Brill-Karniely Y, Dror D, Duanis-Assaf T, Goldstein Y, Schwob O, Millo T, Orehov N, Stern T, Jaber M, Loyfer N, Vosk-Artzi M, Benyamini H, Bielenberg D, Kaplan T, Buganim Y, Reches M, Benny O. Triangular correlation (TrC) between cancer aggressiveness, cell uptake capability, and cell deformability [Internet]. Sci Adv 2020;6:eaax2861.Available from: https://pubmed.ncbi.nlm.nih.gov/31998832/ PubMedThe malignancy potential is correlated with the mechanical deformability of the cancer cells. However, mechanical tests for clinical applications are limited. We present here a Triangular Correlation (TrC) between cell deformability, phagocytic capacity, and cancer aggressiveness, suggesting that phagocytic measurements can be a mechanical surrogate marker of malignancy. The TrC was proved in human prostate cancer cells with different malignancy potential, and in human bladder cancer and melanoma cells that were sorted into subpopulations based solely on their phagocytic capacity. The more phagocytic subpopulations showed elevated aggressiveness ex vivo and in vivo. The uptake potential was preserved, and differences in gene expression and in epigenetic signature were detected. In all cases, enhanced phagocytic and aggressiveness phenotypes were correlated with greater cell deformability and predicted by a computational model. Our multidisciplinary study provides the proof of concept that phagocytic measurements can be applied for cancer diagnostics and precision medicine.
Kumar S, Sharife H, Kreisel T, Mogilevsky M, Bar-Lev L, Grunewald M, Aizenshtein E, Karni R, Paldor I, Shlomi T, Keshet E. Intra-Tumoral Metabolic Zonation and Resultant Phenotypic Diversification Are Dictated by Blood Vessel Proximity [Internet]. Cell Metab 2019;30:201-211 e6.Available from: https://pubmed.ncbi.nlm.nih.gov/31056286 PubMedDifferential exposure of tumor cells to blood-borne and angiocrine factors results in diverse metabolic microenvironments conducive for non-genetic tumor cell diversification. Here, we harnessed a methodology for retrospective sorting of fully functional, stroma-free cancer cells solely on the basis of their relative distance from blood vessels (BVs) to unveil the whole spectrum of genes, metabolites, and biological traits impacted by BV proximity. In both grafted mouse tumors and natural human glioblastoma (GBM), mTOR activity was confined to few cell layers from the nearest perfused vessel. Cancer cells within this perivascular tier are distinguished by intense anabolic metabolism and defy the Warburg principle through exercising extensive oxidative phosphorylation. Functional traits acquired by perivascular cancer cells, namely, enhanced tumorigenicity, superior migratory or invasive capabilities, and, unexpectedly, exceptional chemo- and radioresistance, are all mTOR dependent. Taken together, the study revealed a previously unappreciated graded metabolic zonation directly impacting the acquisition of multiple aggressive tumor traits.
Yanay N, Elbaz M, Konikov-Rozenman J, Elgavish S, Nevo Y, Fellig Y, Rabie M, Mitrani-Rosenbaum S, Nevo Y. Pax7, Pax3 and Mamstr genes are involved in skeletal muscle impaired regeneration of dy2J/dy2J mouse model of Lama2-CMD [Internet]. Hum Mol Genet 2019;28:3369-3390.Available from: https://pubmed.ncbi.nlm.nih.gov/31348492 PubMedCongenital muscular dystrophy type-1A (Lama2-CMD) and Duchenne muscular dystrophy (DMD) result from deficiencies of laminin-α2 and dystrophin proteins, respectively. Although both proteins strengthen the sarcolemma, they are implicated in clinically distinct phenotypes. We used RNA-deep sequencing (RNA-Seq) of dy2J/dy2J, Lama2-CMD mouse model, skeletal muscle at 8 weeks of age to elucidate disease pathophysiology. This study is the first report of dy2J/dy2J model whole transcriptome profile. RNA-Seq of the mdx mouse model of DMD and wild-type (WT) mouse was carried as well in order to enable a novel comparison of dy2J/dy2J to mdx. A large group of shared differentially expressed genes (DEGs) was found in dy2J/dy2J and mdx models (1834 common DEGs, false discovery rate [FDR] < 0.05). Enrichment pathway analysis using ingenuity pathway analysis showed enrichment of inflammation, fibrosis, cellular movement, migration and proliferation of cells, apoptosis and necrosis in both mouse models (P-values 3E-10-9E-37). Via canonical pathway analysis, actin cytoskeleton, integrin, integrin-linked kinase, NF-kB, renin-angiotensin, epithelial-mesenchymal transition, and calcium signaling were also enriched and upregulated in both models (FDR < 0.05). Interestingly, significant downregulation of Pax7 was detected in dy2J/dy2J compared to upregulation of this key regeneration gene in mdx mice. Pax3 and Mamstr genes were also downregulated in dy2J/dy2J compared to WT mice. These results may explain the distinct disease course and severity in these models. While the mdx model at that stage shows massive regeneration, the dy2J/dy2J shows progressive dystrophic process. Our data deepen our understanding of the molecular pathophysiology and suggest new targets for additional therapies to upregulate regeneration in Lama2-CMD.
