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1.
Acta Oncol ; 59(10): 1186-1192, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32500780

RESUMEN

PURPOSE: Pelvic target dose from intensity-modulated proton therapy (IMPT) is sensitive to patient bowel motion. Robustly optimized plans in regard to bowel filling may improve the dose coverage in the treatment course. Our purpose is to investigate the effect of air volume in large and small bowel and rectum on target dose from IMPT plans. METHODS AND MATERIAL: Data from 17 cancer patients (11 prostate, 3 gynecologic, 2 colon, and 1 embryonal rhabdomyosarcoma) with planning CT (pCT) and weekly or biweekly scanned quality assurance CTs (QACTs; 82 QACT scans total) were studied. Air in bowels and rectum traversed by proton pencil beams was contoured. The robust treatment plan was made by using 3 CT sets: the pCT set and 2 virtual CT sets that were copies of pCT but in which the fillings of bowels and rectum were overridden to be either air or muscle. Each plan had 2-5 beams with a mean of 3 beams. Targets in the pCT were mapped to the QACTs by deformable image registration, and the dose in QACTs was calculated. Dose coverage (D99 and D95) and correlations between dose coverage and changes in air volume were analyzed. The significance of the correlation was analyzed by t test. RESULTS: Mean changes of D99 in QACTs were within 3% of those in the pCT for all prostate and colon cases but >3% in 2 of the 3 gynecologic cases and in the embryonal rhabdomyosarcoma case. Of these three cases with mean change of D99 > 3%, air volume may be the main cause in 2. For the prostate cases, correlation coefficients were <0.7 between change in air volume and change in D99 and D95, because other anatomy changes also contributed to dose deviation. Correlation coefficients in the non-prostate cases were >0.9 between D99 change and rectum and between D95 change and small bowel, indicating a greater effect of the air volume on target dose. CONCLUSION: The air volume may still have an important effect on target dose coverage in treatment plans using 3 CT sets, particularly when the air is traversed by multiple beams.


Asunto(s)
Aire , Intestino Grueso/fisiopatología , Neoplasias/radioterapia , Terapia de Protones , Radioterapia de Intensidad Modulada , Recto/fisiopatología , Humanos , Órganos en Riesgo , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador
2.
Pharm Res ; 34(12): 2698-2709, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28971289

RESUMEN

PURPOSE: Biomarkers serve a number of purposes during drug development including defining the natural history of injury/disease, serving as a secondary endpoint or trigger for intervention, and/or aiding in the selection of an effective dose in humans. BIO 300 is a patent-protected pharmaceutical formulation of nanoparticles of synthetic genistein being developed by Humanetics Corporation. The primary goal of this metabolomic discovery experiment was to identify biomarkers that correlate with radiation-induced lung injury and BIO 300 efficacy for mitigating tissue damage based upon the primary endpoint of survival. METHODS: High-throughput targeted metabolomics of lung tissue from male C57L/J mice exposed to 12.5 Gy whole thorax lung irradiation, treated daily with 400 mg/kg BIO 300 for either 2 weeks or 6 weeks starting 24 h post radiation exposure, were assayed at 180 d post-radiation to identify potential biomarkers. RESULTS: A panel of lung metabolites that are responsive to radiation and able to distinguish an efficacious treatment schedule of BIO 300 from a non-efficacious treatment schedule in terms of 180 d survival were identified. CONCLUSIONS: These metabolites represent potential biomarkers that could be further validated for use in drug development of BIO 300 and in the translation of dose from animal to human.


Asunto(s)
Genisteína/uso terapéutico , Lesión Pulmonar/tratamiento farmacológico , Pulmón/efectos de los fármacos , Pulmón/efectos de la radiación , Metabolómica/métodos , Traumatismos Experimentales por Radiación/tratamiento farmacológico , Protectores contra Radiación/uso terapéutico , Animales , Biomarcadores/análisis , Biomarcadores/metabolismo , Modelos Animales de Enfermedad , Genisteína/análogos & derivados , Genisteína/farmacología , Pulmón/metabolismo , Lesión Pulmonar/metabolismo , Masculino , Ratones Endogámicos C57BL , Traumatismos Experimentales por Radiación/metabolismo , Protectores contra Radiación/química , Protectores contra Radiación/farmacología
3.
Biomed Chromatogr ; 31(3)2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27557409

RESUMEN

Lipids represent biologically ubiquitous and highly dynamic molecules in terms of abundance and structural diversity. Whereas the potential for lipids to inform on disease/injury is promising, their unique characteristics make detection and identification of lipids from biological samples analytically demanding. We report the use of ultraperformance convergence chromatography (UPC2 ), a variant of supercritical fluid chromatography, coupled to high-resolution, data-independent tandem mass spectrometry for characterization of total lipid extracts from mouse lung tissue. The UPC2 platform resulted in lipid class separation and when combined with orthogonal column chemistries yielded chromatographic separation of intra-class species based on acyl chain hydrophobicity. Moreover, the combined approach of using UPC2 with orthogonal column chemistries, accurate mass measurements, time-aligned low- and high-collision energy total ion chromatograms, and positive and negative ion mode product ion spectra correlation allowed for confident lipid identification. Of great interest was the identification of differentially expressed ceramides that were elevated 24 h post whole thorax lung irradiation. The identification of lipids that were elevated 24 h post-irradiation signifies a unique opportunity to investigate early mechanisms of action prior to the onset of clinical symptoms in the whole thorax lung irradiation mouse model.


