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1.
J Maxillofac Oral Surg ; : 1-9, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36337300

RESUMO

Aim: To perform site-based comparative analysis for samples collected from the nasal region and oral cavity subjected to microscopic detection of fungal hyphae in KOH mount in a group of patients with rhinomaxillary mucormycosis. Methodology: Forty patients fulfilled eligibility criteria. The diagnostic outcome of detection of fungal hyphae from the KOH samples obtained was the primary endpoint of the study. Based on this, the samples were grouped into three groups viz-oral, nasal and both. The secondary outcome was to check if there was any diagnostic delay in these three groups of patients. Results: The mean number of days for delayed diagnosis for oral site involvement was 56.33 ± 37.53, for nasal involvement was 32.86 ± 19.53 and for both oral and nasal involvement was 22.00 ± 12.94. This difference was statistically significant at p = 0.03. The mean delay in diagnosis was significantly less when both oral and nasal regions are involved as compared to the only oral region involved at P = 0.01. Conclusion: To avoid the chance of delayed diagnosis or false-negative results, it is best to collect samples from both nasal tissues and the most representative site in the dentoalveolar segment depending on the extensiveness of the disease.

2.
BMJ Case Rep ; 15(10)2022 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-36192029

RESUMO

Leprosy was eliminated globally in 2000, but it continues to be endemic in developing countries like India, Brazil and Indonesia, with a prevalence of 0.57/10 000 persons in India (2020). At the end of the year 2020, the prevalence was 129 389, and oral manifestation of the leprosy is luncommon. We hereby report a case of a female patient in her late 30s who presented with palatal perforation. Following a thorough history taking and full body clinical examination, we arrived at a diagnosis of leprosy, and prompt treatment was initiated. Knowledge of cases like this becomes important as the oral lesion is said to form an essential source of leprosy dissemination in the community, and awareness about them becomes crucial, demanding immediate attention.


Assuntos
Hanseníase Dimorfa , Hanseníase Virchowiana , Hanseníase Multibacilar , Hanseníase , Feminino , Humanos , Índia/epidemiologia , Hanseníase/diagnóstico , Hanseníase Dimorfa/epidemiologia , Hanseníase Dimorfa/patologia , Hanseníase Virchowiana/complicações , Hanseníase Virchowiana/diagnóstico , Hanseníase Virchowiana/tratamento farmacológico , Prevalência
3.
Nat Cell Biol ; 16(12): 1192-201, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25419851

RESUMO

Dynactin is the longest known cytoplasmic dynein regulator, with roles in dynein recruitment to subcellular cargo and in stimulating processive dynein movement. The latter function was thought to involve the N-terminal microtubule-binding region of the major dynactin polypeptide p150(Glued), although recent results disputed this. To understand how dynactin regulates dynein we generated recombinant fragments of the N-terminal half of p150(Glued). We find that the dynein-binding coiled-coil α-helical domain CC1B is sufficient to stimulate dynein processivity, which it accomplishes by increasing average dynein step size and forward-step frequency, while decreasing lateral stepping and microtubule detachment. In contrast, the immediate upstream coiled-coil domain, CC1A, activates a surprising diffusive dynein state. CC1A interacts physically with CC1B and interferes with its effect on dynein processivity. We also identify a role for the N-terminal portion of p150(Glued) in coordinating these activities. Our results reveal an unexpected form of long-range allosteric control of dynein motor function by internal p150(Glued) sequences, and evidence for p150(Glued) autoregulation.


Assuntos
Dineínas/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Fragmentos de Peptídeos/química , Sequência de Aminoácidos , Animais , Sítios de Ligação , Complexo Dinactina , Proteínas Associadas aos Microtúbulos/genética , Microtúbulos/metabolismo , Fragmentos de Peptídeos/análise , Fragmentos de Peptídeos/genética , Ligação Proteica , Estrutura Terciária de Proteína , Transporte Proteico , Ratos , Proteínas Recombinantes/genética , Células Sf9 , Spodoptera
4.
Elife ; 1: e00003, 2012 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-23150794

RESUMO

We previously discovered histones bound to cytosolic lipid droplets (LDs); here we show that this forms a cellular antibacterial defense system. Sequestered on droplets under normal conditions, in the presence of bacterial lipopolysaccharide (LPS) or lipoteichoic acid (LTA), histones are released from the droplets and kill bacteria efficiently in vitro. Droplet-bound histones also function in vivo: when injected into Drosophila embryos lacking droplet-bound histones, bacteria grow rapidly. In contrast, bacteria injected into embryos with droplet-bound histones die. Embryos with droplet-bound histones displayed more than a fourfold survival advantage when challenged with four different bacterial species. Our data suggests that this intracellular antibacterial defense system may function in adult flies, and also potentially in mice.DOI:http://dx.doi.org/10.7554/eLife.00003.001.


