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1.
J Nutr ; 153(7): 1866-1876, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37127137

RESUMO

BACKGROUND: Vitamin E (vit E) is an essential nutrient that functions as a lipophilic antioxidant and is used clinically to treat nonalcoholic fatty liver disease, where it suppresses oxidative damage and impedes the progression of steatosis and fibrosis. Mice lacking a critical liver iron-trafficking protein also manifest steatosis because of iron-mediated oxidative damage and are protected from liver disease by oral vit E supplements. OBJECTIVES: We aimed to examine the role of dietary vit E supplementation in modulating iron-sensing regulatory systems and nonheme iron levels in mouse liver. METHODS: C57Bl/6 male mice, aged 6 wk, were fed purified diets containing normal amounts of iron and either control (45 mg/kg) or elevated (450 mg/kg) levels of 2R-α-tocopherol (vit E) for 18 d. Mouse plasma and liver were analyzed for nonheme iron, levels and activity of iron homeostatic proteins, and markers of oxidative stress. We compared means ± SD for iron and oxidative stress parameters between mice fed the control diet and those fed the vit E diet. RESULTS: The Vit E-fed mice exhibited lower levels of liver nonheme iron (38% reduction, P < 0.0001) and ferritin (74% reduction, P < 0.01) than control-fed mice. The levels of liver mRNA for transferrin receptor 1 and divalent metal transporter 1 were reduced to 42% and 57% of the control, respectively. The mRNA levels for targets of nuclear factor erythroid 2-related factor (Nrf2), a major regulator of the oxidative stress response and iron-responsive genes, were also suppressed in vit E livers. Hepcidin, an iron regulatory hormone, levels were lower in the plasma (P < 0.05), and ferroportin (FPN), the iron exporter regulated by hepcidin, was expressed at higher levels in the liver (P < 0.05). CONCLUSIONS: Oral vit E supplementation in mice can lead to depletion of liver iron stores by suppressing the iron- and redox-sensing transcription factor Nrf2, leading to enhanced iron efflux through liver FPN. Iron depletion may indirectly enhance the antioxidative effects of vit E.


Assuntos
Ferro , Vitamina E , Camundongos , Masculino , Animais , Ferro/metabolismo , Vitamina E/farmacologia , Hepcidinas , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Fator 2 Relacionado a NF-E2/farmacologia , Fígado/metabolismo , Antioxidantes/metabolismo , RNA Mensageiro/genética , Camundongos Endogâmicos C57BL
2.
Surgery ; 172(2): 670-676, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35606184

RESUMO

BACKGROUND: Perioperative nutritional supplementation may improve outcomes. Trials have not investigated the role of combination strategy using different types of nutritional supplements. METHODS: We conducted a single-site randomized pilot trial, among gastrointestinal cancer patients undergoing surgery, comparing perioperative nutritional supplements versus placebo (1 placebo to each supplement), to determine feasibility of a larger trial. Intervention, administered in sequence, included: protein supplementation (preoperative day 30-6), protein supplementation rich in arginine and omega-6 (preoperative day 5-1, and postoperative day 1-5), and carbohydrate loading (surgery day). Primary outcome was enrollment. Secondary outcomes included participant compliance with study supplements (target ≥70% of total packets). We planned protocol modifications to improve enrollment and compliance. Postoperative complications were described. RESULTS: Over 18 months, 495 patients were screened, 144 were deemed eligible, and 71 consented to participate, resulting in an enrollment fraction of 71/144 (49%, 95% confidence interval: 41%-57%). 'Too much burden' was the most common reason for refusal to participate (34%). Participants' median overall compliance with study packets was 80%. Protocol modifications (decreasing the interval from enrollment to surgery from 4 to 2 weeks and decreasing length of baseline assessment) did not impact enrollment or compliance. Postoperative complications were similar between control (18/31 [58%, 95% confidence interval: 4-74]), and intervention (22/34 [65%, 95% confidence interval: 48-79]) arms, with a higher proportion of infectious complications in the control arm (16/31, 52% vs 12/34, 35%). CONCLUSION: Results from this pilot suggest a larger phase III trial is feasible. Postoperative infectious complications were common, making this a suitable outcome of interest.