Asunto(s)
Biomarcadores/análisis , Lípidos/análisis , Espectrometría de Masas en Tándem/métodos , Animales , Ceramidas/análisis , Cromatografía Líquida de Alta Presión , Cromatografía con Fluido Supercrítico , Ratones
4.
Lab Invest ; 96(9): 936-49, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27479087

RESUMEN

Within this millennium there has been resurgence in funding and research dealing with animal models of radiation-induced lung injury to identify and establish predictive biomarkers and effective mitigating agents that are applicable to humans. Most have been performed on mice but there needs to be assurance that the emphasis on such models is not misplaced. We therefore considered it timely to perform a comprehensive appraisal of the literature dealing with radiation lung injury of mice and to critically evaluate the validity and clinical relevance of the research. A total of 357 research papers covering the period of 1970-2015 were extensively reviewed. Whole thorax irradiation (WTI) has become the most common treatment for studying lung injury in mice and distinct trends were seen with regard to the murine strain, radiation dose, intended pathology investigated, length of study, and assays. Recently, the C57BL/6 strain has been increasingly used in the majority of these studies with the notion that they are susceptible to pulmonary fibrosis. Nonetheless, many of these investigations depend on animal survival as the primary end point and neglect the importance of radiation pneumonitis and the anomaly of lethal pleural effusions. A relatively large variation in survival times of C5BL/6 mice is also seen among different institutions pointing to the need for standardization of radiation treatments and environmental conditions. An analysis of mitigating drug treatments is complicated by the fact that the majority of studies are limited to the C57BL/6 strain with a premature termination of the experiments and do not establish whether the treatment actually prevents or simply delays the progression of radiation injury. This survey of the literature has pointed to several improvements that need to be considered in establishing a reliable preclinical murine model of radiation lung injury. The lethality end point should also be used cautiously and with greater emphasis on other assays such as non-invasive lung functional and imaging monitoring in order to quantify specific pulmonary injury that can be better extrapolated to radiation toxicity encountered in our own species.


Asunto(s)
Modelos Animales de Enfermedad , Expresión Génica/efectos de la radiación , Pulmón/efectos de la radiación , Traumatismos por Radiación/metabolismo , Animales , Humanos , Pulmón/metabolismo , Pulmón/patología , Ratones Endogámicos C3H , Ratones Endogámicos C57BL , Ratones Endogámicos CBA , Traumatismos por Radiación/genética , Especificidad de la Especie , Encuestas y Cuestionarios
5.
Int J Hyperthermia ; 32(4): 398-406, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-27097528

RESUMEN

Hyperthermia represents a unique, safe, and advantageous methodology for improving therapeutic strategies in the management of bladder cancer. This modality has shown promise in contributing to treatment regimens for both superficial and muscle-invasive disease. Especially in conjunction with intravesical chemotherapy, systemic therapy, and radiotherapy, hyperthermia shows particular synergistic benefit. As such, it should be explored further through clinical use and clinical trial in conjunction with currently available techniques and emerging technologies. However, to conceptualise the way forward, it is particularly important to understand the current challenges to widespread use of non-invasive, bladder-sparing approaches and the current state of bladder cancer care. As such, in the following article, we have focused on not only the rationale for concurrent radiotherapy and hyperthermia, but also the clinical landscape in bladder cancer as a whole.


Asunto(s)
Hipertermia Inducida , Neoplasias de la Vejiga Urinaria/radioterapia , Neoplasias de la Vejiga Urinaria/terapia , Antineoplásicos/administración & dosificación , Antineoplásicos/uso terapéutico , Terapia Combinada , Humanos , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico
6.
Am J Pathol ; 182(4): 1248-54, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23395092

RESUMEN

Gastrin-releasing peptide (GRP), secreted by pulmonary neuroendocrine cells, mediates oxidant-induced lung injury in animal models. Considering that GRP blockade abrogates pulmonary inflammation and fibrosis in hyperoxic baboons, we hypothesized that ionizing radiation triggers GRP secretion, contributing to inflammatory and fibrotic phases of radiation-induced lung injury (RiLI). Using C57BL/6 mouse model of pulmonary fibrosis developing ≥20 weeks after high-dose thoracic radiation (15 Gy), we injected small molecule 77427 i.p. approximately 1 hour after radiation then twice weekly for up to 20 weeks. Sham controls were anesthetized and placed in the irradiator without radiation. Lung paraffin sections were immunostained and quantitative image analyses performed. Mice exposed to radiation plus PBS had increased interstitial CD68(+) macrophages 4 weeks after radiation and pulmonary neuroendocrine cells hyperplasia 6 weeks after radiation. Ten weeks later radiation plus PBS controls had significantly increased pSmad2/3(+) nuclei/cm(2). GRP blockade with 77427 treatment diminished CD68(+), GRP(+), and pSmad2/3(+) cells. Finally, interstitial fibrosis was evident 20 weeks after radiation by immunostaining for α-smooth muscle actin and collagen deposition. Treatment with 77427 abrogated interstitial α-smooth muscle actin and collagen. Sham mice given 77427 did not differ significantly from PBS controls. Our data are the first to show that GRP blockade decreases inflammatory and fibrotic responses to radiation in mice. GRP blockade is a novel radiation fibrosis mitigating agent that could be clinically useful in humans exposed to radiation therapeutically or unintentionally.


