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1.
Respirology ; 22(4): 671-677, 2017 05.
Article in English | MEDLINE | ID: mdl-27899011

ABSTRACT

BACKGROUND AND OBJECTIVE: Determination of asthma phenotypes, particularly inflammatory phenotypes, helps guide treatment and management of this heterogeneous disease. Induced sputum cytology has been the gold standard for determination of inflammatory phenotypes, but sputum induction is fairly invasive and technically challenging. Blood and nasal lavage cytology have been suggested as substitutes, but have not been fully verified. The aim of this study is to determine the accuracy of blood and nasal lavage cytometry as indicators of inflammatory phenotypes in asthma. METHODS: Clinical evaluation, Asthma Control Questionnaire (ACQ) and spirometry were performed for 121 adult asthma patients, and blood, nasal lavage and induced sputum samples were taken. Eosinophils and neutrophils were counted in three samples from each subject. Inflammatory phenotypes (eosinophilic, neutrophilic, mixed and paucicellular) and cells counts were analysed using Venn diagram and receiver operating characteristic (ROC) curve, respectively. RESULTS: ACQ score, spirometry and bronchodilator response did not differ among subjects with different inflammatory phenotypes. Inflammatory phenotypes defined by nasal lavage cytometry were in better concordance than those defined by blood cell counts with phenotypes determined by sputum cytology, and were significantly correlated with sputum phenotypes. For eosinophilia, nasal lavage cytology showed better accuracy than blood cytology (area under the curve (AUC): 0.89 vs 0.65). For all phenotypes, sensitivity and positive and negative predictive power were higher for nasal lavage cytometry than for blood. Blood cell counts gave a high level of false positives for all inflammatory phenotypes. CONCLUSION: We recommend nasal lavage cytology over blood cell count as a substitute for sputum cytology to identify inflammatory phenotypes in asthma.


Subject(s)
Asthma/diagnosis , Nasal Lavage Fluid/cytology , Nasal Lavage/methods , Sputum/cytology , Asthma/metabolism , Blood Cell Count , Cross-Sectional Studies , Eosinophils/pathology , Female , Humans , Male , Middle Aged , Neutrophils/pathology , Phenotype
2.
FEBS Open Bio ; 6(9): 885-901, 2016 09.
Article in English | MEDLINE | ID: mdl-27642552

ABSTRACT

Antibody-derived peptides modulate functions of the immune system and are a source of anti-infective and antitumor substances. Recent studies have shown that they comprise amino acid sequences of immunoglobulin complementarity-determining regions, but also fragments of constant regions. VH CDR3 of murine mAb AC-1001 displays antimetastatic activities using B16F10-Nex2 murine melanoma cells in a syngeneic model. The peptide was cytotoxic in vitro in murine and human melanoma cells inducing reactive oxygen species (ROS) and apoptosis by the intrinsic pathway. Signs of autophagy were also suggested by the increased expression of LC3/LC3II and Beclin 1 and by ultrastructural evidence. AC-1001 H3 bound to both G- and F-actin and inhibited tumor cell migration. These results are important evidence of the antitumor activity of Ig CDR-derived peptides.

3.
Peptides ; 85: 1-15, 2016 11.
Article in English | MEDLINE | ID: mdl-27575453

ABSTRACT

The present work aims at investigating the mechanism of action of the Rb9 peptide, which contains the VHCDR 3 sequence of anti-sodium-dependent phosphate transport protein 2B (NaPi2B) monoclonal antibody RebMab200 and displayed antitumor properties. Short peptides corresponding to the hypervariable complementarity-determining regions (CDRs) of immunoglobulins have been associated with antimicrobial, antiviral, immunomodulatory and antitumor activities regardless of the specificity of the antibody. We have shown that the CDR derived peptide Rb9 induced substrate hyperadherence, inhibition of cell migration and matrix invasion in melanoma and other tumor cell lines. Rb9 also inhibited metastasis of murine melanoma in a syngeneic mouse model. We found that Rb9 binds to and interferes with Hsp90 chaperone activity causing attenuation of FAK-Src signaling and downregulation of active Rac1 in B16F10-Nex2 melanoma cells. The peptide also bound to an adhesion G-protein coupled receptor, triggering a concentration-dependent synthesis of cAMP and activation of PKA and VASP signaling as well as IP-3 dependent Ca2+ release. Hsp90 is highly expressed on the cell surface of melanoma cells, and synthetic agents that target Hsp90 are promising cancer therapeutic drugs. Based on their remarkable antitumor effects, the CDR-H3-derived peptides from RebMab200, and particularly the highly soluble and stable Rb9, are novel candidates to be further studied as potential antitumor drugs, selectively acting on cancer cell motility and invasion.