Vinograd-Byk H, Renbaum P, Levy-Lahad E. Vrk1 partial Knockdown in Mice Results in Reduced Brain Weight and Mild Motor Dysfunction, and Indicates Neuronal VRK1 Target Pathways. Sci Rep 2018;8:11265.Mutations in Vaccinia-related kinase 1 (VRK1) have emerged as a cause of severe neuronal phenotypes in human, including brain developmental defects and degeneration of spinal motor neurons, leading to Spinal Muscular Atrophy (SMA) or early onset Amyotrophic Lateral Sclerosis (ALS). Vrk1 gene-trap partial Knockout (KO) mice (Vrk1(GT3/GT3)), which express decreased levels of Vrk1, are sterile due to impaired gamete production. Here, we examined whether this mouse model also presents neuronal phenotypes. We found a 20-50% reduction in Vrk1 expression in neuronal tissues of the Vrk1(GT3/GT3) mice, leading to mild neuronal phenotypes including significant but small reduction in brain mass and motor (rotarod) impairment. Analysis of gene expression in the Vrk1(GT3/GT3) cortex predicts novel roles for VRK1 in neuronal pathways including neurotrophin signaling, axon guidance and pathways implicated in the pathogenesis of ALS. Together, our studies of the partial KO Vrk1 mice reveal that even moderately reduced levels of Vrk1 expression result in minor neurological impairment and indicate new neuronal pathways likely involving VRK1.
Khare D, Or R, Resnick I, Barkatz C, Almogi-Hazan O, Avni B. Mesenchymal Stromal Cell-Derived Exosomes Affect mRNA Expression and Function of B-Lymphocytes. Front Immunol 2018;9:3053.Background: Bone marrow mesenchymal stem cells (bmMSC) may play a role in the regulation of maturation, proliferation, and functional activation of lymphocytes, though the exact mechanisms are unknown. MSC-derived exosomes induce a regulatory response in the function of B, T, and monocyte-derived dendritic cells. Here, we evaluated the specific inhibition of human lymphocytes by bmMSC-derived exosomes and the effects on B-cell function. Methods: Exosomes were isolated from culture media of bmMSC obtained from several healthy donors. The effect of purified bmMSC-derived exosomes on activated peripheral blood mononuclear cells (PBMCs) and isolated B and T lymphocyte proliferation was measured by carboxyfluorescein succinimidyl ester assay. Using the Illumina sequencing platform, mRNA profiling was performed on B-lymphocytes activated in the presence or absence of exosomes. Ingenuity(R) pathway analysis software was applied to analyze pathway networks, and biological functions of the differentially expressed genes. Validation by RT-PCR was performed. The effect of bmMSC-derived exosomes on antibody secretion was measured by ELISA. Results: Proliferation of activated PBMCs or isolated T and B cells co-cultured with MSC-derived exosomes decreased by 37, 23, and 18%, respectively, compared to controls. mRNA profiling of activated B-lymphocytes revealed 186 genes that were differentially expressed between exosome-treated and control cells. We observed down- and up-regulation of genes that are involved in cell trafficking, development, hemostasis, and immune cell function. RNA-Seq results were validated by real time PCR analysis for the expression of CXCL8 (IL8) and MZB1 genes that are known to have an important role in immune modulation. Functional alterations were confirmed by decreased IgM production levels. Consistent results were demonstrated among a wide variety of healthy human bmMSC donors. Conclusion: Our data show that exosomes may play an important role in immune regulation. They inhibit proliferation of several types of immune cells. In B-lymphocytes they modulate cell function by exerting differential expression of the mRNA of relevant genes. The results of this study help elucidate the mechanisms by which exosomes induce immune regulation and may contribute to the development of newer and safer therapeutic strategies.
