Inhibition of Elastase or SDF-1/CXCR4 Axis Promotes Differentiation of Human AML Cells.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 1891-1891
Author(s):  
Sigal Tavor ◽  
Jasmine Jacob-Hirsch ◽  
Manny Eisenbach ◽  
Sigi Kay ◽  
Shoshana Baron ◽  
...  

Abstract Elastase, along with other azurophil granule proteins like proteinase 3 regulates normal and leukemic granulopoiesis in an un-defined mechanism. We have recently showed that human acute myeloid leukemic (AML) cells constitutively express and secrete stromal derived factor 1 (SDF-1) dependent cell surface elastase, which regulates their migration and proliferation. To elucidate the molecular events and genes regulated by elastase and SDF-1/CXCR4 axis in AML cells, we examined gene expression of U937 AML cell line treated with neutralizing anti-CXCR4 Abs or elastase inhibitor (EI) compared to untreated cells, using DNA microarray technology. Unsupervised hierarchical clustering analysis showed very similar gene expression profiles of EI and anti CXCR4 Abs treated cells as compared to control. 230 of 8400 genes interrogated were repressed, and 164 were induced after culturing AML cells in the presence of EI or anti CXCR4 Abs at different time points as compared to untreated cells. Inhibition of elastase or CXCR4 was accompanied by down regulation of the transcripts of primary granule proteins. Functional classification of elastase or SDF-1/CXCR4 axis regulated genes revealed downregulation of HOXA9, HOXA10, ETS2, as well as other transcription factors that are over expressed in AML and are important for the development of leukemia. Whereas, transcriptional factors and regulators known to be induced during myeloid differentiation like C/EBPε, ID1, RUNX3 and HHEX were up-regulated in treated cells. Expression patterns of apoptosis genes indicated decline in death control by the p53 dependent pathway and a more prominent control by mitochondrial mediated apoptotic pathway like bcl2 related genes. In addition, receptors for interleukins, growth factors (G-CSFR and GM-CSF), complement component (C1QR1) were upregulated in the treated cells. In contrast, FLT-3, a growth factor receptor stimulating growth of early progenitor cells and AML blasts, was down regulated in AML cell treated with EI or anti CXCR4 Abs. These data were confirmed by real time PCR for selected marker genes of granulocytic differentiation. Interestingly, many of the differentially expressed genes were common to the transcriptional program of normal terminal granulocytic differentiation (Theilgaard-Monch & Borregarrd 2005. Blood 105:1785) suggesting that inhibition of elastase may induce differentiation in AML cells. Thus we further analyzed the effect of elastase inhibition on AML cell differentiation and growth. Treatment of HL60 AML cell line with EI triggered a proliferative arrest, apoptosis and mimicked terminal granulocytic differentiation, including morphologic changes, increased CD11b expression, and the ability to produce oxidative bursts. In summary, our study showed that inhibition of elastase or SDF-1/CXCR4 axis in AML cells affects similar pathways related to differentiation and malignant transformation, implying a critical role for those molecules in regulating leukemic development. Repression of elastase decreases proliferation and induces differentiation of AML cells, suggesting a potential new therapeutic approach for AML.

2018 ◽  
Vol 92 (23) ◽  
Author(s):  
Anita Shrestha ◽  
Kan Bao ◽  
Yun-Ru Chen ◽  
Wenbo Chen ◽  
Ping Wang ◽  
...  

ABSTRACTThe baculovirusAutographa californica multiple nucleopolyhedrovirus(AcMNPV) is a large double-stranded DNA (dsDNA) virus that encodes approximately 156 genes and is highly pathogenic to a variety of larval lepidopteran insects in nature. Oral infection of larval midgut cells is initiated by the occlusion-derived virus (ODV), while secondary infection of other tissues is mediated by the budded virus (BV). Global viral gene expression has been studied in detail in BV-infected cell cultures, but studies of ODV infection in the larval midgut are limited. In this study, we examined expression of the ∼156 AcMNPV genes inTrichoplusia nimidgut tissue using a transcriptomic approach. We analyzed expression profiles of viral genes in the midgut and compared them with profiles from aT. nicell line (Tnms42). Several viral genes (p6.9,orf76,orf75,pp31,Ac-bro,odv-e25, andodv-ec27) had high expression levels in the midgut throughout the infection. Also, the expression of genes associated with occlusion bodies (polhandp10) appeared to be delayed in the midgut in comparison with the cell line. Comparisons of viral gene expression profiles revealed remarkable similarities between the midgut and cell line for most genes, although substantial differences were observed for some viral genes. These included genes associated with high level BV production (fp-25k), acceleration of systemic infection (v-fgf), and enhancement of viral movement (arif-1/orf20). These differential expression patterns appear to represent specific adaptations for virus infection and transmission through the polarized cells of the lepidopteran midgut.IMPORTANCEBaculoviruses such as AcMNPV are pathogens that are natural regulators of certain insect populations. Baculovirus infections are biphasic, with a primary phase initiated by oral infection of midgut epithelial cells by occlusion-derived virus (ODV) virions and a secondary phase in which other tissues are infected by budded-virus (BV) virions. While AcMNPV infections in cultured cells have been studied extensively, comparatively little is known regarding primary infection in the midgut. In these studies, we identified gene expression patterns associated with ODV-mediated infection of the midgut inTrichoplusia niand compared those results with prior results from BV-infected cultured cells, which simulate secondary infection. These studies provide a detailed analysis of viral gene expression patterns in the midgut, which likely represent specific viral strategies to (i) overcome or avoid host defenses in the gut and (ii) rapidly move infection from the midgut, into the hemocoel to facilitate systemic infection.