Assuntos
Procedimentos Cirúrgicos do Sistema Digestório , Neoplasias , Suplementos Nutricionais , Estudos de Viabilidade , Humanos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle
3.
Life (Basel) ; 12(3)2022 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-35330204

RESUMO

Despite the widespread availability of effective vaccines, new cases of infection with severe acute respiratory syndrome coronavirus-2, the cause of coronavirus disease 2019 (COVID-19), remain a concern in the settings of vaccine hesitancy and vaccine breakthrough. In this randomized, controlled, phase 2 trial, we hypothesized that high-dose ascorbic acid delivered intravenously to achieve pharmacologic concentrations may target the high viral phase of COVID-19 and thus improve early clinical outcomes. Sixty-six patients admitted with COVID-19 and requiring supplemental oxygen were randomized to receive either escalating doses of intravenous ascorbic acid plus standard of care or standard of care alone. The demographic and clinical characteristics were well-balanced between the two study arms. The primary outcome evaluated in this study was clinical improvement at 72 h after randomization. While the primary outcome was not achieved, point estimates for the composite outcome and its individual components of decreased use of supplemental oxygen, decreased use of bronchodilators, and the time to discharge were all favorable for the treatment arm. Possible favorable effects of ascorbic acid were most apparent during the first 72 h of hospitalization, although these effects disappeared over the course of the entire hospitalization. Future larger trials of intravenous ascorbic acid should be based on our current understanding of COVID-19 with a focus on the potential early benefits of ascorbic in hospitalized patients.

4.
Clin Cancer Res ; 27(23): 6570-6579, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34615722

RESUMO

PURPOSE: Accurate IHC biomarkers incorporating nestin positivity or inositol polyphosphate-4-phosphate (INPP4B) loss have recently been optimized to identify the basal-like intrinsic breast cancer subtype regardless of estrogen, progesterone, or Her2 status. We examined the predictive capacity of these basal biomarkers in the CCTG MA.5 chemotherapy and MA.12 endocrine therapy trials. EXPERIMENTAL DESIGN: Formalin-fixed paraffin embedded blocks of primary tumors from patients randomized in the two trials were used to build tissue microarrays. IHC staining for nestin and INPP4B followed published methods and REMARK criteria. A prespecified statistical plan tested the hypothesis that patients with basal breast cancer (nestin+ or INPP4B-) would not benefit from anthracycline substitution in MA.5 or from tamoxifen in MA.12. RESULTS: Nestin positivity or INPP4B loss was observed in 110/453 (24%) interpretable samples from MA.5 and 47/366 (13%) from MA.12, and was associated with high grade, younger age, estrogen receptor negativity, triple-negative, core basal, and PAM50 basal-like subtypes. In the MA.5 trial, patients assigned as basal experienced lower benefit from anthracycline versus nonanthracycline adjuvant chemotherapy [HR, 1.49; 95% confidence interval (CI), 0.72-3.10] when compared with non-basal (nestin- and INPP4B+) cases where there was a higher benefit from anthracyclines (HR, 0.75; 95% CI, 0.54-1.04; P interaction = 0.01). In the MA.12 trial, patients assigned as basal did not demonstrate a benefit from adjuvant tamoxifen versus placebo (HR, 0.48; 95% CI, 0.12-1.86; P = 0.29), whereas nonbasal cases displayed significant benefit (HR, 0.66; 95% CI, 0.45-0.98; P = 0.04), although the interaction test was not significant. CONCLUSIONS: The nestin/INPP4B IHC panel identifies women with basal breast cancers who benefit from nonanthracycline chemotherapy but not endocrine adjuvant treatments.


Assuntos
Neoplasias da Mama , Biomarcadores Tumorais/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Canadá , Quimioterapia Adjuvante/métodos , Feminino , Humanos , Prognóstico , Receptor ErbB-2/uso terapêutico , Receptores de Estrogênio/genética
5.
Proc Natl Acad Sci U S A ; 117(3): 1666-1677, 2020 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-31911474

RESUMO

Major efforts are underway to identify agents that can potentiate effects of immune checkpoint inhibition. Here, we show that ascorbic acid (AA) treatment caused genomewide demethylation and enhanced expression of endogenous retroviral elements in lymphoma cells. AA also increased 5-hydroxymethylcytosine (5hmC) levels of CD8+ T cells and enhanced their cytotoxic activity in a lymphoma coculture system. High-dose AA treatment synergized with anti-PD1 therapy in a syngeneic lymphoma mouse model, resulting in marked inhibition of tumor growth compared with either agent alone. Analysis of the intratumoral epigenome revealed increased 5hmC with AA treatment, consistent with in vitro findings. Analysis of the tumor immune microenvironment revealed that AA strikingly increased intratumoral infiltration of CD8+ T cells and macrophages, suggesting enhanced tumor immune recognition. The combination treatment markedly enhanced intratumoral infiltration of macrophages and CD8+ T lymphocytes, granzyme B production by cytotoxic cells (cytotoxic T cells and natural killer cells), and interleukin 12 production by antigen-presenting cells compared with single-agent anti-PD1. These data indicate that AA potentiates anti-PD1 checkpoint inhibition through synergistic mechanisms. The study provides compelling rationale for testing combinations of high-dose AA and anti-PD1 agents in patients with aggressive B cell lymphoma as well as in preclinical models of other malignancies.