Asunto(s)
Péptido Liberador de Gastrina/antagonistas & inhibidores , Lesión Pulmonar/tratamiento farmacológico , Traumatismos por Radiación/tratamiento farmacológico , Animales , Recuento de Células , Colágeno/metabolismo , Péptido Liberador de Gastrina/metabolismo , Humanos , Pulmón/diagnóstico por imagen , Pulmón/efectos de los fármacos , Pulmón/patología , Lesión Pulmonar/etiología , Lesión Pulmonar/patología , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Macrófagos/patología , Ratones , Ratones Endogámicos C57BL , Modelos Biológicos , Células Neuroendocrinas/efectos de los fármacos , Células Neuroendocrinas/metabolismo , Células Neuroendocrinas/patología , Células Neuroendocrinas/efectos de la radiación , Pirimidinas/farmacología , Pirimidinas/uso terapéutico , Traumatismos por Radiación/complicaciones , Traumatismos por Radiación/patología , Radiografía , Proteínas Smad/metabolismo
7.
Int J Hyperthermia ; 30(3): 171-5, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24490762

RESUMEN

PURPOSE: This paper aims to evaluate the safety and heating efficiency of external deep pelvic hyperthermia combined with intravesical mitomycin C (MMC) as a novel therapy for non-muscle-invasive bladder cancer (NMIBC). MATERIALS AND METHODS: We enrolled subjects with bacillus Calmette-Guérin (BCG) refractory NMIBC to an early phase clinical trial of external deep pelvic hyperthermia (using a BSD-2000 device) combined with MMC. Bladders were heated to 42 °C for 1 h during intravesical MMC treatment. Treatments were given weekly for 6 weeks, then monthly for 4 months. Heating parameters, treatment toxicity, and clinical outcomes were systematically measured. RESULTS: Fifteen patients were enrolled on the clinical trial. Median age was 66 years and 87% were male. Median European Organisation for Research and Treatment of Cancer (EORTC) recurrence and progression scores were 6 and 8, respectively. The full treatment course was attained in 73% of subjects. Effective bladder heating was possible in all but one patient who could not tolerate the supine position due to lung disease. Adverse events were all minor (grade 2 or less) and no systemic toxicity was observed. The most common adverse effects were Foley catheter pain (40%), abdominal discomfort (33%), chemical cystitis symptoms (27%), and abdominal skin swelling (27%). With a median follow-up of 3.18 years, 67% experienced another bladder cancer recurrence (none were muscle invasive) and 13% experienced an upper tract recurrence. CONCLUSIONS: External deep pelvic hyperthermia using the BSD-2000 device is a safe and reproducible method of heating the bladder in patients undergoing intravesical MMC. The efficacy of this treatment modality should be explored further in clinical trials.


Asunto(s)
Hipertermia Inducida , Mitomicina/uso terapéutico , Pelvis , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mitomicina/administración & dosificación , Invasividad Neoplásica , Proyectos Piloto , Neoplasias de la Vejiga Urinaria/patología
8.
Int J Hyperthermia ; 30(3): 176-83, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24669804

RESUMEN

PURPOSE: The aim of this paper is to report thermal dosimetry characteristics of external deep regional pelvic hyperthermia combined with intravesical mitomycin C (MMC) for treating bladder cancer following transurethral resection of bladder tumour, and to use thermal data to evaluate reliability of delivering the prescribed hyperthermia dose to bladder tissue. MATERIALS AND METHODS: A total of 14 patients were treated with MMC and deep regional hyperthermia (BSD-2000, Sigma Ellipse or Sigma 60). The hyperthermia objective was 42° ± 2 °C to bladder tissue for ≥40 min per treatment. Temperatures were monitored with thermistor probes and recorded values were used to calculate thermal dose and evaluate treatment. Anatomical characteristics were examined for possible correlations with heating. RESULTS: Combined with BSD-2000 standard treatment planning and patient feedback, real-time temperature monitoring allowed thermal steering of heat sufficient to attain the prescribed thermal dose to bladder tissue within patient tolerance in 91.6% of treatments. Mean treatment time for bladder tissue >40 °C was 61.9 ± 11.4 min and mean thermal dose was 21.3 ± 16.5 CEM43. Average thermal doses obtained in normal tissues were 1.6 ± 1.2 CEM43 for the rectum and 0.8 ± 1.3 CEM43 in superficial normal tissues. No significant correlation was seen between patient anatomical characteristics and thermal dose achieved in bladder tissue. CONCLUSIONS: This study demonstrates that a hyperthermia prescription of 42° ± 2 °C for 40-60 min can be delivered safely to bladder tissue with external radiofrequency phased array applicators for a typical range of patient sizes. Using the available thermometry and treatment planning, the BSD-2000 hyperthermia system was shown to be an effective method of focusing heat regionally around the bladder with good patient tolerance.


