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1.
Bioconjug Chem ; 30(3): 703-713, 2019 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-30582799

RESUMO

Hepatocellular carcinoma (HCC) is the sixth most common cancer worldwide with poor prognosis and limited options for treatment. Life expectancy after diagnosis is short; the currently available treatments are not well tolerated and have limited clinical benefit. There is a clear unmet clinical need for the development of new treatments. In this study, ultrasmall, 2 nm gold core nanoparticles (MidaCore) conjugated with the potent maytansine analogue DM1 (MTC-100038) were assessed as a systemic nanomedicine for the treatment of hepatocellular carcinoma. The platform improved overall tolerability of DM1, permitting ∼3-fold higher levels of drug to be administered compared to free drug. Dose for dose, MTC-100038 also facilitated delivery of ∼2.0-fold higher ( p = 0.039) levels of DM1 to the tumor compared to free DM1. MTC-100038 produced significant efficacy (tumor growth index ∼102%; p = <0.0001), in several murine xenograft models of HCC, and was superior to both free DM1 and the current standard of care, sorafenib. Furthermore, MTC-100038 displayed potent (nM) in vitro activity in various HCC primary patient derived cell lines and across various other different cancer cell types. These data demonstrate the potential of MidaCore nanoparticles to enhance tumor delivery of cytotoxic drugs and indicate MTC-100038 is worthy of further investigation as a potential treatment for HCC and other cancer types.


Assuntos
Antineoplásicos Fitogênicos/administração & dosagem , Carcinoma Hepatocelular/tratamento farmacológico , Ouro/química , Neoplasias Hepáticas/tratamento farmacológico , Maitansina/administração & dosagem , Nanopartículas Metálicas/química , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacocinética , Linhagem Celular Tumoral , Modelos Animais de Doenças , Portadores de Fármacos , Feminino , Humanos , Maitansina/análogos & derivados , Nanopartículas Metálicas/toxicidade , Camundongos , Camundongos Endogâmicos BALB C , Tamanho da Partícula , Ensaios Antitumorais Modelo de Xenoenxerto
2.
Indian J Palliat Care ; 20(3): 182-7, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25191003

RESUMO

AIM: To compare the efficacy and safety of oral transmucosal fentanyl citrate (OTFC) and oral morphine in Indian patients with breakthrough episodes of cancer pain. MATERIALS AND METHODS: In this randomized, open label, active controlled, clinical study, total 186 patients who regularly experienced 1-4 episodes of breakthrough cancer pain (BTCP) daily, over the persistent pain controlled by taking oral morphine 60 mg/day or its equivalent were randomized to receive either OTFC 200 mcg or oral morphine 10 mg for the treatment of BTCP for 3 days. Improvement in pain as determined by numerical rating scale (NRS) at 5, 15, 30, and 60 minutes of drug administration and percentage of BTCP episodes showing reduction in pain intensity by >33% at 15 minutes were primary efficacy endpoints. Secondary efficacy endpoints were requirement for rescue analgesia and global assessment by physician and patient. Data of both treatment groups were analysed by appropriate statistical test using software, STATISTICA, version 11. RESULTS: Patients treated with OTFC experienced significantly greater improvement in pain intensity of breakthrough episodes compared to those treated with oral morphine at all assessment time points (P < 0.0001). 56% of breakthrough pain episodes treated with OTFC showed a greater than 33% reduction in pain intensity from baseline at 15 minutes compared to 39% episodes treated with oral morphine (P < 0.0001). Patient's and physician's global assessment favoured OTFC than oral morphine (P < 0.0001). Requirement of rescue analgesia in both the study groups was similar (P > 0.05). Both study drugs were well tolerated. CONCLUSIONS: OTFC was found to provide faster onset of analgesic effect than immediate release oral morphine in management of breakthrough cancer pain.

3.
Biomed Chromatogr ; 26(12): 1559-66, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22454297

RESUMO

3',4',5'-Trimethoxyflavonol (TMFol) is a synthetic flavonol with preclinical cancer chemopreventive properties. The hypothesis was tested that, in mice, p.o. administration of TMFol results in measureable levels of the parent in target tissues. A single oral dose (240 mg/kg) was administered to mice (n = 4 per time point) with time points ranging from 5 to 1440 min. TMFol and its metabolites were identified and quantitated in all tissues by high-performance liquid chromatography (HPLC). Plasma levels of TMFol were at the limit of quantification or below, although metabolites were identified. Peak levels of TMFol in the gastrointestinal tract and the prostate averaged 1671 ± 265 µg/g (5.3 µmol/g) and 6.0 ± 1.6 µg/g (18.4 nmol/g), and occurred 20 and 360 min post-dose, respectively. The area under the tissue concentration-time curve (AUC) for TMFol was greater than those of the metabolites, indicating that TMFol is relatively metabolically stable. Micromolar TMFol levels are easily achieved in the prostate and gastrointestinal tract, suggesting that TMFol might exert chemopreventive efficacy at these tissue sites. Further investigations are warranted to elucidate the potential chemopreventive potency of TMFol.