Subject(s)
Complementarity Determining Regions/genetics , HSP90 Heat-Shock Proteins/genetics , Melanoma, Experimental/drug therapy , Peptides/genetics , Animals , Antibodies, Monoclonal/genetics , Antibodies, Monoclonal/immunology , Cell Adhesion/genetics , Cell Adhesion/immunology , Cell Movement/genetics , Complementarity Determining Regions/immunology , HSP90 Heat-Shock Proteins/immunology , Immunoglobulin Variable Region/genetics , Immunoglobulin Variable Region/immunology , Melanoma, Experimental/genetics , Melanoma, Experimental/immunology , Mice , Neoplasm Invasiveness/genetics , Neuropeptides/genetics , Peptides/administration & dosage , Peptides/immunology , Receptors, G-Protein-Coupled/genetics , Sodium-Phosphate Cotransporter Proteins, Type IIb/genetics , Sodium-Phosphate Cotransporter Proteins, Type IIb/immunology , rac1 GTP-Binding Protein/genetics
4.
Biochem Biophys Res Commun ; 467(4): 928-34, 2015 Nov 27.
Article in English | MEDLINE | ID: mdl-26471302

ABSTRACT

Natural monoterpenes were isolated from the essential oil of Piper cernuum Vell. (Piperaceae) leaves. The crude oil and the individual monoterpenes were tested for cytotoxicity in human tumor cell lineages and B16F10-Nex2 murine melanoma cells. In the present work we demonstrate the activity of camphene against different cancer cells, with its mechanism of action being investigated in vitro and in vivo in murine melanoma. Camphene induced apoptosis by the intrinsic pathway in melanoma cells mainly by causing endoplasmic reticulum (ER) stress, with release of Ca(2+) together with HmgB1 and calreticulin, loss of mitochondrial membrane potential and up regulation of caspase-3 activity. Importantly, camphene exerted antitumor activity in vivo by inhibiting subcutaneous tumor growth of highly aggressive melanoma cells in a syngeneic model, suggesting a promising role of this compound in cancer therapy.


Subject(s)
Antineoplastic Agents, Phytogenic/therapeutic use , Apoptosis/drug effects , Melanoma, Experimental/drug therapy , Piper/chemistry , Terpenes/therapeutic use , Animals , Antineoplastic Agents, Phytogenic/pharmacology , Bicyclic Monoterpenes , Calcium/metabolism , Calreticulin/metabolism , Cell Line, Tumor , Endoplasmic Reticulum/drug effects , Humans , Melanoma, Experimental/pathology , Membrane Potential, Mitochondrial/drug effects , Mice , Terpenes/pharmacology
5.
Molecules ; 20(7): 12757-68, 2015 Jul 15.
Article in English | MEDLINE | ID: mdl-26184150

ABSTRACT

Nectandra megapotamica (Spreng.) Mez. (Lauraceae) is a well-known Brazilian medicinal plant that has been used in folk medicine to treat several diseases. In continuation of our ongoing efforts to discover new bioactive natural products from the Brazilian flora, this study describes the identification of cytotoxic compounds from the MeOH extract of N. megapotamica (Lauraceae) leaves using bioactivity-guided fractionation. This approach resulted in the isolation and characterization of eight tetrahydrofuran neolignans: calopeptin (1), machilin-G (2), machilin-I (3), aristolignin (4), nectandrin A (5), veraguensin (6), ganschisandrin (7), and galgravin (8). Different assays were conducted to evaluate their cytotoxic activities and to determine the possible mechanism(s) related to the activity displayed against human leukemia cells. The most active compounds 4, 5 and 8 gave IC50 values of 14.2 ± 0.7, 16.9 ± 0.8 and 16.5 ± 0.8 µg/mL, respectively, against human leukemia (HL-60) tumor cells. Moreover, these compounds induced specific apoptotic hallmarks, such as plasma membrane bleb formation, nuclear DNA condensation, specific chromatin fragmentation, phosphatidyl-serine exposure on the external leaflet of the plasma membrane, cleavage of PARP as well as mitochondrial damage, which as a whole could be related to the intrinsic apoptotic pathway.


