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1.
Transl Med UniSa ; 22: 10-14, 2020 May.
Article in English | MEDLINE | ID: mdl-32523901

ABSTRACT

Digital ulcers (DUs) represent a severe and common complication occurring in patients affected by Systemic Sclerosis (SSc), with a consistent impact on the quality of life and often resulting in longer hospitalization than unaffected patients. Conventional treatment of SSc ulcers consists of both topical and systemic (oral or intravenous) pharmacological therapies. Several surgical options are also available, but there is overall a lack of official guidelines or recommendations. The aim of this study was to evaluate the efficacy of a novel local therapy based on polyurethane foam dressings, namely the Highly Hydrophilic Polyurethane Foam (HPF), in addition to the conventional pharmacological treatment, in a cohort of 41 SSc patients with at least one active ulcer. Our results showed that the addition of HPF to the conventional treatment based on systemic drugs induced i) a significant reduction in the number of active DUs (p=0.0034); ii) a significant reduction of the mean duration of ulcer-related hospitalization as compared with standard therapy (p=0.0001); iii) a significant improvement of patients' Quality of Life, as evaluated through the Scleroderma Health Assessment Questionnaire (SHAQ) (p=0.00011). Therefore, in our experience, the combined management of DUs can improve both the onset of new DUs and DU's healing thus leading to a better outcome.

2.
Transl Med UniSa ; 13: 33-41, 2015 Dec.
Article in English | MEDLINE | ID: mdl-27042431

ABSTRACT

Among lifestyle factors, nutrition is one of the most important determinants of health, and represents a pivotal element of cancer risk. Nonetheless, epidemiological evidences of the relationship between several cancers and specific foods and nutrients is still inadequate, and solid conclusions are missing. Indeed, caloric restriction without malnutrition is associated to cancer prevention. Food may be also the primary route of exposure to contaminants such as metals, persistent organic pollutants, and pesticides. Exposuredisease associations and the interplay with genetic susceptibility requires further studies on genetic variation, environment, lifestyle, and chronic disease in order to eliminate and reduce associated health risks, thus contributing to improve health outcomes for the population. A primary nutritional approach for Active and Healthy Ageing (AHA) has been developed by the Nutrition group of the European Innovation Partnership (EIP) on AHA. The working group on lifestyles of the Italian Ministry of Health has developed a comprehensive approach to adequate nutrition using a consensus methodology to collect and integrate the available evidences from the literature and from the Italian experiences at the regional level, to raise the interest of other experts and relevant stakeholders to outline and scale-up joint strategies for a primary nutritional approach to cancer prevention.

3.
Transl Med UniSa ; 8: 31-42, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24778996

ABSTRACT

Hypocellular or hypoplastic myelodysplastic syndromes (HMDS) are a distinct subgroup accounting for 10-15% of all MDS patients, that are characterized by the presence of bone marrow (BM) hypocellularity, various degree of dysmyelopoiesis and sometimes abnormal karyotype. Laboratory and clinical evidence suggest that HMDS share several immune-mediated pathogenic mechanisms with acquired idiopathic aplastic anemia (AA). Different immune-mediated mechanisms have been documented in the damage of marrow hematopoietic progenitors occurring in HMDS; they include oligoclonal expansion of cytotoxic T lymphocytes (CTLs), polyclonal expansion of various subtypes of T helper lymphocytes, overexpression of FAS-L and of the TNF-related apoptosis-inducing ligand (TRAIL), underexpression of Flice-like inhibitory protein long isoform (FLIPL) in marrow cells as well as higher release of Th1 cytokines, such as interferon-gamma (IFN-γ) and tumor necrosis factor-alpha (TNF-α). It has also been documented that some HMDS patients have higher frequency of polymorphisms linked both to high production of proinflammatory cytokines such as TNF-α and transforming growth factor-ß and to the inhibition of T-cell mediated immune responses such as interleukin-10, further suggesting that immune-mediated mechanisms similar to those seen in AA patients may also operate in HMDS. Clinically, the strongest evidence for immune-mediated hematopoietic suppression in some HMDS is the response to immunosuppression including mainly cyclosporine, anti-thymocyte globulin and/or cyclosporine, or alemtuzumab. Here we review all these immune mechanisms as well as the influence of this deranged cellular and humoral immunologic mileau on the initiation and possible progression of MDS. All these observations are pivotal not only for a better understanding of MDS pathophysiology, but also for their immediate clinical implications, eventually leading to the identification of MDS patients who may benefit from immunosuppression.