Rimmerman N, Schottlender N, Reshef R, Dan-Goor N, Yirmiya R. The hippocampal transcriptomic signature of stress resilience in mice with microglial fractalkine receptor (CX3CR1) deficiency. Brain Behav Immun 2017;61:184-196.Clinical studies suggest that key genetic factors involved in stress resilience are related to the innate immune system. In the brain, this system includes microglia cells, which play a major role in stress responsiveness. Consistently, mice with deletion of the CX3CR1 gene (CX3CR1(-/-) mice), which in the brain is expressed exclusively by microglia, exhibit resilience to chronic stress. Here, we compared the emotional, cognitive, neurogenic and microglial responses to chronic unpredictable stress (CUS) between CX3CR1(-/-) and wild type (WT) mice. This was followed by hippocampal whole transcriptome (RNA-seq) analysis. We found that following CUS exposure, WT mice displayed reduced sucrose preference, impaired novel object recognition memory, and reduced neurogenesis, whereas CX3CR1(-/-) mice were completely resistant to these effects of CUS. CX3CR1(-/-) mice were also resilient to the memory-suppressive effect of a short period of unpredictable stress. Microglial somas were larger in CX3CR1(-/-) than in WT, but in both genotypes CUS induced a similar decline in hippocampal microglial density and processes length. RNA sequencing and pathway analysis revealed basal strain differences, particularly reduced expression of interferon (IFN)-regulated and MHC class I gene transcripts in CX3CR1(-/-) mice. Furthermore, while CUS exposure similarly altered neuronal gene transcripts (e.g. Arc, Npas4) in both strains, transcripts downstream of hippocampal estrogen receptor signaling (particularly Igf2 and Igfbp2) were altered only in CX3CR1(-/-) mice. These findings indicate that emotional and cognitive stress resilience involves CX3CR1-dependent basal and stress-induced alterations in hippocampal transcription, implicating inhibition of CX3CR1 signaling as a novel approach for promoting stress resilience.
Chai C, Rivkin M, Berkovits L, Simerzin A, Zorde-Khvalevsky E, Rosenberg N, Klein S, Yaish D, Durst R, Shpitzen S, Udi S, Tam J, Heeren J, Worthmann A, Schramm C, Kluwe J, Ravid R, Hornstein E, Giladi H, Galun E. Metabolic Circuit Involving Free Fatty Acids, microRNA 122, and Triglyceride Synthesis in Liver and Muscle Tissues. Gastroenterology 2017;153:1404-1415.BACKGROUND & AIMS: Effective treatments are needed for hepatic steatosis characterized by accumulation of triglycerides in hepatocytes, which leads to hepatocellular carcinoma. MicroRNA 122 (MIR122) is expressed only in the liver, where it regulates lipid metabolism. We investigated the mechanism by which free fatty acids (FFAs) regulate MIR122 expression and the effect of MIR122 on triglyceride synthesis. METHODS: We analyzed MIR122 promoter activity and validated its target mRNAs by transfection of Luciferase reporter plasmids into Huh7, BNL-1ME, and HEK293 cultured cell lines. We measured levels of microRNAs and mRNAs by quantitative real-time PCR analysis of RNA extracted from plasma, liver, muscle, and adipose tissues of C57BL/6 mice given the FFA-inducer CL316243. MIR122 was inhibited using an inhibitor of MIR122. Metabolic profiles of mice were determined using metabolic chambers and by histologic analyses of liver tissues. We performed RNA sequence analyses to identify metabolic pathways involving MIR122. RESULTS: We validated human Agpat1 and Dgat1 mRNAs, involved in triglyceride synthesis, as targets of MIR122. FFAs increased MIR122 expression in livers of mice by activating the retinoic acid-related orphan receptor alpha, and induced secretion of MIR122 from liver to blood. Circulating MIR122 entered muscle and adipose tissues of mice, reducing mRNA levels of genes involved in triglyceride synthesis. Mice injected with an inhibitor of MIR122 and then given CL316243, accumulated triglycerides in liver and muscle tissues, and had reduced rates of beta-oxidation. There was a positive correlation between level of FFAs and level of MIR122 in plasma samples from 6 healthy individuals, collected before and during fasting. CONCLUSIONS: In biochemical and histologic studies of plasma, liver, muscle, and adipose tissues from mice, we found that FFAs increase hepatic expression and secretion of MIR122, which regulates energy storage vs expenditure in liver and peripheral tissues. Strategies to reduce triglyceride levels, by increasing MIR122, might be developed for treatment of metabolic syndrome.