Subject(s)
Antineoplastic Agents, Phytogenic/pharmacology , Cytotoxins/pharmacology , Lauraceae/chemistry , Lignans/pharmacology , Plant Leaves/chemistry , Animals , Antineoplastic Agents, Phytogenic/chemistry , Antineoplastic Agents, Phytogenic/isolation & purification , Apoptosis/drug effects , Brazil , Cell Membrane/drug effects , Cell Membrane/ultrastructure , Cell Survival/drug effects , Cytotoxins/chemistry , Cytotoxins/isolation & purification , DNA Fragmentation/drug effects , HL-60 Cells , HeLa Cells , Humans , Inhibitory Concentration 50 , Lignans/chemistry , Lignans/isolation & purification , MCF-7 Cells , Melanoma, Experimental , Mice , Organ Specificity , Phosphatidylserines/chemistry , Phosphatidylserines/metabolism , Plant Extracts/chemistry , Plants, Medicinal , Poly(ADP-ribose) Polymerases/chemistry , Poly(ADP-ribose) Polymerases/metabolism , Proteolysis , Structure-Activity Relationship
6.
Nat Prod Commun ; 10(2): 285-8, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25920262

ABSTRACT

Fractionation of the MeOH extract from leaves of Piper cernuum Vell. (Piperaceae) afforded six phenylpropanoid derivatives: 3',4'-dimethoxydihydrocinnamic acid (1), piplaroxide (2), methyl 4'-hydroxy-3',5'-dimethoxy cinnamate (3), 3',4',5'-trimethoxydihydrocinnamic acid (3), dihydropiplartine (5), and piplartine (6). The structures of isolated metabolites were characterized by NMR and MS spectral data analysis. The chemical composition of essential oil from the leaves was determined using GC/LREIMS followed by the determination of Kovats indexes. This procedure allowed the identification of nineteen terpenoids, with ß-elemene (7), bicyclogermacrene (8), germacrene D (9), and (E)-caryophyllene (10) as the main compounds. Compounds 1 and 3-6 displayed no in vitro cytotoxicity against cancer cell lineages B16F10-Nex2, U87, HeLa, HL-60, HCT, and A2058 while 2 showed moderate activity against B16F10-Nex2 and HL-60 lines. Otherwise, compounds 7-10 displayed high cytotoxic activity. Evaluation against non-tumorigenic HFF cells indicated a reduced selectivity of compounds 7-10 to tumoral cells. No antileishmanial activity on macrophages infected with L. (L.) amnazonensis was found for the crude MeOH extract and compounds 1-6. The crude essential oil and compounds 7-10 reduced parasitism and eliminated the majority of infected and non-infected cells at 50 µg/mL.


Subject(s)
Antineoplastic Agents, Phytogenic/pharmacology , Antiprotozoal Agents/pharmacology , Oils, Volatile/pharmacology , Piper/chemistry , Plant Extracts/pharmacology , Plant Oils/pharmacology , Animals , Antineoplastic Agents, Phytogenic/chemistry , Antiprotozoal Agents/chemistry , Cell Line, Tumor , Humans , Leishmania/drug effects , Macrophages/parasitology , Mice , Molecular Structure , Oils, Volatile/chemistry , Plant Extracts/chemistry , Plant Leaves/chemistry , Plant Oils/chemistry
7.
Peptides ; 68: 113-9, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25305549