Assuntos
Anticarcinógenos/metabolismo , Anticarcinógenos/farmacocinética , Flavonóis/metabolismo , Flavonóis/farmacocinética , Animais , Anticarcinógenos/análise , Anticarcinógenos/química , Cromatografia Líquida de Alta Pressão/métodos , Feminino , Flavonoides/análise , Flavonoides/química , Flavonoides/metabolismo , Flavonoides/farmacocinética , Flavonóis/análise , Flavonóis/química , Mucosa Intestinal/química , Mucosa Intestinal/metabolismo , Fígado/metabolismo , Masculino , Redes e Vias Metabólicas , Camundongos , Camundongos Endogâmicos C57BL , Sensibilidade e Especificidade , Distribuição Tecidual
4.
Cancer Epidemiol Biomarkers Prev ; 16(6): 1246-52, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17548692

RESUMO

The red grape constituent resveratrol possesses cancer chemopreventive properties in rodents. The hypothesis was tested that, in healthy humans, p.o. administration of resveratrol is safe and results in measurable plasma levels of resveratrol. A phase I study of oral resveratrol (single doses of 0.5, 1, 2.5, or 5 g) was conducted in 10 healthy volunteers per dose level. Resveratrol and its metabolites were identified in plasma and urine by high-performance liquid chromatography-tandem mass spectrometry and quantitated by high-performance liquid chromatography-UV. Consumption of resveratrol did not cause serious adverse events. Resveratrol and six metabolites were recovered from plasma and urine. Peak plasma levels of resveratrol at the highest dose were 539 +/- 384 ng/mL (2.4 micromol/L, mean +/- SD; n = 10), which occurred 1.5 h post-dose. Peak levels of two monoglucuronides and resveratrol-3-sulfate were 3- to 8-fold higher. The area under the plasma concentration curve (AUC) values for resveratrol-3-sulfate and resveratrol monoglucuronides were up to 23 times greater than those of resveratrol. Urinary excretion of resveratrol and its metabolites was rapid, with 77% of all urinary agent-derived species excreted within 4 h after the lowest dose. Cancer chemopreventive effects of resveratrol in cells in vitro require levels of at least 5 micromol/L. The results presented here intimate that consumption of high-dose resveratrol might be insufficient to elicit systemic levels commensurate with cancer chemopreventive efficacy. However, the high systemic levels of resveratrol conjugate metabolites suggest that their cancer chemopreventive properties warrant investigation.


Assuntos
Anticarcinógenos/farmacocinética , Estilbenos/farmacocinética , Adulto , Anticarcinógenos/metabolismo , Área Sob a Curva , Cromatografia Líquida de Alta Pressão , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/prevenção & controle , Resveratrol , Estilbenos/metabolismo , Espectrometria de Massas em Tandem
5.
Artigo em Inglês | MEDLINE | ID: mdl-17097357

RESUMO

We describe a reversed-phase HPLC method that uses gradient elution and UV detection (325 nm) to determine levels of resveratrol and identify six major conjugated metabolites in the plasma and urine of human volunteers after administration of a single oral dose of 1g. Waters Atlantis C18 3 microm served as the stationary phase. The gradient was formed using ammonium acetate and methanol, containing 2% propan-2-ol. Detection is linear between 5 ng/mL and 500 ng/mL in plasma (5-1000 ng/mL in urine). The coefficient of variation for intra- and inter-day variation is <10%. The average recovery of resveratrol from plasma and urine is 58+/-3%. The data presented in this report demonstrate a rapid, sensitive and accurate method for the analysis of resveratrol and its metabolites in human plasma and urine for pharmacokinetic studies.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Estilbenos/sangue , Estilbenos/urina , Inibidores da Angiogênese/sangue , Inibidores da Angiogênese/farmacocinética , Inibidores da Angiogênese/urina , Humanos , Reprodutibilidade dos Testes , Resveratrol , Espectrofotometria Ultravioleta , Estilbenos/farmacocinética
6.
J Clin Diagn Res ; 9(12): FC11-3, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26816910