Weisblum Y, Oiknine-Djian E, Vorontsov OM, Haimov-Kochman R, Zakay-Rones Z, Meir K, Shveiky D, Elgavish S, Nevo Y, Roseman M, Bronstein M, Stockheim D, From I, Eisenberg I, Lewkowicz AA, Yagel S, Panet A, Wolf DG. Zika Virus Infects Early- and Midgestation Human Maternal Decidual Tissues, Inducing Distinct Innate Tissue Responses in the Maternal-Fetal Interface. J Virol 2017;91Zika virus (ZIKV) has emerged as a cause of congenital brain anomalies and a range of placenta-related abnormalities, highlighting the need to unveil the modes of maternal-fetal transmission. The most likely route of vertical ZIKV transmission is via the placenta. The earliest events of ZIKV transmission in the maternal decidua, representing the maternal uterine aspect of the chimeric placenta, have remained unexplored. Here, we show that ZIKV replicates in first-trimester human maternal-decidual tissues grown ex vivo as three-dimensional (3D) organ cultures. An efficient viral spread in the decidual tissues was demonstrated by the rapid upsurge and continued increase of tissue-associated ZIKV load and titers of infectious cell-free virus progeny, released from the infected tissues. Notably, maternal decidual tissues obtained at midgestation remained similarly susceptible to ZIKV, whereas fetus-derived chorionic villi demonstrated reduced ZIKV replication with increasing gestational age. A genome-wide transcriptome analysis revealed that ZIKV substantially upregulated the decidual tissue innate immune responses. Further comparison of the innate tissue response patterns following parallel infections with ZIKV and human cytomegalovirus (HCMV) revealed that unlike HCMV, ZIKV did not induce immune cell activation or trafficking responses in the maternal-fetal interface but rather upregulated placental apoptosis and cell death molecular functions. The data identify the maternal uterine aspect of the human placenta as a likely site of ZIKV transmission to the fetus and further reveal distinct patterns of innate tissue responses to ZIKV. Our unique experimental model and findings could further serve to study the initial stages of congenital ZIKV transmission and pathogenesis and evaluate the effect of new therapeutic interventions. IMPORTANCE: In view of the rapid spread of the current ZIKV epidemic and the severe manifestations of congenital ZIKV infection, it is crucial to learn the fundamental mechanisms of viral transmission from the mother to the fetus. Our studies of ZIKV infection in the authentic tissues of the human maternal-fetal interface unveil a route of transmission whereby virus originating from the mother could reach the fetal compartment via efficient replication within the maternal decidual aspect of the placenta, coinhabited by maternal and fetal cells. The identified distinct placental tissue innate immune responses and damage pathways could provide a mechanistic basis for some of the placental developmental abnormalities associated with ZIKV infection. The findings in the unique model of the human decidua should pave the way to future studies examining the interaction of ZIKV with decidual immune cells and to evaluation of therapeutic interventions aimed at the earliest stages of transmission.
Malakar P, Shilo A, Mogilevsky A, Stein I, Pikarsky E, Nevo Y, Benyamini H, Elgavish S, Zong X, Prasanth KV, Karni R. Long Noncoding RNA MALAT1 Promotes Hepatocellular Carcinoma Development by SRSF1 Upregulation and mTOR Activation. Cancer Res 2017;77:1155-1167.Several long noncoding RNAs (lncRNA) are abrogated in cancer but their precise contributions to oncogenesis are still emerging. Here we report that the lncRNA MALAT1 is upregulated in hepatocellular carcinoma and acts as a proto-oncogene through Wnt pathway activation and induction of the oncogenic splicing factor SRSF1. Induction of SRSF1 by MALAT1 modulates SRSF1 splicing targets, enhancing the production of antiapoptotic splicing isoforms and activating the mTOR pathway by modulating the alternative splicing of S6K1. Inhibition of SRSF1 expression or mTOR activity abolishes the oncogenic properties of MALAT1, suggesting that SRSF1 induction and mTOR activation are essential for MALAT1-induced transformation. Our results reveal a mechanism by which lncRNA MALAT1 acts as a proto-oncogene in hepatocellular carcinoma, modulating oncogenic alternative splicing through SRSF1 upregulation. Cancer Res; 77(5); 1155-67. ©2016 AACR.
