RESUMEN
Cancer is one of the main causes of death worldwide. To date, and despite the advances in conventional treatment options, therapy in cancer is still far from optimal due to the non-specific systemic biodistribution of antitumor agents. The inadequate drug concentrations at the tumor site led to an increased incidence of multiple drug resistance and the appearance of many severe undesirable side effects. Nanotechnology, through the development of nanoscale-based pharmaceuticals, has emerged to provide new and innovative drugs to overcome these limitations. In this review, we provide an overview of the approved nanomedicine for cancer treatment and the rationale behind their designs and applications. We also highlight the new approaches that are currently under investigation and the perspectives and challenges for nanopharmaceuticals, focusing on the tumor microenvironment and tumor disseminate cells as the most attractive and effective strategies for cancer treatments.
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Antineoplásicos , Neoplasias , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Humanos , Nanomedicina , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Preparaciones Farmacéuticas , Distribución Tisular , Microambiente TumoralRESUMEN
Prostacyclin (PGI2 ) plays a role in cancer progression but the mechanism is currently poorly understood. Additionally, no data are available about the prognostic value of the PGI2 pathway in head and neck squamous cell carcinoma (HNSCC) therapy. We evaluated the expression of the PGI2 pathway in HNSCC patients. PGI2 production and PGI synthase (PGIS) expression, in terms of mRNA (RT-PCR) and protein (immunoblotting), were lower in tumour samples than in non-tumoural mucosa, whereas, as expected, COX-2 expression was increased in HNSCC tumour samples. Using local control of the tumour after radiotherapy or chemoradiotherapy as a dependent variable, patients were classified into two categories of PGIS transcript levels. The high-PGIS group had a significantly lower frequency of local and distant failure than the low-PGIS group, and the 5-year cancer-specific survival was higher [90.2% (95% CI 81.0-99.4%) versus 60.5% (95% CI 44.4-76.6%)]. None of the four HNSCC cell lines analysed expressed PGIS and therefore they did not produce PGI2 . However, HNSCC-conditioned media enhanced PGI2 production in endothelial cells (ECs). The stable analogue of PGI2 , carbaprostacyclin (cPGI2 ), exerted little effect on HNSCC cell line migration, and no effect on cell cycle distribution or proliferation rate after radiation injury was observed. Nevertheless, cPGI2 promoted EP-4-dependent in vitro angiogenesis. Von Willebrand factor expression (EC marker) and capillary density were significantly higher in the group of patients with high expression of PGIS. Our results indicate that PGIS expression was associated with radiotherapy efficiency. Although we do not provide direct evidence of a relationship between tumour vascularization and radiotherapy efficiency, our results suggest that the effect of PGI2 is related to its ability to promote vascularization. These results also support the concept that co-adjuvant therapy with PGIS enhancers, such as retinoids, could have therapeutic value for HNSCC treatment.
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Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/radioterapia , Sistema Enzimático del Citocromo P-450/metabolismo , Endotelio Vascular/metabolismo , Neoplasias de Cabeza y Cuello/metabolismo , Neoplasias de Cabeza y Cuello/radioterapia , Oxidorreductasas Intramoleculares/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/mortalidad , Células Cultivadas , Ciclooxigenasa 2/metabolismo , Femenino , Neoplasias de Cabeza y Cuello/mortalidad , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Carcinoma de Células Escamosas de Cabeza y CuelloRESUMEN
Radiotherapy (XRT) delivered with the antibody cetuximab is a standard treatment option for squamous cell carcinomas of head and neck (SCCNH). Cetuximab acts by blocking epidermal growth factor receptor (EGFR) signaling to inhibit cancer progression. However, a significant percentage of patients will not respond to XRT and cetuximab. Statins reduce the synthesis of cholesterol and isoprenoid derivates that may be required for efficient EGFR signaling. We assessed whether the statin simvastatin could improve this combined therapy. In vitro, simvastatin enhanced the effects of XRT alone and in combination with cetuximab in wound healing, cell proliferation, and clonogenic assays in FaDu cells. These results were reflected in xenoimplanted tumors growing into subcutaneous tissue of athymic mice where concomitant treatment with simvastatin decreased tumor growth. Consistently, lower levels of phosphorylated extracellular signal-regulated kinases 1 and 2, phosphatidylinositol 3-kinase/AKT-protein kinase B, and signal transducer and activator of transcription 3 oncoproteins and higher levels of caspase-3 and apoptosis in cell cultures and xenografts were observed. The EGFR-overexpressing A431 cell line was used to reproduce these antitumor effects of simvastatin. Our findings suggest that simvastatin may improve the efficiency of concomitant XRT and cetuximab. Further investigation in the treatment of SCCNH is warranted.