ABSTRACT

Mastoparan is an α-helical and amphipathic tetradecapeptide obtained from the venom of the wasp Vespula lewisii. This peptide exhibits a wide variety of biological effects, including antimicrobial activity, increased histamine release from mast cells, induction of a potent mitochondrial permeability transition and tumor cell cytotoxicity. Here, the effects of mastoparan in malignant melanoma were studied using the murine model of B16F10-Nex2 cells. In vitro, mastoparan caused melanoma cell death by the mitochondrial apoptosis pathway, as evidenced by the Annexin V-FITC/PI assay, loss of mitochondrial membrane potential (ΔΨm), generation of reactive oxygen species, DNA degradation and cell death signaling. Most importantly, mastoparan reduced the growth of subcutaneous melanoma in syngeneic mice and increased their survival. The present results show that mastoparan induced caspase-dependent apoptosis in melanoma cells through the intrinsic mitochondrial pathway protecting the mice against tumor development.


Subject(s)
Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Melanoma, Experimental/drug therapy , Peptides/pharmacology , Wasp Venoms/pharmacology , Animals , Cell Line, Tumor , Cell Shape/drug effects , Drug Screening Assays, Antitumor , Intercellular Signaling Peptides and Proteins , Male , Melanoma, Experimental/pathology , Membrane Potential, Mitochondrial/drug effects , Mice, Inbred C57BL , Mitochondria/drug effects , Neoplasm Transplantation , Oxidative Stress , Tumor Burden/drug effects
8.
J Immunol Methods ; 414: 11-9, 2014 Dec 01.
Article in English | MEDLINE | ID: mdl-25205401

ABSTRACT

On searching for melanoma transcription factors in a project focusing on internal antitumor peptide sequences from transcription factors, we found that a highly immunogenic component emerged upon using a subtraction tolerization method of immunization. While several conventional immunization procedures using whole melanoma cells induced a plethora of low affinity antibodies of various specificities, the subtraction tolerization method efficiently elicited mono-specific antibodies that recognized Wilms' tumor protein 1 (WT1), which is known as an important marker in melanoma prognosis and treatment. For the tolerization step, pre-immunization of Balb/c mice with a membrane-rich preparation of glioblastoma U87 cells was used. The subsequent immunizations with SK-MEL-28 melanoma cells elicited antibodies strongly reacting with 50 and 55 kDa proteins, identified as WT1. Remarkably, this was the only component strongly reactive with these antibodies in a melanoma cell lysate. WT1 was then chosen as a target for selecting internally bioactive peptides. A hydrophilic Trojan peptide containing most of the zinc finger-2 domain of WT1 was synthesized and shown to inhibit SK-MEL-28 melanoma growth in vitro. The peptide WT1-pTj was also protective in vivo in a metastatic melanoma model and peptide-stimulated syngeneic dendritic cells reproduced the anti-melanoma effect of the unprotected peptide. Identification of antitumor peptides derived from major transcription factors represents a new tool to be explored in cancer research aiming at new therapeutic drugs.


Subject(s)
Antibodies, Neoplasm/immunology , Cancer Vaccines/immunology , Melanoma, Experimental/immunology , WT1 Proteins/immunology , Animals , Biomarkers, Tumor/immunology , Cancer Vaccines/therapeutic use , Cell Line, Tumor , Cell Proliferation , Dendritic Cells/immunology , Female , Humans , Immune Tolerance/immunology , Immunization/methods , Male , Melanoma, Experimental/genetics , Melanoma, Experimental/therapy , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Microscopy, Confocal , Peptides/immunology , Peptides/therapeutic use , WT1 Proteins/therapeutic use
9.
Pharmacogn Mag ; 10(Suppl 2): S363-76, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24991116