4.
Transl Med UniSa ; 6: 2-10, 2013.
Article in English | MEDLINE | ID: mdl-24251241

ABSTRACT

Overwhelming post-splenectomy infection (OPSI) is a rare medical emergency, mainly caused by encapsulated bacteria, shortly progressing from a mild flu-like syndrome to a fulminant, potentially fatal, sepsis. The risk of OPSI is higher in children and in patients with underlying benign or malignant hematological disorders. We retrospectively assessed OPSI magnitude in a high risk cohort of 162 adult splenectomized patients with malignant (19%) and non malignant (81%) hematological diseases, over a 25-year period: 59 of them splenectomized after immunization against encapsulated bacteria, and 103, splenectomized in the previous 12-year study, receiving only life-long oral penicillin prophylaxis. The influence of splenectomy on the immune system, as well as the incidence, diagnosis, risk factors, preventive measures and management of OPSI are also outlined. OPSI occurred in 7 patients (4%) with a median age of 37 years at time interval from splenectomy ranging from 10 days to 12 years. All OPSIs occurred in non immunized patients, except one fatal Staphylococcus aureus -mediated OPSI in a patient adequately immunized before splenectomy. Our analysis further provides evidence that OPSI is a lifelong risk and that current immune prophylaxis significantly decreases OPSI development. Improvement in patients' education about long-term risk of OPSI and increased physician awareness to face a potentially lethal medical emergency, according to the current surviving sepsis guidelines, represent mandatory strategies for preventing and managing OPSI appropriately.

5.
Transl Med UniSa ; 5: 7-13, 2013 Jan.
Article in English | MEDLINE | ID: mdl-23905076

ABSTRACT

Osteoporosis and avascular necrosis (AVN) are long-lasting and debilitating complications of hematopoietic stem cell transplantation (HSCT). We describe the magnitude of bone loss, AVN and impairment in osteogenic cell compartment following autologous (auto) and allogeneic (allo) HSCT, through the retrospective bone damage revaluation of 100 (50 auto- and 50 allo-HSCT) long-term survivors up to 15 years after transplant. Current treatment options for the management of these complications are also outlined. We found that auto- and allo-HSCT recipients show accelerated bone mineral loss and micro-architectural deterioration during the first years after transplant. Bone mass density (BMD) at the lumbar spine, but not at the femur neck, may improve in some patients after HSCT, suggesting more prolonged bone damage in cortical bone. Phalangeal BMD values remained low for even more years, suggesting persistent bone micro-architectural alterations after transplant. The incidence of AVN was higher in allo-HSCT recipients compared to auto-HSCT recipients. Steroid treatment length, but not its cumulative dose was associated with a higher incidence of bone loss. Allo-HSCT recipients affected by chronic graft versus host disease seem to be at greater risk of continuous bone loss and AVN development. Reduced BMD and higher incidence of AVN was partly related to a reduced regenerating capacity of the normal marrow osteogenic cell compartment. Our results suggest that all patients after auto-HSCT and allo-HSCT should be evaluated for their bone status and treated with anti-resorptive therapy as soon as abnormalities are detected.

7.
Infez Med ; 20 Suppl 2: 13-8, 2012.
Article in English | MEDLINE | ID: mdl-23042001

ABSTRACT

Cell migration through the extracellular matrix (ECM) or endothelial cells is a basic process in several physiological and pathological events, including the immune host response to pathogens, both in the case of innate and adaptive immunity. The urokinase-type plasminogen activator (uPA) receptor (uPAR) is a GPI-anchored cell-surface receptor largely expressed on most of leukocytes, including monocytes/macrophages, granulocytes, immature dendritic cells. uPAR has been detected also in soluble and cleaved forms, which are increased in several pathologies. uPAR focuses the proteolytic activity of its ligand, the serine-protease uPA, on the cell membrane, thus promoting localized plasminogen activation and allowing the cell to degrade surrounding ECM and to move across physical barriers. However, the discovery that uPAR can bind with high affinity a component of the ECM, vitronectin (VN), and associates to cell surface molecules to activate signalling pathways inside the cells, largely expanded the role that uPAR can play in cell proliferation/survival and adhesion/migration, which are crucial events for an efficient immune response to infectious agents. This review is focused on the expression and possible functions of the various forms of uPAR in infectious diseases.


