Inversed relationship between CD44 variant and c-Myc due to oxidative stress-induced canonical Wnt activation

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Yoshida, Go J.; Saya, Hideyuki

2014-01-01

Highlights: •CD44 variant8–10 and c-Myc are inversely expressed in gastric cancer cells. •Redox-stress enhances c-Myc expression via canonical Wnt signal. •CD44v, but not CD44 standard, suppresses redox stress-induced Wnt activation. •CD44v expression promotes both transcription and proteasome degradation of c-Myc. •Inversed expression pattern between CD44v and c-Myc is often recognized in vivo. -- Abstract: Cancer stem-like cells express high amount of CD44 variant8-10 which protects cancer cells from redox stress. We have demonstrated by immunohistochemical analysis and Western blotting, and reverse-transcription polymerase chain reaction, that CD44 variant8-10 and c-Myc tend to show the inversed expression manner in gastric cancer cells. That is attributable to the oxidative stress-induced canonical Wnt activation, and furthermore, the up-regulation of the downstream molecules, one of which is oncogenic c-Myc, is not easily to occur in CD44 variant-positive cancer cells. We have also found out that CD44v8-10 expression is associated with the turn-over of the c-Myc with the experiments using gastric cancer cell lines. This cannot be simply explained by the model of oxidative stress-induced Wnt activation. CD44v8-10-positive cancer cells are enriched at the invasive front. Tumor tissue at the invasive area is considered to be composed of heterogeneous cellular population; dormant cancer stem-like cells with CD44v8-10 high / Fbw7 high / c-Myc low and proliferative cancer stem-like cells with CD44v8-10 high / Fbw7 low / c-Myc high

Inversed relationship between CD44 variant and c-Myc due to oxidative stress-induced canonical Wnt activation

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Yoshida, Go J., E-mail: medical21go@yahoo.co.jp; Saya, Hideyuki

2014-01-10

Highlights: •CD44 variant8–10 and c-Myc are inversely expressed in gastric cancer cells. •Redox-stress enhances c-Myc expression via canonical Wnt signal. •CD44v, but not CD44 standard, suppresses redox stress-induced Wnt activation. •CD44v expression promotes both transcription and proteasome degradation of c-Myc. •Inversed expression pattern between CD44v and c-Myc is often recognized in vivo. -- Abstract: Cancer stem-like cells express high amount of CD44 variant8-10 which protects cancer cells from redox stress. We have demonstrated by immunohistochemical analysis and Western blotting, and reverse-transcription polymerase chain reaction, that CD44 variant8-10 and c-Myc tend to show the inversed expression manner in gastric cancer cells. That is attributable to the oxidative stress-induced canonical Wnt activation, and furthermore, the up-regulation of the downstream molecules, one of which is oncogenic c-Myc, is not easily to occur in CD44 variant-positive cancer cells. We have also found out that CD44v8-10 expression is associated with the turn-over of the c-Myc with the experiments using gastric cancer cell lines. This cannot be simply explained by the model of oxidative stress-induced Wnt activation. CD44v8-10-positive cancer cells are enriched at the invasive front. Tumor tissue at the invasive area is considered to be composed of heterogeneous cellular population; dormant cancer stem-like cells with CD44v8-10 {sup high}/ Fbw7 {sup high}/ c-Myc {sup low} and proliferative cancer stem-like cells with CD44v8-10 {sup high}/ Fbw7 {sup low}/ c-Myc {sup high}.

HA/CD44 interactions as potential targets for cancer therapy

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Misra, Suniti; Heldin, Paraskevi; Hascall, Vincent C.; Karamanos, Nikos K.; Skandalis, Spyros S.; Markwald, Roger R.; Ghatak, Shibnath

2011-01-01

It is becoming increasingly clear that signals generated in tumor microenvironments are crucial to tumor cell behavior, such as, survival progression, and metastasis. The establishment of these malignant behaviors requires that tumor cells acquire novel adhesion and migration properties to detach from their original sites for localizing into distant organs. CD44, an adhesion/homing molecule is a major receptor for the glycosaminoglycan hyaluronan, which is one of the major components of the tumor extracellular matrix (ECM). CD44, a multi structural and multifunctional molecule, detects changes in ECM components, and thus is well positioned to provide appropriate responses to changes in the microenvironment, i.e. engagement in cell-cell and cell-ECM interactions, cell traffic, lymph node homing, and presentation of growth factors/cytokines/chemokines to co-ordinate signaling events that enable the cell responses that change in the tissue environment. The potential involvement of CD44variants (CD44v), especially CD44v4-v7 and CD44v6-v9 in tumor progression was confirmed for many tumor types in numerous clinical studies. Down regulation of the standard CD44 isoform (CD44s) in colon cancer is postulated to result in increased tumorigenicity. CD44v-specific functions could be due to their higher binding affinity for hyaluronan than CD44s. Alternatively, CD44v-specific functions could be due to differences in associating molecules, which may bind selectively to the CD44v exon. This review summarizes how the interaction between hyaluronan and CD44v can serve as a potential target for cancer therapy, in particular how silencing the CD44v can target multiple metastatic tumors. PMID:21362138

MET Signaling Mediates Intestinal Crypt-Villus Development, Regeneration, and Adenoma Formation and Is Promoted by Stem Cell CD44 Isoforms.

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Joosten, Sander P J; Zeilstra, Jurrit; van Andel, Harmen; Mijnals, R Clinton; Zaunbrecher, Joost; Duivenvoorden, Annet A M; van de Wetering, Marc; Clevers, Hans; Spaargaren, Marcel; Pals, Steven T

2017-10-01

Resistance of metastatic human colorectal cancer cells to drugs that block epidermal growth factor (EGF) receptor signaling could be caused by aberrant activity of other receptor tyrosine kinases, activating overlapping signaling pathways. One of these receptor tyrosine kinases could be MET, the receptor for hepatocyte growth factor (HGF). We investigated how MET signaling, and its interaction with CD44 (a putative MET coreceptor regulated by Wnt signaling and highly expressed by intestinal stem cells [ISCs] and adenomas) affects intestinal homeostasis, regeneration, and adenoma formation in mini-gut organoids and mice. We established organoid cultures from ISCs stimulated with HGF or EGF and assessed intestinal differentiation by immunohistochemistry. Mice with total epithelial disruption of MET (Ah Cre /Met fl/fl /LacZ) or ISC-specific disruption of MET (Lgr5 Creert2 /Met fl/fl /LacZ) and control mice (Ah Cre /Met +/+ /LacZ, Lgr5 Creert2 /Met +/+ /LacZ) were exposed to 10 Gy total body irradiation; intestinal tissues were collected, and homeostasis and regeneration were assessed by immunohistochemistry. We investigated adenoma organoid expansion stimulated by HGF or EGF using adenomas derived from Lgr5 Creert2 /Met fl/fl /Apc fl/fl and Lgr5 Creert2 /Met +/+ /Apc fl/fl mice. The same mice were evaluated for adenoma prevalence and size. We also quantified adenomas in Ah Cre /Met fl/fl /Apc fl/+ mice compared with Ah Cre /Met +/+ /Apc fl/+ control mice. We studied expansion of organoids generated from crypts and adenomas, stimulated by HGF or EGF, that were derived from mice expressing different CD44 splice variants (Cd44 +/+ , Cd44 -/- , Cd44 s/s , or Cd44 v4-10/v4-10 mice). Crypts incubated with EGF or HGF expanded into self-organizing mini-guts with similar levels of efficacy and contained all differentiated cell lineages. MET-deficient mice did not have defects in intestinal homeostasis. Total body irradiation reduced numbers of proliferating crypts in Ah Cre

Menstrual endometrial cells from women with endometriosis demonstrate increased adherence to peritoneal cells and increased expression of CD44 splice variants.

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Griffith, Jason S; Liu, Ya-Guang; Tekmal, Rajeshwar R; Binkley, Peter A; Holden, Alan E C; Schenken, Robert S

2010-04-01

We previously demonstrated that adherence of endometrial epithelial (EECs) and stromal cells (ESCs) to peritoneal mesothelial cells (PMCs) is partly regulated by ESC/EEC CD44 interactions with PMC associated hyaluronan. CD44, a transmembrane glycoprotein and major ligand for hyaluronan, has numerous splice variants which may impact hyaluronan binding. Here, we assessed whether ESCs and EECs from women with endometriosis demonstrate increased adherence to PMCs and examined CD44 splice variants' potential role in this process. In vitro study. Academic medical center. Fertility patients with and without endometriosis. Menstrual endometrium was collected from women with and without endometriosis confirmed surgically. The adherence of ESC/EECs to PMCs was measured. The ESC/EEC CD44 splice variants were assessed using dot-blot analysis. The ESCs and EECs from women with endometriosis demonstrated increased adherence to PMCs. The predominant CD44 splice variants expressed by ESCs and EECs from women with and without endometriosis were v3, v6, v7, v8, v9, and v10. The ESCs and EECs from women with endometriosis were more likely to express v6, v7, v8, and v9. Increased eutopic endometrial-PMC adherence and CD44 splice variant expression may contribute to the histogenesis of endometriotic lesions. Elucidation of factors controlling this expression may lead to novel endometriosis therapies. Copyright 2010 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

mRNA Quantification of NIPBL Isoforms A and B in Adult and Fetal Human Tissues, and a Potentially Pathological Variant Affecting Only Isoform A in Two Patients with Cornelia de Lange Syndrome

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Beatriz Puisac

2017-02-01

Full Text Available Cornelia de Lange syndrome (CdLS is a congenital developmental disorder characterized by craniofacial dysmorphia, growth retardation, limb malformations, and intellectual disability. Approximately 60% of patients with CdLS carry a recognizable pathological variant in the NIPBL gene, of which two isoforms, A and B, have been identified, and which only differ in the C-terminal segment. In this work, we describe the distribution pattern of the isoforms A and B mRNAs in tissues of adult and fetal origin, by qPCR (quantitative polymerase chain reaction. Our results show a higher gene expression of the isoform A, even though both seem to have the same tissue distribution. Interestingly, the expression in fetal tissues is higher than that of adults, especially in brain and skeletal muscle. Curiously, the study of fibroblasts of two siblings with a mild CdLS phenotype and a pathological variant specific of the isoform A of NIPBL (c.8387A > G; P.Tyr2796Cys, showed a similar reduction in both isoforms, and a normal sensitivity to DNA damage. Overall, these results suggest that the position of the pathological variant at the 3´ end of the NIPBL gene affecting only isoform A, is likely to be the cause of the atypical mild phenotype of the two brothers.

Chondroitin sulfate addition to CD44H negatively regulates hyaluronan binding

International Nuclear Information System (INIS)

Ruffell, Brian; Johnson, Pauline

2005-01-01

CD44 is a widely expressed cell adhesion molecule that binds hyaluronan, an extracellular matrix glycosaminoglycan, in a tightly regulated manner. This regulated interaction has been implicated in inflammation and tumor metastasis. CD44 exists in the standard form, CD44H, or as higher molecular mass isoforms due to alternative splicing. Here, we identify serine 180 in human CD44H as the site of chondroitin sulfate addition and show that lack of chondroitin sulfate addition at this site enhances hyaluronan binding by CD44. A CD44H-immunoglobulin fusion protein expressed in HEK293 cells, and CD44H expressed in murine L fibroblast cells were modified by chondroitin sulfate, as determined by reduced sulfate incorporation after chondroitinase ABC treatment. Mutation of serine 180 or glycine 181 in CD44H reduced chondroitin sulfate addition and increased hyaluronan binding, indicating that serine 180 is the site for chondroitin sulfate addition in CD44H and that this negatively regulates hyaluronan binding

Modulation of neuronal differentiation by CD40 isoforms

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Hou Huayu; Obregon, Demian; Lou, Deyan; Ehrhart, Jared; Fernandez, Frank; Silver, Archie; Tan Jun

2008-01-01

Neuron differentiation is a complex process involving various cell-cell interactions, and multiple signaling pathways. We showed previously that CD40 is expressed and functional on mouse and human neurons. In neurons, ligation of CD40 protects against serum withdrawal-induced injury and plays a role in survival and differentiation. CD40 deficient mice display neuron dysfunction, aberrant neuron morphologic changes, and associated gross brain abnormalities. Previous studies by Tone and colleagues suggested that five isoforms of CD40 exist with two predominant isoforms expressed in humans: signal-transducible CD40 type I and a C-terminal truncated, non-signal-transducible CD40 type II. We hypothesized that differential expression of CD40 isoform type I and type II in neurons may modulate neuron differentiation. Results show that adult wild-type, and CD40 -/- deficient mice predominantly express CD40 type I and II isoforms. Whereas adult wild-type mice express mostly CD40 type I in cerebral tissues at relatively high levels, in age and gender-matched CD40 -/- mice CD40 type I expression was almost completely absent; suggesting a predominance of the non-signal-transducible CD40 type II isoform. Younger, 1 day old wild-type mice displayed less CD40 type I, and more CD40 type II, as well as, greater expression of soluble CD40 (CD40L/CD40 signal inhibitor), compared with 1 month old mice. Neuron-like N2a cells express CD40 type I and type II isoforms while in an undifferentiated state, however once induced to differentiate, CD40 type I predominates. Further, differentiated N2a cells treated with CD40 ligand express high levels of neuron specific nuclear protein (NeuN); an effect reduced by anti-CD40 type I siRNA, but not by control (non-targeting) siRNA. Altogether these data suggest that CD40 isoforms may act in a temporal fashion to modulate neuron differentiation during brain development. Thus, modulation of neuronal CD40 isoforms and CD40 signaling may represent

CD44: molecular interactions, signalling and functions in the nervous system.

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Grzegorz Marek Wilczynski

2015-05-01

Full Text Available CD44 is the major surface hyaluronan receptor implicated in intercellular and cell-matrix adhesion, cell migration and signalling. It is a transmembrane, highly glycosylated protein with several isoforms resulting from alternative gene splicing. The CD44 molecule consists of several domains serving different functions: the N-terminal extracellular domain, the stem region, the transmembrane domain and the C-terminal tail. In the nervous system, CD44 expression occurs in both glial and neuronal cells. The role of CD44 in the physiology and pathology of the nervous system is not entirely understood, however, there exists evidence suggesting it might be involved in the axon guidance, cytoplasmic Ca2+ clearance, dendritic arborization, synaptic transmission, epileptogenesis, oligodendrocyte and astrocyte differentiation, post-traumatic brain repair and brain tumour development.

Regulation of proximal tubular epithelial cell CD44-mediated binding and internalisation of hyaluronan.

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Jones, Stuart George; Ito, Takafumi; Phillips, Aled Owain

2003-09-01

Increased expression of the connective tissue polysaccharide hyaluronan (HA) in the renal corticointerstitium is associated with progressive renal fibrosis. Numerous studies have demonstrated involvement proximal tubular epithelial cells in the fibrotic process and in the current study we have characterised their expression of the HA receptor, CD44, and examined changes in CD44 expression and function in response to either IL-1beta or glucose. Characterisation of CD44 splice variant expression was carried out in primary cultures of human proximal tubular cells (PTC) and HK2 cells. Binding and internalisation HA was examined by addition of exogenous of fluorescein-HA (fl-HA), and expression of CD44 examined by immunoblot analysis and flow cytometry. Alteration in "functional" CD44 was determined by immunoprecipitation of CD44 following stimulation in the presence of fl-HA. PTC, both primary culture and the PTC cell line, HK2, express at least 5 CD44 splice variants, the expression of which are not altered by addition of either IL-1beta or 25mM D-glucose. Addition of either stimulus increased cell surface binding and internalisation of fl-HA and increased expression of functionally active CD44. Increased binding and internalisation of fl-HA, was blocked by anti-CD44 antibody, and by the inhibition of O-glycosylation. The data demonstrate that stimuli inducing PTC HA synthesis also regulate PTC-HA interactions. Furthermore increased HA binding and internalisation is the result of post-translational modification of CD44 by O-glycosylation, rather than by alteration in expression of CD44 at the cell surface, or by alternate use of CD44 splice variants.

Downregulation of CD44 reduces doxorubicin resistance of CD44+CD24- breast cancer cells

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Phuc PV

2011-06-01

Full Text Available Pham Van Phuc, Phan Lu Chinh Nhan, Truong Hai Nhung, Nguyen Thanh Tam, Nguyen Minh Hoang, Vuong Gia Tue, Duong Thanh Thuy, Phan Kim NgocLaboratory of Stem Cell Research and Application, University of Science, Vietnam National University, Ho Chi Minh, VietnamBackground: Cells within breast cancer stem cell populations have been confirmed to have a CD44+CD24- phenotype. Strong expression of CD44 plays a critical role in numerous types of human cancers. CD44 is involved in cell differentiation, adhesion, and metastasis of cancer cells.Methods: In this study, we reduced CD44 expression in CD44+CD24- breast cancer stem cells and investigated their sensitivity to an antitumor drug. The CD44+CD24- breast cancer stem cells were isolated from breast tumors; CD44 expression was downregulated with siRNAs followed by treatment with different concentrations of the antitumor drug.Results: The proliferation of CD44 downregulated CD44+CD24- breast cancer stem cells was decreased after drug treatment. We noticed treated cells were more sensitive to doxorubicin, even at low doses, compared with the control groups.Conclusions: It would appear that expression of CD44 is integral among the CD44+CD24- cell population. Reducing the expression level of CD44, combined with doxorubicin treatment, yields promising results for eradicating breast cancer stem cells in vitro. This study opens a new direction in treating breast cancer through gene therapy in conjunction with chemotherapy.Keywords: antitumor drugs, breast cancer stem cells, CD44, CD44+CD24- cells, doxorubicin

Hyaluronate fragments reverse skin atrophy by a CD44-dependent mechanism.

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Gürkan Kaya

2006-12-01

Full Text Available BACKGROUND: Skin atrophy is a common manifestation of aging and is frequently accompanied by ulceration and delayed wound healing. With an increasingly aging patient population, management of skin atrophy is becoming a major challenge in the clinic, particularly in light of the fact that there are no effective therapeutic options at present. METHODS AND FINDINGS: Atrophic skin displays a decreased hyaluronate (HA content and expression of the major cell-surface hyaluronate receptor, CD44. In an effort to develop a therapeutic strategy for skin atrophy, we addressed the effect of topical administration of defined-size HA fragments (HAF on skin trophicity. Treatment of primary keratinocyte cultures with intermediate-size HAF (HAFi; 50,000-400,000 Da but not with small-size HAF (HAFs; 400,000 Da induced wild-type (wt but not CD44-deficient (CD44-/- keratinocyte proliferation. Topical application of HAFi caused marked epidermal hyperplasia in wt but not in CD44-/- mice, and significant skin thickening in patients with age- or corticosteroid-related skin atrophy. The effect of HAFi on keratinocyte proliferation was abrogated by antibodies against heparin-binding epidermal growth factor (HB-EGF and its receptor, erbB1, which form a complex with a particular isoform of CD44 (CD44v3, and by tissue inhibitor of metalloproteinase-3 (TIMP-3. CONCLUSIONS: Our observations provide a novel CD44-dependent mechanism for HA oligosaccharide-induced keratinocyte proliferation and suggest that topical HAFi application may provide an attractive therapeutic option in human skin atrophy.

Genetic Variants in CD44 and MAT1A Confer Susceptibility to Acute Skin Reaction in Breast Cancer Patients Undergoing Radiation Therapy

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Mumbrekar, Kamalesh Dattaram; Bola Sadashiva, Satish Rao [Department of Radiation Biology and Toxicology, School of Life Sciences, Manipal University, Manipal, Karnataka (India); Kabekkodu, Shama Prasada [Department of Biotechnology, School of Life Sciences, Manipal University, Manipal, Karnataka (India); Fernandes, Donald Jerard [Department of Radiotherapy and Oncology, Shirdi Saibaba Cancer Hospital and Research Centre, Kasturba Hospital, Manipal, Karnataka (India); Vadhiraja, Bejadi Manjunath [Department of Radiation Oncology, Manipal Hospital, Bengaluru, Karnataka (India); Suga, Tomo; Shoji, Yoshimi; Nakayama, Fumiaki; Imai, Takashi [Advanced Radiation Biology Research Program, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, Chiba (Japan); Satyamoorthy, Kapaettu, E-mail: ksatyamoorthy@yahoo.com [Department of Biotechnology, School of Life Sciences, Manipal University, Manipal, Karnataka (India)

2017-01-01

Purpose: Heterogeneity in radiation therapy (RT)-induced normal tissue toxicity is observed in 10% of cancer patients, limiting the therapeutic outcomes. In addition to treatment-related factors, normal tissue adverse reactions also manifest from genetic alterations in distinct pathways majorly involving DNA damage–repair genes, inflammatory cytokine genes, cell cycle regulation, and antioxidant response. Therefore, the common sequence variants in these radioresponsive genes might modify the severity of normal tissue toxicity, and the identification of the same could have clinical relevance as a predictive biomarker. Methods and Materials: The present study was conducted in a cohort of patients with breast cancer to evaluate the possible associations between genetic variants in radioresponsive genes described previously and the risk of developing RT-induced acute skin adverse reactions. We tested 22 genetic variants reported in 18 genes (ie, NFE2L2, OGG1, NEIL3, RAD17, PTTG1, REV3L, ALAD, CD44, RAD9A, TGFβR3, MAD2L2, MAP3K7, MAT1A, RPS6KB2, ZNF830, SH3GL1, BAX, and XRCC1) using TaqMan assay-based real-time polymerase chain reaction. At the end of RT, the severity of skin damage was scored, and the subjects were dichotomized as nonoverresponders (Radiation Therapy Oncology Group grade <2) and overresponders (Radiation Therapy Oncology Group grade ≥2) for analysis. Results: Of the 22 single nucleotide polymorphisms studied, the rs8193 polymorphism lying in the micro-RNA binding site of 3′-UTR of CD44 was significantly (P=.0270) associated with RT-induced adverse skin reactions. Generalized multifactor dimensionality reduction analysis showed significant (P=.0107) gene–gene interactions between MAT1A and CD44. Furthermore, an increase in the total number of risk alleles was associated with increasing occurrence of overresponses (P=.0302). Conclusions: The genetic polymorphisms in radioresponsive genes act as genetic modifiers of acute normal tissue toxicity

Can CD44 Be a Mediator of Cell Destruction? The Challenge of Type 1 Diabetes

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Assayag-Asherie, Nathalie; Sever, Dror; Bogdani, Marika; Johnson, Pamela; Weiss, Talya; Ginzberg, Ariel; Perles, Sharon; Weiss, Lola; Sebban, Lora Eshkar; Turley, Eva A.; Okon, Elimelech; Raz, Itamar; Naor, David

2015-01-01

CD44 is a multi-functional receptor with multiple of isoforms engaged in modulation of cell trafficking and transmission of apoptotic signals. We have previously shown that injection of anti-CD44 antibody into NOD mice induced resistance to type 1 diabetes (T1D). In this communication we describe our efforts to understand the mechanism underlying this effect. We found that CD44-deficient NOD mice develop stronger resistance to T1D than wild-type littermates. This effect is not explained by the involvement of CD44 in cell migration, because CD44-deficient inflammatory cells surprisingly had greater invasive potential than the corresponding wild type cells, probably owing to molecular redundancy. We have previously reported and we show here again that CD44 expression and hyaluronic acid (HA, the principal ligand for CD44) accumulation are detected in pancreatic islets of diabetic NOD mice, but not of non-diabetic DBA/1 mice. Expression of CD44 on insulin-secreting β cells renders them susceptible to the autoimmune attack, and is associated with a diminution in β-cells function (e.g., less insulin production and/or insulin secretion) and possibly also with an enhanced apoptosis rate. The diabetes-supportive effect of CD44 expression on β cells was assessed by the TUNEL assay and further strengthened by functional assays exhibiting increased nitric oxide release, reduced insulin secretion after glucose stimulation and decreased insulin content in β cells. All these parameters could not be detected in CD44-deficient islets. We further suggest that HA-binding to CD44-expressing β cells is implicated in β-cell demise. Altogether, these data agree with the concept that CD44 is a receptor capable of modulating cell fate. This finding is important for other pathologies (e.g., cancer, neurodegenerative diseases) in which CD44 and HA appear to be implicated. PMID:26624007

Can CD44 Be a Mediator of Cell Destruction? The Challenge of Type 1 Diabetes.

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Nathalie Assayag-Asherie

Full Text Available CD44 is a multi-functional receptor with multiple of isoforms engaged in modulation of cell trafficking and transmission of apoptotic signals. We have previously shown that injection of anti-CD44 antibody into NOD mice induced resistance to type 1 diabetes (T1D. In this communication we describe our efforts to understand the mechanism underlying this effect. We found that CD44-deficient NOD mice develop stronger resistance to T1D than wild-type littermates. This effect is not explained by the involvement of CD44 in cell migration, because CD44-deficient inflammatory cells surprisingly had greater invasive potential than the corresponding wild type cells, probably owing to molecular redundancy. We have previously reported and we show here again that CD44 expression and hyaluronic acid (HA, the principal ligand for CD44 accumulation are detected in pancreatic islets of diabetic NOD mice, but not of non-diabetic DBA/1 mice. Expression of CD44 on insulin-secreting β cells renders them susceptible to the autoimmune attack, and is associated with a diminution in β-cells function (e.g., less insulin production and/or insulin secretion and possibly also with an enhanced apoptosis rate. The diabetes-supportive effect of CD44 expression on β cells was assessed by the TUNEL assay and further strengthened by functional assays exhibiting increased nitric oxide release, reduced insulin secretion after glucose stimulation and decreased insulin content in β cells. All these parameters could not be detected in CD44-deficient islets. We further suggest that HA-binding to CD44-expressing β cells is implicated in β-cell demise. Altogether, these data agree with the concept that CD44 is a receptor capable of modulating cell fate. This finding is important for other pathologies (e.g., cancer, neurodegenerative diseases in which CD44 and HA appear to be implicated.

Immunohistochemical expression of CD44s in renal cell carcinoma lacks independent prognostic significance

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Walter Henriques da Costa

2012-08-01

Full Text Available PURPOSE: To analyze the immunohistochemical expression of the standard isoform of CD44 (CD44s adhesion molecule in clear cell renal cell carcinoma (CCRCC and its impact on clinical outcomes. MATERIALS AND METHODS: Ninety-nine consecutive patients treated surgically for RCC between 1992 and 2009 were selected. A single pathologist reviewed all cases to effect a uniform reclassification and determine the most representative tumor areas for construction of a tissue microarray. The same pathologist, who was blinded to the outcome of the cases, semi-quantitatively scored the staining intensity of CD44s in all specimens. The counting was done using the H-Score algorithm. RESULTS: Of the 99 immunostained RCC specimens, 57(57.7% showed low expression, and 42(42.4% showed high expression levels of CD44s. The expression of CD44s was directly associated with tumor size (p = 0.03, clinical stage (p = 0.02 and Fuhrman grade (p = 0.02. Disease specific survival (DSS rates for patients whose specimens expressed low and high levels of CD44s was 88.1% and 67.5%, respectively (p = 0.009. Progression free survival (PFS rates in patients with low and high expression of CD44s were 78.8% and 61.7%, respectively (p = 0.05. Classical features such as the presence of metastasis and clinical stage remained isolated predictors of survival. CONCLUSIONS: Immunohistochemical expression of CD44s was associated with important clinical variables such as stage and Fuhrman grade. However, it was not an independent predictor of survival. Therefore, we believe it has a limited role as a prognostic marker in patients with CCRCC.

The Expression and Regulation of the Cell Adhesion Molecule CD44 in Human Breast Cancer

National Research Council Canada - National Science Library

Ge, Lisheng

1997-01-01

... alternative splicing signals of CD44 variant exons as control elements in CEPT. In our colon cancer metastasis to liver model, we developed dual modulation vectors to increase tissue-specific expression of cytosine deaminase (CD...

Expression of CD150 in tumors of the central nervous system: identification of a novel isoform.

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Olga Romanets-Korbut

Full Text Available CD150 (IPO3/SLAM belongs to the SLAM family of receptors and serves as a major entry receptor for measles virus. CD150 is expressed on normal and malignant cells of the immune system. However, little is known about its expression outside the hematopoietic system, especially tumors of the central nervous system (CNS. Although CD150 was not found in different regions of normal brain tissues, our immunohistochemical study revealed its expression in 77.6% of human CNS tumors, including glioblastoma, anaplastic astrocytoma, diffuse astrocytoma, ependymoma, and others. CD150 was detected in the cytoplasm, but not on the cell surface of glioma cell lines, and it was colocalized with the endoplasmic reticulum and Golgi complex markers. In addition to the full length mRNA of the mCD150 splice isoform, in glioma cells we found a highly expressed novel CD150 transcript (nCD150, containing an 83 bp insert. The insert is derived from a previously unrecognized exon designated Cyt-new, which is located 510 bp downstream of the transmembrane region exon, and is a specific feature of primate SLAMF1. Both mCD150 and nCD150 cDNA variants did not contain any mutations and had the leader sequence. The nCD150 transcript was also detected in normal and malignant B lymphocytes, primary T cells, dendritic cells and macrophages; however, in glioma cells nCD150 was found to be the predominant CD150 isoform. Similarly to mCD150, cell surface expression of nCD150 allows wild type measles virus entry to the cell. Our data indicate that CD150 expression in CNS tumors can be considered a new diagnostic marker and potential target for novel therapeutic approaches.

Heterogeneity of serum gelatinases MMP-2 and MMP-9 isoforms and charge variants

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Rossano, Rocco; Larocca, Marilena; Riviello, Lea; Coniglio, Maria Gabriella; Vandooren, Jennifer; Liuzzi, Grazia Maria; Opdenakker, Ghislain; Riccio, Paolo

2014-01-01

The matrix metalloproteinases (MMPs) gelatinase A (MMP-2) and gelatinase B (MMP-9) are mediators of brain injury in multiple sclerosis (MS) and valuable biomarkers of disease activity. We applied bidimensional zymography (2-DZ) as an extension of classic monodimensional zymography (1-DZ) to analyse the complete pattern of isoforms and post-translational modifications of both MMP-9 and MMP-2 present in the sera of MS patients. The enzymes were separated on the basis of their isoelectric points (pI) and apparent molecular weights (Mw) and identified both by comparison with standard enzyme preparations and by Western blot analysis. Two MMP-2 isoforms, and at least three different isoforms and two different states of organization of MMP-9 (the multimeric MMP-9 and the N-GAL-MMP-9 complex) were observed. In addition, 2-DZ revealed for the first time that all MMP-9 and MMP-2 isoforms actually exist in the form of charge variants: four or five variants in the N-GAL complex, more charge variants in the case of MMP-9; and five to seven charge variants for MMP-2. Charge variants were also observed in recombinant enzymes and, after concentration, also in sera from healthy individuals. Sialylation (MMP-9) and phosphorylation (MMP-2) contributed to molecular heterogeneity. The detection of charge variants of MMP-9 and MMP-2 in MS serum samples illustrates the power of 2-DZ and demonstrates that in previous studies MMP mixtures, rather than single molecules, were analysed. These observations open perspectives for better diagnosis and prognosis of many diseases and need to be critically interpreted when applying other methods for MS and other diseases. PMID:24616914

The human CD8β M-4 isoform dominant in effector memory T cells has distinct cytoplasmic motifs that confer unique properties.

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Deepshi Thakral

Full Text Available The CD8 co-receptor influences T cell recognition and responses in both anti-tumor and anti-viral immunity. During evolution in the ancestor of humans and chimpanzees, the CD8B gene acquired two additional exons. As a result, in humans, there are four CD8β splice variants (M1 to M4 that differ in their cytoplasmic tails. The M-1 isoform which is the equivalent of murine CD8β, is predominantly expressed in naïve T cells, whereas, the M-4 isoform is predominantly expressed in effector memory T cells. The characteristics of the M-4 isoform conferred by its unique 36 amino acid cytoplasmic tail are not known. In this study, we identified a dihydrophobic leucine-based receptor internalization motif in the cytoplasmic tail of M-4 that regulated its cell surface expression and downregulation after activation. Further the M-4 cytoplasmic tail was able to associate with ubiquitinated targets in 293T cells and mutations in the amino acids NPW, a potential EH domain binding site, either enhanced or inhibited the interaction. In addition, the M-4 tail was itself mono-ubiquitinated on a lysine residue in both 293T cells and a human T cell line. When peripheral blood human T cells expressed CD8αβ M-4, the frequency of MIP-1β secreting cells responding to antigen presenting cells was two-fold higher as compared to CD8αβ M-1 expressing T cells. Thus, the cytoplasmic tail of the CD8β M-4 isoform has unique characteristics, which likely contributed to its selective expression and function in human effector memory T cells.

Advances and advantages of nanomedicine in the pharmacological targeting of hyaluronan-CD44 interactions and signaling in cancer.

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Skandalis, Spyros S; Gialeli, Chrisostomi; Theocharis, Achilleas D; Karamanos, Nikos K

2014-01-01

Extensive experimental evidence in cell and animal tumor models show that hyaluronan-CD44 interactions are crucial in both malignancy and resistance to cancer therapy. Because of the intimate relationship between the hyaluronan-CD44 system and tumor cell survival and growth, it is an increasingly investigated area for applications to anticancer chemotherapeutics. Interference with the hyaluronan-CD44 interaction by targeting drugs to CD44, targeting drugs to the hyaluronan matrix, or interfering with hyaluronan matrix/tumor cell-associated CD44 interactions is a viable strategy for cancer treatment. Many of these methods can decrease tumor burden in animal models but have yet to show significant clinical utility. Recent advances in nanomedicine have offered new valuable tools for cancer detection, prevention, and treatment. The enhanced permeability and retention effect has served as key rationale for using nanoparticles to treat solid tumors. However, the targeted and uniform delivery of these particles to all regions of tumors in sufficient quantities requires optimization. An ideal nanocarrier should be equipped with selective ligands that are highly or exclusively expressed on target cells and thus endow the carriers with specific targeting capabilities. In this review, we describe how the hyaluronan-CD44 system may provide such an alternative in tumors expressing specific CD44 variants. © 2014 Elsevier Inc. All rights reserved.

Effect of curcumin on the cell surface markers CD44 and CD24 in breast cancer.

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Calaf, Gloria M; Ponce-Cusi, Richard; Abarca-Quinones, Jorge

2018-04-20

Human breast cell lines are often characterized based on the expression of the cell surface markers CD44 and CD24. CD44 is a type I transmembrane glycoprotein that regulates cell adhesion and cell-cell, as well as cell-extracellular matrix interactions. CD24 is expressed in benign and malignant solid tumors and is also involved in cell adhesion and metastasis. The aim of the present study was to investigate the effects of curcumin on the surface expression of CD44 and CD24 in breast epithelial cell lines. An established breast cancer model derived from the MCF-10F cell line was used. The results revealed that curcumin decreased CD44 and CD24 gene and protein expression levels in MCF-10F (normal), Alpha5 (premalignant) and Tumor2 (malignant) cell lines compared with the levels in their counterpart control cells. Flow cytometry revealed that the CD44+/CD24+ cell subpopulation was greater than the CD44+/CD24- subpopulation in these three cell lines. Curcumin increased CD44+/CD24+ to a greater extent and decreased CD44+/CD24- subpopulations in the normal MCF-10F and the pre-tumorigenic Alpha5 cells, but had no significant effect on Tumor2 cells compared with the corresponding control cells. Conversely, curcumin increased CD44 and decreased CD24 gene expression in MCF-7 breast cancer cells, and decreased CD44 gene expression in MDA-MB-231 cell line, while CD24 was not present in these cells. Curcumin did not alter the CD44+/CD24+ or CD44+/CD24- subpopulations in the MCF-7 cell line. However, it increased CD44+/CD24+ and decreased CD44+/CD24- subpopulations in MDA-MB-231 cells. In breast cancer specimens from patients, normal tissues were negative for CD44 and CD24 expression, while benign lesions were positive for both markers, and malignant tissues were found to be negative for CD44 and positive for CD24 in most cases. In conclusion, these results indicated that curcumin may be used to improve the proportion of CD44+/CD24+ cells and decrease the proportion of CD44

Evaluation of Stem Cell Markers, CD44/CD24 in Breast Cancer Cell Lines

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Masoud Hashemi Arabi

2014-05-01

Four breast cancer cell lines, MCF-7 ، T47D ، MDA-MB231 and MDA-MB468 were purchased from National cell Bank of Iran based in Iran Pasture Institute and were cultured in high glucose DMEM supplemented with 10% FCS. Cells were stained with antiCD44-PE and antiCD24-FITC antibodies and Status of CD44 and CD24 as markers of breast cancer stem cells were evaluated using flow cytometer and fluorescent microscopy.Evaluation of CD44 and CD24 as markers of breast cancer stem cells showed that MDA-MB231 with 97±1.2% CD44+/CD24-/low cells is significantly different from the others that they were mainly CD44 and CD24 positive cells(p

Preparation and bioevaluation of {sup 177}Lu-labelled anti-CD44 for radioimmunotherapy of colon cancer

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Lee, So Young; Hong, Young Don; Jung, Sung Hee; Choi, Sun Ju [Radioisotope Research Division, Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2015-12-15

CD44 is a particular adhesion molecule and facilitates both cell-cell and cell-matrix interactions. In particular, splice variants of CD44 are particularly overexpressed in a large number of malignancies and carcinomas. In this study, the {sup 177}Lu-labelled CD44 targeting antibody was prepared and bioevaluated in vitro and in vivo. Anti-CD44 was immunoconjugated with the equivalent molar ratio of cysteine-based dtPA-ncS and radioimmunoconjugated with {sup 177}Lu at room temperature within 15 minutes. the stability was tested in human serum. An in vitro study was carried out in Ht-29 human colon cancer cell lines. For the biodistribution study {sup 177}Lu-labelled anti-CD44 was injected in xenograft mice. Anti-CD44 was immunoconjugated with cysteinebased dtPA-ncS and purified by a centricon filter system having a molecular cut-off of 50 kda. radioimmunoconjugation with {sup 177}Lu was reacted for 15 min at room temperature. the radiolabeling yield was >99%, and it was stable in human serum without any fragmentation or degradation. The radioimmunoconjugate showed a high binding affinity on HT-29 colon cancer cell surfaces. In a biodistribution study, the tumor-to-blood ratio of the radioimmunoconjugate was 43 : 1 at 1 day post injection (p.i) in human colon cancer bearing mice. the anti-CD44 monoclonal antibody for the targeting of colon cancer was effectively radioimmunoconjugated with {sup 177}Lu. the in vitro high immunoactivity of this radioimmunoconjugate was determined by a cell binding assay. In addition, the antibody's tumor targeting ability was demonstrated with very high uptake in tumors. this radioimmunoconjugate is applicable to therapy in human colon cancer with highly expressed CD44.

In situ identification of CD44+/CD24- cancer cells in primary human breast carcinomas.

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Giuseppe Perrone

Full Text Available Breast cancer cells with the CD44+/CD24- phenotype have been reported to be tumourigenic due to their enhanced capacity for cancer development and their self-renewal potential. The identification of human tumourigenic breast cancer cells in surgical samples has recently received increased attention due to the implications for prognosis and treatment, although limitations exist in the interpretation of these studies. To better identify the CD44+/CD24- cells in routine surgical specimens, 56 primary breast carcinoma cases were analysed by immunofluorescence and confocal microscopy, and the results were compared using flow cytometry analysis to correlate the amount and distribution of the CD44+/CD24- population with clinicopathological features. Using these methods, we showed that the breast carcinoma cells displayed four distinct sub-populations based on the expression pattern of CD44 and CD24. The CD44+/CD24- cells were found in 91% of breast tumours and constituted an average of 6.12% (range, 0.11%-21.23% of the tumour. A strong correlation was found between the percentage of CD44+/CD24- cells in primary tumours and distant metastasis development (p = 0.0001; in addition, there was an inverse significant association with ER and PGR status (p = 0.002 and p = 0.001, respectively. No relationship was evident with tumour size (T and regional lymph node (N status, differentiation grade, proliferative index or HER2 status. In a multivariate analysis, the percentage of CD44+/CD24- cancer cells was an independent factor related to metastasis development (p = 0.004. Our results indicate that confocal analysis of fluorescence-labelled breast cancer samples obtained at surgery is a reliable method to identify the CD44+/CD24- tumourigenic cell population, allowing for the stratification of breast cancer patients into two groups with substantially different relapse rates on the basis of CD44+/CD24- cell percentage.

eCD4-Ig variants that more potently neutralize HIV-1.

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Fetzer, Ina; Gardner, Matthew R; Davis-Gardner, Meredith E; Prasad, Neha R; Alfant, Barnett; Weber, Jesse A; Farzan, Michael

2018-03-28

The HIV-1 entry inhibitor eCD4-Ig is a fusion of CD4-Ig and a coreceptor-mimetic peptide. eCD4-Ig is markedly more potent than CD4-Ig, with neutralization efficiencies approaching those of HIV-1 broadly neutralizing antibodies (bNAbs). However, unlike bNAbs, eCD4-Ig neutralizes all HIV-1, HIV-2 and SIV isolates that it has been tested against, suggesting that it may be useful in clinical settings where antibody escape is a concern. Here we characterize three new eCD4-Ig variants, each with different architectures and each utilizing D1.22, a stabilized form of CD4 domain 1. These variants were 10- to 20-fold more potent than our original eCD4-Ig variant, with a construct bearing four D1.22 domains (eD1.22-HL-Ig) exhibiting the greatest potency. However, this variant mediated less efficient antibody-dependent cell-mediated cytotoxicity (ADCC) activity than eCD4-Ig itself or several other eCD4-Ig variants, including the smallest variant (eD1.22-Ig). A variant with the same architecture as original eCD4-Ig (eD1.22-D2-Ig) showed modestly higher thermal stability and best prevented promotion of infection of CCR5-positive, CD4-negative cells. All three variants, and eCD4-Ig itself, mediated more efficient shedding of the HIV-1 envelope glycoprotein gp120 than did CD4-Ig. Finally, we show that only three D1.22 mutations contributed to the potency of eD1.22-D2-Ig, and that introduction of these changes into eCD4-Ig resulted in a variant 9-fold more potent than eCD4-Ig and 2-fold more potent than eD1.22-D2-Ig. These studies will assist in developing eCD4-Ig variants with properties optimized for prophylaxis, therapy, and cure applications. IMPORTANCE HIV-1 bNAbs have properties different from antiretroviral compounds. Specifically, antibodies can enlist immune effector cells to eliminate infected cells, whereas antiretroviral compounds simply interfere with various steps in the viral lifecycle. Unfortunately, HIV-1 is adept at evading antibody recognition, limiting the

CD44 is involved in mineralization of dental pulp cells.

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Chen, Kuan-Liang; Huang, Yu-Yuan; Lung, Jrhau; Yeh, Ying-Yi; Yuan, Kuo

2013-03-01

CD44 is a transmembrane glycoprotein with various biological functions. Histologic studies have shown that CD44 is strongly expressed in odontoblasts at the appositional stage of tooth development. We investigated whether CD44 is involved in the mineralization of dental pulp cells. Ten human third molars with incomplete root formation were collected and processed for immunohistochemistry of CD44. Dental pulp cells isolated from another 5 human third molars were assayed for their viability, alkaline phosphatase activity, and alizarin red staining in vitro after silencing stably their expression of CD44 by using the short hairpin RNA technique. The CD44 knockdown cells were cultured on a collagen sponge and transplanted subcutaneously into the dorsal surfaces of immunocompromised mice. After 6 weeks, the subcutaneous tissues were processed for alizarin red staining and immunohistochemistry of human specific antigen. The dental pulp cells transduced with control short hairpin RNA were used as the control in all assays. CD44 is expressed in odontogenic cells with active mineral deposition during tooth development. Odontoblasts in the root ends of immature teeth express a stronger CD44 signal compared with those in the crown portion. When CD44 expression was stably suppressed in dental pulp cells, their mineralization activities were substantially decreased in both in vitro and in vivo assays. CD44 may play a crucial role in the initial mineralization of tooth-associated structures. However, further studies are required to clarify the underlying mechanisms. Copyright © 2013 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

A novel KCNQ1 nonsense variant in the isoform-specific first exon causes both jervell and Lange-Nielsen syndrome 1 and long QT syndrome 1: a case report.

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Nishimura, Motoi; Ueda, Marehiko; Ebata, Ryota; Utsuno, Emi; Ishii, Takuma; Matsushita, Kazuyuki; Ohara, Osamu; Shimojo, Naoki; Kobayashi, Yoshio; Nomura, Fumio

2017-06-08

According to previous KCNQ1 (potassium channel, voltage gated, KQT-like subfamily, member 1) gene screening studies, missense variants, but not nonsense or frame-shift variants, cause the majority of long QT syndrome (LQTS; Romano-Ward syndrome [RWS]) 1 cases. Several missense variants are reported to cause RWS by a dominant-negative mechanism, and some KCNQ1 variants can cause both Jervell and Lange-Nielsen Syndrome (JLNS; in an autosomal recessive manner) and LQTS1 (in an autosomal dominant manner), while other KCNQ1 variants cause only JLNS. The human KCNQ1 gene is known to have two transcript isoforms (kidney isoform and pancreas isoform), and both isoforms can form a functional cardiac potassium channel. Here, we report a novel nonsense KCNQ1 variant causing not only JLNS, but also significant QTc prolongation identical to RWS in an autosomal dominant manner. Our case study supports that haploinsufficiency in the KCNQ1 gene is causative of significant QTc prolongation identical to RWS. Interestingly, the nonsense variant (NM_000218.2:c.115G > T [p.Glu39X]) locates in exon 1a of KCNQ1, which is a kidney-isoform specific exon. The variant is located closer to the N-terminus than previously identified nonsense or frame-shift variants. To the best of our knowledge, this is the first report showing that a nonsense variant in exon 1a of KCNQ1, which is the kidney-isoform specific exon, causes JLNS. Our findings may be informative to the genetic pathogenesis of RWS and JLNS caused by KCNQ1 variants.

The Invasion and Metastasis Promotion Role of CD97 Small Isoform in Gastric Carcinoma

DEFF Research Database (Denmark)

Liu, Daren; Trojanowicz, Bogusz; Ye, Longyun

2012-01-01

CD97 is over-expressed in the majority of gastric adenocarcinomas and is associated with its dedifferentiation and aggressiveness. Our previous results demonstrated that out of three CD97 isoforms tested, only the small one was able to promote increased invasiveness in vitro. Based on these data ...

Epigenetic regulation of CD44 in Hodgkin and non-Hodgkin lymphoma

International Nuclear Information System (INIS)

Eberth, Sonja; Schneider, Björn; Rosenwald, Andreas; Hartmann, Elena M; Romani, Julia; Zaborski, Margarete; Siebert, Reiner; Drexler, Hans G; Quentmeier, Hilmar

2010-01-01

Epigenetic inactivation of tumor suppressor genes (TSG) by promoter CpG island hypermethylation is a hallmark of cancer. To assay its extent in human lymphoma, methylation of 24 TSG was analyzed in lymphoma-derived cell lines as well as in patient samples. We screened for TSG methylation using methylation-specific multiplex ligation-dependent probe amplification (MS-MLPA) in 40 lymphoma-derived cell lines representing anaplastic large cell lymphoma, Burkitt lymphoma (BL), diffuse large B-cell lymphoma (DLBCL), follicular lymphoma (FL), Hodgkin lymphoma and mantle cell lymphoma (MCL) as well as in 50 primary lymphoma samples. The methylation status of differentially methylated CD44 was verified by methylation-specific PCR and bisulfite sequencing. Gene expression of CD44 and its reactivation by DNA demethylation was determined by quantitative real-time PCR and on the protein level by flow cytometry. Induction of apoptosis by anti-CD44 antibody was analyzed by annexin-V/PI staining and flow cytometry. On average 8 ± 2.8 of 24 TSG were methylated per lymphoma cell line and 2.4 ± 2 of 24 TSG in primary lymphomas, whereas 0/24 TSG were methylated in tonsils and blood mononuclear cells from healthy donors. Notably, we identified that CD44 was hypermethylated and transcriptionally silenced in all BL and most FL and DLBCL cell lines, but was usually unmethylated and expressed in MCL cell lines. Concordant results were obtained from primary lymphoma material: CD44 was not methylated in MCL patients (0/11) whereas CD44 was frequently hypermethylated in BL patients (18/29). In cell lines with CD44 hypermethylation, expression was re-inducible at mRNA and protein levels by treatment with the DNA demethylating agent 5-Aza-2'-deoxycytidine, confirming epigenetic regulation of CD44. CD44 ligation assays with a monoclonal anti-CD44 antibody showed that CD44 can mediate apoptosis in CD44 + lymphoma cells. CD44 hypermethylated, CD44 - lymphoma cell lines were consistently

CD44 Promotes intoxication by the clostridial iota-family toxins.

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Wigelsworth, Darran J; Ruthel, Gordon; Schnell, Leonie; Herrlich, Peter; Blonder, Josip; Veenstra, Timothy D; Carman, Robert J; Wilkins, Tracy D; Van Nhieu, Guy Tran; Pauillac, Serge; Gibert, Maryse; Sauvonnet, Nathalie; Stiles, Bradley G; Popoff, Michel R; Barth, Holger

2012-01-01

Various pathogenic clostridia produce binary protein toxins associated with enteric diseases of humans and animals. Separate binding/translocation (B) components bind to a protein receptor on the cell surface, assemble with enzymatic (A) component(s), and mediate endocytosis of the toxin complex. Ultimately there is translocation of A component(s) from acidified endosomes into the cytosol, leading to destruction of the actin cytoskeleton. Our results revealed that CD44, a multifunctional surface protein of mammalian cells, facilitates intoxication by the iota family of clostridial binary toxins. Specific antibody against CD44 inhibited cytotoxicity of the prototypical Clostridium perfringens iota toxin. Versus CD44(+) melanoma cells, those lacking CD44 bound less toxin and were dose-dependently resistant to C. perfringens iota, as well as Clostridium difficile and Clostridium spiroforme iota-like, toxins. Purified CD44 specifically interacted in vitro with iota and iota-like, but not related Clostridium botulinum C2, toxins. Furthermore, CD44 knockout mice were resistant to iota toxin lethality. Collective data reveal an important role for CD44 during intoxication by a family of clostridial binary toxins.

The role of a new CD44st in increasing the invasion capability of the human breast cancer cell line MCF-7

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Fang, Xin Jian; Jiang, Hua; Zhao, Xv Peng; Jiang, Wei Mei

2011-01-01

CD44, a hyaluronan (HA) receptor, is a multistructural and multifunctional cell surface molecule involved in cell proliferation, cell differentiation, cell migration, angiogenesis, presentation of cytokines, chemokines and growth factors to the corresponding receptors, and docking of proteases at the cell membrane, as well as in signaling for cell survival. The CD44 gene contains 20 exons that are alternatively spliced, giving rise to many CD44 isoforms, perhaps including tumor-specific sequences. Reverse transcriptase polymerase chain reaction (RT-PCR) and Western blotting were used to detect CD44st mRNA and CD44 protein in sensitive MCF-7, Lovo, K562 and HL-60 cell lines as well as their parental counterparts, respectively. The full length cDNA encoding CD44st was obtained from the total RNA isolated from MCF-7/Adr cells by RT-PCR, and subcloned into the pMD19-T vector. The CD44st gene sequence and open reading frame were confirmed by restriction enzyme analysis and nucleotide sequencing, and then inserted into the eukaryotic expression vector pcDNA3.1. The pcDNA3.1-CD44st was transfected into MCF-7 cells using Lipofectamine. After transfection, the positive clones were obtained by G418 screening. The changes of the MMP-2 and MMP-9 genes and protein levels were detected by RT-PCR and gelatin zymography, respectively. The number of the cells penetrating through the artificial matrix membrane in each group (MCF-7, MCF-7+HA, MCF-7/neo, MCF-7/neo+HA, MCF-7/CD44st, MCF-7/CD44st+HA and MCF-7/CD44st+Anti-CD44+HA) was counted to compare the change of the invasion capability regulated by the CD44st. Erk and P-Erk were investigated by Western blotting to approach the molecular mechanisms of MMP-2 and MMP-9 expression regulated by the CD44st. Sensitive MCF-7, Lovo, K562 and HL-60 cells did not contain CD44st mRNA and CD44 protein. In contrast, the multidrug resistance MCF-7/Adr, Lovo/Adr, K562/Adr and HL-60/Adr cells expressed CD44st mRNA and CD44 protein. The CD44st m

Glu20Ter Variant in PLEC 1f Isoform Causes Limb-Girdle Muscle Dystrophy with Lung Injury

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Roman V. Deev

2017-07-01

Full Text Available Plectinopathies are orphan diseases caused by PLEC gene mutations. PLEC is encoding the protein plectin, playing a role in linking cytoskeleton components in various tissues. In this study, we describe the clinical case of a 26-year-old patient with an early onset plectinopathy variant “limb-girdle muscle dystrophy type 2Q,” report histopathological and ultrastructural findings in m. vastus lateralis biopsy and a novel homozygous likely pathogenic variant (NM_201378.3:c.58G>T, NP_958780.1:p.Glu20Ter in isoform 1f of the gene PLEC. The patient had an early childhood onset with retarded physical development, moderate weakness in pelvic girdle muscles, progressive weakening of limb-girdle muscles after the age of 21, pronounced atrophy of axial muscles, and hypertrophy of the gastrocnemius, deltoid, and triceps muscles, intermittent dyspnea, and no skin involvement. Findings included: non-infectious bronchiolitis and atelectasis signs, biopsy revealed myodystrophal pattern without macrophage infiltration, muscle fiber cytoskeleton disorganization resulted from the plectin loss, incomplete reparative rhabdomyogenesis, and moderate endomysial fibrosis. We have determined a novel likely pathogenic variant in PLEC 1f isoform that causes limb-girdle muscle dystrophy type 2Q and described the third case concerning an isolated myodystrophic phenotype of LGMD2Q with the likely pathogenic variant in PLEC 1f isoform. In addition, we have demonstrated the presence of severe lung injury in a patient and his siblings with the same myodystrophic phenotype and discussed the possible role of plectin deficiency in its pathogenesis.

Uncovering the Rare Variants of DLC1 Isoform 1 and Their Functional Effects in a Chinese Sporadic Congenital Heart Disease Cohort

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Wang, Zhen; Tan, Huilian; Kong, Xianghua; Shu, Yang; Zhang, Yuchao; Huang, Yun; Zhu, Yufei; Xu, Heng; Wang, Zhiqiang; Wang, Ping; Ning, Guang; Kong, Xiangyin; Hu, Guohong; Hu, Landian

2014-01-01

Congenital heart disease (CHD) is the most common birth defect affecting the structure and function of fetal hearts. Despite decades of extensive studies, the genetic mechanism of sporadic CHD remains obscure. Deleted in liver cancer 1 (DLC1) gene, encoding a GTPase-activating protein, is highly expressed in heart and essential for heart development according to the knowledge of Dlc1-deficient mice. To determine whether DLC1 is a susceptibility gene for sporadic CHD, we sequenced the coding region of DLC1 isoform 1 in 151 sporadic CHD patients and identified 13 non-synonymous rare variants (including 6 private variants) in the case cohort. Importantly, these rare variants (8/13) were enriched in the N-terminal region of the DLC1 isoform 1 protein. Seven of eight amino acids at the N-terminal variant positions were conserved among the primates. Among the 9 rare variants that were predicted as “damaging”, five were located at the N-terminal region. Ensuing in vitro functional assays showed that three private variants (Met360Lys, Glu418Lys and Asp554Val) impaired the ability of DLC1 to inhibit cell migration or altered the subcellular location of the protein compared to wild-type DLC1 isoform 1. These data suggest that DLC1 might act as a CHD-associated gene in addition to its role as a tumor suppressor in cancer. PMID:24587289

Cooperativity of CD44 and CD49d in leukemia cell homing, migration, and survival offers a means for therapeutic attack.

