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1.
Nutrients ; 16(12)2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38931175

RESUMO

Cancer therapy, from malignant tumor inhibition to cellular eradication treatment, remains a challenge, especially regarding reduced side effects and low energy consumption during treatment. Hence, phytochemicals as cytotoxic sensitizers or photosensitizers deserve special attention. The dark and photo-response of Yemenite 'Etrog' leaf extracts applied to prostate PC3 cancer cells is reported here. An XTT cell viability assay along with light microscope observations revealed pronounced cytotoxic activity of the extract for long exposure times of 72 h upon concentrations of 175 µg/mL and 87.5 µg/mL, while phototoxic effect was obtained even at low concentration of 10.93 µg/mL and a short introduction period of 1.5 h. For the longest time incubation of 72 h and for the highest extract concentration of 175 µg/mL, relative cell survival decreased by up to 60% (below the IC50). In combined phyto-photodynamic therapy, a reduction of 63% compared to unirradiated controls was obtained. The concentration of extract in cells versus the accumulation time was inversely related to fluorescence emission intensity readings. Extracellular ROS production was also shown. Based on an ATR-FTIR analysis of the powdered leaves and their liquid ethanolic extract, biochemical fingerprints of both polar and non-polar phyto-constituents were identified, thereby suggesting their implementation as phyto-medicine and phyto-photomedicine.


Assuntos
Sobrevivência Celular , Fotoquimioterapia , Extratos Vegetais , Folhas de Planta , Neoplasias da Próstata , Humanos , Masculino , Extratos Vegetais/farmacologia , Fotoquimioterapia/métodos , Neoplasias da Próstata/tratamento farmacológico , Folhas de Planta/química , Sobrevivência Celular/efeitos dos fármacos , Fármacos Fotossensibilizantes/farmacologia , Células PC-3 , Espécies Reativas de Oxigênio/metabolismo , Iêmen , Linhagem Celular Tumoral , Antineoplásicos Fitogênicos/farmacologia
2.
Eur J Immunol ; 54(1): e2350627, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37872778

RESUMO

To calibrate a murine model to study premalignant to malignant multiple myeloma, mice were inoculated with different amounts of myeloma cells, and changes in the immune profile were tracked for over 200 days. The model highlights the development of T-cell exhaustion and suppressor before the appearance of clinical symptoms.


Assuntos
Mieloma Múltiplo , Lesões Pré-Cancerosas , Animais , Camundongos , Mieloma Múltiplo/patologia , Imunidade Celular
3.
Biotechnol J ; 19(1): e2300277, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37753941

RESUMO

The rise of biological therapeutics in the global pharmaceuticals market has escalated the demand for quality monoclonal antibodies for healthcare and scientific applications. Reducing costs while enhancing production yields without compromising quality are the main challenges to the growth of this industry today. Over the last two decades non-ionizing radiation has been demonstrated to elicit targeted biological responses in a frequency and dose dependent manner. We hypothesize and design a millimeter wave radiation procedure to enhance the yields of antibody-producing hybridoma cell lines. We demonstrate this method enhances the production of IgA and IgG antibodies from MOPC315.BM and U13.6 cells by a factor of 24.05 ± 3.32 and 1.41 ± 0.03 respectively relative to untreated cells. No treatment associated cytotoxicity was observed in either cell line corroborating physiological viability of irradiated cells. Our results demonstrate proof-of-concept of a novel technique to significantly enhance antibody yields from hybridoma cells which could lead to a reduction in antibody production costs. Further studies will focus on scaling up of this technology and employment of non-contact, tuned electromagnetic stimulation of biological systems for targeted responses.