Subject(s)
Infections/immunology , Urokinase-Type Plasminogen Activator/immunology , Animals , Humans
8.
Infez Med ; 20 Suppl 2: 8-12, 2012.
Article in English | MEDLINE | ID: mdl-23042000

ABSTRACT

The 67 kDa high affinity laminin receptor (67LR) is a non integrin cell surface receptor for the extracellular matrix whose expression is increased in neoplastic cells and directly correlates with an enhanced invasive and metastatic potential. 67LR derives from homo- or hetero-dimerization of a 37 kDa cytosolic precursor (37LRP), by fatty acid acylation. Interestingly, 37LRP is a multifunctional protein involved in the translational machinery and has also been found in the nucleus, where it is tightly associated with nuclear structures. Acting as a receptor for laminin is not the only function of this protein; indeed, 67LR also acts as a receptor for viruses, such as Sindbis virus and Dengue virus, and is involved in the internalization of the prion protein. Here, we review the current understanding of the structure and function of this molecule, highlighting its role in cancer and infection diseases.


Subject(s)
Infections/etiology , Neoplasms/etiology , Receptors, Laminin/physiology , Ribosomal Proteins/physiology , Animals , Humans , Prions/physiology , Receptors, Laminin/chemistry , Ribosomal Proteins/chemistry
9.
Infez Med ; 20 Suppl 2: 19-25, 2012.
Article in English | MEDLINE | ID: mdl-23042002

ABSTRACT

Helicobacter pylori (H. pylori) is a microaerophilic, Gram-negative bacterium that affects more than half of the world's population. H. pylori has co-evolved with humans to be transmitted from person to person and to persistently colonize the stomach. A well-choreographed equilibrium between bacterial effectors and host responses permits microbial persistence and health of the host but confers risk of serious diseases. During its long coexistence with humans, H. pylori has evolved complex strategies to limit the degree and extent of gastric mucosal damage and inflammation as well as immune effector activity. In this complex strategy an important role is played by the interaction of H. pylori with a specific class of innate immune receptors, named N-formyl peptide receptor family (FPRs). In the last years several virulence factors have been studied in an effort to correlate bacterial phenotype with specific gastric manifestations and to clarify the pathogenetic mechanisms. Several peptides produced by H. pylori appear to be involved in inflammation associated with the infection. A particular interest has been focused on the Hp(2-20) peptide derived from the bacteria. Thus, aim of the article is to comment on some advances in the elucidation of specific interactions between the Hp(2-20) peptide and FPRs.


Subject(s)
Bacterial Proteins/immunology , Helicobacter Infections/immunology , Helicobacter pylori/pathogenicity , Peptide Fragments/immunology , Receptors, Formyl Peptide/immunology , Epithelial Cells/immunology , Humans , Immunity, Innate , Stomach/cytology
10.
Infez Med ; 20 Suppl 2: 26-34, 2012.
Article in English | MEDLINE | ID: mdl-23042003

ABSTRACT

The efficacy and safety of low dose oral valgancyclovir (VGCV) as cytomegalovirus (CMV) reactivation prophylaxis was retrospectively evaluated in 32 consecutive patients which underwent allogeneic HLA-matched related and unrelated hematopoietic stem cell transplantation (HSCT). Thirty HSCT recipients showed pretransplant CMV seropositivity. Fifteen received a myeloablative conditioning regimen, while seventeen patients received a reduced-intensity conditioning regimen. Twenty-one patients received graft-versus-host disease (GVHD) prophylaxis with cyclosporin A (CsA) and methotrexate (MTX), and the others CsA with MTX and anti-thymocyte globulin. CMV infection was monitored weekly using polymerase chain reaction (PCR). VGCV was administered orally at a dose of 450 mg daily for six months. Six patients developed a positive CMV-PCR on average 56 days after HSCT successfully treated with VGCV at 1800 mg/day, except one who developed fatal gastrointestinal CMV disease. At the time of CMV reactivation, four patients had been affected by grade II-IV acute GVHD and two by an extensive chronic GVHD. No significant specific VGCV-related toxicity was encountered. Seven patients presented hematological toxicity which did not require drug discontinuation. Our data suggest that low dose VGCV is safe and effective as CMV reactivation prophylaxis in allogeneic HSCT recipients. These results require further validation in prospective randomized studies.