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Singh, Vibuthi; Erb, Ulrike; Zöller, Margot

2013-11-15

A CD44 blockade drives leukemic cells into differentiation and apoptosis by dislodging from the osteogenic niche. Because anti-CD49d also supports hematopoietic stem cell mobilization, we sought to determine the therapeutic efficacy of a joint CD49d/CD44 blockade. To unravel the underlying mechanism, the CD49d(-) EL4 lymphoma was transfected with CD49d or point-mutated CD49d, prohibiting phosphorylation and FAK binding; additionally, a CD44(-) Jurkat subline was transfected with murine CD44, CD44 with a point mutation in the ezrin binding site, or with cytoplasmic tail-truncated CD44. Parental and transfected EL4 and Jurkat cells were evaluated for adhesion, migration, and apoptosis susceptibility in vitro and in vivo. Ligand-binding and Ab-blocking studies revealed CD44-CD49d cooperation in vitro and in vivo in adhesion, migration, and apoptosis resistance. The cooperation depends on ligand-induced proximity such that both CD44 and CD49d get access to src, FAK, and paxillin and via lck to the MAPK pathway, with the latter also supporting antiapoptotic molecule liberation. Accordingly, synergisms were only seen in leukemia cells expressing wild-type CD44 and CD49d. Anti-CD44 together with anti-CD49d efficiently dislodged EL4-CD49d/Jurkat-CD44 in bone marrow and spleen. Dislodging was accompanied by increased apoptosis susceptibility that strengthened low-dose chemotherapy, the combined treatment most strongly interfering with metastatic settlement and being partly curative. Ab treatment also promoted NK and Ab-dependent cellular cytotoxicity activation, which affected leukemia cells independent of CD44/CD49d tail mutations. Thus, mostly owing to a blockade of joint signaling, anti-CD44 and anti-CD49d hamper leukemic cell settlement and break apoptosis resistance, which strongly supports low-dose chemotherapy.

Mineralization Effect of Hyaluronan on Dental Pulp Cells via CD44.

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Chen, Kuan-Liang; Yeh, Ying-Yi; Lung, Jrhau; Yang, Yu-Chi; Yuan, Kuo

2016-05-01

CD44 is a cell-surface glycoprotein involved in various cellular functions. Recent studies have suggested that CD44 is involved in early mineralization of odontoblasts. Hyaluronic acid (HA) is the principal ligand for receptor CD44. Whether and how HA regulated the mineralization process of dental pulp cells were investigated. The effects of high-molecular-weight HA on differentiation and mineral deposition of dental pulp cells were tested by using alkaline phosphatase (ALP) activity assay and alizarin red S staining. Osteogenesis real-time polymerase chain reaction array, quantitative polymerase chain reaction, and Western blotting were performed to identify downstream molecules involved in the mineralization induction of HA. CD44 was knocked down and examined to confirm whether the mineralization effect of HA was mediated by receptor CD44. Immunohistochemistry was used to understand the localization patterns of CD44 and the identified downstream proteins in vivo. Pulse treatment of HA enhanced ALP activity and mineral deposition in dental pulp cells. Tissue-nonspecific ALP, bone morphogenetic protein 7 (BMP7), and type XV collagen (Col15A1) were upregulated via the HA-CD44 pathway in vitro. Immunohistochemistry of tooth sections showed that the staining pattern of BMP7 was very similar to that of CD44. Results of this study indicated that high-molecular-weight HA enhanced early mineralization of dental pulp cells mediated via CD44. The process involved important mineralization-associated molecules including tissue-nonspecific ALP, BMP7, and Col15A1. The findings may help develop new strategies in regenerative endodontics. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

MicroRNA miR-328 regulates zonation morphogenesis by targeting CD44 expression.

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Wang, Chia-Hui; Lee, Daniel Y; Deng, Zhaoqun; Jeyapalan, Zina; Lee, Shao-Chen; Kahai, Shireen; Lu, Wei-Yang; Zhang, Yaou; Yang, Burton B

2008-06-18

Morphogenesis is crucial to initiate physiological development and tumor invasion. Here we show that a microRNA controls zonation morphogenesis by targeting hyaluronan receptor CD44. We have developed a novel system to study microRNA functions by generating constructs expressing pre-miRNAs and mature miRNAs. Using this system, we have demonstrated that expression of miR-328 reduced cell adhesion, aggregation, and migration, and regulated formation of capillary structure. Protein analysis indicated that miR-328 repressed CD44 expression. Activities of luciferase constructs harboring the target site in CD44, but not the one containing mutation, were repressed by miR-328. Zonation morphogenesis appeared in cells transfected by miR-328: miR-328-transfected cells were present on the surface of zonating structures while the control cells stayed in the middle. MiR-328-mediated CD44 actions was validated by anti-CD44 antibody, hyaluronidase, CD44 siRNA, and CD44 expression constructs. In vivo experiments showed that CD44-silencing cells appeared as layers on the surfaces of nodules or zonating structures. Immuno-histochemistry also exhibited CD44-negative cells on the surface layers of normal rat livers and the internal zones of Portal veins. Our results demonstrate that miR-328 targets CD44, which is essential in regulating zonation morphogenesis: silencing of CD44 expression is essential in sealing the zonation structures to facilitate their extension and to inhibit complex expansion.

MicroRNA miR-328 regulates zonation morphogenesis by targeting CD44 expression.

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Chia-Hui Wang

Full Text Available Morphogenesis is crucial to initiate physiological development and tumor invasion. Here we show that a microRNA controls zonation morphogenesis by targeting hyaluronan receptor CD44. We have developed a novel system to study microRNA functions by generating constructs expressing pre-miRNAs and mature miRNAs. Using this system, we have demonstrated that expression of miR-328 reduced cell adhesion, aggregation, and migration, and regulated formation of capillary structure. Protein analysis indicated that miR-328 repressed CD44 expression. Activities of luciferase constructs harboring the target site in CD44, but not the one containing mutation, were repressed by miR-328. Zonation morphogenesis appeared in cells transfected by miR-328: miR-328-transfected cells were present on the surface of zonating structures while the control cells stayed in the middle. MiR-328-mediated CD44 actions was validated by anti-CD44 antibody, hyaluronidase, CD44 siRNA, and CD44 expression constructs. In vivo experiments showed that CD44-silencing cells appeared as layers on the surfaces of nodules or zonating structures. Immuno-histochemistry also exhibited CD44-negative cells on the surface layers of normal rat livers and the internal zones of Portal veins. Our results demonstrate that miR-328 targets CD44, which is essential in regulating zonation morphogenesis: silencing of CD44 expression is essential in sealing the zonation structures to facilitate their extension and to inhibit complex expansion.

CD44+CD24+ subset of PANC-1 cells exhibits radiation resistance via decreased levels of reactive oxygen species.

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Wang, Lei; Li, Pengping; Hu, Wei; Xia, Youyou; Hu, Chenxi; Liu, Liang; Jiang, Xiaodong

2017-08-01

Emerging evidence has suggested that pancreatic adenocarcinoma is sustained by pancreatic cancer stem cells. The present study aimed to investigate the expression patterns of the pancreatic cancer stem cell surface markers cluster of differentiation CD44 and CD24 in a pancreatic adenocarcinoma cell line, and to investigate the possible mechanisms for their radiation resistance. Flow cytometry was used to analyze the expression patterns of CD44 and CD24 in the pancreatic adenocarcinoma PANC-1 cell line. In addition, a multi-target click model was used to fit cell survival curves and determine the sensitizer enhancement ratio. The apoptosis and cycle distribution of the four cell subsets was determined using flow cytometry, and the level of reactive oxygen species (ROS) was determined using the 2',7'-dichlorofluorescin diacetate probe. The present results identified that the ratios of CD44 + and CD24 + in the sorted PANC-1 cell line were 92.0 and 4.7%, respectively. Prior to radiation, no statistically significant differences were observed among the four groups. Following treatment with 6 MV of X-rays, the rate of apoptosis was decreased in the CD44 + CD24 + group compared with other subsets. The percentage of G0/G1 cells was highest in the CD44 + CD24 + group compared with the three other groups, which exhibited increased radiosensitivity. In addition, the level of ROS in the CD44 + CD24 + group was reduced compared with the other groups. In summary, the results of the present study indicated that CD44 + CD24 + exhibited stem cell properties. The lower level of ROS and apoptosis in CD44 + CD24 + cells may contribute to their resistance to radiation in pancreatic adenocarcinoma.

CD44-engineered mesoporous silica nanoparticles for overcoming multidrug resistance in breast cancer

International Nuclear Information System (INIS)

Wang, Xin; Liu, Ying; Wang, Shouju; Shi, Donghong; Zhou, Xianguang; Wang, Chunyan; Wu, Jiang; Zeng, Zhiyong; Li, Yanjun; Sun, Jing; Wang, Jiandong; Zhang, Longjiang; Teng, Zhaogang; Lu, Guangming

2015-01-01

Graphical abstract: - Highlights: • CD44-engineered mesoporous silica nanoparticles are synthesized. • The mechanism of CD44-engineered mesoporous silica nanoparticles is revealed. • This new delivery system increased the drug accumulation in vitro and in vivo. • This new delivery system offers an effective approach to treat multidrug resistance. - Abstract: Multidrug resistance is a major impediment for the successful chemotherapy in breast cancer. CD44 is over-expressed in multidrug resistant human breast cancer cells. CD44 monoclonal antibody exhibits anticancer potential by inhibiting proliferation and regulating P-glycoprotein-mediated drug efflux activity in multidrug resistant cells. Thereby, CD44 monoclonal antibody in combination with chemotherapeutic drug might be result in enhancing chemosensitivity and overcoming multidrug resistance. The purpose of this study is to investigate the effects of the CD44 monoclonal antibody functionalized mesoporous silica nanoparticles containing doxorubicin on human breast resistant cancer MCF-7 cells. The data showed that CD44-modified mesoporous silica nanoparticles increased cytotoxicity and enhanced the downregulation of P-glycoprotein in comparison to CD44 antibody. Moreover, CD44-engineered mesoporous silica nanoparticles provided active target, which promoted more cellular uptake of DOX in the resistant cells and more retention of DOX in tumor tissues than unengineered counterpart. Animal studies of the resistant breast cancer xenografts demonstrated that CD44-engineered drug delivery system remarkably induced apoptosis and inhibited the tumor growth. Our results indicated that the CD44-engineered mesoporous silica nanoparticle-based drug delivery system offers an effective approach to overcome multidrug resistance in human breast cancer

Low frequency variants in the exons only encoding isoform A of HNF1A do not contribute to susceptibility to type 2 diabetes.

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Bahram Jafar-Mohammadi

2009-08-01

Full Text Available There is considerable interest in the hypothesis that low frequency, intermediate penetrance variants contribute to the proportion of Type 2 Diabetes (T2D susceptibility not attributable to the common variants uncovered through genome-wide association approaches. Genes previously implicated in monogenic and multifactorial forms of diabetes are obvious candidates in this respect. In this study, we focussed on exons 8-10 of the HNF1A gene since rare, penetrant mutations in these exons (which are only transcribed in selected HNF1A isoforms are associated with a later age of diagnosis of Maturity onset diabetes of the young (MODY than mutations in exons 1-7. The age of diagnosis in the subgroup of HNF1A-MODY individuals with exon 8-10 mutations overlaps with that of early multifactorial T2D, and we set out to test the hypothesis that these exons might also harbour low-frequency coding variants of intermediate penetrance that contribute to risk of multifactorial T2D.We performed targeted capillary resequencing of HNF1A exons 8-10 in 591 European T2D subjects enriched for genetic aetiology on the basis of an early age of diagnosis ( or =1 affected sibling. PCR products were sequenced and compared to the published HNF1A sequence. We identified several variants (rs735396 [IVS9-24T>C], rs1169304 [IVS8+29T>C], c.1768+44C>T [IVS9+44C>T] and rs61953349 [c.1545G>A, p.T515T] but no novel non-synonymous coding variants were detected.We conclude that low frequency, nonsynonymous coding variants in the terminal exons of HNF1A are unlikely to contribute to T2D-susceptibility in European samples. Nevertheless, the rationale for seeking low-frequency causal variants in genes known to contain rare, penetrant mutations remains strong and should motivate efforts to screen other genes in a similar fashion.

CD44 antibodies and immune thrombocytopenia in the amelioration of murine inflammatory arthritis.

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Patrick J Mott

Full Text Available Antibodies to CD44 have been used to successfully ameliorate murine models of autoimmune disease. The most often studied disease model has been murine inflammatory arthritis, where a clear mechanism for the efficacy of CD44 antibodies has not been established. We have recently shown in a murine passive-model of the autoimmune disease immune thrombocytopenia (ITP that some CD44 antibodies themselves can induce thrombocytopenia in mice, and the CD44 antibody causing the most severe thrombocytopenia (IM7, also is known to be highly effective in ameliorating murine models of arthritis. Recent work in the K/BxN serum-induced model of arthritis demonstrated that antibody-induced thrombocytopenia reduced arthritis, causing us to question whether CD44 antibodies might primarily ameliorate arthritis through their thrombocytopenic effect. We evaluated IM7, IRAWB14.4, 5035-41.1D, KM201, KM114, and KM81, and found that while all could induce thrombocytopenia, the degree of protection against serum-induced arthritis was not closely related to the length or severity of the thrombocytopenia. CD44 antibody treatment was also able to reverse established inflammation, while thrombocytopenia induced by an anti-platelet antibody targeting the GPIIbIIIa platelet antigen, could not mediate this effect. While CD44 antibody-induced thrombocytopenia may contribute to some of its therapeutic effect against the initiation of arthritis, for established disease there are likely other mechanisms contributing to its efficacy. Humans are not known to express CD44 on platelets, and are therefore unlikely to develop thrombocytopenia after CD44 antibody treatment. An understanding of the relationship between arthritis, thrombocytopenia, and CD44 antibody treatment remains critical for continued development of CD44 antibody therapeutics.

Tumor-Endothelial Interaction Links the CD44+/CD24- Phenotype with Poor Prognosis in Early-Stage Breast Cancer

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Martin Buess

2009-10-01

Conclusions Our results suggest that the interaction of endothelial cells with tumor cells that express the CD44+/CD24- signature, which indicates a low proliferative potential, might explain the unexpected and paradoxical association of the CD44+/CD24- signature with highly proliferative tumors that have an unfavorable prognosis.

Lipid raft association restricts CD44-ezrin interaction and promotion of breast cancer cell migration.

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Donatello, Simona

2012-12-01

Cancer cell migration is an early event in metastasis, the main cause of breast cancer-related deaths. Cholesterol-enriched membrane domains called lipid rafts influence the function of many molecules, including the raft-associated protein CD44. We describe a novel mechanism whereby rafts regulate interactions between CD44 and its binding partner ezrin in migrating breast cancer cells. Specifically, in nonmigrating cells, CD44 and ezrin localized to different membranous compartments: CD44 predominantly in rafts, and ezrin in nonraft compartments. After the induction of migration (either nonspecific or CD44-driven), CD44 affiliation with lipid rafts was decreased. This was accompanied by increased coprecipitation of CD44 and active (threonine-phosphorylated) ezrin-radixin-moesin (ERM) proteins in nonraft compartments and increased colocalization of CD44 with the nonraft protein, transferrin receptor. Pharmacological raft disruption using methyl-β-cyclodextrin also increased CD44-ezrin coprecipitation and colocalization, further suggesting that CD44 interacts with ezrin outside rafts during migration. Conversely, promoting CD44 retention inside lipid rafts by pharmacological inhibition of depalmitoylation virtually abolished CD44-ezrin interactions. However, transient single or double knockdown of flotillin-1 or caveolin-1 was not sufficient to increase cell migration over a short time course, suggesting complex crosstalk mechanisms. We propose a new model for CD44-dependent breast cancer cell migration, where CD44 must relocalize outside lipid rafts to drive cell migration. This could have implications for rafts as pharmacological targets to down-regulate cancer cell migration.

Lipid Raft Association Restricts CD44-Ezrin Interaction and Promotion of Breast Cancer Cell Migration

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Donatello, Simona; Babina, Irina S.; Hazelwood, Lee D.; Hill, Arnold D.K.; Nabi, Ivan R.; Hopkins, Ann M.

2012-01-01

Cancer cell migration is an early event in metastasis, the main cause of breast cancer-related deaths. Cholesterol-enriched membrane domains called lipid rafts influence the function of many molecules, including the raft-associated protein CD44. We describe a novel mechanism whereby rafts regulate interactions between CD44 and its binding partner ezrin in migrating breast cancer cells. Specifically, in nonmigrating cells, CD44 and ezrin localized to different membranous compartments: CD44 predominantly in rafts, and ezrin in nonraft compartments. After the induction of migration (either nonspecific or CD44-driven), CD44 affiliation with lipid rafts was decreased. This was accompanied by increased coprecipitation of CD44 and active (threonine-phosphorylated) ezrin-radixin-moesin (ERM) proteins in nonraft compartments and increased colocalization of CD44 with the nonraft protein, transferrin receptor. Pharmacological raft disruption using methyl-β-cyclodextrin also increased CD44-ezrin coprecipitation and colocalization, further suggesting that CD44 interacts with ezrin outside rafts during migration. Conversely, promoting CD44 retention inside lipid rafts by pharmacological inhibition of depalmitoylation virtually abolished CD44-ezrin interactions. However, transient single or double knockdown of flotillin-1 or caveolin-1 was not sufficient to increase cell migration over a short time course, suggesting complex crosstalk mechanisms. We propose a new model for CD44-dependent breast cancer cell migration, where CD44 must relocalize outside lipid rafts to drive cell migration. This could have implications for rafts as pharmacological targets to down-regulate cancer cell migration. PMID:23031255

A bioengineered murine model using CD24+CD44+ pancreatic cancer stem cells for chemotherapy study

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Qin, Shengqi; Li, Jianshe; Zhang, Zhongtao; Deng, Yiming

2015-01-01

In this work we first developed a murine pancreatic tumor model using CD24 + CD44 + pancreatic cancer stem cells (CSC) supported by an electrospun scaffold. Unlike conventional models, the use of CSC and the scaffold, which were biologically and chemically defined, afforded scientists a reliable platform to evaluate novel chemotherapy regimens. CD24 + CD44 + CSC successfully initiated tumorigenesis in vitro on the scaffold without suffering apoptosis, evidencing the lack of cytotoxicity of scaffolding materials. Also, the scaffold contributed to the acceleration of in vivo tumorigenesis and increased the likelihood of tumor formation. Using this model, we set out to explore the effectiveness of irinotecan/gemcitabine (IRIN-GEM), a chemotherapy regimen, for pancreatic cancer. Our study showed that IRIN-GEM induced a tumor regression whereas gemcitabine alone could only arrest the tumor growth. Further study suggested that the superior performance of IRIN-GEM could be attributed to its capacity to demolish the CD24 + CD44 + CSC sub-population by inducing a large-scale apoptosis. The use of highly proliferative yet homogenous CD24 + CD44 + CSC along with a chemically defined scaffold accelerated the tumor formation and significantly reduced the variability associated with conventional murine models. Armed with this new model, we discovered that IRIN-GEM would be a promising chemotherapy candidate for patients with advanced pancreatic cancer. (paper)

Virtual screening-driven repositioning of etoposide as CD44 antagonist in breast cancer cells

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Aguirre-Alvarado, Charmina; Segura-Cabrera, Aldo; Velázquez-Quesada, Inés; Hernández-Esquivel, Miguel A.; García-Pérez, Carlos A.; Guerrero-Rodríguez, Sandra L.; Ruiz, Angel J.; Rodríguez-Moreno, Andrea; Pérez-Tapia, Sonia M.; Velasco-Velázquez, Marco A.

2016-01-01

CD44 is a receptor for hyaluronan (HA) that promotes epithelial-to-mesenchymal transition (EMT), induces cancer stem cell (CSC) expansion, and favors metastasis. Thus, CD44 is a target for the development of antineoplastic agents. In order to repurpose drugs as CD44 antagonists, we performed consensus-docking studies using the HA-binding domain of CD44 and 11,421 molecules. Drugs that performed best in docking were examined in molecular dynamics simulations, identifying etoposide as a potential CD44 antagonist. Ligand competition and cell adhesion assays in MDA-MB-231 cells demonstrated that etoposide decreased cell binding to HA as effectively as a blocking antibody. Etoposide-treated MDA-MB-231 cells developed an epithelial morphology; increased their expression of E-cadherin; and reduced their levels of EMT-associated genes and cell migration. By gene expression analysis, etoposide reverted an EMT signature similarly to CD44 knockdown, whereas other topoisomerase II (TOP2) inhibitors did not. Moreover, etoposide decreased the proportion of CD44+/CD24− cells, lowered chemoresistance, and blocked mammosphere formation. Our data indicate that etoposide blocks CD44 activation, impairing key cellular functions that drive malignancy, thus rendering it a candidate for further translational studies and a potential lead compound in the development of new CD44 antagonists. PMID:27009862

Increased Toxicity of Chemotherapeutic Drugs by All-Trans Retinoic Acid in Cd44 Cells

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A Abbasi

2016-03-01

Full Text Available BACKGROUND AND OBJECTIVE: In recent studies, undifferentiated CD44 cells have been introduced as the major cause of chemotherapeutic drug resistance in esophageal cancer. In this study, we aimed to evaluate the effects of all-trans retinoic acid on reducing chemotherapeutic drug resistance and improving the associated toxic effects. METHODS: In this clinical study, CD44+ and CD44- cells were separated from KYSE-30 cell line, using magnetic-activated cell sorting (MACS method. The cytotoxic effects of retinoic acid treatment, combined with cisplatin and 5-fluorouracil, were separately evaluated in two cell groups, i.e., CD44+ and CD44-. Cytotoxicity was determined by identifying cellular metabolic activity, acridine orange/ethidium bromide staining, and flow cytometry. FINDINGS: In this study, CD44 marker was expressed in 6.25% of the cell population in KYSE-30 cell line. The results of flow cytometry revealed that treatment with a combination of retinoic acid and chemotherapeutic drugs could improve cell cycle arrest in CD44+ cells (p<0.05, unlike CD44- cells. Determination of cellular metabolic activity, increased cell apoptosis along with decreased half maximal inhibitory concentration (IC50, and acridine orange/ethidium bromide staining were indicative of the increased percentage of primary and secondary apoptotic CD44+ cells. However, in CD44- cells, these effects were only observed by using a combination of retinoic acid and cisplatin (p<0.05. CONCLUSION: The present results showed that all-trans retinoic acid could increase the toxicity of cisplatin and 5-fluorouracil in CD44+ cells.

Overexpression of molecular chaperons GRP78 and GRP94 in CD44(hi)/CD24(lo) breast cancer stem cells.

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Nami, Babak; Ghasemi-Dizgah, Armin; Vaseghi, Akbar

2016-01-01

Breast cancer stem cell with CD44(hi)/CD24(lo) phonotype is described having stem cell properties and represented as the main driving factor in breast cancer initiation, growth, metastasis and low response to anti-cancer agents. Glucoseregulated proteins (GRPs) are heat shock protein family chaperons that are charged with regulation of protein machinery and modulation of endoplasmic reticulum homeostasis whose important roles in stem cell development and invasion of various cancers have been demonstrated. Here, we investigated the expression levels of GRP78 and GRP94 in CD44(hi)/CD24(lo) phenotype breast cancer stem cells (BCSCs). MCF7, T-47D and MDA-MB-231 breast cancer cell lines were used. CD44(hi)/CD24(lo) phenotype cell population were analyzed and sorted by fluorescence-activated cell sorting (FACS). Transcriptional and translational expression of GRP78 and GRP94 were investigated by western blotting and quantitative real time PCR. RESULTS showed different proportion of CD44(hi)/CD24(lo) phenotype cell population in their original bulk cells. The ranking of the cell lines in terms of CD44(hi)/CD24(lo) phenotype cell population was as MCF7hi)/CD24(lo) phenotype cells exhibited higher mRNA and protein expression level of GRP78 and GRP94 compared to their original bulk cells. Our results show a relationship between overexpression of GRP78 and GRP94 and exhibiting CD44hi/CD24lo phenotype in breast cancer cells. We conclude that upregulation of GRPs may be an important factor in the emergence of CD44hi/CD24lo phenotype BCSCs features.

Intracellular targeting of CD44+ cells with self-assembling, protein only nanoparticles.

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Pesarrodona, Mireia; Ferrer-Miralles, Neus; Unzueta, Ugutz; Gener, Petra; Tatkiewicz, Witold; Abasolo, Ibane; Ratera, Imma; Veciana, Jaume; Schwartz, Simó; Villaverde, Antonio; Vazquez, Esther

2014-10-01

CD44 is a multifunctional cell surface protein involved in proliferation and differentiation, angiogenesis and signaling. The expression of CD44 is up-regulated in several types of human tumors and particularly in cancer stem cells, representing an appealing target for drug delivery in the treatment of cancer. We have explored here several protein ligands of CD44 for the construction of self-assembling modular proteins designed to bind and internalize target cells. Among five tested ligands, two of them (A5G27 and FNI/II/V) drive the formation of protein-only, ring-shaped nanoparticles of about 14 nm that efficiently bind and penetrate CD44(+) cells by an endosomal route. The potential of these newly designed nanoparticles is evaluated regarding the need of biocompatible nanostructured materials for drug delivery in CD44-linked conditions. Copyright © 2014 Elsevier B.V. All rights reserved.

Expression of CD44v6 and Its Association with Prognosis in Epithelial Ovarian Carcinomas

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Dang-xia Zhou

2012-01-01

Full Text Available The aim of this study was to evaluate CD44v6 protein expression and its prognostic value of CD44v6 in ovarian carcinoma. The expression of CD44v6 was analyzed in 62 patients with ovarian carcinoma by immunohistochemical method. The data obtained were analyzed by univariate and multivariate analyses. The present study clearly demonstrates that tumor tissues from 41 (66.1% patients showed positive expression with CD44v6. The expression of CD44v6 was significantly correlated with histological type, FIGO stage and histological grade of ovarian carcinomas. Concerning the prognosis, the survival period of patients with CD44v6 positive was shorter than that of patients with CD44v6 negative (36.6% versus 66.7%, 5-year survival, P<0.05. Univariate analysis showed that CD44v6 expression, histological type, FIGO stage and histological grade were associated with 5-year survival, and CD44v6 expression was associated with histological type, FIGO stage and histological grade and 5-year survival. In multivariate analysis, using the COX-regression model, CD44v6 expression was important prognostic factor. In conclusion, these results suggest that CD44v6 may be related to histological type, FIGO stage and histological grade of ovarian carcinomas, and CD44v6 may be an important molecular marker for poor prognosis in ovarian carcinomas.

CD44 regulates cell migration in human colon cancer cells via Lyn kinase and AKT phosphorylation.

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Subramaniam, Venkateswaran; Vincent, Isabella R; Gardner, Helena; Chan, Emily; Dhamko, Helena; Jothy, Serge

2007-10-01

Colon cancer is among the leading causes of cancer death in North America. CD44, an adhesion and antiapoptotic molecule is overexpressed in colon cancer. Cofilin is involved in the directional motility of cells. In the present study, we looked at how CD44 might modulate cell migration in human colon cancer via cofilin. We used a human colon cancer cell line, HT29, which expresses CD44, HT29 where CD44 expression was knocked down by siRNA, SW620, a human colon cancer cell line which does not express CD44, stably transfected exons of CD44 in SW620 cells and the colon from CD44 knockout and wild-type mouse. Western blot analysis of siRNA CD44 lysates showed increased level of AKT phosphorylation and decreased level of cofilin expression. Similar results were also observed with SW620 cells and CD44 knockout mouse colon lysates. Experiments using the AKT phosphorylation inhibitor LY294002 indicate that AKT phosphorylation downregulates cofilin. Immunoprecipitation studies showed CD44 complex formation with Lyn, providing an essential link between CD44 and AKT phosphorylation. LY294002 also stabilized Lyn from phosphorylated AKT, suggesting an interaction between Lyn and AKT phosphorylation. Immunocytochemistry showed that cofilin and Lyn expression were downregulated in siRNA CD44 cells and CD44 knockout mouse colon. siRNA CD44 cells had significantly less migration compared to HT29 vector. Given the well-defined roles of CD44, phosphorylated AKT in apoptosis and cancer, these results indicate that CD44-induced cell migration is dependent on its complex formation with Lyn and its consequent regulation of AKT phosphorylation and cofilin expression.

In Vitro and In Vivo Prostate Cancer Metastasis and Chemoresistance Can Be Modulated by Expression of either CD44 or CD147

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Hao, Jingli; Madigan, Michele C.; Khatri, Aparajita; Power, Carl A.; Hung, Tzong-Tyng; Beretov, Julia; Chang, Lei; Xiao, Weiwei; Cozzi, Paul J.; Graham, Peter H.; Kearsley, John H.; Li, Yong

2012-01-01

CD44 and CD147 are associated with cancer metastasis and progression. Our purpose in the study was to investigate the effects of down-regulation of CD44 or CD147 on the metastatic ability of prostate cancer (CaP) cells, their docetaxel (DTX) responsiveness and potential mechanisms involved in vitro and in vivo. CD44 and CD147 were knocked down (KD) in PC-3M-luc CaP cells using short hairpin RNA (shRNA). Expression of CD44, CD147, MRP2 (multi-drug resistance protein-2) and MCT4 (monocarboxylate tranporter-4) was evaluated using immunofluorescence and Western blotting. The DTX dose-response and proliferation was measured by MTT and colony assays, respectively. The invasive potential was assessed using a matrigel chamber assay. Signal transduction proteins in PI3K/Akt and MAPK/Erk pathways were assessed by Western blotting. An in vivo subcutaneous (s.c.) xenograft model was established to assess CaP tumorigenecity, lymph node metastases and DTX response. Our results indicated that KD of CD44 or CD147 decreased MCT4 and MRP2 expression, reduced CaP proliferation and invasive potential and enhanced DTX sensitivity; and KD of CD44 or CD147 down-regulated p-Akt and p-Erk, the main signal modulators associated with cell growth and survival. In vivo, CD44 or CD147-KD PC-3M-luc xenografts displayed suppressed tumor growth with increased DTX responsiveness compared to control xenografts. Both CD44 and CD147 enhance metastatic capacity and chemoresistance of CaP cells, potentially mediated by activation of the PI3K and MAPK pathways. Selective targeting of CD44/CD147 alone or combined with DTX may limit CaP metastasis and increase chemosensitivity, with promise for future CaP treatment. PMID:22870202

In vitro and in vivo prostate cancer metastasis and chemoresistance can be modulated by expression of either CD44 or CD147.

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Jingli Hao

Full Text Available CD44 and CD147 are associated with cancer metastasis and progression. Our purpose in the study was to investigate the effects of down-regulation of CD44 or CD147 on the metastatic ability of prostate cancer (CaP cells, their docetaxel (DTX responsiveness and potential mechanisms involved in vitro and in vivo. CD44 and CD147 were knocked down (KD in PC-3M-luc CaP cells using short hairpin RNA (shRNA. Expression of CD44, CD147, MRP2 (multi-drug resistance protein-2 and MCT4 (monocarboxylate tranporter-4 was evaluated using immunofluorescence and Western blotting. The DTX dose-response and proliferation was measured by MTT and colony assays, respectively. The invasive potential was assessed using a matrigel chamber assay. Signal transduction proteins in PI3K/Akt and MAPK/Erk pathways were assessed by Western blotting. An in vivo subcutaneous (s.c. xenograft model was established to assess CaP tumorigenecity, lymph node metastases and DTX response. Our results indicated that KD of CD44 or CD147 decreased MCT4 and MRP2 expression, reduced CaP proliferation and invasive potential and enhanced DTX sensitivity; and KD of CD44 or CD147 down-regulated p-Akt and p-Erk, the main signal modulators associated with cell growth and survival. In vivo, CD44 or CD147-KD PC-3M-luc xenografts displayed suppressed tumor growth with increased DTX responsiveness compared to control xenografts. Both CD44 and CD147 enhance metastatic capacity and chemoresistance of CaP cells, potentially mediated by activation of the PI3K and MAPK pathways. Selective targeting of CD44/CD147 alone or combined with DTX may limit CaP metastasis and increase chemosensitivity, with promise for future CaP treatment.

Non-Small Cell Lung Cancer Cells Expressing CD44 Are Enriched for Stem Cell-Like Properties

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Leung, Elaine Lai-Han; Fiscus, Ronald R.; Tung, James W.; Tin, Vicky Pui-Chi; Cheng, Lik Cheung; Sihoe, Alan Dart-Loon; Fink, Louis M.; Ma, Yupo; Wong, Maria Pik

2010-01-01

Background The cancer stem cell theory hypothesizes that cancers are perpetuated by cancer stem cells (CSC) or tumor initiating cells (TIC) possessing self-renewal and other stem cell-like properties while differentiated non-stem/initiating cells have a finite life span. To investigate whether the hypothesis is applicable to lung cancer, identification of lung CSC and demonstration of these capacities is essential. Methodology/Principal Finding The expression profiles of five stem cell markers (CD34, CD44, CD133, BMI1 and OCT4) were screened by flow cytometry in 10 lung cancer cell lines. CD44 was further investigated by testing for in vitro and in vivo tumorigenecity. Formation of spheroid bodies and in vivo tumor initiation ability were demonstrated in CD44+ cells of 4 cell lines. Serial in vivo tumor transplantability in nude mice was demonstrated using H1299 cell line. The primary xenografts initiated from CD44+ cells consisted of mixed CD44+ and CD44− cells in similar ratio as the parental H1299 cell line, supporting in vivo differentiation. Semi-quantitative Real-Time PCR (RT-PCR) showed that both freshly sorted CD44+ and CD44+ cells derived from CD44+-initiated tumors expressed the pluripotency genes OCT4/POU5F1, NANOG, SOX2. These stemness markers were not expressed by CD44− cells. Furthermore, freshly sorted CD44+ cells were more resistant to cisplatin treatment with lower apoptosis levels than CD44− cells. Immunohistochemical analysis of 141 resected non-small cell lung cancers showed tumor cell expression of CD44 in 50.4% of tumors while no CD34, and CD133 expression was observed in tumor cells. CD44 expression was associated with squamous cell carcinoma but unexpectedly, a longer survival was observed in CD44-expressing adenocarcinomas. Conclusion/Significance Overall, our results demonstrated that stem cell-like properties are enriched in CD44-expressing subpopulations of some lung cancer cell lines. Further investigation is required to clarify

Myosin 1g Contributes to CD44 Adhesion Protein and Lipid Rafts Recycling and Controls CD44 Capping and Cell Migration in B Lymphocytes

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Orestes López-Ortega

2017-12-01

Full Text Available Cell migration and adhesion are critical for immune system function and involve many proteins, which must be continuously transported and recycled in the cell. Recycling of adhesion molecules requires the participation of several proteins, including actin, tubulin, and GTPases, and of membrane components such as sphingolipids and cholesterol. However, roles of actin motor proteins in adhesion molecule recycling are poorly understood. In this study, we identified myosin 1g as one of the important motor proteins that drives recycling of the adhesion protein CD44 in B lymphocytes. We demonstrate that the lack of Myo1g decreases the cell-surface levels of CD44 and of the lipid raft surrogate GM1. In cells depleted of Myo1g, the recycling of CD44 was delayed, the delay seems to be caused at the level of formation of recycling complex and entry into recycling endosomes. Moreover, a defective lipid raft recycling in Myo1g-deficient cells had an impact both on the capping of CD44 and on cell migration. Both processes required the transportation of lipid rafts to the cell surface to deliver signaling components. Furthermore, the extramembrane was essential for cell expansion and remodeling of the plasma membrane topology. Therefore, Myo1g is important during the recycling of lipid rafts to the membrane and to the accompanied proteins that regulate plasma membrane plasticity. Thus, Myosin 1g contributes to cell adhesion and cell migration through CD44 recycling in B lymphocytes.

Neutrophil transmigration mediated by the neutrophil-specific antigen CD177 is influenced by the endothelial S536N dimorphism of platelet endothelial cell adhesion molecule-1.

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Bayat, Behnaz; Werth, Silke; Sachs, Ulrich J H; Newman, Debra K; Newman, Peter J; Santoso, Sentot

2010-04-01

The human neutrophil-specific adhesion molecule CD177 (also known as the NB1 alloantigen) becomes upregulated on the cell surface in a number of inflammatory settings. We recently showed that CD177 functions as a novel heterophilic counterreceptor for the endothelial junctional protein PECAM-1 (CD31), an interaction that is mediated by membrane-proximal PECAM-1 IgD 6, which is known to harbor an S(536)N single nucleotide polymorphism of two major isoforms V(98)N(536)G(643) and L(98)S(536)R(643) and a yet-to-be-determined region on CD177. In vitro transendothelial migration experiments revealed that CD177(+) neutrophils migrated significantly faster through HUVECs expressing the LSR, compared with the VNG, allelic variant of PECAM-1 and that this correlated with the decreased ability of anti-PECAM-1 Ab of ITIM tyrosine phosphorylation in HUVECs expressing the LSR allelic variant relative to the VNG allelic variant. Moreover, engagement of PECAM-1 with rCD177-Fc (to mimic heterophilic CD177 binding) suppressed Ab-induced tyrosine phosphorylation to a greater extent in cells expressing the LSR isoform compared with the VNG isoform, with a corresponding increased higher level of beta-catenin phosphorylation. These data suggest that heterophilic PECAM-1/CD177 interactions affect the phosphorylation state of PECAM-1 and endothelial cell junctional integrity in such a way as to facilitate neutrophil transmigration in a previously unrecognized allele-specific manner.

Significance of CD44 expression in head and neck cancer: a systemic review and meta-analysis

International Nuclear Information System (INIS)

Chen, Jianqiang; Zhou, Jianding; Lu, Jie; Xiong, Hua; Shi, Xueli; Gong, Liang

2014-01-01

CD44 has been reported to be involved with tumor growth and metastasis and has also been implicated as a CSC marker in head and neck squamous cell cancer (HNSCC). However, the prognostic value of CD44 still remains controversial; hence, we investigated the correlation between CD44 and the clinicopathological features of HNSCC by meta-analysis. A comprehensive search was performed using PubMed, ISI web of Science and China National Knowledge Infrastructure (CNKI) up to April 2013. Only studies with immunohistochemical staining of HNSCC were considered. Data on TNM classification, tumor grade, disease free survival and 3- or 5-year overall survival rate were extracted. Thirty studies with 2102 patients met the inclusion criteria for the meta-analysis. Fifteen studies used anti-pan-CD44 antibody, 9 used anti-CD44-v6 antibody, 2 used anti-CD44-v3 and 2 used anti-CD44s antibody, 1 used anti-CD44-v9, and 1 used anti-CD44-v6,-v3 and -v4-5 simultaneously. The total percentage of CD44 expression was 57.8%, with 49.3% in oral cancer patients, 66.4% in pharynx and 54.7% in larynx cancer patients expressing CD44. No significant correlation between clinical features and CD44 expression was revealed for oral cancer patients, but CD44 was shown to be associated with advanced T categories (larynx: RR = 1.33, 95% CI 1.01-1.76; larynx & pharynx RR = 1.21, 95% CI 1.08-1.35), worse N categories (larynx: RR = 2.53, 95% CI 1.99-3.21; larynx & pharynx RR = 1.95, 95% CI 1.35-2.82), higher tumor grades (larynx & pharynx RR = 1.71, 95% CI 1.04-2.79) and 5-year OS rates (larynx: RR = 0.62, 95% CI 0.47-0.83; larynx & pharynx RR = 0.66, 95% CI 0.47-0.94) in patients with laryngeal and pharyngolaryngeal cancer. In stratified analysis, pan-CD44 and CD44-v6 expression were both correlated with 5-year OS rate of patients with laryngeal (CD44: RR = 0.66, 95% CI 0.46-0.95; CD44-v6 RR = 0.53, 95% CI 0.37-0.77) and pharyngolaryngeal cancer (CD44: RR = 0.56, 95% CI 0.34-0.93; CD44-v6 RR = 0.53, 95% CI

Differentiation of breast cancer stem cells by knockdown of CD44: promising differentiation therapy

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Pham Phuc V

2011-12-01

Full Text Available Abstract Background Breast cancer stem cells (BCSCs are the source of breast tumors. Compared with other cancer cells, cancer stem cells show high resistance to both chemotherapy and radiotherapy. Targeting of BCSCs is thus a potentially promising and effective strategy for breast cancer treatment. Differentiation therapy represents one type of cancer stem-cell-targeting therapy, aimed at attacking the stemness of cancer stem cells, thus reducing their chemo- and radioresistance. In a previous study, we showed that down-regulation of CD44 sensitized BCSCs to the anti-tumor agent doxorubicin. This study aimed to determine if CD44 knockdown caused BCSCs to differentiate into breast cancer non-stem cells (non-BCSCs. Methods We isolated a breast cancer cell population (CD44+CD24- cells from primary cultures of malignant breast tumors. These cells were sorted into four sub-populations based on their expression of CD44 and CD24 surface markers. CD44 knockdown in the BCSC population was achieved using small hairpin RNA lentivirus particles. The differentiated status of CD44 knock-down BCSCs was evaluated on the basis of changes in CD44+CD24- phenotype, tumorigenesis in NOD/SCID mice, and gene expression in relation to renewal status, metastasis, and cell cycle in comparison with BCSCs and non-BCSCs. Results Knockdown of CD44 caused BCSCs to differentiate into non-BCSCs with lower tumorigenic potential, and altered the cell cycle and expression profiles of some stem cell-related genes, making them more similar to those seen in non-BCSCs. Conclusions Knockdown of CD44 is an effective strategy for attacking the stemness of BCSCs, resulting in a loss of stemness and an increase in susceptibility to chemotherapy or radiation. The results of this study highlight a potential new strategy for breast cancer treatment through the targeting of BCSCs.

Lack of Association of CD55 Receptor Genetic Variants and Severe Malaria in Ghanaian Children

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Kathrin Schuldt

2017-03-01

Full Text Available In a recent report, the cellular receptor CD55 was identified as a molecule essential for the invasion of human erythrocytes by Plasmodium falciparum, the causal agent of the most severe form of malaria. As this invasion process represents a critical step during infection with the parasite, it was hypothesized that genetic variants in the gene could affect severe malaria (SM susceptibility. We performed high-resolution variant discovery of rare and common genetic variants in the human CD55 gene. Association testing of these variants in over 1700 SM cases and unaffected control individuals from the malaria-endemic Ashanti Region in Ghana, West Africa, were performed on the basis of single variants, combined rare variant analyses, and reconstructed haplotypes. A total of 26 genetic variants were detected in coding and regulatory regions of CD55. Five variants were previously unknown. None of the single variants, rare variants, or haplotypes showed evidence for association with SM or P. falciparum density. Here, we present the first comprehensive analysis of variation in the CD55 gene in the context of SM and show that genetic variants present in a Ghanaian study group appear not to influence susceptibility to the disease.

Prognostic significance of CD44s expression in resected non-small cell lung cancer

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Ko Yoon

2011-08-01

Full Text Available Abstract Background CD44s is a cell adhesion molecule known to mediate cellular adhesion to the extracellular matrix, a prerequisite for tumor cell migration. CD44s plays an important role in invasion and metastasis of various cancers. In the present study, we sought to determine whether CD44s is involved in clinical outcomes of patients with resected non-small cell lung cancer (NSCLC. Methods Using immunohistochemical staining, we investigated CD44s protein expression using tissue array specimens from 159 patients with resected NSCLC (adenocarcinoma (AC; n = 82 and squamous cell carcinoma (SCC; n = 77. Additionally, the immunoreactivity of cyclooxygenase (COX-2 was also studied. The clinicopathological implications of these molecules were analyzed statistically. Results High CD44s expression was detected more frequently in NSCLC patients with SCC (66/72; 91.7% than in those with AC histology (P 0.001. Additionally, high CD44s expression was significant correlated with more advanced regional lymph node metastasis (P = 0.021. In multivariate analysis of survival in NSCLC patients with AC histology, significant predictors were lymph node metastasis status (P P = 0.046, and high CD44s expression (P = 0.014. For NSCLC patients with SCC histology, the significant predictor was a more advanced tumor stage (P = 0.015. No significant association was found between CD44s and clinical outcome (P = 0.311. Conclusions High CD44s expression was a negative prognostic marker with significance in patients with resected NSCLC, particularly those with AC histology, and was independent of tumor stage.

Prognostic significance of CD44s expression in resected non-small cell lung cancer

International Nuclear Information System (INIS)

Ko, Yoon Ho; Won, Hye Sung; Jeon, Eun Kyoung; Hong, Sook Hee; Roh, Sang Young; Hong, Young Seon; Byun, Jae Ho; Jung, Chan-Kwon; Kang, Jin Hyoung

2011-01-01

CD44s is a cell adhesion molecule known to mediate cellular adhesion to the extracellular matrix, a prerequisite for tumor cell migration. CD44s plays an important role in invasion and metastasis of various cancers. In the present study, we sought to determine whether CD44s is involved in clinical outcomes of patients with resected non-small cell lung cancer (NSCLC). Using immunohistochemical staining, we investigated CD44s protein expression using tissue array specimens from 159 patients with resected NSCLC (adenocarcinoma (AC; n = 82) and squamous cell carcinoma (SCC; n = 77). Additionally, the immunoreactivity of cyclooxygenase (COX)-2 was also studied. The clinicopathological implications of these molecules were analyzed statistically. High CD44s expression was detected more frequently in NSCLC patients with SCC (66/72; 91.7%) than in those with AC histology (P <0.001). Additionally, high CD44s expression was significant correlated with more advanced regional lymph node metastasis (P = 0.021). In multivariate analysis of survival in NSCLC patients with AC histology, significant predictors were lymph node metastasis status (P < 0.001), high-grade tumor differentiation (P = 0.046), and high CD44s expression (P = 0.014). For NSCLC patients with SCC histology, the significant predictor was a more advanced tumor stage (P = 0.015). No significant association was found between CD44s and clinical outcome (P = 0.311). High CD44s expression was a negative prognostic marker with significance in patients with resected NSCLC, particularly those with AC histology, and was independent of tumor stage

HAb18G/CD147 Promotes pSTAT3-Mediated Pancreatic Cancer Development via CD44s †, ‡

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Li, Ling; Tang, Wenhua; Wu, Xiaoqing; Karnak, David; Meng, Xiaojie; Thompson, Rachel; Hao, Xinbao; Li, Yongmin; Qiao, Xiaotan T.; Lin, Jiayuh; Fuchs, James; Simeone, Diane M.; Chen, Zhi-Nan; Lawrence, Theodore S.; Xu, Liang

2013-01-01

Purpose STAT3 plays a critical role in initiation and progression of pancreatic cancer. However, therapeutically targeting STAT3 is failure in clinic. We previously identified HAb18G/CD147 as an effective target for cancer treatment. In this study, we aimed to investigate potential role of HAb18G/CD147 in STAT3-involved pancreatic tumorigenesis in vitro and in vivo. Experimental Design The expression of HAb18G/CD147, pSTAT3 and CD44s were determined in tissue microarrays. The tumorigenic function and molecular signaling mechanism of HAb18G/CD147 was assessed by in vitro cellular and clonogenic growth, reporter assay, immunoblot, immunofluorescence staining, immunoprecipitation, and in vivo tumor formationusing loss or gain-of-function strategies. Results Highly expressed HAb18G/CD147 promoted cellular and clonogenic growth in vitro and tumorigenicity in vivo. CyPA, a ligand of CD147, stimulated STAT3 phosphorylation and its downstream genes cyclin D1/survivin through HAb18G/CD147 dependent mechanisms. HAb18G/CD147 was associated and co-localized with cancer stem cell marker CD44s in lipid rafts. The inhibitors of STAT3 and survivin, as well as CD44s neutralizing antibodies suppressed the HAb18G/CD147-induced cell growth. High HAb18G/CD147 expression in pancreatic cancer was significantly correlated with the poor tumor differentiation, and the high co-expression of HAb18G/CD147-CD44s-STAT3 associated with poor survival of patients with pancreatic cancer. Conclusions We identified HAb18G/CD147 as a novel upstream activator of STAT3 via interacts with CD44s and plays a critical role in the development of pancreatic cancer. The data suggest HAb18G/CD147 could be a promising therapeutic target for highly aggressive pancreatic cancer and a surrogate marker in the STAT3-targeted molecular therapies. PMID:24132924

ALDH/CD44 identifies uniquely tumorigenic cancer stem cells in salivary gland mucoepidermoid carcinomas.

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Adams, April; Warner, Kristy; Pearson, Alexander T; Zhang, Zhaocheng; Kim, Hong Sun; Mochizuki, Daiki; Basura, Gregory; Helman, Joseph; Mantesso, Andrea; Castilho, Rogério M; Wicha, Max S; Nör, Jacques E

2015-09-29

A small sub-population of cells characterized by increased tumorigenic potential, ability to self-renew and to differentiate into cells that make up the tumor bulk, has been characterized in some (but not all) tumor types. These unique cells, namedcancer stem cells, are considered drivers of tumor progression in these tumors. The purpose of this work is to understand if cancer stem cells play a functional role in the tumorigenesis of salivary gland mucoepidermoid carcinomas. Here, we investigated the expression of putative cancer stem cell markers (ALDH, CD10, CD24, CD44) in primary human mucoepidermoid carcinomas by immunofluorescence, in vitro salisphere assays, and in vivo tumorigenicity assays in immunodeficient mice. Human mucoepidermoid carcinoma cells (UM-HMC-1, UM-HMC-3A, UM-HMC-3B) sorted for high levels of ALDH activity and CD44 expression (ALDHhighCD44high) consistently formed primary and secondary salispheres in vitro, and showed enhanced tumorigenic potential in vivo (defined as time to tumor palpability, tumor growth after palpability), when compared to ALDHlowCD44low cells. Cells sorted for CD10/CD24, and CD10/CD44 showed varying trends of salisphere formation, but consistently low in vivo tumorigenic potential. And finally, cells sorted for CD44/CD24 showed inconsistent results in salisphere formation and tumorigenic potential assays when different cell lines were evaluated. Collectively, these data demonstrate that salivary gland mucoepidermoid carcinomas contain a small population of cancer stem cells with enhanced tumorigenic potential and that are characterized by high ALDH activity and CD44 expression. These results suggest that patients with mucoepidermoid carcinoma might benefit from therapies that ablate these highly tumorigenic cells.

CD147, CD44, and the epidermal growth factor receptor (EGFR) signaling pathway cooperate to regulate breast epithelial cell invasiveness.

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Grass, G Daniel; Tolliver, Lauren B; Bratoeva, Momka; Toole, Bryan P

2013-09-06

The immunoglobulin superfamily glycoprotein CD147 (emmprin; basigin) is associated with an invasive phenotype in various types of cancers, including malignant breast cancer. We showed recently that up-regulation of CD147 in non-transformed, non-invasive breast epithelial cells is sufficient to induce an invasive phenotype characterized by membrane type-1 matrix metalloproteinase (MT1-MMP)-dependent invadopodia activity (Grass, G. D., Bratoeva, M., and Toole, B. P. (2012) Regulation of invadopodia formation and activity by CD147. J. Cell Sci. 125, 777-788). Here we found that CD147 induces breast epithelial cell invasiveness by promoting epidermal growth factor receptor (EGFR)-Ras-ERK signaling in a manner dependent on hyaluronan-CD44 interaction. Furthermore, CD147 promotes assembly of signaling complexes containing CD147, CD44, and EGFR in lipid raftlike domains. We also found that oncogenic Ras regulates CD147 expression, hyaluronan synthesis, and formation of CD147-CD44-EGFR complexes, thus forming a positive feedback loop that may amplify invasiveness. Last, we showed that malignant breast cancer cells are heterogeneous in their expression of surface-associated CD147 and that high levels of membrane CD147 correlate with cell surface EGFR and CD44 levels, activated EGFR and ERK1, and activated invadopodia. Future studies should evaluate CD147 as a potential therapeutic target and disease stratification marker in breast cancer.

CD147, CD44, and the Epidermal Growth Factor Receptor (EGFR) Signaling Pathway Cooperate to Regulate Breast Epithelial Cell Invasiveness*

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Grass, G. Daniel; Tolliver, Lauren B.; Bratoeva, Momka; Toole, Bryan P.

2013-01-01

The immunoglobulin superfamily glycoprotein CD147 (emmprin; basigin) is associated with an invasive phenotype in various types of cancers, including malignant breast cancer. We showed recently that up-regulation of CD147 in non-transformed, non-invasive breast epithelial cells is sufficient to induce an invasive phenotype characterized by membrane type-1 matrix metalloproteinase (MT1-MMP)-dependent invadopodia activity (Grass, G. D., Bratoeva, M., and Toole, B. P. (2012) Regulation of invadopodia formation and activity by CD147. J. Cell Sci. 125, 777–788). Here we found that CD147 induces breast epithelial cell invasiveness by promoting epidermal growth factor receptor (EGFR)-Ras-ERK signaling in a manner dependent on hyaluronan-CD44 interaction. Furthermore, CD147 promotes assembly of signaling complexes containing CD147, CD44, and EGFR in lipid raftlike domains. We also found that oncogenic Ras regulates CD147 expression, hyaluronan synthesis, and formation of CD147-CD44-EGFR complexes, thus forming a positive feedback loop that may amplify invasiveness. Last, we showed that malignant breast cancer cells are heterogeneous in their expression of surface-associated CD147 and that high levels of membrane CD147 correlate with cell surface EGFR and CD44 levels, activated EGFR and ERK1, and activated invadopodia. Future studies should evaluate CD147 as a potential therapeutic target and disease stratification marker in breast cancer. PMID:23888049

Experimental study on the expression of CD44 and CD54 in liver metastasis of colorectal carcinoma

International Nuclear Information System (INIS)

Ma Chen; Mao Dabeng; Wang Chengzhong; Guo Yu

2004-01-01

Objective: To study the significance of CD44 and CD54 expression in animal models with liver metastasis of colorectal cancer and try to find a stable biological marker for the early diagnosis of liver metastasis of colorectal cancer. Methods: Fourth two nude mice of 4-6 wks were adopted in the study. Thirty-six were used to establish animal models with liver metastasis of colorectal cancer, the rest 6 mice were used as the controls. 36 mice of the experimental group were divided into 6 subgroups, each containing 6 mice, in which low grade colorectal adenocarcinoma cells were injected in the subcapsule of the spleen. On the day 10th, 15th, 20th, 25th, 30th day and at the time of the brink of death, animas in each subgroup were sacrificed by eyeball removal and blood letting. Serum CD44, CD54 and CEA levels of the nude mice were measured by ELISA and the sizes and number of liver metastatic loci were observed and noted. the 6 mice for control were raised in the same cages and were killed on the 30th day, and were compared with that in the experimental group. Results: Through the measurement at different phrases, authors found with the development progression and metastasis of cancer, CD44 and CD54 levels in the animal serum tend to increase gradually and were correlated positively with the growth time, size, and extent metastasis of the cancer. Conclusion: CD44 and CD54 may be early tumor markers for liver metastasis of colorectal cancer

Effects of CD44 Ligation on Signaling and Metabolic Pathways in Acute Myeloid Leukemia

KAUST Repository

Madhoun, Nour Y.

2017-04-01

Acute myeloid leukemia (AML) is characterized by a blockage in the differentiation of myeloid cells at different stages. CD44-ligation using anti-CD44 monoclonal antibodies (mAbs) has been shown to reverse the blockage of differentiation and to inhibit the proliferation of blasts in most AML-subtypes. However, the molecular mechanisms underlying this property have not been fully elucidated. Here, we sought to I) analyze the effects of anti-CD44 mAbs on downstream signaling pathways, including the ERK1/2 (extracellular signal-regulated kinase 1 and 2) and mTOR (mammalian target of rapamycin) pathways and II) use state-of-the-art Nuclear Magnetic Resonance (NMR) technology to determine the global metabolic changes during differentiation induction of AML cells using anti-CD44 mAbs and other two previously reported differentiation agents. In the first objective (Chapter 4), our studies provide evidence that CD44-ligation with specific mAbs in AML cells induced an increase in ERK1/2 phosphorylation. The use of the MEK inhibitor (U0126) significantly inhibited the CD44-induced differentiation of HL60 cells, suggesting that ERK1/2 is critical for the CD44-triggered differentiation in AML. In addition, this was accompanied by a marked decrease in the phosphorylation of the mTORC1 and mTORC2 complexes, which are strongly correlated with the inhibition of the PI3K/Akt pathway. In the second objective (Chapter 5), 1H NMR experiments demonstrated that considerable changes in the metabolic profiles of HL60 cells were induced in response to each differentiation agent. These most notable metabolites that significantly changed upon CD44 ligation were involved in the tricarboxylic acid (TCA) cycle and glycolysis such as, succinate, fumarate and lactate. Therefore, we sought to analyze the mechanisms underlying their alterations. Our results revealed that anti-CD44 mAbs treatment induced upregulation in fumarate hydratase (FH) expression and its activity which was accompanied by a

CRISPR-Cas9-Mediated Silencing of CD44 in Human Highly Metastatic Osteosarcoma Cells

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Tang Liu

2018-04-01

Full Text Available Background/Aims: Metastasis is the major cause of death in patients with osteosarcoma. There is an urgent need to identify molecular markers that promote metastasis. Cluster of differentiation 44 is a receptor for hyaluronic acid (HA and HA-binding has been proven to participate in various biological tumor activities, including tumor progression and metastasis. Methods: We performed a meta-analysis to investigate the relationship between CD44 expression, survival, and metastasis in patients with osteosarcoma. We then utilized the CRISPR-Cas9 system to specifically silence CD44 in highly metastatic human osteosarcoma cells (MNNG/HOS and 143B and further determined the functional effects of CD44 knockout in these cells. Results: The meta-analysis demonstrated that a high level of CD44 may predict poor survival and higher potential of metastasis in patients with osteosarcoma. The expression of CD44 in highly metastatic human osteosarcoma cell lines was efficiently blocked by CRISPR-Cas9. When CD44 was silenced, the proliferation and spheroid formation of these osteosarcoma cells was inhibited under 3-D culture conditions. Furthermore, the migratory and invasive functions were also impaired in these highly metastatic osteosarcoma cells. Conclusion: These results suggest that developing new strategies to target CD44 in osteosarcoma may prevent metastasis and improve the clinical outcome of osteosarcoma patients.