Assuntos
Anticorpos Monoclonais , Formação de Anticorpos , Hibridomas/metabolismo , Tecnologia , Fenômenos Eletromagnéticos
4.
Sci Rep ; 13(1): 18935, 2023 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-37919384

RESUMO

Cancer is a leading cause of mortality today. Sooner a cancer is detected, the more effective is the treatment. Histopathological diagnosis continues to be the gold standard worldwide for cancer diagnosis, but the methods used are invasive, time-consuming, insensitive, and still rely to some degree on the subjective judgment of pathologists. Recent research demonstrated that Attenuated Total Reflection-Fourier Transform Infrared (ATR-FTIR) spectroscopy can be used to determine the metastatic potential of cancer cells by evaluating their membrane hydration. In the current study, we demonstrate that the conversion of ATR-FTIR spectra using multifractal transformation generates a unique number for each cell line's metastatic potential. Applying this technique to murine and human cancer cells revealed a correlation between the metastatic capacity of cancer cells within the same lineage and higher multifractal value. The multifractal spectrum value was found to be independent of the cell concentration used in the assay and unique to the tested lineage. Healthy cells exhibited a smaller multifractal spectrum value than cancer cells. Further, the technique demonstrated the ability to detect cancer progression by being sensitive to the proportional change between healthy and cancerous cells in the sample. This enables precise determination of cancer metastasis and disease progression independent of cell concentration by comparing the measured spectroscopy derived multifractal spectrum value. This quick and simple technique devoid of observer bias can transform cancer diagnosis to a great extent improving public health prognosis worldwide.


Assuntos
Neoplasias , Humanos , Animais , Camundongos , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Análise de Fourier , Neoplasias/diagnóstico , Proteínas Mutadas de Ataxia Telangiectasia
5.
Cells ; 11(22)2022 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-36429097

RESUMO

Finding synergistic drug combinations is an important area of cancer research. Here, we sought to rationally design synergistic drug combinations with an inhibitor of BTK kinase, ibrutinib, which is used for the treatment of several types of leukemia. We (a) used a pooled shRNA screen to identify genes that protect cells from the drug, (b) identified protective pathways via bioinformatics analysis of these gene sets, and (c) identified drugs that inhibit these pathways. Based on this analysis, we established that inhibitors of proteasome and mTORC1 could synergize with ibrutinib both in vitro and in vivo. We suggest that FDA-approved inhibitors of these pathways could be effectively combined with ibrutinib for the treatment of chronic lymphocytic leukemia (CLL).


Assuntos
Leucemia Linfocítica Crônica de Células B , Humanos , Leucemia Linfocítica Crônica de Células B/metabolismo , Pirimidinas/farmacologia , Pirimidinas/uso terapêutico , Pirazóis/farmacologia , Pirazóis/uso terapêutico , Combinação de Medicamentos , RNA Interferente Pequeno/genética
6.
Pathol Res Pract ; 238: 154040, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36057191

RESUMO

Colorectal cancer (CRC) can been sub-divided, based on the generation of tertiary lymphoid structures (TLS), into CRC with a Crohn's like lymphoid reaction (CLR) representing de novo formation of TLSs or CRC lacking TLSs that show Diffuse Inflammatory infiltration (DII). The association between TLS, early treatment initiation and longer survival highlights the need for deeper patient stratification that could lead to more targeted therapies. We hypothesized that such stratification might be achieved by using digital image analyses. Here we retrospectively analyzed 35 CRC patient samples classified as CLR or DII by digital analysis, focusing on the parameters Fractal dimension, Lacunarity and the textural features Angular second momentum, Correlation, Inverse difference momentum and Entropy. Significant differences in the grades of these parameters between the two patient groups provided preliminary data that additional biophysical information can divide CRC into at least 3 subgroups which encompass CLR and DII. Additional studies are needed to test if this sub-classification aids in the selection of targeted therapy for patients with CRC.

7.
Cells ; 11(15)2022 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-35954169

RESUMO

In recent years, mathematical models have developed into an important tool for cancer research, combining quantitative analysis and natural processes. We have focused on Chronic Lymphocytic Leukemia (CLL), since it is one of the most common adult leukemias, which remains incurable. As the first step toward the mathematical prediction of in vivo drug efficacy, we first found that logistic growth best described the proliferation of fluorescently labeled murine A20 leukemic cells injected in immunocompetent Balb/c mice. Then, we tested the cytotoxic efficacy of Ibrutinib (Ibr) and Cytarabine (Cyt) in A20-bearing mice. The results afforded calculation of the killing rate of the A20 cells as a function of therapy. The experimental data were compared with the simulation model to validate the latter's applicability. On the basis of these results, we developed a new ordinary differential equations (ODEs) model and provided its sensitivity and stability analysis. There was excellent accordance between numerical simulations of the model and results from in vivo experiments. We found that simulations of our model could predict that the combination of Cyt and Ibr would lead to approximately 95% killing of A20 cells. In its current format, the model can be used as a tool for mathematical prediction of in vivo drug efficacy, and could form the basis of software for prediction of personalized chemotherapy.