Subject(s)
Antiviral Agents/administration & dosage , Cytomegalovirus Infections/etiology , Cytomegalovirus Infections/prevention & control , Cytomegalovirus/drug effects , Cytomegalovirus/physiology , Ganciclovir/analogs & derivatives , Hematopoietic Stem Cell Transplantation/adverse effects , Virus Activation/drug effects , Adolescent , Adult , Antiviral Agents/pharmacology , Female , Ganciclovir/administration & dosage , Ganciclovir/pharmacology , Humans , Male , Middle Aged , Prospective Studies , Valganciclovir , Young Adult
11.
Int J Immunopathol Pharmacol ; 23(3): 891-900, 2010.
Article in English | MEDLINE | ID: mdl-20943061

ABSTRACT

Systemic sclerosis (SSc) is characterized by excessive fibrosis throughout the body. There are two major subsets of SSc, diffuse cutaneous Systemic sclerosis (dSSc) and limited cutaneous Systemic sclerosis (lSSc). Fibroblasts play a key role in SSc. The expression and function of the urokinase (uPA)-mediated plasminogen activation (PA) system, a well-characterized system of serine-proteases involved in several pathological processes, has been investigated in SSc fibroblasts. The expression of the components of the PA system, including uPA, its type-1 and type-2 inhibitors (PAI-1 and PAI-2) and its receptor (uPAR), was examined by Western blot in fibroblasts from patients affected by limited and diffuse forms of SSc. uPA and PAI-1 secretion increased only in fibroblasts from lSSc lesions compared to normal fibroblasts. PAI-2 levels were decreased in fibroblasts from both SSc forms. Interestingly, fibroblasts from areas not adjacent to the lesions (not-affected) of the diffuse form showed reduced levels of PAI-1 and increased uPAR expression. Adhesion experiments showed reduced adherence to VN of fibroblasts from lSSc lesions and from non-affected areas of the diffuse form, as compared to normal controls. These results suggest a role for uPA and PAI-1 in the lSSc form, likely related to the activation of latent forms of cytokines and to the accumulation of ECM components, whereas a role for uPAR can be hypothesized in the evolvement of the diffuse form, based on its up-regulation in the non-affected areas.


Subject(s)
Fibroblasts/metabolism , Plasminogen Activators/biosynthesis , Scleroderma, Systemic/metabolism , Adult , Blotting, Western , Cell Adhesion , Cells, Cultured , Female , Humans , Indicators and Reagents , Middle Aged , Plasminogen Activator Inhibitor 1/biosynthesis , Plasminogen Activator Inhibitor 2/biosynthesis , Skin/cytology , Urokinase-Type Plasminogen Activator/biosynthesis , Vitronectin
12.
FEBS Lett ; 508(3): 379-84, 2001 Nov 23.
Article in English | MEDLINE | ID: mdl-11728456

ABSTRACT

We have recently reported that the urokinase-type plasminogen activator (uPA) up-regulates the cell surface expression of its own receptor (uPAR) in several cell types, independently of its enzymatic activity. uPA has no effect on kidney 293 cells which do not express uPAR and then cannot bind uPA. Kidney cells, transfected with the coding region of uPAR cDNA, express very large amounts of uPAR and respond to uPA stimulation by regulating uPAR both at mRNA and protein levels. uPA effect occurs also in the presence of the transcriptional inhibitor dichloro-ribobenzimidazole, whereas it is abolished by the protein synthesis inhibitor cycloheximide. Moreover, uPA-dependent uPAR up-regulation correlates with the increase of a complex between the coding region of uPAR mRNA and an unknown cellular factor. We then propose that uPA regulates uPAR expression at a post-transcriptional level, by promoting the binding of uPAR mRNA to a stabilizing factor.