RESUMO

INTRODUCTION: Different topical formulations of diclofenac have varying skin penetration profile. Recent advances in science and technology has led to the development of many new formulations of drugs for topical drug delivery. One such technological development has led to the innovation of Dynapar QPS, a novel, non-aqueous, quick penetrating solution (QPS) of diclofenac diethylamine. AIM: This study was aimed to measure the total exposure from the drug penetrating the skin in healthy human subjects and comparing the relative systemic bioavailability of Dynapar QPS(®) with diclofenac emulgel. MATERIALS AND METHODS: A 200 mg of diclofenac from either Dynapar QPS(®) (5 ml) or emulgel (20 g) was applied on back of subject as per the randomisation schedule. Blood samples were collected up to 16 hours post drug application. Plasma concentration of diclofenac was measured by pre-validated HPLC method. Pharmacokinetic (PK) parameters like Cmax, Tmax, t1/2, AUC0-t, AUC0-∞, and Kel, of diclofenac were determined for both the formulations. RESULTS: Mean Cmax after administration of Dynapar QPS(®) and diclofenac emulgel were 175.93 and 40.04 ng/ml, respectively. Tmax of diclofenac was almost half with QPS compared to emulgel (5.24 hrs versus 9.53 hrs respectively). The mean AUC0-t and AUC0-∞ after administration of Dynapar QPS(®) was higher as compared to diclofenac emulgel (AUC0-t: 1224.19 versus 289.78 ng.h/ml, respectively; AUC0-∞: 1718.21 versus 513.83 ng.h/ml, respectively). None of the subject experienced any adverse event during the study. CONCLUSION: The results indicate an enhanced penetration and subsequent absorption of diclofenac from Dynapar QPS(®) as compared to diclofenac emulgel. Higher penetration is likely to translate into better pain relief in patients.

7.
Autophagy ; 10(3): 524-5, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24419144

RESUMO

Resveratrol has many proposed health benefits, including the prevention of cancers, but its low bioavailability is considered a limiting factor in translating these effects to humans. Based on in vivo and clinical studies we have shown that resveratrol is indeed rapidly metabolized by phase II enzymes, and that resveratrol sulfates are deconjugated by steroid sulfatases to afford free resveratrol in vitro and in vivo and hence act as an intracellular reservoir for resveratrol. Further, we have demonstrated that at clinically achievable concentrations of resveratrol sulfate, parent resveratrol is regenerated within human colorectal cancer, but not normal epithelial cells, and is responsible for inducing autophagy with senescence selectively in cancer cells.


Assuntos
Anticarcinógenos/farmacologia , Autofagia/efeitos dos fármacos , Neoplasias Colorretais/patologia , Estilbenos/farmacologia , Sulfatos/farmacologia , Animais , Linhagem Celular Tumoral , Neoplasias Colorretais/tratamento farmacológico , Humanos , Espaço Intracelular/efeitos dos fármacos , Resveratrol
8.
J Clin Diagn Res ; 8(11): LC11-5, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25584252

RESUMO

BACKGROUND: Paracetamol is recommended as first line agent for pain management in osteoarthritis (OA) by various guidelines. The main problem associated with management of osteoarthritis is long term patient compliance to paracetamol due to its frequent dosing. OBJECTIVE: To evaluate the efficacy and safety of Paracetamol 650 mg dual release tablet twice daily (PCM 650 dual release) compared to paracetamol 500mg immediate release tablet thrice daily (PCM 500 IR) in the treatment of Knee OA. MATERIALS AND METHODS: In this randomized, open label, parallel, active controlled clinical study, 250 patients of OA knee meeting inclusion criteria were randomized to receive either PCM 650 dual release two times daily or PCM 500 IR three times daily for 6 weeks. Patients were assessed at baseline, 2, 4 and 6 weeks. Primary efficacy measures were severity of pain (Visual Analogue Scale) and Knee injury and osteoarthritis outcome score (KOOS) subscale for pain at week 2, 4 and 6. Other KOOS subscales (symptoms other than pain, function in daily living, function in sport and recreation, quality of life) and patient's and physicians global assessment of therapy were included as secondary endpoints. RESULTS: Both treatment groups showed improvement in primary endpoints at each evaluation visit. Patients receiving PCM 650 dual release showed significant improvement of pain in both primary endpoints at each study visit compared to patients receiving PCM 500 IR (p<0.001). PCM 650 dual release was significantly superior to PCM 500 IR for improvement in all KOOS subscales at each study visit (p<0.01). Less number of patients required additional rescue analgesics in PCM 650 dual release group (16% patients vs 26%, PCM 500 IR; p>0.05). Adverse effects were significantly less in PCM 650 dual release group (6% vs. 14% in PCM 500 IR; p<0.05). Patient's and physician's global assessment of therapy favoured PCM 650 dual release than PCM 500 IR (p<0.001). CONCLUSION: Patients with symptomatic OA of the knee showed a greater improvement in pain and functional capacity with PCM 650 dual release than PCM 500 IR with better tolerability.