Assuntos
Antineoplásicos , Leucemia Linfocítica Crônica de Células B , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Simulação por Computador , Citarabina , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Camundongos , Modelos Teóricos
8.
Pharmaceutics ; 14(7)2022 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-35890400

RESUMO

The epidermal growth factor-epidermal growth factor receptor (EGF-EGFR) pathway has become the main focus of selective chemotherapeutic intervention. As a result, two classes of EGFR inhibitors have been clinically approved, namely monoclonal antibodies and small molecule kinase inhibitors. Despite an initial good response rate to these drugs, most patients develop drug resistance. Therefore, new treatment approaches are needed. In this work, we aimed to find a new EGFR-specific, short cyclic peptide, which could be used for targeted drug delivery. Phage display peptide technology and biopanning were applied to three EGFR expressing cells, including cells expressing the EGFRvIII mutation. DNA from the internalized phage was extracted and the peptide inserts were sequenced using next-generation sequencing (NGS). Eleven peptides were selected for further investigation using binding, internalization, and competition assays, and the results were confirmed by confocal microscopy and peptide docking. Among these eleven peptides, seven showed specific and selective binding and internalization into EGFR positive (EGFR+ve) cells, with two of them-P6 and P9-also demonstrating high specificity for non-small cell lung cancer (NSCLC) and glioblastoma cells, respectively. These peptides were chemically conjugated to camptothecin (CPT). The conjugates were more cytotoxic to EGFR+ve cells than free CPT. Our results describe a novel cyclic peptide, which can be used for targeted drug delivery to cells overexpressing the EGFR and EGFRvIII mutation.

9.
J Cell Biochem ; 123(3): 532-542, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34935169

RESUMO

Selenium (Se) is incorporated into the body via the selenocysteine (Sec) biosynthesis pathway, which is critical in the synthesis of selenoproteins, such as glutathione peroxidases and thioredoxin reductases. Selenoproteins, which play a key role in several biological processes, including ferroptosis, drug resistance, endoplasmic reticulum stress, and epigenetic processes, are guided by Se uptake. In this review, we critically analyze the molecular mechanisms of Se metabolism and its potential as a therapeutic target for cancer. Sec insertion sequence binding protein 2 (SECISBP2), which is a positive regulator for the expression of selenoproteins, would be a novel prognostic predictor and an alternate target for cancer. We highlight strategies that attempt to develop a novel Se metabolism-based approach to uncover a new metabolic drug target for cancer therapy. Moreover, we expect extensive clinical use of SECISBP2 as a specific biomarker in cancer therapy in the near future. Of note, scientists face additional challenges in conducting successful research, including investigations on anticancer peptides to target SECISBP2 intracellular protein.


Assuntos
Neoplasias , Selênio , Proteínas de Transporte/metabolismo , Humanos , Redes e Vias Metabólicas , Neoplasias/tratamento farmacológico , Selênio/metabolismo , Selênio/uso terapêutico , Selenoproteínas/química , Selenoproteínas/metabolismo , Tiorredoxina Dissulfeto Redutase/metabolismo
10.
Cancers (Basel) ; 13(16)2021 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-34439244

RESUMO

Current standard frontline therapy for newly diagnosed patients with multiple myeloma (NDMM) involves induction therapy, autologous stem cell transplantation (ASCT), and maintenance therapy. Major efforts are underway to understand the biological and the clinical impacts of each stage of the treatment protocols on overall survival statistics. The most routinely used drugs in the pre-ASCT "induction" regime have different mechanisms of action and are employed either as monotherapies or in various combinations. Aside from their direct effects on cancer cell mortality, these drugs are also known to have varying effects on immune cell functionality. The question remains as to how induction therapy impacts post-ASCT immune reconstitution and anti-tumor immune responses. This review provides an update on the known immune effects of melphalan, dexamethasone, lenalidomide, and bortezomib commonly used in the induction phase of MM therapy. By analyzing the actions of each individual drug on the immune system, we suggest it might be possible to leverage their effects to rationally devise more effective induction regimes. Given the genetic heterogeneity between myeloma patients, it may also be possible to identify subgroups of patients for whom particular induction drug combinations would be more appropriate.