Asunto(s)
Hipertermia Inducida , Neoplasias de la Vejiga Urinaria/terapia , Humanos , Invasividad Neoplásica , Satisfacción del Paciente , Tomografía Computarizada por Rayos X , Neoplasias de la Vejiga Urinaria/diagnóstico por imagen
9.
Int J Hyperthermia ; 30(1): 1-5, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24350642

RESUMEN

Like other technically sophisticated medical endeavours, a hyperthermia clinic relies on skilled staffing. Physicians, physicists and technologists perform multiple tasks to ensure properly functioning equipment, appropriate patient selection, and to plan and administer this treatment. This paper reviews the competencies and tasks that are used in a hyperthermia clinic.


Asunto(s)
Instituciones de Atención Ambulatoria , Hipertermia Inducida , Humanos , Hipertermia Inducida/instrumentación , Cuerpo Médico , Monitoreo Fisiológico , Médicos , Termometría/instrumentación , Recursos Humanos
10.
Int J Hyperthermia ; 30(5): 285-94, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25144817

RESUMEN

PURPOSE: Unresectable chest wall recurrences of breast cancer (CWR) in heavily pretreated patients are especially difficult to treat. We hypothesised that thermally enhanced drug delivery using low temperature liposomal doxorubicin (LTLD), given with mild local hyperthermia (MLHT), will be safe and effective in this population. PATIENTS AND METHODS: This paper combines the results of two similarly designed phase I trials. Eligible CWR patients had progressed on the chest wall after prior hormone therapy, chemotherapy, and radiotherapy. Patients were to get six cycles of LTLD every 21-35 days, followed immediately by chest wall MLHT for 1 hour at 40-42 °C. In the first trial 18 subjects received LTLD at 20, 30, or 40 mg/m2; in the second trial, 11 subjects received LTLD at 40 or 50 mg/m2. RESULTS: The median age of all 29 patients enrolled was 57 years. Thirteen patients (45%) had distant metastases on enrolment. Patients had received a median dose of 256 mg/m2 of prior anthracyclines and a median dose of 61 Gy of prior radiation. The median number of study treatments that subjects completed was four. The maximum tolerated dose was 50 mg/m2, with seven subjects (24%) developing reversible grade 3-4 neutropenia and four (14%) reversible grade 3-4 leucopenia. The rate of overall local response was 48% (14/29, 95% CI: 30-66%), with. five patients (17%) achieving complete local responses and nine patients (31%) having partial local responses. CONCLUSION: LTLD at 50 mg/m2 and MLHT is safe. This combined therapy produces objective responses in heavily pretreated CWR patients. Future work should test thermally enhanced LTLD delivery in a less advanced patient population.


Asunto(s)
Adenocarcinoma/terapia , Antibióticos Antineoplásicos , Neoplasias de la Mama/terapia , Doxorrubicina/análogos & derivados , Hipertermia Inducida , Recurrencia Local de Neoplasia/terapia , Adenocarcinoma/sangre , Adulto , Anciano , Antibióticos Antineoplásicos/efectos adversos , Antibióticos Antineoplásicos/sangre , Antibióticos Antineoplásicos/farmacocinética , Antibióticos Antineoplásicos/uso terapéutico , Neoplasias de la Mama/sangre , Terapia Combinada , Doxorrubicina/efectos adversos , Doxorrubicina/sangre , Doxorrubicina/farmacocinética , Doxorrubicina/uso terapéutico , Femenino , Humanos , Dosis Máxima Tolerada , Persona de Mediana Edad , Recurrencia Local de Neoplasia/sangre , Polietilenglicoles/efectos adversos , Polietilenglicoles/farmacocinética , Polietilenglicoles/uso terapéutico , Temperatura , Resultado del Tratamiento
11.
Int J Radiat Oncol Biol Phys ; 118(2): 404-414, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-37652301

RESUMEN

PURPOSE: Radiation therapy is part of the standard treatment regimen for non-small cell lung cancer (NSCLC). Although radiation therapy is an effective tool to manage NSCLC, it can be associated with significant dose-limiting toxicities. These toxicities can lead to treatment interruption or early termination and worsening clinical outcomes in addition to reductions in patient quality of life. Based on preclinical efficacy for radioprotection of normal tissues, we evaluated the clinical utility of BIO 300 Oral Suspension (BIO 300; synthetic genistein nanosuspension) in patients with NSCLC. METHODS AND MATERIALS: In this multicenter, open-label, single-arm, ascending dose phase 1b/2a study, patients were enrolled with newly diagnosed stage II-IV NSCLC planned for 60 to 70/1.8-2.0 Gy radiation therapy and concurrent weekly paclitaxel/carboplatin. Oral BIO 300 (cohort 1, 500 mg/d; cohort 2, 1000 mg/d; cohort 3, 1500 mg/d) was self-administered once daily starting 2 to 7 days before initiating concurrent chemoradiotherapy and continued until the end of radiation therapy. The primary endpoint was acute dose-limiting toxicities attributable to BIO 300. Secondary outcomes included pharmacokinetics, pharmacodynamics, overall toxicity profile, quality of life, local response rate, and survival. RESULTS: Twenty-one participants were enrolled. No dose-limiting toxicities were reported. BIO 300 dosing did not alter chemotherapy pharmacokinetics. Adverse events were not dose-dependent, and those attributable to BIO 300 (n = 11) were all mild to moderate in severity (grade 1, n = 9; grade 2, n = 2) and predominantly gastrointestinal (n = 7). A dose-dependent decrease in serum transforming growth factor ß1 levels was observed across cohorts. Based on safety analysis, the maximum tolerated dose of BIO 300 was not met. Patient-reported quality of life and weight were largely stable throughout the study period. No patient had progression as their best overall response, and a 65% tumor response rate was achieved (20% complete response rate). CONCLUSIONS: The low toxicity rates, along with the pharmacodynamic results and tumor response rates, support further investigation of BIO 300 as an effective radioprotector.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Carcinoma de Pulmón de Células no Pequeñas/patología , Neoplasias Pulmonares/patología , Calidad de Vida , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Quimioradioterapia/efectos adversos , Quimioradioterapia/métodos , Carboplatino , Paclitaxel
12.
Biochim Biophys Acta ; 1822(5): 794-814, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22198225

