Metsada Pasmanik-Chor

Tel Aviv University, Tell Afif, Tel Aviv, Israel

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Publications (47)226.47 Total impact

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    ABSTRACT: Women diagnosed with pregnancy associated breast cancer often have advanced cancer with metastases and reduced expression of ERα compared to non-pregnant women. Nevertheless, metastases to the placenta are uncommon. Previously, we demonstrated that breast cancer cells (MCF-7/T47D) migrated from ex vivo human placental explant implantation sites. We aimed to analyze the effect of factors produced during placental implantation or as a result of the interaction between the implanted placentae to cancer cells on cancer cells migration and aggressiveness. We collected supernatants from implanted placentae and placental-breast cancer cells cocultures and analyzed their effects on cancer cells phenotype and pathways. Supernatants collected from breast cancer cells served as controls. We found that supernatants collected from implanted placentae induced modest cancer cells migration that was not accompanied by epithelial to mesenchymal transition (EMT), supported breast cancer cells survival and elevated MCF-7 cell number. The coculture supernatant induced excessive motility and EMT of the MCF-7 cells. This EMT was mediated by Smad3 and JNK/ERK activation. Both placenta and coculture supernatants reduced ERα expression in the cancer cells. Finally, we showed that MCF-7 cocultured with the human placental explants underwent continuous activation of JNK and Smad3 pathways and the EMT process, which led to their migration away from the placental implantation sites. These findings may explain the reduced ERα and elevated metastases found in breast cancer during pregnancy and highlights pathways involved in it.
    Clinical & experimental metastasis. 10/2014;
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    ABSTRACT: Chronic myeloid leukemia (CML) is a disorder of hematopoietic stem cell carrying the Philadelphia (Ph) chromosome and an oncogenic BCR-ABL fusion gene. Tyrosine kinase inhibitors (TKIs) of the BCR-ABL kinase are the treatment of choice for CML patients. Imatinib was the first TKI used in clinical practice with excellent results. MicroRNAs (miRNAs) are short non-coding regulatory RNAs that control gene expression and play an important role in cancer development and progression. Aberrant miRNA expression profiles have been shown to be characteristic of many cancers. Here, we demonstrate that miR-30e is expressed at low levels in CML cell lines and patient samples. Bioinformatics analysis reveals a putative target site for miR-30e in the 3'-untranslated region (UTR) of the ABL gene. In agreement, luciferase assay verified that miR-30e directly targets ABL. Enforced expression of miR-30e in K562 cells suppressed proliferation and induced apoptosis of these cells and sensitized them to imatinib treatment. These findings strongly suggest that miR-30e acts as a tumor suppressor by down regulating BCR-ABL expression. Up-regulation of miR-30e in CML cells may therefore have a therapeutic efficacy against this disease.
    Cancer letters. 10/2014;
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    ABSTRACT: To evaluate molecular profiles in the small bowel (SB) mucosa proximal to the pouch in ulcerative colitis (UC) patients after pouch surgery.
    Gut 06/2014; · 10.73 Impact Factor
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    ABSTRACT: The liver has a remarkable capacity to regenerate after injury; yet, the role of macrophages (MF) in this process remains controversial mainly due to difficulties in distinguishing between different MF subsets. In this study, we used a murine model of acute liver injury induced by overdose of N-acetyl-p-aminophenol (APAP) and defined three distinct MF subsets that populate the liver following injury. Accordingly, resident Kupffer cells (KC) were significantly reduced upon APAP challenge and started recovering by self-renewal at resolution phase without contribution of circulating Ly6C(hi) monocytes. The latter were recruited in a CCR2- and M-CSF-mediated pathway at the necroinflammatory phase and differentiated into ephemeral Ly6C(lo) MF subset at resolution phase. Moreover, their inducible ablation resulted in impaired recovery. Microarray-based molecular profiling uncovered high similarity between steady-state KC and those recovered at the resolution phase. In contrast, KC and monocyte-derived MF displayed distinct prorestorative genetic signature at the resolution phase. Finally, we show that infiltrating monocytes acquire a prorestorative polarization manifested by unique expression of proangiogenesis mediators and genes involved with inhibition of neutrophil activity and recruitment and promotion of their clearance. Collectively, our results present a novel phenotypic, ontogenic, and molecular definition of liver-MF compartment following acute injury.