11.
J Nanobiotechnology ; 16(1): 34, 2018 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-29602308

RESUMO

BACKGROUND: Peptide-drug-conjugates (PDCs) are being developed as an effective strategy to specifically deliver cytotoxic drugs to cancer cells. However one of the challenges to their successful application is the relatively low stability of peptides in the blood, liver and kidneys. Since AuNPs seem to have a longer plasma half-life than PDCs, one approach to overcoming this problem would be to conjugate the PDCs to gold nanoparticles (AuNPs), as these have demonstrated favorable physico-chemical and safety properties for drug delivery systems. We set out to test whether PEG coated-AuNPs could provide a suitable platform for the non-covalent loading of pre-formed PDCs and whether this modification would affect the bioavailability of the PDCs and their cytotoxicity toward target cancer cells. METHODS: Peptides specifically internalized by A20 murine lymphoma cells were isolated from a phage library displaying 7mer linear peptides. Peptide specificity was validated by flow cytometry and confocal microscopy. PDCs were synthesized containing a selected peptide (P4) and either chlorambucil (Chlor), melphalan (Melph) or bendamustine (Bend). Gold nanoparticles were sequentially coated with citrate, PEG-6000 and then PDC (PDC-PEG-AuNP). The physico-chemical properties of the coated particles were analyzed by electrophoresis, TEM, UV-VIS and FTIR. Stability of free and PDC-coated AuNP was determined. RESULTS: Biopanning of the phage library resulted in discovery of several novel peptides that internalized into A20 cells. One of these (P4) was used to synthesize PDCs containing either Chlor, Melph or Bend. All three PDCs specifically killed A20 target cells, however they had short half-lives ranging from 10.6 to 15.4 min. When coated to PEG-AuNPs, the half-lives were extended to 21.0-22.3 h. The PDC-PEG-AuNPs retained cytotoxicity towards the target cells. Moreover, whereas pre-incubation for 24 h of free PDCs almost completely abolished their cytotoxic activity, the PDC-PEG-AuNPs were still active even after 72 h pre-incubation. CONCLUSIONS: Peptide-drug-conjugates hold potential for improving the target efficacy of chemotherapeutic drugs, however their short half-lives may limit their application. This hurdle can be overcome by easily conjugating them to gold nanoparticles. This conjugation also opens up the possibility of developing slow release formulations of targeted drug delivery systems containing PDCs.


Assuntos
Sistemas de Liberação de Medicamentos , Ouro/farmacologia , Nanopartículas Metálicas/química , Peptídeos/química , Sequência de Aminoácidos , Animais , Morte Celular/efeitos dos fármacos , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Endocitose/efeitos dos fármacos , Ouro/química , Humanos , Nanopartículas Metálicas/ultraestrutura , Camundongos , Biblioteca de Peptídeos , Preparações Farmacêuticas/metabolismo , Polietilenoglicóis/química , Espectroscopia de Infravermelho com Transformada de Fourier
12.
Appl Spectrosc ; 71(3): 496-506, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27634889

RESUMO

Cerebrospinal fluid (CSF) is a clear and colorless biological fluid which circulates within brain ventricles (cavities), the spinal cord's central canal, the space between the brain and the spinal cord, as well as their protective coverings, the meninges. Cerebrospinal fluid contains different constituents, such as albumin and lactate, whose levels are used clinically as biomarkers of neurodegenerative disorders. In current clinical practice, analysis of CSF content for the diagnosis of central nervous system disorders requires an invasive procedure known as lumbar puncture or spinal tap. With the aim of developing a noninvasive alternative, we report here the spectral behavior of albumin and lactate over a broad wavelength range of 600-2000 nm, after each was added separately at varying normal and abnormal concentration levels to artificial CSF ( aCSF). Spectral measurements were conducted simultaneously by two different spectrometers working at different spectral ranges in transmittance mode. Spectral analysis revealed that albumin and lactate each possesses its own first and second derivative absorbance spectra fingerprint between 1660 and 1810 nm. Distinguishing albumin from lactate by their spectral data enabled the differentiation between aCSF conditions modeling different neurological disorders. Spectral changes of each compound strongly correlated ( R2 > 0.9) with absorbance derivative spectra peaks at specific wavelengths, when analyzed by linear regression with variations in their concentration. These findings suggest the feasibility of CSF biomarker assessment by broadband infrared spectroscopy.