2021 ◽  
Author(s):  
Nimrod Bernat ◽  
Rianne Campbell ◽  
Hyungwoo Nam ◽  
Mahashweta Basu ◽  
Tal Odesser ◽  
...  

The ventral pallidum (VP), a major component of the basal ganglia, plays a critical role in motivational disorders. It sends projections to many different brain regions but it is not yet known whether and how these projections differ in their cellular properties, gene expression patterns, connectivity and role in reward seeking. In this study, we focus on four major outputs of the VP - to the lateral hypothalamus (LH), ventral tegmental area (VTA), mediodorsal thalamus (MDT), and lateral habenula (LHb) - and examine the differences between them in 1) baseline gene expression profiles using projection-specific RNA-sequencing; 2) physiological parameters using whole-cell patch clamp; and 3) their influence on cocaine reward using chemogenetic tools. We show that these four VP efferents differ in all three aspects and highlight specifically differences between the projections to the LH and the VTA. These two projections originate largely from separate populations of neurons, express distinct sets of genes related to neurobiological functions, and show opposite physiological and behavioral properties. Collectively, our data demonstrates for the first time that VP neurons exhibit distinct molecular and cellular profiles in a projection-specific manner, suggesting that they represent different cell types.


2021 ◽  
Author(s):  
Chaohao Gu ◽  
Zhandong Liu

Abstract Spatial gene-expression is a crucial determinant of cell fate and behavior. Recent imaging and sequencing-technology advancements have enabled scientists to develop new tools that use spatial information to measure gene-expression at close to single-cell levels. Yet, while Fluorescence In-situ Hybridization (FISH) can quantify transcript numbers at single-cell resolution, it is limited to a small number of genes. Similarly, slide-seq was designed to measure spatial-expression profiles at the single-cell level but has a relatively low gene-capture rate. And although single-cell RNA-seq enables deep cellular gene-expression profiling, it loses spatial information during sample-collection. These major limitations have stymied these methods’ broader application in the field. To overcome spatio-omics technology’s limitations and better understand spatial patterns at single-cell resolution, we designed a computation algorithm that uses glmSMA to predict cell locations by integrating scRNA-seq data with a spatial-omics reference atlas. We treated cell-mapping as a convex optimization problem by minimizing the differences between cellular-expression profiles and location-expression profiles with an L1 regularization and graph Laplacian based L2 regularization to ensure a sparse and smooth mapping. We validated the mapping results by reconstructing spatial- expression patterns of well-known marker genes in complex tissues, like the mouse cerebellum and hippocampus. We used the biological literature to verify that the reconstructed patterns can recapitulate cell-type and anatomy structures. Our work thus far shows that, together, we can use glmSMA to accurately assign single cells to their original reference-atlas locations.


PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e1814 ◽  
Author(s):  
Keren Maor-Landaw ◽  
Oren Levy

It is well-established that there is a hierarchy of susceptibilities amongst coral genera during heat-stress. However, molecular mechanisms governing these differences are still poorly understood. Here we explored if specific corals possessing different morphologies and different susceptibilities to heat stress may manifest varied gene expression patterns. We examined expression patterns of seven genes in the branching coralsStylophora pistillataandAcropora eurystomaand additionally in the massive robust coral,Poritessp. The tested genes are representatives of key cellular processes occurring during heat-stress in Cnidaria: oxidative stress, ER stress, energy metabolism, DNA repair and apoptosis. Varied response to the heat-stress, in terms of visual coral paling, algal maximum quantum yield and host gene expression was evident in the different growth forms. The two branching corals exhibited similar overall responses that differed from that of the massive coral.A. eurystomathat is considered as a susceptible species did not bleach in our experiment, but tissue sloughing was evident at 34 °C. Interestingly, in this species redox regulation genes were up-regulated at the very onset of the thermal challenge. InS. pistillata, bleaching was evident at 34 °C and most of the stress markers were already up-regulated at 32 °C, either remaining highly expressed or decreasing when temperatures reached 34 °C. The massivePoritesspecies displayed severe bleaching at 32 °C but stress marker genes were only significantly elevated at 34 °C. We postulate that by expelling the algal symbionts fromPoritestissues, oxidation damages are reduced and stress genes are activated only at a progressed stage. The differential gene expression responses exhibited here can be correlated with the literature well-documented hierarchy of susceptibilities amongst coral morphologies and genera in Eilat’s coral reef.


