RESUMO
BACKGROUND: Cytokine-release reactions (CRR) induced by platinum-based chemotherapy, manifesting with fever, chills, and rigors, are poorly understood and not easily prevented by usual premedication or desensitization. OBJECTIVE: To gain a better understanding of platinum-induced CRR and to explore the use of anakinra as a tool to prevent its clinical manifestations. METHODS: A cytokine and chemokine panel was obtained before and after platinum infusion in 3 cases with a mixed (immunoglobulin E-mediated and CRR) platinum-induced hypersensitivity reaction and in 5 controls either tolerant or with an immunoglobulin E-mediated platinum-induced hypersensitivity reaction. Anakinra was given as premedication in the 3 CRR cases. RESULTS: Cytokine-release reaction was associated with a marked release of interleukin (IL)-2, IL-5, IL-6, IL-10, and tumor necrosis factor-É in all cases whereas only IL-2 and IL-10 increased in some controls after platinum infusion, and to a lesser extent than in cases. Anakinra seemed to block CRR symptoms in 2 cases. In the third case, who initially had CRR symptoms despite anakinra, tolerance to oxaliplatin appeared to develop after repeated re-exposures, as suggested by the decreasing levels of cytokines after oxaliplatin, except IL-10, and the capacity to progressively shorten the desensitization protocol and taper the premedication, in addition to the negativization of the oxaliplatin skin test result. CONCLUSION: In patients with platinum-induced CRR, anakinra could be a useful premedication to block its clinical manifestations, and monitoring of IL-2, IL-5, IL-6, IL-10, and tumor necrosis factor-É could help predict tolerance development, thereby allowing safe adjustments to the desensitization protocol and premedication.
Assuntos
Antineoplásicos , Hipersensibilidade a Drogas , Hipersensibilidade , Humanos , Oxaliplatina/efeitos adversos , Antineoplásicos/efeitos adversos , Proteína Antagonista do Receptor de Interleucina 1/uso terapêutico , Platina/uso terapêutico , Interleucina-2/uso terapêutico , Interleucina-10 , Interleucina-6 , Fator de Necrose Tumoral alfa , Interleucina-5 , Compostos Organoplatínicos/efeitos adversos , Hipersensibilidade a Drogas/tratamento farmacológico , Citocinas , Hipersensibilidade/tratamento farmacológico , Imunoglobulina ERESUMO
Placental malaria is a serious problem in sub-Saharan Africa. Young women are particular susceptible to contracting this form of malaria during their first or second pregnancy despite previously acquired immunity from past infections. Placental malaria is caused by Plasmodium falciparum parasites expressing VAR2CSA on the erythrocyte surface. This protein adheres to a low-sulfated chondroitin sulfate-A found in placental tissue causing great harm to both mother and developing fetus. In rare cases, the localization of infected erythrocytes to the placenta can even result in the vertical transmission of malaria. In an effort to better understand this infection, chondroitin sulfate was isolated from the cotyledon part of the placenta, which should be accessible for parasite adhesion, as well as two non-accessible parts of the placenta to serve as controls. The placental chondroitin sulfate structures and their VAR2CSA binding were characterized. All portions of human placenta contained sufficient amounts of the appropriate low-sulfated chondroitin sulfate-A to display high-affinity binding to a recombinant truncated VAR2CSA construct, as determined using surface plasmon resonance. The cotyledon is the only placental tissue accessible to parasites in the bloodstream, suggesting it is the primary receptor for parasite infected red blood cells.