RESUMEN

Increased understanding of the role of mitochondria under physiological and pathological conditions parallels increased exploration of synthetic and natural compounds able to mimic MnSOD - endogenous mitochondrial antioxidant defense essential for the existence of virtually all aerobic organisms from bacteria to humans. This review describes most successful mitochondrially-targeted redox-active compounds, Mn porphyrins and MitoQ(10) in detail, and briefly addresses several other compounds that are either catalysts of O(2)(-) dismutation, or its non-catalytic scavengers, and that reportedly attenuate mitochondrial dysfunction. While not a true catalyst (SOD mimic) of O(2)(-) dismutation, MitoQ(10) oxidizes O(2)(-) to O(2) with a high rate constant. In vivo it is readily reduced to quinol, MitoQH(2), which in turn reduces ONOO(-) to NO(2), producing semiquinone radical that subsequently dismutes to MitoQ(10) and MitoQH(2), completing the "catalytic" cycle. In MitoQ(10), the redox-active unit was coupled via 10-carbon atom alkyl chain to monocationic triphenylphosphonium ion in order to reach the mitochondria. Mn porphyrin-based SOD mimics, however, were designed so that their multiple cationic charge and alkyl chains determine both their remarkable SOD potency and carry them into the mitochondria. Several animal efficacy studies such as skin carcinogenesis and UVB-mediated mtDNA damage, and subcellular distribution studies of Saccharomyces cerevisiae and mouse heart provided unambiguous evidence that Mn porphyrins mimic the site and action of MnSOD, which in turn contributes to their efficacy in numerous in vitro and in vivo models of oxidative stress. Within a class of Mn porphyrins, lipophilic analogs are particularly effective for treating central nervous system injuries where mitochondria play key role. This article is part of a Special Issue entitled: Antioxidants and Antioxidant Treatment in Disease.


Asunto(s)
Imitación Molecular , Superóxido Dismutasa/metabolismo , Humanos , Mitocondrias/metabolismo , Porfirinas/metabolismo , Superóxido Dismutasa/química
13.
Med Princ Pract ; 22(2): 103-30, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23075911

RESUMEN

Based on aqueous redox chemistry and simple in vivo models of oxidative stress, Escherichia coli and Saccharomyces cerevisiae, the cationic Mn(III) N-substituted pyridylporphyrins (MnPs) have been identified as the most potent cellular redox modulators within the porphyrin class of drugs; their efficacy in animal models of diseases that have oxidative stress in common is based on their high ability to catalytically remove superoxide, peroxynitrite, carbonate anion radical, hypochlorite, nitric oxide, lipid peroxyl and alkoxyl radicals, thus suppressing the primary oxidative event. While doing so MnPs could couple with cellular reductants and redox-active proteins. Reactive species are widely accepted as regulators of cellular transcriptional activity: minute, nanomolar levels are essential for normal cell function, while submicromolar or micromolar levels impose oxidative stress, which is evidenced in increased inflammatory and immune responses. By removing reactive species, MnPs affect redox-based cellular transcriptional activity and consequently secondary oxidative stress, and in turn inflammatory processes. The equal ability to reduce and oxidize superoxide during the dismutation process and recently accumulated results suggest that pro-oxidative actions of MnPs may also contribute to their therapeutic effects. All our data identify the superoxide dismutase-like activity, estimated by log k(cat)O2-*), as a good measure for the therapeutic efficacy of MnPs. Their accumulation in mitochondria and their ability to cross the blood-brain barrier contribute to their remarkable efficacy. We summarize herein the therapeutic effects of MnPs in cancer, central nervous system injuries, diabetes, their radioprotective action and potential for imaging. Few of the most potent modulators of cellular redox-based pathways, MnTE2-PyP5+, MnTDE-2-ImP5+, MnTnHex-2-PyP5+ and MnTnBuOE-2-PyP5+, are under preclinical and clinical development.