    Journal of immunology (Baltimore, Md. : 1950). 06/2014;
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    ABSTRACT: High blood and tissue concentrations of glucose and advanced glycation end-products are believed to play an important role in the development of vascular complications in patients with diabetes mellitus (DM) and chronic kidney disease. microRNAs (miRNA) are non-coding RNAs that regulate gene expression in a sequence specific manner. miRNA are involved in various biological processes and become novel biomarkers, modulators and therapeutic targets for diseases such as cancer, atherosclerosis, and DM. Calcitriol (the active form of vitamin D) may inhibit endothelial proliferation, blunt angiogenesis, and be a cardioprotective agent. Calcitriol deficiency is a risk factor for DM and hypertension. The aim of this project was to study the miRNA microarray expression changes in human umbilical vein endothelial cells (HUVEC) treated in a diabetic-like environment with the addition of calcitriol. HUVEC were treated for 24 h with 200 mug/ml human serum albumin (HSA) and 100 mg/dl glucose (control group) or 200 mug/ml AGE-HSA, and 250 mg/dl glucose (diabetic-like environment), and physiological concentrations (10-10 mol/l) of calcitriol. miRNA microarray analysis and real time PCR to validate the miRNA expression profile and mRNA target gene expression were carried out. Compared to control, 31 mature human miRNA were differentially expressed in the presence of a diabetic-like environment. Addition of physiological concentrations of calcitriol revealed 39 differentially expressed mature human miRNA. MiR-181c, miR-15a, miR-20b, miR-411, miR-659, miR-126 and miR-510 were selected for further analysis because they are known to be modified in DM and in other biological disorders. The predicted targets of these miRNA (such as KLF6, KLF9, KLF10, TXNIP and IL8) correspond to molecular and biological processes such as immune and defense responses, signal transduction and regulation of RNA. This study identified novel miRNA in the field of diabetic vasculopathy and might provide new information about the effect of vitamin D on gene regulation induced by a diabetic-like environment. New gene targets that are part of the molecular mechanism and the therapeutic treatment in diabetic vasculopathy are highlighted.
    Cardiovascular Diabetology 01/2014; 13(1):8. · 4.21 Impact Factor
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    Jonathan Witztum, Erez Persi, David Horn, Metsada Pasmanik-Chor, Benny Chor
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    ABSTRACT: The availability of many complete, annotated proteomes enables the systematic study of the relationships between protein conservation and functionality. We explore this question based solely on the presence or absence of protein homologues (a.k.a. conservation profiles). We study 18 metazoans, from two distinct points of view: the human's and the fly's. Using the GOrilla gene ontology (GO) analysis tool, we explore functional enrichment of the "universal proteins", those with homologues in all 17 other species, and of the "non-universal proteins". A large number of GO terms are strongly enriched in both human and fly universal proteins. Most of these functions are known to be essential. A smaller number of GO terms, exhibiting markedly different properties, are enriched in both human and fly non-universal proteins. We further explore the non-universal proteins, whose conservation profiles are consistent with the "tree of life" (TOL consistent), as well as the TOL inconsistent proteins. Finally, we applied Quantum Clustering to the conservation profiles of the TOL consistent proteins. Each cluster is strongly associated with one or a small number of specific monophyletic clades in the tree of life. The proteins in many of these clusters exhibit strong functional enrichment associated with the "life style" of the related clades. Most previous approaches for studying function and conservation are "bottom up", studying protein families one by one, and separately assessing the conservation of each. By way of contrast, our approach is "top down". We globally partition the set of all proteins hierarchically, as described above, and then identify protein families enriched within different subdivisions. While supporting previous findings, our approach also provides a tool for discovering novel relations between protein conservation profiles, functionality, and evolutionary history as represented by the tree of life.