Assuntos
Drosophila melanogaster/imunologia , Embrião não Mamífero/imunologia , Histonas/imunologia , Gotículas Lipídicas/imunologia , Fígado/imunologia , Animais , Bacillus subtilis/efeitos dos fármacos , Bacillus subtilis/crescimento & desenvolvimento , Drosophila melanogaster/metabolismo , Drosophila melanogaster/microbiologia , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/metabolismo , Embrião não Mamífero/microbiologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Histonas/metabolismo , Histonas/farmacologia , Gotículas Lipídicas/química , Gotículas Lipídicas/metabolismo , Lipopolissacarídeos/farmacologia , Listeria monocytogenes/efeitos dos fármacos , Listeria monocytogenes/crescimento & desenvolvimento , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/microbiologia , Camundongos , Camundongos Endogâmicos C57BL , Staphylococcus epidermidis/efeitos dos fármacos , Staphylococcus epidermidis/crescimento & desenvolvimento , Ácidos Teicoicos/farmacologia
5.
J Vis Exp ; (62)2012 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-22565641

RESUMO

Motor proteins move cargoes along microtubules, and transport them to specific sub-cellular locations. Because altered transport is suggested to underlie a variety of neurodegenerative diseases, understanding microtubule based motor transport and its regulation will likely ultimately lead to improved therapeutic approaches. Kinesin-1 is a eukaryotic motor protein which moves in an anterograde (plus-end) direction along microtubules (MTs), powered by ATP hydrolysis. Here we report a detailed purification protocol to isolate active full length kinesin from Drosophila embryos, thus allowing the combination of Drosophila genetics with single-molecule biophysical studies. Starting with approximately 50 laying cups, with approximately 1000 females per cup, we carried out overnight collections. This provided approximately 10 ml of packed embryos. The embryos were bleach dechorionated (yielding approximately 9 grams of embryos), and then homogenized. After disruption, the homogenate was clarified using a low speed spin followed by a high speed centrifugation. The clarified supernatant was treated with GTP and taxol to polymerize MTs. Kinesin was immobilized on polymerized MTs by adding the ATP analog, 5'-adenylyl imidodiphosphate at room temperature. After kinesin binding, microtubules were sedimented via high speed centrifugation through a sucrose cushion. The microtubule pellet was then re-suspended, and this process was repeated. Finally, ATP was added to release the kinesin from the MTs. High speed centrifugation then spun down the MTs, leaving the kinesin in the supernatant. This kinesin was subjected to a centrifugal filtration using a 100 KD cut off filter for further purification, aliquoted, snap frozen in liquid nitrogen, and stored at -80 °C. SDS gel electrophoresis and western blotting was performed using the purified sample. The motor activity of purified samples before and after the final centrifugal filtration step was evaluated using an in vitro single molecule microtubule assay. The kinesin fractions before and after the centrifugal filtration showed processivity as previously reported in literature. Further experiments are underway to evaluate the interaction between kinesin and other transport related proteins.


Assuntos
Drosophila/química , Cinesinas/isolamento & purificação , Animais , Drosophila/embriologia , Embrião não Mamífero , Feminino , Fracionamento por Campo e Fluxo/métodos , Coloração pela Prata/métodos
6.
Nat Commun ; 3: 754, 2012 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-22453827

RESUMO

Kinesin-1 is a plus-end microtubule-based motor, and defects in kinesin-based transport are linked to diseases including neurodegeneration. Kinesin can auto-inhibit via a head-tail interaction, but is believed to be active otherwise. Here we report a tail-independent inactivation of kinesin, reversible by the disease-relevant signalling protein, casein kinase 2 (CK2). The majority of initially active kinesin (native or tail-less) loses its ability to interact with microtubules in vitro, and CK2 reverses this inactivation (approximately fourfold) without altering kinesin's single motor properties. This activation pathway does not require motor phosphorylation, and is independent of head-tail auto-inhibition. In cultured mammalian cells, reducing CK2 expression, but not its kinase activity, decreases the force required to stall lipid droplet transport, consistent with a decreased number of active kinesin motors. Our results provide the first direct evidence of a protein kinase upregulating kinesin-based transport, and suggest a novel pathway for regulating the activity of cargo-bound kinesin.


Assuntos
Caseína Quinase II/metabolismo , Cinesinas/metabolismo , Microtúbulos/metabolismo , Animais , Células COS , Linhagem Celular , Chlorocebus aethiops , Cinesinas/química , Metabolismo dos Lipídeos , Fosforilação , Interferência de RNA , RNA Interferente Pequeno
7.
Proc Natl Acad Sci U S A ; 108(47): 18960-5, 2011 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-22084076

RESUMO

Intracellular transport via the microtubule motors kinesin and dynein plays an important role in maintaining cell structure and function. Often, multiple kinesin or dynein motors move the same cargo. Their collective function depends critically on the single motors' detachment kinetics under load, which we experimentally measure here. This experimental constraint--combined with other experimentally determined parameters--is then incorporated into theoretical stochastic and mean-field models. Comparison of modeling results and in vitro data shows good agreement for the stochastic, but not mean-field, model. Many cargos in vivo move bidirectionally, frequently reversing course. Because both kinesin and dynein are present on the cargos, one popular hypothesis explaining the frequent reversals is that the opposite-polarity motors engage in unregulated stochastic tugs-of-war. Then, the cargos' motion can be explained entirely by the outcome of these opposite-motor competitions. Here, we use fully calibrated stochastic and mean-field models to test the tug-of-war hypothesis. Neither model agrees well with our in vivo data, suggesting that, in addition to inevitable tugs-of-war between opposite motors, there is an additional level of regulation not included in the models.