Subject(s)
Receptors, Cell Surface/genetics , Urokinase-Type Plasminogen Activator/pharmacology , 3' Untranslated Regions , Cell Line , Cycloheximide/pharmacology , Humans , Isoflurophate/pharmacology , Promoter Regions, Genetic , Protein Synthesis Inhibitors/pharmacology , RNA, Messenger/genetics , RNA, Messenger/metabolism , Receptors, Cell Surface/metabolism , Receptors, Urokinase Plasminogen Activator , Reverse Transcriptase Polymerase Chain Reaction , Transcription, Genetic , Transfection , Up-Regulation , Urokinase-Type Plasminogen Activator/metabolism
13.
Eur J Histochem ; 45(3): 219-28, 2001.
Article in English | MEDLINE | ID: mdl-11759808

ABSTRACT

Fibroblasts are involved in all pathologies characterized by increased ExtraCellularMatrix synthesis, from wound healing to fibrosis. Granulocyte Macrophage-Colony Stimulating Factor (GM-CSF) is a cytokine isolated as an hemopoietic growth factor but recently indicated as a differentiative agent on endothelial cells. In this work we demonstrated the expression of the receptor for GM-CSF (GM-CSFR) on human normal skin fibroblasts from healthy subjects (NFPC) and on a human normal fibroblast cell line (NHDF) and we try to investigate the biological effects of this cytokine. Human normal fibroblasts were cultured with different doses of GM-CSF to study the effects of this factor on GM-CSFR expression, on cell proliferation and adhesion structures. In addition we studied the production of some Extra-Cellular Matrix (ECM) components such as Fibronectin, Tenascin and Collagen I. The growth rate of fibroblasts from healthy donors (NFPC) is not augmented by GM-CSF stimulation in spite of increased expression of the GM-CSFR. On the contrary, the proliferation of normal human dermal fibroblasts (NHDF) cell line seems more influenced by high concentration of GM-CSF in the culture medium. The adhesion structures and the ECM components appear variously influenced by GM-CSF treatment as compared to fibroblasts cultured in basal condition, but newly only NHDF cells are really induced to increase their synthesis activity. We suggest that the in vitro treatment with GM-CSF can shift human normal fibroblasts towards a more differentiated state, due or accompanied by an increased expression of GM-CSFR and that such "differentiation" is an important event induced by such cytokine.


Subject(s)
Dermis/drug effects , Fibroblasts/drug effects , Granulocyte-Macrophage Colony-Stimulating Factor/pharmacology , Adult , Blotting, Western , Cell Adhesion/drug effects , Cell Differentiation/drug effects , Cell Division/drug effects , Cell Line , Collagen Type I/biosynthesis , Dermis/metabolism , Dose-Response Relationship, Drug , Enzyme-Linked Immunosorbent Assay , Extracellular Matrix/drug effects , Extracellular Matrix/metabolism , Female , Fibroblasts/metabolism , Fibronectins/biosynthesis , Humans , Immunohistochemistry , Male , Receptors, Granulocyte-Macrophage Colony-Stimulating Factor/biosynthesis , Tenascin/biosynthesis
14.
FEBS Lett ; 476(3): 166-70, 2000 Jul 07.
Article in English | MEDLINE | ID: mdl-10913606

ABSTRACT

The expression of the receptor for the urokinase-type plasminogen activator (uPAR) can be regulated by several hormones, cytokines, tumor promoters, etc. Recently, it has been reported that uPAR is capable of transducing signals, even though it is lacking a transmembrane domain and a cytoplasmatic tail. We now report that uPAR cell surface expression can be positively regulated by its ligand, uPA, in thyroid cells. The effect of uPA is independent of its proteolytic activity, since inactivated uPA or its aminoterminal fragment have the same effects of the active enzyme. The increase of uPAR on the cell surface correlates with an increase of specific uPAR mRNA. Finally, uPA up-regulates uPAR expression also in other cell lines of different type and origin, thus suggesting that the regulatory role of uPA on uPAR expression is not restricted to thyroid cells, but it occurs in different tissues, both normal and tumoral.