Assuntos
Anticorpos Monoclonais/farmacologia , Antineoplásicos/farmacologia , Ácido Ascórbico/administração & dosagem , Linfoma/tratamento farmacológico , 5-Metilcitosina/análogos & derivados , Animais , Antígeno B7-H1 , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Terapia Combinada , Modelos Animais de Doenças , Sinergismo Farmacológico , Feminino , Granzimas , Imunoterapia , Camundongos , Camundongos Endogâmicos BALB C , Receptor de Morte Celular Programada 1/efeitos dos fármacos , Receptor de Morte Celular Programada 1/metabolismo , Microambiente Tumoral/efeitos dos fármacos
6.
J Thromb Haemost ; 18(4): 905-915, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31995662

RESUMO

BACKGROUND: The Anticoagulation Therapy in Selected Cancer Patients at Risk of Recurrence of Venous Thromboembolism (SELECT-D) trial demonstrated reduction in recurrent venous thromboembolism (VTE) but increased bleeding with rivaroxaban compared with dalteparin for treatment of acute VTE in cancer patients, at 6 months. Uncertainty remains around optimal duration of anticoagulation. OBJECTIVES: To assess VTE recurrence and bleeding, with anticoagulation or not, beyond 6 months. PATIENTS/METHODS: In SELECT-D, after 6 months of trial treatment for VTE, patients with active cancer and residual deep vein thrombosis (RDVT) or index pulmonary embolism (PE) were eligible for randomization to a further 6 months of rivaroxaban or placebo. Patients with no RDVT stopped anticoagulation. Primary outcome was VTE recurrence at 12 months. The second randomization closed prematurely because of low recruitment when 92 of the planned 300 patients were recruited. RESULTS: Ninety-two of 136 eligible patients were randomized to rivaroxaban or placebo. The cumulative VTE recurrence after 6 months from the second randomization was 14% with placebo and 4% with rivaroxaban (hazard ratio, 0.32; 95% confidence interval [CI], 0.06-1.58). The major and clinically relevant non-major bleeding rates were 0% and 0% with placebo; and 5% (95% CI, 1-18) and 4% (95% CI, 1-17) with rivaroxaban. In an exploratory analysis, 7 (15%) of 46 placebo patients with RDVT or an index PE experienced recurrent VTE compared to none in the 35 patients in the RDVT-negative cohort (P = .03). CONCLUSION: The SELECT-D trial was underpowered to detect a statistically significant reduction in recurrent VTE with extended anticoagulation. The absence of RDVT and/or index PE, defined a population at low risk of recurrence.


Assuntos
Neoplasias , Tromboembolia Venosa , Anticoagulantes/efeitos adversos , Humanos , Neoplasias/complicações , Distribuição Aleatória , Rivaroxabana/efeitos adversos , Resultado do Tratamento , Tromboembolia Venosa/diagnóstico , Tromboembolia Venosa/tratamento farmacológico
7.
J Clin Oncol ; 36(20): 2017-2023, 2018 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-29746227