Assuntos
Metabolismo dos Lipídeos , Modelos Biológicos , Proteínas Motores Moleculares/metabolismo , Processos Estocásticos , Transporte Biológico/fisiologia , Simulação por Computador , Cinética
8.
Biochem Pharmacol ; 82(12): 1901-9, 2011 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-21924245

RESUMO

Curcumin, a diferuloylmethane, has been shown to exhibit anti-inflammatory and anti-proliferative activities. Whereas curcumin has both a Michael acceptor and a Michael donor units, its analogues dibenzoylmethane (DBM, a component of licorice) and dibenzoylpropane (DBP) have a Michael donor but not a Michael acceptor unit, and the analogue dibenzylideneacetone (DBA) has a Michael acceptor unit. In the current report, we investigated the potency of DBM, DBP, and DBA in relation to curcumin for their ability to suppress TNF-induced NF-κB activation, NF-κB-regulated gene products, and cell proliferation. We found that all four agents were active in suppressing NF-κB activation; curcumin was most active and DBM was least active. When examined for its ability to inhibit the direct DNA binding activity of p65, a subunit of NF-κB, only DBP inhibited the binding. For inhibition of TNF-induced IKK activation, DBA was most active. For suppression of TNF-induced expression of NF-κB-regulated gene products such as COX-2 (inflammation marker), cyclin D1 (proliferation marker), and VEGF (angiogenesis marker), DBA and curcumin were more active than DBM. Similarly for suppression of proliferation of leukemia (KBM-5), T cell leukemia (Jurkat), prostate (DU145), and breast (MDA-MB-231) cancer cells, curcumin and DBA were most active and DBP was least active. Overall, our results indicate that although curcumin and its analogues exhibit activities to suppress inflammatory pathways and cellular proliferation, a lack of Michael acceptor units in DBM and DBP can reduce their activities.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Chalconas/farmacologia , Curcumina/farmacologia , Pentanonas/farmacologia , Proteínas Angiogênicas/genética , Proteínas Angiogênicas/metabolismo , Anti-Inflamatórios não Esteroides/química , Linhagem Celular Tumoral , Proliferação de Células , Chalconas/química , Curcumina/análogos & derivados , Curcumina/química , Regulação da Expressão Gênica/fisiologia , Humanos , MAP Quinase Quinase Quinases/genética , MAP Quinase Quinase Quinases/metabolismo , Estrutura Molecular , Pentanonas/química , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
9.
Neoplasia ; 12(10): 766-77, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20927315

RESUMO

The transcription factor nuclear factor-κB (NF-κB) is a central mediator of growth and homeostasis for both normal and neoplastic cells. IκBα is the natural intracellular inhibitor of NF-κB and can effectively complex with and thereby inhibit the biologic activity and translocation of NF-κB to the nucleus. We designed a fusion protein designated IκBα/scFvMEL composing of human IκBα and the single-chain antibody scFvMEL, targets melanoma gp240 antigen. Cells treated with IκBα/scFvMEL before irradiation showed specifically inhibition of both constitutive and radiation-induced NF-κB activity on gp240 antigen-positive A375M cells. Pretreatment of A375M cells with IκBα/scFvMEL significantly sensitized melanoma cells to ionizing radiation assessed using a clonogenic survival assay. Mechanistic studies showed that IκBα/scFvMEL, when exogenously added to A375M cells, could be coimmunoprecipitated with the p65 subunit of NF-κB. IκBα/scFvMEL inhibited in a time and/or dose-dependent manner of tumor necrosis factor α- or radiation-induced NF-κB activity in vitro. IκBα/scFvMEL was also shown to specifically inhibit the translocation of the NF-κB p65 subunit to the cell nucleus and NF-κB-mediated gene transcription. Further, initial studies showed that mice bearing well-established A375M xenografts were treated (intravenously) with IκBα/scFvMEL and showed a significant suppression of tumor growth. We also observed a decrease in levels of Bcl-2 and Bcl-XL signaling events downstream of NF-κB in the tumor model. These studies demonstrate for the first time that tumor cell-targeted delivery of IκBα may be beneficial for the treatment of melanoma when combined with standard anticancer therapies such as radiation.