Assuntos
Biomarcadores/líquido cefalorraquidiano , Doenças do Sistema Nervoso/líquido cefalorraquidiano , Doenças do Sistema Nervoso/diagnóstico , Espectrofotometria Infravermelho/métodos , Albuminas/líquido cefalorraquidiano , Humanos , Ácido Láctico/líquido cefalorraquidiano , Punção Espinal
13.
Eur J Med Chem ; 85: 139-46, 2014 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-25084142

RESUMO

Bi-nuclear amino acid platforms loaded with various drugs for conjugation to a peptide carrier were synthesized using simple and convenient orthogonally protective solid-phase organic synthesis (SPOS). Each arm of the platform carries a different anticancer agent linked through the same or different functional group, providing discrete chemo- and bio-release profiles for each drug, and also enabling "switch off/switch on" regulation of drug cytotoxicity by conjugation to the platform and to a cell targeting peptide. The versatility of this approach enables efficient production of drug-loaded platforms and determination of favorable drug combinations/modes of linkage for subsequent conjugation to a carrier moiety for targeted cancer cell therapy. The results presented here potentiate the application of amino acid platforms for targeted drug delivery (TDD).


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Portadores de Fármacos/química , Aminoácidos/química , Animais , Antineoplásicos/toxicidade , Linhagem Celular Tumoral , Portadores de Fármacos/síntese química , Portadores de Fármacos/metabolismo , Estabilidade de Medicamentos , Humanos , Fígado/metabolismo , Camundongos
14.
Anticancer Drugs ; 24(2): 112-9, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23187462

RESUMO

Targeting drugs through small-molecule carriers with a high affinity to receptors on cancer cells can overcome the lack of target cell specificity of most anticancer drugs. These targeted carrier-drug conjugates are also capable of reversing drug resistance in cancer cells. Although many targeted drug delivery approaches are being tested, the linkage of several and different drugs to a single carrier molecule might further enhance their therapeutic efficacy, particularly if the drugs are engineered for variable time release. This report shows that murine B-cell leukemic cells previously resistant to a chemotherapeutic drug can be made sensitive to that drug as long as it is conjugated to a targeting peptide and, in particular, when the conjugate contains multiple copies of the drug. Using a 13mer peptide (VHFFKNIVTPRTP) derived from the myelin basic protein (p-MBP), dendrimer-based peptide conjugates containing one, two, or four molecules of chlorambucil were synthesized. Although murine hybridomas expressing antibodies to either p-MBP (MBP cells) or a nonrelevant antigen (BCL-1 cells) were both resistant to free chlorambucil, exposure of the cells to the p-MBP-chlorambucil conjugate completely reversed the drug resistance in MBP, but not BCL-1 cells or normal spleen cells. Moreover, at equivalent drug doses, there was significant enhancement in the cytotoxic activity of multidrug versus single-drug copy conjugates. On the basis of these results, the use of multifunctional dendrone linkers bearing several covalently bound cytotoxic agents allows the development of more effective targeted drug systems and enhances the efficacy of currently approved drugs for B-cell leukemia.


Assuntos
Clorambucila/farmacologia , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Peptídeos/farmacologia , Animais , Linhagem Celular Tumoral , Clorambucila/química , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/métodos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Feminino , Leucemia Linfocítica Crônica de Células B/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Peptídeos/química
15.
J Hematol Oncol ; 5: 70, 2012 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-23140144