    PLoS ONE 01/2014; 9(3):e90282. · 3.53 Impact Factor
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    ABSTRACT: The HeatMapViewer is a BioJS component that lays-out and renders two-dimensional (2D) plots or heat maps that are ideally suited to visualize matrix formatted data in biology such as for the display of microarray experiments or the outcome of mutational studies and the study of SNP-like sequence variants. It can be easily integrated into documents and provides a powerful, interactive way to visualize heat maps in web applications. The software uses a scalable graphics technology that adapts the visualization component to any required resolution, a useful feature for a presentation with many different data-points. The component can be applied to present various biological data types. Here, we present two such cases - showing gene expression data and visualizing mutability landscape analysis. Availability:https://github.com/biojs/biojs; http://dx.doi.org/10.5281/zenodo.7706.
    F1000Research. 01/2014; 3:48.
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    ABSTRACT: TOR proteins reside in two distinct complexes, TOR complex 1 and 2 (TORC1 and TORC2) that are central for the regulation of cellular growth, proliferation and survival. TOR is also the target for the immunosuppressive and anti-cancer drug rapamycin. In Schizosaccharaomyces pombe, disruption of the TSC complex, mutations in which can lead to the Tuberous Sclerosis syndrome in humans, results in a rapamycin sensitive phenotype under poor nitrogen conditions. We show here that the sensitivity to rapamycin is mediated via inhibition of TORC1 and suppressed by overexpression of isp7(+), a member of the family of 2-oxoglutarate-Fe(II) dependent oxygenases. The transcript level of isp7(+) is negatively regulated by TORC1 but positively regulated by TORC2. Yet, we find extensive similarity between the transcriptome of cells disrupted for isp7(+) and cells mutated in the catalytic subunit of TORC1. Moreover, Isp7 regulates amino acid permease expression similarly to TORC1 and in contrast to TORC2. Overexpression of isp7(+) induces TORC1-dependent phosphorylation of ribosomal protein Rps6, while inhibiting TORC2-dependent phosphorylation and activation of the AGC-like kinase Gad8. Taken together, our findings suggest a central role for Isp7 in amino acid homeostasis and the presence of isp7(+)-dependent regulatory loops that affect both TORC1 and TORC2.
    Molecular and cellular biology 12/2013; · 6.06 Impact Factor
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    ABSTRACT: Pouchitis may develop in patients with ulcerative colitis undergoing pouch surgery. We aimed to evaluate the de novo inflammation developing in the ileal pouch, hypothesizing that it may be similar to ileitis in Crohn's disease (CD). Patients with ulcerative colitis pouch were prospectively recruited, stratified according to disease behavior into normal pouch, chronic pouchitis, and Crohn's-like disease of the pouch groups, and compared with controls. Gene expression analysis was performed using microarrays, validated by real-time polymerase chain reaction. Gene ontology and clustering were evaluated using bioinformatic tools. Sixty-six subjects were recruited. Although in ulcerative colitis ileum there were no significant gene expression alterations, patients with normal pouch had 168 significant alterations (fold change ≥ 2, corrected P ≤ 0.05). In chronic pouchitis and Crohn's-like disease of the pouch, 490 and 1152 alterations were detected, respectively. High degree of overlap in gene expression alterations between the pouch subgroups was demonstrated. The magnitude of change correlated with pouch disease behavior. Gene expression profiles were more reflective of disease behavior compared with inflammatory indices. CD ileitis had 358 alterations, with a 90% overlap with pouchitis. Gene ontology analyses revealed multiple biological processes associated with pouch inflammation, including response to chemical stimulus, small molecule metabolic and immune system processes, and specific infection-related pathways such as Staphylococcus aureus, leishmaniasis, and tuberculosis. Gene alterations in pouch inflammation and CD overlap, suggesting that inflammatory bowel diseases is a spectrum, rather than distinct diseases. Pouchitis may serve as a model of CD. The novel pathways associated with inflammatory bowel diseases may decipher pathophysiology and suggest targets for intervention.