Assuntos
Proteínas I-kappa B/uso terapêutico , Melanoma Experimental/terapia , NF-kappa B/antagonistas & inibidores , Proteoglicanas/imunologia , Radiossensibilizantes/farmacologia , Proteínas Recombinantes de Fusão/uso terapêutico , Anticorpos de Cadeia Única/uso terapêutico , Animais , Apoptose , Western Blotting , Núcleo Celular/genética , Núcleo Celular/metabolismo , Núcleo Celular/efeitos da radiação , Relação Dose-Resposta a Droga , Ensaio de Desvio de Mobilidade Eletroforética , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Humanos , Técnicas Imunoenzimáticas , Melanoma Experimental/genética , Melanoma Experimental/patologia , Camundongos , Camundongos Nus , Inibidor de NF-kappaB alfa , Fosforilação , Transporte Proteico/efeitos da radiação , RNA Mensageiro/genética , Radiação Ionizante , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/efeitos da radiação , Fator de Transcrição RelA/metabolismo , Fator de Necrose Tumoral alfa/farmacologia
10.
Int J Cancer ; 127(2): 257-68, 2010 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-19908231

RESUMO

Gemcitabine, while a standard treatment of advanced pancreatic cancer (PaCa), alone is not very effective. New agents that are safe and effective are highly needed. Resveratrol is one such agent which is safe and multitargeted; and has been linked with suppression of survival, proliferation, invasion and angiogenesis of cancer. Whether resveratrol can sensitize PaCa to gemcitabine in vitro and in vivo was investigated. We established PaCa xenografts in nude mice, randomized into 4 groups, and treated with vehicle, gemcitabine, resveratrol and with combination. Modulation of NF-kappaB and markers of proliferation, angiogenesis and invasion were ascertained using electrophoretic mobility shift assay (EMSA), immunohistochemistry and western blot analysis. Resveratrol inhibited the proliferation of 4 different human PaCa cell lines, synergized the apoptotic effects of gemcitabine, inhibited the constitutive activation of NF-kappaB and expression of bcl-2, bcl-xL, COX-2, cyclin D1 MMP-9 and VEGF. In an orthotopic model of human PaCa, we found that resveratrol significantly suppressed the growth of the tumor (p < 0.001) and this effect was further enhanced by gemcitabine (p < 0.001). Both the markers of proliferation index Ki-67 and the micro vessel density CD31 were significantly downregulated in tumor tissue by the combination of gemcitabine and resveratrol (p < 0.001 vs. control; p < 0.01 vs. gemcitabine). As compared to vehicle control, resveratrol also suppressed the NF-kappaB activation and expression of cyclin D1, COX-2, ICAM-1, MMP-9 and survivin. Overall our results demonstrate that resveratrol can potentiate the effects of gemcitabine through suppression of markers of proliferation, invasion, angiogenesis and metastasis.


Assuntos
Adenocarcinoma/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Ductal Pancreático/tratamento farmacológico , Neoplasias Pancreáticas/tratamento farmacológico , Ensaios Antitumorais Modelo de Xenoenxerto , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Animais , Apoptose/efeitos dos fármacos , Western Blotting , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/patologia , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ciclo-Oxigenase 2/metabolismo , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Humanos , Técnicas Imunoenzimáticas , Técnicas In Vitro , Masculino , Camundongos , Camundongos Nus , NF-kappa B/genética , NF-kappa B/metabolismo , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Resveratrol , Estilbenos/administração & dosagem , Células Tumorais Cultivadas , Fator A de Crescimento do Endotélio Vascular/metabolismo , Gencitabina
11.
Biochem Pharmacol ; 79(3): 330-8, 2010 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-19735646

RESUMO

Curcumin, a yellow pigment present in the spice turmeric (Curcuma longa), has been linked with antioxidant, anti-inflammatory, antiproliferative, anticancer, antidiabetic, antirheumatic, and antiviral effects, but its optimum potential is limited by its lack of solubility in aqueous solvents and poor oral bioavailability. We employed a polymer-based nanoparticle approach to improve bioavailability. Curcumin was encapsulated with 97.5% efficiency in biodegradable nanoparticulate formulation based on poly (lactide-co-glycolide) (PLGA) and a stabilizer polyethylene glycol (PEG)-5000. Dynamic laser light scattering and transmission electron microscopy indicated a particle diameter of 80.9 nm. This curcumin, renamed from hereon "as curcumin (NP)", was characterized for its biological activity. In vitro curcumin (NP) exhibited very rapid and more efficient cellular uptake than curcumin. Estrase staining revealed that curcumin (NP) was at least as potent as or more potent than curcumin in inducing apoptosis of leukemic cells and in suppressing proliferation of various tumor cell lines. When examined by electrophoretic gel shift mobility assay, curcumin (NP) was more active than curcumin in inhibiting TNF-induced NF-kappaB activation and in suppression of NF-kappaB-regulated proteins involved in cell proliferation (cyclin D1), invasion (MMP-9), and angiogenesis (VEGF). In mice, curcumin (NP) was more bioavailable and had a longer half-life than curcumin. Overall we demonstrate that curcumin-loaded PLGA nanoparticles formulation has enhanced cellular uptake, and increased bioactivity in vitro and superior bioavailability in vivo over curcumin.