Assuntos
Antígenos de Protozoários/metabolismo , Eritrócitos/metabolismo , Glicosaminoglicanos/metabolismo , Placenta/química , Sítios de Ligação , Sulfatos de Condroitina/química , Eritrócitos/parasitologia , Feminino , Glicosaminoglicanos/química , Glicosaminoglicanos/isolamento & purificação , Humanos , Peso Molecular , Gravidez , Ressonância de Plasmônio de SuperfícieRESUMO
O-sulfotransferases (OSTs) are critical enzymes in the cellular biosynthesis of the biologically and pharmacologically important heparan sulfate and heparin. Recently, these enzymes have been cloned and expressed in bacteria for application in the chemoenzymatic synthesis of glycosaminoglycan-based drugs. OST activity assays have largely relied on the use of radioisotopic methods using [(35)S] 3'-phosphoadenosine-5'-phosphosulfate and scintillation counting. Herein, we examine alternative assays that are more compatible with a biomanufacturing environment. A high throughput microtiter-based approach is reported that relies on a coupled bienzymic colorimetric assay for heparan sulfate and heparin OSTs acting on polysaccharide substrates using arylsulfotransferase-IV and p-nitrophenylsulfate as a sacrificial sulfogroup donor. A second liquid chromatography-mass spectrometric assay, for heparan sulfate and heparin OSTs acting on structurally defined oligosaccharide substrates, is also reported that provides additional information on the number and positions of the transferred sulfo groups within the product. Together, these assays allow quantitative and mechanistic information to be obtained on OSTs that act on heparan sulfate and heparin precursors.
Assuntos
Bioensaio , Heparina/química , Heparitina Sulfato/química , Sulfotransferases/análise , Sequência de Carboidratos , Cromatografia Líquida , Colorimetria , Cinética , Espectrometria de Massas , Dados de Sequência Molecular , Nitrobenzenos/química , Especificidade por Substrato , Sulfotransferases/químicaRESUMO
Adeno-associated virus (AAV) is a key candidate in the development of gene therapy. In this work, we used surface plasmon resonance spectroscopy to study the interaction between AAV and heparin and other glycosaminoglycans (GAGs). Surface plasmon resonance results revealed that heparin binds to AAV with an extremely high affinity. Solution competition studies showed that binding of AAV to heparin is chain length-dependent. AAV prefers to bind full chain heparin. All sulfo groups (especially N-sulfo and 6-O-sulfo groups) on heparin are important for the AAV-heparin interaction. Higher levels of sulfo group substitution in GAGs enhance their binding affinities. Atomic force microscopy was also performed to image AAV-2 in a complex with heparin.
Assuntos
Dependovirus/metabolismo , Glicosaminoglicanos/metabolismo , Heparina/metabolismo , Animais , Heparina/análogos & derivados , Microscopia de Força Atômica , Ressonância de Plasmônio de Superfície , SuínosRESUMO
Heparin and related heparan sulfate interact with a number of cytokines and growth factors, thereby playing an essential role in many physiological and pathophysiological processes by involving both signal transduction and the regulation of the tissue distribution of cytokines/growth factors. Follistatin (FS) is an autocrine protein with a heparin-binding motif that serves to regulate the cell proliferative activity of the paracrine hormone, and member of the TGF-ß family, activin A (ActA). Follistatin is currently under investigation as an antagonist of another TGF-ß family member, myostatin (Mstn), for the promotion of muscle growth in diseases associated with muscle atrophy. In this study, we employ surface plasmon resonance (SPR) spectroscopy to dissect the binding interactions between the heparin polysaccharide and both free follistatin (FS288) and its complexes (FS288-ActA and FS288-Mstn). FS288 complexes show much higher heparin binding affinity than FS288 alone. SPR solution competition studies using heparin oligosaccharides showed that the binding of FS288 and its complex to heparin is dependent on chain length. Full chain heparin or large oligosaccharides, having 18-20 sugar residues, show the highest binding activity for FS288 and the FS288-ActA complex, whereas smaller heparin molecules could interact with the FS288-Mstn complex. These interactions were also analyzed in normal physiological buffers and at different salt concentrations and pH values. Unbound follistatin was much more sensitive to all salt concentrations of >150 mM. The binding of heparin to the FS288-ActA complex was disrupted at 500 mM salt, whereas it was actually strengthened for the FS288-Mstn complex. At acidic pH values, binding of heparin to FS288 and the FS288-ActA complex was enhanced. While slightly acidic pH values (pH 6.2 and 5.2) enhanced the binding of the FS288-Mstn complex to heparin, at pH 4 heparin binding was inhibited. Overall, these studies demonstrate that binding of a specific ligand to FS288 differentially regulates its affinity and behavior for heparin molecules.