2011 ◽  
Vol 29 (4_suppl) ◽  
pp. 232-232
Author(s):  
S. X. Wang ◽  
J. Wang ◽  
M. S. Beg ◽  
E. Ozhegov ◽  
A. X. Qu ◽  
...  

232 Background: Cancer stroma plays a critical role in tumorigenesis. Microarrays are widely used to study gene expression patterns in tumor frozen tissue to explore tumorigenesis and predict recurrence. Here we explored the feasibility of applying microarrays to tumor stroma using FFPE specimens. Methods: Ten samples were obtained from one colon and one pancreatic cancer specimen. Tumor stroma and normal stroma were microdissected. RNA was extracted, amplified, and labeled using Nugene FFPE kit, with array analysis using Affymetrix Human Gene 1.0. To assess reproducibility, each stroma sample was run twice in parallel. To test the reproducibility of sampling, the specimen was microdissected twice at a different stroma location. GenePattern software was used; correlation between parallel samples and the repeat dissection samples was calculated and ComparativeMarkerSelection program with two-sided T test was used to study gene profiles in pancreatic and colon stroma. To validate the array results, the profile differences were analyzed against public databases. Results: The correlation between the duplicate samples was in the range of 0.978-0.988. The correlation between the original versus the repeat dissection at a different stroma site was 0.953-0.967. 19,319 probes with gene annotation were examined, and pancreatic stroma was compared to colon stroma. We found that 90% of these genes were expressed at similar levels. Using a cutoff of 1.3, we identified 50 genes that were expressed greater than 30% in pancreatic stroma compared to colon stroma. We researched these 50 genes against GeneNote, GNF, Unigene and SAGE databases. Upregulation of 95% of these genes in pancreatic stroma is consistent with the public databases. Moreover, among these genes we identified PNLIP, CPB1 CPA2, PRSS1/PRSS2, AMY1A, AMY1B, AMY1C, and AMY2A, known to be highly expressed in pancreatic tissue. Conclusions: Gene expression microarray is a tool that can be effectively used to analyze normal and tumor stroma in GI cancer. FFPE tissue is suitable for such an analysis, as evidenced by high reproducibility and biologic consistency of the obtained data. No significant financial relationships to disclose.


Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 1621-1621
Author(s):  
Sigal Tavor ◽  
Manny Eisenbach ◽  
Jasmine Jacob-Hirsch ◽  
Tammar Golan ◽  
Isabelle Petit ◽  
...  

Abstract The chemokine stromal cell-derived factor-1 (SDF-1) and its receptor, CXCR4, participate in the retention of AML cells within the bone marrow microenvironment and their release into the circulation. We previously showed that the expression of cell surface elastase in AML cells is dependent on the SDF-1/CXCR4 axis, giving a first evidence for the association between the SDF-1 and elastase pathways. In the present study, we hypothesized that inhibition of the SDF-1/CXCR4 axis or elastase may regulate similar pathways and genes in AML cells. In order to test our hypothesis, we compared gene expression profiles of U937 AML cells that express high level of membrane CXCR4, treated with neutralizing CXCR4 mAb or elastase inhibitor (EI), with non-treated cells, by employing gene-array technology. Unsupervised hierarchical clustering analysis demonstrated similar gene expression profiles of anti-CXCR4 antibody or EI treated cells, as compared to control. Analysis of the 364 genes that were differentially expressed in both anti CXCR4 mAb or EI treated cells under both treatment agents identified genes that correspond to the transcriptional profiles of differentiated myeloid cells in a significantly high prevalence. Quantitative Real-time RT-PCR for 4 selected genes C/EBPe, FLT3, HOXA9 and G-CSFR, demonstrated gene expression profiles identical to the microarray expression profiles. Given thus, we further analyzed the effect of CXCR4 inhibition on AML cell growth and differentiation using the antagonist AMD3100. AMD3100 arrested proliferation in five AML cell lines as was suggested by proliferation assay, cell cycle and caspase 3 activity analyses. Moreover, cell differentiation was demonstrated by: Modifications in cell morphology, Increased expression of myeloid differentiation antigens Acquisition of the ability to produce oxidative bursts An increase in DNA ploidy in megakaryoblasts. Our study defines a new role for the SDF-1/CXCR4 axis in the regulation of leukemic cell survival and differentiation.