Assuntos
Curcumina/síntese química , Curcumina/metabolismo , Desenho de Fármacos , Endocitose , Ácido Láctico/síntese química , Ácido Láctico/metabolismo , Nanopartículas , Ácido Poliglicólico/síntese química , Ácido Poliglicólico/metabolismo , Animais , Disponibilidade Biológica , Química Farmacêutica , Endocitose/fisiologia , Células HCT116 , Humanos , Células Jurkat , Camundongos , Camundongos Endogâmicos BALB C , Nanopartículas/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico
12.
Int J Cancer ; 125(9): 2187-97, 2009 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-19623659

RESUMO

Because of the poor prognosis and the development of resistance against chemotherapeutic drugs, the current treatment for advanced metastatic colorectal cancer (CRC) is ineffective. Whether curcumin (a component of turmeric) can potentiate the effect of capecitabine against growth and metastasis of CRC was investigated. The effect of curcumin on proliferation of CRC cell lines was examined by mitochondrial dye-uptake assay, apoptosis by esterase staining, nuclear factor-kappaB (NF-kappaB) by electrophoretic mobility shift assay and gene expression by Western blot analysis. The effect of curcumin on the growth and metastasis of CRC was also examined in orthotopically implanted tumors in nude mice. In vitro, curcumin inhibited the proliferation of human CRC cell lines, potentiated capecitabine-induced apoptosis, inhibited NF-kappaB activation and suppressed NF-kappaB-regulated gene products. In nude mice, the combination of curcumin and capecitabine was found to be more effective than either agent alone in reducing tumor volume (p = 0.001 vs. control; p = 0.031 vs. capecitabine alone), Ki-67 proliferation index (p = 0.001 vs. control) and microvessel density marker CD31. The combination treatment was also highly effective in suppressing ascites and distant metastasis to the liver, intestines, lungs, rectum and spleen. This effect was accompanied by suppressed expression of activated NF-kappaB and NF-kappaB-regulated gene products (cyclin D1,c-myc, bcl-2, bcl-xL, cIAP-1, COX-2, ICAM-1, MMP-9, CXCR4 and VEGF). Overall, our results suggest that curcumin sensitizes CRC to the antitumor and antimetastatic effects of capecitabine by suppressing NF-kappaB cell signaling pathway.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Colorretais/tratamento farmacológico , Curcumina/farmacologia , Ciclina D1/genética , Ciclo-Oxigenase 2/genética , Desoxicitidina/análogos & derivados , Fluoruracila/análogos & derivados , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Metaloproteinase 9 da Matriz/genética , Fator A de Crescimento do Endotélio Vascular/genética , Animais , Apoptose/efeitos dos fármacos , Capecitabina , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Desoxicitidina/farmacologia , Sinergismo Farmacológico , Fluoruracila/farmacologia , Humanos , Masculino , Camundongos , NF-kappa B/antagonistas & inibidores , Metástase Neoplásica/prevenção & controle , Receptores CXCR4
13.
Mol Cancer Ther ; 8(4): 959-70, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19372569

RESUMO

Curcumin (diferuloylmethane), a yellow pigment in turmeric, has been shown to inhibit the activation of nuclear factor-kappaB (NF-kappaB), a transcription factor closely linked to chemoresistance in multiple myeloma cells. Whether curcumin can overcome chemoresistance and enhance the activity of thalidomide and bortezomib, used to treat patients with multiple myeloma, was investigated in vitro and in xenograft model in nude mice. Our results show that curcumin inhibited the proliferation of human multiple myeloma cells regardless of their sensitivity to dexamethasone, doxorubicin, or melphalan. Curcumin also potentiated the apoptotic effects of thalidomide and bortezomib by down-regulating the constitutive activation of NF-kappaB and Akt, and this correlated with the suppression of NF-kappaB-regulated gene products, including cyclin D1, Bcl-xL, Bcl-2, TRAF1, cIAP-1, XIAP, survivin, and vascular endothelial growth factor. Furthermore, in a nude mice model, we found that curcumin potentiated the antitumor effects of bortezomib (P<0.001, vehicle versus bortezomib+curcumin; P<0.001, bortezomib versus bortezomib+curcumin), and this correlated with suppression of Ki-67 (P<0.001 versus control), CD31 (P<0.001 versus vehicle), and vascular endothelial growth factor (P<0.001 versus vehicle) expression. Collectively, our results suggest that curcumin overcomes chemoresistance and sensitizes multiple myeloma cells to thalidomide and bortezomib by down-regulating NF-kappaB and NF-kappaB-regulated gene products.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Apoptose/efeitos dos fármacos , Modelos Animais de Doenças , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Mieloma Múltiplo/tratamento farmacológico , Animais , Western Blotting , Ácidos Borônicos/administração & dosagem , Bortezomib , Proliferação de Células/efeitos dos fármacos , Curcumina/administração & dosagem , Sinergismo Farmacológico , Humanos , Técnicas Imunoenzimáticas , Masculino , Camundongos , Camundongos Nus , Mieloma Múltiplo/metabolismo , Mieloma Múltiplo/patologia , NF-kappa B/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Pirazinas/administração & dosagem , Transdução de Sinais , Talidomida/administração & dosagem , Fator A de Crescimento do Endotélio Vascular/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
14.
Blood ; 113(9): 2003-13, 2009 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-18952893