Asunto(s)
Depuradores de Radicales Libres/farmacología , Estrés Oxidativo/efectos de los fármacos , Porfirinas/farmacología , Animales , Área Bajo la Curva , Disponibilidad Biológica , Enfermedades del Sistema Nervioso Central/tratamiento farmacológico , Medios de Contraste/química , Diabetes Mellitus/tratamiento farmacológico , Modelos Animales de Enfermedad , Depuradores de Radicales Libres/química , Manganeso/química , Manganeso/farmacología , Neoplasias/tratamiento farmacológico , Oxidación-Reducción , Porfirinas/química , Superóxido Dismutasa/química , Superóxido Dismutasa/farmacología
14.
J Urol ; 187(1): 103-8, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22088334

RESUMEN

PURPOSE: The multidisciplinary approach is becoming increasingly encouraged but little is known about the multidisciplinary experience compared to routine care. For patients with prostate cancer the goal is to provide evaluations by urologists, medical and radiation oncologists at a single visit. Although additional resources are required, this strategy may enhance the overall health care experience. We compared utilization determinants between a multidisciplinary and a urology prostate cancer clinic at Duke University Medical Center and identified factors associated with pursuing treatment at the university medical center for multidisciplinary clinic patients. MATERIALS AND METHODS: We retrospectively analyzed data on patients referred for primary prostate cancer treatment evaluation at Duke University Medical Center from 2005 to 2009. Comparisons between 701 multidisciplinary clinic and 1,318 urology prostate cancer clinic patients were examined with the rank sum and chi-square tests. Predictive factors for pursuing treatment at the university medical center were assessed using multivariate adjusted logistic regression. RESULTS: Compared to patients at the urology prostate cancer clinic those at the multidisciplinary clinic were more likely to be younger and white, have a higher income and travel a longer distance for evaluation. Of multidisciplinary clinic patients 58% pursued primary treatment at the university medical center. They were more likely to be younger, black and physician referred, have a lower income and reside closer to the medical center. Factors predictive of pursuing treatment at the medical center included high risk disease and physician referral. Factors predictive of not receiving care at the university medical center were income greater than $40,000 and a distance traveled of greater than 100 miles. CONCLUSIONS: A different patient demographic is using the multidisciplinary approach. However, when treatment is pursued at the institution providing multidisciplinary services, the patient demographic resembles that of the treating institution.


Asunto(s)
Grupo de Atención al Paciente/estadística & datos numéricos , Neoplasias de la Próstata/terapia , Anciano , Instituciones de Salud , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Tiempo
15.
Amino Acids ; 42(1): 95-113, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20473774

RESUMEN

The most efficacious Mn(III) porphyrinic (MnPs) scavengers of reactive species have positive charges close to the Mn site, whereby they afford thermodynamic and electrostatic facilitation for the reaction with negatively charged species such as O (2) (•-) and ONOO(-). Those are Mn(III) meso tetrakis(N-alkylpyridinium-2-yl)porphyrins, more specifically MnTE-2-PyP(5+) (AEOL10113) and MnTnHex-2-PyP(5+) (where alkyls are ethyl and n-hexyl, respectively), and their imidazolium analog, MnTDE-2-ImP(5+) (AEOL10150, Mn(III) meso tetrakis(N,N'-diethylimidazolium-2-yl) porphyrin). The efficacy of MnPs in vivo is determined not only by the compound antioxidant potency, but also by its bioavailability. The former is greatly affected by the lipophilicity, size, structure, and overall shape of the compound. These porphyrins have the ability to both eliminate reactive oxygen species and impact the progression of oxidative stress-dependent signaling events. This will effectively lead to the regulation of redox-dependent transcription factors and the suppression of secondary inflammatory- and oxidative stress-mediated immune responses. We have reported on the inhibition of major transcription factors HIF-1α, AP-1, SP-1, and NF-κB by Mn porphyrins. While the prevailing mechanistic view of the suppression of transcription factors activation is via antioxidative action (presumably in cytosol), the pro-oxidative action of MnPs in suppressing NF-κB activation in nucleus has been substantiated. The magnitude of the effect is dependent upon the electrostatic (porphyrin charges) and thermodynamic factors (porphyrin redox ability). The pro-oxidative action of MnPs has been suggested to contribute at least in part to the in vitro anticancer action of MnTE-2-PyP(5+) in the presence of ascorbate, and in vivo when combined with chemotherapy of lymphoma. Given the remarkable therapeutic potential of metalloporphyrins, future studies are warranted to further our understanding of in vivo action/s of Mn porphyrins, particularly with respect to their subcellular distribution.


Asunto(s)
Manganeso/metabolismo , Metaloporfirinas/metabolismo , Metaloporfirinas/farmacología , Estrés Oxidativo/efectos de los fármacos , Activación Transcripcional/efectos de los fármacos , Animales , Humanos , Manganeso/química , Metaloporfirinas/química , Oxidación-Reducción/efectos de los fármacos
16.
BJU Int ; 110(11 Pt C): E931-8, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22520165