Assuntos
Folistatina/metabolismo , Heparina/metabolismo , Ressonância de Plasmônio de Superfície/métodos , Ativinas/química , Ativinas/metabolismo , Folistatina/química , Heparina/química , Humanos , Concentração de Íons de Hidrogênio , Cinética , Ligantes , Miostatina/química , Miostatina/metabolismo , Ligação ProteicaRESUMO
Seven commercial heparin active pharmaceutical ingredients and one commercial low molecular weight from different manufacturers were characterized with a view profiling their physicochemical properties. All heparins had similar molecular weight properties as determined by polyacrylamide gel electrophoresis (M(N), 10-11 kDa; M(W), 13-14 kDa; polydispersity (PD), 1.3-1.4) and by size exclusion chromatography (M(N), 14-16 kDa; M (W), 21-25 kDa; PD, 1.4-1.6). one-dimensional (1)H- and (13)C-nuclear magnetic resonance (NMR) evaluation of the heparin samples was performed, and peaks were fully assigned using two-dimensional NMR. The percentage of glucosamine residues with 3-O-sulfo groups and the percentage of N-sulfo groups and N-acetyl groups ranged from 5.8-7.9%, 78-82%, to 13-14%, respectively. There was substantial variability observed in the disaccharide composition, as determined by high performance liquid chromatography (HPLC)-mass spectral analysis of heparin lyase I-III digested heparins. Heparin oligosaccharide mapping was performed using HPLC following separate treatments with heparin lyase I, II, and III. These maps were useful in qualitatively and quantitatively identifying structural differences between these heparins. The binding affinities of these heparins to antithrombin III and thrombin were evaluated by using a surface plasmon resonance competitive binding assay. This study provides the physicochemical and activity characterization necessary for the appropriate design and synthesis of a generic bioengineered heparin.
Assuntos
Físico-Química/métodos , Cromatografia Líquida de Alta Pressão/métodos , Heparina/análise , Espectroscopia de Ressonância Magnética/métodos , Ressonância de Plasmônio de Superfície/métodos , Animais , Antitrombina III/metabolismo , Sequência de Carboidratos , Cromatografia em Gel , Eletroforese em Gel de Poliacrilamida , Glucosamina/análise , Heparina/química , Heparina Liase/metabolismo , Dados de Sequência Molecular , Peso Molecular , Ligação Proteica , Suínos , Trombina/metabolismoRESUMO
OBJECTIVE: To assess the outcome of patients with extra-abdominal desmoid tumor treated with low dose chemotherapy (methotrexate and vinblastine) both for tumor response and treatment related toxicity. METHODS: We retrospectively reviewed the outcome of 12 patients who underwent low dose chemotherapy for extra abdominal desmoid of different locations. The study took place in the McGill University Health Center, Montreal, Canada between 1996 and 2003. We evaluated the patients for their compliance, tumor response, complications of treatment, and impact of treatment on symptoms. There were 7 females and 5 males with a mean age of 46 years. RESULTS: Disease related morbidity included pain in 7 patients, functional limitation in 7 and cosmetic defects in 3. The mean tumor size was 11 cm (3-20 cm). The mean follow-up was 43 months (15-71 months). Chemotherapy was administered weekly. Complications were significant. Only 2 patients did not experience the toxicity. According to Response Evaluation Criteria in Solid Tumors, 6 tumors showed a partial response and 6 remained stable. None showed progression. Of the 7 patients who had painful tumors, 6 achieved significant symptom relief. Function was improved in 3 and restored to normal in 4. Cosmesis was improved in 2 of the 3. At latest follow-up, tumors remained stable in 8, one has markedly regressed and 3 exhibited progression at an average of 54 months. Only one patient required surgery. The only long term side effect was a sensory peripheral neuropathy. CONCLUSION: Low dose chemotherapy was found to be a valuable adjunct to prevent local progression and improve symptoms.