RESUMO

Xanthohumol (XN), a prenylated chalcone isolated from hop plant, exhibits anti-inflammatory, antiproliferative, and antiangiogenic properties through an undefined mechanism. Whether examined by intracellular esterase activity, phosphatidylserine externalization, DNA strand breaks, or caspase activation, we found that XN potentiated tumor necrosis factor-induced apoptosis in leukemia and myeloma cells. This enhancement of apoptosis correlated with down-regulation of nuclear factor-kappaB (NF-kappaB) survivin, bcl-xL, XIAP, cIAP1, cIAP2, cylin D1, and c-myc. XN down-regulated both constitutive and inducible NF-kappaB activation, inhibition of phosphorylation and degradation of IkappaBalpha, suppression of p65 nuclear translocation, and NF-kappaB-dependent reporter gene transcription. XN directly inhibited tumor necrosis factor-induced IkappaBalpha kinase (IKK) activation and a reducing agent abolished this inhibition, indicating the role of cysteine residue. XN had no effect on the IKK activity when cysteine residue 179 of IKK was mutated to alanine. XN also directly inhibited binding of p65 to DNA, a reducing agent reversed this effect, and mutation of cysteine residue 38 to serine of p65 abolished this effect. Thus, our results show that modification of cysteine residues of IKK and p65 by XN leads to inhibition of the NF-kappaB activation pathway, suppression of antiapoptotic gene products, and potentiation of apoptosis in leukemia cells.


Assuntos
Apoptose/efeitos dos fármacos , Cisteína/efeitos dos fármacos , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Quinase I-kappa B/efeitos dos fármacos , Leucemia/patologia , Propiofenonas/farmacologia , Fator de Transcrição RelA/efeitos dos fármacos , Substituição de Aminoácidos/fisiologia , Apoptose/genética , Movimento Celular/efeitos dos fármacos , Movimento Celular/genética , Proliferação de Células/efeitos dos fármacos , Cisteína/química , Cisteína/genética , Flavonoides , Células HL-60 , Humanos , Quinase I-kappa B/química , Quinase I-kappa B/genética , Quinase I-kappa B/metabolismo , Células Jurkat , Células K562 , Leucemia/genética , Leucemia/metabolismo , Mieloma Múltiplo/genética , Mieloma Múltiplo/metabolismo , Mieloma Múltiplo/patologia , Invasividade Neoplásica , Oxirredução/efeitos dos fármacos , Fator de Transcrição RelA/química , Fator de Transcrição RelA/genética , Fator de Transcrição RelA/metabolismo , Células Tumorais Cultivadas , Regulação para Cima/efeitos dos fármacos
15.
Cancer Res ; 68(21): 8861-70, 2008 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-18974130

RESUMO

Picroliv, an iridoid glycoside derived from the plant Picrorhiza kurroa, is used traditionally to treat fever, asthma, hepatitis, and other inflammatory conditions. However, the exact mechanism of its therapeutic action is still unknown. Because nuclear factor-kappaB (NF-kappaB) activation plays a major role in inflammation and carcinogenesis, we postulated that picroliv must interfere with this pathway by inhibiting the activation of NF-kappaB-mediated signal cascade. Electrophoretic mobility shift assay showed that pretreatment with picroliv abrogated tumor necrosis factor (TNF)-induced activation of NF-kappaB. The glycoside also inhibited NF-kappaB activated by carcinogenic and inflammatory agents, such as cigarette smoke condensate, phorbol 12-myristate 13-acetate, okadaic acid, hydrogen peroxide, lipopolysaccharide, and epidermal growth factor. When examined for the mechanism of action, we found that picroliv inhibited activation of IkappaBalpha kinase, leading to inhibition of phosphorylation and degradation of IkappaBalpha. It also inhibited phosphorylation and nuclear translocation of p65. Further studies revealed that picroliv directly inhibits the binding of p65 to DNA, which was reversed by the treatment with reducing agents, suggesting a role for a cysteine residue in interaction with picroliv. Mutation of Cys(38) in p65 to serine abolished this effect of picroliv. NF-kappaB inhibition by picroliv leads to suppression of NF-kappaB-regulated proteins, including those linked with cell survival (inhibitor of apoptosis protein 1, Bcl-2, Bcl-xL, survivin, and TNF receptor-associated factor 2), proliferation (cyclin D1 and cyclooxygenase-2), angiogenesis (vascular endothelial growth factor), and invasion (intercellular adhesion molecule-1 and matrix metalloproteinase-9). Suppression of these proteins enhanced apoptosis induced by TNF. Overall, our results show that picroliv inhibits the NF-kappaB activation pathway, which may explain its anti-inflammatory and anticarcinogenic effects.