RESUMEN

UNLABELLED: Study Type--Therapy (case series) Level of Evidence 4. What's known on the subject? and What does the study add? The role of the vacuum erection device (VED) has increased with its use in combined therapy with a phosphodiesterase type 5 inhibitor (PDE5i) for penile rehabilitation after radical prostatectomy (RP) and radiotherapy. The advantages of the VED are non-invasive, cost-effective, and a possibility of preventing shrinkage of penis length. Albeit current widespread use of penile rehabilitation programmes for post-RP erectile dysfunction, independent predictors for the rehabilitation participants, as well as for its treatment success have not been fully investigated. In the present study, we have added several new predictors for rehabilitation participation, e.g. African-Americans and higher preoperative sexual function. Conversely, higher preoperative PSA concentrations and the presence of positive surgical margins were predictors for avoidance of rehabilitation. Notably, there was a primary surgeon difference, which had a trend for predicting outcome of the rehabilitation among the participants, implying their surgical technique and follow-up might influence success of the rehabilitation. OBJECTIVES: • To investigate baseline demographic and clinicopathological characteristics of men who participate in our penile rehabilitation programme after radical prostatectomy (RP). • To determine predictors for participation in rehabilitation, as well as successful rehabilitation outcome using multivariable logistic regression analyses. PATIENTS AND METHODS: • We analysed data on 2345 consecutive patients who underwent RP between 2001 and 2009 in our institution. • The decision to participate in penile rehabilitation using phosphodiesterase type 5 inhibitor (PDE5i) with a vacuum erection device (VED) was based on the patient's choice after post-RP discussions. • Rehabilitation success was defined using the following criteria: (i) patients who continued the penile rehabilitation programme and did not switch treatment from PDE5i to other erectile aids, (ii) success was noted in men who had an Expanded Prostate Cancer Index Composite (EPIC) sexual function (SF) score of >75% of the patient's baseline EPIC score, and (iii) patients who answered that they achieved adequate erections with a PDE5i. • Logistic regression analysis was used to identify factors associated with treatment participation and its success. RESULTS: • Of 676 patients, 354 (53.2%) men participated in a penile rehabilitation programme. Among 329 rehabilitation participants with available data, 96 (29.2%) had treatment success. • In multivariable regression analysis, African-Americans (odds ratio [OR] 3.47, P < 0.001), and higher preoperative SF (OR 1.02, P < 0.001) were associated with participation in rehabilitation. • Higher preoperative PSA concentration (OR 0.50, P = 0.004) and presence of positive surgical margins (OR 0.68, P = 0.042) were found to be independent predictors for non-participation in the rehabilitation. • For rehabilitation outcomes, being older at surgery (OR 0.93, P = 0.001) and adjuvant therapy (OR 0.34, P = 0.047) had a negative association with successful outcome. • There was a trend in the relationship between primary surgeon and rehabilitation success (OR 1.05, P = 0.053) CONCLUSIONS: • Those patients who have risk factors, e.g. adverse prostate cancer features, need to be carefully counselled and encouraged to participate in the penile rehabilitation programme. • Clinicians could lead patients toward successful outcomes if appropriate surgical techniques and rehabilitation are provided.


Asunto(s)
Impotencia Vasculogénica/rehabilitación , Cooperación del Paciente , Erección Peniana/efectos de los fármacos , Prótesis de Pene , Pene/efectos de los fármacos , Inhibidores de Fosfodiesterasa 5/uso terapéutico , Prostatectomía/efectos adversos , Estudios de Seguimiento , Humanos , Impotencia Vasculogénica/etiología , Masculino , Persona de Mediana Edad , Pene/fisiología , Neoplasias de la Próstata/cirugía , Estudios Retrospectivos , Factores de Riesgo , Resultado del Tratamiento , Vacio
17.
J Sex Med ; 9(6): 1535-49, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22489731

RESUMEN

INTRODUCTION: Chronic oxidative stress is one of the major factors playing an important role in radiation-induced normal tissue injury. However, the role of oxidative stress in radiation-induced erectile dysfunction (ED) has not been fully investigated. Aims. To investigate role of oxidative stress after prostate-confined irradiation in a rat model of radiation-induced ED. METHODS: Fifty-four young adult male rats (10-12 weeks of age) were divided into age-matched sham radiotherapy (RT) and RT groups. Irradiated animals received prostate-confined radiation in a single 20 Gy fraction. MAIN OUTCOME MEASURES: Intracavernous pressure (ICP) measurements with cavernous nerve electrical stimulation were conducted at 2, 4, and 9 weeks following RT. The protein expression of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase subunits (Nox4 and gp91(phox)), markers of oxidative DNA damage (8-hydroxy-2'-deoxyguanosine [8-OHdG]), lipid peroxidation (4-hydroxynonenal [4HNE]), and inflammatory response including inducible nitric oxide synthase, macrophage activation (ED-1), and nitrotyrosine, and endogenous antioxidant defense by nuclear factor erythroid 2-related factor (Nrf2) were evaluated in irradiated prostate tissue and corpora cavernosa (CC). In addition, we investigated the relationships between results of ICP/mean arterial pressure (MAP) ratios and expression level of oxidative stress markers. RESULTS: In the RT group, hemodynamic functional studies demonstrated a significant time-dependent decrease in ICP. Increased expression of Nox4, gp91(phox), 8-OHdG, and 4HNE were observed in the prostate and CC after RT. Similarly, expressions of inflammatory markers were significantly increased. There was a trend for increased Nrf2 after 4 weeks. ICP/MAP ratio negatively correlated with higher expression level of oxidative markers. CONCLUSION: NADPH oxidase activation and chronic oxidative stress were observed in irradiated prostate tissue and CC, which correlated with lower ICP/MAP ratio. Persistent inflammatory responses were also found in both tissues after RT. These findings suggest that oxidative stress plays a crucial role in the development of radiation-induced ED.