CD44 plays a functional role in Helicobacter pylori-induced epithelial cell proliferation.

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Nina Bertaux-Skeirik

2015-02-01

Full Text Available The cytotoxin-associated gene (Cag pathogenicity island is a strain-specific constituent of Helicobacter pylori (H. pylori that augments cancer risk. CagA translocates into the cytoplasm where it stimulates cell signaling through the interaction with tyrosine kinase c-Met receptor, leading cellular proliferation. Identified as a potential gastric stem cell marker, cluster-of-differentiation (CD CD44 also acts as a co-receptor for c-Met, but whether it plays a functional role in H. pylori-induced epithelial proliferation is unknown. We tested the hypothesis that CD44 plays a functional role in H. pylori-induced epithelial cell proliferation. To assay changes in gastric epithelial cell proliferation in relation to the direct interaction with H. pylori, human- and mouse-derived gastric organoids were infected with the G27 H. pylori strain or a mutant G27 strain bearing cagA deletion (∆CagA::cat. Epithelial proliferation was quantified by EdU immunostaining. Phosphorylation of c-Met was analyzed by immunoprecipitation followed by Western blot analysis for expression of CD44 and CagA. H. pylori infection of both mouse- and human-derived gastric organoids induced epithelial proliferation that correlated with c-Met phosphorylation. CagA and CD44 co-immunoprecipitated with phosphorylated c-Met. The formation of this complex did not occur in organoids infected with ∆CagA::cat. Epithelial proliferation in response to H. pylori infection was lost in infected organoids derived from CD44-deficient mouse stomachs. Human-derived fundic gastric organoids exhibited an induction in proliferation when infected with H. pylori that was not seen in organoids pre-treated with a peptide inhibitor specific to CD44. In the well-established Mongolian gerbil model of gastric cancer, animals treated with CD44 peptide inhibitor Pep1, resulted in the inhibition of H. pylori-induced proliferation and associated atrophic gastritis. The current study reports a unique

Cleavage of Hyaluronan and CD44 Adhesion Molecule Regulate Astrocyte Morphology via Rac1 Signalling.

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Anna Konopka

Full Text Available Communication of cells with their extracellular environment is crucial to fulfill their function in physiological and pathophysiological conditions. The literature data provide evidence that such a communication is also important in case of astrocytes. Mechanisms that contribute to the interaction between astrocytes and extracellular matrix (ECM proteins are still poorly understood. Hyaluronan is the main component of ECM in the brain, where its major receptor protein CD44 is expressed by a subset of astrocytes. Considering the fact that functions of astrocytes are tightly coupled with changes in their morphology (e.g.: glutamate clearance in the synaptic cleft, migration, astrogliosis, we investigated the influence of hyaluronan cleavage by hyaluronidase, knockdown of CD44 by specific shRNA and CD44 overexpression on astrocyte morphology. Our results show that hyaluronidase treatment, as well as knockdown of CD44, in astrocytes result in a "stellate"-like morphology, whereas overexpression of CD44 causes an increase in cell body size and changes the shape of astrocytes into flattened cells. Moreover, as a dynamic reorganization of the actin cytoskeleton is supposed to be responsible for morphological changes of cells, and this reorganization is controlled by small GTPases of the Rho family, we hypothesized that GTPase Rac1 acts as a downstream effector for hyaluronan and CD44 in astrocytes. We used FRET-based biosensor and a dominant negative mutant of Rac1 to investigate the involvement of Rac1 activity in hyaluronidase- and CD44-dependent morphological changes of astrocytes. Both, hyaluronidase treatment and knockdown of CD44, enhances Rac1 activity while overexpression of CD44 reduces the activity state in astrocytes. Furthermore, morphological changes were blocked by specific inhibition of Rac1 activity. These findings indicate for the first time that regulation of Rac1 activity is responsible for hyaluronidase and CD44-driven morphological

Cleavage of Hyaluronan and CD44 Adhesion Molecule Regulate Astrocyte Morphology via Rac1 Signalling.

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Konopka, Anna; Zeug, Andre; Skupien, Anna; Kaza, Beata; Mueller, Franziska; Chwedorowicz, Agnieszka; Ponimaskin, Evgeni; Wilczynski, Grzegorz M; Dzwonek, Joanna

2016-01-01

Communication of cells with their extracellular environment is crucial to fulfill their function in physiological and pathophysiological conditions. The literature data provide evidence that such a communication is also important in case of astrocytes. Mechanisms that contribute to the interaction between astrocytes and extracellular matrix (ECM) proteins are still poorly understood. Hyaluronan is the main component of ECM in the brain, where its major receptor protein CD44 is expressed by a subset of astrocytes. Considering the fact that functions of astrocytes are tightly coupled with changes in their morphology (e.g.: glutamate clearance in the synaptic cleft, migration, astrogliosis), we investigated the influence of hyaluronan cleavage by hyaluronidase, knockdown of CD44 by specific shRNA and CD44 overexpression on astrocyte morphology. Our results show that hyaluronidase treatment, as well as knockdown of CD44, in astrocytes result in a "stellate"-like morphology, whereas overexpression of CD44 causes an increase in cell body size and changes the shape of astrocytes into flattened cells. Moreover, as a dynamic reorganization of the actin cytoskeleton is supposed to be responsible for morphological changes of cells, and this reorganization is controlled by small GTPases of the Rho family, we hypothesized that GTPase Rac1 acts as a downstream effector for hyaluronan and CD44 in astrocytes. We used FRET-based biosensor and a dominant negative mutant of Rac1 to investigate the involvement of Rac1 activity in hyaluronidase- and CD44-dependent morphological changes of astrocytes. Both, hyaluronidase treatment and knockdown of CD44, enhances Rac1 activity while overexpression of CD44 reduces the activity state in astrocytes. Furthermore, morphological changes were blocked by specific inhibition of Rac1 activity. These findings indicate for the first time that regulation of Rac1 activity is responsible for hyaluronidase and CD44-driven morphological changes of

CD44 expression in IgA nephropathy

NARCIS (Netherlands)

Florquin, Sandrine; Nunziata, Raffaele; Claessen, Nike; van den Berg, Frank M.; Pals, Steven T.; Weening, Jan J.

2002-01-01

Immunoglobulin A (IgA) nephropathy is a frequent, chronic renal disease characterized by a broad spectrum of clinical presentations and pathologic findings. CD44, a family of type I transmembrane glycoproteins: involved in cell-cell and cell-matrix interactions, may orchestrate partially the cascade

Atomistic fingerprint of hyaluronan-CD44 binding

DEFF Research Database (Denmark)

Vuorio, Joni; Vattulainen, Ilpo; Martinez-Seara, Hector

2017-01-01

that hyaluronan can bind CD44 with three topographically different binding modes that in unison define an interaction fingerprint, thus providing a plausible explanation for the disagreement between the earlier studies. Our results confirm that the known crystallographic mode is the strongest of the three binding...

Lung cancer tumorigenicity and drug resistance are maintained through ALDH(hi)CD44(hi) tumor initiating cells.

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Liu, Jing; Xiao, Zhijie; Wong, Sunny Kit-Man; Tin, Vicky Pui-Chi; Ho, Ka-Yan; Wang, Junwen; Sham, Mai-Har; Wong, Maria Pik

2013-10-01

Limited improvement in long term survival of lung cancer patients has been achieved by conventional chemotherapy or targeted therapy. To explore the potentials of tumor initiating cells (TIC)-directed therapy, it is essential to identify the cell targets and understand their maintenance mechanisms. We have analyzed the performance of ALDH/CD44 co-expression as TIC markers and treatment targets of lung cancer using well-validated in vitro and in vivo analyses in multiple established and patient-derived lung cancer cells. The ALDH(hi)CD44(hi) subset showed the highest enhancement of stem cell phenotypic properties compared to ALDH(hi)CD44(lo), ALDH(lo)CD44(hi), ALDH(lo)CD44(lo) cells and unsorted controls. They showed higher invasion capacities, pluripotency genes and epithelial-mesenchymal transition transcription factors expression, lower intercellular adhesion protein expression and higher G2/M phase cell cycle fraction. In immunosuppressed mice, the ALDH(hi)CD44(hi)xenografts showed the highest tumor induction frequency, serial transplantability, shortest latency, largest volume and highest growth rates. Inhibition of sonic Hedgehog and Notch developmental pathways reduced ALDH+CD44+ compartment. Chemotherapy and targeted therapy resulted in higher AALDH(hi)CD44(hi) subset viability and ALDH(lo)CD44(lo) subset apoptosis fraction. ALDH inhibition and CD44 knockdown led to reduced stemness gene expression and sensitization to drug treatment. In accordance, clinical lung cancers containing a higher abundance of ALDH and CD44-coexpressing cells was associated with lower recurrence-free survival. Together, results suggested theALDH(hi)CD44(hi)compartment was the cellular mediator of tumorigenicity and drug resistance. Further investigation of the regulatory mechanisms underlying ALDH(hi)CD44(hi)TIC maintenance would be beneficial for the development of long term lung cancer control.

Tetraspanin CD9 regulates osteoclastogenesis via regulation of p44/42 MAPK activity

International Nuclear Information System (INIS)

Yi, TacGhee; Kim, Hye-Jin; Cho, Je-Yoel; Woo, Kyung Mi; Ryoo, Hyun-Mo; Kim, Gwan-Shik; Baek, Jeong-Hwa

2006-01-01

Tetraspanin CD9 has been shown to regulate cell-cell fusion in sperm-egg fusion and myotube formation. However, the role of CD9 in osteoclast, another multinucleated cell type, is not still clear. Therefore, we investigated the role of CD9 in osteoclast differentiation. CD9 was expressed in osteoclast lineage cells and its expression level increased during the progression of RANKL-induced osteoclastogenesis. KMC8, a neutralizing antibody specific to CD9, significantly suppressed RANKL-induced multinucleated osteoclast formation and the mRNA expression of osteoclast differentiation marker genes. To define CD9-regulated osteoclastogenic signaling pathway, MAPK pathways were examined. KMC8 induced long-term phosphorylation of p44/42 MAPK, but not of p38 MAPK. Constitutive activation of p44/42 MAPK by overexpressing constitutive-active mutant of MEK1 almost completely blocked osteoclast differentiation. Taken together, these results suggest that CD9 expressed on osteoclast lineage cells might positively regulate osteoclastogenesis via the regulation of p44/42 MAPK activity

Kaempferol regulates OPN–CD44 pathway to inhibit the atherogenesis of apolipoprotein E deficient mice

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Xiao, Hong-Bo; Lu, Xiang-Yang; Sun, Zhi-Liang; Zhang, Heng-Bo

2011-01-01

Recent studies show that osteopontin (OPN) and its receptor cluster of differentiation 44 (CD44) are two pro-inflammatory cytokines contributing to the development of atherosclerosis. The objective of this study was to explore the inhibitory effect of kaempferol, a naturally occurring flavonoid compound, on atherogenesis and the mechanisms involved. The experiments were performed in aorta and plasma from C57BL/6J control and apolipoprotein E-deficient (ApoE −/− ) mice treated or not with kaempferol (50 or 100 mg/kg, intragastrically) for 4 weeks. Kaempferol treatment decreased atherosclerotic lesion area, improved endothelium-dependent vasorelaxation, and increased the maximal relaxation value concomitantly with decrease in the half-maximum effective concentration, plasma OPN level, aortic OPN expression, and aortic CD44 expression in ApoE −/− mice. In addition, treatment with kaempferol also significantly decreased reactive oxygen species production in mice aorta. The present results suggest that kaempferol regulates OPN–CD44 pathway to inhibit the atherogenesis of ApoE −/− mice. -- Graphical abstract: Kaempferol regulates OPN–CD44 pathway to inhibit the atherogenesis of ApoE −/− mice. Highlights: ► OPN–CD44 pathway plays a critical role in the development of atherosclerosis. ► We examine lesion area, OPN and CD44 changes after kaempferol treatment. ► Kaempferol treatment decreased atherosclerotic lesion area in ApoE −/− mice. ► Kaempferol treatment decreased aortic OPN and CD44 expressions in ApoE −/− mice. ► Kaempferol regulates OPN–CD44 pathway to inhibit the atherogenesis.

Kaempferol regulates OPN-CD44 pathway to inhibit the atherogenesis of apolipoprotein E deficient mice

Energy Technology Data Exchange (ETDEWEB)

Xiao, Hong-Bo, E-mail: xhbzhb@yahoo.com [College of Veterinary Medicine, Hunan Agricultural University, Changsha 410128 (China); Lu, Xiang-Yang; Sun, Zhi-Liang [Hunan Agricultural University, Changsha 410128 (China); Zhang, Heng-Bo [Furong District Red Cross Hospital, Changsha 410126 (China)

2011-12-15

Recent studies show that osteopontin (OPN) and its receptor cluster of differentiation 44 (CD44) are two pro-inflammatory cytokines contributing to the development of atherosclerosis. The objective of this study was to explore the inhibitory effect of kaempferol, a naturally occurring flavonoid compound, on atherogenesis and the mechanisms involved. The experiments were performed in aorta and plasma from C57BL/6J control and apolipoprotein E-deficient (ApoE{sup -/-}) mice treated or not with kaempferol (50 or 100 mg/kg, intragastrically) for 4 weeks. Kaempferol treatment decreased atherosclerotic lesion area, improved endothelium-dependent vasorelaxation, and increased the maximal relaxation value concomitantly with decrease in the half-maximum effective concentration, plasma OPN level, aortic OPN expression, and aortic CD44 expression in ApoE{sup -/-} mice. In addition, treatment with kaempferol also significantly decreased reactive oxygen species production in mice aorta. The present results suggest that kaempferol regulates OPN-CD44 pathway to inhibit the atherogenesis of ApoE{sup -/-} mice. -- Graphical abstract: Kaempferol regulates OPN-CD44 pathway to inhibit the atherogenesis of ApoE{sup -/-} mice. Highlights: Black-Right-Pointing-Pointer OPN-CD44 pathway plays a critical role in the development of atherosclerosis. Black-Right-Pointing-Pointer We examine lesion area, OPN and CD44 changes after kaempferol treatment. Black-Right-Pointing-Pointer Kaempferol treatment decreased atherosclerotic lesion area in ApoE{sup -/-} mice. Black-Right-Pointing-Pointer Kaempferol treatment decreased aortic OPN and CD44 expressions in ApoE{sup -/-} mice. Black-Right-Pointing-Pointer Kaempferol regulates OPN-CD44 pathway to inhibit the atherogenesis.

CD44 deficiency enhanced Streptococcus equi ssp. zooepidemicus dissemination and inflammation response in a mouse model.

Science.gov (United States)

Fu, Qiang; Xiao, Pingping; Chen, Yaosheng; Wei, Zigong; Liu, Xiaohong

2017-12-01

Streptococcus equi ssp. zooepidemicus (S. zooepidemicus) is responsible for peritonitis, septicemia, meningitis, arthritis and several other serious diseases in various species. Recent studies have demonstrated that CD44 is implicated in the process of host defense against pathogenic microorganisms. In the present study, the role of CD44 in the host response to S. zooepidemicus infection was investigated in a mouse model. Upon intraperitoneal infection with S. zooepidemicus, the expression of CD44 on the peritoneal exudate cells from wild-type (WT) mice was increased. CD44 deficiency accelerated mortality, which was accompanied by increased peritoneal bacterial growth and dissemination to distant body sites. CD44 knock-out (KO) mice showed enhanced early inflammatory cell recruitment into the peritoneal fluid on S. zooepidemicus infection. In line with this, the expression of proinflammatory cytokines, chemokines in peritoneal exudate cells and peritoneal macrophages of CD44 KO mice were increased compared with those of WT mice. In addition, CD44 deficiency was associated with reduced expression of A20, a negative regulator in TLR signaling. Overall, the present study suggests that CD44 plays a protective role in antibacterial defense against S. zooepidemicus in mice. Copyright © 2017. Published by Elsevier Ltd.

Identification of a novel splice variant of human PD-L1 mRNA encoding an isoform-lacking Igv-like domain.

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He, Xian-hui; Xu, Li-hui; Liu, Yi

2005-04-01

To investigate the expression and regulation of PD-1 ligand 1 (PD-L1) in peripheral blood mononuclear cells (PBMC). The cDNA encoding human PD-L1 precursor was cloned from the total RNA extracted from the resting and phorbol dibutyrate plus ionomycin- or phytohemagglutinin-activated PBMC, by reverse transcription polymerase chain reaction (RT-PCR), and independent clones were sequenced and analyzed. The expression and subcellular localization were examined in transiently transfected cells. The PD-L1 gene expression in different PBMC was also analyzed by RT-PCR. A novel human PD-L1 splice variant was identified from the activated PBMC. It was generated by splicing out exon? encoding an immunoglobulin variable domain (Igv)-like domain but retaining all other exons without a frame-shift. Consequently, the putative translated protein contained all other domains including the transmembrane region except for the Igv-like domain. Furthermore, the conventional isoform was expressed on the plasma surface whereas the novel isoform showed a pattern of intracellular membrane distribution in transiently transfected K562 cells. In addition, the expression pattern of the PD-L1 splice variant was variable in different individuals and in different cellular status. PD-L1 expression may be regulated at the posttranscriptional level through alternative splicing, and modulation of the PD-L1 isoform expression may influence the outcome of specific immune responses in the peripheral tissues.

Hyaluronan functionalizing QDs as turn-on fluorescent probe for targeted recognition CD44 receptor

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Zhou, Shang; Huo, Danqun; Hou, Changjun; Yang, Mei; Fa, Huanbao

2017-09-01

The recognition of tumor markers in living cancer cells has attracted increasing interest. In the present study, the turn-on fluorescence probe was designed based on the fluorescence of thiolated chitosan-coated CdTe QDs (CdTe/TCS QDs) quenched by hyaluronan, which could provide the low background signal for sensitive cellular imaging. This system is expected to offer specific recognition of CD44 receptor over other substances owing to the specific affinity of hyaluronan and CD44 receptor ( 8-9 kcal/mol). The probe is stable in aqueous and has little toxicity to living cells; thus, it can be utilized for targeted cancer cell imaging. The living lung cancer cell imaging experiments further demonstrate its value in recognizing cell-surface CD44 receptor with turn-on mode. In addition, the probe can be used to recognize and differentiate the subtypes of lung cancer cells based on the difference of CD44 expression on the surface of lung cancer cells. And, the western blot test further confirmed that the expression level of the CD44 receptor in lung cancer cells is different. Therefore, this probe may be potentially applied in recognizing lung cancer cells with higher contrast and sensitivity and provide new tools for cancer prognosis and therapy. [Figure not available: see fulltext.

CD44 Interacts with HIF-2α to Modulate the Hypoxic Phenotype of Perinecrotic and Perivascular Glioma Cells

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Johansson, Elinn; Grassi, Elisa S.; Pantazopoulou, Vasiliki

2017-01-01

Hypoxia-inducible factors enhance glioma stemness, and glioma stem cells have an amplified hypoxic response despite residing within a perivascular niche. Still, little is known about differential HIF regulation in stem versus bulk glioma cells. We show that the intracellular domain of stem cell...... marker CD44 (CD44ICD) is released at hypoxia, binds HIF-2α (but not HIF-1α), enhances HIF target gene activation, and is required for hypoxia-induced stemness in glioma. In a glioma mouse model, CD44 was restricted to hypoxic and perivascular tumor regions, and in human glioma, a hypoxia signature...... correlated with CD44. The CD44ICD was sufficient to induce hypoxic signaling at perivascular oxygen tensions, and blocking CD44 cleavage decreased HIF-2α stabilization in CD44-expressing cells. Our data indicate that the stem cell marker CD44 modulates the hypoxic response of glioma cells and that the pseudo-hypoxic...

Exosomes Promote Ovarian Cancer Cell Invasion through Transfer of CD44 to Peritoneal Mesothelial Cells.

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Nakamura, Koji; Sawada, Kenjiro; Kinose, Yasuto; Yoshimura, Akihiko; Toda, Aska; Nakatsuka, Erika; Hashimoto, Kae; Mabuchi, Seiji; Morishige, Ken-Ichirou; Kurachi, Hirohisa; Lengyel, Ernst; Kimura, Tadashi

2017-01-01

Epithelial ovarian cancer (EOC) cells metastasize within the peritoneal cavity and directly encounter human peritoneal mesothelial cells (HPMC) as the initial step of metastasis. The contact between ovarian cancer cells and the single layer of mesothelial cells involves direct communications that modulate cancer progression but the mechanisms are unclear. One candidate mediating cell-cell communications is exosomes, 30-100 nm membrane vesicles of endocytic origin, through the cell-cell transfer of proteins, mRNAs, or microRNAs. Therefore, the goal was to mechanistically characterize how EOC-derived exosomes modulate metastasis. Exosomes from ovarian cancer cells were fluorescently labeled and cocultured with HPMCs which internalized the exosomes. Upon exosome uptake, HPMCs underwent a change in cellular morphology to a mesenchymal, spindle phenotype. CD44, a cell surface glycoprotein, was found to be enriched in the cancer cell-derived exosomes, transferred, and internalized to HPMCs, leading to high levels of CD44 in HPMCs. This increased CD44 expression in HPMCs promoted cancer invasion by inducing the HPMCs to secrete MMP9 and by cleaning the mesothelial barrier for improved cancer cell invasion. When CD44 expression was knocked down in cancer cells, exosomes had fewer effects on HPMCs. The inhibition of exosome release from cancer cells blocked CD44 internalization in HPMCs and suppressed ovarian cancer invasion. In ovarian cancer omental metastasis, positive CD44 expression was observed in those mesothelial cells that directly interacted with cancer cells, whereas CD44 expression was negative in the mesothelial cells remote from the invading edge. This study indicates that ovarian cancer-derived exosomes transfer CD44 to HPMCs, facilitating cancer invasion. Mechanistic insight from the current study suggests that therapeutic targeting of exosomes may be beneficial in treating ovarian cancer. Mol Cancer Res; 15(1); 78-92. ©2016 AACR. ©2016 American

Effects of CD44 Ligation on Signaling and Metabolic Pathways in Acute Myeloid Leukemia

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Madhoun, Nour Y.

2017-01-01

Acute myeloid leukemia (AML) is characterized by a blockage in the differentiation of myeloid cells at different stages. CD44-ligation using anti-CD44 monoclonal antibodies (mAbs) has been shown to reverse the blockage of differentiation

Conformational and functional variants of CD44-targeted protein nanoparticles bio-produced in bacteria

International Nuclear Information System (INIS)

Pesarrodona, Mireia; Conchillo-Solé, Oscar; Unzueta, Ugutz; Xu, Zhikun; Ferrer-Miralles, Neus; Daura, Xavier; Vázquez, Esther; Villaverde, Antonio; Fernández, Yolanda; Foradada, Laia; Schwartz, Simó Jr; Abasolo, Ibane; Sánchez-Chardi, Alejandro; Roldán, Mónica; Villegas, Sandra; Rinas, Ursula

2016-01-01

Biofabrication is attracting interest as a means to produce nanostructured functional materials because of its operational versatility and full scalability. Materials based on proteins are especially appealing, as the structure and functionality of proteins can be adapted by genetic engineering. Furthermore, strategies and tools for protein production have been developed and refined steadily for more than 30 years. However, protein conformation and therefore activity might be sensitive to production conditions. Here, we have explored whether the downstream strategy influences the structure and biological activities, in vitro and in vivo, of a self-assembling, CD44-targeted protein-only nanoparticle produced in Escherichia coli. This has been performed through the comparative analysis of particles built from soluble protein species or protein versions obtained by in vitro protein extraction from inclusion bodies, through mild, non-denaturing procedures. These methods have been developed recently as a convenient alternative to the use of toxic chaotropic agents for protein resolubilization from protein aggregates. The results indicate that the resulting material shows substantial differences in its physicochemical properties and its biological performance at the systems level, and that its building blocks are sensitive to the particular protein source. (paper)

Different associations of CD45 isoforms with STAT3, PKC and ERK regulate IL-6-induced proliferation in myeloma.

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Xu Zheng

Full Text Available In response to interleukin 6 (IL-6 stimulation, both CD45RO and CD45RB, but not CD45RA, translocate to lipid rafts. However, the significance of this distinct translocation and the downstream signals in CD45 isoforms-participated IL-6 signal are not well understood. Using sucrose fractionation, we found that phosphorylated signal transducer and activator of transcription (STAT3 and STAT1 were mainly localized in lipid rafts in response to IL-6 stimulation, despite both STAT3 and STAT1 localizing in raft and non-raft fractions in the presence or absence of IL-6. On the other hand, extracellular signal-regulated kinase (ERK, and phosphorylated ERK were localized in non-raft fractions regardless of the existence of IL-6. The rafts inhibitor significantly impeded the phosphorylation of STAT3 and STAT1 and nuclear translocation, but had little effect on (and only postponing the phosphorylation of ERK. This data suggests that lipid raft-dependent STAT3 and STAT1 pathways are dominant pathways of IL-6 signal in myeloma cells. Interestingly, the phosphorylation level of STAT3 but not STAT1 in CD45+ cells was significantly higher compared to that of CD45- cells, while the phosphorylation level of ERK in CD45+ myeloma cells was relatively low. Furthermore, exogenously expressed CD45RO/RB significantly enhanced STAT3, protein kinase C (PKC and downstream NF-κB activation; however, CD45RA/RB inhibited IL-6-induced ERK phosphorylation. CD45 also enhanced the nuclear localization of STAT3 but not that of STAT1. In response to IL-6 stimulation, CD45RO moved into raft compartments and formed a complex with STAT3 and PKC in raft fraction, while CD45RA remained outside of lipid rafts and formed a complex with ERK in non-raft fraction. This data suggests a different role of CD45 isoforms in IL-6-induced signaling, indicating that while CD45RA/RB seems inhibit the rafts-unrelated ERK pathway, CD45RO/RB may actually work to enhance the rafts-related STAT3 and PKC

CD44-positive cells are candidates for astrocyte precursor cells in developing mouse cerebellum.

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Cai, Na; Kurachi, Masashi; Shibasaki, Koji; Okano-Uchida, Takayuki; Ishizaki, Yasuki

2012-03-01

Neural stem cells are generally considered to be committed to becoming precursor cells before terminally differentiating into either neurons or glial cells during neural development. Neuronal and oligodendrocyte precursor cells have been identified in several areas in the murine central nervous system. The presence of astrocyte precursor cells (APCs) is not so well understood. The present study provides several lines of evidence that CD44-positive cells are APCs in the early postnatal mouse cerebellum. In developing mouse cerebellum, CD44-positive cells, mostly located in the white matter, were positive for the markers of the astrocyte lineage, but negative for the markers of mature astrocytes. CD44-positive cells were purified from postnatal cerebellum by fluorescence-activated cell sorting and characterized in vitro. In the absence of any signaling molecule, many cells died by apoptosis. The surviving cells gradually expressed glial fibrillary acidic protein, a marker for mature astrocytes, indicating that differentiation into mature astrocytes is the default program for these cells. The cells produced no neurospheres nor neurons nor oligodendrocytes under any condition examined, indicating these cells are not neural stem cells. Leukemia inhibitory factor greatly promoted astrocytic differentiation of CD44-positive cells, whereas bone morphogenetic protein 4 (BMP4) did not. Fibroblast growth factor-2 was a potent mitogen for these cells, but was insufficient for survival. BMP4 inhibited activation of caspase-3 and greatly promoted survival, suggesting a novel role for BMP4 in the control of development of astrocytes in cerebellum. We isolated and characterized only CD44 strongly positive large cells and discarded small and/or CD44 weakly positive cells in this study. Further studies are necessary to characterize these cells to help determine whether CD44 is a selective and specific marker for APCs in the developing mouse cerebellum. In conclusion, we succeeded in

Expression of CD44 and P53 in renal cell carcinoma: Association with tumor subtypes

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Farahnaz Noroozinia

2014-01-01

Full Text Available Renal cell carcinoma (RCC is a common malignancy of the kidney and accurate prediction of prognosis is valuable for the design of adjuvant therapy and counseling and effective scheduling of follow-up visits. Molecular genetic investigations of CD44 and P53 in RCC may be helpful in this regard. We studied the CD44 and P53 expressions semi-quantitatively on paraffin-embedded specimens of 64 RCC patients (37 male/27 female who underwent surgery from 2003 to 2008 by immunohistochemistry and analyzed the correlation of P53 and CD44 expression in RCC and outcome. Thirteen of 64 (20.3% specimens were P53 positive, 30/64 (46.9% were CD44 positive and five tumors with positive P53 expressed CD44 protein (P = 0.5. A statistically significant correlation was not found between CD44 and P53 expression (P = 0.5 and age (P = 0.07, sex (P= 0.3, tumor size (P = 0.7, grade (P = 0.23, vascular invasion (P = 1.00 and ureteral invasion (P = 1.00. Furthermore, a significant correlation was not found between P53 expression with age (P = 0.3, sex (P = 0.7, tumor size (P = 0.7, grade (P = 0.1, vascular inva-sion (P = 1.00 and ureteral invasion (P = 1.00. According to our findings, only P53 expression is generally accompanied by non-conventional subtype tumor.

Expression of CD44 3'-untranslated region regulates endogenous microRNA functions in tumorigenesis and angiogenesis.

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Jeyapalan, Zina; Deng, Zhaoqun; Shatseva, Tatiana; Fang, Ling; He, Chengyan; Yang, Burton B

2011-04-01

The non-coding 3'-untranslated region (UTR) plays an important role in the regulation of microRNA (miRNA) functions, since it can bind and inactivate multiple miRNAs. Here, we show the 3'-UTR of CD44 is able to antagonize cytoplasmic miRNAs, and result in the increased translation of CD44 and downstream target mRNA, CDC42. A series of cell function assays in the human breast cancer cell line, MT-1, have shown that the CD44 3'-UTR inhibits proliferation, colony formation and tumor growth. Furthermore, it modulated endothelial cell activities, favored angiogenesis, induced tumor cell apoptosis and increased sensitivity to Docetaxel. These results are due to the interaction of the CD44 3'-UTR with multiple miRNAs. Computational algorithms have predicted three miRNAs, miR-216a, miR-330 and miR-608, can bind to both the CD44 and CDC42 3'-UTRs. This was confirmed with luciferase assays, western blotting and immunohistochemical staining and correlated with a series of siRNA assays. Thus, the non-coding CD44 3'-UTR serves as a competitor for miRNA binding and subsequently inactivates miRNA functions, by freeing the target mRNAs from being repressed.

Suppression of human breast tumors in NOD/SCID mice by CD44 shRNA gene therapy combined with doxorubicin treatment

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Pham PV

2012-05-01

Full Text Available Phuc Van Pham1, Ngoc Bich Vu1, Thuy Thanh Duong1, Tam Thanh Nguyen1, Nhung Hai Truong1, Nhan Lu Chinh Phan1, Tue Gia Vuong1, Viet Quoc Pham1, Hoang Minh Nguyen1, Kha The Nguyen1, Nhung Thi Nguyen1, Khue Gia Nguyen1, Lam Tan Khat1, Dong Van Le2, Kiet Dinh Truong1, Ngoc Kim Phan11Laboratory of Stem Cell Research and Application, University of Science, Vietnam National University, HCM City, 2Military Medical University, Ha Noi, VietnamBackground: Breast cancer stem cells with a CD44+CD24- phenotype are the origin of breast tumors. Strong CD44 expression in this population indicates its important role in maintaining the stem cell phenotype. Previous studies show that CD44 down-regulation causes CD44+CD24- breast cancer stem cells to differentiate into non-stem cells that are sensitive to antitumor drugs and lose many characteristics of the original cells. In this study, we determined tumor suppression in non-obese severe combined immunodeficiency mice using CD44 shRNA therapy combined with doxorubicin treatment.Methods: Tumor-bearing non-obese severe combined immunodeficiency mice were established by injection of CD44+CD24- cells. To track CD44+CD24- cells, green fluorescence protein was stably transduced using a lentiviral vector prior to injection into mice. The amount of CD44 shRNA lentiviral vector used for transduction was based on CD44 down-regulation by in vitro CD44 shRNA transduction. Mice were treated with direct injection of CD44 shRNA lentiviral vector into tumors followed by doxorubicin administration after 48 hours. The effect was evaluated by changes in the size and weight of tumors compared with that of the control.Results: The combination of CD44 down-regulation and doxorubicin strongly suppressed tumor growth with significant differences in tumor sizes and weights compared with that of CD44 down-regulation or doxorubicin treatment alone. In the combination of CD44 down-regulation and doxorubicin group, the tumor weight was

Tartrate-resistant acid phosphatase (TRAP/ACP5) promotes metastasis-related properties via TGFβ2/TβR and CD44 in MDA-MB-231 breast cancer cells.

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Reithmeier, Anja; Panizza, Elena; Krumpel, Michael; Orre, Lukas M; Branca, Rui M M; Lehtiö, Janne; Ek-Rylander, Barbro; Andersson, Göran

2017-09-15

Tartrate-resistant acid phosphatase (TRAP/ACP5), a metalloenzyme that is characteristic for its expression in activated osteoclasts and in macrophages, has recently gained considerable focus as a driver of metastasis and was associated with clinically relevant parameters of cancer progression and cancer aggressiveness. MDA-MB-231 breast cancer cells with different TRAP expression levels (overexpression and knockdown) were generated and characterized for protein expression and activity levels. Functional cell experiments, such as proliferation, migration and invasion assays were performed as well as global phosphoproteomic and proteomic analysis was conducted to connect molecular perturbations to the phenotypic changes. We identified an association between metastasis-related properties of TRAP-overexpressing MDA-MB-231 breast cancer cells and a TRAP-dependent regulation of Transforming growth factor (TGFβ) pathway proteins and Cluster of differentiation 44 (CD44). Overexpression of TRAP increased anchorage-independent and anchorage-dependent cell growth and proliferation, induced a more elongated cellular morphology and promoted cell migration and invasion. Migration was increased in the presence of the extracellular matrix (ECM) proteins osteopontin and fibronectin and the basement membrane proteins collagen IV and laminin I. TRAP-induced properties were reverted upon shRNA-mediated knockdown of TRAP or treatment with the small molecule TRAP inhibitor 5-PNA. Global phosphoproteomics and proteomics analyses identified possible substrates of TRAP phosphatase activity or signaling intermediates and outlined a TRAP-dependent regulation of proteins involved in cell adhesion and ECM organization. Upregulation of TGFβ isoform 2 (TGFβ2), TGFβ receptor type 1 (TβR1) and Mothers against decapentaplegic homolog 2 (SMAD2), as well as increased intracellular phosphorylation of CD44 were identified upon TRAP perturbation. Functional antibody-mediated blocking and chemical

Non-secreted clusterin isoforms are translated in rare amounts from distinct human mRNA variants and do not affect Bax-mediated apoptosis or the NF-κB signaling pathway.

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Hans Prochnow

Full Text Available Clusterin, also known as apolipoprotein J, is expressed from a variety of tissues and implicated in pathological disorders such as neurodegenerative diseases, ischemia and cancer. In contrast to secretory clusterin (sCLU, which acts as an extracellular chaperone, the synthesis, subcellular localization and function(s of intracellular CLU isoforms is currently a matter of intense discussion. By investigating human CLU mRNAs we here unravel mechanisms leading to the synthesis of distinct CLU protein isoforms and analyze their subcellular localization and their impact on apoptosis and on NF-κB-activity. Quantitative PCR-analyses revealed the expression of four different stress-inducible CLU mRNA variants in non-cancer and cancer cell lines. In all cell lines variant 1 represents the most abundant mRNA, whereas all other variants collectively account for no more than 0.34% of total CLU mRNA, even under stressed conditions. Overexpression of CLU cDNAs combined with in vitro mutagenesis revealed distinct translational start sites including a so far uncharacterized non-canonical CUG start codon. We show that all exon 2-containing mRNAs encode sCLU and at least three non-glycosylated intracellular isoforms, CLU1‑449, CLU21‑449 and CLU34‑449, which all reside in the cytosol of unstressed and stressed HEK‑293 cells. The latter is the only form expressed from an alternatively spliced mRNA variant lacking exon 2. Functional analysis revealed that none of these cytosolic CLU forms modulate caspase-mediated intrinsic apoptosis or significantly affects TNF-α-induced NF-κB-activity. Therefore our data challenge some of the current ideas regarding the physiological functions of CLU isoforms in pathologies.

Transforming growth factor-β-mediated CD44/STAT3 signaling contributes to the development of atrial fibrosis and fibrillation.

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Chang, Shang-Hung; Yeh, Yung-Hsin; Lee, Jia-Lin; Hsu, Yu-Juei; Kuo, Chi-Tai; Chen, Wei-Jan

2017-09-04

Atrial fibrillation (AF) is associated with atrial fibrosis. Inhibition of atrial fibrosis might be a plausible approach for AF prevention and therapy. This study is designed to evaluate the potential role of CD44, a membrane receptor known to regulate fibrosis, and its related signaling in the pathogenesis of atrial fibrosis and AF. Treatment of cultured rat atrial fibroblasts with transforming growth factor-β (TGF-β, a key mediator of atrial fibrosis) led to a higher expression of hyaluronan (HA), CD44, STAT3, and collagen (a principal marker of fibrosis) than that of ventricular fibroblasts. In vivo, TGF-β transgenic mice and AF patients exhibited a greater expression of HA, CD44, STAT3, and collagen in their atria than wild-type mice and sinus rhythm subjects, respectively. Treating TGF-β transgenic mice with an anti-CD44 blocking antibody resulted in a lower expression of STAT3 and collagen in their atria than those with control IgG antibody. Programmed stimulation triggered less AF episodes in TGF-β transgenic mice treated with anti-CD44 blocking antibody than in those with control IgG. Blocking CD44 signaling with anti-CD44 antibody and mutated CD44 plasmids attenuated TGF-β-induced STAT3 activation and collagen expression in cultured atrial fibroblasts. Deletion and mutational analysis of the collagen promoter along with chromatin immunoprecipitation demonstrated that STAT3 served as a vital transcription factor in collagen expression. TGF-β-mediated HA/CD44/STAT3 pathway plays a crucial role in the development of atrial fibrosis and AF. Blocking CD44-dependent signaling may be a feasible way for AF management.

CD44 Binding to Hyaluronic Acid Is Redox Regulated by a Labile Disulfide Bond in the Hyaluronic Acid Binding Site.

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Helena Kellett-Clarke

Full Text Available CD44 is the primary leukocyte cell surface receptor for hyaluronic acid (HA, a component of the extracellular matrix. Enzymatic post translational cleavage of labile disulfide bonds is a mechanism by which proteins are structurally regulated by imparting an allosteric change and altering activity. We have identified one such disulfide bond in CD44 formed by Cys77 and Cys97 that stabilises the HA binding groove. This bond is labile on the surface of leukocytes treated with chemical and enzymatic reducing agents. Analysis of CD44 crystal structures reveal the disulfide bond to be solvent accessible and in the-LH hook configuration characteristic of labile disulfide bonds. Kinetic trapping and binding experiments on CD44-Fc chimeric proteins show the bond is preferentially reduced over the other disulfide bonds in CD44 and reduction inhibits the CD44-HA interaction. Furthermore cells transfected with CD44 no longer adhere to HA coated surfaces after pre-treatment with reducing agents. The implications of CD44 redox regulation are discussed in the context of immune function, disease and therapeutic strategies.

Effects of CD44 and E-cadherin overexpression on the proliferation, adhesion and invasion of ovarian cancer cells.

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Mao, Meiya; Zheng, Xiaojiao; Jin, Bohong; Zhang, Fubin; Zhu, Linyan; Cui, Lining

2017-12-01

CD44 is a prognostic indicator of shorter survival time in ovarian cancer. E-cadherin fragmentation promotes the progression of ovarian cancer. However, the effects of CD44 and E-cadherin overexpression on ovarian cancer cells have remained elusive. The present study aimed to investigate the effects of overexpression of CD44 and E-cadherin on cell proliferation, adhesion and invasion of SKOV-3 and OVCAR-3 ovarian cancer cells. Overexpression of CD44 and E-cadherin was achieved by transfecting SKOV-3 and OVCAR-3 cells with viruses carrying the CD44 or E-cadherin gene, respectively. Expression of CD44 and E-cadherin was detected by western blot analysis. The proliferation of SKOV-3 and OVCAR-3 cells was measured by a Cell Counting Kit-8 at 0, 24 and 48 h after viral transfection. The adhesion ability of SKOV-3 and OVCAR-3 cells to the endothelial layer was detected. A Transwell invasion assay was utilized to assess the invasion ability of the cells. Overexpression of CD44 and E-cadherin in SKOV-3 and OVCAR-3 cells was confirmed by western blot. Compared with the blank or negative control groups, the CD44 overexpression groups of SKOV-3 and OVCAR-3 cells exhibited an increased cell proliferation rate at 24 and 48 h, whereas overexpression of E-cadherin did not alter the proliferation of these cells. Furthermore, compared with the blank and negative control groups, the cell adhesion and invasion ability in the CD44 overexpression groups of SKOV-3 and OVCAR-3 cells was markedly higher. There were no significant differences in adhesion ability between the E-cadherin overexpression group and the blank/negative control group. Of note, overexpression of E-cadherin decreased the invasive ability of SKOV-3 and OVCAR-3 cells. In conclusion, Overexpression of CD44 increased the proliferation, adhesion and invasion of ovarian cancer cells, while overexpression of E-cadherin decreased the invasion of ovarian cancer cells.

Assessing Specific Oligonucleotides and Small Molecule Antibiotics for the Ability to Inhibit the CRD-BP-CD44 RNA Interaction

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Thomsen, Dana; Lee, Chow H.

2014-01-01

Studies on Coding Region Determinant-Binding Protein (CRD-BP) and its orthologs have confirmed their functional role in mRNA stability and localization. CRD-BP is present in extremely low levels in normal adult tissues, but it is over-expressed in many types of aggressive human cancers and in neonatal tissues. Although the exact role of CRD-BP in tumour progression is unclear, cumulative evidence suggests that its ability to physically associate with target mRNAs is an important criterion for its oncogenic role. CRD-BP has high affinity for the 3′UTR of the oncogenic CD44 mRNA and depletion of CRD-BP in cells led to destabilization of CD44 mRNA, decreased CD44 expression, reduced adhesion and disruption of invadopodia formation. Here, we further characterize the CRD-BP-CD44 RNA interaction and assess specific antisense oligonucleotides and small molecule antibiotics for their ability to inhibit the CRD-BP-CD44 RNA interaction. CRD-BP has a high affinity for binding to CD44 RNA nts 2862–3055 with a Kd of 645 nM. Out of ten antisense oligonucleotides spanning nts 2862–3055, only three antisense oligonucleotides (DD4, DD7 and DD10) were effective in competing with CRD-BP for binding to 32P-labeled CD44 RNA. The potency of DD4, DD7 and DD10 in inhibiting the CRD-BP-CD44 RNA interaction in vitro correlated with their ability to specifically reduce the steady-state level of CD44 mRNA in cells. The aminoglycoside antibiotics neomycin, paramomycin, kanamycin and streptomycin effectively inhibited the CRD-BP-CD44 RNA interaction in vitro. Assessing the potential inhibitory effect of aminoglycoside antibiotics including neomycin on the CRD-BP-CD44 mRNA interaction in cells proved difficult, likely due to their propensity to non-specifically bind nucleic acids. Our results have important implications for future studies in finding small molecules and nucleic acid-based inhibitors that interfere with protein-RNA interactions. PMID:24622399

CD44+ cancer stem-like cells in EBV-associated nasopharyngeal carcinoma.

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Samantha Wei-Man Lun

Full Text Available Nasopharyngeal carcinoma (NPC is a unique EBV-associated epithelial malignancy, showing highly invasive and metastatic phenotype. Despite increasing evidence demonstrating the critical role of cancer stem-like cells (CSCs in the maintenance and progression of tumors in a variety of malignancies, the existence and properties of CSC in EBV-associated NPC are largely unknown. Our study aims to elucidate the presence and role of CSCs in the pathogenesis of this malignant disease. Sphere-forming cells were isolated from an EBV-positive NPC cell line C666-1 and its tumor-initiating properties were confirmed by in vitro and in vivo assays. In these spheroids, up-regulation of multiple stem cell markers were found. By flow cytometry, we demonstrated that both CD44 and SOX2 were overexpressed in a majority of sphere-forming C666-1 cells. The CD44+SOX2+ cells was detected in a minor population in EBV-positive xenografts and primary tumors and considered as potential CSC in NPC. Notably, the isolated CD44+ NPC cells were resistant to chemotherapeutic agents and with higher spheroid formation efficiency, showing CSC properties. On the other hand, microarray analysis has revealed a number of differentially expressed genes involved in transcription regulation (e.g. FOXN4, GLI1, immune response (CCR7, IL8 and transmembrane transport (e.g. ABCC3, ABCC11 in the spheroids. Among these genes, increased expression of CCR7 in CD44+ CSCs was confirmed in NPC xenografts and primary tumors. Importantly, blocking of CCR7 abolished the sphere-forming ability of C666-1 in vitro. Expression of CCR7 was associated with recurrent disease and distant metastasis. The current study defined the specific properties of a CSC subpopulation in EBV-associated NPC. Our findings provided new insights into developing effective therapies targeting on CSCs, thereby potentiating treatment efficacy for NPC patients.

CD44+ Cancer Stem-Like Cells in EBV-Associated Nasopharyngeal Carcinoma

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Lun, Samantha Wei-Man; Cheung, Siu Tim; Cheung, Phyllis Fung Yi; To, Ka-Fai; Woo, John Kong-Sang; Choy, Kwong-Wai; Chow, Chit; Cheung, Chartia Ching-Mei; Chung, Grace Tin-Yun; Cheng, Alice Suk-Hang; Ko, Chun-Wai; Tsao, Sai-Wah; Busson, Pierre; Ng, Margaret Heung-Ling; Lo, Kwok-Wai

2012-01-01

Nasopharyngeal carcinoma (NPC) is a unique EBV-associated epithelial malignancy, showing highly invasive and metastatic phenotype. Despite increasing evidence demonstrating the critical role of cancer stem-like cells (CSCs) in the maintenance and progression of tumors in a variety of malignancies, the existence and properties of CSC in EBV-associated NPC are largely unknown. Our study aims to elucidate the presence and role of CSCs in the pathogenesis of this malignant disease. Sphere-forming cells were isolated from an EBV-positive NPC cell line C666-1 and its tumor-initiating properties were confirmed by in vitro and in vivo assays. In these spheroids, up-regulation of multiple stem cell markers were found. By flow cytometry, we demonstrated that both CD44 and SOX2 were overexpressed in a majority of sphere-forming C666-1 cells. The CD44+SOX2+ cells was detected in a minor population in EBV-positive xenografts and primary tumors and considered as potential CSC in NPC. Notably, the isolated CD44+ NPC cells were resistant to chemotherapeutic agents and with higher spheroid formation efficiency, showing CSC properties. On the other hand, microarray analysis has revealed a number of differentially expressed genes involved in transcription regulation (e.g. FOXN4, GLI1), immune response (CCR7, IL8) and transmembrane transport (e.g. ABCC3, ABCC11) in the spheroids. Among these genes, increased expression of CCR7 in CD44+ CSCs was confirmed in NPC xenografts and primary tumors. Importantly, blocking of CCR7 abolished the sphere-forming ability of C666-1 in vitro. Expression of CCR7 was associated with recurrent disease and distant metastasis. The current study defined the specific properties of a CSC subpopulation in EBV-associated NPC. Our findings provided new insights into developing effective therapies targeting on CSCs, thereby potentiating treatment efficacy for NPC patients. PMID:23285037

Expression of CD44 3′-untranslated region regulates endogenous microRNA functions in tumorigenesis and angiogenesis

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Jeyapalan, Zina; Deng, Zhaoqun; Shatseva, Tatiana; Fang, Ling; He, Chengyan; Yang, Burton B.

2011-01-01

The non-coding 3′-untranslated region (UTR) plays an important role in the regulation of microRNA (miRNA) functions, since it can bind and inactivate multiple miRNAs. Here, we show the 3′-UTR of CD44 is able to antagonize cytoplasmic miRNAs, and result in the increased translation of CD44 and downstream target mRNA, CDC42. A series of cell function assays in the human breast cancer cell line, MT-1, have shown that the CD44 3′-UTR inhibits proliferation, colony formation and tumor growth. Furthermore, it modulated endothelial cell activities, favored angiogenesis, induced tumor cell apoptosis and increased sensitivity to Docetaxel. These results are due to the interaction of the CD44 3′-UTR with multiple miRNAs. Computational algorithms have predicted three miRNAs, miR-216a, miR-330 and miR-608, can bind to both the CD44 and CDC42 3′-UTRs. This was confirmed with luciferase assays, western blotting and immunohistochemical staining and correlated with a series of siRNA assays. Thus, the non-coding CD44 3′-UTR serves as a competitor for miRNA binding and subsequently inactivates miRNA functions, by freeing the target mRNAs from being repressed. PMID:21149267

The interaction between aromatase, metalloproteinase 2,9 and cd44 in breast cancer A interação entre aromatase, metalloproteinase 2, 9 e cd44 no câncer de mama

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Fábio Bagnoli

2010-01-01

Full Text Available OBJECTIVE: This study intends to verify the expression levels and correlation of aromatase, matrix metalloproteinase 2 (MMP-2, matrix metalloproteinase 9 (MMP-9 and CD44 in ductal carcinoma in situ (DCIS and infiltrating ductal carcinoma (IDC when both are found in the same breast. METHODS: One hundred and ten cases were evaluated by tissue microarray (TMA and immunohistochemically screened with anti-aromatase polyclonal antibodies, anti-MMP-2 monoclonal antibodies, anti-MMP-9 policlonal antibodies and anti-CD44 monoclonal antibodies. RESULTS: Aromatase was expressed in IDC and DCIS in 63 (57.3% and 60 (67% of the cases respectively; MMP-2 was similarly expressed in IDC and DCIS in 15 (13.60% cases; MMP-9 was positively expressed in IDC and DCIS in 83 (75.50% and 82 (74.50% cases, respectively; CD44 was positively expressed in IDC and DCIS in 49 (44.50% and 48 (42.60% of the cases, respectively; all of them were highly correlated (pOBJETIVO: O objetivo desse estudo é verificar as expressões e correlações da aromatase, metalloproteinase 2 da matriz (MMP2, metalloproteinase 9 da matriz (MMP-9 e CD44 no carcinoma ductal in situ (CDIS e carcinoma ductal infiltrativo (CDI quando ambos estão presentes simultaneamente na mesma mama. MÉTODOS: Foram avaliados 110 casos pelo método de tissue microarray (TMA e através da utilização de anticorpos policlonais antiaromatase, anticorpos monoclonais anti-MMP-2, anticorpos policlonais anti-MMP-9 e anticorpos monoclonais anti-CD44. RESULTADOS: A aromatase estava expressa de forma positiva no CDI e CDIS em 63 (57,3% e 60 (67% casos, respectivamente. A expressão de MMP-2 estava expressa de forma positiva em 15 (13,6% casos tanto no CDI, quanto no CDIS. A expressão da MMP-9 estava expressa de forma positiva em 83 (75,5% e 82 (74,5% casos de CDI e CDIS, respectivamente. A expressão de CD44 estava expressa de forma positiva em 49 (44,5% e 48 (42,6% casos de CDI e CDIS, respectivamente. Todos eles

A novel mechanism of regulating breast cancer cell migration via palmitoylation-dependent alterations in the lipid raft affiliation of CD44.

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Babina, Irina S; McSherry, Elaine A; Donatello, Simona; Hill, Arnold D K; Hopkins, Ann M

2014-02-10

Most breast cancer-related deaths result from metastasis, a process involving dynamic regulation of tumour cell adhesion and migration. The adhesion protein CD44, a key regulator of cell migration, is enriched in cholesterol-enriched membrane microdomains termed lipid rafts. We recently reported that raft affiliation of CD44 negatively regulates interactions with its migratory binding partner ezrin. Since raft affiliation is regulated by post-translational modifications including palmitoylation, we sought to establish the contribution of CD44 palmitoylation and lipid raft affiliation to cell migration. Recovery of CD44 and its binding partners from raft versus non-raft membrane microdomains was profiled in non-migrating and migrating breast cancer cell lines. Site-directed mutagenesis was used to introduce single or double point mutations into both CD44 palmitoylation sites (Cys286 and Cys295), whereupon the implications for lipid raft recovery, phenotype, ezrin co-precipitation and migratory behaviour was assessed. Finally CD44 palmitoylation status and lipid raft affiliation was assessed in primary cultures from a small panel of breast cancer patients. CD44 raft affiliation was increased during migration of non-invasive breast cell lines, but decreased during migration of highly-invasive breast cells. The latter was paralleled by increased CD44 recovery in non-raft fractions, and exclusive non-raft recovery of its binding partners. Point mutation of CD44 palmitoylation sites reduced CD44 raft affiliation in invasive MDA-MB-231 cells, increased CD44-ezrin co-precipitation and accordingly enhanced cell migration. Expression of palmitoylation-impaired (raft-excluded) CD44 mutants in non-invasive MCF-10a cells was sufficient to reversibly induce the phenotypic appearance of epithelial-to-mesenchymal transition and to increase cell motility. Interestingly, cell migration was associated with temporal reductions in CD44 palmitoylation in wild-type breast cells. Finally

High Expression of Osteopontin and CD44v6 in Odontogenic Keratocysts

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Yi-Ping Wang

2009-04-01

Conclusion: Binding of OPN to osteoclast cell membrane receptor integrin αv can activate the osteoclasts and increase their osteolytic activity. In addition, binding of OPN to OKC lining epithelial cell membrane receptor CD44v6 can enhance the motility, migration, invasion and spread of lining epithelial cells into the surrounding cancellous bone. Therefore, we suggest that the local aggressive behavior and high osteolytic ability of OKCs in the jawbone can be explained at least partially by high expression of OPN and CD44v6 in lining epithelial cells of OKCs and high expression of integrin αv in osteoclasts.

СD44+/CD24- markers of cancer stem cells in patients with breast cancer of different molecular subtypes.

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Chekhun, S V; Zadvorny, T V; Tymovska, Yu O; Anikusko, M F; Novak, O E; Polishchuk, L Z

2015-03-01

To determine frequency of tumors with immunohistochemical markers of cancer stem cells (CSC) CD44+/CD24- in patients with breast cancer (BC) of different molecular subtype and to evaluate their prognostic value. Surgical material of 132 patients with BC stage I-II, age from 23 to 75 years, mean age - 50.2 ± 3.1 years was studied. Clinical, immunohistochemical (expression CD44+/CD24-), morphological, statistical. BC is characterized by heterogeneity of molecular subtypes and expression of markers (CD44+/CD24-). Immunohistochemical study of expression of CSC markers in surgical material has detected their expression in 34 (25.4%) patients with BC of different molecular subtypes. The highest frequency of cells with expression of CSC marker was observed in patients with basal molecular subtype (44.8% patients). Most of BC patients with phenotype CD44+/CD24 had stage I of tumor process (34.3%). Statistical processing of data has showen that Yule colligation coefficient equaled 0.28 (р > 0.05) that argues poor correlation between stage of tumor process and number of tumors with positive expression of CSC markers. Statistical processing of data has showen high correlation between presence of cells with expression of CSC markers and metastases of BC in regional lymph nodes (Yule colligation coefficient equals 0.943; р molecular subtype depending on expression of CSC CD44+/CD24- markers was detected. Survival of patients with basal BC was reliably higher at lack in tumors of cells with CSC markers CD44+/CD24- and, correspondingly, lower at presence of such cells (р markers was not determined (р > 0.05). Significance of tumor cells with markers CD44+/CD24- within the limits of molecular subtype of BC may be additional criterion for advanced biological characteristic of BC, and in patients with BC of basal molecular subtype - for predictive evaluation of individual potential of tumor to aggressive clinical course.

