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1.
Curr Cancer Drug Targets ; 19(4): 296-303, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30968769

RESUMO

BACKGROUND: Highly Active Metastasis Preventing Therapy (HAMPT) is a quardruple drug combination consisting of mifepristone, aspirin, lysine and doxycycline. OBJECTIVE: Based on our previous study, here, we further proved that HAMPT could effectively and safely prevent colon cancer metastasis. METHODS: It was specifically designed for synergistically controlling key cancer metastatic pathways. The dose of HAMPT was designed at lower than the pharmaceutically-recommended dose, and thus the sub-healthy cancer survivors may take HAMPT safely and for a long time for metastasis chemoprevention. RESULTS: HAMPT within its effective concentration range (1-50 µg/mL) showed no cytotoxicity to colon cancer cells HT-29 and CT-26, but significantly inhibited adhesion and invasion of these colon cancer cell lines to human umbilical vascular endothelial cells (HUVECs), and to Matrigel. HAMPT exhibits a good adhesion inhibited ratio, suggesting that it functions primarily by inhibiting adhesion of the cancer cells to HUVECs, rather than killing the cancer cells. At low concentrations, HAMPT also inhibited cancer cell migration. Flow cytometry analysis revealed that HAMPT had no significant effect on cell cycle, but inhibited IL-1ß-induced expression of both E-selectin of HUVECs and Sialyl-Lewis X of HT-29. The in vivo experiment showed that HAMPT suppressed metastasis of CT-26 cells to mouse lungs in a dose-dependent manner. In the mouse model, HAMPT showed advantages in preventing metastasis over other combinations. CONCLUSION: The present study demonstrated that HAMPT is a novel quadruple drug combination that can safely and effectively prevent cancer metastasis.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Aspirina/farmacologia , Neoplasias do Colo/tratamento farmacológico , Doxiciclina/farmacologia , Lisina/farmacologia , Mifepristona/farmacologia , Animais , Antibacterianos/farmacologia , Anti-Inflamatórios não Esteroides/farmacologia , Apoptose , Ciclo Celular , Proliferação de Células , Neoplasias do Colo/patologia , Quimioterapia Combinada , Feminino , Antagonistas de Hormônios/farmacologia , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Estudo de Prova de Conceito , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
2.
J Mol Neurosci ; 67(2): 217-226, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30484061

RESUMO

Microglia play an essential role during cerebral an ischemia/reperfusion (I/R)-related inflammatory process. Because the M2 phenotype of microglia exhibits anti-inflammation activity, it has become a promising target for anti-inflammatory therapy. Vagus nerve stimulation (VNS) reportedly has neuroprotective effects against cerebral I/R injuries via its anti-inflammatory action. The aim of this study was to investigate the ability of non-invasive VNS (nVNS) to alleviate cerebral I/R in mice by promoting microglial M2 polarization. Neurological scoring and cerebral infarct volume assessments were performed 72 h after a middle cerebral artery occlusion (MCAO)-induced stroke. M2 phenotype microglia were identified by immunohistochemistry staining using Arg-1 and Iba-1 antibodies. The protein expressions of Arg-1, IL-17A, IL-10, Bax, and Bcl-2 were detected by Western blot. Apoptotic cells were detected using TUNEL staining. According to our results, nVNS decreased infarct volume, improved neurological outcomes, reduced apoptotic neurons (TUNEL+NeuN+ cells), and promoted microglial M2 polarization as indicated by elevated Arg-1 protein expression and increased Arg-1+ cells after MCAO. Moreover, nVNS attenuated the increased levels of IL-17A protein expression after MCAO. To test the possible involvement of IL-17A in nVNS-induced neuroprotection and microglial M2 polarization, 1-µg recombinant IL-17A (rIL-17A) was intranasally administered once daily for three consecutive days after reperfusion. We found that the intranasal administration of rIL-17A nullified the nVNS-induced promotion of microglial M2 polarization. Furthermore, rIL-17A administration abolished the neuroprotective effect of nVNS. In conclusion, our study identifies microglial M2 polarization as an important mechanism underlying the nVNS-mediated neuroprotection against cerebral I/R. This effect of nVNS could be attributed to the inhibition of IL-17A expression.


Assuntos
Infarto da Artéria Cerebral Média/terapia , Interleucina-17/metabolismo , Estimulação do Nervo Vago/métodos , Animais , Apoptose , Encéfalo/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microglia/metabolismo , Neurônios/metabolismo
3.
Toxicol Mech Methods ; 26(1): 36-45, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26907462

RESUMO

OBJECTIVE: Mifepristone (RU486) is an oral first-line contraceptive used by hundreds of millions of women, and recently it was tested for anticancer activity in both genders worldwide. We are developing metapristone (the N-monodemethyl RU486) as a potential metastasis chemopreventive. The present acute and 30-d subacute toxicity study aimed at examining and compared in parallel the potential toxicity of the two drugs. METHODS: The single-dose acute toxicity and 30-d subacute toxicity studies were conducted in mice and rats, respectively, by gavaging metapristone or mifepristone at various doses. Blood samples and organs were collected for blood chemistry, hematology and histology analyses. RESULTS: Oral mifepristone (3000 mg/kg) caused 30% and 40% death in female and male mice, respectively, within 15 h post-dosing. In comparison, the same dose of metapristone produced 30% acute death in males only. Thirty-day oral administration of the two drugs to rats (12.5, 50 and 200 mg/kg/day) caused reversible hepatotoxicity that only occurred at 200 mg/kg/day group, evidenced by the elevated liver enzyme activity and liver organ weight. CONCLUSION: The present study, for the first time, reveals reversible hepatotoxicity in rats caused by the 30-d consecutive administration at the high dose, and warns the potential hepatotoxicity caused by long-term administrations of high doses of mifepristone or metapristone in clinical trials but not by the acute single abortion doses.