    Inflammatory Bowel Diseases 10/2013; · 5.12 Impact Factor
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    ABSTRACT: The combination of microcephaly, pyramidal signs, abnormal corpus callosum, and intellectual disability presents a diagnostic challenge. We describe an autosomal recessive disorder characterized by microcephaly, pyramidal signs, thin corpus callosum, and intellectual disability. We previously mapped the locus for this disorder to 8q23.2-q24.12; the candidate region included 22 genes. We performed Sanger sequencing of 10 candidate genes; to ensure other genes in the candidate region do not harbor mutations, we sequenced the exome of one affected individual. We identified two homozygous missense changes, p.Thr186Arg and p.Pro416His in TAF2, which encodes a multisubunit cofactor for TFIID-dependent RNA polymerase II-mediated transcription, in all affected individuals. We propose that the disorder is caused by the more conserved mutation p.Thr186Arg, with the second sequence change identified, p.Pro416His, possibly further negatively affecting the function of the protein. However, it is unclear which of the two changes, or maybe both, represents the causative mutation. A single missense mutation in TAF2 in a family with microcephaly and intellectual disability was described in a large-scale study reporting on the identification of 50 novel genes. We suggest that a mutation in TAF2 can cause this syndrome.
    Pediatric Neurology 09/2013; · 1.42 Impact Factor
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    ABSTRACT: Epileptic encephalopathies are genetically heterogeneous severe disorders in which epileptic activity contributes to neurological deterioration. We studied two unrelated children presenting with a distinctive early-onset epileptic encephalopathy characterized by refractory epilepsy and absent developmental milestones, as well as thick and short corpus callosum and persistent cavum septum pellucidum on brain MRI. Using whole-exome sequencing, we identified biallelic mutations in seizure threshold 2 (SZT2) in both affected children. The causative mutations include a homozygous nonsense mutation and a nonsense mutation together with an exonic splice-site mutation in a compound-heterozygous state. The latter mutation leads to exon skipping and premature termination of translation, as shown by RT-PCR in blood RNA of the affected boy. Thus, all three mutations are predicted to result in nonsense-mediated mRNA decay and/or premature protein truncation and thereby loss of SZT2 function. Although the molecular role of the peroxisomal protein SZT2 in neuronal excitability and brain development remains to be defined, Szt2 has been shown to influence seizure threshold and epileptogenesis in mice, consistent with our findings in humans. We conclude that mutations in SZT2 cause a severe type of autosomal-recessive infantile encephalopathy with intractable seizures and distinct neuroradiological anomalies.
    The American Journal of Human Genetics 08/2013; · 11.20 Impact Factor
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    ABSTRACT: BACKGROUND: It has recently been shown that microvesicles derived from activated T cells can stimulate human mast cells (MCs) to degranulate and release several cytokines. OBJECTIVE: The aim of this study was to characterize microvesicle-induced MC expression patterns. Through identification of unique cytokine and chemokine expression, we attempted to reveal pathogenetic roles for this pathway of MC activation. METHODS: T cell-derived microvesicles were labeled with PKH67 to allow visualization of their interaction with human MCs. Consequent gene expression profiling was studied by using a whole-genome microarray and analyzed for identification of cellular pathway clusters. Expression of 3 selected genes, chemokine (C-C motif) ligand 3 (CCL3), chemokine (C-C motif) ligand 7 (CCL7), and IL24, was validated by means of quantitative RT-PCR and specific ELISA. IL24, which has not been recognized heretofore in MCs, was also tested for its effect on keratinocyte signal transducer and activator of transcription 3 phosphorylation and for its presence in MCs in psoriatic skin lesions. RESULTS: Uptake and internalization of activated T cell-derived microvesicles into human MCs occurred within 24 hours. Microvesicles induced the upregulation of several clusters of genes, notably those that are cytokine related. Among these, IL24 appeared to be a hallmark of microvesicle-induced activation. MC-derived IL-24, in turn, activates keratinocytes in vitro, as manifested by signal transducer and activator of transcription 3 (STAT3) phosphorylation, and is produced in MCs within psoriatic lesions. CONCLUSION: Production of IL-24 is a unique feature of microvesicle-induced MC activation because its production by these cells has not been recognized thus far. We propose that this MC-derived cytokine might contribute to the pathologic findings in T cell-mediated skin inflammation.