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INTRODUCTION: Endocrine therapies targeting cell proliferation and survival mediated by estrogen receptor α (ERα) are among the most effective systemic treatments for ERα-positive breast cancer. However, most tumors initially responsive to these therapies acquire resistance through mechanisms that involve ERα transcriptional regulatory plasticity. Herein we identify VAV3 as a critical component in this process. METHODS: A cell-based chemical compound screen was carried out to identify therapeutic strategies against resistance to endocrine therapy. Binding to ERα was evaluated by molecular docking analyses, an agonist fluoligand assay and short hairpin (sh)RNA-mediated protein depletion. Microarray analyses were performed to identify altered gene expression. Western blot analysis of signaling and proliferation markers, and shRNA-mediated protein depletion in viability and clonogenic assays, were performed to delineate the role of VAV3. Genetic variation in VAV3 was assessed for association with the response to tamoxifen. Immunohistochemical analyses of VAV3 were carried out to determine its association with therapeutic response and different tumor markers. An analysis of gene expression association with drug sensitivity was carried out to identify a potential therapeutic approach based on differential VAV3 expression. RESULTS: The compound YC-1 was found to comparatively reduce the viability of cell models of acquired resistance. This effect was probably not due to activation of its canonical target (soluble guanylyl cyclase), but instead was likely a result of binding to ERα. VAV3 was selectively reduced upon exposure to YC-1 or ERα depletion, and, accordingly, VAV3 depletion comparatively reduced the viability of cell models of acquired resistance. In the clinical scenario, germline variation in VAV3 was associated with the response to tamoxifen in Japanese breast cancer patients (rs10494071 combined P value = 8.4 × 10-4). The allele association combined with gene expression analyses indicated that low VAV3 expression predicts better clinical outcome. Conversely, high nuclear VAV3 expression in tumor cells was associated with poorer endocrine therapy response. Based on VAV3 expression levels and the response to erlotinib in cancer cell lines, targeting EGFR signaling may be a promising therapeutic strategy. CONCLUSIONS: This study proposes VAV3 as a biomarker and a rationale for its use as a signaling target to prevent and/or overcome resistance to endocrine therapy in breast cancer.
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Neoplasias de la Mama/tratamiento farmacológico , Resistencia a Antineoplásicos/genética , Receptor alfa de Estrógeno/metabolismo , Indazoles/farmacología , Proteínas Proto-Oncogénicas c-vav/genética , Androstadienos/uso terapéutico , Antineoplásicos Hormonales/farmacología , Inhibidores de la Aromatasa/uso terapéutico , Biomarcadores de Tumor/genética , Mama/patología , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Activadores de Enzimas/farmacología , Receptores ErbB/antagonistas & inhibidores , Clorhidrato de Erlotinib , Receptor alfa de Estrógeno/antagonistas & inhibidores , Receptor alfa de Estrógeno/genética , Femenino , Regulación Neoplásica de la Expresión Génica , Estudios de Asociación Genética , Variación Genética , Humanos , Letrozol , Células MCF-7 , Nitrilos/uso terapéutico , Inhibidores de Proteínas Quinasas/farmacología , Quinazolinas/farmacología , Interferencia de ARN , ARN Interferente Pequeño , Tamoxifeno/farmacología , Tamoxifeno/uso terapéutico , Toremifeno/farmacología , Toremifeno/uso terapéutico , Triazoles/uso terapéuticoRESUMEN
INTRODUCTION: Radiation resistance is a major cause of death in cancer patients. Cancer cells react during radiotherapy by re-programming specific cell functions that may confer resistance to radiation. The understanding of this complex process is hindered due to the lack of appropriate study models. We describe an experimental development of a radioresistant isogenic cancer cell line, and its molecular characterization. MATERIALS AND METHODS: A431-cultured cells were irradiated for 7 month until 85 Gy. Then, a selected single cell was left to grow as stable A431-R cell line. Clonogenic assay was used to determine cell survival, the α and ß parameters of the LQ model, and the mean inactivation dose. The DNA repair ability of cells was evaluated by pulsed-field electrophoresis method. Differential effect of fractionated radiation was ultimately tested in xenografts. Furthermore, we used a wound healing assay, Western blot for EGFR, AKT and ERK1/2 and ELISA test for vascular endothelial growth factor (VEGF) secretion. Finally we explored CD44 marker and cell cycle distribution. RESULTS: The established A431-R cell line showed radiation resistance in clonogenic assays, repair of radiation-induced DNA fragmentation and xenografted tumours. The radiation resistance was associated with in vitro higher cell growth and migration, increased levels of former oncoproteins, and secretion of VEGF. CONCLUSIONS: In this model, the emergence of radiation resistance was associated with the acquisition of biological traits that support more aggressive behaviour of cancer cells. We have generated a model that will be useful for mechanistic studies and development of rational treatments against radiation resistance in cancer.