Shahar T, Granit A, Zrihan D, Canello T, Charbit H, Einstein O, Rozovski U, Elgavish S, Ram Z, Siegal T, Lavon I. Expression level of miRNAs on chromosome 14q32.31 region correlates with tumor aggressiveness and survival of glioblastoma patients. J Neurooncol 2016;130:413-422.The 54 microRNAs (miRNAs) within the DLK-DIO3 genomic region on chromosome 14q32.31 (cluster-14-miRNAs) are organized into sub-clusters 14A and 14B. These miRNAs are downregulated in glioblastomas and might have a tumor suppressive role. Any association between the expression levels of cluster-14-miRNAs with overall survival (OS) is undetermined. We randomly selected miR-433, belonging to sub-cluster 14A and miR-323a-3p and miR-369-3p, belonging to sub-cluster 14B, and assessed their role in glioblastomas in vitro and in vivo. We also determined the expression level of cluster-14-miRNAs in 27 patients with newly diagnosed glioblastoma, and analyzed the association between their level of expression and OS. Overexpression of miR-323a-3p and miR-369-3p, but not miR-433, in glioblastoma cells inhibited their proliferation and migration in vitro. Mice implanted with glioblastoma cells overexpressing miR323a-3p and miR369-3p, but not miR433, exhibited prolonged survival compared to controls (P = .003). Bioinformatics analysis identified 13 putative target genes of cluster-14-miRNAs, and real-time RT-PCR validated these findings. Pathway analysis of the putative target genes identified neuregulin as the most enriched pathway. The expression level of cluster-14-miRNAs correlated with patients' OS. The median OS was 8.5 months for patients with low expression levels and 52.7 months for patients with high expression levels (HR 0.34; 95 % CI 0.12-0.59, P = .003). The expression level of cluster-14-miRNAs correlates directly with OS, suggesting a role for this cluster in promoting aggressive behavior of glioblastoma, possibly through ErBb/neuregulin signaling.
Guedj A, Geiger-Maor A, Galun E, Benyamini H, Nevo Y, Elgavish S, Amsalem H, Rachmilewitz J. Early age decline in DNA repair capacity in the liver: in depth profile of differential gene expression. Aging (Albany NY) 2016;8:3131-3146.Aging is associated with progressive decline in cell function and with increased damage to macromolecular components. DNA damage, in the form of double-strand breaks (DSBs), increases with age and in turn, contributes to the aging process and age-related diseases. DNA strand breaks triggers a set of highly orchestrated signaling events known as the DNA damage response (DDR), which coordinates DNA repair. However, whether the accumulation of DNA damage with age is a result of decreased repair capacity, remains to be determined. In our study we showed that with age there is a decline in the resolution of foci containing γH2AX and pKAP-1 in diethylnitrosamine (DEN)-treated mouse livers, already evident at a remarkably early age of 6-months. Considerable age-dependent differences in global gene expression profiles in mice livers after exposure to DEN, further affirmed these age related differences in the response to DNA damage. Functional analysis identified p53 as the most overrepresented pathway that is specifically enhanced and prolonged in 6-month-old mice. Collectively, our results demonstrated an early decline in DNA damage repair that precedes 'old age', suggesting this may be a driving force contributing to the aging process rather than a phenotypic consequence of old age.
Charbit H, Benis A, Geyshis B, Karussis D, Petrou P, Vaknin-Dembinsky A, Lavon I. Sex-specific prediction of interferon beta therapy response in relapsing-remitting multiple sclerosis. J Clin Neurosci 2015;22:986-9.Multiple sclerosis (MS) is a demyelinating disorder predominantly affecting young people. Currently, interferon beta (IFNbeta) is a common treatment for MS. Despite a large effort in recent years, valid biomarkers with predictive value for clinical outcome and response to therapy are lacking. In order to identify predictive biomarkers of response to IFNbeta therapy in relapsing-remitting MS patients, we analyzed expression of 526 immune-related genes with the nCounter Analysis System (NanoString Technologies, Seattle, WA, USA) on total RNA extracted from peripheral blood mononuclear cells of 30 relapsing-remitting MS patients. We used a Wilcoxon signed-rank test to find an association between certain gene expression profiles and clinical responses to IFNbeta. We compared the expression profile of patients who responded to IFNbeta treatment (n=16) and non-responsive IFNbeta patients (n=14). The analysis revealed that the expression of eight genes could differentiate between responsive and non-responsive men (p0.005). This differentiation was not evident in women. We analyzed results from an additional cohort of 47 treated and untreated patients to validate the results and explore whether this eight gene cluster could also predict treatment response. Analysis of the validation cohort demonstrated that three out of the eight genes remained significant in only the treated men (p0.05). Our findings could be used as a basis for establishing a routine test for objective prediction of IFNbeta treatment response in male MS patients.