    The Journal of allergy and clinical immunology 06/2013; · 12.05 Impact Factor
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    ABSTRACT: During development, tissue-specific transcription factors regulate both protein-coding and non-coding genes to control differentiation. Recent studies have established a dual role for the transcription factor Pax6 as both an activator and repressor of gene expression in the eye, central nervous system, and pancreas. However, the molecular mechanism underlying the inhibitory activity of Pax6 is not fully understood. Here, we reveal that Trpm3 and the intronic microRNA gene miR-204 are co-regulated by Pax6 during eye development. miR-204 is probably the best known microRNA to function as a negative modulator of gene expression during eye development in vertebrates. Analysis of genes altered in mouse Pax6 mutants during lens development revealed significant over-representation of miR-204 targets among the genes up-regulated in the Pax6 mutant lens. A number of new targets of miR-204 were revealed, among them Sox11, a member of the SoxC family of pro-neuronal transcription factors, and an important regulator of eye development. Expression of Trpm/miR-204 and a few of its targets are also Pax6-dependent in medaka fish eyes. Collectively, this study identifies a novel evolutionarily conserved mechanism by which Pax6 controls the down-regulation of multiple genes through direct up-regulation of miR-204.
    PLoS Genetics 03/2013; 9(3):e1003357. · 8.52 Impact Factor
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    Dataset: Sobp2010
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    ABSTRACT: BACKGROUND: Intraductal papillary mucinous neoplasms (IPMN) represent a spectrum of tumors that range from low-grade (LG) dysplastic tumors to invasive cancer. Identification of IPMN at high risk for malignant transformation is important for the prevention and early treatment of pancreatic cancer. The roles of microRNA expression in the development of IPMN have not been extensively evaluated. METHODS: Expression patterns of 846 human microRNAs (miRNAs) was analyzed using microRNA microarray in 55 tissues, including LG IPMN (n = 10), moderate-grade (MG) IPMN (n = 5), high-grade (HG) IPMN (n = 5), invasive cancer with IPMN (IPMC; n = 10), pancreatic ductal adenocarcinoma without IPMN (PDA; n = 5), LG IPMN extracted from specimens that contain IPMC (LG_Ca; n = 10), and normal pancreatic tissues (n = 10). RESULTS: Fourteen miRNAs were differentially expressed in all IPMN tissues compared with normal pancreatic tissue. Expression level of 3 miRNAs was proportional to dysplasia level. Hierarchical clustering demonstrated grouping of 2 IPMN subgroups: LG and MG IPMN verses HG IPMN and IPMC. Expression of 15 miRNAs was significantly different between these groups. LG_Ca tissues clustered with the HG IPMC group, and 12 miRNAs were differentially expressed in LG_Ca, HG lesions, and IPMC compared with LG lesions. The expression patterns of selected miRNAs were validated using quantitative reverse-transcription real-time polymerase chain reaction. Hierarchical clustering demonstrated microRNA expression profile in IPMC was significantly different from PDA, suggesting that different pathways are involved in these cancer types. CONCLUSION: This study demonstrates that miRNAs are involved in the development and progression of IPMN. We identified potential targets for diagnosis, prognostication, and treatment of IPMN.