Rb suppresses collective invasion, circulation and metastasis of breast cancer cells in CD44-dependent manner.

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Kui-Jin Kim

Full Text Available Basal-like breast carcinomas (BLCs present with extratumoral lymphovascular invasion, are highly metastatic, presumably through a hematogenous route, have augmented expression of CD44 oncoprotein and relatively low levels of retinoblastoma (Rb tumor suppressor. However, the causal relation among these features is not clear. Here, we show that Rb acts as a key suppressor of multiple stages of metastatic progression. Firstly, Rb suppresses collective cell migration (CCM and CD44-dependent formation of F-actin positive protrusions in vitro and cell-cluster based lymphovascular invasion in vivo. Secondly, Rb inhibits the release of single cancer cells and cell clusters into the hematogenous circulation and subsequent metastatic growth in lungs. Finally, CD44 expression is required for collective motility and all subsequent stages of metastatic progression initiated by loss of Rb function. Altogether, our results suggest that Rb/CD44 pathway is a crucial regulator of CCM and metastatic progression of BLCs and a promising target for anti-BLCs therapy.

CD44-deficiency attenuates the immunologic responses to LPS and delays the onset of endotoxic shock-induced renal inflammation and dysfunction.

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Elena Rampanelli

Full Text Available Acute kidney injury (AKI is a common complication during systemic inflammatory response syndrome (SIRS, a potentially deadly clinical condition characterized by whole-body inflammatory state and organ dysfunction. CD44 is a ubiquitously expressed cell-surface transmembrane receptor with multiple functions in inflammatory processes, including sterile renal inflammation. The present study aimed to assess the role of CD44 in endotoxic shock-induced kidney inflammation and dysfunction by using CD44 KO and WT mice exposed intraperitoneally to LPS for 2, 4, and 24 hours . Upon LPS administration, CD44 expression in WT kidneys was augmented at all time-points. At 2 and 4 hours, CD44 KO animals showed a preserved renal function in comparison to WT mice. In absence of CD44, the pro-inflammatory cytokine levels in plasma and kidneys were lower, while renal expression of the anti-inflammatory cytokine IL-10 was higher. The cytokine levels were associated with decreased leukocyte influx and endothelial activation in CD44 KO kidneys. Furthermore, in vitro assays demonstrated a role of CD44 in enhancing macrophage cytokine responses to LPS and leukocyte migration. In conclusion, our study demonstrates that lack of CD44 impairs the early pro-inflammatory cytokine response to LPS, diminishes leukocyte migration/chemotaxis and endothelial activation, hence, delays endotoxic shock-induced AKI.

Curcumin induced nanoscale CD44 molecular redistribution and antigen-antibody interaction on HepG2 cell surface

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Wang Mu [Department of Chemistry, Jinan University, 601 Huangpu Road West, Tianhe District, Guangzhou 510632 (China); Ruan Yuxia [Department of Ophthalmology, The First Affiliated Hospital, Jinan University, 601 Huangpu Road West, Tianhe District, Guangzhou 510632 (China); Xing Xiaobo; Chen Qian; Peng, Yuan [Department of Chemistry, Jinan University, 601 Huangpu Road West, Tianhe District, Guangzhou 510632 (China); Cai Jiye, E-mail: tjycai@jnu.edu.cn [Department of Chemistry, Jinan University, 601 Huangpu Road West, Tianhe District, Guangzhou 510632 (China)

2011-07-04

Graphical abstract: Highlights: > In this study, we investigate the changes of CD44 expression and distribution on HepG2 cells after curcumin treatment. > We find curcumin is able to change the morphology and ultrastructure of HepG2 cells. > Curcumin can reduce the expression of CD44 molecules and induce the nanoscale molecular redistribution on cell surface. > The binding force between CD44-modified AFM tip and the HepG2 cell surface decreases after curcumin-treatment. - Abstract: The cell surface glycoprotein CD44 was implicated in the progression, metastasis and apoptosis of certain human tumors. In this study, we used atomic force microscope (AFM) to monitor the effect of curcumin on human hepatocellular carcinoma (HepG2) cell surface nanoscale structure. High-resolution imaging revealed that cell morphology and ultrastructure changed a lot after being treated with curcumin. The membrane average roughness increased (10.88 {+-} 4.62 nm to 129.70 {+-} 43.72 nm) and the expression of CD44 decreased (99.79 {+-} 0.16% to 75.14 {+-} 8.37%). Laser scanning confocal microscope (LSCM) imaging showed that CD44 molecules were located on the cell membrane. The florescence intensity in control group was weaker than that in curcumin treated cells. Most of the binding forces between CD44 antibodies and untreated HepG2 cell membrane were around 120-220 pN. After being incubated with curcumin, the major forces focused on 70-150 pN (10 {mu}M curcumin-treated) and 50-120 pN (20 {mu}M curcumin-treated). These results suggested that, as result of nanoscale molecular redistribution, changes of the cell surface were in response to external treatment of curcumin. The combination of AFM and LSCM could be a powerful method to detect the distribution of cell surface molecules and interactions between molecules and their ligands.

Curcumin induced nanoscale CD44 molecular redistribution and antigen-antibody interaction on HepG2 cell surface

International Nuclear Information System (INIS)

Wang Mu; Ruan Yuxia; Xing Xiaobo; Chen Qian; Peng, Yuan; Cai Jiye

2011-01-01

Graphical abstract: Highlights: → In this study, we investigate the changes of CD44 expression and distribution on HepG2 cells after curcumin treatment. → We find curcumin is able to change the morphology and ultrastructure of HepG2 cells. → Curcumin can reduce the expression of CD44 molecules and induce the nanoscale molecular redistribution on cell surface. → The binding force between CD44-modified AFM tip and the HepG2 cell surface decreases after curcumin-treatment. - Abstract: The cell surface glycoprotein CD44 was implicated in the progression, metastasis and apoptosis of certain human tumors. In this study, we used atomic force microscope (AFM) to monitor the effect of curcumin on human hepatocellular carcinoma (HepG2) cell surface nanoscale structure. High-resolution imaging revealed that cell morphology and ultrastructure changed a lot after being treated with curcumin. The membrane average roughness increased (10.88 ± 4.62 nm to 129.70 ± 43.72 nm) and the expression of CD44 decreased (99.79 ± 0.16% to 75.14 ± 8.37%). Laser scanning confocal microscope (LSCM) imaging showed that CD44 molecules were located on the cell membrane. The florescence intensity in control group was weaker than that in curcumin treated cells. Most of the binding forces between CD44 antibodies and untreated HepG2 cell membrane were around 120-220 pN. After being incubated with curcumin, the major forces focused on 70-150 pN (10 μM curcumin-treated) and 50-120 pN (20 μM curcumin-treated). These results suggested that, as result of nanoscale molecular redistribution, changes of the cell surface were in response to external treatment of curcumin. The combination of AFM and LSCM could be a powerful method to detect the distribution of cell surface molecules and interactions between molecules and their ligands.

Enrichment of CD44 in basal-type breast cancer correlates with EMT, cancer stem cell gene profile, and prognosis

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Xu HX

2016-01-01

Full Text Available Hanxiao Xu,1 Yijun Tian,1 Xun Yuan,1 Yu Liu,2 Hua Wu,1 Qian Liu,1 Gen Sheng Wu,3,4 Kongming Wu1 1Department of Oncology, 2Department of Geriatrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People’s Republic of China; 3Department of Oncology, 4Department of Pathology, Karmanos Cancer Institute, Wayne State University School of Medicine, Detroit, MI, USA Abstract: Cluster of differentiation 44 (CD44 is a transmembrane glycoprotein that serves as the receptor for the extracellular matrix component hyaluronic acid. CD44 has been reported to play key roles in cell proliferation, motility, and survival, but its role in breast cancer remains controversial. In this study, we conducted a meta-analysis. A total of 23 published Gene Expression Omnibus databases were included to evaluate the association between CD44 mRNA expression and clinicopathological characteristics or prognosis of the patients with breast cancer. Our analysis revealed that CD44 expression was associated with clinicopathological features, including the histological grade, estrogen receptor status, progesterone receptor status, and human epidermal growth factor receptor-2 status. Higher levels of CD44 expression were observed in the basal subtype of breast cancer both at the mRNA and protein levels (odds ratio [OR] =2.08, 95% confidence interval [CI]: 1.72–2.52; OR =2.11, 95% CI: 1.67–2.68. Patients with CD44 overexpression exhibited significantly worse overall survival (hazard ratio =1.27; 95% CI: 1.04–1.55. Whole gene profile analysis revealed that CD44 expression was enriched in basal-type breast cancer and correlated with epithelial–mesenchymal transition and cancer stem cell gene profiles. In summary, our analyses indicated that CD44 potentially might be a prognostic marker for breast cancer and thus can serve as a therapeutic target for basal-type breast cancer. Keywords: breast cancer, CD44, survival prediction, meta

Soluble CD44 concentration in the serum and peritoneal fluid samples of patients with different stages of endometriosis.

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Mashayekhi, Farhad; Aryaee, Hadis; Mirzajani, Ebrahim; Yasin, Ashraf Ale; Fathi, Abdolsatar

2015-09-01

Endometriosis is a gynecological disease defined by the histological presence of endometrial glands and stroma outside the uterine cavity, most commonly implanted over visceral and peritoneal surface within the female pelvis. CD44 is a membrane protein expressed by human endometrial cells, and it has been shown to promote the adhesion of endometrial cells. The aim of this study was to determine the levels of soluble CD44 (sCD44) in the serum and peritoneal fluid (PF) samples of patients with different stages of endometriosis. 39 PF and serum samples from normal healthy and 130 samples from different stages of patients with endometriosis (33 cases of stage I, 38 stage II, 30 stage III and 29 stage IV) were included in this study. Total protein concentration (TPC) and the level of s-cMet in the serum were determined by Bio-Rad protein assay based on the Bradford dye procedure and enzyme-linked immunosorbent assay, respectively. No significant change in the TPC was seen in the serum of patients with endometriosis when compared to normal controls. Results obtained demonstrated that all serum and peritoneal fluid samples, presented sCD44 expression, whereas, starting from stages I to IV endometriosis, a significant increase of sCD44 expression was observed as compared to control group. The results of this study show that a high expression of sCD44 is correlated with advanced stages of endometriosis. It is also concluded that the detection of serum and/or peritoneal fluid sCD44 may be useful in classifying endometriosis.

Aggravation of Allergic Airway Inflammation by Cigarette Smoke in Mice Is CD44-Dependent.

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Smitha Kumar

Full Text Available Although epidemiological studies reveal that cigarette smoke (CS facilitates the development and exacerbation of allergic asthma, these studies offer limited information on the mechanisms involved. The transmembrane glycoprotein CD44 is involved in cell adhesion and acts as a receptor for hyaluronic acid and osteopontin. We aimed to investigate the role of CD44 in a murine model of CS-facilitated allergic airway inflammation.Wild type (WT and CD44 knock-out (KO mice were exposed simultaneously to house dust mite (HDM extract and CS. Inflammatory cells, hyaluronic acid (HA and osteopontin (OPN levels were measured in bronchoalveolar lavage fluid (BALF. Proinflammatory mediators, goblet cell metaplasia and peribronchial eosinophilia were assessed in lung tissue. T-helper (Th 1, Th2 and Th17 cytokine production was evaluated in mediastinal lymph node cultures.In WT mice, combined HDM/CS exposure increased the number of inflammatory cells and the levels of HA and OPN in BALF and Th2 cytokine production in mediastinal lymph nodes compared to control groups exposed to phosphate buffered saline (PBS/CS, HDM/Air or PBS/Air. Furthermore, HDM/CS exposure significantly increased goblet cell metaplasia, peribronchial eosinophilia and inflammatory mediators in the lung. CD44 KO mice exposed to HDM/CS had significantly fewer inflammatory cells in BALF, an attenuated Th2 cytokine production, as well as decreased goblet cells and peribronchial eosinophils compared to WT mice. In contrast, the levels of inflammatory mediators were similar or higher than in WT mice.We demonstrate for the first time that the aggravation of pulmonary inflammation upon combined exposure to allergen and an environmental pollutant is CD44-dependent. Data from this murine model of concomitant exposure to CS and HDM might be of importance for smoking allergic asthmatics.

Expression of Monocarboxylate Transporters 1, 2, and 4 in Human Tumours and Their Association with CD147 and CD44

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Céline Pinheiro

2010-01-01

Full Text Available Monocarboxylate transporters (MCTs are important cellular pH regulators in cancer cells; however, the value of MCT expression in cancer is still poorly understood. In the present study, we analysed MCT1, MCT2, and MCT4 protein expression in breast, colon, lung, and ovary neoplasms, as well as CD147 and CD44. MCT expression frequency was high and heterogeneous among the different tumours. Comparing with normal tissues, there was an increase in MCT1 and MCT4 expressions in breast carcinoma and a decrease in MCT4 plasma membrane expression in lung cancer. There were associations between CD147 and MCT1 expressions in ovarian cancer as well as between CD147 and MCT4 in both breast and lung cancers. CD44 was only associated with MCT1 plasma membrane expression in lung cancer. An important number of MCT1 positive cases are negative for both chaperones, suggesting that MCT plasma membrane expression in tumours may depend on a yet nonidentified regulatory protein.

Effect of Three Calmodulin Antagonists on Subpopulations of CD44 ...

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Tropical Journal of Pharmaceutical Research is indexed by Science Citation Index (SciSearch), Scopus,. International Pharmaceutical ... cancer stem cells. It is not known, however, whether targeting CD44 can alter the fate of cancer stem cells themselves. In this study, the effect of the calmodulin antagonists (N-(10-.

CDKL5 variants

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Kalscheuer, Vera M.; Hennig, Friederike; Leonard, Helen; Downs, Jenny; Clarke, Angus; Benke, Tim A.; Armstrong, Judith; Pineda, Mercedes; Bailey, Mark E.S.; Cobb, Stuart R.

2017-01-01

Objective: To provide new insights into the interpretation of genetic variants in a rare neurologic disorder, CDKL5 deficiency, in the contexts of population sequencing data and an updated characterization of the CDKL5 gene. Methods: We analyzed all known potentially pathogenic CDKL5 variants by combining data from large-scale population sequencing studies with CDKL5 variants from new and all available clinical cohorts and combined this with computational methods to predict pathogenicity. Results: The study has identified several variants that can be reclassified as benign or likely benign. With the addition of novel CDKL5 variants, we confirm that pathogenic missense variants cluster in the catalytic domain of CDKL5 and reclassify a purported missense variant as having a splicing consequence. We provide further evidence that missense variants in the final 3 exons are likely to be benign and not important to disease pathology. We also describe benign splicing and nonsense variants within these exons, suggesting that isoform hCDKL5_5 is likely to have little or no neurologic significance. We also use the available data to make a preliminary estimate of minimum incidence of CDKL5 deficiency. Conclusions: These findings have implications for genetic diagnosis, providing evidence for the reclassification of specific variants previously thought to result in CDKL5 deficiency. Together, these analyses support the view that the predominant brain isoform in humans (hCDKL5_1) is crucial for normal neurodevelopment and that the catalytic domain is the primary functional domain. PMID:29264392

Expression of Bmi-1, P16, and CD44v6 in Uterine Cervical Carcinoma and Its Clinical Significance

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Weng, Mei-ying; Li, Lin; Feng, Shu-ying; Hong, Shun-jia

2012-01-01

Bmi-1, a putative proto-oncogene, is a core member of the polycomb gene family, which is expressed in many human tumors. The p16 protein negatively regulated cell proliferation, whereas CD44v6 is associated with proliferation as an important protein. Additionally, CD44v6 is an important nuclear antigen closely correlated to tumor metastasis. The present study aims to investigate the expression and significance of Bmi-1, p16, and CD44v6 in uterine cervical carcinoma (UCC). A total of 62 UCC, 30 cervical neoplasic, and 20 normal cervical mucosal tissues were used in the current study. The expression of Bmi-1, p16, and CD44v6 in these tissues was determined using immunohistochemical assay. The relationships among the expression of these indices, the clinicopathologic features of UCC, and the survival rate of UCC patients were also discussed. The correlation between Bmi-1 protein expression and p16 or CD44v6 protein in UCC was analyzed. The expression of Bmi-1, p16, and CD44v6 was significantly high in cervical carcinoma compared with that in the cervical neoplasia and normal colorectal mucosa (P<0.05). The over-expression of Bmi-1 protein in UCC was apparently related to the distant metastasis (P<0.01) and the tumor, nodes and metastasis-classification, i.e. the TNM staging, World Health Organization (P<0.05). Nevertheless, the positive expression of p16 protein in UCC was not significantly associated with the clinicopathologic features (P>0.05). The Kaplan–Meier survival analysis showed that the over-expression of Bmi-1 significantly decreased the survival rate of UCC patients (P<0.05). A strong correlation indicated that there was statistical significance between the expression of Bmi-1 and CD44V6 proteins in UCC (r=0.419, P=0.001). The over-expression of Bmi-1 and CD44v6 protein closely correlate to the tumorigenesis, metastasis, and prognosis of UCC. Bmi-1 and CD44v6 may be used to predict the prognosis of cervical carcinoma. Bmi-1 may indirectly regulate the

Immunohistochemistry Analysis of CD44, EGFR, and p16 in Oral Cavity and Oropharyngeal Squamous Cell Carcinoma.

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Cohen, Erin R; Reis, Isildinha M; Gomez, Carmen; Pereira, Lutecia; Freiser, Monika E; Hoosien, Gia; Franzmann, Elizabeth J

2017-08-01

Objectives We analyze the relationship between CD44, epidermal growth factor receptor (EGFR), and p16 expression in oral cavity and oropharyngeal cancers in a diverse population. We also describe whether particular patterns of staining are associated with progression-free survival and overall survival. Study Design Prospective study, single-blind to pathologist and laboratory technologist. Setting Hospital based. Subjects and Methods Immunohistochemistry, comprising gross staining and cellular expression, was performed and interpreted in a blinded fashion on 24 lip/oral cavity and 40 oropharyngeal cancer specimens collected between 2007 and 2012 from participants of a larger study. Information on overall survival and progression-free survival was obtained from medical records. Results Nineteen cases were clinically p16 positive, 16 of which were oropharyngeal. Oral cavity lesions were more likely to exhibit strong CD44 membrane staining ( P = .0002). Strong CD44 membrane and strong EGFR membrane and/or cytoplasmic staining were more common in p16-negative cancers ( P = .006). Peripheral/mixed gross p16 staining pattern was associated with worse survival than the universal staining on univariate and multivariate analyses ( P = .006, P = .030). This held true when combining gross and cellular localization for p16. For CD44, universal gross staining demonstrated poorer overall survival compared with the peripheral/mixed group ( P = .039). CD44 peripheral/mixed group alone and when combined with universal p16 demonstrated the best survival on multivariate analysis ( P = .010). Conclusion In a diverse population, systematic analysis applying p16, CD44, and EGFR gross staining and cellular localization on immunohistochemistry demonstrates distinct patterns that may have prognostic potential exceeding current methods. Larger studies are warranted to investigate these findings further.

WT1 isoform expression pattern in acute myeloid leukemia.

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Luna, Irene; Such, Esperanza; Cervera, Jose; Barragán, Eva; Ibañez, Mariam; Gómez-Seguí, Inés; López-Pavía, María; Llop, Marta; Fuster, Oscar; Dolz, Sandra; Oltra, Silvestre; Alonso, Carmen; Vera, Belén; Lorenzo, Ignacio; Martínez-Cuadrón, David; Montesinos, Pau; Senent, M Leonor; Moscardó, Federico; Bolufer, Pascual; Sanz, Miguel A

2013-12-01

WT1 plays a dual role in leukemia development, probably due to an imbalance in the expression of the 4 main WT1 isoforms. We quantify their expression and evaluate them in a series of AML patients. Our data showed a predominant expression of isoform D in AML, although in a lower quantity than in normal CD34+ cells. We found a positive correlation between the total WT1 expression and A, B and C isoforms. The overexpression of WT1 in AML might be due to a relative increase in A, B and C isoforms, together with a relative decrease in isoform D expression. Copyright © 2013 Elsevier Ltd. All rights reserved.

Learning-dependent gene expression of CREB1 isoforms in the molluscan brain

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Hisayo Sadamoto

2010-05-01

Full Text Available Cyclic AMP-responsive element binding protein1 (CREB1 has multiple functions in gene regulation. Various studies have reported that CREB1-dependent gene induction is necessary for memory formation and long-lasting behavioral changes in both vertebrates and invertebrates. In the present study, we characterized Lymnaea CREB1 (LymCREB1 mRNA isoforms of spliced variants in the central nervous system (CNS of the pond snail Lymnaea stagnalis. Among these spliced variants, the three isoforms that code a whole LymCREB1 protein are considered to be the activators for gene regulation. The other four isoforms, which code truncated LymCREB1 proteins with no kinase inducible domain, are the repressors. For a better understanding of the possible roles of different LymCREB1 isoforms, the expression level of these isoform mRNAs was investigated by a real-time quantitative RT-PCR method. Further, we examined the changes in gene expression for all the isoforms in the CNS after conditioned taste aversion (CTA learning or backward conditioning as a control. The results showed that CTA learning increased LymCREB1 gene expression, but it did not change the activator/repressor ratio. Our findings showed that the repressor isoforms, as well as the activator ones, are expressed in large amounts in the CNS, and the gene expression of CREB1 isoforms appeared to be specific for the given stimulus. This was the first quantitative analysis of the expression patterns of CREB1 isoforms at the mRNA level and their association with learning behavior.

Expression of COX-2, CD44v6 and CD147 and relationship with invasion and lymph node metastasis in hypopharyngeal squamous cell carcinoma.

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Qing Yang

Full Text Available To assess the expression of COX-2,CD44v6 and CD147 in hypopharyngeal squamous cell carcinomas and the three biomarkers correlation with tumor invasion and lymph node metastasis of Chinese people. 101 cases of surgically excised primary tumor were included in this study, and 40 tissues of epithelium adjacent to carcinoma were used as controls. We characterized the immunohistochemical expression of COX-2, CD44v6, and CD147 in 141 formalin-fixed, paraffin-embedded tissues, and measured the mean optical density (OD of the positive area to identify the expression of the three bio-markers and relationship with tumor invasion and lymph node metastasis. Our study demonstrates that the expression of the COX-2 and CD147 were significantly increased in carcinoma tissues compared to the epithelium adjacent to carcinoma. We also observed that the expression of COX-2, CD44v6, and CD147 were significantly associated with T classification, lymph node metastasis and clinical stage. There was strong significant correlation among the three biomarkers as well. Additionally, we indicated that recurrence and ≥ P50 level of COX-2 expression had an independent prognostic effect on prognosis. In conclusion, the three biomarkers play important roles in tumor invasion and lymph node metastases and might be valuable indicators of tumor metastasis in hypopharyngeal squamous cell carcinoma.

Challenging the roles of CD44 and lipolysis stimulated lipoprotein receptor in conveying Clostridium perfringens iota toxin cytotoxicity in breast cancer.

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Fagan-Solis, Katerina D; Reaves, Denise K; Rangel, M Cristina; Popoff, Michel R; Stiles, Bradley G; Fleming, Jodie M

2014-07-02

Translational exploration of bacterial toxins has come to the forefront of research given their potential as a chemotherapeutic tool. Studies in select tissues have demonstrated that Clostridium perfringens iota toxin binds to CD44 and lipolysis stimulated lipoprotein receptor (LSR) cell-surface proteins. We recently demonstrated that LSR expression correlates with estrogen receptor positive breast cancers and that LSR signaling directs aggressive, tumor-initiating cell behaviors. Herein, we identify the mechanisms of iota toxin cytotoxicity in a tissue-specific, breast cancer model with the ultimate goal of laying the foundation for using iota toxin as a targeted breast cancer therapy. In vitro model systems were used to determine the cytotoxic effect of iota toxin on breast cancer intrinsic subtypes. The use of overexpression and knockdown technologies confirmed the roles of LSR and CD44 in regulating iota toxin endocytosis and induction of cell death. Lastly, cytotoxicity assays were used to demonstrate the effect of iota toxin on a validated set of tamoxifen resistant breast cancer cell lines. Treatment of 14 breast cancer cell lines revealed that LSR+/CD44- lines were highly sensitive, LSR+/CD44+ lines were slightly sensitive, and LSR-/CD44+ lines were resistant to iota cytotoxicity. Reduction in LSR expression resulted in a significant decrease in toxin sensitivity; however, overexpression of CD44 conveyed toxin resistance. CD44 overexpression was correlated with decreased toxin-stimulated lysosome formation and decreased cytosolic levels of iota toxin. These findings indicated that expression of CD44 drives iota toxin resistance through inhibition of endocytosis in breast cancer cells, a role not previously defined for CD44. Moreover, tamoxifen-resistant breast cancer cells exhibited robust expression of LSR and were highly sensitive to iota-induced cytotoxicity. Collectively, these data are the first to show that iota toxin has the potential to be an

The CD44(high tumorigenic subsets in lung cancer biospecimens are enriched for low miR-34a expression.

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Saroj K Basak

Full Text Available Cellular heterogeneity is an integral part of cancer development and progression. Progression can be associated with emergence of cells that exhibit high phenotypic plasticity (including "de-differentiation" to primitive developmental states, and aggressive behavioral properties (including high tumorigenic potentials. We observed that many biomarkers that are used to identify Cancer Stem Cells (CSC can label cell subsets in an advanced clinical stage of lung cancer (malignant pleural effusions, or MPE. Thus, CSC-biomarkers may be useful for live sorting functionally distinct cell subsets from individual tumors, which may enable investigators to hone in on the molecular basis for functional heterogeneity. We demonstrate that the CD44(hi (CD44-high cancer cell subsets display higher clonal, colony forming potential than CD44(lo cells (n=3 and are also tumorigenic (n=2/2 when transplanted in mouse xenograft model. The CD44(hi subsets express different levels of embryonal (de-differentiation markers or chromatin regulators. In archived lung cancer tissues, ALDH markers co-localize more with CD44 in squamous cell carcinoma (n=5/7 than Adeno Carcinoma (n=1/12. MPE cancer cells and a lung cancer cell line (NCI-H-2122 exhibit chromosomal abnormalities and 1p36 deletion (n=3/3. Since miR-34a maps to the 1p36 deletion site, low miR-34a expression levels were detected in these cells. The colony forming efficiency of CD44(hi cells, characteristic property of CSC, can be inhibited by mir-34a replacement in these samples. In addition the highly tumorigenic CD44(hi cells are enriched for cells in the G2 phase of cell cycle.

Immunohistochemical expression of CD44s in human neuroblastic tumors: Moroccan experience and highlights on current data

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2013-01-01

Background Peripheral neuroblastic tumors (pNTs), including neuroblastoma (NB), ganglioneuroblastoma (GNB) and ganglioneuroma (GN), are extremely heterogeneous pediatric tumors responsible for 15 % of childhood cancer death. The aim of the study was to evaluate the expression of CD44s (‘s’: standard form) cell adhesion molecule by comparison with other specific prognostic markers. Methods An immunohistochemical profile of 32 formalin-fixed paraffin-embedded pNTs tissues, diagnosed between January 2007 and December 2010, was carried out. Results Our results have demonstrated the association of CD44s negative pNTs cells to lack of differentiation and tumour progression. A significant association between absence of CD44s expression and metastasis in human pNTs has been reported. We also found that expression of CD44s defines subgroups of patients without MYCN amplification as evidenced by its association with low INSS stages, absence of metastasis and favorable Shimada histology. Discussion These findings support the thesis of the role of CD44s glycoprotein in the invasive growth potential of neoplastic cells and suggest that its expression could be taken into consideration in the therapeutic approaches targeting metastases. Virtual Slides The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1034403150888863 Résumé Introduction les tumeurs neuroblastiques périphériques (TNPs), comprenant le neuroblastome (NB), le ganglioneuroblastome (GNB) et le ganglioneurome (GN), sont des tumeurs pédiatriques extrêmement hétérogènes responsables de 15% des décès par cancer chez les enfants. Le but de cette étude était d’évaluer l’expression de la molécule d’adhésion cellulaire CD44s (‘s’: pour standard) par rapport à d’autres facteurs pronostiques spécifiques. Méthodes Un profil immunohistochimique de 32 TNPs fixées au formol et incluses en paraffine, diagnostiquées entre Janvier 2007 et D�

APPRIS 2017: principal isoforms for multiple gene sets

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Rodriguez-Rivas, Juan; Di Domenico, Tomás; Vázquez, Jesús; Valencia, Alfonso

2018-01-01

Abstract The APPRIS database (http://appris-tools.org) uses protein structural and functional features and information from cross-species conservation to annotate splice isoforms in protein-coding genes. APPRIS selects a single protein isoform, the ‘principal’ isoform, as the reference for each gene based on these annotations. A single main splice isoform reflects the biological reality for most protein coding genes and APPRIS principal isoforms are the best predictors of these main proteins isoforms. Here, we present the updates to the database, new developments that include the addition of three new species (chimpanzee, Drosophila melangaster and Caenorhabditis elegans), the expansion of APPRIS to cover the RefSeq gene set and the UniProtKB proteome for six species and refinements in the core methods that make up the annotation pipeline. In addition APPRIS now provides a measure of reliability for individual principal isoforms and updates with each release of the GENCODE/Ensembl and RefSeq reference sets. The individual GENCODE/Ensembl, RefSeq and UniProtKB reference gene sets for six organisms have been merged to produce common sets of splice variants. PMID:29069475

Overexpression of CD44 accompanies acquired tamoxifen resistance in MCF7 cells and augments their sensitivity to the stromal factors, heregulin and hyaluronan

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Hiscox Stephen

2012-10-01

Full Text Available Abstract Background Acquired resistance to endocrine therapy in breast cancer is a significant problem with relapse being associated with local and/or regional recurrence and frequent distant metastases. Breast cancer cell models reveal that endocrine resistance is accompanied by a gain in aggressive behaviour driven in part through altered growth factor receptor signalling, particularly involving erbB family receptors. Recently we identified that CD44, a transmembrane cell adhesion receptor known to interact with growth factor receptors, is upregulated in tamoxifen-resistant (TamR MCF7 breast cancer cells. The purpose of this study was to explore the consequences of CD44 upregulation in an MCF7 cell model of acquired tamoxifen resistance, specifically with respect to the hypothesis that CD44 may influence erbB activity to promote an adverse phenotype. Methods CD44 expression in MCF7 and TamR cells was assessed by RT-PCR, Western blotting and immunocytochemistry. Immunofluorescence and immunoprecipitation studies revealed CD44-erbB associations. TamR cells (± siRNA-mediated CD44 suppression or MCF7 cells (± transfection with the CD44 gene were treated with the CD44 ligand, hyaluronon (HA, or heregulin and their in vitro growth (MTT, migration (Boyden chamber and wound healing and invasion (Matrigel transwell migration determined. erbB signalling was assessed using Western blotting. The effect of HA on erbB family dimerisation in TamR cells was determined by immunoprecipitation in the presence or absence of CD44 siRNA. Results TamR cells overexpressed CD44 where it was seen to associate with erbB2 at the cell surface. siRNA-mediated suppression of CD44 in TamR cells significantly attenuated their response to heregulin, inhibiting heregulin-induced cell migration and invasion. Furthermore, TamR cells exhibited enhanced sensitivity to HA, with HA treatment resulting in modulation of erbB dimerisation, ligand-independent activation of erbB2

Overexpression of CD44 accompanies acquired tamoxifen resistance in MCF7 cells and augments their sensitivity to the stromal factors, heregulin and hyaluronan

International Nuclear Information System (INIS)

Hiscox, Stephen; Gee, Julia; Baruha, Bedanta; Smith, Chris; Bellerby, Rebecca; Goddard, Lindy; Jordan, Nicola; Poghosyan, Zaruhi; Nicholson, Robert I; Barrett-Lee, Peter

2012-01-01

Acquired resistance to endocrine therapy in breast cancer is a significant problem with relapse being associated with local and/or regional recurrence and frequent distant metastases. Breast cancer cell models reveal that endocrine resistance is accompanied by a gain in aggressive behaviour driven in part through altered growth factor receptor signalling, particularly involving erbB family receptors. Recently we identified that CD44, a transmembrane cell adhesion receptor known to interact with growth factor receptors, is upregulated in tamoxifen-resistant (TamR) MCF7 breast cancer cells. The purpose of this study was to explore the consequences of CD44 upregulation in an MCF7 cell model of acquired tamoxifen resistance, specifically with respect to the hypothesis that CD44 may influence erbB activity to promote an adverse phenotype. CD44 expression in MCF7 and TamR cells was assessed by RT-PCR, Western blotting and immunocytochemistry. Immunofluorescence and immunoprecipitation studies revealed CD44-erbB associations. TamR cells (± siRNA-mediated CD44 suppression) or MCF7 cells (± transfection with the CD44 gene) were treated with the CD44 ligand, hyaluronon (HA), or heregulin and their in vitro growth (MTT), migration (Boyden chamber and wound healing) and invasion (Matrigel transwell migration) determined. erbB signalling was assessed using Western blotting. The effect of HA on erbB family dimerisation in TamR cells was determined by immunoprecipitation in the presence or absence of CD44 siRNA. TamR cells overexpressed CD44 where it was seen to associate with erbB2 at the cell surface. siRNA-mediated suppression of CD44 in TamR cells significantly attenuated their response to heregulin, inhibiting heregulin-induced cell migration and invasion. Furthermore, TamR cells exhibited enhanced sensitivity to HA, with HA treatment resulting in modulation of erbB dimerisation, ligand-independent activation of erbB2 and EGFR and induction of cell migration

CD44+/CD24- breast cancer cells exhibit phenotypic reversion in three-dimensional self-assembling peptide RADA16 nanofiber scaffold

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Mi K

2015-04-01

Full Text Available Kun Mi,1 Zhihua Xing2 1Department of Biochemistry and Molecular Biology, Sichuan Cancer Hospital and Institute, 2Laboratory of Ethnopharmacology, Institute for Nanobiomedical Technology and Membrane Biology, West China Hospital, Sichuan University, Chengdu, People’s Republic of China Background: Self-assembling peptide nanofiber scaffolds have been shown to be a ­permissive biological material for tissue repair, cell proliferation, differentiation, etc. Recently, a subpopulation (CD44+/CD24- of breast cancer cells has been reported to have stem/progenitor cell properties. The aim of this study was to investigate whether this subpopulation of cancer cells have different phenotypes in self-assembling COCH3-RADARADARADARADA-CONH2 (RADA16 peptide nanofiber scaffold compared with Matrigel® (BD Biosciences, Two Oak Park, Bedford, MA, USA and collagen I.Methods: CD44 and CD24 expression was determined by flow cytometry. Cell proliferation was measured by 5-bromo-2'-deoxyuridine assay and DNA content measurement. Immunostaining was used to indicate the morphologies of cells in three-dimensional (3D cultures of different scaffolds and the localization of β-catenin in the colonies. Western blot was used to determine the expression of signaling proteins. In vitro migration assay and inoculation into nude mice were used to evaluate invasion and tumorigenesis in vivo.Results: The breast cancer cell line MDA-MB-435S contained a high percentage (>99% of CD44+/CD24- cells, which exhibited phenotypic reversion in 3D RADA16 nanofiber scaffold compared with collagen I and Matrigel. The newly formed reverted acini-like colonies reassembled a basement membrane and reorganized their cytoskeletons. At the same time, cells cultured and embedded in RADA16 peptide scaffold exhibited growth arrest. Also, they exhibited different migration potential, which links their migration ability with their cellular morphology. Consistent with studies in vitro, the in vivo tumor

A mesenchymal-like phenotype and expression of CD44 predict lack of apoptotic response to sorafenib in liver tumor cells.

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Fernando, Joan; Malfettone, Andrea; Cepeda, Edgar B; Vilarrasa-Blasi, Roser; Bertran, Esther; Raimondi, Giulia; Fabra, Àngels; Alvarez-Barrientos, Alberto; Fernández-Salguero, Pedro; Fernández-Rodríguez, Conrado M; Giannelli, Gianluigi; Sancho, Patricia; Fabregat, Isabel

2015-02-15

The multikinase inhibitor sorafenib is the only effective drug in advanced cases of hepatocellular carcinoma (HCC). However, response differs among patients and effectiveness only implies a delay. We have recently described that sorafenib sensitizes HCC cells to apoptosis. In this work, we have explored the response to this drug of six different liver tumor cell lines to define a phenotypic signature that may predict lack of response in HCC patients. Results have indicated that liver tumor cells that show a mesenchymal-like phenotype, resistance to the suppressor effects of transforming growth factor beta (TGF-β) and high expression of the stem cell marker CD44 were refractory to sorafenib-induced cell death in in vitro studies, which correlated with lack of response to sorafenib in nude mice xenograft models of human HCC. In contrast, epithelial-like cells expressing the stem-related proteins EpCAM or CD133 were sensitive to sorafenib-induced apoptosis both in vitro and in vivo. A cross-talk between the TGF-β pathway and the acquisition of a mesenchymal-like phenotype with up-regulation of CD44 expression was found in the HCC cell lines. Targeted CD44 knock-down in the mesenchymal-like cells indicated that CD44 plays an active role in protecting HCC cells from sorafenib-induced apoptosis. However, CD44 effect requires a TGF-β-induced mesenchymal background, since the only overexpression of CD44 in epithelial-like HCC cells is not sufficient to impair sorafenib-induced cell death. In conclusion, a mesenchymal profile and expression of CD44, linked to activation of the TGF-β pathway, may predict lack of response to sorafenib in HCC patients. © 2014 UICC.

An Analysis of Trafficking Receptors Shows that CD44 and P-Selectin Glycoprotein Ligand-1 Collectively Control the Migration of Activated Human T-Cells

KAUST Repository

Ali, Amal J.; AbuElela, Ayman; Merzaban, Jasmeen

2017-01-01

-selectin ligands, to CD44, a ligand that has not previously been characterized as an E-selectin ligand on activated human T-cells. We showed that CD44 acts as a functional E-selectin ligand when expressed on both CD4+ and CD8+ T-cells. Moreover, the CD44 protein

[Dectection of G3BP and CD44v6 in the tissues of laryngeal squamous cell carcinoma and their clinical significance].

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Luo, Dahu; Lou, Weihua

2017-07-01

Objective To study the expressions of RNA-binding Ras-GAP SH3 binding protein (G3BP) and tumor stem cell marker CD44v6 in laryngeal squamous cell carcinoma and their correlations with angiogenesis. Methods We collected the cancer tissues and corresponding paracancerous tissues from 56 patients with laryngeal squamous cell carcinoma. The expressions of G3BP and CD44v6 proteins were detected by Western blotting in cancer tissues and corresponding paracancerous tissues; the expressions of G3BP, CD44v6 and vascular endothelial growth factor A (VEGF-A) were tested by immunohistochemistry. Thereafter, we compared the positive expression rates of G3BP and CD44v6 between in cancer tissues and in normal tissues, analyzed the correlations between the expressions of G3BP, CD44v6 and the laryngeal squamous cell carcinoma features as well as their correlations with microvessel density (MVD) that was determined by FVIIIAg immunohistochemistry. Results Western blotting showed that the expressions of G3BP and CD44v6 proteins in the laryngeal squamous cell carcinoma were higher than those in the paracancerous tissues. Immunohistochemistry showed that compared with the paracancerous tissues, G3BP, CD44v6 and VEGF-A expressions (the positive rates are 58.9%, 53.6%, 46.4%, respectively) were higher in cancer tissues. The positive rates of G3BP and CD44v6 in cancer tissues were related with the clinical stage, recurrence or metastasis, and lymph node metastasis of laryngeal squamous cell carcinoma, but had nothing to do with patients' age and tumor size. Pearson correlation analysis showed the expressions of both G3BP and CD44v6 were positively correlated with VEGF-A (r=0.741, r=0.756). MVD values were significantly higher in the G3BP and CD44v6 positive cases than in paracancerous tissues, but there was no difference in MVD between those without G3BP and CD44v6 positive expressions and the paracancerous tissues. Conclusion The positive expression rates of G3BP and CD44v6 in laryngeal

Two-dimensional zymography differentiates gelatinase isoforms in stimulated microglial cells and in brain tissues of acute brain injuries.

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Chen, Shanyan; Meng, Fanjun; Chen, Zhenzhou; Tomlinson, Brittany N; Wesley, Jennifer M; Sun, Grace Y; Whaley-Connell, Adam T; Sowers, James R; Cui, Jiankun; Gu, Zezong

2015-01-01

Excessive activation of gelatinases (MMP-2/-9) is a key cause of detrimental outcomes in neurodegenerative diseases. A single-dimension zymography has been widely used to determine gelatinase expression and activity, but this method is inadequate in resolving complex enzyme isoforms, because gelatinase expression and activity could be modified at transcriptional and posttranslational levels. In this study, we investigated gelatinase isoforms under in vitro and in vivo conditions using two-dimensional (2D) gelatin zymography electrophoresis, a protocol allowing separation of proteins based on isoelectric points (pI) and molecular weights. We observed organomercuric chemical 4-aminophenylmercuric acetate-induced activation of MMP-2 isoforms with variant pI values in the conditioned medium of human fibrosarcoma HT1080 cells. Studies with murine BV-2 microglial cells indicated a series of proform MMP-9 spots separated by variant pI values due to stimulation with lipopolysaccharide (LPS). The MMP-9 pI values were shifted after treatment with alkaline phosphatase, suggesting presence of phosphorylated isoforms due to the proinflammatory stimulation. Similar MMP-9 isoforms with variant pI values in the same molecular weight were also found in mouse brains after ischemic and traumatic brain injuries. In contrast, there was no detectable pI differentiation of MMP-9 in the brains of chronic Zucker obese rats. These results demonstrated effective use of 2D zymography to separate modified MMP isoforms with variant pI values and to detect posttranslational modifications under different pathological conditions.

Proliferation marker pKi-67 occurs in different isoforms with various cellular effects.

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Schmidt, Mirko H H; Broll, Rainer; Bruch, Hans-Peter; Finniss, Susan; Bögler, Oliver; Duchrow, Michael

2004-04-15

The Ki-67 antigen, pKi-67, is a commonly used proliferation marker in research and pathology. It has been recognized that the protein exists in two different splice variants that differ in one exon. In the current work, we present three new splice variants of human pKi-67 consisting of two naturally occurring isoforms and one atypical version. Additionally, data is presented indicating that alternative splicing of the pKi-67 N-terminus is common in tumor cell lines. Analyzing 93 tissues mainly consisting of brain tumor specimens, we found evidence that long and short isoform can be expressed independently of each other. Induction of mitosis in human peripheral blood mononuclear cells revealed that short pKi-67 appears earlier in the cell cycle than the long isoform and reaches its expression maximum when transcription of the latter sets in. Finally, transfection of mammalian culture cells with exon 7 (specific for the long pKi-67 isoform and not present in the short isoform) in a tetracycline regulated expression system decreased the rate of cell proliferation without affecting the cell cycle. In summary, we present evidence that the pKi-67 N-terminus is differentially spliced resulting in at least five different isoforms with different functions. Copyright 2004 Wiley-Liss, Inc.

CD44 and SSEA-4 positive cells in an oral cancer cell line HSC-4 possess cancer stem-like cell characteristics.

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Noto, Zenko; Yoshida, Toshiko; Okabe, Motonori; Koike, Chika; Fathy, Moustafa; Tsuno, Hiroaki; Tomihara, Kei; Arai, Naoya; Noguchi, Makoto; Nikaido, Toshio

2013-08-01

Cancer may be derived from cancer stem-like cells (CSCs), which are tumor-initiating cells that have properties similar to those of stem cells. Identification and isolation of CSCs needs to be improved further. CSCs markers were examined in human oral cancer cell lines by flow cytometry. The stem cell properties of subpopulations expressing different markers were assessed further by in vitro sphere formation assays, expression of stemness genes, drug resistance assays, and the ability to form tumors in nude mice. We demonstrated that CSCs could be isolated by the cell surface markers CD44 and stage-specific embryonic antigen-4 (SSEA-4). CD44+SSEA-4+ cells exhibited cancer stem-like properties, including extensive self-renewal into the bulk of cancer cells. In vivo xenograft experiments indicated that CD44+SSEA-4+ cells exhibit the highest tumorigenic capacity compared with the remaining subpopulations and parental cells. Double-positive cells for CD44 and SSEA-4 exhibited preferential expression of some stemness genes and were more resistant to the anticancer drugs, cisplatin and 5-fluorouracil (5-FU). In addition, cells expressing CD44 and SSEA-4 were detected in all tumor specimens analyzed, while coexpression of CD44 and SSEA-4 was not detectable in normal oral mucosa. Our findings suggest that CD44+SSEA-4+ cells exhibit the characteristics of CSCs in oral squamous cell carcinoma and provide a target for the development of more effective therapies. Copyright © 2013 Elsevier Ltd. All rights reserved.

IgE recognition of chimeric isoforms of the honeybee (Apis mellifera) venom allergen Api m 10 evaluated by protein array technology.

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Van Vaerenbergh, Matthias; De Smet, Lina; Rafei-Shamsabadi, David; Blank, Simon; Spillner, Edzard; Ebo, Didier G; Devreese, Bart; Jakob, Thilo; de Graaf, Dirk C

2015-02-01

Api m 10 has recently been established as novel major allergen that is recognized by more than 60% of honeybee venom (HBV) allergic patients. Previous studies suggest Api m 10 protein heterogeneity which may have implications for diagnosis and immunotherapy of HBV allergy. In the present study, RT-PCR revealed the expression of at least nine additional Api m 10 transcript isoforms by the venom glands. Two distinct mechanisms are responsible for the generation of these isoforms: while the previously known variant 2 is produced by an alternative splicing event, novel identified isoforms are intragenic chimeric transcripts. To the best of our knowledge, this is the first report of the identification of chimeric transcripts generated by the honeybee. By a retrospective proteomic analysis we found evidence for the presence of several of these isoforms in the venom proteome. Additionally, we analyzed IgE reactivity to different isoforms by protein array technology using sera from HBV allergic patients, which revealed that IgE recognition of Api m 10 is both isoform- and patient-specific. While it was previously demonstrated that the majority of HBV allergic patients display IgE reactivity to variant 2, our study also shows that some patients lacking IgE antibodies for variant 2 display IgE reactivity to two of the novel identified Api m 10 variants, i.e. variants 3 and 4. Copyright © 2014 Elsevier Ltd. All rights reserved.

CCR2 and CD44 promote inflammatory cell recruitment during fatty liver formation in a lithogenic diet fed mouse model.

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Charlotte E Egan

Full Text Available Non-alcoholic fatty liver disease (NAFLD is a common disease with a spectrum of presentations. The current study utilized a lithogenic diet model of NAFLD. The diet was fed to mice that are either resistant (AKR or susceptible (BALB/c and C57BL/6 to hepatitis followed by molecular and flow cytometric analysis. Following this, a similar approach was taken in congenic mice with specific mutations in immunological genes. The initial study identified a significant and profound increase in multiple ligands for the chemokine receptor CCR2 and an increase in CD44 expression in susceptible C57BL/6 (B6 but not resistant AKR mice. Ccr2(-/- mice were completely protected from hepatitis and Cd44(-/- mice were partially protected. Despite protection from inflammation, both strains displayed similar histological steatosis scores and significant increases in serum liver enzymes. CD45(+CD44(+ cells bound to hyaluronic acid (HA in diet fed B6 mice but not Cd44(-/- or Ccr2(-/- mice. Ccr2(-/- mice displayed a diminished HA binding phenotype most notably in monocytes, and CD8(+ T-cells. In conclusion, this study demonstrates that absence of CCR2 completely and CD44 partially reduces hepatic leukocyte recruitment. These data also provide evidence that there are multiple redundant CCR2 ligands produced during hepatic lipid accumulation and describes the induction of a strong HA binding phenotype in response to LD feeding in some subsets of leukocytes from susceptible strains.

The leukocyte common antigen (CD45) on human pre-B leukemia cells: variant glycoprotein form expression during the cell exposure to phorbol ester is blocked by a nonselective protein kinase inhibitor H7

International Nuclear Information System (INIS)

Duraj, J.; Sedlak, J.; Chorvath, B.; Rauko, P.

1997-01-01

The human pre-B acute lymphoblastic leukemia cell line REH6 was utilized for characterization of CD45 glycoprotein by monoclonal antibodies (mAb) recognizing four distinct CD45 antigen specificities, i.e. nonrestricted CD45, restricted, CD45RA, CD45RB and CD45R0. Immunoprecipitation revealed two antigen specificities on REH6 cells of m.w. 220 kDa and 190 kDa, both presenting wide range of isoelectric point pI∼6.0-7.5. Nonrestricted CD45 epitopes were not affected by the sialyl acid cleavage with sodium meta-periodate or neuraminidase, but were sensitive to both, tunicamycin, the N-glycosylation inhibitor and monensin, an inhibitor of protein transport through the Golgi compartment. O-sialoglycoprotein endopeptidase from Pasteurella haemolytica A1 partially cleaved CD45RA and CD45RB epitopes, while nonrestricted CD45 determinants were not affected by this enzyme. Limited proteolysis of this antigen resulted in the appearance of 160-180 kDa peptide domains which retained CD45 epitopes. Further, the treatment of cells with phorbol myristate acetate (PMA) induced marked down-regulation of 220 and 190 kDa isoforms and the appearance of new 210, 180 and 170 kDa variant glycoprotein forms which were not found on parental cells. This PMA effect was not accompanied by the programmed cell death and was markedly blocked by a nonselective protein kinase (PK) inhibitor iso-quinoline sulfonamide H7. Modulation of CD45 by phorbol esters might serve as an in vitro model for an additional insight into the function of CD45 in hematopoietic cells. (author)

Urothelial CD44 facilitates Escherichia coli infection of the murine urinary tract

NARCIS (Netherlands)

Rouschop, Kasper M. A.; Sylva, Marc; Teske, Gwendoline J. D.; Hoedemaeker, Inge; Pals, Steven T.; Weening, Jan J.; van der Poll, Tom; Florquin, Sandrine

2006-01-01

Escherichia coli is the most common pathogen found in urinary tract infections (UTIs), mainly affecting children and women. We report that CD44, a hyaluronic acid (HA) binding protein that mediates cell-cell and cell-matrix interactions, facilitates the interaction of E. coli with urothelial cells

α6 Integrin and CD44 enrich for a primary keratinocyte population that displays resistance to UV-induced apoptosis.

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Helen Wray

Full Text Available Epidermal human keratinocytes are exposed to a wide range of environmental genotoxic insults, including the UV component of solar radiation. Epidermal homeostasis in response to cellular or tissue damage is maintained by a population of keratinocyte stem cells (KSC that reside in the basal layer of the epithelium. Using cell sorting based on cell-surface markers, we have identified a novel α6 integrin(high+/CD44(+ sub-population of basal keratinocytes. These α6 integrin(high+/CD44(+ keratinocytes have both high proliferative potential, form colonies in culture that have characteristics of holoclones and have a unique pattern of resistance to apoptosis induced by UVB radiation or by agents that induce single- or double strand DNA breaks. Resistance to UVB induced apoptosis in the α6 integrin(high+/CD44(+ cells involved increased expression of TAp63 and was overcome by PI-3 kinase inhibition. In marked contrast, the α6 integrin(high+/CD44(+ cells were sensitive to apoptosis induced by the cross-linking agent cisplatin, and imatinib inhibition of c-Abl blocked the ability of cisplatin to kill α6 integrin(high+/CD44(+ cells. Our findings reveal a population of basal keratinocytes with long-term proliferative properties that display specific patterns of apoptotic resistance that is dependent upon the genotoxic stimulus, and provide insights into how these cells can be targeted with chemotherapeutic agents.

Biomarker screening of oral cancer cell lines revealed sub-populations of CD133-, CD44-, CD24- and ALDH1- positive cancer stem cells

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Kendall K

2013-05-01

Full Text Available Head and neck squamous cell carcinoma (HNSCC ranks sixth worldwide for cancer-related mortality. For the past several decades the mainstay of treatment for HNSCC has been surgery and external beam radiation, although more recent trials combining chemotherapy and radiation have demonstrated improvements. However, cancer recurrence and treatment failures continue to occur in a significant percentage of patients. Recent advances in tumor biology have led to the discovery that many cancers, including HNSCC, may contain subpopulations of cells with stem cell-like properties that may explain relapse and recurrence. The objective of this study was to screen existing oral cancer cell lines for biomarkers specific for cells with stem cell-like properties. RNA was isolated for RT-PCR screening using primers for specific mRNA of the biomarkers: CD44, CD24, CD133, NANOG, Nestin, ALDH1, and ABCG2 in CAL27, SCC25 and SCC15 cells. This analysis revealed that some oral cancer cell lines (CAL27 and SCC25 may contain small subpopulations of adhesion- and contact-independent cells (AiDC that also express tumor stem cell markers, including CD44, CD133, and CD24. In addition, CAL27 cells also expressed the intracellular tumor stem cell markers, ALDH1 and ABCG2. Isolation and culture of the adhesion- and contact-independent cells from CAL27 and SCC25 populations revealed differential proliferation rates and more robust inhibition by the MEK inhibitor PD98059, as well as the chemotherapeutic agents Cisplatin and Paclitaxel, within the AiDC CAL27 cells. At least one oral cancer cell line (CAL27 contained subpopulations of cells that express specific biomarkers associated with tumor stem cells which were morphologically and phenotypically distinct from other cells within this cell line.

The macrophage scavenger receptor CD163

DEFF Research Database (Denmark)

Nielsen, Marianne Jensby; Madsen, Mette; Møller, Holger J

2006-01-01

CD163 is the monocyte/macrophage-specific receptor for haptoglobin-hemoglobin (Hp-Hb) complexes. The cytoplasmic tail of human CD163 exists as a short tail variant and two long tail variants. Reverse transcriptase-polymerase chain reaction analysis indicated that all three CD163 variants are subs......CD163 is the monocyte/macrophage-specific receptor for haptoglobin-hemoglobin (Hp-Hb) complexes. The cytoplasmic tail of human CD163 exists as a short tail variant and two long tail variants. Reverse transcriptase-polymerase chain reaction analysis indicated that all three CD163 variants...

Hyaluronan, CD44, and Emmprin Regulate Lactate Efflux and Membrane Localization of Monocarboxylate Transporters in Human Breast Carcinoma Cells

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Slomiany, Mark G.; Grass, G. Daniel; Robertson, Angela D.; Yang, Xiao Y.; Maria, Bernard L.; Beeson, Craig; Toole, Bryan P.