Assuntos
Antineoplásicos/administração & dosagem , Fibroma/tratamento farmacológico , Adulto , Idoso , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-IdadeRESUMO
PURPOSE: The purpose of this study was to evaluate the prognostic effect of early posttransplant lymphocyte recovery in patients with advanced breast cancer receiving high-dose chemotherapy with autologous hematopoietic progenitor cell transplantation. EXPERIMENTAL DESIGN: We analyzed the effect of the absolute lymphocyte count on day +15 posttransplant on freedom from relapse and overall survival in patients with high-risk primary breast cancer or metastatic breast cancer, enrolled between 1990 and 2001 in prospective high-dose chemotherapy trials, using a uniform regimen of cyclophosphamide, cisplatin, and 1,3-bis(2-chloroethyl)-1-nitrosourea. RESULTS: Four hundred and seventy-six patients (264 high-risk primary breast cancer and 212 metastatic breast cancer patients) were evaluated at median follow-up of 8 years (range, 1.5-11 years). The disease-free survival and overall survival rates in the high-risk primary breast cancer group were 67% and 70%, respectively. Patients with metastatic breast cancer patients had 21.8% disease-free survival and 31.5% overall survival rates. Day +15 absolute lymphocyte count correlated with freedom from relapse (P = 0.007) and overall survival (P = 0.04) in the metastatic breast cancer group, but not in the high-risk primary breast cancer group (P = 0.5 and 0.8, respectively). The prognostic effect of absolute lymphocyte count in metastatic breast cancer was restricted to those patients receiving unmanipulated peripheral blood progenitor cells (P = 0.04). In contrast, absolute lymphocyte count had no significant effect in those metastatic breast cancer patients receiving bone marrow or a CD34-selected product. In multivariate analyses, the prognostic effect of day +15 absolute lymphocyte count in metastatic breast cancer was independent of other predictors, such as disease status, pre-high-dose chemotherapy treatment, number of tumor sites, or HER2. CONCLUSIONS: Early lymphocyte recovery is an independent outcome predictor in metastatic breast cancer patients receiving high-dose chemotherapy and an autologous peripheral blood progenitor cell transplant. These observations suggest that immune strategies targeting minimal posttransplant residual disease may prove worthwhile.
Assuntos
Neoplasias da Mama/sangue , Neoplasias da Mama/patologia , Transplante de Células-Tronco Hematopoéticas/métodos , Linfócitos/citologia , Adulto , Idoso , Antígenos CD34/biossíntese , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/mortalidade , Ensaios Clínicos como Assunto , Intervalo Livre de Doença , Feminino , Humanos , Contagem de Linfócitos , Linfócitos/metabolismo , Pessoa de Meia-Idade , Análise Multivariada , Metástase Neoplásica , Prognóstico , Estudos Prospectivos , Fatores de TempoRESUMO
Serum amyloid A (SAA) is an apolipoprotein involved in poorly understood roles in inflammation. Upon trauma, hepatic expression of SAA rises 1000 times the basal levels. In the case of inflammatory diseases like rheumatoid arthritis, there is a risk for deposition of SAA fibrils in various organs leading to Amyloid A (AA) amyloidosis. Although the amyloid deposits in AA amyloidosis accumulate with the glycosaminoglycan (GAG) heparan sulfate, the role GAGs play in the function and pathology of SAA is an enigma. It has been shown that GAG sulfation is a contributing factor in protein fibrillation and for co-aggregating with a plethora of amyloidogenic proteins. Herein, the effects of heparin, heparan sulfate, hyaluronic acid, chondroitin sulfate A, and heparosan on the oligomerization and aggregation properties of pathogenic mouse SAA1.1 were investigated. Delipidated SAA was used to better understand the interactions between SAA and GAGs without the complicating involvement of lipids. The results revealed-to varying degrees-that all GAGs accelerated SAA1.1 aggregation, but had variable effects on its fibrillation. Heparan sulfate, hyaluronic acid, and heparosan did not affect much the fibrillation of SAA1.1. In contrast, chondroitin sulfate A blocked SAA fibril formation and facilitated the formation of spherical aggregates of various sizes. Interestingly, heparin caused formation of spherical SAA1.1 aggregates of various sizes, vast amounts of thin protofibrils, and few long fibrils of various heights. These results suggest that GAGs may have an intrinsic and divergent influence on the aggregation and fibrillation of HDL-free SAA1.1 in vivo, with functional and pathological implications.
