further investigate GPC3 in vivo, we engineered transgenic (TG) mice overexpressing GPC3 in the liver under the control of the albumin promoter. GPC3 TG mice with hepatocyte-targeted, overexpressed GPC3 developed normally in comparison with their nontransgenic littermates but had a suppressed rate of hepatocyte proliferation and liver regeneration after partial hepatectomy. Moreover, gene array analysis revealed a series of changes in the gene expression profiles in TG mice (both in normal mice and during liver regeneration). In unoperated GPC3 TG mice, there was overexpression of runt related transcription factor 3 (7.6-fold), CCAAT/enhancer binding protein alpha (2.5-fold), GABA A receptor (2.9-fold), and wingless-related MMTV integration site 7B (2.8-fold). There was down-regulation of insulin-like growth factor binding protein 1 (8.4-fold), Rab2 (5.6-fold), beta-catenin (1.7-fold), transforming growth factor beta type I (3.1-fold), nodal (1.8-fold), and yes-associated protein (1.4-fold). Changes after hepatectomy included decreased expression in several cell cycle,related genes. Conclusion: Our results indicate that in GPC3 TG mice, hepatocyte overexpression of GPC3 suppresses hepatocyte proliferation and liver regeneration and alters gene expression profiles, and potential cell cycle,related proteins and multiple other pathways are involved and affected. (HEPATOLOGY 2010;52:1060,1067) [source] A coordinated approach to cutaneous wound healing: vibrational microscopy and molecular biologyJOURNAL OF CELLULAR AND MOLECULAR MEDICINE, Issue 5b 2008K. L. Andrew Chan Abstract The repair of cutaneous wounds in the adult body involves a complex series of spatially and temporally organized processes to prevent infection and restore homeostasis. Three characteristic phases of wound repair (inflammation, proliferation including re-epithelialization and remodelling) overlap in time and space. We have utilized a human skin wound-healing model to correlate changes in genotype and pheno-type with infrared (IR) and confocal Raman spectroscopic images during the re-epithelialization of excisional wounds. The experimental protocols validated as IR images clearly delineate the keratin-rich migrating epithelial tongue from the collagen-rich wound bed. Multivariate statistical analysis of IR datasets acquired 6 days post-wounding reveal subtle spectral differences that map to distinct spatial distributions, which are correlated with immunofluorescent staining patterns of different keratin types. Images computed within collagen-rich regions expose complementary spatial patterns and identify elastin in the wound bed. The temporal sequence of events is explored through a comparison of gene array analysis with confocal Raman microscopy. Our approach demonstrates the feasibility of acquiring detailed molecular structure information from the various proteins and their subclasses involved in the wound-healing process. [source] | ||||||||||