Subject(s)
Receptors, Cell Surface/genetics , Receptors, Cell Surface/metabolism , Urokinase-Type Plasminogen Activator/metabolism , Base Sequence , Cell Line , DNA Primers/genetics , Humans , Ligands , RNA, Messenger/genetics , RNA, Messenger/metabolism , Receptors, Urokinase Plasminogen Activator , Thyroid Gland/metabolism , Tumor Cells, Cultured , Up-Regulation
15.
Thyroid ; 10(3): 201-9, 2000 Mar.
Article in English | MEDLINE | ID: mdl-10779134

ABSTRACT

We have recently shown that the rat hepatic lectin (RHL)-1 subunit of the asialoglycoprotein receptor (ASGPr) is expressed in the PC C13 differentiated thyroid cell line. To investigate in vivo the expression of RHL-1 and the ability of thyrotropin (TSH) to modulate its expression, reverse-transcriptase polymerase chain reaction (RT-PCR) and Western blot assays have been performed on thyroid extracts from rats treated with thyroxine (T4) or propylthiouracil (PTU), each of which modulates TSH levels. It is shown that RHL-1 expression is down-regulated by T4 (which decreases serum TSH) and upregulated by PTU (which increases serum TSH), at both mRNA and protein levels. The sensitivity of RHL-1 to neoplastic transformation of thyroid cells has been investigated. The RHL-1 expression pattern has been studied in PC C13 thyroid cells transformed by several oncogenes that induce different degrees of malignancy and dedifferentiation. RT-PCR and Western blot assays show that RHL-1 expression progressively decreases as PC C13 cells acquire a more transformed phenotype. Expression of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) mRNA, a housekeeping gene used as internal control to normalize RHL-1 mRNA content, exhibits no variations in the different PC C13 cell lines used. In addition, we show that both native and asialo-thyroglobulin (Tg) bind RHL-1 in vitro, and native Tg binds RHL-1 on the surface of PC C13 cells. After thyroid cells transformation, the surface expression of RHL-1 is inhibited in a measure that correlates with the mRNA and protein levels. Therefore, the RHL-1 inhibition at the mRNA, protein and plasma membrane expression follows a gradient that parallels the progressive acquisition of the fully transformed phenotype in the PC C13 system. The results reported in the present article, together with our previous data, suggest that RHL-1 expression could be regulated, at least in part, by the same transcription factors involved in the expression of the other molecules characteristic of the thyroid differentiated state.


Subject(s)
Cell Transformation, Neoplastic , Down-Regulation/physiology , Receptors, Cell Surface/genetics , Thyroid Gland/metabolism , Thyrotropin/pharmacology , Up-Regulation/physiology , Animals , Asialoglycoprotein Receptor , Cell Line , Male , Propylthiouracil/pharmacology , Protein Biosynthesis , Rats , Rats, Wistar , Reverse Transcriptase Polymerase Chain Reaction , Thyroid Gland/cytology , Thyroid Gland/drug effects , Thyroxine/pharmacology , Transcription, Genetic , Up-Regulation/drug effects
16.
Biochem Biophys Res Commun ; 268(1): 42-6, 2000 Feb 05.
Article in English | MEDLINE | ID: mdl-10652209

ABSTRACT

We have previously reported that the rat hepatic lectin-1 (RHL-1) subunit of rat asialoglycoprotein receptor (ASGPr), the endocytic receptor found on the basolateral surface of hepatocytes, was expressed in rat thyroid tissue and localized on the apical surface of polarized rat thyroid FRT cells. Here we show that PC Cl3 cells, a differentiated rat thyroid cell line, bound thyroglobulin (Tg) via ASGPr. In fact, both the bacterial recombinant carbohydrate recognition domain of RHL-1 (rCRD(RHL-1)) and the anti-rCRD(RHL-1) antibody markedly inhibited (125)I-Tg binding to the cell surface of PC Cl3 cells. Ligand blot assays with deglycosylated Tg show that the rCRD(RHL-1) was able to interact with Tg even after remotion of sugars. The region of Tg involved in the binding to RHL-1 was investigated by ligand blot assays with biotinylated rCRD(RHL-1) on thermolysin-digested native and desialated rat thyroglobulin. It is shown that the rCRD(RHL-1) specifically recognized a thyroglobulin fragment with an apparent M(r) of 68,000, corresponding to the amino-terminal part of the molecule. To our knowledge, this is the first report that attributes to the amino-terminal portion of Tg molecule, containing its earliest and major hormonogenic site, the function of binding to a cell surface receptor of the thyroid. Moreover, we show that oligosaccharides are not the only molecular signals for binding to RHL-1, but amino acidic determinants could also play a role.