RESUMO

Purpose Venous thromboembolism (VTE) is common in patients with cancer. Long-term daily subcutaneous low molecular weight heparin has been standard treatment for such patients. The purpose of this study was to assess if an oral factor Xa inhibitor, rivaroxaban, would offer an alternative treatment for VTE in patients with cancer. Patient and Methods In this multicenter, randomized, open-label, pilot trial in the United Kingdom, patients with active cancer who had symptomatic pulmonary embolism (PE), incidental PE, or symptomatic lower-extremity proximal deep vein thrombosis (DVT) were recruited. Allocation was to dalteparin (200 IU/kg daily during month 1, then 150 IU/kg daily for months 2-6) or rivaroxaban (15 mg twice daily for 3 weeks, then 20 mg once daily for a total of 6 months). The primary outcome was VTE recurrence over 6 months. Safety was assessed by major bleeding and clinically relevant nonmajor bleeding (CRNMB). A sample size of 400 patients would provide estimates of VTE recurrence to within ± 4.5%, assuming a VTE recurrence rate at 6 months of 10%. Results A total of 203 patients were randomly assigned to each group, 58% of whom had metastases. Twenty-six patients experienced recurrent VTE (dalteparin, n = 18; rivaroxaban, n = 8). The 6-month cumulative VTE recurrence rate was 11% (95% CI, 7% to 16%) with dalteparin and 4% (95% CI, 2% to 9%) with rivaroxaban (hazard ratio [HR], 0.43; 95% CI, 0.19 to 0.99). The 6-month cumulative rate of major bleeding was 4% (95% CI, 2% to 8%) for dalteparin and 6% (95% CI, 3% to 11%) for rivaroxaban (HR, 1.83; 95% CI, 0.68 to 4.96). Corresponding rates of CRNMB were 4% (95% CI, 2% to 9%) and 13% (95% CI, 9% to 19%), respectively (HR, 3.76; 95% CI, 1.63 to 8.69). Conclusion Rivaroxaban was associated with relatively low VTE recurrence but higher CRNMB compared with dalteparin.


Assuntos
Inibidores do Fator Xa/uso terapêutico , Heparina de Baixo Peso Molecular/uso terapêutico , Neoplasias/sangue , Tromboembolia Venosa/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticoagulantes , Dalteparina/uso terapêutico , Feminino , Fibrinolíticos , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/patologia , Projetos Piloto , Rivaroxabana/uso terapêutico , Taxa de Sobrevida , Resultado do Tratamento
8.
Anticancer Drugs ; 29(4): 373-379, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29438178

RESUMO

Pancreatic ductal adenocarcinoma (PDA) has a dismal prognosis and is often discovered at an advanced stage with few therapeutic options. Current conventional regimens for PDA are associated with significant morbidity, decreased quality of life, and a considerable financial burden. As a result, some patients turn to integrative medicine therapies as an alternate option after a diagnosis of PDA. Intravenous pharmacologic ascorbic acid (PAA) is one such treatment. The use of PAA has been passionately debated for many years, but more recent rigorous scientific research has shown that there are significant blood concentration differences when ascorbic acid is given parenterally when compared to oral dosing. This pharmacologic difference appears to be critical for its role in oncology. Here, we report the use of PAA in a patient with poorly differentiated stage IV PDA as an exclusive chemotherapeutic regimen. The patient survived nearly 4 years after diagnosis, with PAA as his sole treatment, and he achieved objective regression of his disease. He died from sepsis and organ failure from a bowel perforation event. This case illustrates the possibility of PAA to effectively control tumor progression and serve as an adjunct to standard of care PDA chemotherapy regimens. Our patient's experience with PAA should be taken into consideration, along with previous research in cell, animal, and clinical experiments to design future treatment trials.


Assuntos
Ácido Ascórbico/uso terapêutico , Carcinoma Ductal Pancreático/tratamento farmacológico , Neoplasias Pancreáticas/tratamento farmacológico , Administração Intravenosa , Idoso , Ácido Ascórbico/administração & dosagem , Ácido Ascórbico/sangue , Procedimentos Cirúrgicos do Sistema Biliar/efeitos adversos , Carcinoma Ductal Pancreático/sangue , Carcinoma Ductal Pancreático/diagnóstico por imagem , Carcinoma Ductal Pancreático/cirurgia , Progressão da Doença , Humanos , Medicina Integrativa , Masculino , Neoplasias Pancreáticas/sangue , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/cirurgia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Prognóstico , Stents/efeitos adversos
9.
Sci Rep ; 7(1): 17188, 2017 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-29215048