Asunto(s)
Disfunción Eréctil/fisiopatología , Estrés Oxidativo , Traumatismos Experimentales por Radiación/fisiopatología , Radioterapia/efectos adversos , Animales , Biomarcadores/metabolismo , Modelos Animales de Enfermedad , Disfunción Eréctil/etiología , Inflamación/metabolismo , Masculino , Análisis por Apareamiento , NADPH Oxidasas/metabolismo , Erección Peniana , Pene/metabolismo , Pene/fisiopatología , Próstata/metabolismo , Próstata/fisiopatología , Neoplasias de la Próstata/radioterapia , Ratas , Ratas Sprague-Dawley
18.
Med Phys ; 39(3): 1170-81, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22380348

RESUMEN

PURPOSE: A recently completed Phase I clinical trial combined concurrent Mitomycin-C chemotherapy with deep regional heating using BSD-2000 Sigma-Ellipse applicator (BSD Corporation, Salt Lake City, UT, U.S.A.) for the treatment of nonmuscle invasive bladder cancer. This work presents a new treatment planning approach, and demonstrates potential impact of this approach on improvement of treatment quality. METHODS: This study retrospectively analyzes a subset of five patients on the trial. For each treatment, expert operators selected "clinical-optimal" settings based on simple model calculation on the BSD-2000 control console. Computed tomography (CT) scans acquired prior to treatment were segmented to create finite element patient models for retrospective simulations with Sigma-HyperPlan (Dr. Sennewald Medizintechnik GmbH, Munchen, Germany). Since Sigma-HyperPlan does not account for the convective nature of heat transfer within a fluid filled bladder, an effective thermal conductivity for bladder was introduced. This effective thermal conductivity value was determined by comparing simulation results with clinical measurements of bladder and rectum temperatures. Regions of predicted high temperature in normal tissues were compared with patient complaints during treatment. Treatment results using "computed-optimal" settings from the planning system were compared with clinical results using clinical-optimal settings to evaluate potential of treatment improvement by reducing hot spot volume. RESULTS: For all five patients, retrospective treatment planning indicated improved matches between simulated and measured bladder temperatures with increasing effective thermal conductivity. The differences were mostly within 1.3 °C when using an effective thermal conductivity value above 10 W/K/m. Changes in effective bladder thermal conductivity affected surrounding normal tissues within a distance of ∼1.5 cm from the bladder wall. Rectal temperature differences between simulation and measurement were large due to sensitivity to the sampling locations in rectum. The predicted bladder T90 correlated well with single-point bladder temperature measurement. Hot spot locations predicted by the simulation agreed qualitatively with patient complaints during treatment. Furthermore, comparison between the temperature distributions with clinical and computed-optimal settings demonstrated that the computed-optimal settings resulted in substantially reduced hot spot volumes. CONCLUSIONS: Determination of an effective thermal conductivity value for fluid filled bladder was essential for matching simulation and treatment temperatures. Prospectively planning patients using the effective thermal conductivity determined in this work can potentially improve treatment efficacy (compared to manual operator adjustments) by potentially lower discomfort from reduced hot spots in normal tissue.


Asunto(s)
Hipertermia Inducida/métodos , Neoplasias de la Vejiga Urinaria/terapia , Campos Electromagnéticos , Humanos , Estudios Retrospectivos , Temperatura , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico
19.
Radiat Res ; 197(3): 209-217, 2022 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-34860238

RESUMEN

Cell line misidentification and contamination are major contributors to the reproducibility crisis in academic research. Authentication of cell lines provides assurances of the data generated; however, commercially available cells are often not subjected to rigorous identification testing. In this study, commercially available cell lines underwent testing to confirm cell identity and purity. The methods reported here outline the best practices for cell line authentication. Briefly, a commercially available primary rabbit aortic endothelial cell line was purchased for the intent of producing target proteins necessary for generating species-specific recombinant antibodies. These rabbit-specific antibodies would then be utilized for the development of in-house enzyme-linked immunosorbent assays (ELISA) to evaluate blood-based biomarkers of vascular injury after total-body irradiation. To authenticate the cell line, cell identity and purity were determined by single tandem repeat (STR) testing, flow cytometry, polymerase chain reaction (PCR), and cytochrome c oxidase subunit 1 (CO1) DNA Barcoding in-house and/or through commercial vendors. Fresh cells obtained from a New Zealand White rabbit (Charles River, Wilmington, DE) were used as a positive control. The results of STR and flow cytometry analyses indicated the cells were not contaminated with human or mouse cells, and that the cells were not of endothelial origin. PCR demonstrated that cells were also not of rabbit origin, which was further confirmed by a third-party vendor. An unopened vial of cells was submitted to another vendor for CO1 DNA Barcoding analysis, which identified the cells as being purely of bovine origin. Results revealed that despite purchase through a commercial vendor, the cell line marketed as primary rabbit aortic endothelial cells were of bovine origin. Purity analysis found cells were misidentified rather than contaminated. Further investigation to determine the cell type was not performed. The most cost-effective and efficient methodology for confirming cell line identity was found to be CO1 DNA Barcoding performed by a commercial vendor.


Asunto(s)
ADN , Células Endoteliales , Animales , Bovinos , Línea Celular , Ratones , Reacción en Cadena de la Polimerasa , Conejos , Reproducibilidad de los Resultados
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