2013-01-01

Interactions of hyaluronan with CD44 in tumor cells play important cooperative roles in various aspects of malignancy and drug resistance. Emmprin (CD147; basigin)is a cell surface glycoprotein of the immunoglobulin superfamily that is highly up-regulated in malignant cancer cells and stimulates hyaluronan production, as well as several downstream signaling pathways. Emmprin also interacts with various monocarboxylate transporters (MCT). Malignant cancer cells use the glycolytic pathway and require MCTs to efflux lactate that results from glycolysis. Glycolysis and lactate secretion contribute to malignant cell behaviors and drug resistance in tumor cells. In the present study, we find that perturbation of endogenous hyaluronan, using small hyaluronan oligosaccharides, rapidly inhibits lactate efflux from breast carcinoma cells; down-regulation of emmprin, using emmprin small interfering RNA, also results in decreased efflux. In addition, we find that CD44 coimmunoprecipitates with MCT1, MCT4, and emmprin and colocalizes with these proteins at the plasma membrane. Moreover, after treatment of the cells with hyaluronan oligosaccharides, CD44, MCT1, and MCT4 become localized intracellularly whereas emmprin remains at the cell membrane. Together, these data indicate that constitutive interactions among hyaluronan, CD44, and emmprin contribute to regulation of MCT localization and function in the plasma membrane of breast carcinoma cells. PMID:19176383

Novel Dual Mitochondrial and CD44 Receptor Targeting Nanoparticles for Redox Stimuli-Triggered Release

Science.gov (United States)

Wang, Kaili; Qi, Mengjiao; Guo, Chunjing; Yu, Yueming; Wang, Bingjie; Fang, Lei; Liu, Mengna; Wang, Zhen; Fan, Xinxin; Chen, Daquan

2018-02-01

In this work, novel mitochondrial and CD44 receptor dual-targeting redox-sensitive multifunctional nanoparticles (micelles) based on oligomeric hyaluronic acid (oHA) were proposed. The amphiphilic nanocarrier was prepared by (5-carboxypentyl)triphenylphosphonium bromide (TPP), oligomeric hyaluronic acid (oHA), disulfide bond, and curcumin (Cur), named as TPP-oHA-S-S-Cur. The TPP targeted the mitochondria, the antitumor drug Cur served as a hydrophobic core, the CD44 receptor targeting oHA worked as a hydrophilic shell, and the disulfide bond acted as a connecting arm. The chemical structure of TPP-oHA-S-S-Cur was characterized by 1HNMR technology. Cur was loaded into the TPP-oHA-S-S-Cur micelles by self-assembly. Some properties, including the preparation of micelles, morphology, redox sensitivity, and mitochondrial targeting, were studied. The results showed that TPP-oHA-S-S-Cur micelles had a mean diameter of 122.4 ± 23.4 nm, zeta potential - 26.55 ± 4.99 mV. In vitro release study and cellular uptake test showed that TPP-oHA-S-S-Cur micelles had redox sensibility, dual targeting to mitochondrial and CD44 receptor. This work provided a promising smart multifunctional nanocarrier platform to enhance the solubility, decrease the side effects, and improve the therapeutic efficacy of anticancer drugs.

CD44 and Bak expression in IL-6 or TNF-alpha gene knockout mice after whole lung irradiation

International Nuclear Information System (INIS)

Sakai, Minako; Iwakawa, Mayumi; Ohta, Toshie; Tsujii, Hirohiko; Imai, Takashi; Iwakura, Yoichiro

2008-01-01

To understand the molecular mechanisms that underlie radiation pneumonitis, we examined whether knockout of the tumor necrosis factor (TNF) or the interleukin (IL)-6 gene could give mice an inherent resistance to radiation in the acute phase of alveolar damage after thoracic irradiation. The temporal expression of inflammation (CD44) and apoptosis (Bak) markers in lung after thoracic irradiation was measured to determine the degree of alveolar damage. At 4 weeks post-irradiation (10 Gy), small inflammatory foci were observed in all mice, but there were no obvious histological differences between control (C57BL/6JSlc), TNF-alpha knockout (TNF KO), and IL-6 knockout (IL-6 KO) mice. However, immunohistochemical analysis of CD44 and Bak expression over a time course of 2 weeks highlighted significant differences between the three groups. C57BL/6JSlc and TNF KO mice had increased numbers of both CD44-positive and Bak-positive cells after irradiation, while the IL-6 KO mice showed stable levels of CD44 and Bak. In conclusion, the radioresistant status of IL-6 KO mice in the acute phase of alveolar damage after irradiation suggested an important role for IL-6 in radiation pneumonitis. (author)

WNT5A inhibits metastasis and alters splicing of Cd44 in breast cancer cells.

Directory of Open Access Journals (Sweden)

Wen Jiang

Full Text Available Wnt5a is a non-canonical signaling Wnt. Low expression of WNT5A is correlated with poor prognosis in breast cancer patients. The highly invasive breast cancer cell lines, MDA-MB-231 and 4T1, express very low levels of WNT5A. To determine if enhanced expression of WNT5A would affect metastatic behavior, we generated WNT5A expressing cells from the 4T1 and MDA-MB-231 parental cell lines. WNT5A expressing cells demonstrated cobblestone morphology and reduced in vitro migration relative to controls. Cell growth was not altered. Metastasis to the lung via tail vein injection was reduced in the 4T1-WNT5A expressing cells relative to 4T1-vector controls. To determine the mechanism of WNT5A action on metastasis, we performed microarray and whole-transcriptome sequence analysis (RNA-seq to compare gene expression in 4T1-WNT5A and 4T1-vector cells. Analysis indicated highly significant alterations in expression of genes associated with cellular movement. Down-regulation of a subset of these genes, Mmp13, Nos2, Il1a, Cxcl2, and Lamb3, in WNT5A expressing cells was verified by semi-quantitative RT-PCR. Significant differences in transcript splicing were also detected in cell movement associated genes including Cd44. Cd44 is an adhesion molecule with a complex genome structure. Variable exon usage is associated with metastatic phenotype. Alternative spicing of Cd44 in WNT5A expressing cells was confirmed using RT-PCR. We conclude that WNT5A inhibits metastasis through down-regulation of multiple cell movement pathways by regulating transcript levels and splicing of key genes like Cd44.

Entropy-based model for miRNA isoform analysis.

Directory of Open Access Journals (Sweden)

Shengqin Wang

Full Text Available MiRNAs have been widely studied due to their important post-transcriptional regulatory roles in gene expression. Many reports have demonstrated the evidence of miRNA isoform products (isomiRs in high-throughput small RNA sequencing data. However, the biological function involved in these molecules is still not well investigated. Here, we developed a Shannon entropy-based model to estimate isomiR expression profiles of high-throughput small RNA sequencing data extracted from miRBase webserver. By using the Kolmogorov-Smirnov statistical test (KS test, we demonstrated that the 5p and 3p miRNAs present more variants than the single arm miRNAs. We also found that the isomiR variant, except the 3' isomiR variant, is strongly correlated with Minimum Free Energy (MFE of pre-miRNA, suggesting the intrinsic feature of pre-miRNA should be one of the important factors for the miRNA regulation. The functional enrichment analysis showed that the miRNAs with high variation, particularly the 5' end variation, are enriched in a set of critical functions, supporting these molecules should not be randomly produced. Our results provide a probabilistic framework for miRNA isoforms analysis, and give functional insights into pre-miRNA processing.

Expression and distribution of hyaluronic acid and CD44 in unphonated human vocal fold mucosa.

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Sato, Kiminori; Umeno, Hirohito; Nakashima, Tadashi; Nonaka, Satoshi; Harabuchi, Yasuaki

2009-11-01

The tension caused by phonation (vocal fold vibration) is hypothesized to stimulate vocal fold stellate cells (VFSCs) in the maculae flavae (MFe) to accelerate production of extracellular matrices. The distribution of hyaluronic acid (HA) and expression of CD44 (a cell surface receptor for HA) were examined in human vocal fold mucosae (VFMe) that had remained unphonated since birth. Five specimens of VFMe (3 adults, 2 children) that had remained unphonated since birth were investigated with Alcian blue staining, hyaluronidase digestion, and immunohistochemistry for CD44. The VFMe containing MFe were hypoplastic and rudimentary. The VFMe did not have a vocal ligament, Reinke's space, or a layered structure, and the lamina propria appeared as a uniform structure. In the children, HA was distributed in the VFMe containing MFe. In the adults, HA had decreased in the VFMe containing MFe. In both groups, the VFSCs in the MFe and the fibroblasts in the lamina propria expressed little CD44. This study supports the hypothesis that the tensions caused by vocal fold vibration stimulate the VFSCs in the MFe to accelerate production of extracellular matrices and form the layered structure. Phonation after birth is one of the important factors in the growth and development of the human VFMe.

An Analysis of Trafficking Receptors Shows that CD44 and P-Selectin Glycoprotein Ligand-1 Collectively Control the Migration of Activated Human T-Cells

KAUST Repository

Ali, Amal J.

2017-05-03

Selectins guide the traffic of activated T-cells through the blood stream by mediating their tethering and rolling onto inflamed endothelium, in this way acting as beacons to help navigate them to sites of inflammation. Here, we present a comprehensive analysis of E-selectin ligands expressed on activated human T-cells. We identified several novel glycoproteins that function as E-selectin ligands. Specifically, we compared the role of P-selectin glycoprotein ligand-1 (PSGL-1) and CD43, known E-selectin ligands, to CD44, a ligand that has not previously been characterized as an E-selectin ligand on activated human T-cells. We showed that CD44 acts as a functional E-selectin ligand when expressed on both CD4+ and CD8+ T-cells. Moreover, the CD44 protein carries a binding epitope identifying it as hematopoietic cell E- and/or L-selectin ligand (HCELL). Furthermore, by knocking down these ligands individually or together in primary activated human T-cells, we demonstrated that CD44/HCELL, and not CD43, cooperates with PSGL-1 as a major E-selectin ligand. Additionally, we demonstrated the relevance of our findings to chronic autoimmune disease, by showing that CD44/HCELL and PSGL-1, but not CD43, from T-cells isolated from psoriasis patients, bind E-selectin.

Unveiling the role of PAK2 in CD44 mediated inhibition of proliferation, differentiation and apoptosis in AML cells

KAUST Repository

Aldehaiman, Mansour M.

2018-04-01

Acute myeloid leukemia (AML) is a heterogeneous disease characterized by the accumulation of immature nonfunctional highly proliferative hematopoietic cells in the blood, due to a blockage in myeloid differentiation at various stages. Since the success of the differentiation agent, All-trans retinoic acid (ATRA), in the treatment of acute promyelocytic leukemia (APL), much effort has gone into trying to find agents that are able to differentiate AML cells and specifically the leukemic stem cell (LSC). CD44 is a cell surface receptor that is over-expressed on AML cells. When bound to anti-CD44 monoclonal antibodies (mAbs), this differentiation block is relieved in AML cells and their proliferation is reduced. The molecular mechanisms that AML cells undergo to achieve this reversal of their apparent phenotype is not fully understood. To this end, we designed a study using quantitative phosphoproteomics approaches aimed at identifying differences in phosphorylation found on proteins involved in signaling pathways post-treatment with CD44-mAbs. The Rho family of GTPases emerged as one of the most transformed pathways following the treatment with CD44-mAbs. The P21 activated kinase 2(PAK2), a target of the Rho family of GTPases, was found to be differentially phosphorylated in AML cells post-treatment with CD44-mAbs. This protein has been found to possess a role similar to that of a switch that determines whether the cell survives or undergoes apoptosis. Beyond confirming these results by various biochemical approaches, our study aimed to determine the effect of knock down of PAK2 on AML cell proliferation and differentiation. In addition, over-expression of PAK2 mutants using plasmid cloning was also explored to fully understand how levels of PAK2 as well as the alteration of specific phospohorylation sites could alter AML cell responses to CD44-mAbs. Results from this study will be important in determining whether PAK2 could be used as a potential therapeutic target

Selective regain of egfr gene copies in CD44+/CD24-/low breast cancer cellular model MDA-MB-468

International Nuclear Information System (INIS)

Agelopoulos, Konstantin; Buerger, Horst; Brandt, Burkhard; Greve, Burkhard; Schmidt, Hartmut; Pospisil, Heike; Kurtz, Stefan; Bartkowiak, Kai; Andreas, Antje; Wieczorek, Marek; Korsching, Eberhard

2010-01-01

Increased transcription of oncogenes like the epidermal growth factor receptor (EGFR) is frequently caused by amplification of the whole gene or at least of regulatory sequences. Aim of this study was to pinpoint mechanistic parameters occurring during egfr copy number gains leading to a stable EGFR overexpression and high sensitivity to extracellular signalling. A deeper understanding of those marker events might improve early diagnosis of cancer in suspect lesions, early detection of cancer progression and the prediction of egfr targeted therapies. The basal-like/stemness type breast cancer cell line subpopulation MDA-MB-468 CD44 high /CD24 -/low , carrying high egfr amplifications, was chosen as a model system in this study. Subclones of the heterogeneous cell line expressing low and high EGF receptor densities were isolated by cell sorting. Genomic profiling was carried out for these by means of SNP array profiling, qPCR and FISH. Cell cycle analysis was performed using the BrdU quenching technique. Low and high EGFR expressing MDA-MB-468 CD44 + /CD24 -/low subpopulations separated by cell sorting showed intermediate and high copy numbers of egfr, respectively. However, during cell culture an increase solely for egfr gene copy numbers in the intermediate subpopulation occurred. This shift was based on the formation of new cells which regained egfr gene copies. By two parametric cell cycle analysis clonal effects mediated through growth advantage of cells bearing higher egfr gene copy numbers could most likely be excluded for being the driving force. Subsequently, the detection of a fragile site distal to the egfr gene, sustaining uncapped telomere-less chromosomal ends, the ladder-like structure of the intrachromosomal egfr amplification and a broader range of egfr copy numbers support the assumption that dynamic chromosomal rearrangements, like breakage-fusion-bridge-cycles other than proliferation drive the gain of egfr copies. Progressive genome modulation

Absent/weak CD44 intensity and positive human papillomavirus (HPV) status in oropharyngeal squamous cell carcinoma indicates a very high survival

International Nuclear Information System (INIS)

Näsman, Anders; Nordfors, Cecilia; Grün, Nathalie; Munck-Wikland, Eva; Ramqvist, Torbjörn; Marklund, Linda; Lindquist, David; Dalianis, Tina

2013-01-01

Patients with human papillomavirus DNA positive (HPV DNA +) oropharyngeal squamous cell carcinoma (OSCC) have better clinical outcome than those with HPV DNA negative (HPV DNA −) OSCC upon intensive oncological treatment. All HPV DNA + OSCC patients may not require intensive treatment, however, but before potentially deintensifying treatment, additional predictive markers are needed. Here, we examined HPV, p16 INK4a , and CD44 in OSCC in correlation to clinical outcome. Pretreatment tumors from 290 OSCC patients, the majority not receiving chemotherapy, were analyzed for HPV DNA by Luminex and for p16 INK4a and CD44 by immunohistochemistry. 225/290 (78%) tumors were HPV DNA + and 211/290 (73%) overexpressed p16 INK4a , which correlated to presence of HPV (P < 0.0001). Presence of HPV DNA, absent/weak CD44 intensity staining correlated to favorable 3-year disease-free survival (DFS) and overall survival (OS) by univariate and multivariate analysis, and likewise for p16 INK4a by univariate analysis. Upon stratification for HPV, HPV DNA + OSCC with absent/weak CD44 intensity presented the significantly best 3-year DFS and OS, with >95% 3-year DFS and OS. Furthermore, in HPV DNA + OSCC, p16 INK4a + overexpression correlated to a favorable 3-year OS. In conclusion, patients with HPV DNA + and absent/weak CD44 intensity OSCC presented the best survival and this marker combination could possibly be used for selecting patients for tailored deintensified treatment in prospective clinical trials. Absence of/weak CD44 or presence of human papillomavirus (HPV) DNA was shown as a favorable prognostic factors in tonsillar and tongue base cancer. Moreover, patients with the combination of absence of/weak CD44 and presence of HPV DNA presented a very favorable outcome. Therefore, we suggest that this marker combination could potentially be used to single out patients with a high survival that could benefit from a de-escalated oncological treatment

The Role of Fatty Acid Metabolism in Estrogen Receptor Negative Breast Cancer

Science.gov (United States)

2015-11-01

of a novel variant of isoform 6. Biochemistry 44 (5), 1635–1642. [31] Mashima T, Sato S, Okabe S, Miyata S, Matsuura M, Sugimoto Y, et al. (2009). Acyl... AMP and p38 mitogen-activated protein kinase.World J Gastroenterol 11, 2557–2563. [50] Sung KY, Hwang SY, Park MK, Bae HI, Kim WH, Kim JC, et al. (2003...Recombinant Long-Chain Rat Acyl-CoA Synthetase Isoforms 3 and 6: Identification of a Novel Variant of Isoform 6. Biochemistry 44: 1635-1642. doi:10.1021

Galunisertib suppresses the staminal phenotype in hepatocellular carcinoma by modulating CD44 expression.

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Rani, Bhavna; Malfettone, Andrea; Dituri, Francesco; Soukupova, Jitka; Lupo, Luigi; Mancarella, Serena; Fabregat, Isabel; Giannelli, Gianluigi

2018-03-07

Cancer stem cells (CSCs) niche in the tumor microenvironment is responsible for cancer recurrence and therapy failure. To better understand its molecular and biological involvement in hepatocellular carcinoma (HCC) progression, one can design more effective therapies and tailored then to individual patients. While sorafenib is currently the only approved drug for first-line treatment of advanced stage HCC, its role in modulating the CSC niche is estimated to be small. By contrast, transforming growth factor (TGF)-β pathway seems to influence the CSC and thus may impact hallmarks of HCC, such as liver fibrosis, cirrhosis, and tumor progression. Therefore, blocking this pathway may offer an appealing and druggable target. In our study, we have used galunisertib (LY2157299), a selective ATP-mimetic inhibitor of TGF-β receptor I (TGFβI/ALK5) activation, currently under clinical investigation in HCC patients. Because the drug resistance is mainly mediated by CSCs, we tested the effects of galunisertib on stemness phenotype in HCC cells to determine whether TGF-β signaling modulates CSC niche and drug resistance. Galunisertib modulated the expression of stemness-related genes only in the invasive (HLE and HLF) HCC cells inducing a decreased expression of CD44 and THY1. Furthermore, galunisertib also reduced the stemness-related functions of invasive HCC cells decreasing the formation of colonies, liver spheroids and invasive growth ability. Interestingly, CD44 loss of function mimicked the galunisertib effects on HCC stemness-related functions. Galunisertib treatment also reduced the expression of stemness-related genes in ex vivo human HCC specimens. Our observations are the first evidence that galunisertib effectiveness overcomes stemness-derived aggressiveness via decreased expression CD44 and THY1.

A hyaluronic acid-based hydrogel enabling CD44-mediated chondrocyte binding and gapmer oligonucleotide release for modulation of gene expression in osteoarthritis

DEFF Research Database (Denmark)

Cai, Yunpeng; López-Ruiz, Elena; Wengel, Jesper

2017-01-01

Hyaluronic acid (HA) is an attractive biomaterial for osteoarthritis (OA) treatment due to inherent functional and compatibility properties as an endogenous knee joint component. In this work, we describe a HA-based hydrogel with the dual functionality of increased CD44-dependent chondrocyte......:3) for identifying designs displaying optimal engagement of OA patient-derived CD44-expressing chondrocytes. Correlation was found between cell binding and CD44 expression, with maximal binding exhibited at a HA/chitosan ratio of 7:3, that was 181% higher than CD44-negative MCF-7 cell control cells. Transfection...... agent-free uptake into OA chondrocytes of fluorescent 13-mer DNA oligonucleotides with a flanked locked nucleic acid (LNA) gapmer design, in contrast to naked siRNA, was demonstrated by confocal and flow cytometric analysis. A sustained and complete release over 5days was found with the 7:3 hydrogel...

Dual-targeting hybrid nanoparticles for the delivery of SN38 to Her2 and CD44 overexpressed human gastric cancer

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Yang, Zhe; Luo, Huiyan; Cao, Zhong; Chen, Ya; Gao, Jinbiao; Li, Yingqin; Jiang, Qing; Xu, Ruihua; Liu, Jie

2016-06-01

Gastric cancer (GC), particularly of the type with high expression of both human epidermal growth factor receptor 2 (Her2) and cluster determinant 44 (CD44), is one of the most malignant human tumors which causes a high mortality rate due to rapid tumor growth and metastasis. To develop effective therapeutic treatments, a dual-targeting hybrid nanoparticle (NP) system was designed and constructed to deliver the SN38 agent specifically to human solid gastric tumors bearing excessive Her2 and CD44. The hybrid NPs consist of a particle core made of the biodegradable polymer PLGA and a lipoid shell prepared by conjugating the AHNP peptides and n-hexadecylamine (HDA) to the carboxyl groups of hyaluronic acid (HA). Upon encapsulation of the SN38 agent in the NPs, the AHNP peptides and HA on the NP surface allow preferential delivery of the drug to gastric cancer cells (e.g., HGC27 cells) by targeting Her2 and CD44. Cellular uptake and in vivo biodistribution experiments verified the active targeting and prolonged in vivo circulation properties of the dual-targeting hybrid NPs, leading to enhanced accumulation of the drug in tumors. Furthermore, the anti-proliferation mechanism studies revealed that the inhibition of the growth and invasive activity of HGC27 cells was not only attributed to the enhanced cellular uptake of dual-targeting NPs, but also benefited from the suppression of CD44 and Her2 expression by HA and AHNP moieties. Finally, intravenous administration of the SN38-loaded dual-targeting hybrid NPs induced significant growth inhibition of HGC27 tumor xenografted in nude mice compared with a clinical antitumor agent, Irinotecan (CPT-11), and the other NP formulations. These results demonstrate that the designed dual-targeting hybrid NPs are promising for targeted anti-cancer drug delivery to treat human gastric tumors over-expressing Her2 and CD44.Gastric cancer (GC), particularly of the type with high expression of both human epidermal growth factor receptor

Targeted delivery of CD44s-siRNA by ScFv overcomes de novo resistance to cetuximab in triple negative breast cancer.

Science.gov (United States)

Fu, Wenyan; Sun, Hefen; Zhao, Yang; Chen, Mengting; Yang, Lipeng; Yang, Xueli; Jin, Wei

2018-05-16

The overexpression of EGFR often occurs in TNBC, and the anti-EGFR receptor antibody cetuximab is used widely to treat metastatic cancer in the clinic. However, EGFR-targeted therapies have been developed for TNBC without clinical success. In this study, we show that impaired EGFR degradation is crucial for resistance to cetuximab, which depends on the cell surface molecule CD44. To further investigate the role of CD44 in EGFR signaling and its treatment potential, we developed a targeting fusion protein composed of an anti-EGFR scFv generated from cetuximab and truncated protamine, called Ce-tP. CD44 siRNA can be specifically delivered into EGFR-positive TNBC cells by Ce-tP. Efficient knockdown of CD44 and suppression of both EGFR and downstream signaling by the Ce-tP/siRNA complex were observed in EGFR-positive TNBC cells. More importantly, our results also showed that targeted delivery of siRNA specific for CD44 can efficiently overcome resistance to EGFR targeting in TNBC cells both in vitro and in vivo. Overall, our results establish a new principle to achieve EGFR inhibition in TNBC and limit drug resistance. Copyright © 2018 Elsevier Ltd. All rights reserved.

Differential control of ageing and lifespan by isoforms and splice variants across the mTOR network.

Science.gov (United States)

Razquin Navas, Patricia; Thedieck, Kathrin

2017-07-15

Ageing can be defined as the gradual deterioration of physiological functions, increasing the incidence of age-related disorders and the probability of death. Therefore, the term ageing not only reflects the lifespan of an organism but also refers to progressive functional impairment and disease. The nutrient-sensing kinase mTOR (mammalian target of rapamycin) is a major determinant of ageing. mTOR promotes cell growth and controls central metabolic pathways including protein biosynthesis, autophagy and glucose and lipid homoeostasis. The concept that mTOR has a crucial role in ageing is supported by numerous reports on the lifespan-prolonging effects of the mTOR inhibitor rapamycin in invertebrate and vertebrate model organisms. Dietary restriction increases lifespan and delays ageing phenotypes as well and mTOR has been assigned a major role in this process. This may suggest a causal relationship between the lifespan of an organism and its metabolic phenotype. More than 25 years after mTOR's discovery, a wealth of metabolic and ageing-related effects have been reported. In this review, we cover the current view on the contribution of the different elements of the mTOR signalling network to lifespan and age-related metabolic impairment. We specifically focus on distinct roles of isoforms and splice variants across the mTOR network. The comprehensive analysis of mouse knockout studies targeting these variants does not support a tight correlation between lifespan prolongation and improved metabolic phenotypes and questions the strict causal relationship between them. © 2017 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.

Hyaluronan-induced masking of ErbB2 and CD44-enhanced trastuzumab internalisation in trastuzumab resistant breast cancer.

Science.gov (United States)

Pályi-Krekk, Zsuzsanna; Barok, Márk; Isola, Jorma; Tammi, Markku; Szöllosi, János; Nagy, Peter

2007-11-01

Although trastuzumab, a recombinant humanised anti-ErbB2 antibody, is widely used in the treatment of breast cancer, neither its mechanism of action, nor the factors leading to resistance are fully understood. We have previously shown that antibody-dependent cellular cytotoxicity is pivotal in the in vivo effect of trastuzumab against JIMT-1, a cell line showing in vitro resistance to the antibody, and suggested that masking of the trastuzumab-binding epitope by MUC-4, a cell surface mucin, took place. Here, we further explored the role of masking of ErbB2 in connection with CD44 expression and synthesis of its ligand, hyaluronan. We show that high expression of CD44 observed in JIMT-1 cells correlates with ErbB2 downregulation in vivo, while siRNA-mediated inhibition of CD44 expression leads to decreased rate of trastuzumab internalisation and low cell proliferation in vitro. An inhibitor of hyaluronan synthesis, 4-methylumbelliferon (4-MU) significantly reduced the hyaluronan level of JIMT-1 cells both in vivo and in vitro leading to enhanced binding of trastuzumab to ErbB2 and increased ErbB2 down-regulation. Furthermore, the inhibitory effect of trastuzumab on the growth of JIMT-1 xenografts was significantly increased by 4-MU treatment. Our results point to the importance of the CD44-hyaluronan pathway in the escape of tumour cells from receptor-oriented therapy.

Direct demonstration of the infiltration of murine central nervous system by Pgp-1/CD44high CD45RB(low) CD4+ T cells that induce experimental allergic encephalomyelitis

DEFF Research Database (Denmark)

Zeine, R; Owens, T

1992-01-01

-labelled CD4+ cells isolated from the CNS were responsive to MBP in vitro, whereas PKH2+ CD4+ cells from lymph nodes showed almost undetectable responses. In control experiments in which ovalbumin (OVA)-reactive T cells were transferred, a small number of fluorescent-labelled CD4+ T cells were also......In experimental allergic encephalomyelitis (EAE), autoimmune T cells infiltrate the central nervous system (CNS) and initiate demyelinating pathology. We have used flow cytometry to directly analyse the migration to the CNS of MBP-reactive CD4+ T cells labelled with a lipophilic fluorescent dye...... (PKH2), in SJL/J mice with passively transferred EAE. Labelled cells constituted about 45% of the CNS CD4+ population at the time of EAE onset. Almost all (greater than 90%) of the PKH2-labelled CD4+ T cells from EAE CNS were blasts and were alpha/beta T cell receptor (TCR)+, CD44(Pgp-1)high...

Clinically relevant morphological structures in breast cancer represent transcriptionally distinct tumor cell populations with varied degrees of epithelial-mesenchymal transition and CD44+CD24- stemness.

Science.gov (United States)

Denisov, Evgeny V; Skryabin, Nikolay A; Gerashchenko, Tatiana S; Tashireva, Lubov A; Wilhelm, Jochen; Buldakov, Mikhail A; Sleptcov, Aleksei A; Lebedev, Igor N; Vtorushin, Sergey V; Zavyalova, Marina V; Cherdyntseva, Nadezhda V; Perelmuter, Vladimir M

2017-09-22

Intratumor morphological heterogeneity in breast cancer is represented by different morphological structures (tubular, alveolar, solid, trabecular, and discrete) and contributes to poor prognosis; however, the mechanisms involved remain unclear. In this study, we performed 3D imaging, laser microdissection-assisted array comparative genomic hybridization and gene expression microarray analysis of different morphological structures and examined their association with the standard immunohistochemistry scorings and CD44 + CD24 - cancer stem cells. We found that the intratumor morphological heterogeneity is not associated with chromosomal aberrations. By contrast, morphological structures were characterized by specific gene expression profiles and signaling pathways and significantly differed in progesterone receptor and Ki-67 expression. Most importantly, we observed significant differences between structures in the number of expressed genes of the epithelial and mesenchymal phenotypes and the association with cancer invasion pathways. Tubular (tube-shaped) and alveolar (spheroid-shaped) structures were transcriptionally similar and demonstrated co-expression of epithelial and mesenchymal markers. Solid (large shapeless) structures retained epithelial features but demonstrated an increase in mesenchymal traits and collective cell migration hallmarks. Mesenchymal genes and cancer invasion pathways, as well as Ki-67 expression, were enriched in trabecular (one/two rows of tumor cells) and discrete groups (single cells and/or arrangements of 2-5 cells). Surprisingly, the number of CD44 + CD24 - cells was found to be the lowest in discrete groups and the highest in alveolar and solid structures. Overall, our findings indicate the association of intratumor morphological heterogeneity in breast cancer with the epithelial-mesenchymal transition and CD44 + CD24 - stemness and the appeal of this heterogeneity as a model for the study of cancer invasion.

Targeting Tumor Cells with Anti-CD44 Antibody Triggers Macrophage-Mediated Immune Modulatory Effects in a Cancer Xenograft Model.

Science.gov (United States)

Maisel, Daniela; Birzele, Fabian; Voss, Edgar; Nopora, Adam; Bader, Sabine; Friess, Thomas; Goller, Bernhard; Laifenfeld, Daphna; Weigand, Stefan; Runza, Valeria

2016-01-01

CD44, a transmembrane receptor reported to be involved in various cellular functions, is overexpressed in several cancer types and supposed to be involved in the initiation, progression and prognosis of these cancers. Since the sequence of events following the blockage of the CD44-HA interaction has not yet been studied in detail, we profiled xenograft tumors by RNA Sequencing to elucidate the mode of action of the anti-CD44 antibody RG7356. Analysis of tumor and host gene-expression profiles led us to the hypothesis that treatment with RG7356 antibody leads to an activation of the immune system. Using cytokine measurements we further show that this activation involves the secretion of chemo-attractants necessary for the recruitment of immune cells (i.e. macrophages) to the tumor site. We finally provide evidence for antibody-dependent cellular phagocytosis (ADCP) of the malignant cells by macrophages.

Targeting Tumor Cells with Anti-CD44 Antibody Triggers Macrophage-Mediated Immune Modulatory Effects in a Cancer Xenograft Model.

Directory of Open Access Journals (Sweden)

Daniela Maisel

Full Text Available CD44, a transmembrane receptor reported to be involved in various cellular functions, is overexpressed in several cancer types and supposed to be involved in the initiation, progression and prognosis of these cancers. Since the sequence of events following the blockage of the CD44-HA interaction has not yet been studied in detail, we profiled xenograft tumors by RNA Sequencing to elucidate the mode of action of the anti-CD44 antibody RG7356. Analysis of tumor and host gene-expression profiles led us to the hypothesis that treatment with RG7356 antibody leads to an activation of the immune system. Using cytokine measurements we further show that this activation involves the secretion of chemo-attractants necessary for the recruitment of immune cells (i.e. macrophages to the tumor site. We finally provide evidence for antibody-dependent cellular phagocytosis (ADCP of the malignant cells by macrophages.

Cellular endocytic compartment localization of expressed canine CD1 molecules

DEFF Research Database (Denmark)

Schjærff, Mette; Keller, Stefan M.; Affolter, Verena K.

2016-01-01

CD1 molecules are glycoproteins present primarily on dendritic cells (DCs), which recognize and presenta variety of foreign- and self-lipid antigens to T-cells. Humans have five different CD1 isoforms that sur-vey distinct cellular compartments allowing for recognition of a large repertoire...... onlya diminished GFP expression. In conclusion, canine CD1 transfectants show distinct localization patternsthat are similar to human CD1 proteins with the exception of the canine CD1d isoform, which most likelyis non-functional. These findings imply that canine CD1 localization overall resembles human...... CD1 traf-ficking patterns. This knowledge is important for the understanding of lipid antigen-receptor immunityin the dog....

Proteomic Analysis of Parkin Isoforms Expression in Different Rat Brain Areas.

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D'Amico, Agata Grazia; Maugeri, Grazia; Reitano, Rita; Cavallaro, Sebastiano; D'Agata, Velia

2016-10-01

PARK2 gene's mutations are related to the familial form of juvenile Parkinsonism, also known as the autosomic recessive juvenile Parkinsonism. This gene encodes for parkin, a 465-amino acid protein. To date, a large number of parkin isoforms, generated by an alternative splicing mechanism, have been described. Currently, Gene Bank lists 27 rat PARK2 transcripts, which matches to 20 exclusive parkin alternative splice variants. Despite the existence of these isoforms, most of the studies carried out so far, have been focused only on the originally cloned parkin. In this work we have analyzed the expression profile of parkin isoforms in some rat brain areas including prefrontal cortex, hippocampus, substantia nigra and cerebellum. To discriminate among these isoforms, we detected their localization through the use of two antibodies that are able to identify different domains of the parkin canonical sequence. Our analysis has revealed that at least fourteen parkin isoforms are expressed in rat brain with a various distribution in the regions analyzed. Our study might help to elucidate the pathophysiological role of these proteins in the central nervous system.

Characterization of TTN Novex Splicing Variants across Species and the Role of RBM20 in Novex-Specific Exon Splicing

Directory of Open Access Journals (Sweden)

Zhilong Chen

2018-02-01

Full Text Available Titin (TTN is a major disease-causing gene in cardiac muscle. Titin (TTN contains 363 exons in human encoding various sizes of TTN protein due to alternative splicing regulated mainly by RNA binding motif 20 (RBM20. Three isoforms of TTN protein are produced by mutually exclusive exons 45 (Novex 1, 46 (Novex 2, and 48 (Novex 3. Alternatively splicing in Novex isoforms across species and whether Novex isoforms are associated with heart disease remains completely unknown. Cross-species exon comparison with the mVISTA online tool revealed that exon 45 is more highly conserved across all species than exons 46 and 48. Importantly, a conserved region between exons 47 and 48 across species was revealed for the first time. Reverse transcript polymerase chain reaction (RT-PCR and DNA sequencing confirmed a new exon named as 48′ in Novex 3. In addition, with primer pairs for Novex 1, a new truncated form preserving introns 44 and 45 was discovered. We discovered that Novex 2 is not expressed in the pig, mouse, and rat with Novex 2 primer pairs. Unexpectedly, three truncated forms were identified. One TTN variant with intron 46 retention is mainly expressed in the human and frog heart, another variant with co-expression of exons 45 and 46 exists predominantly in chicken and frog heart, and a third with retention of introns 45 and 46 is mainly expressed in pig, mouse, rat, and chicken. Using Rbm20 knockout rat heart, we revealed that RBM20 is not a splicing regulator of Novex variants. Furthermore, the expression levels of Novex variants in human hearts with cardiomyopathies suggested that Novexes 2 and 3 could be associated with dilated cardiomyopathy (DCM and/or arrhythmogenic right ventricular cardiomyopathy (ARVC. Taken together, our study reveals that splicing diversity of Novex exons across species and Novex variants might play a role in cardiomyopathy.

CD and MCD studies of the effects of component B variant binding on the biferrous active site of methane monooxygenase.

Science.gov (United States)

Mitić, Natasa; Schwartz, Jennifer K; Brazeau, Brian J; Lipscomb, John D; Solomon, Edward I

2008-08-12

The multicomponent soluble form of methane monooxygenase (sMMO) catalyzes the oxidation of methane through the activation of O 2 at a nonheme biferrous center in the hydroxylase component, MMOH. Reactivity is limited without binding of the sMMO effector protein, MMOB. Past studies show that mutations of specific MMOB surface residues cause large changes in the rates of individual steps in the MMOH reaction cycle. To define the structural and mechanistic bases for these observations, CD, MCD, and VTVH MCD spectroscopies coupled with ligand-field (LF) calculations are used to elucidate changes occurring near and at the MMOH biferrous cluster upon binding of MMOB and the MMOB variants. Perturbations to both the CD and MCD are observed upon binding wild-type MMOB and the MMOB variant that similarly increases O 2 reactivity. MMOB variants that do not greatly increase O 2 reactivity fail to cause one or both of these changes. LF calculations indicate that reorientation of the terminal glutamate on Fe2 reproduces the spectral perturbations in MCD. Although this structural change allows O 2 to bridge the diiron site and shifts the redox active orbitals for good overlap, it is not sufficient for enhanced O 2 reactivity of the enzyme. Binding of the T111Y-MMOB variant to MMOH induces the MCD, but not CD changes, and causes only a small increase in reactivity. Thus, both the geometric rearrangement at Fe2 (observed in MCD) coupled with a more global conformational change that may control O 2 access (probed by CD), induced by MMOB binding, are critical factors in the reactivity of sMMO.

Genomic organization and the tissue distribution of alternatively spliced isoforms of the mouse Spatial gene

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Mattei Marie-Geneviève

2004-07-01

Full Text Available Abstract Background The stromal component of the thymic microenvironment is critical for T lymphocyte generation. Thymocyte differentiation involves a cascade of coordinated stromal genes controlling thymocyte survival, lineage commitment and selection. The "Stromal Protein Associated with Thymii And Lymph-node" (Spatial gene encodes a putative transcription factor which may be involved in T-cell development. In the testis, the Spatial gene is also expressed by round spermatids during spermatogenesis. Results The Spatial gene maps to the B3-B4 region of murine chromosome 10 corresponding to the human syntenic region 10q22.1. The mouse Spatial genomic DNA is organised into 10 exons and is alternatively spliced to generate two short isoforms (Spatial-α and -γ and two other long isoforms (Spatial-δ and -ε comprising 5 additional exons on the 3' site. Here, we report the cloning of a new short isoform, Spatial-β, which differs from other isoforms by an additional alternative exon of 69 bases. This new exon encodes an interesting proline-rich signature that could confer to the 34 kDa Spatial-β protein a particular function. By quantitative TaqMan RT-PCR, we have shown that the short isoforms are highly expressed in the thymus while the long isoforms are highly expressed in the testis. We further examined the inter-species conservation of Spatial between several mammals and identified that the protein which is rich in proline and positive amino acids, is highly conserved. Conclusions The Spatial gene generates at least five alternative spliced variants: three short isoforms (Spatial-α, -β and -γ highly expressed in the thymus and two long isoforms (Spatial-δ and -ε highly expressed in the testis. These alternative spliced variants could have a tissue specific function.

Identification and characterization of novel smoothelin isoforms in vascular smooth muscle.

Science.gov (United States)

Krämer, J; Quensel, C; Meding, J; Cardoso, M C; Leonhardt, H

2001-01-01

Smoothelin is a cytoskeletal protein specifically expressed in differentiated smooth muscle cells and has been shown to colocalize with smooth muscle alpha actin. In addition to the small smoothelin isoform of 59 kD, we recently identified a large smoothelin isoform of 117 kD. The aim of this study was to identify and characterize novel smoothelin isoforms. The genomic structure and sequence of the smoothelin gene were determined by genomic PCR, RT-PCR and DNA sequencing. Comparison of the cDNA and genomic sequences shows that the small smoothelin isoform is generated by transcription initiation 10 kb downstream of the start site of the large isoform. In addition to the known smoothelin cDNA (c1 isoform) we identified two novel cDNA variants (c2 and c3 isoform) that are generated by alternative splicing within a region, which shows similarity to the spectrin family of F-actin cross-linking proteins. Visceral organs express the c1 form, while the c2 form prevails in well-vascularized tissue as analyzed by RT-PCR. We then generated specific antibodies against the major smoothelin isoforms and could show by Western blotting and immunohistochemistry that the large isoform is specifically expressed in vascular smooth muscle cells, while the small isoform is abundant in visceral smooth muscle. These results strongly suggest that the smoothelin gene contains a vascular and a visceral smooth muscle promoter. The cell-type-specific expression of smoothelin isoforms that are associated with actin filaments may play a role in the modulation of the contractile properties of different smooth muscle cell types. Copyright 2001 S. Karger AG, Basel

Expression profiles of cancer stem cell markers: CD133, CD44, Musashi-1 and EpCAM in the cardiac mucosa-Barrett's esophagus-early esophageal adenocarcinoma-advanced esophageal adenocarcinoma sequence.

Science.gov (United States)

Mokrowiecka, Anna; Veits, Lothar; Falkeis, Christina; Musial, Jacek; Kordek, Radzislaw; Lochowski, Mariusz; Kozak, Jozef; Wierzchniewska-Lawska, Agnieszka; Vieth, Michael; Malecka-Panas, Ewa

2017-03-01

Barrett's esophagus (BE), which develops as a result of gastroesophageal reflux disease, is a preneoplastic condition for esophageal adenocarcinoma (EAC). A new hypothesis suggests that cancer is a disease of stem cells, however, their expression and pathways in BE - EAC sequence are not fully elucidated yet. We used a panel of putative cancer stem cells markers to identify stem cells in consecutive steps of BE-related cancer progression. Immunohistochemistry was performed on formalin-fixed, paraffin-embedded blocks from 58 patients with normal cardiac mucosa (n=5), BE (n=14), early EAC (pT1) from mucosal resection (n=17) and advanced EAC (pT1-T4) from postoperative specimens (n=22). Expression of the CD133, CD44, Musashi-1 and EpCAM was analyzed using respective monoclonal antibodies. All markers showed a heterogeneous expression pattern, mainly at the base of the crypts of Barrett's epithelium and EAC, with positive stromal cells in metaplastic and dysplastic lesions. Immuno-expression of EpCAM, CD44 and CD133 in cardiac mucosa was significantly lower (mean immunoreactivity score (IRS)=1.2; 0.0; 0.4; respectively) compared to their expression in Barrett's metaplasia (mean IRS=4.3; 0.14; 0.7; respectively), in early adenocarcinoma (mean IRS=4.4; 0.29; 1.3; respectively) and in advanced adenocarcinoma (mean IRS=6.6; 0.7; 2.7; respectively) (p<0.05). On the contrary, Musashi-1 expression was higher in BE and early ADC compared to GM and advanced ADC (NS). Our results suggest that the stem cells could be present in premalignant lesions. EpCAM, CD44 and CD133 expression could be candidate markers for BE progression, whereas Musashi-1 may be a marker of the small intestinal features of Barrett's mucosa. Copyright © 2016 Elsevier GmbH. All rights reserved.

High-throughput proteomics detection of novel splice isoforms in human platelets.

LENUS (Irish Health Repository)

Power, Karen A

2009-01-01

Alternative splicing (AS) is an intrinsic regulatory mechanism of all metazoans. Recent findings suggest that 100% of multiexonic human genes give rise to splice isoforms. AS can be specific to tissue type, environment or developmentally regulated. Splice variants have also been implicated in various diseases including cancer. Detection of these variants will enhance our understanding of the complexity of the human genome and provide disease-specific and prognostic biomarkers. We adopted a proteomics approach to identify exon skip events - the most common form of AS. We constructed a database harboring the peptide sequences derived from all hypothetical exon skip junctions in the human genome. Searching tandem mass spectrometry (MS\\/MS) data against the database allows the detection of exon skip events, directly at the protein level. Here we describe the application of this approach to human platelets, including the mRNA-based verification of novel splice isoforms of ITGA2, NPEPPS and FH. This methodology is applicable to all new or existing MS\\/MS datasets.

Molecular mechanism for the action of the anti-CD44 monoclonal antibody MEM-85

Czech Academy of Sciences Publication Activity Database

Škerlová, Jana; Král, V.; Kachala, M.; Fábry, M.; Bumba, L.; Svergun, D. I.; Tošner, Z.; Veverka, Václav; Řezáčová, Pavlína

2015-01-01

Roč. 191, č. 2 (2015), s. 214-223 ISSN 1047-8477 R&D Projects: GA MŠk(CZ) LK11205; GA MŠk(CZ) LO1304 Institutional support: RVO:61388963 Keywords : CD44 * epitope mapping * monoclonal antibody * MEM-85 * NMR * SAXS Subject RIV: CE - Biochemistry Impact factor: 2.570, year: 2015

Identification of alternatively spliced isoforms of interleukin-2/15 receptor β chain in ducks.

Science.gov (United States)

Jeong, Jipseol; Kim, Woo H; Yeo, Jaeseung; Fernandez, Cherry P; Kim, Suk; Lee, Youn-Jeong; Lillehoj, Hyun S; Min, Wongi

2014-12-15

Interleukin (IL)-2 and IL-15 receptor β (IL-2/15Rβ, CD122) play important roles in signal transduction for biological functions of IL-2 and IL-15. We found that ducks possess three different IL-2/15Rβ transcripts, a conventional form (duIL-2/15Rβ) and two variants. Comparisons between the cDNA and genomic sequences revealed that the two variants, duIL-2/15Rβ-d7 and duIL-2/15Rβ-d9, were novel spliced transcripts resulting from skipping exons 7 and 9, respectively. Expression profiles of duIL-2/15Rβ and its isoforms were examined in healthy tissues, concanavalin A (ConA)-stimulated splenic lymphocytes and in livers and spleens of Riemerella anatipestifer-infected ducks using quantitative real-time PCR (qRT-PCR). Generally, duIL-2/15Rβ-d9 expression was undetectable in healthy tissues, ConA-activated samples, and R. anatipestifer-infected ducks. Expression levels of duIL-2/15Rβ transcript were relatively high to moderate in all healthy tissues tested, while duIL-2/15Rβ-d7 expression was low. Compared to untreated controls, expression levels of duIL-2/15Rβ were elevated in ConA-activated splenic lymphocytes and in livers on day 7 in R. anatipestifer-infected ducks, while duIL-2/15Rβ-d7 expression was unchanged. Additionally, COS-7 cells transfected with duIL-2/15Rβ, duIL-2/15Rβ-d7, or duIL-2/15Rβ-d9 constructs generated 73 kilodalton (kDa), 31kDa, and 40kDa proteins, respectively. This study identified three different IL-2/15Rβ transcripts, including two isoforms generated by alternative splicing and their gene expression patterns in stimulated conditions. Copyright © 2014 Elsevier B.V. All rights reserved.

Evolution of the cAMP-dependent protein kinase (PKA catalytic subunit isoforms.

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Kristoffer Søberg

Full Text Available The 3',5'-cyclic adenosine monophosphate (cAMP-dependent protein kinase, or protein kinase A (PKA, pathway is one of the most versatile and best studied signaling pathways in eukaryotic cells. The two paralogous PKA catalytic subunits Cα and Cβ, encoded by the genes PRKACA and PRKACB, respectively, are among the best understood model kinases in signal transduction research. In this work, we explore and elucidate the evolution of the alternative 5' exons and the splicing pattern giving rise to the numerous PKA catalytic subunit isoforms. In addition to the universally conserved Cα1/Cβ1 isoforms, we find kinase variants with short N-termini in all main vertebrate classes, including the sperm-specific Cα2 isoform found to be conserved in all mammals. We also describe, for the first time, a PKA Cα isoform with a long N-terminus, paralogous to the PKA Cβ2 N-terminus. An analysis of isoform-specific variation highlights residues and motifs that are likely to be of functional importance.

Oestrogen receptor beta isoform expression in sporadic colorectal cancer, familial adenomatous polyposis and progressive stages of colorectal cancer.

Science.gov (United States)

Stevanato Filho, Paulo Roberto; Aguiar Júnior, Samuel; Begnami, Maria Dirlei; Kuasne, Hellen; Spencer, Ranyell Matheus; Nakagawa, Wilson Toshihiko; Bezerra, Tiago Santoro; Kupper, Bruna Catin; Takahashi, Renata Maymi; Barros Filho, Mateus; Rogatto, Silvia Regina; Lopes, Ademar

2017-11-13

Among the sex hormones, oestrogen may play a role in colorectal cancer, particularly in conjunction with oestrogen receptor-β (ERβ). The expression of ERβ isoform variants and their correlations with familial adenomatous polyposis (FAP) syndrome and sporadic colorectal carcinomas are poorly described. This study aimed to investigate the expression levels of the ERβ1, ERβ2, ERβ4 and ERβ5 isoform variants using quantitative RT-PCR (921 analyses) in FAP, normal mucosa, adenomatous polyps and sporadic colorectal carcinomas. Decreased expression of ERβ isoforms was identified in sporadic polyps and in sporadic colorectal cancer as well as in polyps from FAP syndrome patients compared with normal tissues (p colorectal carcinomas were compared to normal mucosa tissues. These findings suggest an association of the ERβ isoform variants in individuals affected by germline mutations of the APC gene. Progressively decreased expression of ERβ was found in polyps at early stages of low-grade dysplasia, followed by T1-T2 and T3-T4 tumours (p colorectal cancer, the loss of expression was an independent predictor of recurrence, and ERβ1 and ERβ5 expression levels were associated with better disease-free survival (p = 0.002). These findings may provide a better understanding of oestrogens and their potential preventive and therapeutic effects on sporadic colorectal cancer and cancers associated with FAP syndrome.

Relationship of PCNA, C-erbB2 and CD44s expression with tumor grade and stage in urothelial carcinomas of the bladder

Science.gov (United States)

Yıldırım, Ayhan; Kösem, Mustafa; Sayar, İlyas; Gelincik, İbrahim; Yavuz, Alparslan; Bozkurt, Aliseydi; Erkorkmaz, Ünal; Bayram, İrfan

2014-01-01

In the present study, the intention was to reveal the relationship of histological grade and stage with c-erbB2, CD44s, and PCNA immunoreactivity in bladder urothelial carcinomas (UC). In our study, we evaluated 46 items of transurethral resection material of patients submitted by YYU Faculty of Medicine, Main Department of Pathology, with a mass revealed in their bladder after clinical and radiological studies at our laboratories and who were diagnosed with urothelial carcinomas. PCNA, c-erbB2, and CD44s were applied in an immunohistochemical manner comprised from nine low-malignant potential papillary urothelial neoplasia, 23 low-grade papillary urothelial carcinoma, and 14 high-grade papillary urothelial carcinoma. Immunostaining was scored according to the percentage of positive cells. The immunohistochemical study demonstrated that the c-erbB2 and PCNA staining ratio increased when an increase occurred in stage and grade. The CD44s staining ratio decreased. C-erbB2, PCNA, and CD44s appear to be a useful marker in the assessment of the prognosis and treatment options in urothelial carcinomas. PMID:25035774

Development and mechanistic insight into enhanced cytotoxic potential of hyaluronic acid conjugated nanoparticles in CD44 overexpressing cancer cells.

Science.gov (United States)

Saneja, Ankit; Nayak, Debasis; Srinivas, M; Kumar, Amit; Khare, Vaibhav; Katoch, Archana; Goswami, Anindya; Vishwakarma, Ram A; Sawant, Sanghapal D; Gupta, Prem N

2017-01-15

The overexpression of CD44 in cancer cells reroutes number of oncogenic pathways including the central Pi3K/Akt/NF-kB pathway leading to cancer progression and malignancy. Herein, we developed hyaluronic acid-modified poly(dl-lactic-co-glycolic acid)-poly (ethylene glycol) nanoparticles (PLGA-PEG-HA NPs) for targeted delivery of TTQ (thio-tetrazolyl analog of a clinical candidate, IC87114) to CD44 overexpressing cancer cells. The PLGA-PEG co-polymer was synthesized and characterized by NMR and FTIR. The co-polymer based nanoparticles were prepared by solvent evaporation method and hyaluronic acid (HA) was conjugated on to the nanoparticle surface via EDC/NHS chemistry. The PLGA-PEG-HA NPs had a desirable particle size (AFM). In vitro cytotoxicity and cellular uptake studies demonstrated higher cytotoxicity and enhanced intracellular accumulation of PLGA-PEG-HA NPs compared to PLGA-PEG NPs in high CD44 expressing MiaPaca-2 cells compared to MDA-MB-231 and MCF7 cells. At the molecular level, the PLGA-PEG-HA NPs were found to be inducing premature senescence with increase in senescence associated β-galactosidase activity and senescence specific marker p21 expression through modulation of Pi3K/Akt/NF-kB signaling pathway in MiaPaca-2 cells. These findings collectively indicated that HA-modified nanoparticles might serve as a promising nanocarrier for site-specific drug delivery, and can be explored further to increase the therapeutic efficacy of anticancer drugs via targeting to CD44 over-expressing cancer cells. Copyright © 2016. Published by Elsevier B.V.

A viral long terminal repeat expressed in CD4+CD8+ precursors is downregulated in mature peripheral CD4-CD8+ or CD4+CD8- T cells.

OpenAIRE

Paquette, Y; Doyon, L; Laperrière, A; Hanna, Z; Ball, J; Sekaly, R P; Jolicoeur, P

1992-01-01

The long terminal repeat from a thymotropic mouse mammary tumor virus variant, DMBA-LV, was used to drive the expression of two reporter genes, murine c-myc and human CD4, in transgenic mice. Expression was observed specifically in thymic immature cells. Expression of c-myc in these cells induced oligoclonal CD4+ CD8+ T-cell thymomas. Expression of human CD4 was restricted to thymic progenitor CD4- CD8- and CD4+ CD8+ T cells and was shut off in mature CD4+ CD8- and CD4- CD8+ T cells, known to...

Molecular mechanism for the action of the anti-CD44 monoclonal antibody MEM-85

Czech Academy of Sciences Publication Activity Database

Škerlová, Jana; Král, Vlastimil; Kachala, M.; Fábry, Milan; Bumba, Ladislav; Svergun, D.I.; Tosner, Z.; Veverka, V.; Řezáčová, Pavlína

2015-01-01

Roč. 191, č. 2 (2015), s. 214-223 ISSN 1047-8477 R&D Projects: GA ČR(CZ) GA15-11851S EU Projects: European Commission 264257 Institutional support: RVO:68378050 ; RVO:61388971 Keywords : CD44 * Epitope mapping * Monoclonal antibody * MEM-85 * SAXS * NMR Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.570, year: 2015

Proteoglycan from salmon nasal cartridge promotes in vitro wound healing of fibroblast monolayers via the CD44 receptor

International Nuclear Information System (INIS)

Ito, Gen; Kobayashi, Takeshi; Takeda, Yoshie; Sokabe, Masahiro

2015-01-01

Highlights: • Proteoglycan from salmon nasal cartridge (SNC-PG) promoted wound healing in fibroblast monolayers. • SNC-PG stimulated both cell proliferation and cell migration. • Interaction between chondroitin sulfate-units and CD44 is responsible for the effect. - Abstract: Proteoglycans (PGs) are involved in various cellular functions including cell growth, adhesion, and differentiation; however, their physiological roles are not fully understood. In this study, we examined the effect of PG purified from salmon nasal cartilage (SNC-PG) on wound closure using tissue-cultured cell monolayers, an in vitro wound-healing assay. The results indicated that SNC-PG significantly promoted wound closure in NIH/3T3 cell monolayers by stimulating both cell proliferation and cell migration. SNC-PG was effective in concentrations from 0.1 to 10 μg/ml, but showed much less effect at higher concentrations (100–1000 μg/ml). The effect of SNC-PG was abolished by chondroitinase ABC, indicating that chondroitin sulfates (CSs), a major component of glycosaminoglycans (GAGs) in SNC-PG, are crucial for the SNC-PG effect. Furthermore, chondroitin 6-sulfate (C-6-S), a major CS of SNC-PG GAGs, could partially reproduce the SNC-PG effect and partially inhibit the binding of SNC-PG to cells, suggesting that SNC-PG exerts its effect through an interaction between the GAGs in SNC-PG and the cell surface. Neutralization by anti-CD44 antibodies or CD44 knockdown abolished SNC-PG binding to the cells and the SNC-PG effect on wound closure. These results suggest that interactions between CS-rich GAG-chains of SNC-PG and CD44 on the cell surface are responsible for the SNC-PG effect on wound closure

Proteoglycan from salmon nasal cartridge promotes in vitro wound healing of fibroblast monolayers via the CD44 receptor

Energy Technology Data Exchange (ETDEWEB)

Ito, Gen; Kobayashi, Takeshi; Takeda, Yoshie [Department of Physiology, Nagoya University Graduate School of Medicine, Nagoya, Aichi 466-8550 (Japan); Sokabe, Masahiro, E-mail: msokabe@med.nagoya-u.ac.jp [Department of Physiology, Nagoya University Graduate School of Medicine, Nagoya, Aichi 466-8550 (Japan); Mechanobiology Laboratory, Nagoya University Graduate School of Medicine, Nagoya, Aichi 466-8550 (Japan); Mechanobiology Institute Singapore, National University of Singapore, Singapore 117411 (Singapore)

2015-01-16

Highlights: • Proteoglycan from salmon nasal cartridge (SNC-PG) promoted wound healing in fibroblast monolayers. • SNC-PG stimulated both cell proliferation and cell migration. • Interaction between chondroitin sulfate-units and CD44 is responsible for the effect. - Abstract: Proteoglycans (PGs) are involved in various cellular functions including cell growth, adhesion, and differentiation; however, their physiological roles are not fully understood. In this study, we examined the effect of PG purified from salmon nasal cartilage (SNC-PG) on wound closure using tissue-cultured cell monolayers, an in vitro wound-healing assay. The results indicated that SNC-PG significantly promoted wound closure in NIH/3T3 cell monolayers by stimulating both cell proliferation and cell migration. SNC-PG was effective in concentrations from 0.1 to 10 μg/ml, but showed much less effect at higher concentrations (100–1000 μg/ml). The effect of SNC-PG was abolished by chondroitinase ABC, indicating that chondroitin sulfates (CSs), a major component of glycosaminoglycans (GAGs) in SNC-PG, are crucial for the SNC-PG effect. Furthermore, chondroitin 6-sulfate (C-6-S), a major CS of SNC-PG GAGs, could partially reproduce the SNC-PG effect and partially inhibit the binding of SNC-PG to cells, suggesting that SNC-PG exerts its effect through an interaction between the GAGs in SNC-PG and the cell surface. Neutralization by anti-CD44 antibodies or CD44 knockdown abolished SNC-PG binding to the cells and the SNC-PG effect on wound closure. These results suggest that interactions between CS-rich GAG-chains of SNC-PG and CD44 on the cell surface are responsible for the SNC-PG effect on wound closure.