RESUMO

Pancreatic cancer is among the most lethal cancers with poorly tolerated treatments. There is increasing interest in using high-dose intravenous ascorbate (IVC) in treating this disease partially because of its low toxicity. IVC bypasses bioavailability barriers of oral ingestion, provides pharmacological concentrations in tissues, and exhibits selective cytotoxic effects in cancer cells through peroxide formation. Here, we further revealed its anti-pancreatic cancer mechanisms and conducted a phase I/IIa study to investigate pharmacokinetic interaction between IVC and gemcitabine. Pharmacological ascorbate induced cell death in pancreatic cancer cells with diverse mutational backgrounds. Pharmacological ascorbate depleted cellular NAD+ preferentially in cancer cells versus normal cells, leading to depletion of ATP and robustly increased α-tubulin acetylation in cancer cells. While ATP depletion led to cell death, over-acetylated tubulin led to inhibition of motility and mitosis. Collagen was increased, and cancer cell epithelial-mesenchymal transition (EMT) was inhibited, accompanied with inhibition in metastasis. IVC was safe in patients and showed the possibility to prolong patient survival. There was no interference to gemcitabine pharmacokinetics by IVC administration. Taken together, these data revealed a multi-targeting mechanism of pharmacological ascorbate's anti-cancer action, with minimal toxicity, and provided guidance to design larger definitive trials testing efficacy of IVC in treating advanced pancreatic cancer.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Neoplasias Pancreáticas/tratamento farmacológico , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Ácido Ascórbico/administração & dosagem , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Feminino , Seguimentos , Humanos , Infusões Parenterais , Camundongos , Camundongos Nus , Metástase Neoplásica , Neoplasias Pancreáticas/patologia , Prognóstico , Estudos Prospectivos , Distribuição Tecidual , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto , Gencitabina
10.
J Natl Cancer Inst Monogr ; 2017(52)2017 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-29140484

RESUMO

In May 2016, the Office of Cancer Complementary and Alternative Medicine, Division of Cancer Diagnosis and Treatment, of the National Cancer Institute convened a special workshop focused on the State of the Science: Cancer Complementary and Alternative Medicine Therapeutics Research. The current state of the science, gaps, and future opportunities were reviewed and discussed by a distinguished panel of experts in this field of research, and the highlights of this meeting are reported herein.


Assuntos
Pesquisa Biomédica , Terapias Complementares , Oncologia , Pesquisa Biomédica/economia , Pesquisa Biomédica/métodos , Pesquisa Biomédica/normas , Pesquisa Biomédica/tendências , Terapias Complementares/normas , Terapias Complementares/tendências , Humanos , Oncologia/métodos , Oncologia/normas , Oncologia/tendências , Medicina de Precisão
12.
Free Radic Biol Med ; 95: 308-322, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27036367

RESUMO

We investigated the mechanism of selective ascorbate-induced cytotoxicity in tumor cells, including Hep G2 cells, compared to primary hepatocytes. H2O2 formation was required for ascorbate cytotoxicity, as extracellular catalase treatment protected tumor cells. H2O2 generated by glucose oxidase treatment also caused cell killing, but treatment with a pharmacologic dose (5-20mM) of ascorbate was significantly more cytotoxic at comparable rates of H2O2 production, suggesting that ascorbate enhanced H2O2 cytotoxicity. This was further supported by the finding that ascorbate at a non-cytotoxic dose (1mM) enhanced cell killing caused by glucose oxidase. Consistent with this conclusion, ascorbate treatment caused deregulation of cellular calcium homeostasis, resulting in massive mitochondrial calcium accumulation. Ascorbate acted synergistically with the chemotherapeutic sorafenib in killing Hep G2 cells, but not primary hepatocytes, suggesting adjuvant ascorbate treatment can broaden sorafenib's therapeutic range. Sorafenib caused mitochondrial depolarization and prevented mitochondrial calcium sequestration. Subsequent ascorbate addition further deregulated cellular calcium homeostasis promoting cell death. Additionally, we present the case of a patient with hepatocellular carcinoma (HCC) who had prolonged regression of a rib metastasis upon combination treatment with ascorbate and sorafenib, indicating that these studies have direct clinical relevance.


Assuntos
Ácido Ascórbico/administração & dosagem , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Niacinamida/análogos & derivados , Compostos de Fenilureia/administração & dosagem , Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Proliferação de Células/efeitos dos fármacos , Sinergismo Farmacológico , Células Hep G2 , Humanos , Peróxido de Hidrogênio/metabolismo , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Niacinamida/administração & dosagem , Sorafenibe
13.
Oncotarget ; 7(31): 49099-49106, 2016 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-27056899