    Surgery 01/2013; · 3.37 Impact Factor
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    ABSTRACT: Background The combination of microcephaly, pyramidal signs, abnormal corpus callosum, and intellectual disability presents a diagnostic challenge. We describe an autosomal recessive disorder characterized by microcephaly, pyramidal signs, thin corpus callosum, and intellectual disability. Methods We previously mapped the locus for this disorder to 8q23.2-q24.12; the candidate region included 22 genes. We performed Sanger sequencing of 10 candidate genes; to ensure other genes in the candidate region do not harbor mutations, we sequenced the exome of one affected individual. Results We identified two homozygous missense changes, p.Thr186Arg and p.Pro416His in TAF2, which encodes a multisubunit cofactor for TFIID-dependent RNA polymerase II–mediated transcription, in all affected individuals. Conclusions We propose that the disorder is caused by the more conserved mutation p.Thr186Arg, with the second sequence change identified, p.Pro416His, possibly further negatively affecting the function of the protein. However, it is unclear which of the two changes, or maybe both, represents the causative mutation. A single missense mutation in TAF2 in a family with microcephaly and intellectual disability was described in a large-scale study reporting on the identification of 50 novel genes. We suggest that a mutation in TAF2 can cause this syndrome.
    Pediatric Neurology. 01/2013; 49(6):411–416.e1.
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    ABSTRACT: Aims: Human lymphoblastoid cell lines (LCLs) are a rich resource of information on human interindividual genomic, transcriptomic, proteomic and phenomic variations, and are therefore gaining popularity for pharmacogenomic studies. In the present study we demonstrate that genome-wide transcriptomic data from a small LCL panel from unrelated individuals is sufficient for detecting pairs of genes that exhibit highly correlated expression levels and may thus convey insights about coregulated genes. Materials & methods: RNA samples were prepared from LCLs representing 12 unrelated healthy adult female Caucasian donors. Transcript levels were determined with the Affymetrix Human Gene arrays. Expression-level correlations were searched using Partek(®) Genomics Suite™ and the R environment. Sequences of detected correlated gene pairs were compared for shared conserved 3´-UTR miRNA binding. Results: Most of the approximately 33,000 transcripts covered by the Affymetrix arrays showed closely similar expression levels in LCLs from unrelated donors. However, the expression levels of some transcripts showed large inter-individual variations. When comparing the expression levels of each of the top 1000 genes showing the largest interindividual expression variations against the others, two sets containing 156 and 4438 correlated gene pairs with false-discovery rates of 0.01 and 0.05 were detected, respectively. Similar analysis of another gene-expression data set from LCLs (GSE11582) indicated that 61 and 39% of identified pairs matched the pairs detected from our transcriptomic data, respectively. Shared conserved 3´-UTR miRNA binding sites were noted for 14-17% of the top 100 gene pairs, suggesting that regulation by miRNA may contribute to their coordinated expression. Conclusion: Probing genome-wide transcriptomic data sets of LCLs from unrelated individuals may detect coregulated genes, adding insights on cellular regulation by miRNAs. Original submitted 11 July 2012; Revision submitted 4 September 2012.
    Pharmacogenomics 12/2012; 13(16):1893-1904. · 3.86 Impact Factor
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    ABSTRACT: Ubiquitination plays a crucial role in neurodevelopment as exemplified by Angelman syndrome, which is caused by genetic alterations of the ubiquitin ligase-encoding UBE3A gene. Although the function of UBE3A has been widely studied, little is known about its paralog UBE3B. By using exome and capillary sequencing, we here identify biallelic UBE3B mutations in four patients from three unrelated families presenting an autosomal-recessive blepharophimosis-ptosis-intellectual disability syndrome characterized by developmental delay, growth retardation with a small head circumference, facial dysmorphisms, and low cholesterol levels. UBE3B encodes an uncharacterized E3 ubiquitin ligase. The identified UBE3B variants include one frameshift and two splice-site mutations as well as a missense substitution affecting the highly conserved HECT domain. Disruption of mouse Ube3b leads to reduced viability and recapitulates key aspects of the human disorder, such as reduced weight and brain size and a downregulation of cholesterol synthesis. We establish that the probable Caenorhabditis elegans ortholog of UBE3B, oxi-1, functions in the ubiquitin/proteasome system in vivo and is especially required under oxidative stress conditions. Our data reveal the pleiotropic effects of UBE3B deficiency and reinforce the physiological importance of ubiquitination in neuronal development and function in mammals.