RESUMO

Therapeutic monoclonal antibody (TMA) based therapies for cancer have advanced significantly over the past two decades both in their molecular sophistication and clinical efficacy. Initial development efforts focused mainly on humanizing the antibody protein to overcome problems of immunogenicity and on expanding of the target antigen repertoire. In parallel to naked TMAs, antibody-drug conjugates (ADCs) have been developed for targeted delivery of potent anti-cancer drugs with the aim of bypassing the morbidity common to conventional chemotherapy. This paper first presents a review of TMAs and ADCs approved for clinical use by the FDA and those in development, focusing on hematological malignancies. Despite advances in these areas, both TMAs and ADCs still carry limitations and we highlight the more important ones including cancer cell specificity, conjugation chemistry, tumor penetration, product heterogeneity and manufacturing issues. In view of the recognized importance of targeted drug delivery strategies for cancer therapy, we discuss the advantages of alternative drug carriers and where these should be applied, focusing on peptide-drug conjugates (PDCs), particularly those discovered through combinatorial peptide libraries. By defining the advantages and disadvantages of naked TMAs, ADCs and PDCs it should be possible to develop a more rational approach to the application of targeted drug delivery strategies in different situations and ultimately, to a broader basket of more effective therapies for cancer patients.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Neoplasias/tratamento farmacológico , Animais , Anticorpos Monoclonais/administração & dosagem , Humanos , Neoplasias/metabolismo , Neoplasias/terapia
16.
Photochem Photobiol ; 86(6): 1350-5, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20880227

RESUMO

The increasing resistance of bacteria to antibiotics is a serious problem, caused in part by excessive and improper use of these drugs. One alternative to traditional antibiotic therapy is photodynamic antimicrobial chemotherapy (PACT) which is based on the use of a photosensitizer (PS), activated by illumination with visible light. The poor penetration of visible light through the skin limits the application of PACT to the treatment of skin infections or the use of invasive procedures. To overcome this problem we report the exploitation of light emitted as a result of the chemiluminescent reaction of luminol to excite the PS and we call this process chemiluminescent photodynamic antimicrobial therapy (CPAT). We studied the effect of free and liposome-encapsulated PS (methylene blue or toluidine blue) on bacteria under excitation by either white external light or chemiluminescence emitted by free or liposome-enclosed luminol. PACT showed slightly better performance that CPAT for free and encapsulated PS for both types of bacteria. CPAT resulted in a three log suppression of Staphylococcus aureus and two log suppression of Escherichia coli growth. The use of CPAT may prove to be a novel and more effective form of antimicrobial therapy, particularly for internal infections not easily accessible to traditional PACT.


Assuntos
Anti-Infecciosos/administração & dosagem , Bactérias/efeitos dos fármacos , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/administração & dosagem , Bactérias/patogenicidade , Bactérias/efeitos da radiação , Infecções Bacterianas/tratamento farmacológico , Escherichia coli/efeitos dos fármacos , Humanos , Técnicas In Vitro , Lipossomos , Luminescência , Azul de Metileno/administração & dosagem , Staphylococcus aureus/efeitos dos fármacos , Cloreto de Tolônio/administração & dosagem
17.
J Biol Chem ; 282(39): 28301-28308, 2007 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-17626007

RESUMO

Multiple myeloma is currently an incurable cancer of plasma B cells often characterized by overproduction of abnormally high quantities of a patient-specific, clonotypic immunoglobulin "M-protein." The M-protein is expressed on the cell membrane and secreted into the blood. We previously showed that ligand-toxin conjugates (LTC) incorporating the ribosome-inactivating Ricin-A toxin were very effective in specific cytolysis of the anti-ligand antibody-bearing target cells used as models for multiple myeloma. Here, we report on the incorporation of the membrane-disruptive Cyt1Aa toxin from Bacillus thuringiensis subsp. israelensis into LTCs targeted to murine myeloma cells. Proteolytically activated Cyt1Aa was conjugated chemically or genetically through either its amino or carboxyl termini to the major peptidic epitope VHFFKNIVTPRTP (p87-99) of the myelin basic protein. The recombinant fusion-encoding genes were cloned and expressed in acrystalliferous B. thuringiensis subsp. israelensis through the shuttle vector pHT315. Both chemically conjugated and genetically fused LTCs were toxic to anti-myelin basic protein-expressing murine hybridoma cells, but the recombinant conjugates were more active. LTCs comprising the Cyt1Aa toxin might be useful anticancer agents. As a membrane-acting toxin, Cyt1Aa is not likely to induce development of resistant cell lines.