9.
Sci Transl Med ; 5(205): 205ra133, 2013 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-24089405

RESUMO

The phytochemical resveratrol has been shown to exert numerous health benefits in preclinical studies, but its rapid metabolism and resulting poor bioavailability may limit translation of these effects to humans. Resveratrol metabolites might contribute to in vivo activity through regeneration of the parent compound. We present quantitation of sulfate and glucuronide conjugates of resveratrol in human plasma and tissue after repeated ingestion of resveratrol by volunteers and cancer patients, respectively. Subsequent pharmacokinetic characterization of a mixture of resveratrol-3-O-sulfate and resveratrol-4'-O-sulfate in mice showed that these metabolites are absorbed orally but have low bioavailabilities of ~14 and 3%, respectively. Sulfate hydrolysis in vivo liberated free resveratrol, which accounted for ~2% of the total resveratrol species present in mouse plasma. Monosulfate metabolites were also converted to the parent in human colorectal cells. The extent of cellular uptake was dependent on specific membrane transporters and dictated antiproliferative activity. Sulfate metabolites induced autophagy and senescence in human cancer cells; these effects were abrogated by inclusion of a sulfatase inhibitor, which reduced intracellular resveratrol. Together, our findings suggest that resveratrol is delivered to target tissues in a stable sulfate-conjugated form and that the parent compound is gradually regenerated in selected cells and may give rise to the beneficial effects in vivo. At doses considered to be safe in humans, resveratrol generated via this route may be of greater importance than the unmetabolized form.


Assuntos
Autofagia , Senescência Celular , Espaço Intracelular/metabolismo , Estilbenos/metabolismo , Sulfatos/metabolismo , Animais , Autofagia/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células , Senescência Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Neoplasias Colorretais/sangue , Glucuronídeos/sangue , Humanos , Espaço Intracelular/efeitos dos fármacos , Proteínas de Membrana Transportadoras/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Resveratrol , Estilbenos/sangue , Estilbenos/farmacologia
10.
Ann N Y Acad Sci ; 1215: 161-9, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21261655

RESUMO

An expanding body of preclinical evidence suggests resveratrol has the potential to impact a variety of human diseases. To translate encouraging experimental findings into human benefits, information is first needed on the safety, pharmacokinetics, pharmacodynamics, and, ultimately, clinical efficacy of resveratrol. Published clinical trials have largely focused on characterizing the pharmacokinetics and metabolism of resveratrol. Recent studies have also evaluated safety and potential mechanisms of activity following multiple dosing, and have found resveratrol to be safe and reasonably well-tolerated at doses of up to 5 g/day. However, the occurrence of mild to moderate side effects is likely to limit the doses employed in future trials to significantly less than this amount. This review describes the available clinical data, outlines how it supports the continuing development of resveratrol, and suggests what additional information is needed to increase the chances of success in future clinical trials.


Assuntos
Ensaios Clínicos como Assunto/métodos , Estilbenos/farmacocinética , Estilbenos/uso terapêutico , Animais , Ensaios Clínicos como Assunto/tendências , Humanos , Resveratrol
11.
Cancer Res ; 70(22): 9003-11, 2010 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-20935227