Assuntos
Abortivos Esteroides/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/patologia , Mifepristona/análogos & derivados , Mifepristona/toxicidade , Abortivos Esteroides/administração & dosagem , Animais , Feminino , Masculino , Mifepristona/administração & dosagem , Ratos
4.
Oncotarget ; 6(34): 35157-72, 2015 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-26459390

RESUMO

Recent scientific advances have increased our understanding of the cancer metastatic complexities and provided further impetus for new combination therapies to prevent cancer metastasis. Here, we demonstrated that a combination (HAMPT) of aspirin, lysine, mifepristone and doxycycline can effectively and safely prevent cancer metastasis. The pharmaceutically-formulated HAMPT inhibited adhesion of cancer cells to either endothelial cells or extracellular matrix via down-regulating cell adhesion molecules ICAM-1 and α4-integrin. HAMPT inhibited the cloak effect by activated platelets on cancer cells, thereby interfering adhesion and invasion of cancer cells to the underlying stroma. At the effective concentration, HAMPT induced cancer cells into dormancy with minor inhibition on cell viability. Four-day pretreatment followed by 30-day oral administration of HAMPT (33.5-134 mg/kg) to the mice inoculated with cancer cells produced significant inhibition on cancer metastasis dose-dependently without marked side effects. Fifty-day rat toxicity study with HAMPT at doses (335-1340 mg/kg) 20-fold higher than its therapeutic dose produced no significant toxicity. Interestingly, the acute toxic death could not be reached at the maximum administrable dose (5 g/kg). This proof-of-concept study provides the first conceptual evidence that cancer metastasis can be controlled by using affordable old drugs to restrain circulating tumor cells from gemmating on the metastatic soil without the need for cytotoxicity.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Melanoma/tratamento farmacológico , Animais , Aspirina/administração & dosagem , Doxiciclina/administração & dosagem , Interações Medicamentosas , Feminino , Células Endoteliais da Veia Umbilical Humana , Humanos , Lisina/administração & dosagem , Masculino , Melanoma/patologia , Melanoma Experimental/tratamento farmacológico , Camundongos , Camundongos Endogâmicos C57BL , Mifepristona/administração & dosagem , Metástase Neoplásica , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley
5.
AAPS J ; 16(2): 289-98, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24442753

RESUMO

Mifepristone (RU486) is marketed and used widely by women as an abortifacient, and experimentally for psychotic depression and anticancer treatments. After administration, metapristone is found to be the most predominant metabolite of mifepristone. We hypothesized that adhesion of circulating tumor cells (CTCs) to vascular endothelial bed is a crucial starting point in metastatic cascade, and that metapristone can serve as a cancer metastatic chemopreventive agent that can interrupt adhesion and invasion of CTCs to the intima of microvasculature. In the present study, we modified the synthesis procedure to produce grams of metapristone, fully characterized its spectral properties and in vitro cellular activities, including its cytostatic effects, cell cycle arrest, mitochondrial membrane potential, and apoptosis on human colorectal cancer HT-29 cells. Metapristone concentration dependently interrupted adhesion of HT-29 cells to endothelial cells. Metapristone may potentially be a useful agent to interrupt metastatic initiation.


Assuntos
Anticarcinógenos/síntese química , Mifepristona/análogos & derivados , Mifepristona/química , Metástase Neoplásica/prevenção & controle , Anexina A5/metabolismo , Anticarcinógenos/química , Anticarcinógenos/farmacologia , Caspase 3/metabolismo , Adesão Celular/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Cromatografia Líquida , Humanos , Técnicas In Vitro , Espectroscopia de Ressonância Magnética , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mifepristona/síntese química , Mifepristona/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier
6.
J Hazard Mater ; 184(1-3): 864-868, 2010 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-20810213

RESUMO

ZnO/Zn(2)TiO(4) core/shell nanowires were synthesized for the first time based on a solid-solid reaction of ZnO nanowires with a conformal shell of TiO(2), which was deposited by a sol-gel method. The as-prepared samples were characterized by X-ray diffraction (XRD) analysis, transmission electron microscope (TEM) and environmental scanning electron microscope (ESEM). The surface photovoltage (SPV) spectra indicated that the as-synthesized ZnO/Zn(2)TiO(4) core/shell nanowires exhibited more excellent photovoltaic activity than single ZnO nanowires. The enhanced photocatalytic activity of the ZnO/Zn(2)TiO(4) core/shell nanowires was demonstrated by the degradation of acetone under UV light irradiation. As monitored by the in situ FTIR, a sequence of chemical steps could be extracted during the photocatalytic oxidation of gaseous acetone, which was firstly degraded into formate, and subsequently converted into CO and CO(2). CO(2) was partially converted to carbonate further.


Assuntos
Acetona/química , Nanofios , Fotoquímica , Titânio/química , Óxido de Zinco/síntese química , Catálise , Microscopia Eletrônica de Varredura , Oxirredução , Espectroscopia de Infravermelho com Transformada de Fourier , Raios Ultravioleta , Difração de Raios X
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