Assuntos
Apoptose/fisiologia , Cinamatos/farmacologia , Cisteína/química , Glicosídeos/farmacologia , NF-kappa B/fisiologia , Ácido Vanílico/farmacologia , Western Blotting , Linhagem Celular Tumoral , DNA de Neoplasias/metabolismo , Eletroforese em Gel de Poliacrilamida , Ensaio de Desvio de Mobilidade Eletroforética , Humanos , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , NF-kappa B/química , NF-kappa B/metabolismo , Fosforilação , Transporte Proteico , Fator de Necrose Tumoral alfa/fisiologia
16.
Mol Cancer Ther ; 7(10): 3306-17, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18852134

RESUMO

Compounds isolated from members of the Zingiberaceae family are traditionally used as a medicine against inflammatory diseases, but little is known about the mechanism. Here, we report the isolation and structural identification of coronarin D [E-labda-8(17),12-diene-15-ol], a labdane-type diterpene, from Hedychium coronarium and delineate its mechanism of action. Because the transcription factor nuclear factor-kappaB (NF-kappaB) is a key mediator of inflammation, apoptosis, invasion, and osteoclastogenesis, we investigated the effect of coronarin D on NF-kappaB activation pathway, NF-kappaB-regulated gene products, and NF-kappaB-regulated cellular responses. The coronarin D inhibited NF-kappaB activation induced by different inflammatory stimuli and carcinogens. This labdane also suppressed constitutive NF-kappaB activity in different cell lines and inhibited IkappaBalpha kinase activation, thus leading to the suppression of IkappaBalpha phosphorylation, degradation, p65 nuclear translocation, and reporter gene transcription. Coronarin D also inhibited the NF-kappaB-regulated gene products involved in cell survival (inhibitor of apoptosis protein 1, Bcl-2, survivin, and tumor necrosis factor receptor-associated factor-2), proliferation (c-myc, cyclin D1, and cyclooxygenase-2), invasion (matrix metalloproteinase-9), and angiogenesis (vascular endothelial growth factor). Suppression of these gene products by the diterpene enhanced apoptosis induced by TNF and chemotherapeutic agents, suppressed TNF-induced cellular invasion, and abrogated receptor activator of NF-kappaB ligand-induced osteoclastogenesis. Coronarin D was found to be more potent than its analogue coronarin D acid. Overall, our results show that coronarin D inhibited NF-kappaB activation pathway, which leads to inhibition of inflammation, invasion, and osteoclastogenesis, as well as potentiation of apoptosis.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Diterpenos/farmacologia , NF-kappa B/metabolismo , Osteoclastos/citologia , Osteoclastos/efeitos dos fármacos , Animais , Antineoplásicos/química , Linhagem Celular Tumoral , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Diterpenos/química , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Genes Reporter , Humanos , Proteínas I-kappa B/metabolismo , Camundongos , Inibidor de NF-kappaB alfa , Invasividade Neoplásica , Metástase Neoplásica , Proteínas de Neoplasias/metabolismo , Fosforilação/efeitos dos fármacos , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Transporte Proteico/efeitos dos fármacos , Ligante RANK/farmacologia , Fator de Transcrição RelA/metabolismo , Fator de Necrose Tumoral alfa/farmacologia
17.
Biochem Pharmacol ; 76(11): 1590-611, 2008 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-18775680

RESUMO

Curcumin, a yellow pigment present in the Indian spice turmeric (associated with curry powder), has been linked with suppression of inflammation; angiogenesis; tumorigenesis; diabetes; diseases of the cardiovascular, pulmonary, and neurological systems, of skin, and of liver; loss of bone and muscle; depression; chronic fatigue; and neuropathic pain. The utility of curcumin is limited by its color, lack of water solubility, and relatively low in vivo bioavailability. Because of the multiple therapeutic activities attributed to curcumin, however, there is an intense search for a "super curcumin" without these problems. Multiple approaches are being sought to overcome these limitations. These include discovery of natural curcumin analogues from turmeric; discovery of natural curcumin analogues made by Mother Nature; synthesis of "man-made" curcumin analogues; reformulation of curcumin with various oils and with inhibitors of metabolism (e.g., piperine); development of liposomal and nanoparticle formulations of curcumin; conjugation of curcumin prodrugs; and linking curcumin with polyethylene glycol. Curcumin is a homodimer of feruloylmethane containing a methoxy group and a hydroxyl group, a heptadiene with two Michael acceptors, and an alpha,beta-diketone. Structural homologues involving modification of all these groups are being considered. This review focuses on the status of all these approaches in generating a "super curcumin.".