RESUMO

Recent evidence demonstrated CIN4 as a predictive marker of anthracycline benefit in early breast cancer. An analysis of the NCIC CTG MA.21 clinical trial was performed to test the role of existing CIN gene expression signatures as prognostic and predictive markers in the context of taxane based chemotherapy.RNA was extracted from patients in cyclophosphamide, epirubicin and flurouracil (CEF) and epirubicin, cyclophosphamide and paclitaxel (EC/T) arms of the NCIC CTG MA.21 trial and analysed using NanoString technology.After multivariate analysis both high CIN25 and CIN70 score was significantly associated with an increased in RFS (HR 1.76, 95%CI 1.07-2.86, p=0.0018 and HR 1.59, 95%CI 1.12-2.25, p=0.0096 respectively). Patients whose tumours had low CIN4 gene expression scores were associated with an increase in RFS (HR: 0.64, 95% CI 0.39-1.03, p=0.06) when treated with EC/T compared to patients treated with CEF.In conclusion we have demonstrated CIN25 and CIN70 as prognostic markers in breast cancer and that CIN4 is a potential predictive maker of benefit from taxane treatment.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Instabilidade Cromossômica , Taxoides/química , Adulto , Idoso , Antraciclinas/uso terapêutico , Antibióticos Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/metabolismo , Quimioterapia Adjuvante , Ciclofosfamida/administração & dosagem , Intervalo Livre de Doença , Epirubicina/administração & dosagem , Feminino , Fluoruracila/administração & dosagem , Perfilação da Expressão Gênica , Humanos , Pessoa de Meia-Idade , Paclitaxel/administração & dosagem , Prognóstico
14.
Am J Physiol Regul Integr Comp Physiol ; 309(3): R223-34, 2015 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-25994956

RESUMO

Amphotericin B (Ampho B) isa fungicidal drug that causes cell wall injury. Pharmacological ascorbate induces the extracellular prooxidants, which might enter the Ampho B-induced cell wall porosity and act synergistically.W e tested low-dose Ampho B with a short course of pharmacological ascorbate using a mouse model of sepsis preconditioned with an injection of Candida albicans 6 h prior to cecal ligation and puncture (CLP). In this model, candidemia reappeared as early as 6 h after CLP with a predictably high mortality rate. This characteristic mimics sepsis in the phase of immunosuppression inpatients. Using the model, at 12- and 18-h post-CLP, we administered isotonic (pH neutralized) pharmacological ascorbate intravenously with low-dose Ampho B or sodium deoxycholate, vehicle-controlled, administered IP. The survival rate of low-dose Ampho B plus ascorbate was 53%, compared with < 11% for low-dose Ampho B or high-dose Ampho B alone. In addition, a beneficial effect was demonstrated in terms of kidney damage,liver injury, spleen histopathology, and serum markers at 24 h after CLP. Kidney injury was less severe in low-dose Ampho B plus ascorbate combination therapy due to less severe sepsis. Moreover, ascorbate enhanced the effectiveness of phagocytosis against C. albicans in human phagocytic cells. Taken together, the data indicate that the new mouse model simulates sepsis-induced immunosuppression and that the combination of pharmacological ascorbate with an antifungal drug is a potentially effective treatment that may reduce nephrotoxicity, and perhaps also increase fungicidal activity in patients with systemic candidiasis caused by Candida albicans.


Assuntos
Anfotericina B/farmacologia , Ácido Ascórbico/farmacologia , Candidemia/tratamento farmacológico , Rim/efeitos dos fármacos , Sepse/tratamento farmacológico , Anfotericina B/administração & dosagem , Animais , Ácido Ascórbico/administração & dosagem , Candidemia/complicações , Modelos Animais de Doenças , Combinação de Medicamentos , Fígado/efeitos dos fármacos , Masculino , Camundongos Endogâmicos BALB C , Sepse/etiologia , Baço/efeitos dos fármacos
15.
Breast Cancer Res Treat ; 150(3): 605-11, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25833209