Subject(s)
Receptors, Cell Surface/metabolism , Thyroglobulin/chemistry , Thyroglobulin/metabolism , Amino Acid Sequence , Animals , Asialoglycoprotein Receptor , Binding Sites/genetics , Cell Line , Cell Membrane/metabolism , Glycosylation , Molecular Weight , Peptide Fragments/chemistry , Peptide Fragments/genetics , Peptide Fragments/metabolism , Protein Binding , Rats , Recombinant Proteins/chemistry , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Thyroglobulin/genetics , Thyroid Gland/metabolism
17.
FEBS Lett ; 460(1): 32-6, 1999 Oct 22.
Article in English | MEDLINE | ID: mdl-10571056

ABSTRACT

The urokinase-type plasminogen activator uPA-R can regulate integrin functions by associating with several types of beta-subunit. We have recently shown that normal thyroid TAD-2 cells express both a native and a cleaved form of uPA-R which lacks the binding domain for uPA. We found this cleaved form to be present in reduced amounts in papillary and follicular thyroid carcinoma cells and completely absent in cells derived from an anaplastic thyroid carcinoma (ARO). We now report that in normal thyroid cells the intact form of uPA-R strongly associates with beta-1 integrins, whereas its cleaved form does not. uPA-R expressed by ARO cells shows a stronger resistance to the cleavage mediated by uPA, plasmin and chymotrypsin than does uPA-R expressed by normal thyroid cells. This resistance to cleavage correlates with the higher level of glycosylation of uPA-R of ARO cells as compared to that of cleavable uPA-R of normal thyroid cells. These results suggest that uPA-R cleavage, which occurs in several cell types, represents a mechanism regulating the interactions of uPA-R with integrins and, possibly, the subsequent integrin-mediated cell adhesion. Moreover we hypothesize that glycosylation regulates uPA-R cleavage and, indirectly, its interaction with integrins.


Subject(s)
Integrins/metabolism , Receptors, Cell Surface/metabolism , Amidohydrolases/metabolism , Cell Line , Chymotrypsin/metabolism , Glycosylation , Humans , Peptide-N4-(N-acetyl-beta-glucosaminyl) Asparagine Amidase , Plasmids , Receptors, Urokinase Plasminogen Activator , Thyroid Gland , Transfection
18.
Clin Cancer Res ; 5(6): 1465-72, 1999 Jun.
Article in English | MEDLINE | ID: mdl-10389934

ABSTRACT

Lodgement, proliferation, and migration of leukemic cells within bone marrow (BM) microenvironment involves adhesion of these cells to the BM extracellular matrix molecules fibronectin and laminin. The 67-kDa laminin receptor (67LR) is a nonintegrin protein with high affinity for laminin, which plays a critical role in basement membrane invasion and metastasis of cancer cells. By Western blotting, we documented that 67LR was strongly expressed in myelomonocytic THP1 and histiocytic U937 cells and was weakly expressed in promyelocytic HL-60 cells. In HL-60 cells, 67LR expression almost disappeared after retinoic-induced granulocytic differentiation, whereas it strongly increased after phorbol ester-induced monocytic differentiation. We did not detect 67LR expression in normal BM hematopoietic cells, in precursor-B acute lymphoblastic leukemia, in chronic lymphocytic leukemia, or in chronic myeloid leukemia in chronic phase. By contrast, we detected enhanced 67LR expression in 40% of 53 de novo acute myeloid leukemias (AMLs), which frequently exhibited monocytic or myelomonocytic morphology and expressed CD14 and CD11a (P < 0.05). Using a colorimetric assay, we found that the expression pattern of this receptor corresponded to a higher adhesion to laminin; the adhesion was specific because in vitro addition to laminin-coated wells of recombinant 37-kDa laminin receptor precursor (37LRP), which is the cytoplasmic precursor containing both laminin-binding domains of cell surface 67LR, significantly reduced laminin binding of AML cells. The expression of 67LR on AML cell surface did not correlate with other differentiation and integrin antigens such as CD7, CD13, CD33, CD34, CD11b, CD11c, CD49d, CD49e, CD45RA, and CD45RO. In contrast with 67LR behavior in solid tumors, no statistically significant difference was found between 67LR expression and any hematological characteristic of the disease at diagnosis, nor between 67LR expression and outcome of the disease as measured by complete remission rate, disease-free survival, or overall survival. In conclusion, our results indicate that 67LR expression mediates specific adhesion to laminin and that the detection of this molecule may be a valuable addition to other lineage-associated antigens in identifying monocytic-oriented AML.