Alternative splicing variants of human Fbx4 disturb cyclin D1 proteolysis in human cancer

International Nuclear Information System (INIS)

Chu, Xiufeng; Zhang, Ting; Wang, Jie; Li, Meng; Zhang, Xiaolei; Tu, Jing; Sun, Shiqin; Chen, Xiangmei; Lu, Fengmin

2014-01-01

Highlights: • The expression of Fbx4 was significantly lower in HCC tissues. • Novel splicing variants of Fbx4 were identified. • These novel variants are much more abundant in human cancer tissues and cells. • The novel Fbx4 isoforms could promote cell proliferation and migration in vitro. • These isoforms showed less capability for cyclin D1 binding and degradation. - Abstract: Fbx4 is a specific substrate recognition component of SCF ubiquitin ligases that catalyzes the ubiquitination and subsequent degradation of cyclin D1 and Trx1. Two isoforms of human Fbx4 protein, the full length Fbx4α and the C-terminal truncated Fbx4β have been identified, but their functions remain elusive. In this study, we demonstrated that the mRNA level of Fbx4 was significantly lower in hepatocellular carcinoma tissues than that in the corresponding non-tumor tissues. More importantly, we identified three novel splicing variants of Fbx4: Fbx4γ (missing 168–245nt of exon1), Fbx4δ (missing exon6) and a N-terminal reading frame shift variant (missing exon2). Using cloning sequencing and RT-PCR, we demonstrated these novel splice variants are much more abundant in human cancer tissues and cell lines than that in normal tissues. When expressed in Sk-Hep1 and NIH3T3 cell lines, Fbx4β, Fbx4γ and Fbx4δ could promote cell proliferation and migration in vitro. Concordantly, these isoforms could disrupt cyclin D1 degradation and therefore increase cyclin D1 expression. Moreover, unlike the full-length isoform Fbx4α that mainly exists in cytoplasm, Fbx4β, Fbx4γ, and Fbx4δ locate in both cytoplasm and nucleus. Since cyclin D1 degradation takes place in cytoplasm, the nuclear distribution of these Fbx4 isoforms may not be involved in the down-regulation of cytoplasmic cyclin D1. These results define the impact of alternative splicing on Fbx4 function, and suggest that the attenuated cyclin D1 degradation by these novel Fbx4 isoforms provides a new insight for aberrant

Alternative splicing variants of human Fbx4 disturb cyclin D1 proteolysis in human cancer

Energy Technology Data Exchange (ETDEWEB)

Chu, Xiufeng; Zhang, Ting; Wang, Jie; Li, Meng; Zhang, Xiaolei; Tu, Jing [Department of Microbiology and Infectious Disease Center, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191 (China); Sun, Shiqin [College of Pharmacy, Harbin Medical University-Daqing, Daqing, Heilongjiang 163319 (China); Chen, Xiangmei, E-mail: xm_chen6176@bjmu.edu.cn [Department of Microbiology and Infectious Disease Center, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191 (China); Lu, Fengmin [Department of Microbiology and Infectious Disease Center, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191 (China)

2014-04-25

Highlights: • The expression of Fbx4 was significantly lower in HCC tissues. • Novel splicing variants of Fbx4 were identified. • These novel variants are much more abundant in human cancer tissues and cells. • The novel Fbx4 isoforms could promote cell proliferation and migration in vitro. • These isoforms showed less capability for cyclin D1 binding and degradation. - Abstract: Fbx4 is a specific substrate recognition component of SCF ubiquitin ligases that catalyzes the ubiquitination and subsequent degradation of cyclin D1 and Trx1. Two isoforms of human Fbx4 protein, the full length Fbx4α and the C-terminal truncated Fbx4β have been identified, but their functions remain elusive. In this study, we demonstrated that the mRNA level of Fbx4 was significantly lower in hepatocellular carcinoma tissues than that in the corresponding non-tumor tissues. More importantly, we identified three novel splicing variants of Fbx4: Fbx4γ (missing 168–245nt of exon1), Fbx4δ (missing exon6) and a N-terminal reading frame shift variant (missing exon2). Using cloning sequencing and RT-PCR, we demonstrated these novel splice variants are much more abundant in human cancer tissues and cell lines than that in normal tissues. When expressed in Sk-Hep1 and NIH3T3 cell lines, Fbx4β, Fbx4γ and Fbx4δ could promote cell proliferation and migration in vitro. Concordantly, these isoforms could disrupt cyclin D1 degradation and therefore increase cyclin D1 expression. Moreover, unlike the full-length isoform Fbx4α that mainly exists in cytoplasm, Fbx4β, Fbx4γ, and Fbx4δ locate in both cytoplasm and nucleus. Since cyclin D1 degradation takes place in cytoplasm, the nuclear distribution of these Fbx4 isoforms may not be involved in the down-regulation of cytoplasmic cyclin D1. These results define the impact of alternative splicing on Fbx4 function, and suggest that the attenuated cyclin D1 degradation by these novel Fbx4 isoforms provides a new insight for aberrant

RON kinase isoforms demonstrate variable cell motility in normal cells.

Science.gov (United States)

Greenbaum, Alissa; Rajput, Ashwani; Wan, Guanghua

2016-09-01

Aberrant RON (Recepteur d'Origine Nantais) tyrosine kinase activation causes the epithelial cell to evade normal growth pathways, resulting in unregulated cell proliferation, increased cell motility and decreased apoptosis. Wildtype (wt) RON has been shown to play a role in metastasis of epithelial malignancies. It presents an important potential therapeutic target for colorectal, breast, gastric and pancreatic cancer. Little is known about functional differences amongst RON isoforms RON155, RON160 and RON165. The purpose of this study was to determine the effect of various RON kinase isoforms on cell motility. Cell lines with stable expression of wtRON were generated by inserting the coding region of RON in pTagRFP (tagged red fluorescence protein plasmid). The expression constructs of RON variants (RON155, RON160 and RON165) were generated by creating a mutagenesis-based wtRON-pTag RFP plasmid and stably transfected into HEK 293 cells. The wound closure scratch assay was used to investigate the effect on cell migratory capacity of wild type RON and its variants. RON transfected cells demonstrated increased cell motility compared to HEK293 control cells. RON165 cell motility was significantly increased compared to RON160 (mean percentage of wound covered 37.37% vs. 32.40%; p = 0.03). RON tyrosine kinase isoforms have variable cell motility. This may reflect a difference in the behavior of malignant epithelial cells and their capacity for metastasis.

Identification of the Molecular Mechanisms Responsible for the Inhibition of Homing of AML Cells Triggered by CD44-Ligation

KAUST Repository

Al-Jifri, Ablah

2011-08-03

Acute Myeloid Leukemia (AML) is a cancerous disease that is defined by the inability to produce functional and mature blood cells, as well as the uncontrolled proliferation due to failure to undergo apoptosis of abnormal cells. The most common therapy for Leukemia, chemotherapy, has proven only to be partially efficient since it does not target the leukemic stem cells (LSCs) that have a high self-renewal and repopulation capacity and result in remission of the disease. Therefore targeting LSCs will provide more efficient therapy. One way to achieve this would be to inhibit their homing capability to the bone marrow. It has recently been shown that CD44, an adhesive molecule, plays a crucial role in cell trafficking and lodgement of both normal and leukemic stem cells. More importantly anti-CD44 monoclonal antibodies, along with its ability to induce differentiation of leukemic blasts, it inhibits specifically the homing capacity of LSCs to their micro-environmental niches. However, these molecular mechanisms that underlie the inhibition of homing have yet to be determined. To address these questions we conducted in vitro adhesion and blot-rolling assays to analyze the adherence and rolling capacity of these LSCs before and after treatment with anti-CD44 monoclonal antibody (mAb). Since glycosyltransferases play a crucial role in post translational carbohydrate decoration on adhesion molecules, we analyzed the expression (using quantitative PCR) of the different glycosyltransferases expressed in LSC\\'s before and after CD44 ligation (mAb treatment). Furthermore, we analyzed differentiation by flow cytometric analysis of treated and non-treated LSC\\'s. We anticipate that our results will set forth new insights into targeted therapies for AML.

Prognostic value of E-cadherin, beta-catenin, CD44v6, and HER2/neu in metastatic cutaneous adenocarcinoma.

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Pozdnyakova, Olga; Hoang, Mai M P; Dresser, Karen A; Mahalingam, Meera

2009-08-01

Our recent experience with a patient developing cutaneous metastases within 3 months of diagnosis of esophageal adenocarcinoma suggests that altered expression of the cellular adhesion molecules, E-cadherin and CD44v6, may have had a role to play in the rapid onset of metastases. To corroborate these findings, we designed a cross-sectional study to investigate the expression of select molecules involved in the metastatic cascade. E-cadherin, beta-catenin, CD44v6, and HER2/neu immunohistochemical stains were performed on archival materials of metastatic adenocarcinoma to the skin from 27 patients and the available corresponding primary tumors in 10 patients. The primary sites included breast (n = 10; 37%), gastrointestinal tract (n = 10; 37%), ovary (n = 1; 4%), thyroid (n = 2; 7%), lung (n = 1; 4%), and unknown primary (n = 3; 11%). Expression of all markers was noted with the most significant increases observed in beta-catenin (26 of 27 cases; 96%), followed by CD44v6 (24 of 27 cases; 89%), E-cadherin (22 of 27 cases; 82%), and HER2/neu (11 of 27 cases; 41%). Contrasting expression of these molecules in the primary versus the metastatic tumors, enhanced expression of CD44v6 was observed in the cutaneous metastases relative to the primary in 6 of 10 (60%) cases. Of interest, 2 of these 6 cases (33%) also showed reduction in E-cadherin--a member of the cadherin family functioning as an invasion suppressor molecule. These findings reinforce the complexities of the metastatic cascade and imply that the variation in adhesive properties of tumor cells is, perhaps, a consequence of the difference in density of the molecules mediating this process.

NMNAT1 variants cause cone and cone-rod dystrophy.

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Nash, Benjamin M; Symes, Richard; Goel, Himanshu; Dinger, Marcel E; Bennetts, Bruce; Grigg, John R; Jamieson, Robyn V

2018-03-01

Cone and cone-rod dystrophies (CD and CRD, respectively) are degenerative retinal diseases that predominantly affect the cone photoreceptors. The underlying disease gene is not known in approximately 75% of autosomal recessive cases. Variants in NMNAT1 cause a severe, early-onset retinal dystrophy called Leber congenital amaurosis (LCA). We report two patients where clinical phenotyping indicated diagnoses of CD and CRD, respectively. NMNAT1 variants were identified, with Case 1 showing an extremely rare homozygous variant c.[271G > A] p.(Glu91Lys) and Case 2 compound heterozygous variants c.[53 A > G];[769G > A] p.(Asn18Ser);(Glu257Lys). The detailed variant analysis, in combination with the observation of an associated macular atrophy phenotype, indicated that these variants were disease-causing. This report demonstrates that the variants in NMNAT1 may cause CD or CRD associated with macular atrophy. Genetic investigations of the patients with CD or CRD should include NMNAT1 in the genes examined.

The interplay of CD150 and CD180 receptor pathways contribute to the pathobiology of chronic lymphocytic leukemia B cells by selective inhibition of Akt and MAPK signaling.

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Inna Gordiienko

Full Text Available Cell surface expression of CD150 and CD180 receptors in chronic lymphocytic leukemia (CLL associates with mutational IGHV status and favourable prognosis. Here we show a direct correlation between cell surface expression and colocalization of these receptors on CLL B cells. In the absence of CD150 and CD180 on the cell surface both receptors were expressed in the cytoplasm. The CD150 receptor was colocalized with markers of the endoplasmic reticulum, the Golgi apparatus and early endosomes. In contrast, CD180 was detected preferentially in early endosomes. Analysis of CD150 isoforms differential expression revealed that regardless of CD150 cell surface expression the mCD150 isoform with two ITSM signaling motifs was a predominant CD150 isoform in CLL B cells. The majority of CLL cases had significantly elevated expression level of the soluble sCD150, moreover CLL B cells secrete this isoform. CD150 or CD180 crosslinking on CLL B cells alone led to activation of Akt, mTORC1, ERK1/2, p38MAPK and JNK1/2 networks. Both CD150 and CD180 target the translation machinery through mTOR independent as well as mTOR dependent pathways. Moreover, both these receptors transmit pro-survival signals via Akt-mediated inhibition of GSK3β and FOXO1/FOXO3a. Unexpectedly, coligation CD150 and CD180 receptors on CLL B cells led to mutual inhibition of the Akt and MAPK pathways. While CD150 and CD180 coligation resulted in reduced phosphorylation of Akt, ERK1/2, c-Jun, RSK, p70S6K, S6RP, and 4E-BP; it led to complete blocking of mTOR and p38MAPK phosphorylation. At the same time coligation of CD150 and CD40 receptors did not result in Akt and MAPK inhibition. This suggests that combination of signals via CD150 and CD180 leads to blocking of pro-survival pathways that may be a restraining factor for neoplastic CLL B cells propagation in more than 50% of CLL cases where these receptors are coexpressed.

CDKL5 variants: Improving our understanding of a rare neurologic disorder.

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Hector, Ralph D; Kalscheuer, Vera M; Hennig, Friederike; Leonard, Helen; Downs, Jenny; Clarke, Angus; Benke, Tim A; Armstrong, Judith; Pineda, Mercedes; Bailey, Mark E S; Cobb, Stuart R

2017-12-01

To provide new insights into the interpretation of genetic variants in a rare neurologic disorder, CDKL5 deficiency, in the contexts of population sequencing data and an updated characterization of the CDKL5 gene. We analyzed all known potentially pathogenic CDKL5 variants by combining data from large-scale population sequencing studies with CDKL5 variants from new and all available clinical cohorts and combined this with computational methods to predict pathogenicity. The study has identified several variants that can be reclassified as benign or likely benign. With the addition of novel CDKL5 variants, we confirm that pathogenic missense variants cluster in the catalytic domain of CDKL5 and reclassify a purported missense variant as having a splicing consequence. We provide further evidence that missense variants in the final 3 exons are likely to be benign and not important to disease pathology. We also describe benign splicing and nonsense variants within these exons, suggesting that isoform hCDKL5_5 is likely to have little or no neurologic significance. We also use the available data to make a preliminary estimate of minimum incidence of CDKL5 deficiency. These findings have implications for genetic diagnosis, providing evidence for the reclassification of specific variants previously thought to result in CDKL5 deficiency. Together, these analyses support the view that the predominant brain isoform in humans (hCDKL5_1) is crucial for normal neurodevelopment and that the catalytic domain is the primary functional domain.

Oestrogen receptor beta isoform expression in sporadic colorectal cancer, familial adenomatous polyposis and progressive stages of colorectal cancer

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Stevanato Filho, Paulo Roberto; Aguiar Júnior, Samuel; Begnami, Maria Dirlei

2017-01-01

BACKGROUND: Among the sex hormones, oestrogen may play a role in colorectal cancer, particularly in conjunction with oestrogen receptor-β (ERβ). The expression of ERβ isoform variants and their correlations with familial adenomatous polyposis (FAP) syndrome and sporadic colorectal carcinomas...... was identified in sporadic polyps and in sporadic colorectal cancer as well as in polyps from FAP syndrome patients compared with normal tissues (p expression in polyps (p ..., no differences were observed when sporadic colorectal carcinomas were compared to normal mucosa tissues. These findings suggest an association of the ERβ isoform variants in individuals affected by germline mutations of the APC gene. Progressively decreased expression of ERβ was found in polyps at early stages...

Comparison of transferrin isoform analysis by capillary electrophoresis and HPLC for screening congenital disorders of glycosylation.

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Dave, Mihika B; Dherai, Alpa J; Udani, Vrajesh P; Hegde, Anaita U; Desai, Neelu A; Ashavaid, Tester F

2018-01-01

Transferrin, a major glycoprotein has different isoforms depending on the number of sialic acid residues present on its oligosaccharide chain. Genetic variants of transferrin as well as the primary (CDG) & secondary glycosylation defects lead to an altered transferrin pattern. Isoform analysis methods are based on charge/mass variations. We aimed to compare the performance of commercially available capillary electrophoresis CDT kit for diagnosing congenital disorders of glycosylation with our in-house optimized HPLC method for transferrin isoform analysis. The isoform pattern of 30 healthy controls & 50 CDG-suspected patients was determined by CE using a Carbohydrate-Deficient Transferrin kit. The results were compared with in-house HPLC-based assay for transferrin isoforms. Transferrin isoform pattern for healthy individuals showed a predominant tetrasialo transferrin fraction followed by pentasialo, trisialo, and disialotransferrin. Two of 50 CDG-suspected patients showed the presence of asialylated isoforms. The results were comparable with isoform pattern obtained by HPLC. The commercial controls showed a <20% CV for each isoform. Bland Altman plot showed the difference plot to be within +1.96 with no systemic bias in the test results by HPLC & CE. The CE method is rapid, reproducible and comparable with HPLC and can be used for screening Glycosylation defects. © 2017 Wiley Periodicals, Inc.

Design and development of hyaluronan-functionalized polybenzofulvene nanoparticles as CD44 receptor mediated drug delivery system

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Licciardi, Mariano; Scialabba, Cinzia; Giammona, Gaetano; Paolino, Marco; Razzano, Vincenzo; Grisci, Giorgio; Giuliani, Germano; Makovec, Francesco; Cappelli, Andrea

2017-06-01

A tri-component polymer brush (TCPB ), composed of a polybenzofulvene copolymer bearing low molecular weight hyaluronic acid (HA) on the surface of its cylindrical brush-like backbone and oligo-PEG fractions, was employed in the preparation of 350 nm nanostructured drug delivery systems capable of delivering the anticancer drug doxorubicin. The obtained drug delivery systems were characterized on the basis of drug loading and release, dimensions and zeta potential, morphology and in vitro cell activity, and uptake on three different human cell lines, namely the bronchial epithelial 16HBE, the breast adenocarcinoma MCF-7, and the colon cancer HCT116 cells. Finally, the ability of doxorubicin-loaded TCPB nanoparticles (DOXO-TCPB) to be internalized into cancer cells by CD44 receptor mediated uptake was assessed by means of uptake studies in HCT cells. These data were supported by anti-CD44-FITC staining assay. The proposed TCPB nanostructured drug delivery systems have many potential applications in nanomedicine, including cancer targeted drug delivery.

Lipid-Based Nanovectors for Targeting of CD44-Overexpressing Tumor Cells

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Silvia Arpicco

2013-01-01

Full Text Available Hyaluronic acid (HA is a naturally occurring glycosaminoglycan that exists in living systems, and it is a major component of the extracellular matrix. The hyaluronic acid receptor CD44 is found at low levels on the surface of epithelial, haematopoietic, and neuronal cells and is overexpressed in many cancer cells particularly in tumour initiating cells. HA has been therefore used as ligand attached to HA-lipid-based nanovectors for the active targeting of small or large active molecules for the treatment of cancer. This paper describes the different approaches employed for the preparation, characterization, and evaluation of these potent delivery systems.

Alternative splicing of the human gene SYBL1 modulates protein domain architecture of longin VAMP7/TI-VAMP, showing both non-SNARE and synaptobrevin-like isoforms

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De Franceschi Nicola

2011-05-01

Full Text Available Abstract Background The control of intracellular vesicle trafficking is an ideal target to weigh the role of alternative splicing in shaping genomes to make cells. Alternative splicing has been reported for several Soluble N-ethylmaleimide-sensitive factor Attachment protein REceptors of the vesicle (v-SNAREs or of the target membrane (t-SNARES, which are crucial to intracellular membrane fusion and protein and lipid traffic in Eukaryotes. However, splicing has not yet been investigated in Longins, i.e. the most widespread v-SNAREs. Longins are essential in Eukaryotes and prototyped by VAMP7, Sec22b and Ykt6, sharing a conserved N-terminal Longin domain which regulates membrane fusion and subcellular targeting. Human VAMP7/TI-VAMP, encoded by gene SYBL1, is involved in multiple cell pathways, including control of neurite outgrowth. Results Alternative splicing of SYBL1 by exon skipping events results in the production of a number of VAMP7 isoforms. In-frame or frameshift coding sequence modifications modulate domain architecture of VAMP7 isoforms, which can lack whole domains or domain fragments and show variant or extra domains. Intriguingly, two main types of VAMP7 isoforms either share the inhibitory Longin domain and lack the fusion-promoting SNARE motif, or vice versa. Expression analysis in different tissues and cell lines, quantitative real time RT-PCR and confocal microscopy analysis of fluorescent protein-tagged isoforms demonstrate that VAMP7 variants have different tissue specificities and subcellular localizations. Moreover, design and use of isoform-specific antibodies provided preliminary evidence for the existence of splice variants at the protein level. Conclusions Previous evidence on VAMP7 suggests inhibitory functions for the Longin domain and fusion/growth promoting activity for the Δ-longin molecule. Thus, non-SNARE isoforms with Longin domain and non-longin SNARE isoforms might have somehow opposite regulatory functions

CEACAM6 gene variants in inflammatory bowel disease.

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Glas, Jürgen; Seiderer, Julia; Fries, Christoph; Tillack, Cornelia; Pfennig, Simone; Weidinger, Maria; Beigel, Florian; Olszak, Torsten; Lass, Ulrich; Göke, Burkhard; Ochsenkühn, Thomas; Wolf, Christiane; Lohse, Peter; Müller-Myhsok, Bertram; Diegelmann, Julia; Czamara, Darina; Brand, Stephan

2011-04-29

The carcinoembryonic antigen-related cell adhesion molecule 6 (CEACAM6) acts as a receptor for adherent-invasive E. coli (AIEC) and its ileal expression is increased in patients with Crohn's disease (CD). Given its contribution to the pathogenesis of CD, we aimed to investigate the role of genetic variants in the CEACAM6 region in patients with inflammatory bowel diseases (IBD). In this study, a total of 2,683 genomic DNA samples (including DNA from 858 CD patients, 475 patients with ulcerative colitis (UC), and 1,350 healthy, unrelated controls) was analyzed for eight CEACAM6 SNPs (rs10415946, rs1805223 = p.Pro42Pro, rs4803507, rs4803508, rs11548735 = p.Gly239Val, rs7246116 = pHis260His, rs2701, rs10416839). In addition, a detailed haplotype analysis and genotype-phenotype analysis were performed. Overall, our genotype analysis did not reveal any significant association of the investigated CEACAM6 SNPs and haplotypes with CD or UC susceptibility, although certain CEACAM6 SNPs modulated CEACAM6 expression in intestinal epithelial cell lines. Despite its function as receptor of AIEC in ileal CD, we found no association of the CEACAM6 SNPs with ileal or ileocolonic CD. Moreover, there was no evidence of epistasis between the analyzed CEACAM6 variants and the main CD-associated NOD2, IL23R and ATG16L1 variants. This study represents the first detailed analysis of CEACAM6 variants in IBD patients. Despite its important role in bacterial attachment in ileal CD, we could not demonstrate a role for CEACAM6 variants in IBD susceptibility or regarding an ileal CD phenotype. Further functional studies are required to analyze if these gene variants modulate ileal bacterial attachment.

CEACAM6 gene variants in inflammatory bowel disease.

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Jürgen Glas

Full Text Available BACKGROUND: The carcinoembryonic antigen-related cell adhesion molecule 6 (CEACAM6 acts as a receptor for adherent-invasive E. coli (AIEC and its ileal expression is increased in patients with Crohn's disease (CD. Given its contribution to the pathogenesis of CD, we aimed to investigate the role of genetic variants in the CEACAM6 region in patients with inflammatory bowel diseases (IBD. METHODOLOGY: In this study, a total of 2,683 genomic DNA samples (including DNA from 858 CD patients, 475 patients with ulcerative colitis (UC, and 1,350 healthy, unrelated controls was analyzed for eight CEACAM6 SNPs (rs10415946, rs1805223 = p.Pro42Pro, rs4803507, rs4803508, rs11548735 = p.Gly239Val, rs7246116 = pHis260His, rs2701, rs10416839. In addition, a detailed haplotype analysis and genotype-phenotype analysis were performed. Overall, our genotype analysis did not reveal any significant association of the investigated CEACAM6 SNPs and haplotypes with CD or UC susceptibility, although certain CEACAM6 SNPs modulated CEACAM6 expression in intestinal epithelial cell lines. Despite its function as receptor of AIEC in ileal CD, we found no association of the CEACAM6 SNPs with ileal or ileocolonic CD. Moreover, there was no evidence of epistasis between the analyzed CEACAM6 variants and the main CD-associated NOD2, IL23R and ATG16L1 variants. CONCLUSIONS: This study represents the first detailed analysis of CEACAM6 variants in IBD patients. Despite its important role in bacterial attachment in ileal CD, we could not demonstrate a role for CEACAM6 variants in IBD susceptibility or regarding an ileal CD phenotype. Further functional studies are required to analyze if these gene variants modulate ileal bacterial attachment.

Spatial distribution of osteopontin, CD44v6 and podoplanin in the lining epithelium of odontogenic keratocyst, and their biological relevance.

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Kechik, Khamisah Awang; Siar, Chong Huat

2018-02-01

The odontogenic keratocyst (OKC) remains the most challenging jaw cyst to treat because of its locally-aggressive behaviour and high recurrence potential. Emerging evidence suggests that osteopontin, its receptors CD44v6 and integrin α v , and podoplanin, have a role in the local invasiveness of this cyst. However the spatial distribution characteristics of these pro-invasive markers in the lining epithelium of OKC, and their association with the clinicopathologic parameters of OKC are largely unexplored. This study sought to address these issues in comparison with dentigerous cysts (DCs) and radicular cysts (RCs) and to evaluate their biological relevance. A sample consisting of 20 OKC cases, 10 DCs and 10 RCs was subjected to immunohistochemical staining for osteopontin, CD44v6 and integrin α v , and podoplanin, and semiquantitative analysis was performed. All factors (except integrin α v ) were detected heterogeneously in the constitutive layers of the lining epithelium in all three cyst types. Key observations were significant upregulation of CD44v6 and podoplanin in OKC compared to DCs and RCs, suggesting that these protein molecules may play crucial roles in promoting local invasiveness in OKC (P<0.05). Osteopontin underexpression and distribution patterns were indistinctive among all three cysts indicating its limited role as pro-invasive factor. Clinical parameters showed no significant correlations with all protein factors investigated. Present findings suggest that an osteopontin low CD44v6 high and podoplanin high immunoprofile most probably represent epithelial signatures of OKC and are markers of local invasiveness in this cyst. Copyright © 2017 Elsevier Inc. All rights reserved.

Impact of Expression of CD44, a Cancer Stem Cell Marker, on the Treatment Outcomes of Intensity Modulated Radiation Therapy in Patients With Oropharyngeal Squamous Cell Carcinoma

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Motegi, Atsushi, E-mail: amotegi@east.ncc.go.jp [Division of Radiation Oncology, National Cancer Center Hospital East, Kashiwa, Chiba (Japan); Fujii, Satoshi [Pathology Division, Research Center for Innovative Oncology, National Cancer Center Hospital East, Kashiwa, Chiba (Japan); Zenda, Sadamoto; Arahira, Satoko [Division of Radiation Oncology, National Cancer Center Hospital East, Kashiwa, Chiba (Japan); Tahara, Makoto [Division of Head and Neck Oncology, National Cancer Center Hospital East, Kashiwa, Chiba (Japan); Hayashi, Ryuichi [Division of Head and Neck Surgery, National Cancer Center Hospital East, Kashiwa, Chiba (Japan); Akimoto, Tetsuo [Division of Radiation Oncology, National Cancer Center Hospital East, Kashiwa, Chiba (Japan)

2016-03-01

Purpose: To investigate the significance of CD44 protein expression on the treatment outcomes of radiation therapy in patients with oropharyngeal squamous cell carcinoma (OPSCC) with or without p16 protein expression in the tumor tissue. Methods and Materials: We reviewed the medical records of 58 OPSCC patients who had undergone radiation therapy and examined the tumor tissue expressions of CD44 and p16 protein by immunohistochemical staining. The correlations between the expressions of these proteins and the patients' treatment outcomes were analyzed. Results: The data of 58 consecutive OPSCC patients who had undergone definitive intensity modulated radiation therapy were analyzed. The male/female ratio was 55:3, and the median age was 64 years. The clinical stage of the disease was stage II in 7 patients, stage III in 5 patients, stage IVA in 35 patients, and stage IVB in 11 patients. Of the patients, 79% received additional induction and/or concurrent chemotherapy. The median follow-up duration was 34 months. The 3-year overall survival, progression-free survival (PFS) and locoregional control (LRC) rates of all the patients, regardless of the results of immunohistochemistry, were 73%, 64% and 76%, respectively. The PFS and LRC rates in the CD44{sup −} patients (86% and 93%, respectively) were significantly higher than those in the CD44{sup +} patients (57% and 70%, respectively). The PFS and LRC rates in the p16{sup +} patients (83% and 90%, respectively) were significantly higher than those in the p16{sup −} patients (45% and 61%, respectively). Patients who were CD44{sup −}/p16{sup +} showed the best LRC rates, and those who were CD44{sup +}/p16{sup −} showed the worst PFS and LRC rates among all the groups. Conclusions: Profiling of CD44 and p16 protein expressions by immunohistochemical staining is useful for predicting the treatment outcomes in patients with OPSCC undergoing definitive intensity modulated radiation therapy.

Second site escape of a T20-dependent HIV-1 variant by a single amino acid change in the CD4 binding region of the envelope glycoprotein

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Berkhout Ben

2006-11-01

Full Text Available Abstract Background We previously described the selection of a T20-dependent human immunodeficiency virus type-1 (HIV-1 variant in a patient on T20 therapy. The fusion inhibitor T20 targets the viral envelope (Env protein by blocking a conformational switch that is critical for viral entry into the host cell. T20-dependent viral entry is the result of 2 mutations in Env (GIA-SKY, creating a protein that undergoes a premature conformational switch, and the presence of T20 prevents this premature switch and rescues viral entry. In the present study, we performed 6 independent evolution experiments with the T20-dependent HIV-1 variant in the absence of T20, with the aim to identify second site compensatory changes, which may provide new mechanistic insights into Env function and the T20-dependence mechanism. Results Escape variants with improved replication capacity appeared within 42 days in 5 evolution cultures. Strikingly, 3 cultures revealed the same single amino acid change in the CD4 binding region of Env (glycine at position 431 substituted for arginine: G431R. This mutation was sufficient to abolish the T20-dependence phenotype and restore viral replication in the absence of T20. The GIA-SKY-G431R escape variant produces an Env protein that exhibits reduced syncytia formation and reduced cell-cell fusion activity. The escape variant was more sensitive to an antibody acting on an early gp41 intermediate, suggesting that the G431R mutation helps preserve a pre-fusion Env conformation, similar to T20 action. The escape variant was also less sensitive to soluble CD4, suggesting a reduced CD4 receptor affinity. Conclusion The forced evolution experiments indicate that the premature conformational switch of the T20-dependent HIV-1 Env variant (GIA-SKY can be corrected by a second site mutation in Env (GIA-SKY-G431R that affects the interaction with the CD4 receptor.

Novel Hyaluronic Acid Conjugates for Dual Nuclear Imaging and Therapy in CD44-Expressing Tumors in Mice In Vivo

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Dubey, Ravindra Dhar; Klippstein, Rebecca; Wang, Julie Tzu-Wen; Hodgins, Naomi; Mei, Kuo-Ching; Sosabowski, Jane; Hider, Robert C.; Abbate, Vincenzo; Gupta, Prem N.; Al-Jamal, Khuloud T.

2017-01-01

Hyaluronic acid, a natural CD44 receptor ligand, has attracted attention in the past years as a macromolecular delivery of anticancer agents to cancer. At the same time, the clinical applications of Gemcitabine (Gem) have been hindered by its short biological half-life, high dose and development of drug resistance. This work reports the synthesis of a hyaluronic acid (HA) conjugate for nuclear imaging, and in vivo Gem delivery to CD44-expressing solid tumors in mice. HA was individually conjugated, via amide coupling, to Gem (HA-Gem), 4'-(aminomethyl)fluorescein hydrochloride (HA-4'-AMF) or tris(hydroxypyridinone) amine (HA-THP) for cancer therapy, in vitro tracking or single photon emission computed tomography/computed tomography (SPECT/CT) imaging, respectively. Gem conjugation to HA was directly confirmed by nuclear magnetic resonance (1H NMR), gel permeation chromatography (GPC) and UV-visible spectrometry, or indirectly by a nucleoside transporter inhibition study. Gem conjugation to HA improved its plasma stability, reduced blood hemolysis and resulted in delayed cytotoxicity in vitro. Uptake inhibition studies in colon CT26 and pancreatic PANC-1 cells, by flow cytometry, revealed that uptake of fluorescent HA conjugate is CD44 receptor and macropinocytosis-dependent. Gamma scintigraphy and SPECT/CT imaging confirmed the relatively prolonged blood circulation profile and uptake in CT26 (1.5 % ID/gm) and PANC-1 (1 % ID/gm) subcutaneous tumors at 24 h after intravenous injection in mice. Four injections of HA-Gem at ~15 mg/kg, over a 28-day period, resulted in significant delay in CT26 tumor growth and prolonged mice survival compared to the free drug. This study reports for the first time dual nuclear imaging and drug delivery (Gem) of HA conjugates to solid tumors in mice. The conjugates show great potential in targeting, imaging and killing of CD44-over expressing cells in vivo. This work is likely to open new avenues for the application of HA

Voltage-Dependent Charge Storage in Cladded Zn0.56Cd0.44Se Quantum Dot MOS Capacitors for Multibit Memory Applications

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Khan, J.; Lingalugari, M.; Al-Amoody, F.; Jain, F.

2013-11-01

As conventional memories approach scaling limitations, new storage methods must be utilized to increase Si yield and produce higher on-chip memory density. Use of II-VI Zn0.56Cd0.44Se quantum dots (QDs) is compatible with epitaxial gate insulators such as ZnS-ZnMgS. Voltage-dependent charging effects in cladded Zn0.56Cd0.44Se QDs are presented in a conventional metal-oxide-semiconductor capacitor structure. Charge storage capabilities in Si and ZnMgS QDs have been reported by various researchers; this work is focused on II-VI material Zn0.56Cd0.44Se QDs nucleated using photoassisted microwave plasma metalorganic chemical vapor deposition. Using capacitance-voltage hysteresis characterization, the multistep charging and discharging capabilities of the QDs at room temperature are presented. Three charging states are presented within a 10 V charging voltage range. These characteristics exemplify discrete charge states in the QD layer, perfect for multibit, QD-functionalized high-density memory applications. Multiple charge states with low operating voltage provide device characteristics that can be used for multibit storage by allowing varying charges to be stored in a QD layer based on the applied "write" voltage.

Selection and characterization of T-cell variants lacking molecules involved in T-cell activation (T3 T-cell receptor, T44, and T11): analysis of the functional relationship among different pathways of activation

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Moretta, A.; Poggi, A.; Olive, D.; Bottino, C.; Fortis, C.; Pantaleo, G.; Moretta, L.

1987-01-01

A clone of the interleukin 2-producing Jurkat leukemia cell line termed JA3 (surface phenotype, T3 + , Ti + , T44 + , T11 + , T40 + ) has been used to induce and select cell variants lacking surface molecules involved in T-cell activation. Following 200 rad of γ-radiation (1 rad = 0.01 Gy), cells were treated with monoclonal antibodies (mAbs) directed to T3, Ti, T44, or T11 antigen and complement. After growth of the residual cells in culture, negative cells were cloned under limiting conditions. Depending on the specificity of the mAb used for the immunoselection, three groups of variants were obtained. (i) The use of mAbs directed to T3 or Ti resulted in cell variants that expressed the T3 - Ti - T44 + Leu1 + T11 + T40 + 4F2 + HLA class I + surface phenotype. (ii) Immunoselection with anti-T44 mAb resulted in 2 variants that shared the T3 - Ti - T44 - Leu1 - T11 - T40 - 4F2 - HLA class I + phenotype. (iii) Cell treatment with anti-T11 mAb resulted in 15 variants characterized by the lack of T11 antigen expression and of all the other T-cell-specific surface antigens. Therefore, it appears that the different sets of JA3 cell variants, like T cells at discrete stages of intrathymic differentiation, may follow a coordinated expression of surface differentiation antigens. Analysis of the functional responsiveness of the three distinct groups of JA3 cell variants to different stimuli showed that all produced interleukin 2 in response to A23187 calcium ionophore plus phorbol 12-myristate 13-acetate

Short-Spindled Cell Haemangioblastoma with CD34 Expression: New Histopathological Variant or Just a Stochastic Cytological Singularity?

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Miguel Fdo. Salazar

2016-01-01

Full Text Available Haemangioblastomas are neoplasms of uncertain histogenesis with cellular and reticular variants advocated in current lore. Herein we describe an intriguing cerebellar specimen with unusual traits including spindle cell morphology and CD34 positivity. A thirty-nine-year old man had an infratentorial tumour discovered incidentally and resected three times. In all the instances, histopathological diagnosis was haemangioblastoma; nonetheless, he had neither physical stigmata nor family history of von Hippel-Lindau disease. By histology, the lesion was composed of areas of conventional stromal cells admixed with territories populated by short-spindled cells packed in lobules, sometimes giving the appearance of gomitoli. Immunoperoxidase-coupled reactions confirmed the expression of inhibin A, neuron-specific enolase (NSE, PS100, and CD57 but also revealed focal immunolabeling for CD34, CD99, and FXIIIa. This case highlights the potential phenotypical diversity that can be found within these neoplasms. Rather than uncertain histogenesis, it may in fact reflect multiple lines of differentiation—histomimesis—prone to adopt unusual morpho- and immunophenotypes in a subset of haemangioblastomas.

Human Renal Normal, Tumoral, and Cancer Stem Cells Express Membrane-Bound Interleukin-15 Isoforms Displaying Different Functions

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Sandy Azzi

2015-06-01

Full Text Available Intrarenal interleukin-15 (IL-15 participates to renal pathophysiology, but the role of its different membrane-bound isoforms remains to be elucidated. In this study, we reassess the biology of membrane-bound IL-15 (mb-IL-15 isoforms by comparing primary cultures of human renal proximal tubular epithelial cells (RPTEC to peritumoral (ptumTEC, tumoral (RCC, and cancer stem cells (CSC/CD105+. RPTEC express a 14 to 16 kDa mb-IL-15, whose existence has been assumed but never formally demonstrated and likely represents the isoform anchored at the cell membrane through the IL-15 receptor α (IL-15Rα chain, because it is sensitive to acidic treatment and is not competent to deliver a reverse signal. By contrast, ptumTEC, RCC, and CSC express a novel N-hyperglycosylated, short-lived transmembrane mb-IL-15 (tmb-IL-15 isoform around 27 kDa, resistant to acidic shock, delivering a reverse signal in response to its soluble receptor (sIL-15Rα. This reverse signal triggers the down-regulation of the tumor suppressor gene E-cadherin in ptumTEC and RCC but not in CSC/CD105+, where it promotes survival. Indeed, through the AKT pathway, tmb-IL-15 protects CSC/CD105+ from non-programmed cell death induced by serum starvation. Finally, both mb-IL-15 and tmb-IL-15 are sensitive to metalloproteases, and the cleaved tmb-IL-15 (25 kDa displays a powerful anti-apoptotic effect on human hematopoietic cells. Overall, our data indicate that both mb-IL-15 and tmb-IL-15 isoforms play a complex role in renal pathophysiology downregulating E-cadherin and favoring cell survival. Moreover, “apparently normal” ptumTEC cells, sharing different properties with RCC, could contribute to organize an enlarged peritumoral “preneoplastic” environment committed to favor tumor progression.

In vivo characterization of the novel CD44v6-targeting Fab fragment AbD15179 for molecular imaging of squamous cell carcinoma: a dual-isotope study

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2014-01-01

Background Patients with squamous cell carcinoma in the head and neck region (HNSCC) offer a diagnostic challenge due to difficulties to detect small tumours and metastases. Imaging methods available are not sufficient, and radio-immunodiagnostics could increase specificity and sensitivity of diagnostics. The objective of this study was to evaluate, for the first time, the in vivo properties of the radiolabelled CD44v6-targeting fragment AbD15179 and to assess its utility as a targeting agent for radio-immunodiagnostics of CD44v6-expressing tumours. Methods The fully human CD44v6-targeting Fab fragment AbD15179 was labelled with 111In or 125I, as models for radionuclides suitable for imaging with SPECT or PET. Species specificity, antigen specificity and internalization properties were first assessed in vitro. In vivo specificity and biodistribution were then evaluated in tumour-bearing mice using a dual-tumour and dual-isotope setup. Results Both species-specific and antigen-specific binding of the conjugates were demonstrated in vitro, with no detectable internalization. The in vivo studies demonstrated specific tumour binding and favourable tumour targeting properties for both conjugates, albeit with higher tumour uptake, slower tumour dissociation, higher tumour-to-blood ratio and higher CD44v6 sensitivity for the 111In-labelled fragment. In contrast, the 125I-Fab demonstrated more favourable tumour-to-organ ratios for liver, spleen and kidneys. Conclusions We conclude that AbD15179 efficiently targets CD44v6-expressing squamous cell carcinoma xenografts, and particularly, the 111In-Fab displayed high and specific tumour uptake. CD44v6 emerges as a suitable target for radio-immunodiagnostics, and a fully human antibody fragment such as AbD15179 can enable further clinical imaging studies. PMID:24598405

Delayed wound healing in aged skin rat models after thermal injury is associated with an increased MMP-9, K6 and CD44 expression.

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Simonetti, Oriana; Oriana, Simonetti; Lucarini, Guendalina; Guendalina, Lucarini; Cirioni, Oscar; Oscar, Cirioni; Zizzi, Antonio; Antonio, Zizzi; Orlando, Fiorenza; Fiorenza, Orlando; Provinciali, Mauro; Mauro, Provinciali; Di Primio, Roberto; Roberto, Di Primio; Giacometti, Andrea; Andrea, Giacometti; Offidani, Annamaria; Annamaria, Offidani

2013-06-01

Age-related differences in wound healing have been documented but little is known about the wound healing mechanism after burns. Our aim was to compare histological features and immunohistochemical expression of matrix metalloproteinase-9 (MMP-9), collagen IV, K6 and CD44 in the burn wound healing process in aged and young rats. Following burns the appearance of the wound bed in aged rats had progressed but slowly, resulting in a delayed healing process compared to the young rats. At 21 days after injury, epithelial K6, MMP-9 and CD44 expression was significantly increased in aged rats with respect to young rats; moreover, in the aged rat group we observed a not fully reconstituted basement membrane. K6, MMP-9 and CD44 expression was significantly increased in wounded skin compared to unwounded skin both in young and aged rats. We hypothesise that delayed burn skin wound healing process in the aged rats may represent an age dependent response to injury where K6, MMP-9 and CD44 play a key role. It is therefore possible to suggest that these factors contribute to the delayed wound healing in aged skin and that modulation could lead to a better and faster recovery of skin damage in elderly. Copyright © 2012 Elsevier Ltd and ISBI. All rights reserved.

RAGE splicing variants in mammals.

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Sterenczak, Katharina Anna; Nolte, Ingo; Murua Escobar, Hugo

2013-01-01

The receptor for advanced glycation end products (RAGE) is a multiligand receptor of environmental stressors which plays key roles in pathophysiological processes, including immune/inflammatory disorders, Alzheimer's disease, diabetic arteriosclerosis, tumorigenesis, and metastasis. Besides the full-length RAGE protein in humans nearly 20 natural occurring RAGE splicing variants were described on mRNA and protein level. These naturally occurring isoforms are characterized by either N-terminally or C-terminally truncations and are discussed as possible regulators of the full-length RAGE receptor either by competitive ligand binding or by displacing the full-length protein in the membrane. Accordingly, expression deregulations of the naturally occurring isoforms were supposed to have significant effect on RAGE-mediated disorders. Thereby the soluble C-truncated RAGE isoforms present in plasma and tissues are the mostly focused isoforms in research and clinics. Deregulations of the circulating levels of soluble RAGE forms were reported in several RAGE-associated pathological disorders including for example atherosclerosis, diabetes, renal failure, Alzheimer's disease, and several cancer types. Regarding other mammalian species, the canine RAGE gene showed high similarities to the corresponding human structures indicating RAGE to be evolutionary highly conserved between both species. Similar to humans the canine RAGE showed a complex and extensive splicing activity leading to a manifold pattern of RAGE isoforms. Due to the similarities seen in several canine and human diseases-including cancer-comparative structural and functional analyses allow the development of RAGE and ligand-specific therapeutic approaches beneficial for human and veterinary medicine.

Glycoprotein CD44 expression in normal, hyperplasic and neoplastic endometrium. An immunohistochemical study including correlations with p53, steroid receptor status and proliferative indices (PCNA, MIB1).

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Zagorianakou, N; Ioachim, E; Mitselou, A; Kitsou, E; Zagorianakou, P; Stefanaki, S; Makrydimas, G; Agnantis, N J

2003-01-01

We have studied by immunohistochemistry the presence and localization of CD44, estrogen and progesterone receptors, p53 and proliferative associated indices (MIB1, PCNA) in archival endometrial tissue, in order to determine their diagnostic and prognostic value as well as the possible correlations between them. We examined 186 samples of endometrial tissue (100 endometrial carcinomas of endometrioid type, 40 cases of hyperplasia and 46 of normal endometrium). Patient records were examined for FIGO stage, grade, and depth of myometrial invasion, histology, and lympho-vascular space invasion. Strong membranous immunostaining (> 10% of neoplastic cells) was observed in 45% of the carcinomas. A statistically significant correlation was found in the expression of protein in stromal cells, when compared with epithelial cells (p failed to show any statistical correlation with tumor grade or with vessel invasion. The expression of the protein was lower in FIGO Stage II compared with Stage I (p = 0.03). A positive relation of CD44 expression with progesterone receptor status (p = 0.02) was detected. CD44 expression was also positively associated with the proliferation associated with the proliferative index MIB1 (p = 0.001). CD44 is closely related to the secretory phase of the normal menstrual cycle and its expression is decreased in hyperplasia (simple or complex with or without atypia) and in cancer cases. These observations suggest that decreased CD44 expression might be functionally involved in the multiple mechanisms of the development and progression of endometrial lesions.

Complete identification of E-selectin ligands on neutrophils reveals distinct functions of PSGL-1, ESL-1, and CD44.

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Hidalgo, Andrés; Peired, Anna J; Wild, Martin; Vestweber, Dietmar; Frenette, Paul S

2007-04-01

The selectins and their ligands are required for leukocyte extravasation during inflammation. Several glycoproteins have been suggested to bind to E-selectin in vitro, but the complete identification of its physiological ligands has remained elusive. Here, we showed that E-selectin ligand-1 (ESL-1), P-selectin glycoprotein ligand-1 (PSGL-1), and CD44 encompassed all endothelial-selectin ligand activity on neutrophils by using gene- and RNA-targeted loss of function. PSGL-1 played a major role in the initial leukocyte capture, whereas ESL-1 was critical for converting initial tethers into steady slow rolling. CD44 controlled rolling velocity and mediated E-selectin-dependent redistribution of PSGL-1 and L-selectin to a major pole on slowly rolling leukocytes through p38 signaling. These results suggest distinct and dynamic contributions of these three glycoproteins in selectin-mediated neutrophil adhesion and signaling.

Contribution of immunocytochemical stainings for galectin-3, CD44, and HBME1 to fine-needle aspiration cytology diagnosis of papillary thyroid carcinoma.

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Das, Dilip K; Al-Waheeb, Salah K M; George, Sara S; Haji, Bahiyah I; Mallik, Mrinmay K

2014-06-01

In cytology practice some papillary thyroid carcinoma (PTC) cases have indeterminate diagnoses and overlapping cytological features with benign lesions. This study was undertaken to find out if immunocytochemistry using Galectin-3, CD-44 and HBME-1 could be of help in such situations. Forty-six cases consisting of 22 malignancy (PTC) cases, 7 suspicious of (S/O) PTC, 1 follicular neoplasm, 5 follicular lesion of undetermined significance (FLUS), and 11 benign (colloid goiter) cases diagnosed by FNA were included in this study. Staining reactions were graded in a sliding scale of -, 1+, 2+, 3+, and 4+. In an assessment of 100 cells, each cell with weak, and moderate to strong positive reaction were assigned a score of 1 and 4, respectively. Staining reaction of ≥+2 and scores >100 were considered positive. Frequency of cases with ≥+2 reaction, and scores >100 for each of Galectin-3, CD-44, and HBME-1 were significantly higher in PTC or combined PTC and S/O PTC cases as compared with FLUS and benign cases taken together (P = 0.01744 to 0.00000). When the cases were compared according to histological malignant and benign diagnoses, the difference was also significant in respect of ≥+2 reaction, and scores >100 for Galectin-3 and CD44 (P = 0.04923 to 0.00947); however, there was no significant difference, when these parameters for HBME1 were compared. Galectin 3, CD 44, and to some extent HBME 1 are useful immunocytochemical parameters with potential to support FNAC diagnosis of PTC, especially in situations with difficult differential diagnoses. Copyright © 2013 Wiley Periodicals, Inc.

Hyaluronic acid–nimesulide conjugates as anticancer drugs against CD44-overexpressing HT-29 colorectal cancer in vitro and in vivo

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Jian YS

2017-03-01

Full Text Available You-Sin Jian,1 Ching-Wen Chen,1 Chih-An Lin,2 Hsiu-Ping Yu,1 Hua-Yang Lin,3 Ming-Yuan Liao,1 Shu-Huan Wu,1 Yan-Fu Lin,1 Ping-Shan Lai1,2,4,5 1Department of Chemistry, 2PhD Program in Tissue Engineering and Regenerative Medicine, National Chung Hsing University, Taichung, 3Preclinical Development Research Department, Holy Stone Healthcare Co., Ltd., Taipei, 4Research Center for Sustainable Energy and Nanotechnology, 5Rong Hsing Research Center for Translational Medicine, National Chung Hsing University, Taichung, Taiwan Abstract: Carrier-mediated drug delivery systems are promising therapeutics for targeted delivery and improved efficacy and safety of potent cytotoxic drugs. Nimesulide is a multifactorial cyclooxygenase 2 nonsteroidal anti-inflammatory drug with analgesic, antipyretic and potent anticancer properties; however, the low solubility of nimesulide limits its applications. Drugs conjugated with hyaluronic acid (HA are innovative carrier-mediated drug delivery systems characterized by CD44-mediated endocytosis of HA and intracellular drug release. In this study, hydrophobic nimesulide was conjugated to HA of two different molecular weights (360 kDa as HA with high molecular weight [HAH] and 43kDa as HA with low molecular weight [HAL] to improve its tumor-targeting ability and hydrophilicity. Our results showed that hydrogenated nimesulide (N-[4-amino-2-phenoxyphenyl]methanesulfonamide was successfully conjugated with both HA types by carbodiimide coupling and the degree of substitution of nimesulide was 1%, which was characterized by 1H nuclear magnetic resonance 400 MHz and total correlation spectroscopy. Both Alexa Fluor® 647 labeled HAH and HAL could selectively accumulate in CD44-overexpressing HT-29 colorectal tumor area in vivo, as observed by in vivo imaging system. In the in vitro cytotoxic test, HA–nimesulide conjugate displayed >46% cell killing ability at a nimesulide concentration of 400 µM in HT-29 cells, whereas

Detection of alternative splice variants at the proteome level in Aspergillus flavus.

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Chang, Kung-Yen; Georgianna, D Ryan; Heber, Steffen; Payne, Gary A; Muddiman, David C

2010-03-05

Identification of proteins from proteolytic peptides or intact proteins plays an essential role in proteomics. Researchers use search engines to match the acquired peptide sequences to the target proteins. However, search engines depend on protein databases to provide candidates for consideration. Alternative splicing (AS), the mechanism where the exon of pre-mRNAs can be spliced and rearranged to generate distinct mRNA and therefore protein variants, enable higher eukaryotic organisms, with only a limited number of genes, to have the requisite complexity and diversity at the proteome level. Multiple alternative isoforms from one gene often share common segments of sequences. However, many protein databases only include a limited number of isoforms to keep minimal redundancy. As a result, the database search might not identify a target protein even with high quality tandem MS data and accurate intact precursor ion mass. We computationally predicted an exhaustive list of putative isoforms of Aspergillus flavus proteins from 20 371 expressed sequence tags to investigate whether an alternative splicing protein database can assign a greater proportion of mass spectrometry data. The newly constructed AS database provided 9807 new alternatively spliced variants in addition to 12 832 previously annotated proteins. The searches of the existing tandem MS spectra data set using the AS database identified 29 new proteins encoded by 26 genes. Nine fungal genes appeared to have multiple protein isoforms. In addition to the discovery of splice variants, AS database also showed potential to improve genome annotation. In summary, the introduction of an alternative splicing database helps identify more proteins and unveils more information about a proteome.

Basigin (CD147), a multifunctional transmembrane glycoprotein with various binding partners.

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Muramatsu, Takashi

2016-05-01

Basigin, also called CD147 or EMMPRIN, is a transmembrane glycoprotein that belongs to the immunoglobulin superfamily. Basigin has isoforms; the common form (basigin or basigin-2) has two immunoglobulin domains, and the extended form (basigin-1) has three. Basigin is the receptor for cyclophilins, S100A9 and platelet glycoprotein VI, whereas basigin-1 serves as the receptor for the rod-derived cone viability factor. Basigin tightly associates with monocarboxylate transporters and is essential for their cell surface translocation and activities. In the same membrane plane, basigin also associates with other proteins including GLUT1, CD44 and CD98. The carbohydrate portion of basigin is recognized by lectins, such as galectin-3 and E-selectin. These molecular recognitions form the basis for the role of basigin in the transport of nutrients, migration of inflammatory leukocytes and induction of matrix metalloproteinases. Basigin is important in vision, spermatogenesis and other physiological phenomena, and plays significant roles in the pathogenesis of numerous diseases, including cancer. Basigin is also the receptor for an invasive protein RH5, which is present in malaria parasites. © The Authors 2015. Published by Oxford University Press on behalf of the Japanese Biochemical Society.

A Loss-of-Function Splice Acceptor Variant in IGF2 Is Protective for Type 2 Diabetes.