RESUMO

Resveratrol, a naturally occurring polyphenol, has cancer chemopreventive properties in preclinical models. It has been shown to downregulate the levels of insulin-like growth factor-1 (IGF-I) in rodents. The purpose of the study was to assess its safety, pharmacokinetics, and effects on circulating levels of IGF-I and IGF-binding protein-3 (IGFBP-3) after repeated dosing. Forty healthy volunteers ingested resveratrol at 0.5, 1.0, 2.5, or 5.0 g daily for 29 days. Levels of resveratrol and its metabolites were measured by high performance liquid chromatography-UV in plasma obtained before and up to 24 hours after a dose between days 21 and 28. IGF-I and IGFBP-3 were measured by ELISA in plasma taken predosing and on day 29. Resveratrol was safe, but the 2.5 and 5 g doses caused mild to moderate gastrointestinal symptoms. Resveratrol-3-O-sulfate, resveratrol-4'-O-glucuronide, and resveratrol-3-O-glucuronide were major plasma metabolites. Maximal plasma levels and areas under the concentration versus time curve for the metabolites dramatically exceeded those for resveratrol, in the case of areas under the concentration versus time curve, by up to 20.3-fold. Compared with predosing values, the ingestion of resveratrol caused a decrease in circulating IGF-I and IGFBP-3 (P<0.04 for both), respectively, in all volunteers. The decrease was most marked at the 2.5 g dose level. The results suggest that repeated administration of high doses of resveratrol generates micromolar concentrations of parent and much higher levels of glucuronide and sulfate conjugates in the plasma. The observed decrease in circulating IGF-I and IGFBP-3 might contribute to cancer chemopreventive activity.


Assuntos
Antineoplásicos Fitogênicos/farmacocinética , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Fator de Crescimento Insulin-Like I/metabolismo , Estilbenos/farmacocinética , Dor Abdominal/induzido quimicamente , Adulto , Antineoplásicos Fitogênicos/efeitos adversos , Antineoplásicos Fitogênicos/metabolismo , Área Sob a Curva , Cromatografia Líquida de Alta Pressão , Diarreia/induzido quimicamente , Relação Dose-Resposta a Droga , Ensaio de Imunoadsorção Enzimática , Glucuronídeos/sangue , Glucuronídeos/metabolismo , Humanos , Taxa de Depuração Metabólica , Pessoa de Meia-Idade , Náusea/induzido quimicamente , Resveratrol , Estilbenos/efeitos adversos , Estilbenos/sangue , Estilbenos/metabolismo , Adulto Jovem
12.
Cancer Res ; 70(19): 7392-9, 2010 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-20841478

RESUMO

Resveratrol is a phytochemical with chemopreventive activity in preclinical rodent models of colorectal carcinogenesis. Antiproliferation is one of the many chemopreventive modes of action it has been shown to engage in. Concentrations of resveratrol, which can be achieved in human tissues after p.o. administration, have not yet been defined. The purpose of this study was to measure concentrations of resveratrol and its metabolites in the colorectal tissue of humans who ingested resveratrol. Twenty patients with histologically confirmed colorectal cancer consumed eight daily doses of resveratrol at 0.5 or 1.0 g before surgical resection. Resveratrol was found to be well tolerated. Normal and malignant biopsy tissue samples were obtained before dosing. Parent compound plus its metabolites resveratrol-3-O-glucuronide, resveratrol-4'-O-glucuronide, resveratrol-3-O-sulfate, resveratrol-4'-O-sulfate, resveratrol sulfate glucuronide, and resveratrol disulfate were identified by high-performance liquid chromatography (HPLC) with UV or mass spectrometric detection in colorectal resection tissue. Quantitation was achieved by HPLC/UV. Cell proliferation, as reflected by Ki-67 staining, was compared in preintervention and postintervention tissue samples. Resveratrol and resveratrol-3-O-glucuronide were recovered from tissues at maximal mean concentrations of 674 and 86.0 nmol/g, respectively. Levels of resveratrol and its metabolites were consistently higher in tissues originating in the right side of the colon compared with the left. Consumption of resveratrol reduced tumor cell proliferation by 5% (P = 0.05). The results suggest that daily p.o. doses of resveratrol at 0.5 or 1.0 g produce levels in the human gastrointestinal tract of an order of magnitude sufficient to elicit anticarcinogenic effects. Resveratrol merits further clinical evaluation as a potential colorectal cancer chemopreventive agent.


Assuntos
Adenocarcinoma/tratamento farmacológico , Antineoplásicos Fitogênicos/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Estilbenos/uso terapêutico , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Adenocarcinoma/cirurgia , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos Fitogênicos/efeitos adversos , Antineoplásicos Fitogênicos/farmacocinética , Processos de Crescimento Celular/efeitos dos fármacos , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Neoplasias Colorretais/cirurgia , Terapia Combinada , Feminino , Humanos , Imuno-Histoquímica , Antígeno Ki-67/metabolismo , Masculino , Pessoa de Meia-Idade , Resveratrol , Estilbenos/efeitos adversos , Estilbenos/farmacocinética
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