Assuntos
Antineoplásicos/imunologia , Proteínas de Bactérias/imunologia , Toxinas Bacterianas/imunologia , Endotoxinas/imunologia , Proteínas Hemolisinas/imunologia , Imunotoxinas/imunologia , Mieloma Múltiplo/imunologia , Proteína Básica da Mielina/imunologia , Proteínas do Mieloma/imunologia , Peptídeos/imunologia , Proteínas Recombinantes de Fusão/imunologia , Animais , Anticorpos Monoclonais/imunologia , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Bacillus thuringiensis/química , Bacillus thuringiensis/genética , Bacillus thuringiensis/imunologia , Toxinas de Bacillus thuringiensis , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/uso terapêutico , Toxinas Bacterianas/química , Toxinas Bacterianas/genética , Toxinas Bacterianas/uso terapêutico , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/imunologia , Endotoxinas/química , Endotoxinas/genética , Endotoxinas/uso terapêutico , Expressão Gênica , Proteínas Hemolisinas/química , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/uso terapêutico , Hibridomas , Imunotoxinas/genética , Imunotoxinas/uso terapêutico , Ligantes , Camundongos , Modelos Biológicos , Mieloma Múltiplo/tratamento farmacológico , Proteína Básica da Mielina/química , Proteína Básica da Mielina/genética , Proteína Básica da Mielina/uso terapêutico , Proteínas do Mieloma/antagonistas & inibidores , Proteínas do Mieloma/genética , Peptídeos/química , Peptídeos/genética , Peptídeos/uso terapêutico , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/uso terapêutico , Ricina/química , Ricina/genética , Ricina/imunologia , Ricina/uso terapêutico
18.
Comput Biol Med ; 35(3): 229-45, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15582630

RESUMO

The paper describes a hierarchical design approach to an immunoassay. A morphology for an immunoassay technology is considered as a basis to generate system versions. A 5-stage technology is analyzed. The problem is: Find the best composite version for each stage while taking into account requirements (criteria) at each stage and compatibility between selected design alternatives at different stages. Hierarchical solving procedure consists of two parts: (a) multicriteria ranking of alternative versions at each stage (e.g., selection of Pareto-effective local decisions), (b) composition of the selected versions into a parallel-series composite system (technology). A realistic numerical example illustrates the approach.


Assuntos
Inteligência Artificial , Imunoensaio/métodos , Humanos
19.
Leuk Lymphoma ; 44(4): 681-9, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12769346

RESUMO

Many types of leukemia including multiple myeloma remain essentially incurable despite recent developments in immuno- and chemotherapy. The effectiveness of these therapies might be greatly enhanced by targeting cell surface proteins unique to the malignant clone, which for leukemias of the B cell lineage means clonotypic surface immunoglobulin (sIg). As this immunoglobulin (Ig) is necessarily epitope specific, we are developing ligand-toxin conjugates (LTCs) as a strategy for delivering toxins and other drugs to clonotypic tumor cells. Here we report in vitro studies that illustrate the effectiveness of this approach. LTC comprising the DNP hapten conjugated to ricin A toxin (DNP-RTA) were shown to specifically and effectively kill anti-DNP secreting murine hybridoma (U7.6) cells but not other hybridoma cells (1B12), a murine erythroleukemia cell line (Friend's Leukemia or) normal mouse spleen cells. In addition to direct toxicity, LTC treatment negatively affected the growth characteristics of the few surviving cells as reflected in decreased growth index and an increase in growth inhibition over 72 h post treatment. Interestingly, U7.6 cells that survived one or two LD90 dose(s) of LTC showed no alteration in their dose response to a subsequent attack of LTC indicating that this treatment strategy may not induce drug resistance. These data suggest that LTC therapy may be a new and effective strategy for specific destruction of tumor cells such as myeloma plasma cells and could be extended to other tumors where clonotypic receptors can be identified.


Assuntos
Linfócitos B/citologia , Hibridomas/metabolismo , Leucemia/tratamento farmacológico , Animais , Antígenos/metabolismo , Divisão Celular , Linhagem Celular , Linhagem da Célula , Relação Dose-Resposta a Droga , Resistencia a Medicamentos Antineoplásicos , Epitopos , Citometria de Fluxo , Humanos , Imunoglobulinas/metabolismo , Ligantes , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Microscopia de Fluorescência , Especificidade da Espécie , Baço/citologia , Fatores de Tempo , Toxinas Biológicas/metabolismo
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