Sarcoma ◽  
2010 ◽  
Vol 2010 ◽  
pp. 1-14 ◽  
Author(s):  
Silke Brüderlein ◽  
Joshua B. Sommer ◽  
Paul S. Meltzer ◽  
Sufeng Li ◽  
Takuya Osada ◽  
...  

Immortal tumor cell lines are an important model system for cancer research, however, misidentification and cross-contamination of cell lines are a common problem. Seven chordoma cell lines are reported in the literature, but none has been characterized in detail. We analyzed gene expression patterns and genomic copy number variations in five putative chordoma cell lines (U-CH1, CCL3, CCL4, GB60, and CM319). We also created a new chordoma cell line, U-CH2, and provided genotypes for cell lines for identity confirmation. Our analyses revealed that CCL3, CCL4, and GB60 are not chordoma cell lines, and that CM319 is a cancer cell line possibly derived from chordoma, but lacking expression of key chordoma biomarkers. U-CH1 and U-CH2 both have gene expression profiles, copy number aberrations, and morphology consistent with chordoma tumors. These cell lines also harbor genetic changes, such as loss of p16, MTAP, or PTEN, that make them potentially useful models for studying mechanisms of chordoma pathogenesis and for evaluating targeted therapies.


2021 ◽  
Author(s):  
Chaohao Gu ◽  
Zhandong Liu

AbstractSpatial gene-expression is a crucial determinant of cell fate and behavior. Recent imaging and sequencing-technology advancements have enabled scientists to develop new tools that use spatial information to measure gene-expression at close to single-cell levels. Yet, while Fluorescence In-situ Hybridization (FISH) can quantify transcript numbers at single-cell resolution, it is limited to a small number of genes. Similarly, slide-seq was designed to measure spatial-expression profiles at the single-cell level but has a relatively low gene-capture rate. And although single-cell RNA-seq enables deep cellular gene-expression profiling, it loses spatial information during sample-collection. These major limitations have stymied these methods’ broader application in the field. To overcome spatio-omics technology’s limitations and better understand spatial patterns at single-cell resolution, we designed a computation algorithm that uses glmSMA to predict cell locations by integrating scRNA-seq data with a spatialomics reference atlas. We treated cell-mapping as a convex optimization problem by minimizing the differences between cellular-expression profiles and location-expression profiles with a L1 regularization and graph Laplacian based L2 regularization to ensure a sparse and smooth mapping. We validated the mapping results by reconstructing spatial-expression patterns of well-known marker genes in complex tissues, like the mouse cerebellum and hippocampus. We used the biological literature to verify that the reconstructed patterns can recapitulate cell-type and anatomy structures. Our work thus far shows that, together, we can use glmSMA to accurately assign single cells to their original reference-atlas locations.


2021 ◽  
Vol 22 (4) ◽  
pp. 1901
Author(s):  
Brielle Jones ◽  
Chaoyang Li ◽  
Min Sung Park ◽  
Anne Lerch ◽  
Vimal Jacob ◽  
...  

Mesenchymal stromal cells derived from the fetal placenta, composed of an amnion membrane, chorion membrane, and umbilical cord, have emerged as promising sources for regenerative medicine. Here, we used next-generation sequencing technology to comprehensively compare amniotic stromal cells (ASCs) with chorionic stromal cells (CSCs) at the molecular and signaling levels. Principal component analysis showed a clear dichotomy of gene expression profiles between ASCs and CSCs. Unsupervised hierarchical clustering confirmed that the biological repeats of ASCs and CSCs were able to respectively group together. Supervised analysis identified differentially expressed genes, such as LMO3, HOXA11, and HOXA13, and differentially expressed isoforms, such as CXCL6 and HGF. Gene Ontology (GO) analysis showed that the GO terms of the extracellular matrix, angiogenesis, and cell adhesion were significantly enriched in CSCs. We further explored the factors associated with inflammation and angiogenesis using a multiplex assay. In comparison with ASCs, CSCs secreted higher levels of angiogenic factors, including angiogenin, VEGFA, HGF, and bFGF. The results of a tube formation assay proved that CSCs exhibited a strong angiogenic function. However, ASCs secreted two-fold more of an anti-inflammatory factor, TSG-6, than CSCs. In conclusion, our study demonstrated the differential gene expression patterns between ASCs and CSCs. CSCs have superior angiogenic potential, whereas ASCs exhibit increased anti-inflammatory properties.


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