Assuntos
Glicosaminoglicanos/farmacologia , Multimerização Proteica/efeitos dos fármacos , Proteína Amiloide A Sérica/química , Sequência de Aminoácidos , Animais , Glicosaminoglicanos/metabolismo , Heparina/metabolismo , Cinética , Camundongos , Modelos Moleculares , Dados de Sequência Molecular , Redobramento de Proteína/efeitos dos fármacos , Estrutura Secundária de Proteína , Proteína Amiloide A Sérica/metabolismoRESUMO
Heparin/heparin sulfate (HS) interacts with a number of proteins thereby playing an essential role in the regulation of many physiological processes. The understanding of heparin/HS-protein interactions at the molecular level is of fundamental importance to biology and will aid in the development of highly specific glycan-based therapeutic agents. The heparin-binding proteins (HBPs) interact with sulfated domains of heparin/HS chains primarily through ionic attraction between negatively charged groups in HS/heparin chains and basic amino acid residues within the protein. Reports in literature have been shown that heparin molecules have a high affinity for a wide range of metal ions. In the present study, we used surface plasmon resonance (SPR) to study the effects of metal ions (under physiological and non-physiological concentrations) on heparin/HS-protein interactions. The results showed that under non-physiological of metal ion concentration, different metal ions showed different effects on heparin binding to fibroblast growth factor-1 (FGF1) and interleakin-7 (IL7). While the effects of individual metal ion at physiological concentrations had little impact on protein binding, the mixed metal ions reduced the FGF1/heparin or IL7/heparin binding affinity, changing its binding profile.
RESUMO
Chondroitin sulfate-E (chondroitin-4, 6-disulfate) was prepared from chondroitin sulfate-A (chondroitin-4 - sulfate) by regioselective sulfonation, performed using trimethylamine sulfur trioxide in formamide under argon. The structure of semi-synthetic chondroitin sulfate-E was analyzed by PAGE, (1)H NMR, (13)C NMR, 2D NMR and disaccharide analysis and compared with natural chondroitin sulfate-E. Both semi-synthetic and natural chondroitin sulfate-E were each biotinylated and immobilized on BIAcore SA biochips and their interactions with fibroblast growth factors displayed very similar binding kinetics and binding affinities. The current semi-synthesis offers an economical approach for the preparation of the rare chondroitin sulfate-E from the readily available chondroitin sulfate-A.
RESUMO
The stability of a formulated heparin was examined during its sterilization by autoclaving. A new method to follow loss in heparin binding to the serine protease inhibitor, antithrombin III, and the serine protease, thrombin, was developed using a surface plasmon resonance competitive binding assay. This loss in binding affinity correlated well with loss in antifactor IIa (thrombin) activity as well as antifactor Xa activity as measured using conventional amidolytic assays. Autoclaving also resulted in a modest breakdown of the heparin backbone as confirmed by a slight reduction in number-averaged and weight-averaged molecular weight and an increase in polydispersity. Although no clear changes were observed by nuclear magnetic resonance spectroscopy, disaccharide composition analysis using high-performance liquid chromatography-electrospray ionization-mass spectrometry suggested that loss of selected sulfo groups had taken place. It is this sulfo group loss that probably accounts for a decrease in the binding of autoclaved heparin to antithrombin III and thrombin as well as the observed decrease in its amidolytic activity.