Assuntos
Produtos Biológicos/farmacologia , Curcumina/farmacologia , Animais , Produtos Biológicos/química , Curcumina/análogos & derivados , Curcumina/química , Humanos , Relação Estrutura-Atividade
18.
Planta Med ; 74(13): 1560-9, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18612945

RESUMO

Although spices have been used for thousands of years and are known for their flavor, taste and color in the food, they are not usually recognized for their medicinal value. Extensive research within the last two decades from our laboratory and others has indicated that there are phytochemicals present in spices that may prevent various chronic illnesses including cancerous, diabetic, cardiovascular, pulmonary, neurological and autoimmune diseases. For instance, the potential of turmeric (curcumin), red chilli (capsaicin), cloves (eugenol), ginger (zerumbone), fennel (anethole), kokum (gambogic acid), fenugreek (diosgenin), and black cumin (thymoquinone) in cancer prevention has been established. Additionally, the mechanism by which these agents mediate anticancer effects is also becoming increasingly evident. The current review describes the active components of some of the major spices, their mechanisms of action and their potential in cancer prevention.


Assuntos
Anticarcinógenos/química , Anticarcinógenos/farmacologia , Neoplasias/prevenção & controle , Fitoterapia , Especiarias/análise , Humanos , Plantas/química
19.
Pharm Res ; 25(9): 2097-116, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18626751

RESUMO

This year, more than 1 million Americans and more than 10 million people worldwide are expected to be diagnosed with cancer, a disease commonly believed to be preventable. Only 5-10% of all cancer cases can be attributed to genetic defects, whereas the remaining 90-95% have their roots in the environment and lifestyle. The lifestyle factors include cigarette smoking, diet (fried foods, red meat), alcohol, sun exposure, environmental pollutants, infections, stress, obesity, and physical inactivity. The evidence indicates that of all cancer-related deaths, almost 25-30% are due to tobacco, as many as 30-35% are linked to diet, about 15-20% are due to infections, and the remaining percentage are due to other factors like radiation, stress, physical activity, environmental pollutants etc. Therefore, cancer prevention requires smoking cessation, increased ingestion of fruits and vegetables, moderate use of alcohol, caloric restriction, exercise, avoidance of direct exposure to sunlight, minimal meat consumption, use of whole grains, use of vaccinations, and regular check-ups. In this review, we present evidence that inflammation is the link between the agents/factors that cause cancer and the agents that prevent it. In addition, we provide evidence that cancer is a preventable disease that requires major lifestyle changes.


Assuntos
Anticarcinógenos/uso terapêutico , Neoplasias/prevenção & controle , Comportamento de Redução do Risco , Consumo de Bebidas Alcoólicas/efeitos adversos , Restrição Calórica , Dieta/efeitos adversos , Fibras na Dieta/administração & dosagem , Poluentes Ambientais/efeitos adversos , Exercício Físico , Frutas , Humanos , Infecções/complicações , Estilo de Vida , Neoplasias/etiologia , Neoplasias Induzidas por Radiação/prevenção & controle , Obesidade/complicações , Extratos Vegetais/uso terapêutico , Fatores de Risco , Fumar/efeitos adversos , Verduras , Vitaminas/uso terapêutico
20.
Cancer Lett ; 269(2): 199-225, 2008 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-18479807

RESUMO

Because most cancers are caused by dysregulation of as many as 500 different genes, agents that target multiple gene products are needed for prevention and treatment of cancer. Curcumin, a yellow coloring agent in turmeric, has been shown to interact with a wide variety of proteins and modify their expression and activity. These include inflammatory cytokines and enzymes, transcription factors, and gene products linked with cell survival, proliferation, invasion, and angiogenesis. Curcumin has been found to inhibit the proliferation of various tumor cells in culture, prevents carcinogen-induced cancers in rodents, and inhibits the growth of human tumors in xenotransplant or orthotransplant animal models either alone or in combination with chemotherapeutic agents or radiation. Several phase I and phase II clinical trials indicate that curcumin is quite safe and may exhibit therapeutic efficacy. These aspects of curcumin are discussed further in detail in this review.


Assuntos
Inibidores da Angiogênese/farmacologia , Antineoplásicos/farmacologia , Curcumina/farmacologia , Neoplasias/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos , Animais , Neoplasias da Mama/prevenção & controle , Proliferação de Células/efeitos dos fármacos , Ensaios Clínicos como Assunto , Curcumina/química , Curcumina/farmacocinética , Curcumina/uso terapêutico , Neoplasias Gastrointestinais/prevenção & controle , Humanos , Interleucinas/antagonistas & inibidores , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , NF-kappa B/antagonistas & inibidores , Invasividade Neoplásica , Metástase Neoplásica/prevenção & controle , PPAR gama/efeitos dos fármacos , Fatores de Transcrição STAT/antagonistas & inibidores , Fator de Transcrição AP-1/antagonistas & inibidores , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores
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