RESUMO

Low vitamin D levels have been associated with poor breast cancer outcomes in observational studies. We examined the association of vitamin D blood levels with relapse-free survival (RFS), breast cancer-specific survival (BCSS), and overall survival (OS) in the MA.21 randomized clinical trial. Fasting blood was collected pre-chemotherapy in 934/2104 (44.4 %) of subjects; 25 hydroxy vitamin D was measured (radioimmunoassay, Diasorin) in one batch. Vitamin D was assessed as a transformed continuous factor, and categorically (quartiles and clinical classifications). Univariate and multivariate prognostic analyses (adjusted for treatment, stratification factors, and baseline imbalances) were performed using Cox models. Most patients were young (median 47.8 years), white (91.6 %) and premenopausal (69.4 %) with grade III (52 %), HER2 negative or missing (89.5 %), ER positive (61.9 %), T1-2 (89.4 %), N + (72.7 %) breast cancer. Compared to the full population, those with vitamin D levels were more likely to be white, PS 1 or 2, to have undergone mastectomy, and to have an ER + tumor. Mean vitamin D was 69.7 nmol/L (27.9 ng/ml) and did not vary by tumor subtype. The majority (80.5 %) had levels >50 nmol/L (20 ng/ml), considered adequate by Institute of Medicine. Continuous vitamin D was not multivariately associated with RFS, BCSS, or OS (p = 0.36, 0.26, 0.33, respectively); categorical vitamin D was also not associated with outcome. Vitamin D associations with RFS did not differ within ER/HER2 subgroups. There was no evidence that vitamin D blood level was associated with RFS, BCSS, and OS in MA.21; the majority of subjects had adequate vitamin D levels at study entry.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Vitamina D/análogos & derivados , Neoplasias da Mama/sangue , Neoplasias da Mama/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Análise de Sobrevida , Resultado do Tratamento , Vitamina D/sangue
16.
Bioconjug Chem ; 26(4): 625-32, 2015 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-25781873

RESUMO

There is a critical need to advance promising novel molecular imaging (MI) agents for cancer from preclinical studies to first-in-humans Phase I clinical trials in order to realize their full potential for cancer detection and for predicting or monitoring response to targeted ("personalized") cancer therapies. Steps to clinical translation include radiopharmaceutical formulation, preclinical pharmacology and toxicology studies, clinical trial design and human ethics approval, and regulatory agency submission. In this Topical Review, we provide a "roadmap" to advancing one class of novel MI agents to Phase I trials in academia and illustrate the processes that we have successfully applied for (111)In-labeled pertuzumab, a MI probe for monitoring response of HER2-positive breast cancer to treatment with trastuzumab (Herceptin). We hope that our experience will encourage other academic radiopharmaceutical scientists to embrace this challenge.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Antineoplásicos/uso terapêutico , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/tratamento farmacológico , Índio/química , Compostos Radiofarmacêuticos/química , Trastuzumab/uso terapêutico , Animais , Anticorpos Monoclonais Humanizados/metabolismo , Antineoplásicos/metabolismo , Neoplasias da Mama/metabolismo , Neoplasias da Mama/ultraestrutura , Ensaios Clínicos Fase I como Assunto , Aprovação de Drogas , Avaliação Pré-Clínica de Medicamentos , Feminino , Humanos , Índio/metabolismo , Imagem Molecular/métodos , Terapia de Alvo Molecular , Cintilografia , Compostos Radiofarmacêuticos/metabolismo , Kit de Reagentes para Diagnóstico , Receptor ErbB-2/antagonistas & inibidores , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Coloração e Rotulagem/métodos , Trastuzumab/metabolismo
18.
Sci Transl Med ; 6(222): 222ra18, 2014 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-24500406

RESUMO

Ascorbate (vitamin C) was an early, unorthodox therapy for cancer, with an outstanding safety profile and anecdotal clinical benefit. Because oral ascorbate was ineffective in two cancer clinical trials, ascorbate was abandoned by conventional oncology but continued to be used in complementary and alternative medicine. Recent studies provide rationale for reexamining ascorbate treatment. Because of marked pharmacokinetic differences, intravenous, but not oral, ascorbate produces millimolar concentrations both in blood and in tissues, killing cancer cells without harming normal tissues. In the interstitial fluid surrounding tumor cells, millimolar concentrations of ascorbate exert local pro-oxidant effects by mediating hydrogen peroxide (H(2)O(2)) formation, which kills cancer cells. We investigated downstream mechanisms of ascorbate-induced cell death. Data show that millimolar ascorbate, acting as a pro-oxidant, induced DNA damage and depleted cellular adenosine triphosphate (ATP), activated the ataxia telangiectasia mutated (ATM)/adenosine monophosphate-activated protein kinase (AMPK) pathway, and resulted in mammalian target of rapamycin (mTOR) inhibition and death in ovarian cancer cells. The combination of parenteral ascorbate with the conventional chemotherapeutic agents carboplatin and paclitaxel synergistically inhibited ovarian cancer in mouse models and reduced chemotherapy-associated toxicity in patients with ovarian cancer. On the basis of its potential benefit and minimal toxicity, examination of intravenous ascorbate in combination with standard chemotherapy is justified in larger clinical trials.