Assuntos
Anticoagulantes/química , Heparina/química , Temperatura Alta , Esterilização/métodos , Anticoagulantes/farmacologia , Antitrombina III/química , Cromatografia Líquida de Alta Pressão , Estabilidade de Medicamentos , Eletroforese em Gel Bidimensional , Fator Xa/química , Heparina/farmacologia , Humanos , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Ressonância de Plasmônio de Superfície , Trombina/químicaRESUMO
BACKGROUND: It is essential to have the highest level of confidence in axillary staging assessment. Many surgeons and pathologists believe that fewer lymph nodes are present in axillary dissection specimens of women treated by neoadjuvant chemotherapy. Consequently, the purpose of this study was to compare the lymph node counts of axillary dissection specimens from patients having received neoadjuvant chemotherapy with those of patients treated with primary operation. STUDY DESIGN: A retrospective analysis of a prospective database from our institution identified 283 women with invasive breast cancer who underwent level I and II axillary lymph node dissections. Women from the neoadjuvant chemotherapy group (n=107) were compared with those from the primary surgery group (n=176). The total number of lymph nodes harvested was considered as a continuous variable, but also dichotomized into two categories (< 10 and >or=10). Its correlation with the different variables was analyzed. RESULTS: The median number of lymph nodes retrieved in the neoadjuvant chemotherapy group was 10.0 (range 0 to 38) compared with 12.5 (range 0 to 30) in the control group (p=0.002). There were also significantly more patients with fewer than 10 lymph nodes recovered in the neoadjuvant group (45 versus 28%, p=0.007). Logistic regression showed that neoadjuvant chemotherapy was the only factor associated with retrieval of fewer than 10 lymph nodes. CONCLUSIONS: This study suggests that administration of neoadjuvant chemotherapy to breast cancer patients results in a reduced number of lymph nodes retrieved in the axillary dissection specimens.
Assuntos
Antineoplásicos , Neoplasias da Mama/patologia , Excisão de Linfonodo , Linfonodos/patologia , Terapia Neoadjuvante , Axila , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/cirurgia , Quimioterapia Adjuvante , Feminino , Humanos , Modelos Logísticos , Estadiamento de Neoplasias , Estudos RetrospectivosRESUMO
BACKGROUND: Regression of breast tumors in response to neoadjuvant chemotherapy is variable. The goal of breast-conservation operation after neoadjuvant chemotherapy is generally to resect any residual tumor with negative margins. There are limited data about the success of achieving negative resection margins in these patients. The purpose of this study was to compare surgical margin involvement of breast-conservation resection specimens from patients treated initially with operation with those from patients receiving neoadjuvant chemotherapy. METHODS: Between January 2003 and June 2006, 478 breast-conservation operations were performed for invasive breast cancer at our institution. Seventy-six patients received neoadjuvant chemotherapy. Data collected included age, tumor size, nodal status, hormonal receptors and Her-2-neu status, lymphovascular invasion, histologic grade and type, use of guidewire, preoperative chemotherapy regimens, and microscopic evaluation of surgical margins. Univariate analyses and a regression model were used to identify factors associated with margin involvement. RESULTS: No statistical difference was observed for margin involvement between patients treated with neoadjuvant chemotherapy and those treated initially with operation (21% versus 18%; p = 0.52). Variables associated with positive margins in a logistic regression model were carcinoma type (43% of all lobular carcinomas had positive margins versus 16% in ductal carcinomas; p = 0.002) and hormonal receptor status (margin involvement was present in 20% of tumors that exhibited hormonal receptors versus 10% in negative receptors tumors; p = 0.014). CONCLUSIONS: Breast conservation after neoadjuvant systemic therapy yields no higher incidence of positive margins than primary surgical treatment. Special consideration should be accorded to lobular carcinoma, because our findings, consistent with previous studies, demonstrate an association with margin involvement.