Subject(s)
Laminin/metabolism , Leukemia, Myeloid/metabolism , Monocytes/metabolism , Receptors, Laminin/biosynthesis , Acute Disease , Adolescent , Adult , Aged , Antigens, CD/biosynthesis , Blotting, Western , Cell Adhesion/physiology , Cell Differentiation/drug effects , Cell Differentiation/physiology , Cells, Cultured , Female , HL-60 Cells , Humans , Immunophenotyping , Leukemia, Myeloid/diagnosis , Leukemia, Myeloid/mortality , Male , Middle Aged , Monocytes/cytology , Prognosis , Receptors, Laminin/physiology , Survival Rate , Tetradecanoylphorbol Acetate/pharmacology , Tretinoin/pharmacology
19.
Cytogenet Cell Genet ; 84(3-4): 220-4, 1999.
Article in English | MEDLINE | ID: mdl-10393436

ABSTRACT

The human teratocarcinoma derived growth factor 1 (TDGF1) gene maps on chromosome (Chr) 3p21.3. One pseudogene (TDGF3) maps on Chr Xq21-->q22. We now report the nucleotide sequence and chromosome location of three additional TDGF pseudogenes. The three new sequences (TDGF2, TDGF4 and TDGF5) are truncated at the 5' end and have accumulated several point mutations, deletions and insertions. TDGF2, TDGF4 and TDGF6 map on Chrs 2q37, 6p25 and 3q22, respectively. Finally, Southern blot analysis of DNA from normal individuals shows a highly variable restriction pattern of the TDGF sequences.


Subject(s)
Chromosomes, Human/genetics , Epidermal Growth Factor , Membrane Glycoproteins , Neoplasm Proteins/genetics , Physical Chromosome Mapping , Pseudogenes/genetics , Alu Elements/genetics , Base Sequence , Blotting, Southern , Chromosomes, Artificial, Yeast/genetics , Chromosomes, Human, Pair 2/genetics , Chromosomes, Human, Pair 3/genetics , Chromosomes, Human, Pair 6/genetics , Cloning, Molecular , Exons/genetics , GPI-Linked Proteins , Humans , Hybrid Cells , In Situ Hybridization, Fluorescence , Intercellular Signaling Peptides and Proteins , Introns/genetics , Mutation , Templates, Genetic
20.
Biochimie ; 81(4): 355-8, 1999 Apr.
Article in English | MEDLINE | ID: mdl-10401669

ABSTRACT

The urokinase-type plasminogen activator receptor (uPA-R) focuses the proteolytic activity of its ligand, the urokinase-type plasminogen activator (uPA), on the cell surface, and can also act as an adhesion receptor for vitronectin (VTN). uPA increases uPA-R affinity for VTN and is also able to cleave its receptor. We have previously shown that uPA-R is involved in the adhesion of normal thyroid cells to VTN. In the present report, we have investigated the effect of uPA on normal thyroid cell adhesion to some extracellular matrix (ECM) components. We show that a short-term treatment with uPA does not change normal thyroid cell adhesion to fibronectin (FNT), collagen (CGN), laminin (LMN) and VTN. The prolongation of uPA treatment increases cell adhesion to VTN, and, less efficiently, to other ECM components. Since the short term uPA treatment causes a partial cleavage of uPA-R, that does not increase with time, the observed increase in cell adhesivity cannot be related to the cleavage of uPA-R. We show that the adhesion improvement after the long term uPA treatment is instead due to a strong increase of the cell-surface expression of the integrin beta3 and a moderate increase of the integrin alpha(v). Both alpha(v) beta3 and alpha(v) beta1 are integrinic receptors for VTN.


Subject(s)
Cell Adhesion/drug effects , Extracellular Matrix/metabolism , Thyroid Gland/metabolism , Urokinase-Type Plasminogen Activator/metabolism , Antigens, CD/biosynthesis , Cell Adhesion/physiology , Cell Line , Humans , Integrin alphaV , Integrin beta1/biosynthesis , Integrin beta3 , Platelet Membrane Glycoproteins/biosynthesis , Receptors, Cell Surface/metabolism , Receptors, Urokinase Plasminogen Activator , Thyroid Gland/cytology , Urokinase-Type Plasminogen Activator/pharmacology
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