ABSTRACT

BACKGROUND: Pyrostegia venusta (Ker. Gawl.) Miers (Bignoniacea) is a medicinal plant from the Brazilian Cerrado used to treat leucoderma and common diseases of the respiratory system. OBJECTIVE: To investigate the antitumor activity of P.venusta extracts against melanoma. MATERIALS AND METHODS: The cytotoxic activity and tumor induced cell death of heptane extract (HE) from P. venusta flowers was evaluated against murine melanoma B16F10-Nex2 cells in vitro and in a syngeneic model in vivo. RESULTS: We found that HE induced apoptosis in melanoma cells by disruption of the mitochondrial membrane potential, induction of reactive oxygen species and late apoptosis evidenced by plasma membrane blebbing, cell shrinkage, chromatin condensation and DNA fragmentation, exposure of phosphatidylserine on the cell surface and activation of caspase-2,-3,-8,-9. HE was also protective against singeneyc subcutaneous melanoma HE compounds were also able to induce cell cycle arrest at G2/M phases on tumor cells. On fractionation of HE in silica gel we isolated a cytotoxic fraction that contained a mixture of saturated hydrocarbons identified by (1)H NMR and GC-MS analyses. Predominant species were octacosane (C28H58-36%) and triacontane (C30H62-13%), which individually showed significant cytotoxic activity against murine melanoma B16F10-Nex2 cells in vitro and a very promising antitumor protection against subcutaneous melanoma in vivo. CONCLUSION: The results suggest that the components of the heptane extract, mainly octasane and triacontane, which showed antitumor properties in experimental melanoma upon regional administration, might also be therapeutic in human cancer, such as in the mostly epidermal and slowly invasive melanomas, such as acral lentiginous melanoma, as an adjuvant treatment to surgical excision.

10.
PLoS One ; 7(6): e38698, 2012.
Article in English | MEDLINE | ID: mdl-22701695

ABSTRACT

BACKGROUND: Malignant melanoma is a deadly type of metastatic skin cancer with increased incidence over the past 30 years. Despite the advanced knowledge on the biology, immunobiology and molecular genetics of melanoma, the alternatives of treatment are limited with poor prognosis. On clinical trials, natural products and among them redox-active quinones have been tested in the attempt to control the growth of cancer cells. Recently, we isolated jacaranone from Pentacalia desiderabilis, a benzoquinone derivative that showed a broad antitumor activity and protective anti-melanoma effect in a syngeneic model. The purified substance is active at micromolar concentrations, is not hemolytic, and is not toxic in naïve mice. METHODOLOGY/PRINCIPAL FINDINGS: The jacaranone antitumor activity was shown against several human cancer cell lines in vitro. Moreover, the induction of apoptosis in murine melanoma cells and jacaranone antitumor activity in vivo, in a melanoma experimental model, were also shown. Jacaranone renders antiproliferative and proapoptotic responses in tumor cells, by acting on Akt and p38 MAPK signaling pathways through generation of reactive oxygen species (ROS). The free radical scavenger N-acetyl-cysteine (NAC) was able to completely suppress cell death induced by jacaranone as it blocked Akt downregulation, p38 MAPK activation as well as upregulation of proapoptotic Bax. Notably, treatment of melanoma growing subcutaneously in mice with jacaranone significantly extended the mean survival times in a dose-dependent manner. CONCLUSIONS/SIGNIFICANCE: The results provide evidence for the mechanisms of action of jacaranone and emphasize the potential use of this quinone for the treatment of melanoma.


Subject(s)
Antineoplastic Agents/pharmacology , Asteraceae/chemistry , Benzoquinones/pharmacology , Melanoma/drug therapy , Phytotherapy/methods , Plant Extracts/pharmacology , Signal Transduction/drug effects , Acetylcysteine , Animals , Annexin A5 , Antineoplastic Agents/analysis , Antineoplastic Agents/therapeutic use , Apoptosis/drug effects , Benzoquinones/analysis , Benzoquinones/therapeutic use , Blotting, Western , Cell Line, Tumor , Chromatin/metabolism , Colorimetry , Down-Regulation , Humans , In Situ Nick-End Labeling , In Vitro Techniques , Male , Membrane Potential, Mitochondrial , Mice , Mice, Inbred C57BL , Microscopy, Electron, Transmission , Nuclear Magnetic Resonance, Biomolecular , Propidium , Proto-Oncogene Proteins c-akt/metabolism , Reactive Oxygen Species/metabolism , Superoxides , p38 Mitogen-Activated Protein Kinases/metabolism
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