    The American Journal of Human Genetics 11/2012; · 11.20 Impact Factor
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    ABSTRACT: Ovarian carcinoma patients are initially responsive to platinum-based therapy, but eventually become refractory to treatment due to the development of platinum chemoresistance. Elevated levels of interleukin-6 (IL-6) in the sera and ascites of these patients predict poor clinical outcome. Our goal was to analyze the interaction between cisplatin and cisplatin-resistant ovarian cancer cells, and to identify means of circumventing platinum resistance. We studied ovarian carcinoma cell lines and cells drawn from ovarian carcinoma patients. Gene array analyses were performed on ovarian carcinoma cells upon treatment with cisplatin, and the results were validated by ELISA and Western blotting (WB). Cytotoxicity assays were performed on anti-IL-6 Ab-, IL-6-, and cellular inhibitor of apoptosis 2 (cIAP-2) siRNA-treated cells, following cisplatin addition. Our results revealed a highly significant increase in IL-6 and cIAP-2 mRNA and protein levels upon treatment with cisplatin. WB analysis of cisplatin-treated cells exhibited decreased cIAP-2 expression level following anti-IL-6 Ab addition. Furthermore, IL-6 by itself, significantly increased cIAP-2 levels in ovarian carcinoma cells. Finally, cytotoxicity assays showed sensitization to cisplatin following the addition of IL-6 and cIAP-2 inhibitors. In conclusion, cisplatin treatment of ovarian carcinoma cells upregulates IL-6 and cIAP-2 levels while their inhibition significantly sensitizes them to cisplatin. Here, we present cIAP-2 as a novel inducer of platinum resistance in ovarian carcinoma cells, and suggest an axis beginning with an encounter between cisplatin and these cells, mediated sequentially by IL-6 and cIAP-2, resulting in cisplatin resistance. Consequently, we propose that combining IL-6/cIAP-2 inhibitors with cisplatin will provide new hope for ovarian carcinoma patients by improving the current treatment.
    Journal of Molecular Medicine 09/2012; · 4.77 Impact Factor
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    ABSTRACT: The milieu of the liver, and in particular hepatocyte-derived extracellular matrix (hECM), is a critical factor regulating development of liver metastases of colorectal cancer (CRC) cells. The present study has investigated genes altered by hECM in CRC cells and particularly by heparan sulfate chains of hepatocyte proteoglycans. Gene profiling analysis shows that after 2 days on hECM, 226 genes are up-regulated more than 2-fold in strongly metastatic SM cells, including genes involved in growth arrest and apoptosis, signal transduction, cell migration, proliferation, communication and angiogenesis, with activation of the erbB signaling network and p53 effectors. Genes down-regulated by hECM include genes involved in lipogenesis and the S phase of the cell cycle. Further studies exploring the kinetics of gene expression after 4 and 7 days culture on hECM show induction of EGF family members and of stem cell markers. In particular, hECM, but not collagen, increases mRNA expression of HB-EGF and colon stem cell marker leucine-rich repeat-containing G protein-coupled receptor 5 (LGR5). Expression of these genes is not induced by hECM depleted of the heparan sulfate chains of proteoglycans. Lastly, a specific cell population positive for cancer stem cell (CSC) markers LGR5, epCAM and CD133, but negative for CD44, appears after 7 days culture on hECM, a population which is reduced by 50 % in cells grown on heparan sulfated-depleted hECM. Collectively, the data suggest that hECM induces growth factors and receptors regulating proliferation of metastatic CRC in the liver and offers a growth advantage for specific populations expressing CSC markers.
    Clinical and Experimental Metastasis 08/2012; · 3.46 Impact Factor

Publication Stats

397 Citations
226.47 Total Impact Points

Institutions

  • 2008–2014
    • Tel Aviv University
      • • Faculty of Life Sciences
      • • Department of Human Molecular Genetics and Biochemistry
      • • Department of Cell Research and Immunology
      Tell Afif, Tel Aviv, Israel
  • 2012
    • Université René Descartes - Paris 5
      Lutetia Parisorum, Île-de-France, France