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Mercader, Josep M; Liao, Rachel G; Bell, Avery D; Dymek, Zachary; Estrada, Karol; Tukiainen, Taru; Huerta-Chagoya, Alicia; Moreno-Macías, Hortensia; Jablonski, Kathleen A; Hanson, Robert L; Walford, Geoffrey A; Moran, Ignasi; Chen, Ling; Agarwala, Vineeta; Ordoñez-Sánchez, María Luisa; Rodríguez-Guillen, Rosario; Rodríguez-Torres, Maribel; Segura-Kato, Yayoi; García-Ortiz, Humberto; Centeno-Cruz, Federico; Barajas-Olmos, Francisco; Caulkins, Lizz; Puppala, Sobha; Fontanillas, Pierre; Williams, Amy L; Bonàs-Guarch, Sílvia; Hartl, Chris; Ripke, Stephan; Tooley, Katherine; Lane, Jacqueline; Zerrweck, Carlos; Martínez-Hernández, Angélica; Córdova, Emilio J; Mendoza-Caamal, Elvia; Contreras-Cubas, Cecilia; González-Villalpando, María E; Cruz-Bautista, Ivette; Muñoz-Hernández, Liliana; Gómez-Velasco, Donaji; Alvirde, Ulises; Henderson, Brian E; Wilkens, Lynne R; Le Marchand, Loic; Arellano-Campos, Olimpia; Riba, Laura; Harden, Maegan; Gabriel, Stacey; Abboud, Hanna E; Cortes, Maria L; Revilla-Monsalve, Cristina; Islas-Andrade, Sergio; Soberon, Xavier; Curran, Joanne E; Jenkinson, Christopher P; DeFronzo, Ralph A; Lehman, Donna M; Hanis, Craig L; Bell, Graeme I; Boehnke, Michael; Blangero, John; Duggirala, Ravindranath; Saxena, Richa; MacArthur, Daniel; Ferrer, Jorge; McCarroll, Steven A; Torrents, David; Knowler, William C; Baier, Leslie J; Burtt, Noel; González-Villalpando, Clicerio; Haiman, Christopher A; Aguilar-Salinas, Carlos A; Tusié-Luna, Teresa; Flannick, Jason; Jacobs, Suzanne B R; Orozco, Lorena; Altshuler, David; Florez, Jose C

2017-11-01

Type 2 diabetes (T2D) affects more than 415 million people worldwide, and its costs to the health care system continue to rise. To identify common or rare genetic variation with potential therapeutic implications for T2D, we analyzed and replicated genome-wide protein coding variation in a total of 8,227 individuals with T2D and 12,966 individuals without T2D of Latino descent. We identified a novel genetic variant in the IGF2 gene associated with ∼20% reduced risk for T2D. This variant, which has an allele frequency of 17% in the Mexican population but is rare in Europe, prevents splicing between IGF2 exons 1 and 2. We show in vitro and in human liver and adipose tissue that the variant is associated with a specific, allele-dosage-dependent reduction in the expression of IGF2 isoform 2. In individuals who do not carry the protective allele, expression of IGF2 isoform 2 in adipose is positively correlated with both incidence of T2D and increased plasma glycated hemoglobin in individuals without T2D, providing support that the protective effects are mediated by reductions in IGF2 isoform 2. Broad phenotypic examination of carriers of the protective variant revealed no association with other disease states or impaired reproductive health. These findings suggest that reducing IGF2 isoform 2 expression in relevant tissues has potential as a new therapeutic strategy for T2D, even beyond the Latin American population, with no major adverse effects on health or reproduction. © 2017 by the American Diabetes Association.

Syndecan-1/CD147 association is essential for cyclophilin B-induced activation of p44/42 mitogen-activated protein kinases and promotion of cell adhesion and chemotaxis.

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Pakula, Rachel; Melchior, Aurélie; Denys, Agnès; Vanpouille, Christophe; Mazurier, Joël; Allain, Fabrice

2007-05-01

Many of the biological functions attributed to cell surface proteoglycans are dependent on the interaction with extracellular mediators through their heparan sulphate (HS) moieties and the participation of their core proteins in signaling events. A class of recently identified inflammatory mediators is secreted cyclophilins, which are mostly known as cyclosporin A-binding proteins. We previously demonstrated that cyclophilin B (CyPB) triggers chemotaxis and integrin-mediated adhesion of T lymphocytes mainly of the CD4+/CD45RO+ phenotype. These activities are related to interactions with two types of binding sites, CD147 and cell surface HS. Here, we demonstrate that CyPB-mediated adhesion of CD4+/CD45RO+ T cells is related to p44/42 mitogen-activated protein kinase (MAPK) activation by a mechanism involving CD147 and HS proteoglycans (HSPG). Although HSPG core proteins are represented by syndecan-1, -2, -4, CD44v3 and betaglycan in CD4+/CD45RO+ T cells, we found that only syndecan-1 is physically associated with CD147. The intensity of the heterocomplex increased in response to CyPB, suggesting a transient enhancement and/or stabilization in the association of CD147 to syndecan-1. Pretreatment with anti-syndecan-1 antibodies or knockdown of syndecan-1 expression by RNA interference dramatically reduced CyPB-induced p44/p42 MAPK activation and consequent migration and adhesion, supporting the model in which syndecan-1 serves as a binding subunit to form the fully active receptor of CyPB. Altogether, our findings provide a novel example of a soluble mediator in which a member of the syndecan family plays a critical role in efficient interaction with signaling receptors and initiation of cellular responses.

Activation of VCAM-1 and Its Associated Molecule CD44 Leads to Increased Malignant Potential of Breast Cancer Cells

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Pei-Chen Wang

2014-02-01

Full Text Available VCAM-1 (CD106, a transmembrane glycoprotein, was first reported to play an important role in leukocyte adhesion, leukocyte transendothelial migration and cell activation by binding to integrin VLA-1 (α4β1. In the present study, we observed that VCAM-1 expression can be induced in many breast cancer epithelial cells by cytokine stimulation in vitro and its up-regulation directly correlated with advanced clinical breast cancer stage. We found that VCAM-1 over-expression in the NMuMG breast epithelial cells controls the epithelial and mesenchymal transition (EMT program to increase cell motility rates and promote chemoresistance to doxorubicin and cisplatin in vitro. Conversely, in the established MDAMB231 metastatic breast cancer cell line, we confirmed that knockdown of endogenous VCAM-1 expression reduced cell proliferation and inhibited TGFβ1 or IL-6 mediated cell migration, and increased chemosensitivity. Furthermore, we demonstrated that knockdown of endogenous VCAM-1 expression in MDAMB231 cells reduced tumor formation in a SCID xenograft mouse model. Signaling studies showed that VCAM-1 physically associates with CD44 and enhances CD44 and ABCG2 expression. Our findings uncover the possible mechanism of VCAM-1 activation facilitating breast cancer progression, and suggest that targeting VCAM-1 is an attractive strategy for therapeutic intervention.

α6-Integrin alternative splicing: distinct cytoplasmic variants in stem cell fate specification and niche interaction.

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Zhou, Zijing; Qu, Jing; He, Li; Peng, Hong; Chen, Ping; Zhou, Yong

2018-05-02

α6-Integrin subunit (also known as CD49f) is a stemness signature that has been found on the plasma membrane of more than 30 stem cell populations. A growing body of studies have focused on the critical role of α6-containing integrins (α6β1 and α6β4) in the regulation of stem cell properties, lineage-specific differentiation, and niche interaction. α6-Integrin subunit can be alternatively spliced at the post-transcriptional level, giving rise to divergent isoforms which differ in the cytoplasmic and/or extracellular domains. The cytoplasmic domain of integrins is an important functional part of integrin-mediated signals. Structural changes in the cytoplasmic domain of α6 provide an efficient means for the regulation of stem cell responses to biochemical stimuli and/or biophysical cues in the stem cell niche, thus impacting stem cell fate determination. In this review, we summarize the current knowledge on the structural variants of the α6-integrin subunit and spatiotemporal expression of α6 cytoplasmic variants in embryonic and adult stem/progenitor cells. We highlight the roles of α6 cytoplasmic variants in stem cell fate decision and niche interaction, and discuss the potential mechanisms involved. Understanding of the distinct functions of α6 splicing variants in stem cell biology may inform the rational design of novel stem cell-based therapies for a range of human diseases.

BORIS/CTCFL mRNA isoform expression and epigenetic regulation in epithelial ovarian cancer

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Link, Petra A.; Zhang, Wa; Odunsi, Kunle; Karpf, Adam R.

2013-01-01

Cancer germline (CG) genes are normally expressed in germ cells and aberrantly expressed in a variety of cancers; their immunogenicity has led to the widespread development of cancer vaccines targeting these antigens. BORIS/CTCFL is an autosomal CG antigen and promising cancer vaccine target. BORIS is the only known paralog of CTCF, a gene intimately involved in genomic imprinting, chromatin insulation, and nuclear regulation. We have previously shown that BORIS is expressed in epithelial ovarian cancer (EOC) and that its expression coincides with promoter and global DNA hypomethylation. Recently, 23 different BORIS mRNA variants have been described, and have been functionally grouped into six BORIS isoform families (sf1–sf6). In the present study, we have characterized the expression of BORIS isoform families in normal ovary (NO) and EOC, the latter of which were selected to include two groups with widely varying global DNA methylation status. We find selective expression of BORIS isoform families in NO, which becomes altered in EOC, primarily by the activation of BORIS sf1 in EOC. When comparing EOC samples based on methylation status, we find that BORIS sf1 and sf2 isoform families are selectively activated in globally hypomethylated tumors. In contrast, CTCF is downregulated in EOC, and the ratio of BORIS sf1, sf2, and sf6 isoform families as a function of CTCF is elevated in hypomethylated tumors. Finally, the expression of all BORIS isoform families was induced to varying extents by epigenetic modulatory drugs in EOC cell lines, particularly when DNMT and HDAC inhibitors were used in combination. PMID:23390377

Modified Polyadenylation-Based RT-qPCR Increases Selectivity of Amplification of 3′-MicroRNA Isoforms

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Charlotte Nejad

2018-01-01

Full Text Available MicroRNA (miRNA detection by reverse transcription (RT quantitative real-time PCR (RT-qPCR is the most popular method currently used to measure miRNA expression. Although the majority of miRNA families are constituted of several 3′-end length variants (“isomiRs”, little attention has been paid to their differential detection by RT-qPCR. However, recent evidence indicates that 3′-end miRNA isoforms can exhibit 3′-length specific regulatory functions, underlining the need to develop strategies to differentiate 3′-isomiRs by RT-qPCR approaches. We demonstrate here that polyadenylation-based RT-qPCR strategies targeted to 20–21 nt isoforms amplify entire miRNA families, but that primers targeted to >22 nt isoforms were specific to >21 nt isoforms. Based on this observation, we developed a simple method to increase selectivity of polyadenylation-based RT-qPCR assays toward shorter isoforms, and demonstrate its capacity to help distinguish short RNAs from longer ones, using synthetic RNAs and biological samples with altered isomiR stoichiometry. Our approach can be adapted to many polyadenylation-based RT-qPCR technologies already exiting, providing a convenient way to distinguish long and short 3′-isomiRs.

乳腺癌外周血微转移hSBEM mRNA和CD44V6 mRNA的检测%The detection of micrometastases in the peripheral blood of patients with breast cancer for hSBEM mRNA and CD44V6 mRNA

Institute of Scientific and Technical Information of China (English)

无

2008-01-01

Objective:Successful treatment of breast cancer greatly depends on the early detection of its metastasis, therefore a sensitive and specific biomarker for detecting dissemination of the cancer cells will help to achieve this goal. This study was to evaluate the prognostic significance of human small breast epithelial mucin (hSBEM) and CD44V6 in breast cancer. Methods: The expressions of hSBEM mRNA and CD44V6 mRNA were detected with nested reverse transcription polymerase chain reaction (nested RT-PCR) in 67 samples of breast cancer and adjacent normal breast tissue, 16 samples of breast benign lesions tissue, and 67 specimens of peripheral blood from patients with breast cancer, 16 specimens of benign breast lesions, 20 specimens of healthy volunteers, and 25 (each five cases) other carcinomas tissue samples, including those of gastric carcinoma, colorectal carcinoma, esophageal carcinoma, lung carcinoma, and ovary carcinoma, were analyzed for hSBEM mRNA expression by nested RT-PCR. Results: hSBEM mRNA expression was observed in 62/67 (92.54%)of breast cancer, 14/16 (87.50%) of breast benign lesions and 59/67 (88.05%) of normal breast tissue, with no significant differences between them (P＞0.05). None of the samples from other cancer tissues were positive. In peripheral blood the expression of hSBEM mRNA was detected in 34/67 (50.75%) from patients with breast cancer, with significant increasing (P＜ 0.05) in the cases of metastatic disease (stage Ⅳ) and those with lymph node metastasis compared with localized disease (stage Ⅰ, Ⅱ and Ⅲ) and without lymph node metastasis, but its expression was not found in peripheral blood of patients with benign breast lesions or healthy volunteers. Although CD44V6 mRNA was significantly higher in breast cancer than in benign breast lesions tissue and normal breast tissue, its expression in peripheral blood show no significant difference (P＞0.05) in the patients with breast cancer (82.09%), benign breast lesion (75

The depletion of ATM inhibits colon cancer proliferation and migration via B56γ2-mediated Chk1/p53/CD44 cascades.

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Liu, Rui; Tang, Jiajia; Ding, Chaodong; Liang, Weicheng; Zhang, Li; Chen, Tianke; Xiong, Yan; Dai, Xiaowei; Li, Wenfeng; Xu, Yunsheng; Hu, Jin; Lu, Liting; Liao, Wanqin; Lu, Xincheng

2017-04-01

Ataxia-telangiectasia mutated (ATM) protein kinase is a major guardian of genomic stability, and its well-established function in cancer is tumor suppression. Here, we report an oncogenic role of ATM. Using two isogenic sets of human colon cancer cell lines that differed only in their ATM status, we demonstrated that ATM deficiency significantly inhibits cancer cell proliferation, migration, and invasion. The tumor-suppressive function of ATM depletion is not modulated by the compensatory activation of ATR, but it is associated with B56γ2-mediated Chk1/p53/CD44 signaling pathways. Under normal growth conditions, the depletion of ATM prevents B56γ2 ubiquitination and degradation, which activates PP2A-mediated Chk1/p53/p21 signaling pathways, leading to senescence and cell cycle arrest. CD44 was validated as a novel ATM target based on its ability to rescue cell migration and invasion defects in ATM-depleted cells. The activation of p53 induced by ATM depletion suppresses CD44 transcription, thus resulting in epithelial-mesenchymal transition (EMT) and cell migration suppression. Our study suggests that ATM has tumorigenic potential in post-formed colon neoplasia, and it supports ATM as an appealing target for improving cancer therapy. Copyright © 2017 Elsevier B.V. All rights reserved.

TAPAS: tools to assist the targeted protein quantification of human alternative splice variants.

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Yang, Jae-Seong; Sabidó, Eduard; Serrano, Luis; Kiel, Christina

2014-10-15

In proteomes of higher eukaryotes, many alternative splice variants can only be detected by their shared peptides. This makes it highly challenging to use peptide-centric mass spectrometry to distinguish and to quantify protein isoforms resulting from alternative splicing events. We have developed two complementary algorithms based on linear mathematical models to efficiently compute a minimal set of shared and unique peptides needed to quantify a set of isoforms and splice variants. Further, we developed a statistical method to estimate the splice variant abundances based on stable isotope labeled peptide quantities. The algorithms and databases are integrated in a web-based tool, and we have experimentally tested the limits of our quantification method using spiked proteins and cell extracts. The TAPAS server is available at URL http://davinci.crg.es/tapas/. luis.serrano@crg.eu or christina.kiel@crg.eu Supplementary data are available at Bioinformatics online. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Signal transduction by normal isoforms and W mutant variants of the Kit receptor tyrosine kinase.

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Reith, A D; Ellis, C; Lyman, S D; Anderson, D M; Williams, D E; Bernstein, A; Pawson, T

1991-09-01

Germline mutations at the Dominant White Spotting (W) and Steel (Sl) loci have provided conclusive genetic evidence that c-kit mediated signal transduction pathways are essential for normal mouse development. We have analysed the interactions of normal and mutant W/c-kit gene products with cytoplasmic signalling proteins, using transient c-kit expression assays in COS cells. In addition to the previously identified c-kit gene product (Kit+), a second normal Kit isoform (KitA+) containing an in-frame insertion, Gly-Asn-Asn-Lys, within the extracellular domain, was detected in murine mast cell cultures and mid-gestation placenta. Both Kit+ and KitA+ isoforms showed increased autophosphorylation and enhanced association with phosphatidylinositol (PI) 3' kinase and PLC gamma 1, when stimulated with recombinant soluble Steel factor. No association or increase in phosphorylation of GAP and two GAP-associated proteins, p62 and p190, was observed. The two isoforms had distinct activities in the absence of exogenous soluble Steel factor; Kit+, but not KitA+, showed constitutive tyrosine phosphorylation that was accompanied by a low constitutive level of association with PI-3' kinase and PLC gamma 1. Introduction of the point substitutions associated with W37 (Glu582----Lys) or W41 (Val831----Met) mutant alleles into c-kit expression constructs abolished (W37) or reduced (W41) the Steel factor-induced association of the Kit receptor with signalling proteins in a manner proportional to the overall severity of the corresponding W mutant phenotype. These data suggest a diversity of normal Kit signalling pathways and indicate that W mutant phenotypes result from primary defects in the Kit receptor that affect its interaction with cytoplasmic signalling proteins.

Study of association of CD40-CD154 gene polymorphisms with disease susceptibility and cardiovascular risk in Spanish rheumatoid arthritis patients.

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Mercedes García-Bermúdez

Full Text Available Rheumatoid arthritis (RA is a chronic inflammatory disease associated with increased cardiovascular (CV mortality. Since CD40-CD154 binding has direct consequences on inflammation process initiation, we aimed to replicate previous findings related to disease susceptibility in Spanish RA population. Furthermore, as the major complication in RA disease patients is the development of CV events due to accelerated atherosclerosis, and elevated levels of CD40L/CD154 are present in patients with acute myocardial infarction, we assessed the potential association of CD40 and CD154/CD40L gene variants with CV risk in Spanish RA patients.One thousand five hundred and seventy-five patients fulfilling the 1987 ACR classification criteria for RA and 1600 matched controls were genotyped for the CD40 rs1883832, rs4810485 and rs1535045 and CD154 rs3092952 and rs3092920 gene polymorphisms, using predesigned TaqMan single nucleotide polymorphism genotyping assays. Afterwards, we investigated the influence of CD40-CD154 gene variants in the development of CV events. Also, in a subgroup of 273 patients without history of CV events, we assessed the influence of these polymorphisms in the risk of subclinical atherosclerosis determined by carotid ultrasonography.Nominally significant differences in the allele frequencies for the rs1883832 CD40 gene polymorphism between RA patients and controls were found (p=0.038. Although we did not observe a significant association of CD40-CD154 gene variants with the development of CV events, an ANCOVA model adjusted for sex, age at the time of the ultrasonography assessment, follow-up time, traditional CV risk factors and anti-cyclic citrullinated peptide antibodies disclosed a significant association (p=0.0047 between CD40 rs1535045 polymorphism and carotid intima media thickness, a surrogate marker of atherosclerosis.Data from our pilot study indicate a potential association of rs1883832 CD40 gene polymorphism with susceptibility

Seed Dormancy in Arabidopsis Requires Self-Binding Ability of DOG1 Protein and the Presence of Multiple Isoforms Generated by Alternative Splicing.

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Kazumi Nakabayashi

2015-12-01

Full Text Available The Arabidopsis protein DELAY OF GERMINATION 1 (DOG1 is a key regulator of seed dormancy, which is a life history trait that determines the timing of seedling emergence. The amount of DOG1 protein in freshly harvested seeds determines their dormancy level. DOG1 has been identified as a major dormancy QTL and variation in DOG1 transcript levels between accessions contributes to natural variation for seed dormancy. The DOG1 gene is alternatively spliced. Alternative splicing increases the transcriptome and proteome diversity in higher eukaryotes by producing transcripts that encode for proteins with altered or lost function. It can also generate tissue specific transcripts or affect mRNA stability. Here we suggest a different role for alternative splicing of the DOG1 gene. DOG1 produces five transcript variants encoding three protein isoforms. Transgenic dog1 mutant seeds expressing single DOG1 transcript variants from the endogenous DOG1 promoter did not complement because they were non-dormant and lacked DOG1 protein. However, transgenic plants overexpressing single DOG1 variants from the 35S promoter could accumulate protein and showed complementation. Simultaneous expression of two or more DOG1 transcript variants from the endogenous DOG1 promoter also led to increased dormancy levels and accumulation of DOG1 protein. This suggests that single isoforms are functional, but require the presence of additional isoforms to prevent protein degradation. Subsequently, we found that the DOG1 protein can bind to itself and that this binding is required for DOG1 function but not for protein accumulation. Natural variation for DOG1 binding efficiency was observed among Arabidopsis accessions and contributes to variation in seed dormancy.

Two Isoforms of Yersinia pestis Plasminogen Activator Pla: Intraspecies Distribution, Intrinsic Disorder Propensity, and Contribution to Virulence.

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Dentovskaya, Svetlana V; Platonov, Mikhail E; Svetoch, Tat'yana E; Kopylov, Pavel Kh; Kombarova, Tat'yana I; Ivanov, Sergey A; Shaikhutdinova, Rima Z; Kolombet, Lyubov' V; Chauhan, Sadhana; Ablamunits, Vitaly G; Motin, Vladimir L; Uversky, Vladimir N; Anisimov, Andrey P

2016-01-01

It has been shown previously that several endemic Y. pestis isolates with limited virulence contained the I259 isoform of the outer membrane protease Pla, while the epidemic highly virulent strains possessed only the T259 Pla isoform. Our sequence analysis of the pla gene from 118 Y. pestis subsp. microtus strains revealed that the I259 isoform was present exclusively in the endemic strains providing a convictive evidence of more ancestral origin of this isoform. Analysis of the effects of the I259T polymorphism on the intrinsic disorder propensity of Pla revealed that the I259T mutation slightly increases the intrinsic disorder propensity of the C-terminal tail of Pla and makes this protein slightly more prone for disorder-based protein-protein interactions, suggesting that the T259 Pla could be functionally more active than the I259 Pla. This assumption was proven experimentally by assessing the coagulase and fibrinolytic activities of the two Pla isoforms in human plasma, as well as in a direct fluorometric assay with the Pla peptide substrate. The virulence testing of Pla-negative or expressing the I259 and T259 Pla isoforms Y. pestis subsp. microtus and subsp. pestis strains did not reveal any significant difference in LD50 values and dose-dependent survival assays between them by using a subcutaneous route of challenge of mice and guinea pigs or intradermal challenge of mice. However, a significant decrease in time-to-death was observed in animals infected with the epidemic T259 Pla-producing strains as compared to the parent Pla-negative variants. Survival curves of the endemic I259 Pla+ strains fit between them, but significant difference in mean time to death post infection between the Pla-strains and their I259 Pla+ variants could be seen only in the isogenic set of subsp. pestis strains. These findings suggest an essential role for the outer membrane protease Pla evolution in Y. pestis bubonic infection exacerbation that is necessary for intensification

Identification of a variant form of tyrosine phosphatase LYP

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Ho Wanting T

2010-11-01

Full Text Available Abstract Background Protein tyrosine phosphatases (PTPs are important cell signaling regulators with major pathological implications. LYP (also known as PTPN22 is an intracellular enzyme initially found to be predominately expressed in lymphocytes. Importantly, an allelic R620W variant of LYP is strongly associated with multiple autoimmune diseases, including systemic lupus erythematosus, rheumatoid arthritis, type 1 diabetes, and autoimmune thyroid disease. Results In this study, we isolated a novel isoform of LYP designated LYP3. LYP3 differs from LYP1, the known isoform of LYP, in that it lacks a 28 amino acid segment right after the R620W site embedded in a proline-rich protein-protein interaction motif. Genomic sequence analysis revealed that LYP3 resulted from alternative splicing of the LYP gene located on chromosome 1p 13.3-13.1. Reverse transcription PCR analyses of 48 human tissues demonstrated that both LYP1 and LYP3 are predominantly expressed in primary and secondary lymphoid tissues but the relative expression levels of the two isoforms varies in different human tissues and individuals. Conclusions We thus identified a new variant form of LYP and conducted a comprehensive analysis of LYP tissue expressions. Considering the pathogenesis of LYP R620W, we believe that the expression of LYP3 may have an important role in regulating activity and function of LYP and may be implicated in autoimmune diseases.

Disruption of the Putative Vascular Leak Peptide Sequence in the Stabilized Ricin Vaccine Candidate RTA1-33/44-198

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Charles B. Millard

2013-01-01

Full Text Available Vitetta and colleagues identified and characterized a putative vascular leak peptide (VLP consensus sequence in recombinant ricin toxin A-chain (RTA that contributed to dose-limiting human toxicity when RTA was administered intravenously in large quantities during chemotherapy. We disrupted this potentially toxic site within the more stable RTA1-33/44-198 vaccine immunogen and determined the impact of these mutations on protein stability, structure and protective immunogenicity using an experimental intranasal ricin challenge model in BALB/c mice to determine if the mutations were compatible. Single amino acid substitutions at the positions corresponding with RTA D75 (to A, or N and V76 (to I, or M had minor effects on the apparent protein melting temperature of RTA1-33/44-198 but all four variants retained greater apparent stability than the parent RTA. Moreover, each VLP(− variant tested provided protection comparable with that of RTA1-33/44-198 against supralethal intranasal ricin challenge as judged by animal survival and several biomarkers. To understand better how VLP substitutions and mutations near the VLP site impact epitope structure, we introduced a previously described thermal stabilizing disulfide bond (R48C/T77C along with the D75N or V76I substitutions in RTA1-33/44-198. The D75N mutation was compatible with the adjacent stabilizing R48C/T77C disulfide bond and the Tm was unaffected, whereas the V76I mutation was less compatible with the adjacent disulfide bond involving C77. A crystal structure of the RTA1-33/44-198 R48C/T77C/D75N variant showed that the structural integrity of the immunogen was largely conserved and that a stable immunogen could be produced from E. coli. We conclude that it is feasible to disrupt the VLP site in RTA1-33/44-198 with little or no impact on apparent protein stability or protective efficacy in mice and such variants can be stabilized further by introduction of a disulfide bond.

Cyclophilin B induces integrin-mediated cell adhesion by a mechanism involving CD98-dependent activation of protein kinase C-delta and p44/42 mitogen-activated protein kinases.

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Melchior, Aurélie; Denys, Agnès; Deligny, Audrey; Mazurier, Joël; Allain, Fabrice

2008-02-01

Initially identified as a cyclosporin-A binding protein, cyclophilin B (CyPB) is an inflammatory mediator that induces adhesion of T lymphocytes to fibronectin, by a mechanism dependent on CD147 and alpha 4 beta 1 integrins. Recent findings have suggested that another cell membrane protein, CD98, may cooperate with CD147 to regulate beta1 integrin functions. Based on these functional relationships, we examined the contribution of CD98 in the pro-adhesive activity of CyPB, by utilizing the responsive promonocyte cell line THP-1. We demonstrated that cross-linking CD98 with CD98-AHN-18 antibody mimicked the responses induced by CyPB, i.e. homotypic aggregation, integrin-mediated adhesion to fibronectin and activation of p44/42 MAPK. Consistent with previous data, immunoprecipitation confirmed the existence of a heterocomplex wherein CD147, CD98 and beta1 integrins were associated. We then demonstrated that CyPB-induced cell adhesion and p44/42 MAPK activation were dependent on the participation of phosphoinositide 3-kinase and subsequent activation of protein kinase C-delta. Finally, silencing the expression of CD98 by RNA interference potently reduced CyPB-induced cell responses, thus confirming the role of CD98 in the pro-adhesive activity of CyPB. Altogether, our results support a model whereby CyPB induces integrin-mediated adhesion via interaction with a multimolecular unit formed by the association between CD147, CD98 and beta1 integrins.

Amelioration of murine passive immune thrombocytopenia by IVIg and a therapeutic monoclonal CD44 antibody does not require the Myd88 signaling pathway.

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Andrew R Crow

Full Text Available Immune thrombocytopenia (ITP is an autoimmune bleeding disorder characterized by a low platelet count and the production of anti-platelet antibodies. The majority of ITP patients have antibodies to platelet integrin α(IIbβ₃ (GPIIbIIIa which can direct platelet phagocytosis by macrophages. One effective treatment for patients with ITP is intravenous immunoglobulin (IVIg which rapidly reverses thrombocytopenia. The exact mechanism of IVIg action in human patients is unclear, although in mouse models of passive ITP, IVIg can rapidly increase platelet counts in the absence of adaptive immunity. Another antibody therapeutic that can similarly increase platelet counts independent of adaptive immunity are CD44 antibodies. Toll-like receptors (TLRs are pattern recognition receptors which play a central role in helping direct the innate immune system. Dendritic cells, which are notable for their expression of TLRs, have been directly implicated in IVIg function as an initiator cell, while CD44 can associate with TLR2 and TLR4. We therefore questioned whether IVIg, or the therapeutic CD44 antibody KM114, mediate their ameliorative effects in a manner dependent upon normal TLR function. Here, we demonstrate that the TLR4 agonist LPS does not inhibit IVIg or KM114 amelioration of antibody-induced thrombocytopenia, and that these therapeutics do not ameliorate LPS-induced thrombocytopenia. IVIg was able to significantly ameliorate murine ITP in C3H/HeJ mice which have defective TLR4. All known murine TLRs except TLR3 utilize the Myd88 adapter protein to drive TLR signaling. Employing Myd88 deficient mice, we found that both IVIg and KM114 ameliorate murine ITP in Myd88 deficient mice to the same extent as normal mice. Thus both IVIg and anti-CD44 antibody can mediate their ameliorative effects in murine passive ITP independent of the Myd88 signaling pathway. These data help shed light on the mechanism of action of IVIg and KM114 in the amelioration of

Identification of a type 1 diabetes-associated CD4 promoter haplotype with high constitutive activity

DEFF Research Database (Denmark)

Kristiansen, O P; Karlsen, A E; Larsen, Z M

2004-01-01

screened the human CD4 promoter for mutations and identified three frequent single nucleotide polymorphisms (SNPs): CD4-181C/G, CD4-521C/G and CD4-1050T/C. The SNPs are in strong linkage disequilibrium (LD) and association with the CD4-1188(TTTTC)(5-14) alleles, and we observed nine CD4 promoter haplotypes...... promoter activity and (2) the CD4-181G variant encodes higher stimulated promoter activity than the CD4-181C variant. This difference is in part neutralized in the frequently occurring CD4 promoter haplotypes by the more upstream genetic variants. Thus, we report functional impact of a novel CD4-181C/G SNP...

Redundancy of IL-1 Isoform Signaling and Its Implications for Arterial Remodeling.

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Marina Beltrami-Moreira

Full Text Available Mice deficient in IL-1 receptor 1 (hence unresponsive to both IL-1 isoforms α and β have impaired expansive arterial remodeling due to diminished expression of matrix-degrading enzymes, especially MMP-3. Emergence of IL-1 as a target in cardiovascular disease prompted the investigation of the redundancy of IL-1α and IL-1β in the induction of MMP-3 and other matrix-remodeling enzymes in human cells.Human primary vascular smooth muscle cells (VSMCs and carotid endarterectomy specimens were stimulated with equimolar concentrations of IL-1α or IL-1β and analyzed protease expression by immunoblot and ELISA. Either IL-1α or IL-1β increased the expression of pro-MMP-3 in VSMCs, facilitated VSMC migration through Matrigel, and induced MMP-3 production in specimens from atheromatous plaques. VSMCs also secreted MMP-1 and Cathepsin S (CatS upon stimulation with IL-1α or IL-1β. IL-1 isoforms similarly increased MMP-1 and MMP-9 expression in carotid endarterectomy specimens. We examined the expression of MMP-3 and IL-1 isoforms by immunostaining of carotid atheromata, calculated the % positive areas, and tested associations by linear regression. MMP-3 colocalized with IL-1 isoforms in atheromata. MMP-3+ area in plaques positively associated with IL-1α+ (R2 = 0.61, P<0.001 and with IL-1β + areas (R2 = 0.68, P<0.001. MMP-3+ area within atheroma also associated with CD68+ area, but not with α-smooth muscle actin area.Either IL-1α or IL-1β can induce the expression of enzymes implicated in remodeling of the arterial extracellular matrix, and facilitate human VSMC migration in vitro. Human atheromata contain both IL-1 isoforms in association with immunoreactive MMP-3. This redundancy of IL-1 isoforms suggests that selective blocking of one IL-1 isoform should not impair expansive arterial remodeling, a finding with important clinical implications for therapeutic targeting of IL-1 in atherosclerosis.

Characterization of 14-3-3 isoforms expressed in the Echinococcus granulosus pathogenic larval stage.

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Teichmann, Aline; Vargas, Daiani M; Monteiro, Karina M; Meneghetti, Bruna V; Dutra, Cristine S; Paredes, Rodolfo; Galanti, Norbel; Zaha, Arnaldo; Ferreira, Henrique B

2015-04-03

The 14-3-3 protein family of eukaryotic regulators was studied in Echinococcus granulosus, the causative agent of cystic hydatid disease. These proteins mediate important cellular processes in eukaryotes and are expected to play important roles in parasite biology. Six isoforms of E. granulosus 14-3-3 genes and proteins (Eg14-3-3.1-6) were analyzed, and their phylogenetic relationships were established with bona fide 14-3-3 orthologous proteins from eukaryotic species. Eg14-3-3 isoforms with previous evidence of expression (Eg14-3-3.1-4) in E. granulosus pathogenic larval stage (metacestode) were cloned, and recombinant proteins were used for functional studies. These protein isoforms were detected in different components of E. granulosus metacestode, including interface components with the host. The roles that are played by Eg14-3-3 proteins in parasite biology were inferred from the repertoires of interacting proteins with each isoform, as assessed by gel overlay, cross-linking, and affinity chromatography assays. A total of 95 Eg14-3-3 protein ligands were identified by mass spectrometry. Eg14-3-3 isoforms have shared partners (44 proteins), indicating some overlapping functions; however, they also bind exclusive partners (51 proteins), suggesting Eg14-3-3 functional specialization. These ligand repertoires indicate the involvement of Eg14-3-3 proteins in multiple biochemical pathways in the E. granulosus metacestode and note some degree of isoform specialization.

MDR1 siRNA loaded hyaluronic acid-based CD44 targeted nanoparticle systems circumvent paclitaxel resistance in ovarian cancer

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Yang, Xiaoqian; Lyer, Arun K.; Singh, Amit; Choy, Edwin; Hornicek, Francis J.; Amiji, Mansoor M.; Duan, Zhenfeng

2015-02-01

Development of multidrug resistance (MDR) is an almost universal phenomenon in patients with ovarian cancer, and this severely limits the ultimate success of chemotherapy in the clinic. Overexpression of the MDR1 gene and corresponding P-glycoprotein (Pgp) is one of the best known MDR mechanisms. MDR1 siRNA based strategies were proposed to circumvent MDR, however, systemic, safe, and effective targeted delivery is still a major challenge. Cluster of differentiation 44 (CD44) targeted hyaluronic acid (HA) based nanoparticle has been shown to successfully deliver chemotherapy agents or siRNAs into tumor cells. The goal of this study is to evaluate the ability of HA-PEI/HA-PEG to deliver MDR1 siRNA and the efficacy of the combination of HA-PEI/HA-PEG/MDR1 siRNA with paclitaxel to suppress growth of ovarian cancer. We observed that HA-PEI/HA-PEG nanoparticles can efficiently deliver MDR1 siRNA into MDR ovarian cancer cells, resulting in down-regulation of MDR1 and Pgp expression. Administration of HA-PEI/HA-PEG/MDR1 siRNA nanoparticles followed by paclitaxel treatment induced a significant inhibitory effect on the tumor growth, decreased Pgp expression and increased apoptosis in MDR ovarian cancer mice model. Our findings suggest that CD44 targeted HA-PEI/HA-PEG/MDR1 siRNA nanoparticles can serve as a therapeutic tool with great potentials to circumvent MDR in ovarian cancer.

Frataxin mRNA Isoforms in FRDA Patients and Normal Subjects: Effect of Tocotrienol Supplementation

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Provvidenza Maria Abruzzo

2013-01-01

Full Text Available Friedreich’s ataxia (FRDA is caused by deficient expression of the mitochondrial protein frataxin involved in the formation of iron-sulphur complexes and by consequent oxidative stress. We analysed low-dose tocotrienol supplementation effects on the expression of the three splice variant isoforms (FXN-1, FXN-2, and FXN-3 in mononuclear blood cells of FRDA patients and healthy subjects. In FRDA patients, tocotrienol leads to a specific and significant increase of FXN-3 expression while not affecting FXN-1 and FXN-2 expression. Since no structural and functional details were available for FNX-2 and FXN-3, 3D models were built. FXN-1, the canonical isoform, was then docked on the human iron-sulphur complex, and functional interactions were computed; when FXN-1 was replaced by FXN-2 or FNX-3, we found that the interactions were maintained, thus suggesting a possible biological role for both isoforms in human cells. Finally, in order to evaluate whether tocotrienol enhancement of FXN-3 was mediated by an increase in peroxisome proliferator-activated receptor-γ (PPARG, PPARG expression was evaluated. At a low dose of tocotrienol, the increase of FXN-3 expression appeared to be independent of PPARG expression. Our data show that it is possible to modulate the mRNA expression of the minor frataxin isoforms and that they may have a functional role.

Bacterial Production, Characterization and Protein Modeling of a Novel Monofuctional Isoform of FAD Synthase in Humans: An Emergency Protein?

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Piero Leone

2018-01-01

Full Text Available FAD synthase (FADS, EC 2.7.7.2 is the last essential enzyme involved in the pathway of biosynthesis of Flavin cofactors starting from Riboflavin (Rf. Alternative splicing of the human FLAD1 gene generates different isoforms of the enzyme FAD synthase. Besides the well characterized isoform 1 and 2, other FADS isoforms with different catalytic domains have been detected, which are splice variants. We report the characterization of one of these novel isoforms, a 320 amino acid protein, consisting of the sole C-terminal 3′-phosphoadenosine 5′-phosphosulfate (PAPS reductase domain (named FADS6. This isoform has been previously detected in Riboflavin-Responsive (RR-MADD and Non-responsive Multiple Acyl-CoA Dehydrogenase Deficiency (MADD patients with frameshift mutations of FLAD1 gene. To functionally characterize the hFADS6, it has been over-expressed in Escherichia coli and purified with a yield of 25 mg·L−1 of cell culture. The protein has a monomeric form, it binds FAD and is able to catalyze FAD synthesis (kcat about 2.8 min−1, as well as FAD pyrophosphorolysis in a strictly Mg2+-dependent manner. The synthesis of FAD is inhibited by HgCl2. The enzyme lacks the ability to hydrolyze FAD. It behaves similarly to PAPS. Combining threading and ab-initio strategy a 3D structural model for such isoform has been built. The relevance to human physio-pathology of this FADS isoform is discussed.

Enhanced formation and survival of CD4+ CD25hi Foxp3+ T-cells in chronic lymphocytic leukemia

NARCIS (Netherlands)

Jak, Margot; Mous, Rogier; Remmerswaal, Ester B. M.; Spijker, René; Jaspers, Annelieke; Yagüe, Adriana; Eldering, Eric; van Lier, René A. W.; van Oers, Marinus H. J.

2009-01-01

Recently, it has been described that patients with chronic lymphocytic leukemia (CLL) have increased numbers of regulatory T (T(reg)) cells. In the present study, we analysed the mechanism behind T(reg) cells expansion in CLL. Neither analysis of the T-cell receptor repertoire nor CD45 isoform

Promising Noninvasive Cellular Phenotype in Prostate Cancer Cells Knockdown of Matrix Metalloproteinase 9

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Aditi Gupta

2013-01-01

Full Text Available Cell surface interaction of CD44 and MMP9 increases migration and invasion of PC3 cells. We show here that stable knockdown of MMP9 in PC3 cells switches CD44 isoform expression from CD44s to CD44v6 which is more glycosylated. These cells showed highly adhesive morphology with extensive cell spreading which is due to the formation of focal adhesions and well organized actin-stress fibers. MMP9 knockdown blocks invadopodia formation and matrix degradation activity as well. However, CD44 knockdown PC3 cells failed to develop focal adhesions and stress fibers; hence these cells make unstable adhesions. A part of the reason for these changes could be caused by silencing of CD44v6 as well. Immunostaining of prostate tissue microarray sections illustrated significantly lower levels of CD44v6 in adenocarcinoma than normal tissue. Our results suggest that interaction between CD44 and MMP9 is a potential mechanism of invadopodia formation. CD44v6 expression may be essential for the protection of non-invasive cellular phenotype. CD44v6 decrease may be a potential marker for prognosis and therapeutics.

Exogenous and endogenous hyaluronic acid reduces HIV infection of CD4+ T cells

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Li, Peilin; Fujimoto, Katsuya; Bourguingnon, Lilly; Yukl, Steven; Deeks, Steven; Wong, Joseph K

2014-01-01

Preventing mucosal transmission of HIV is critical to halting the HIV epidemic. Novel approaches to preventing mucosal transmission are needed. Hyaluronic acid (HA) is a major extracellular component of mucosa and the primary ligand for the cell surface receptor CD44. CD44 enhances HIV infection of CD4+ T cells, but the role of HA in this process is not clear. To study this, virions were generated with CD44 (HIVCD44) or without CD44 (HIVmock). Exogenous HA reduced HIV infection of unstimulated CD4+ T cells in a CD44-dependent manner. Conversely, hyaluronidase-mediated reduction of endogenous HA on the cell surface enhanced HIV binding to and infection of unstimulated CD4+ T cells. Exogenous HA treatment reduced activation of protein kinase C alpha via CD44 on CD4+ T cells during infection with HIVCD44. These results reveal new roles for HA during the interaction of HIV with CD4+ T cells that may be relevant to mucosal HIV transmission and could be exploitable as a future strategy to prevent HIV infection. PMID:24957217

Association Between Variants of PRDM1 and NDP52 and Crohn's Disease, Based on Exome Sequencing and Functional Studies

DEFF Research Database (Denmark)

Ellinghaus, David; Zhang, Hu; Zeissig, Sebastian

2013-01-01

BACKGROUND & AIMS: Genome-wide association studies (GWAS) have identified 140 Crohn's disease (CD) susceptibility loci. For most loci, the variants that cause disease are not known and the genes affected by these variants have not been identified. We aimed to identify variants that cause CD through...... detailed sequencing, genetic association, expression, and functional studies. METHODS: We sequenced whole exomes of 42 unrelated subjects with CD and 5 healthy subjects (controls) and then filtered single nucleotide variants by incorporating association results from meta-analyses of CD GWAS and in silico...... mutation effect prediction algorithms. We then genotyped 9348 subjects with CD, 2868 subjects with ulcerative colitis, and 14,567 control subjects and associated variants analyzed in functional studies using materials from subjects and controls and in vitro model systems. RESULTS: We identified rare...

A cell surface chondroitin sulfate proteoglycan, immunologically related to CD44, is involved in type I collagen-mediated melanoma cell motility and invasion

DEFF Research Database (Denmark)

Faassen, A E; Schrager, J A; Klein, D J

1992-01-01

The metastatic spread of tumor cells occurs through a complex series of events, one of which involves the adhesion of tumor cells to extracellular matrix (ECM) components. Multiple interactions between cell surface receptors of an adherent tumor cell and the surrounding ECM contribute to cell...... collagen could also be inhibited by removing cell surface chondroitin sulfate with chondroitinase. In contrast, type I collagen-mediated melanoma cell adhesion and spreading were not affected by either beta-D-xyloside or chondroitinase treatments. These results suggest that mouse melanoma CSPG...... was shown to be mediated, at least in part, by chondroitin sulfate. Additionally we have determined that mouse melanoma CSPG is composed of a 110-kD core protein that is recognized by anti-CD44 antibodies on Western blots. Collectively, our data suggests that interactions between a cell surface CD44-related...

Synthesis, crystal structure and luminescent properties of one 3D Cd(II) coordination polymer [Cd(H3BPTC)2(bpy)]n (H4BPTC = 1,1'-biphenyl-2,2',6,6'-tetracarboxylic acid, bpy = 4,4'-bipyridine).

Science.gov (United States)

Mei, Chong-Zhen; Shan, Wen-Wen; Liu, Bing-Tao

2011-10-15

A new 3D metal-organic coordination polymer [Cd(H(3)BPTC)(2)(bpy)](n) (1) (H(4)BPTC = 1,1'-biphenyl-2,2',6,6'-tetracarboxylic acid, bpy =4,4'-bipyridine) has been synthesized and characterized by single X-ray diffraction and IR spectroscopy. The one-dimensional metal-organic chains of the title complex, namely [Cd(H(3)BPTC)(2)](n), are held together through hydrogen bonding and bridging "second" ligand 4,4'-bpy to give a three-dimensional metal-organic network. The thermal stability of complex 1 was studied by thermal gravimetric (TG) and differential thermal analysis (DTA). Compound 1 exhibits photoluminescence with an emission maximum at ca. 380 nm upon excitation at ca. 251 nm. Copyright © 2011 Elsevier B.V. All rights reserved.

Organotypic culture of normal, dysplastic and squamous cell carcinoma-derived oral cell lines reveals loss of spatial regulation of CD44 and p75 NTR in malignancy.

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Dalley, Andrew J; AbdulMajeed, Ahmad A; Upton, Zee; Farah, Camile S

2013-01-01

Oral squamous cell carcinomas (OSCC) often arise from dysplastic lesions. The role of cancer stem cells in tumour initiation is widely accepted, yet the potential existence of pre-cancerous stem cells in dysplastic tissue has received little attention. Cell lines from oral diseases ranging in severity from dysplasia to malignancy provide opportunity to investigate the involvement of stem cells in malignant progression from dysplasia. Stem cells are functionally defined by their ability to generate hierarchical tissue structures in consortium with spatial regulation. Organotypic cultures readily display tissue hierarchy in vitro; hence, in this study, we compared hierarchical expression of stem cell-associated markers in dermis-based organotypic cultures of oral epithelial cells from normal tissue (OKF6-TERT2), mild dysplasia (DOK), severe dysplasia (POE-9n) and OSCC (PE/CA P J15). Expression of CD44, p75(NTR), CD24 and ALDH was studied in monolayers by flow cytometry and in organotypic cultures by immunohistochemistry. Spatial regulation of CD44 and p75(NTR) was evident for organotypic cultures of normal (OKF6-TERT2) and dysplasia (DOK and POE-9n) but was lacking for OSCC (PE/CA PJ15)-derived cells. Spatial regulation of CD24 was not evident. All monolayer cultures exhibited CD44, p75(NTR), CD24 antigens and ALDH activity (ALDEFLUOR(®) assay), with a trend towards loss of population heterogeneity that mirrored disease severity. In monolayer, increased FOXA1 and decreased FOXA2 expression correlated with disease severity, but OCT3/4, Sox2 and NANOG did not. We conclude that dermis-based organotypic cultures give opportunity to investigate the mechanisms that underlie loss of spatial regulation of stem cell markers seen with OSCC-derived cells. © 2012 John Wiley & Sons A/S.

Deep Sequencing Reveals Uncharted Isoform Heterogeneity of the Protein-Coding Transcriptome in Cerebral Ischemia.

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Bhattarai, Sunil; Aly, Ahmed; Garcia, Kristy; Ruiz, Diandra; Pontarelli, Fabrizio; Dharap, Ashutosh

2018-06-03

Gene expression in cerebral ischemia has been a subject of intense investigations for several years. Studies utilizing probe-based high-throughput methodologies such as microarrays have contributed significantly to our existing knowledge but lacked the capacity to dissect the transcriptome in detail. Genome-wide RNA-sequencing (RNA-seq) enables comprehensive examinations of transcriptomes for attributes such as strandedness, alternative splicing, alternative transcription start/stop sites, and sequence composition, thus providing a very detailed account of gene expression. Leveraging this capability, we conducted an in-depth, genome-wide evaluation of the protein-coding transcriptome of the adult mouse cortex after transient focal ischemia at 6, 12, or 24 h of reperfusion using RNA-seq. We identified a total of 1007 transcripts at 6 h, 1878 transcripts at 12 h, and 1618 transcripts at 24 h of reperfusion that were significantly altered as compared to sham controls. With isoform-level resolution, we identified 23 splice variants arising from 23 genes that were novel mRNA isoforms. For a subset of genes, we detected reperfusion time-point-dependent splice isoform switching, indicating an expression and/or functional switch for these genes. Finally, for 286 genes across all three reperfusion time-points, we discovered multiple, distinct, simultaneously expressed and differentially altered isoforms per gene that were generated via alternative transcription start/stop sites. Of these, 165 isoforms derived from 109 genes were novel mRNAs. Together, our data unravel the protein-coding transcriptome of the cerebral cortex at an unprecedented depth to provide several new insights into the flexibility and complexity of stroke-related gene transcription and transcript organization.

CD133(+)/CD44(+)/Oct4(+)/Nestin(+) stem-like cells isolated from Panc-1 cell line may contribute to multi-resistance and metastasis of pancreatic cancer.

Science.gov (United States)

Wang, Dongqing; Zhu, Haitao; Zhu, Ying; Liu, Yanfang; Shen, Huiling; Yin, Ruigen; Zhang, Zhijian; Su, Zhaoliang

2013-05-01

Pancreatic cancer is an aggressive malignant disease. Owing to the lack of early symptoms, accompanied by extensive metastasis and high resistance to chemotherapy, pancreatic adenocarcinoma becomes the fourth leading cause of cancer-related deaths. In this study, we identified a subpopulation of cells isolated from the Panc-1 cell line and named pancreatic cancer stem-like cells. These Panc-1 stem-like cells expressed high levels of CD133/CD44/Oct4/Nestin. Compared to Panc-1 cells, Panc-1 stem-like cells were resistant to gemcitabine and expressed high levels of MDR1; furthermore, Panc-1 stem-like cells have high anti-apoptotic, but weak proliferative potential. These results indicated that Panc-1 stem-like cells, as a novel group, may be a potential major cause of pancreatic cancer multidrug resistance and extensive metastasis. Copyright © 2012 Elsevier GmbH. All rights reserved.

Comparison of DNA aneuploidy, chromosome 1 abnormalities, MYCN amplification and CD44 expression as prognostic factors in neuroblastoma.

Science.gov (United States)

Christiansen, H; Sahin, K; Berthold, F; Hero, B; Terpe, H J; Lampert, F

1995-01-01

A comparison of the prognostic impact of five molecular variables in a large series was made, including tests of their nonrandom association and multivariate analysis. Molecular data were available for 377 patients and MYCN amplification, cytogenetic chromosome 1p deletion, loss of chromosome 1p heterozygosity, DNA ploidy and CD44 expression were investigated. Their interdependence and influence on event-free survival was tested uni- and multivariately using Pearson's chi 2-test, Kaplan-Meier estimates, log rank tests and the Cox's regression model. MYCN amplification was present in 18% (58/322) of cases and predicted poorer prognosis in localised (P < 0.001), metastatic (P = 0.002) and even 4S (P = 0.040) disease. CD44 expression was found in 86% (127/148) of cases, and was a marker for favourable outcome in patients with neuroblastoma stages 1-3 (P = 0.003) and 4 (P = 0.017). Chromosome 1p deletion was cytogenetically detected in 51% (28/55), and indicated reduced event-free survival in localised neuroblastoma (P = 0.020). DNA ploidy and loss of heterozygosity on chromosome 1p were of less prognostic value. Most factors of prognostic significance were associated with each other. By multivariate analysis, MYCN was selected as the only relevant factor. Risk estimation of high discriminating power is, therefore, possible for patients with localised and metastatic neuroblastoma using stage and MYCN.

Expresión fenotípica de las moléculas CD5 y CD6 en la leucemia linfoide crónica B-CD5+ The B-CD5+ chronic lymphoid leukemia related to the phenotype expression

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Bertha Beatriz Socarrás Ferrer

2009-04-01

Full Text Available Las moléculas CD5 y CD6 tienen función coestimuladora y muestran homología en su estructura. Se evaluó la expresión de la molécula CD6 mediante el uso del anticuerpo monoclonal anti-CD6 (T1 en el inmunofenotipaje celular de pacientes con leucemia linfoide crónica By se comparó con la expresión de la molécula CD5.Los resultados demuestranuna homología en la expresión fenotípica de ambas moléculas, CD5 y CD6, lo que asociado con que ambos receptores linfocitarios se encuentran físicamente vinculados, permite sugerir que la molécula CD6 constituye un marcador biológico de interés en la evaluación del pronóstico y la posibilidad de nuevas variantes terapéuticas en esta enfermedad.CD5 and CD6 molecules have a co-stimulant function and show homology in structure. We assessed CD6 molecule expression using anti-CD6 (T1 monoclonal antibody in the cellular immunophenotyping from patients presenting B chronic lymphoid leukemia, and it was compared to CD5 molecule expression. Results show a homology in phenotype expression of both molecules (CD5 and CD6, what associated with the fact that both lymphocyte receptors are physically linked, allow to suggest that CD6 molecule is a interesting biological marker in prognosis assessment, and the possibility of new therapeutic variants in this disease.

CD133 expression is not restricted to stem cells, and both CD133+ and CD133– metastatic colon cancer cells initiate tumors

Science.gov (United States)

Shmelkov, Sergey V.; Butler, Jason M.; Hooper, Andrea T.; Hormigo, Adilia; Kushner, Jared; Milde, Till; St. Clair, Ryan; Baljevic, Muhamed; White, Ian; Jin, David K.; Chadburn, Amy; Murphy, Andrew J.; Valenzuela, David M.; Gale, Nicholas W.; Thurston, Gavin; Yancopoulos, George D.; D’Angelica, Michael; Kemeny, Nancy; Lyden, David; Rafii, Shahin

2008-01-01

Colon cancer stem cells are believed to originate from a rare population of putative CD133+ intestinal stem cells. Recent publications suggest that a small subset of colon cancer cells expresses CD133, and that only these CD133+ cancer cells are capable of tumor initiation. However, the precise contribution of CD133+ tumor-initiating cells in mediating colon cancer metastasis remains unknown. Therefore, to temporally and spatially track the expression of CD133 in adult mice and during tumorigenesis, we generated a knockin lacZ reporter mouse (CD133lacZ/+), in which the expression of lacZ is driven by the endogenous CD133 promoters. Using this model and immunostaining, we discovered that CD133 expression in colon is not restricted to stem cells; on the contrary, CD133 is ubiquitously expressed on differentiated colonic epithelium in both adult mice and humans. Using Il10–/–CD133lacZ mice, in which chronic inflammation in colon leads to adenocarcinomas, we demonstrated that CD133 is expressed on a full gamut of colonic tumor cells, which express epithelial cell adhesion molecule (EpCAM). Similarly, CD133 is widely expressed by human primary colon cancer epithelial cells, whereas the CD133– population is composed mostly of stromal and inflammatory cells. Conversely, CD133 expression does not identify the entire population of epithelial and tumor-initiating cells in human metastatic colon cancer. Indeed, both CD133+ and CD133– metastatic tumor subpopulations formed colonospheres in in vitro cultures and were capable of long-term tumorigenesis in a NOD/SCID serial xenotransplantation model. Moreover, metastatic CD133– cells form more aggressive tumors and express typical phenotypic markers of cancer-initiating cells, including CD44 (CD44+CD24–), whereas the CD133+ fraction is composed of CD44lowCD24+ cells. Collectively, our data suggest that CD133 expression is not restricted to intestinal stem or cancer-initiating cells, and during the metastatic

Molecular basis for Duarte and Los Angeles variant galactosemia

Energy Technology Data Exchange (ETDEWEB)

Langley, S.D.; Lai, K.; Dembure, P.P. [Emory Univ. School of Medicine, Atlanta, GA (United States)] [and others

1997-02-01

Human erythrocytes that are homozygous for the Duarte enzyme variant of galactosemia (D/D) have a characteristic isoform on isoelectric focusing and 50% reduction in galactose-1-phosphate uridyltransferase (GALT) enzyme activity. The Duarte biochemical phenotype has a molecular genotype of N314D/N314D. The characteristic Duarte isoform is also associated with a variant called the {open_quotes}Los Angeles (LA) phenotype,{close_quotes} which has increased GALT enzyme activity. We evaluated GALT enzyme activity and screened the GALT genes of 145 patients with one or more N314D-containing alleles. We found seven with the LA biochemical phenotype, and all had a 1721C{r_arrow}T transition in exon 7 in cis with the N314D missense mutation. The 1721C{r_arrow}T transition is a neutral polymorphism for leucine at amino acid 218 (L218L). In pedigree analyses, this 1721C{r_arrow}T transition segregated with the LA phenotype of increased GALT activity in three different biochemical phenotypes (LA/N, LA/G, and LA/D). To determine the mechanism for increased activity of the LA variant, we compared GALT mRNA, protein abundance, and enzyme thermal stability in lymphoblast cell lines of D and LA phenotypes with comparable genotypes. GALT protein abundance was increased in LA compared to D alleles, but mRNA was similar among all genotypes. We conclude that the codon change N314D in cis with the base-pair transition 1721C{r_arrow}T produces the LA variant of galactosemia and that this nucleotide change increases GALT activity by increasing GALT protein abundance without increasing transcription or decreasing thermal lability. A favorable codon bias for the mutated codon with consequently increased translation rates is postulated as the mechanism. 23 refs., 3 figs., 4 tabs.