Assuntos
Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , Ácido Ascórbico/administração & dosagem , Ácido Ascórbico/uso terapêutico , Infusões Parenterais , Neoplasias Ovarianas/tratamento farmacológico , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Ácido Ascórbico/efeitos adversos , Carboplatina/farmacologia , Carboplatina/uso terapêutico , Morte Celular/efeitos dos fármacos , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Feminino , Camundongos , Neoplasias Ovarianas/patologia , Paclitaxel/farmacologia , Paclitaxel/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto
19.
J Clin Oncol ; 31(30): 3758-63, 2013 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-24043733

RESUMO

PURPOSE: Because of its morbidity and chronicity, arm lymphedema remains a concerning complication of breast cancer treatment. Although massage-based decongestive therapy is often recommended, randomized trials have not consistently demonstrated benefit over more conservative measures. PATIENTS AND METHODS: Women previously treated for breast cancer with lymphedema were enrolled from six institutions. Volumes were calculated from circumference measurements. Patients with a minimum of 10% volume difference between their arms were randomly assigned to either compression garments (control) or daily manual lymphatic drainage and bandaging followed by compression garments (experimental). The primary outcome was percent reduction in excess arm volume from baseline to 6 weeks. RESULTS: A total of 103 women were randomly assigned, and 95 were evaluable. Mean reduction of excess arm volume was 29.0% in the experimental group and 22.6% in the control group (difference, 6.4%; 95% CI, -6.8% to 20.5%; P = .34). Absolute volume loss was 250 mL and 143 mL in the experimental and control groups, respectively (difference, 107 mL; 95% CI, 13 to 203 mL; P = .03). There was no difference between groups in the proportion of patients losing 50% or greater excess arm volume. Quality of life (Short Form-36 Health Survey) and arm function were not different between groups. CONCLUSION: This trial was unable to demonstrate a significant improvement in lymphedema with decongestive therapy compared with a more conservative approach. The failure to detect a difference may have been a result of the relatively small size of our trial.


Assuntos
Neoplasias da Mama/terapia , Vestuário , Bandagens Compressivas , Linfedema/etiologia , Linfedema/terapia , Massagem , Extremidade Superior , Adulto , Idoso , Neoplasias da Mama/complicações , Fatores de Confusão Epidemiológicos , Drenagem , Feminino , Humanos , Pessoa de Meia-Idade , Qualidade de Vida , Resultado do Tratamento
20.
Antioxid Redox Signal ; 19(17): 2141-56, 2013 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-23621620

RESUMO

SIGNIFICANCE: Ewan Cameron reported that ascorbate, given orally and intravenously at doses of up to 10 g/day, was effective in the treatment of cancer. Double-blind placebo-controlled clinical trials showed no survival advantage when the same doses of ascorbate were given orally, leading the medical and scientific communities to dismiss the use of ascorbate as a potential cancer treatment. However, the route of administration results in major differences in ascorbate bioavailability. Tissue and plasma concentrations are tightly controlled in response to oral administration, but this can be bypassed by intravenous administration. These data provide a plausible scientific rationale for the absence of a response to orally administered ascorbate in the Mayo clinic trials and indicate the need to reassess ascorbate as a cancer therapeutic. RECENT ADVANCES: High dose ascorbate is selectively cytotoxic to cancer cell lines through the generation of extracellular hydrogen peroxide (H2O2). Murine xenograft models confirm a growth inhibitory effect of pharmacological concentrations. The safety of intravenous ascorbate has been verified in encouraging pilot clinical studies. CRITICAL ISSUES: Neither the selective toxicity of pharmacologic ascorbate against cancer cells nor the mechanism of H2O2-mediated cytotoxicity is fully understood. Despite promising preclinical data, the question of clinical efficacy remains. FUTURE DIRECTIONS: A full delineation of mechanism is of interest because it may indicate susceptible cancer types. Effects of pharmacologic ascorbate used in combination with standard treatments need to be defined. Most importantly, the clinical efficacy of ascorbate needs to be reassessed using proper dosing, route of administration, and controls.


Assuntos
Antineoplásicos/administração & dosagem , Ácido Ascórbico/administração & dosagem , Neoplasias/tratamento farmacológico , Administração Oral , Animais , Antineoplásicos/farmacocinética , Ácido Ascórbico/farmacocinética , Disponibilidade Biológica , Morte Celular/efeitos dos fármacos , Interações Medicamentosas , Ensaios de Seleção de Medicamentos Antitumorais , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Neoplasias/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais
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