Pre-α-pro-GDNF and Pre-β-pro-GDNF Isoforms Are Neuroprotective in the 6-hydroxydopamine Rat Model of Parkinson's Disease

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Anna-Maija Penttinen

2018-06-01

Full Text Available Glial cell line-derived neurotrophic factor (GDNF is one of the most studied neurotrophic factors. GDNF has two splice isoforms, full-length pre-α-pro-GDNF (α-GDNF and pre-β-pro-GDNF (β-GDNF, which has a 26 amino acid deletion in the pro-region. Thus far, studies have focused solely on the α-GDNF isoform, and nothing is known about the in vivo effects of the shorter β-GDNF variant. Here we compare for the first time the effects of overexpressed α-GDNF and β-GDNF in non-lesioned rat striatum and the partial 6-hydroxydopamine lesion model of Parkinson's disease. GDNF isoforms were overexpressed with their native pre-pro-sequences in the striatum using an adeno-associated virus (AAV vector, and the effects on motor performance and dopaminergic phenotype of the nigrostriatal pathway were assessed. In the non-lesioned striatum, both isoforms increased the density of dopamine transporter-positive fibers at 3 weeks after viral vector delivery. Although both isoforms increased the activity of the animals in cylinder assay, only α-GDNF enhanced the use of contralateral paw. Four weeks later, the striatal tyrosine hydroxylase (TH-immunoreactivity was decreased in both α-GDNF and β-GDNF treated animals. In the neuroprotection assay, both GDNF splice isoforms increased the number of TH-immunoreactive cells in the substantia nigra but did not promote behavioral recovery based on amphetamine-induced rotation or cylinder assays. Thus, the shorter GDNF isoform, β-GDNF, and the full-length α-isoform have comparable neuroprotective efficacy on dopamine neurons of the nigrostriatal circuitry.

Vascular wall-resident CD44+ multipotent stem cells give rise to pericytes and smooth muscle cells and contribute to new vessel maturation.

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Diana Klein

Full Text Available Here, we identify CD44(+CD90(+CD73(+CD34(-CD45(- cells within the adult human arterial adventitia with properties of multipotency which were named vascular wall-resident multipotent stem cells (VW-MPSCs. VW-MPSCs exhibit typical mesenchymal stem cell characteristics including cell surface markers in immunostaining and flow cytometric analyses, and differentiation into adipocytes, chondrocytes and osteocytes under culture conditions. Particularly, TGFß1 stimulation up-regulates smooth muscle cell markers in VW-MPSCs. Using fluorescent cell labelling and co-localisation studies we show that VW-MPSCs differentiate to pericytes/smooth muscle cells which cover the wall of newly formed endothelial capillary-like structures in vitro. Co-implantation of EGFP-labelled VW-MPSCs and human umbilical vein endothelial cells into SCID mice subcutaneously via Matrigel results in new vessels formation which were covered by pericyte- or smooth muscle-like cells generated from implanted VW-MPSCs. Our results suggest that VW-MPSCs are of relevance for vascular morphogenesis, repair and self-renewal of vascular wall cells and for local capacity of neovascularization in disease processes.

Satellite Cells CD44 Positive Drive Muscle Regeneration in Osteoarthritis Patients

Science.gov (United States)

Scimeca, Manuel; Bonanno, Elena; Piccirilli, Eleonora; Baldi, Jacopo; Mauriello, Alessandro; Orlandi, Augusto; Tancredi, Virginia; Gasbarra, Elena; Tarantino, Umberto

2015-01-01

Age-related bone diseases, such as osteoarthritis and osteoporosis, are strongly associated with sarcopenia and muscle fiber atrophy. In this study, we analyzed muscle biopsies in order to demonstrate that, in osteoarthritis patients, both osteophytes formation and regenerative properties of muscle stem cells are related to the same factors. In particular, thanks to immunohistochemistry, transmission electron microscopy, and immunogold labeling we investigated the role of BMP-2 in muscle stem cells activity. In patients with osteoarthritis both immunohistochemistry and transmission electron microscopy allowed us to note a higher number of CD44 positive satellite muscle cells forming syncytium. Moreover, the perinuclear and cytoplasmic expression of BMP-2 assessed by in situ molecular characterization of satellite cells syncytia suggest a very strict correlation between BMP-2 expression and muscle regeneration capability. Summing up, the higher BMP-2 expression in osteoarthritic patients could explain the increased bone mineral density as well as decreased muscle atrophy in osteoarthrosic patients. In conclusion, our results suggest that the control of physiological BMP-2 balance between bone and muscle tissues may be considered as a potential pharmacological target in bone-muscle related pathology. PMID:26101529

Satellite Cells CD44 Positive Drive Muscle Regeneration in Osteoarthritis Patients

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Manuel Scimeca

2015-01-01

Full Text Available Age-related bone diseases, such as osteoarthritis and osteoporosis, are strongly associated with sarcopenia and muscle fiber atrophy. In this study, we analyzed muscle biopsies in order to demonstrate that, in osteoarthritis patients, both osteophytes formation and regenerative properties of muscle stem cells are related to the same factors. In particular, thanks to immunohistochemistry, transmission electron microscopy, and immunogold labeling we investigated the role of BMP-2 in muscle stem cells activity. In patients with osteoarthritis both immunohistochemistry and transmission electron microscopy allowed us to note a higher number of CD44 positive satellite muscle cells forming syncytium. Moreover, the perinuclear and cytoplasmic expression of BMP-2 assessed by in situ molecular characterization of satellite cells syncytia suggest a very strict correlation between BMP-2 expression and muscle regeneration capability. Summing up, the higher BMP-2 expression in osteoarthritic patients could explain the increased bone mineral density as well as decreased muscle atrophy in osteoarthrosic patients. In conclusion, our results suggest that the control of physiological BMP-2 balance between bone and muscle tissues may be considered as a potential pharmacological target in bone-muscle related pathology.

Complete identification of E-selectin ligand activity on neutrophils reveals a dynamic interplay and distinct functions of PSGL-1, ESL-1 and CD44

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Wild, Martin; Vestweber, Dietmar; Frenette, Paul S.

2014-01-01

SUMMARY The selectins and their ligands are required for leukocyte extravasation during inflammation. Several glycoproteins have been suggested to bind to E-selectin in vitro but the complete identification of its physiological ligands has remained elusive. Here, we show using gene- and RNA-targeted loss-of-function that E-selectin ligand-1 (ESL-1), PSGL-1 and CD44 encompass all endothelial selectin ligand activity on neutrophils. PSGL-1 plays a major role in the initial leukocyte capture, while ESL-1 is critical to convert initial tethers into steady slow rolling. CD44 controls rolling velocity and mediates E-selectin-dependent redistribution of PSGL-1 and L-selectin to a major pole on slowly rolling leukocytes through p38 signaling. These results suggest distinct and dynamic contributions of these three glycoproteins in selectin-mediated neutrophil adhesion and signaling. PMID:17442598

DIXDC1 Phosphorylation and Control of Dendritic Morphology Are Impaired by Rare Genetic Variants

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Vickie Kwan

2016-11-01

Full Text Available The development of neural connectivity is essential for brain function, and disruption of this process is associated with autism spectrum disorders (ASDs. DIX domain containing 1 (DIXDC1 has previously been implicated in neurodevelopmental disorders, but its role in postnatal brain function remains unknown. Using a knockout mouse model, we determined that DIXDC1 is a regulator of excitatory neuron dendrite development and synapse function in the cortex. We discovered that MARK1, previously linked to ASDs, phosphorylates DIXDC1 to regulate dendrite and spine development through modulation of the cytoskeletal network in an isoform-specific manner. Finally, rare missense variants in DIXDC1 were identified in ASD patient cohorts via genetic sequencing. Interestingly, the variants inhibit DIXDC1 isoform 1 phosphorylation, causing impairment to dendrite and spine growth. These data reveal that DIXDC1 is a regulator of cortical dendrite and synaptic development and provide mechanistic insight into morphological defects associated with neurodevelopmental disorders.

Aberrant Receptor Internalization and Enhanced FRS2-dependent Signaling Contribute to the Transforming Activity of the Fibroblast Growth Factor Receptor 2 IIIb C3 Isoform*

OpenAIRE

Cha, Jiyoung Y.; Maddileti, Savitri; Mitin, Natalia; Harden, T. Kendall; Der, Channing J.

2009-01-01

Alternative splice variants of fibroblast growth factor receptor 2 (FGFR2) IIIb, designated C1, C2, and C3, possess progressive reduction in their cytoplasmic carboxyl termini (822, 788, and 769 residues, respectively), with preferential expression of the C2 and C3 isoforms in human cancers. We determined that the progressive deletion of carboxyl-terminal sequences correlated with increasing transforming potency. The highly transforming C3 variant lacks five tyrosine r...

Macrophage Migration Inhibitory Factor Mediates Proliferative GN via CD74

Science.gov (United States)

Djudjaj, Sonja; Lue, Hongqi; Rong, Song; Papasotiriou, Marios; Klinkhammer, Barbara M.; Zok, Stephanie; Klaener, Ole; Braun, Gerald S.; Lindenmeyer, Maja T.; Cohen, Clemens D.; Bucala, Richard; Tittel, Andre P.; Kurts, Christian; Moeller, Marcus J.; Floege, Juergen; Ostendorf, Tammo

2016-01-01

Pathologic proliferation of mesangial and parietal epithelial cells (PECs) is a hallmark of various glomerulonephritides. Macrophage migration inhibitory factor (MIF) is a pleiotropic cytokine that mediates inflammation by engagement of a receptor complex involving the components CD74, CD44, CXCR2, and CXCR4. The proliferative effects of MIF may involve CD74 together with the coreceptor and PEC activation marker CD44. Herein, we analyzed the effects of local glomerular MIF/CD74/CD44 signaling in proliferative glomerulonephritides. MIF, CD74, and CD44 were upregulated in the glomeruli of patients and mice with proliferative glomerulonephritides. During disease, CD74 and CD44 were expressed de novo in PECs and colocalized in both PECs and mesangial cells. Stress stimuli induced MIF secretion from glomerular cells in vitro and in vivo, in particular from podocytes, and MIF stimulation induced proliferation of PECs and mesangial cells via CD74. In murine crescentic GN, Mif-deficient mice were almost completely protected from glomerular injury, the development of cellular crescents, and the activation and proliferation of PECs and mesangial cells, whereas wild-type mice were not. Bone marrow reconstitution studies showed that deficiency of both nonmyeloid and bone marrow–derived Mif reduced glomerular cell proliferation and injury. In contrast to wild-type mice, Cd74-deficient mice also were protected from glomerular injury and ensuing activation and proliferation of PECs and mesangial cells. Our data suggest a novel molecular mechanism and glomerular cell crosstalk by which local upregulation of MIF and its receptor complex CD74/CD44 mediate glomerular injury and pathologic proliferation in GN. PMID:26453615

Signal transduction by normal isoforms and W mutant variants of the Kit receptor tyrosine kinase.

OpenAIRE

Reith, A D; Ellis, C; Lyman, S D; Anderson, D M; Williams, D E; Bernstein, A; Pawson, T

1991-01-01

Germline mutations at the Dominant White Spotting (W) and Steel (Sl) loci have provided conclusive genetic evidence that c-kit mediated signal transduction pathways are essential for normal mouse development. We have analysed the interactions of normal and mutant W/c-kit gene products with cytoplasmic signalling proteins, using transient c-kit expression assays in COS cells. In addition to the previously identified c-kit gene product (Kit+), a second normal Kit isoform (KitA+) containing an i...

The retinal specific CD147 Ig0 domain: from molecular structure to biological activity

OpenAIRE

Redzic, Jasmina S.; Armstrong, Geoffrey S.; Isern, Nancy. G.; Jones, David N.M.; Kieft, Jeffrey S.; Eisenmesser, Elan Zohar

2011-01-01

CD147 is a type I transmembrane protein that is involved in inflammatory diseases, cancer progression, and multiple human pathogens utilize CD147 for efficient infection. In several cancers, CD147 expression is so high that it is now used as a prognostic marker. The two primary isoforms of CD147 that are related to cancer progression have been identified, differing in their number of immunoglobulin (Ig)-like domains. These include CD147 Ig1-Ig2 that is ubiquitously expressed in most tissues a...

Association Between Variants of PRDM1 and NDP52 and Crohn's Disease, Based on Exome Sequencing and Functional Studies

NARCIS (Netherlands)

Ellinghaus, David; Zhang, Hu; Zeissig, Sebastian; Lipinski, Simone; Till, Andreas; Jiang, Tao; Stade, Björn; Bromberg, Yana; Ellinghaus, Eva; Keller, Andreas; Rivas, Manuel A.; Skieceviciene, Jurgita; Doncheva, Nadezhda T.; Liu, Xiao; Liu, Qing; Jiang, Fuman; Forster, Michael; Mayr, Gabriele; Albrecht, Mario; Häsler, Robert; Boehm, Bernhard O.; Goodall, Jane; Berzuini, Carlo R.; Lee, James; Andersen, Vibeke; Vogel, Ulla; Kupcinskas, Limas; Kayser, Manfred; Krawczak, Michael; Nikolaus, Susanna; Weersma, Rinse K.; Ponsioen, Cyriel Y.; Sans, Miquel; Wijmenga, Cisca; Strachan, David P.; McArdle, Wendy L.; Vermeire, Séverine; Rutgeerts, Paul; Sanderson, Jeremy D.; Mathew, Christopher G.; Vatn, Morten H.; Wang, Jun; Nöthen, Markus M.; Duerr, Richard H.; Büning, Carsten; Brand, Stephan; Glas, Jürgen; Winkelmann, Juliane; Illig, Thomas; Latiano, Anna; Annese, Vito; Halfvarson, Jonas; D'Amato, Mauro; Daly, Mark J.; Nothnagel, Michael; Karlsen, Tom H.; Subramani, Suresh; Rosenstiel, Philip; Schreiber, Stefan; Parkes, Miles; Franke, Andre

2013-01-01

Genome-wide association studies (GWAS) have identified 140 Crohn's disease (CD) susceptibility loci. For most loci, the variants that cause disease are not known and the genes affected by these variants have not been identified. We aimed to identify variants that cause CD through detailed

A novel MCPH1 isoform complements the defective chromosome condensation of human MCPH1-deficient cells.

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Ioannis Gavvovidis

Full Text Available Biallelic mutations in MCPH1 cause primary microcephaly (MCPH with the cellular phenotype of defective chromosome condensation. MCPH1 encodes a multifunctional protein that notably is involved in brain development, regulation of chromosome condensation, and DNA damage response. In the present studies, we detected that MCPH1 encodes several distinct transcripts, including two major forms: full-length MCPH1 (MCPH1-FL and a second transcript lacking the six 3' exons (MCPH1Δe9-14. Both variants show comparable tissue-specific expression patterns, demonstrate nuclear localization that is mediated independently via separate NLS motifs, and are more abundant in certain fetal than adult organs. In addition, the expression of either isoform complements the chromosome condensation defect found in genetically MCPH1-deficient or MCPH1 siRNA-depleted cells, demonstrating a redundancy of both MCPH1 isoforms for the regulation of chromosome condensation. Strikingly however, both transcripts are regulated antagonistically during cell-cycle progression and there are functional differences between the isoforms with regard to the DNA damage response; MCPH1-FL localizes to phosphorylated H2AX repair foci following ionizing irradiation, while MCPH1Δe9-14 was evenly distributed in the nucleus. In summary, our results demonstrate here that MCPH1 encodes different isoforms that are differentially regulated at the transcript level and have different functions at the protein level.

Differential Expression Profile of ZFX Variants Discriminates Breast Cancer Subtypes

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Pourkeramati, Fatemeh; Asadi, Malek Hossein; Shakeri, Shahryar; Farsinejad, Alireza

2018-05-13

ZFX is a transcriptional regulator in embryonic stem cells that plays an important role in pluripotency and self-renewal. ZFX is widely expressed in pluripotent stem cells and is down-regulated during differentiation of embryonic stem cells. ZFX has five different variants that encode three different protein isoforms. While several reports have determined the overexpression of ZFX in a variety of somatic cancers, the expression of ZFX-spliced variants in cancer cells is not well-understood. We investigated the expression of ZFX variants in a series of breast cancer tissues and cell lines using quantitative PCR. The expression of ZFX variant 1/3 was higher in tumor tissue compared to marginal tissue. In contrast, the ZFX variant 5 was down-regulated in tumor tissues. While the ZFX variant 1/3 and ZFX variant 5 expression significantly increased in low-grade tumors, ZFX variant 4 was strongly expressed in high-grade tumors and demonstrating lymphatic invasion. In addition, our result revealed a significant association between the HER2 status and the expression of ZFX-spliced variants. Our data suggest that the expression of ZFX-spliced transcripts varies between different types of breast cancer and may contribute to their tumorigenesis process. Hence, ZFX-spliced transcripts could be considered as novel tumor markers with a probable value in diagnosis, prognosis, and therapy of breast cancer.

Heterologous expression of a rice metallothionein isoform (OsMTI-1b in Saccharomyces cerevisiae enhances cadmium, hydrogen peroxide and ethanol tolerance

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Zahra Ansarypour

Full Text Available Abstract Metallothioneins are a superfamily of low-molecular-weight, cysteine (Cys-rich proteins that are believed to play important roles in protection against metal toxicity and oxidative stress. The main purpose of this study was to investigate the effect of heterologous expression of a rice metallothionein isoform (OsMTI-1b on the tolerance of Saccharomyces cerevisiae to Cd2+, H2O2 and ethanol stress. The gene encoding OsMTI-1b was cloned into p426GPD as a yeast expression vector. The new construct was transformed to competent cells of S. cerevisiae. After verification of heterologous expression of OsMTI-1b, the new strain and control were grown under stress conditions. In comparison to control strain, the transformed S. cerevisiae cells expressing OsMTI-1b showed more tolerance to Cd2+ and accumulated more Cd2+ ions when they were grown in the medium containing CdCl2. In addition, the heterologous expression of GST-OsMTI-1b conferred H2O2 and ethanol tolerance to S. cerevisiae cells. The results indicate that heterologous expression of plant MT isoforms can enhance the tolerance of S. cerevisiae to multiple stresses.

Structural diversity and evolution of the N-terminal isoform-specific region of ecdysone receptor-A and -B1 isoforms in insects

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Kubo Takeo

2010-02-01

Full Text Available Abstract Background The ecdysone receptor (EcR regulates various cellular responses to ecdysteroids during insect development. Insects have multiple EcR isoforms with different N-terminal A/B domains that contain the isoform-specific activation function (AF-1 region. Although distinct physiologic functions of the EcR isoforms have been characterized in higher holometabolous insects, they remain unclear in basal direct-developing insects, in which only A isoform has been identified. To examine the structural basis of the EcR isoform-specific AF-1 regions, we performed a comprehensive structural comparison of the isoform-specific region of the EcR-A and -B1 isoforms in insects. Results The EcR isoforms were newly identified in 51 species of insects and non-insect arthropods, including direct-developing ametabolous and hemimetabolous insects. The comprehensive structural comparison revealed that the isoform-specific region of each EcR isoform contained evolutionally conserved microdomain structures and insect subgroup-specific structural modifications. The A isoform-specific region generally contained four conserved microdomains, including the SUMOylation motif and the nuclear localization signal, whereas the B1 isoform-specific region contained three conserved microdomains, including an acidic activator domain-like motif. In addition, the EcR-B1 isoform of holometabolous insects had a novel microdomain at the N-terminal end. Conclusions Given that the nuclear receptor AF-1 is involved in cofactor recruitment and transcriptional regulation, the microdomain structures identified in the isoform-specific A/B domains might function as signature motifs and/or as targets for cofactor proteins that play essential roles in the EcR isoform-specific AF-1 regions. Moreover, the novel microdomain in the isoform-specific region of the holometabolous insect EcR-B1 isoform suggests that the holometabolous insect EcR-B1 acquired additional transcriptional

First Trimester Pregnancy Loss and the Expression of alternatively spliced NKp30 isoforms in Maternal Blood and Placental Tissue

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Avishai eShemesh

2015-06-01

Full Text Available In this study, we aimed to investigate whether first trimester pregnancy loss is associated with differences in expression of NKp30 splice variants (isoforms in maternal peripheral blood or placental tissue. We conducted a prospective case-control study; a total of 33 women undergoing dilation and curettage due to first trimester pregnancy loss were further subdivided into groups with sporadic or recurrent pregnancy loss. The control group was comprised of women undergoing elective termination of pregnancy. The qPCR approach was employed to assess the relative expression of NKp30 isoforms as well as the total expression of NKp30 and NKp46 receptors between the selected groups. Results show that in both PBMC and placental tissue, NKp46 and NKp30 expression was mildly elevated in the pregnancy loss groups compared with the elective group. In particular, NKp46 elevation was significant. Moreover, expression analysis of NKp30 isoforms manifested a different profile between PBMC and the placenta. NKp30-a and NKp30-b isoforms in the placental tissue, but not in PBMC, showed a significant increase in the pregnancy loss groups compared with the elective group. Placental expression of NKp30 activating isoforms -a and -b in the pregnancy loss groups was negatively correlated with PLGF expression. In contrast, placental expression of these isoforms in the elective group was positively correlated with TNFα, IL-10 and VEGF-A expression. The altered expression of NKp30 activating isoforms in placental tissue from patients with pregnancy loss compared to the elective group and the different correlations with cytokine expression point to the involvement of NKp30-mediated function in pregnancy loss.

Promoter- and cell-specific epigenetic regulation of CD44, Cyclin D2, GLIPR1 and PTEN by Methyl-CpG binding proteins and histone modifications

International Nuclear Information System (INIS)

Müller, Imke; Wischnewski, Frank; Pantel, Klaus; Schwarzenbach, Heidi

2010-01-01

The aim of the current study was to analyze the involvement of methyl-CpG binding proteins (MBDs) and histone modifications on the regulation of CD44, Cyclin D2, GLIPR1 and PTEN in different cellular contexts such as the prostate cancer cells DU145 and LNCaP, and the breast cancer cells MCF-7. Since global chromatin changes have been shown to occur in tumours and regions of tumour-associated genes are affected by epigenetic modifications, these may constitute important regulatory mechanisms for the pathogenesis of malignant transformation. In DU145, LNCaP and MCF-7 cells mRNA expression levels of CD44, Cyclin D2, GLIPR1 and PTEN were determined by quantitative RT-PCR at the basal status as well as after treatment with demethylating agent 5-aza-2'-deoxycytidine and/or histone deacetylase inhibitor Trichostatin A. Furthermore, genomic DNA was bisulfite-converted and sequenced. Chromatin immunoprecipitation was performed with the stimulated and unstimulated cells using antibodies for MBD1, MBD2 and MeCP2 as well as 17 different histone antibodies. Comparison of the different promoters showed that MeCP2 and MBD2a repressed promoter-specifically Cyclin D2 in all cell lines, whereas in MCF-7 cells MeCP2 repressed cell-specifically all methylated promoters. Chromatin immunoprecipitation showed that all methylated promoters associated with at least one MBD. Treatment of the cells by the demethylating agent 5-aza-2'-deoxycytidine (5-aza-CdR) caused dissociation of the MBDs from the promoters. Only MBD1v1 bound and repressed methylation-independently all promoters. Real-time amplification of DNA immunoprecipitated by 17 different antibodies showed a preferential enrichment for methylated lysine of histone H3 (H3K4me1, H3K4me2 and H3K4me3) at the particular promoters. Notably, the silent promoters were associated with unmodified histones which were acetylated following treatment by 5-aza-CdR. This study is one of the first to reveal the histone code and MBD profile

Association Between Variants of PRDM1 and NDP52 and Crohn's Disease, Based on Exome Sequencing and Functional Studies

NARCIS (Netherlands)

Ellinghaus, David; Zhang, Hu; Zeissig, Sebastian; Lipinski, Simone; Till, Andreas; Jiang, Tao; Stade, Bjoern; Bromberg, Yana; Ellinghaus, Eva; Keller, Andreas; Rivas, Manuel A.; Skieceviciene, Jurgita; Doncheva, Nadezhda T.; Liu, Xiao; Liu, Qing; Jiang, Fuman; Forster, Michael; Mayr, Gabriele; Albrecht, Mario; Haesler, Robert; Boehm, Bernhard O.; Goodall, Jane; Berzuini, Carlo R.; Lee, James; Andersen, Vibeke; Vogel, Ulla; Kupcinskas, Limas; Kayser, Manfred; Krawczak, Michael; Nikolaus, Susanna; Weersma, Rinse K.; Ponsioen, Cyriel Y.; Sans, Miquel; Wijmenga, Cisca; Strachan, David P.; McAardle, Wendy L.; Vermeire, Severine; Rutgeerts, Paul; Sanderson, Jeremy D.; Mathew, Christopher G.; Vatn, Morten H.; Wang, Jun; Noethen, Markus M.; Duerr, Richard H.; Buening, Carsten; Brand, Stephan; Glas, Juergen; Winkelmann, Juliane; Illig, Thomas; Latiano, Anna; Annese, Vito; Halfvarson, Jonas; D'Amato, Mauro; Daly, Mark J.; Nothnagel, Michael; Karlsen, Tom H.; Subramani, Suresh; Rosenstiel, Philip; Schreiber, Stefan; Parkes, Miles; Franke, Andre

BACKGROUND & AIMS: Genome-wide association studies (GWAS) have identified 140 Crohn's disease (CD) susceptibility loci. For most loci, the variants that cause disease are not known and the genes affected by these variants have not been identified. We aimed to identify variants that cause CD through

Allele-Selective Transcriptome Recruitment to Polysomes Primed for Translation: Protein-Coding and Noncoding RNAs, and RNA Isoforms.

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Roshan Mascarenhas

Full Text Available mRNA translation into proteins is highly regulated, but the role of mRNA isoforms, noncoding RNAs (ncRNAs, and genetic variants remains poorly understood. mRNA levels on polysomes have been shown to correlate well with expressed protein levels, pointing to polysomal loading as a critical factor. To study regulation and genetic factors of protein translation we measured levels and allelic ratios of mRNAs and ncRNAs (including microRNAs in lymphoblast cell lines (LCL and in polysomal fractions. We first used targeted assays to measure polysomal loading of mRNA alleles, confirming reported genetic effects on translation of OPRM1 and NAT1, and detecting no effect of rs1045642 (3435C>T in ABCB1 (MDR1 on polysomal loading while supporting previous results showing increased mRNA turnover of the 3435T allele. Use of high-throughput sequencing of complete transcript profiles (RNA-Seq in three LCLs revealed significant differences in polysomal loading of individual RNA classes and isoforms. Correlated polysomal distribution between protein-coding and non-coding RNAs suggests interactions between them. Allele-selective polysome recruitment revealed strong genetic influence for multiple RNAs, attributable either to differential expression of RNA isoforms or to differential loading onto polysomes, the latter defining a direct genetic effect on translation. Genes identified by different allelic RNA ratios between cytosol and polysomes were enriched with published expression quantitative trait loci (eQTLs affecting RNA functions, and associations with clinical phenotypes. Polysomal RNA-Seq combined with allelic ratio analysis provides a powerful approach to study polysomal RNA recruitment and regulatory variants affecting protein translation.

Functional variants of the dopamine receptor D2 gene modulate prefronto-striatal phenotypes in schizophrenia.

Science.gov (United States)

Bertolino, Alessandro; Fazio, Leonardo; Caforio, Grazia; Blasi, Giuseppe; Rampino, Antonio; Romano, Raffaella; Di Giorgio, Annabella; Taurisano, Paolo; Papp, Audrey; Pinsonneault, Julia; Wang, Danxin; Nardini, Marcello; Popolizio, Teresa; Sadee, Wolfgang

2009-02-01

Dopamine D2 receptor signalling is strongly implicated in the aetiology of schizophrenia. We have recently characterized the function of three DRD2 SNPs: rs12364283 in the promoter affecting total D2 mRNA expression; rs2283265 and rs1076560, respectively in introns 5 and 6, shifting mRNA splicing to two functionally distinct isoforms, the short form of D2 (D2S) and the long form (D2L). These two isoforms differentially contribute to dopamine signalling in prefrontal cortex and in striatum. We performed a case-control study to determine association of these variants and of their main haplotypes with several schizophrenia-related phenotypes. We demonstrate that the minor allele in the intronic variants is associated with reduced expression of %D2S of total mRNA in post-mortem prefrontal cortex, and with impaired working memory behavioural performance, both in patients and controls. However, the fMRI results show opposite effects in patients compared with controls: enhanced engagement of prefronto-striatal pathways in controls and reduced activity in patients. Moreover, the promoter variant is also associated with working memory activity in prefrontal cortex and striatum of patients, and less robustly with negative symptoms scores. Main haplotypes formed by the three DRD2 variants showed significant associations with these phenotypes consistent with those of the individual SNPs. Our results indicate that the three functional DRD2 variants modulate schizophrenia phenotypes possibly by modifying D2S/D2L ratios in the context of different total D2 density.

4,4′-Bipyridine-aided synthesis and characterization of Zn(II) and Cd(II) 2-sulfoterephthalate complexes

International Nuclear Information System (INIS)

Xiao, Shan-Shan; Li, Xin-Xin; Zheng, Xiang-Jun; Jia, Tian-Jing; Jin, Lin-Pei

2013-01-01

Six d 10 complexes, [Zn 1.5 (stp)(bpy) 0.5 (H 2 O) 2 ]·0.5H 2 O (1), Cd 1.5 (stp)(bpy) 0.5 (H 2 O) 2 (2), [Cd 1.5 (stp)(bpy)(H 2 O)]·H 2 O (3), [Zn 0.5 (bpy) 0.5 (H 2 O) 2 ][Zn(stp)(bpy)(H 2 O)]·0.5H 2 O (4), Cd 3 (stp) 2 (bpy) 3 (H 2 O) 3 (5), Hbpy·[Zn 0.5 (bpy)(H 2 O) 2 ][Zn 0.5 (stp)(H 2 O)]·H 2 O (6) based on 2-sulfoterephthalate (stp 3− ) and 4,4′-bipyridine (bpy) have been synthesized under hydro/solvo-thermal conditions and structurally characterized. Complex 1 exhibits a three-fold interpenetrated 3D porous architecture. Complexes 2 and 3 possess helices with different chirality arranging alternately. 4 and 6 are addition compounds, which compose of complex cation and complex anion. Complex 5 features a 3D layer-pillar framework in which a (4, 4) grid layer is constructed by stp 3− ligands and Cd(II) ions, and the layers are further connected by bpy pillars. The solid-state luminescent properties of the coordination polymers have also been investigated. - Graphical abstract: Display Omitted - Highlights: • Complexes 1–3 possess helices with different chirality arranging alternately. • The structural diversity can be attributed to various coordination modes of ligands. • The formation of helical structure is related to the adjacent carboxyl and sulfonate groups. • Bpy exhibits three roles: bridge, hydrogen bonding acceptor, and template

Promoter- and cell-specific epigenetic regulation of CD44, Cyclin D2, GLIPR1 and PTEN by Methyl-CpG binding proteins and histone modifications

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Schwarzenbach Heidi

2010-06-01

Full Text Available Abstract Background The aim of the current study was to analyze the involvement of methyl-CpG binding proteins (MBDs and histone modifications on the regulation of CD44, Cyclin D2, GLIPR1 and PTEN in different cellular contexts such as the prostate cancer cells DU145 and LNCaP, and the breast cancer cells MCF-7. Since global chromatin changes have been shown to occur in tumours and regions of tumour-associated genes are affected by epigenetic modifications, these may constitute important regulatory mechanisms for the pathogenesis of malignant transformation. Methods In DU145, LNCaP and MCF-7 cells mRNA expression levels of CD44, Cyclin D2, GLIPR1 and PTEN were determined by quantitative RT-PCR at the basal status as well as after treatment with demethylating agent 5-aza-2'-deoxycytidine and/or histone deacetylase inhibitor Trichostatin A. Furthermore, genomic DNA was bisulfite-converted and sequenced. Chromatin immunoprecipitation was performed with the stimulated and unstimulated cells using antibodies for MBD1, MBD2 and MeCP2 as well as 17 different histone antibodies. Results Comparison of the different promoters showed that MeCP2 and MBD2a repressed promoter-specifically Cyclin D2 in all cell lines, whereas in MCF-7 cells MeCP2 repressed cell-specifically all methylated promoters. Chromatin immunoprecipitation showed that all methylated promoters associated with at least one MBD. Treatment of the cells by the demethylating agent 5-aza-2'-deoxycytidine (5-aza-CdR caused dissociation of the MBDs from the promoters. Only MBD1v1 bound and repressed methylation-independently all promoters. Real-time amplification of DNA immunoprecipitated by 17 different antibodies showed a preferential enrichment for methylated lysine of histone H3 (H3K4me1, H3K4me2 and H3K4me3 at the particular promoters. Notably, the silent promoters were associated with unmodified histones which were acetylated following treatment by 5-aza-CdR. Conclusions This study is one

The prognostic value of Her4 receptor isoform expression in triple-negative and Her2 positive breast cancer patients

International Nuclear Information System (INIS)

Machleidt, Anna; Buchholz, Stefan; Diermeier-Daucher, Simone; Zeman, Florian; Ortmann, Olaf; Brockhoff, Gero

2013-01-01

Not only four but rather seven different human epidermal growth factor receptor related (Her) receptor tyrosine kinases (RTKs) have been described to be expressed in a variety of normal and neoplastic tissues: Her1, Her2, Her3, and additionally four Her4 isoforms have been identified. A differential expression of Her4 isoforms does not, however, play any role in either the molecular diagnostics or treatment decision for breast cancer patients. The prognostic and predictive impact of Her4 expression in breast cancer is basically unclear. We quantified the Her4 variants JM-a/CYT1, JM-a/CYT2, JM-b/CYT1, and JM-b/CYT2 by isoform-specific polymerase chain reaction (qPCR) in (i) triple-negative, (ii) Her2 positive breast cancer tissues and (iii) in benign breast tissues. In all three tissue collectives we never found the JM-b/CYT1 or the JM-b/CYT2 isoform expressed. In contrast, the two JM-a/CYT1 and JM-a/CYT2 isoforms were always simultaneously expressed but at different ratios. We identified a positive prognostic impact on overall survival (OS) in triple-negative and event-free survival (EFS) in Her2 positive patients. This finding is independent of the absolute JM-a/CYT1 to JM-a/CYT2 expression ratio. In Her2 positive patients, Her4 expression only has a favorable effect in estrogen-receptor (ER)-positive but not in ER-negative individuals. In summary, JM-a/CYT1 and JM-a/CYT2 but not JM-b isoforms of the Her4 receptor are simultaneously expressed in both triple-negative and Her2 positive breast cancer tissues. Although different expression ratios of the two JM-a isoforms did not reveal any additional information, Her4 expression basically indicates a prolonged EFS and OFS. An extended expression analysis that takes all Her receptor homologs, including the Her4 isoforms, into account might render more precisely the molecular diagnostics required for the development of optimized targeted therapies

A single molecule assay to probe monovalent and multivalent bonds between hyaluronan and its key leukocyte receptor CD44 under force

Science.gov (United States)

Bano, Fouzia; Banerji, Suneale; Howarth, Mark; Jackson, David G.; Richter, Ralf P.

2016-09-01

Glycosaminoglycans (GAGs), a category of linear, anionic polysaccharides, are ubiquitous in the extracellular space, and important extrinsic regulators of cell function. Despite the recognized significance of mechanical stimuli in cellular communication, however, only few single molecule methods are currently available to study how monovalent and multivalent GAG·protein bonds respond to directed mechanical forces. Here, we have devised such a method, by combining purpose-designed surfaces that afford immobilization of GAGs and receptors at controlled nanoscale organizations with single molecule force spectroscopy (SMFS). We apply the method to study the interaction of the GAG polymer hyaluronan (HA) with CD44, its receptor in vascular endothelium. Individual bonds between HA and CD44 are remarkably resistant to rupture under force in comparison to their low binding affinity. Multiple bonds along a single HA chain rupture sequentially and independently under load. We also demonstrate how strong non-covalent bonds, which are versatile for controlled protein and GAG immobilization, can be effectively used as molecular anchors in SMFS. We thus establish a versatile method for analyzing the nanomechanics of GAG·protein interactions at the level of single GAG chains, which provides new molecular-level insight into the role of mechanical forces in the assembly and function of GAG-rich extracellular matrices.

[Effect of Biejiajian Pills on Wnt signal pathway molecules β-catenin and GSK-3β and the target genes CD44v6 and VEGF in hepatocellular carcinoma cells].

Science.gov (United States)

Sun, Haitao; He, Songqi; Wen, Bin; Jia, Wenyan; Fan, Eryan; Zheng, Yan

2014-10-01

To investigate the effect of Biejiajian Pills on the expressions of the signal molecules and target genes of Wnt signal pathway in HepG2 cells and explore the mechanisms by which Biejiajian pills suppress the invasiveness of hepatocellular carcinoma. HepG2 cells were cultured for 48 h in the presence of serum collected from rats fed with Biejiajian Pills. The expressions of β-catenin, GSK-3β and P-GSK-3β in the cultured cells were assessed by Western blotting and the expressions of CD44v6 and VEGF were detected using immunohistochemistry. HepG2 cells cultured with the serum of rats fed with Biejiajian Pills showed lowered expressions of β-catenin protein both in the cytoplasm and the nuclei with also inhibition of phosphorylation of GSK-3β and reduced expression of CD44v6 and VEGF. Biejiajian Pills can significantly reduce the expression of β-catenin by decreasing the phosphorylation of GSK-3β and blocking the Wnt/β-catenin signaling pathway to cause down-regulation of the target genes CD44v6 and VEGF, which may be one of the molecular mechanisms by which Biejiajian Pills suppress the proliferation and invasiveness of hepatocellular carcinoma.

Not just a marker: CD34 on human hematopoietic stem/progenitor cells dominates vascular selectin binding along with CD44

KAUST Repository

Abu Samra, Dina Bashir Kamil; Aleisa, Fajr A; Al-Amoodi, Asma S.; Jalal Ahmed, Heba M.; Chin, Chee Jia; AbuElela, Ayman; Bergam, Ptissam; Sougrat, Rachid; Merzaban, Jasmeen

2017-01-01

CD34 is routinely used to identify and isolate human hematopoietic stem/progenitor cells (HSPCs) for use clinically in bone marrow transplantation, but its function on these cells remains elusive. Glycoprotein ligands on HSPCs help guide their migration to specialized microvascular beds in the bone marrow that express vascular selectins (E- and P-selectin). Here, we show that HSPC-enriched fractions from human hematopoietic tissue expressing CD34 (CD34pos) bound selectins, whereas those lacking CD34 (CD34neg) did not. An unbiased proteomics screen identified potential glycoprotein ligands on CD34pos cells revealing CD34 itself as a major vascular selectin ligand. Biochemical and CD34 knockdown analyses highlight a key role for CD34 in the first prerequisite step of cell migration, suggesting that it is not just a marker on these cells. Our results also entice future potential strategies to investigate the glycoforms of CD34 that discriminate normal HSPCs from leukemic cells and to manipulate CD34neg HSPC-enriched bone marrow or cord blood populations as a source of stem cells for clinical use.

Not just a marker: CD34 on human hematopoietic stem/progenitor cells dominates vascular selectin binding along with CD44

KAUST Repository

Abu Samra, Dina Bashir Kamil

2017-12-27

CD34 is routinely used to identify and isolate human hematopoietic stem/progenitor cells (HSPCs) for use clinically in bone marrow transplantation, but its function on these cells remains elusive. Glycoprotein ligands on HSPCs help guide their migration to specialized microvascular beds in the bone marrow that express vascular selectins (E- and P-selectin). Here, we show that HSPC-enriched fractions from human hematopoietic tissue expressing CD34 (CD34pos) bound selectins, whereas those lacking CD34 (CD34neg) did not. An unbiased proteomics screen identified potential glycoprotein ligands on CD34pos cells revealing CD34 itself as a major vascular selectin ligand. Biochemical and CD34 knockdown analyses highlight a key role for CD34 in the first prerequisite step of cell migration, suggesting that it is not just a marker on these cells. Our results also entice future potential strategies to investigate the glycoforms of CD34 that discriminate normal HSPCs from leukemic cells and to manipulate CD34neg HSPC-enriched bone marrow or cord blood populations as a source of stem cells for clinical use.

rs1004819 is the main disease-associated IL23R variant in German Crohn's disease patients: combined analysis of IL23R, CARD15, and OCTN1/2 variants.

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Jürgen Glas

Full Text Available BACKGROUND: The IL23R gene has been identified as a susceptibility gene for inflammatory bowel disease (IBD in the North American population. The aim of our study was to test this association in a large German IBD cohort and to elucidate potential interactions with other IBD genes as well as phenotypic consequences of IL23R variants. METHODS: Genomic DNA from 2670 Caucasian individuals including 833 patients with Crohn's disease (CD, 456 patients with ulcerative colitis (UC, and 1381 healthy unrelated controls was analyzed for 10 IL23R SNPs. Genotyping included the NOD2 variants p.Arg702Trp, p.Gly908Arg, and p.Leu1007fsX1008 and polymorphisms in SLC22A4/OCTN1 (1672 C-->T and SLC22A5/OCTN2 (-207 G-->C. RESULTS: All IL23R gene variants analyzed displayed highly significant associations with CD. The strongest association was found for the SNP rs1004819 [P = 1.92x10(-11; OR 1.56; 95 % CI (1.37-1.78]. 93.2% of the rs1004819 TT homozygous carriers as compared to 78% of CC wildtype carriers had ileal involvement [P = 0.004; OR 4.24; CI (1.46-12.34]. The coding SNP rs11209026 (p.Arg381Gln was protective for CD [P = 8.04x10(-8; OR 0.43; CI (0.31-0.59]. Similar, but weaker associations were found in UC. There was no evidence for epistasis between the IL23R gene and the CD susceptibility genes CARD15 and SLC22A4/5. CONCLUSION: IL23R is an IBD susceptibility gene, but has no epistatic interaction with CARD15 and SLC22A4/5. rs1004819 is the major IL23R variant associated with CD in the German population, while the p.Arg381Gln IL23R variant is a protective marker for CD and UC.

Revealing the mechanisms of protein disorder and N-glycosylation in CD44-hyaluronan binding using molecular simulation

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Olgun eGuvench

2015-06-01

Full Text Available The extracellular N-terminal hyaluronan binding domain (HABD of CD44 is a small globular domain that confers hyaluronan (HA binding functionality to this large transmembrane glycoprotein. When recombinantly expressed by itself, HABD exists as a globular water-soluble protein that retains the capacity to bind HA. This has enabled atomic-resolution structural biology experiments that have revealed the structure of HABD and its binding mode with oligomeric HA. Such experiments have also pointed to an order-to-disorder transition in HABD that is associated with HA binding. However, it had remained unclear how this structural transition was involved in binding since it occurs in a region of HABD distant from the HA-binding site. Furthermore, HABD is known to be N-glycosylated, and such glycosylation can diminish HA binding when the associated N-glycans are capped with sialic acid residues. The intrinsic flexibility of disordered proteins and of N-glycans makes it difficult to apply experimental structural biology approaches to probe the molecular mechanisms of how the order-to-disorder transition and N-glycosylation can modulate HA binding by HABD. We review recent results from molecular dynamics simulations that provide atomic-resolution mechanistic understanding of such modulation to help bridge gaps between existing experimental binding and structural biology data. Findings from these simulations include: Tyr42 may function as a molecular switch that converts the HA binding site from a low affinity to a high affinity state; in the partially-disordered form of HABD, basic amino acids in the C-terminal region can gain sufficient mobility to form direct contacts with bound HA to further stabilize binding; and terminal sialic acids on covalently-attached N-glycans can form charge-paired hydrogen bonding interactions with basic amino acids that could otherwise bind to HA, thereby blocking HA binding to glycosylated CD44 HABD.

55K isoform of CDK9 associates with Ku70 and is involved in DNA repair

International Nuclear Information System (INIS)

Liu, Hongbing; Herrmann, Christine H.; Chiang, Karen; Sung, Tzu-Ling; Moon, Sung-Hwan; Donehower, Lawrence A.; Rice, Andrew P.

2010-01-01

Positive elongation factor b (P-TEFb) is a cellular protein kinase that is required for RNA polymerase II (RNAP II) transcriptional elongation of protein coding genes. P-TEFb is a set of different molecular complexes, each containing CDK9 as the catalytic subunit. There are two isoforms of the CDK9 protein - the major 42 KDa CDK9 isoform and the minor 55KDa isoform that is translated from an in-frame mRNA that arises from an upstream transcriptional start site. We found that shRNA depletion of the 55K CDK9 protein in HeLa cells induces apoptosis and double-strand DNA breaks (DSBs). The levels of apoptosis and DSBs induced by the depletion were reduced by expression of a 55K CDK9 protein variant resistant to the shRNA, indicating that these phenotypes are the consequence of depletion of the 55K protein and not off-target effects. We also found that the 55K CDK9 protein, but not the 42K CDK9 protein, specifically associates with Ku70, a protein involved in DSB repair. Our findings suggest that the 55K CDK9 protein may function in repair of DNA through an association with Ku70.

Functional variants in the LRRK2 gene confer shared effects on risk for Crohn's disease and Parkinson's disease.

Science.gov (United States)

Hui, Ken Y; Fernandez-Hernandez, Heriberto; Hu, Jianzhong; Schaffner, Adam; Pankratz, Nathan; Hsu, Nai-Yun; Chuang, Ling-Shiang; Carmi, Shai; Villaverde, Nicole; Li, Xianting; Rivas, Manual; Levine, Adam P; Bao, Xiuliang; Labrias, Philippe R; Haritunians, Talin; Ruane, Darren; Gettler, Kyle; Chen, Ernie; Li, Dalin; Schiff, Elena R; Pontikos, Nikolas; Barzilai, Nir; Brant, Steven R; Bressman, Susan; Cheifetz, Adam S; Clark, Lorraine N; Daly, Mark J; Desnick, Robert J; Duerr, Richard H; Katz, Seymour; Lencz, Todd; Myers, Richard H; Ostrer, Harry; Ozelius, Laurie; Payami, Haydeh; Peter, Yakov; Rioux, John D; Segal, Anthony W; Scott, William K; Silverberg, Mark S; Vance, Jeffery M; Ubarretxena-Belandia, Iban; Foroud, Tatiana; Atzmon, Gil; Pe'er, Itsik; Ioannou, Yiannis; McGovern, Dermot P B; Yue, Zhenyu; Schadt, Eric E; Cho, Judy H; Peter, Inga

2018-01-10

Crohn's disease (CD), a form of inflammatory bowel disease, has a higher prevalence in Ashkenazi Jewish than in non-Jewish European populations. To define the role of nonsynonymous mutations, we performed exome sequencing of Ashkenazi Jewish patients with CD, followed by array-based genotyping and association analysis in 2066 CD cases and 3633 healthy controls. We detected association signals in the LRRK2 gene that conferred risk for CD (N2081D variant, P = 9.5 × 10 -10 ) or protection from CD (N551K variant, tagging R1398H-associated haplotype, P = 3.3 × 10 -8 ). These variants affected CD age of onset, disease location, LRRK2 activity, and autophagy. Bayesian network analysis of CD patient intestinal tissue further implicated LRRK2 in CD pathogenesis. Analysis of the extended LRRK2 locus in 24,570 CD cases, patients with Parkinson's disease (PD), and healthy controls revealed extensive pleiotropy, with shared genetic effects between CD and PD in both Ashkenazi Jewish and non-Jewish cohorts. The LRRK2 N2081D CD risk allele is located in the same kinase domain as G2019S, a mutation that is the major genetic cause of familial and sporadic PD. Like the G2019S mutation, the N2081D variant was associated with increased kinase activity, whereas neither N551K nor R1398H variants on the protective haplotype altered kinase activity. We also confirmed that R1398H, but not N551K, increased guanosine triphosphate binding and hydrolyzing enzyme (GTPase) activity, thereby deactivating LRRK2. The presence of shared LRRK2 alleles in CD and PD provides refined insight into disease mechanisms and may have major implications for the treatment of these two seemingly unrelated diseases. Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

Hyaluronic Acid Immobilized Polyacrylamide Nanoparticle Sensors for CD44 Receptor Targeting and pH Measurement in Cells

DEFF Research Database (Denmark)

Sun, Honghao; Benjaminsen, Rikke Vicki; Almdal, Kristoffer

2012-01-01

Our ability to design receptor-targeted nanocarriers aimed at drug release after endocytosis is limited by the current knowledge of intracellular nanoparticle (NP) trafficking. It is not clear if NP size, surface chemistry, and/or targeting of cell surface receptors changes the intracellular fate...... of NPs; i.e., will all NPs enter acidic compartments and eventually end up in lysosomes or are there escape mechanisms or receptor-specific signaling that can be induced to change the cellular processing of an internalized NP? To give new insight into the intracellular trafficking of NPs that target...... nanosensors indicates that the intracellular trafficking is aimed at lysosomes regardless of whether CD44 receptor-specific or unspecific uptake is induced....

A single amino-acid change in a highly conserved motif of gp41 elicits HIV-1 neutralization and protects against CD4 depletion.

Science.gov (United States)

Petitdemange, Caroline; Achour, Abla; Dispinseri, Stefania; Malet, Isabelle; Sennepin, Alexis; Ho Tsong Fang, Raphaël; Crouzet, Joël; Marcelin, Anne-Geneviève; Calvez, Vincent; Scarlatti, Gabriella; Debré, Patrice; Vieillard, Vincent

2013-09-01

The induction of neutralizing antibodies against conserved regions of the human immunodeficiency virus type 1 (HIV-1) envelope protein is a major goal of vaccine strategies. We previously identified 3S, a critical conserved motif of gp41 that induces the NKp44L ligand of an activating NK receptor. In vivo, anti-3S antibodies protect against the natural killer (NK) cell-mediated CD4 depletion that occurs without efficient viral neutralization. Specific substitutions within the 3S peptide motif were prepared by directed mutagenesis. Virus production was monitored by measuring the p24 production. Neutralization assays were performed with immune-purified antibodies from immunized mice and a cohort of HIV-infected patients. Expression of NKp44L on CD4(+) T cells and degranulation assay on activating NK cells were both performed by flow cytometry. Here, we show that specific substitutions in the 3S motif reduce viral infection without affecting gp41 production, while decreasing both its capacity to induce NKp44L expression on CD4(+) T cells and its sensitivity to autologous NK cells. Generation of antibodies in mice against the W614 specific position in the 3S motif elicited a capacity to neutralize cross-clade viruses, notable in its magnitude, breadth, and durability. Antibodies against this 3S variant were also detected in sera from some HIV-1-infected patients, demonstrating both neutralization activity and protection against CD4 depletion. These findings suggest that a specific substitution in a 3S-based immunogen might allow the generation of specific antibodies, providing a foundation for a rational vaccine that combine a capacity to neutralize HIV-1 and to protect CD4(+) T cells.

Role of CD56 in Normal Kidney Development and Wilms Tumorigenesis

DEFF Research Database (Denmark)

Yap, Li-Wei; Brok, Jesper; Pritchard-Jones, Kathy

2017-01-01

The cell-surface glycoprotein CD56 has three major isoforms that play important roles in cell adhesion and signaling, which may promote cell proliferation, differentiation, survival, or migration. It is an important molecule in normal kidney development and acts as a key marker in Wilms tumor stem...

Role of the Phosphorylation of mTOR in the Differentiation of AML Cells Triggered with CD44 Antigen

KAUST Repository

Darwish, Manar M

2013-05-01

Acute myeloid leukemia (AML) is a hematological disorder characterized by blockage of differentiation of myeloblasts. To date, the main therapy for AML is chemotherapy. Yet, studies are seeking a better treatment to enhance the survival rate of patients and minimize the relapsing of the disease. Since the major problem in these cells is that they are arrested in cellular differentiation, drugs that could induce their differentiation have proven to be efficient and of major interest for AML therapy. CD44 triggering appeared as a promising target for AML therapy as it has been shown that specific monoclonal antibodies, such as A3D8 and H90, reversed the blockage of differentiation, inhibited the proliferation of all AML subtypes, and in some cases, induced cell apoptosis. Studies conducted in our laboratory have added strength to these antibodies as potential treatment for AML. Indeed, our laboratory found that treating HL60 cells with A3D8 shows a decrease in the phosphorylation of the mammalian target of Rapamycin (mTOR) kinase correlated with the inhibition of proliferation/induction of differentiation of AML cells.The relationship between the induction of differentiation and the inhibition of proliferation and the decrease of mTOR phosphorylation remains to be clarified. To study the importance of the de-phosphorylation of mTOR and the observed effect of CD44 triggering on differentiation and/or proliferation, we sought to prepare phospho-mimic mutants of the mTOR kinase that will code for a constitutively phosphorylated form of mTOR and used two main methods to express this mutant in HL60 cells: lentiviral and simple transfection (cationic-liposomal transfection).

HLA-G allelic variants are associated with differences in the HLA-G mRNA isoform profile and HLA-G mRNA levels

DEFF Research Database (Denmark)

Hviid, Thomas Vauvert F; Hylenius, Sine; Rørbye, Christina

2003-01-01

between mother and fetus in several ways. Finally, the expression of membrane-bound HLA-G and soluble HLA-G has been proposed to influence the outcome of pregnancy, and an aberrant HLA-G expression in pre-eclamptic placentas and spontaneous abortions has been reported. Here, an association between certain...... HLA-G polymorphisms and the mRNA levels of the different alternatively spliced HLA-G isoforms in first trimester trophoblast cell populations is reported. Several alternatively spliced HLA-G mRNA isoforms, including a 14-bp polymorphism in the 3'UTR end (exon 8) of the HLA-G gene, are expressed...

Two Domains of Vimentin Are Expressed on the Surface of Lymph Node, Bone and Brain Metastatic Prostate Cancer Lines along with the Putative Stem Cell Marker Proteins CD44 and CD133

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Steinmetz, Nicole F. [Case Western Reserve University, Department of Biomedical Engineering, 10900 Euclid Ave, Cleveland, OH 44106 (United States); Maurer, Jochen [Sanford-Burnham, Medical Research Institute, 10901 North Torrey Pines Road, La Jolla, CA 92037 (United States); Sheng, Huiming [Torrey Pines Institute for Molecular Studies, Division of Immune Regulation, 3550 General Atomics Court, San Diego, CA 92121 (United States); Bensussan, Armand [INSERM U976, Hôpital Saint Louis, F-75475 Paris (France); Department of Immunology, Dermatology and Oncology, Univ Paris Diderot, Sorbonne Paris Cité, UMRS976 F-75475 Paris (France); Maricic, Igor; Kumar, Vipin [Torrey Pines Institute for Molecular Studies, Laboratory of Autoimmunity, 3550 General Atomics Court, San Diego, CA 92121 (United States); Braciak, Todd A., E-mail: tbraciak@tpims.org [Torrey Pines Institute for Molecular Studies, Division of Immune Regulation, 3550 General Atomics Court, San Diego, CA 92121 (United States)

2011-07-13

Vimentin was originally identified as an intermediate filament protein present only as an intracellular component in many cell types. However, this protein has now been detected on the surface of a number of different cancer cell types in a punctate distribution pattern. Increased vimentin expression has been indicated as an important step in epithelial-mesenchymal transition (EMT) required for the metastasis of prostate cancer. Here, using two vimentin-specific monoclonal antibodies (SC5 and V9 directed against the coil one rod domain and the C-terminus of the vimentin protein, respectively), we examined whether either of these domains would be displayed on the surface of three commonly studied prostate cancer cell lines isolated from different sites of metastases. Confocal analysis of LNCaP, PC3 and DU145 prostate cancer cell lines (derived from lymph node, bone or brain prostate metastases, respectively) demonstrated that both domains of vimentin are present on the surface of these metastatic cancer cell types. In addition, flow cytometric analysis revealed that vimentin expression was readily detected along with CD44 expression but only a small subpopulation of prostate cancer cells expressed vimentin and the putative stem cell marker CD133 along with CD44. Finally, Cowpea mosaic virus (CPMV) nanoparticles that target vimentin could bind and internalize into tested prostate cancer cell lines. These results demonstrate that at least two domains of vimentin are present on the surface of metastatic prostate cancer cells and suggest that vimentin could provide a useful target for nanoparticle- or antibody- cancer therapeutic agents directed against highly invasive cancer and/or stem cells.