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Carcinoma de Células Escamosas/patología , Tolerancia a Radiación , Animales , Apoptosis , Western Blotting , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/radioterapia , Ciclo Celular , Movimiento Celular , Proliferación Celular , Relación Dosis-Respuesta en la Radiación , Femenino , Citometría de Flujo , Rayos gamma , Humanos , Receptores de Hialuranos/metabolismo , Ratones , Ratones Desnudos , Fenotipo , Células Tumorales Cultivadas , Factor A de Crecimiento Endotelial Vascular/metabolismo , Cicatrización de Heridas , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
The need for using immunodeficient mice for xenoimplantation of tumours is increasing in translational research in radiation oncology. However, adverse effects of radiation and infectious diseases may ruin the experimental work, in particular when appropriate facilities are not available. In this report, we describe a procedure to deliver fractionated radiotherapy to xenoimplanted tumours in immunodeficient mice using a medical linear accelerator, a method that was devised as an alternative to the lack of facilities devoted to radiation research. The mice were irradiated under anaesthesia and aseptic conditions. Thirty Gray in 10 days using a 6 MV photon beam were delivered only to the right thigh of the mice where tumours were implanted. The mice were evaluated twice a week up to planned euthanasia. The follow-up of mice was completed without premature interruption due to toxicities or infectious diseases, an observation which demonstrates the feasibility of the method.
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Fraccionamiento de la Dosis de Radiación , Aceleradores de Partículas/instrumentación , Oncología por Radiación/métodos , Protección Radiológica/métodos , Radioterapia/métodos , Animales , Femenino , Humanos , Ratones , Ratones Desnudos , Trasplante de Neoplasias , Neoplasias/radioterapia , Radioterapia/instrumentación , Factores de Tiempo , Trasplante HeterólogoRESUMEN
BACKGROUND: Radiation-induced DNA double-strand break (DSB) repair can be tested by using pulsed-field gel electrophoresis (PFGE) in agarose-encapsulated cells. However, previous studies have reported that this assay is impaired by the spontaneous DNA breakage in this medium. We investigated the mechanisms of this fragmentation with the principal aim of eliminating it in order to improve the estimation of radiation-induced DNA repair. METHODS: Samples from cancer cell cultures or xenografted tumours were encapsulated in agarose plugs. The cell plugs were then irradiated, incubated to allow them to repair, and evaluated by PFGE, caspase-3, and histone H2AX activation (γH2AX). In addition, apoptosis inhibition was evaluated through chemical caspase inhibitors. RESULTS: We confirmed that spontaneous DNA fragmentation was associated with the process of encapsulation, regardless of whether cells were irradiated or not. This DNA fragmentation was also correlated to apoptosis activation in a fraction of the cells encapsulated in agarose, while non-apoptotic cell fraction could rejoin DNA fragments as was measured by γH2AX decrease and PFGE data. We were able to eliminate interference of apoptosis by applying specific caspase inhibitors, and improve the estimation of DNA repair, and apoptosis itself. CONCLUSIONS: The estimation of radiation-induced DNA repair by PFGE may be improved by the use of apoptosis inhibitors. The ability to simultaneously determine DNA repair and apoptosis, which are involved in cell fate, provides new insights for using the PFGE methodology as functional assay.
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Apoptosis/efectos de la radiación , Inhibidores de Caspasas , Reparación del ADN/efectos de la radiación , Electroforesis en Gel de Campo Pulsado/métodos , Inhibidores Enzimáticos/farmacología , Animales , Apoptosis/fisiología , Roturas del ADN de Doble Cadena/efectos de los fármacos , Fragmentación del ADN/efectos de los fármacos , Relación Dosis-Respuesta en la Radiación , Electroforesis en Gel de Campo Pulsado/normas , Humanos , Masculino , Ratones , Ratones Desnudos , Neoplasias/genética , Neoplasias/patología , Neoplasias/radioterapia , Estadística como Asunto , Trasplante Heterólogo , Células Tumorales CultivadasRESUMEN
BACKGROUND: The benefits of radiotherapy and cetuximab have encouraged evaluation of cetuximab after radiotherapy. The aims of this study were to preclinically evaluate the efficacy of cetuximab maintenance after radiotherapy and eventually determine its mechanisms of action. METHODS: The A431 human carcinoma cell line was treated in culture with fractionated radiotherapy and cetuximab. The surviving cells were injected s.c. into nude mice to mimic microscopic residual disease. The animals were randomized to receive either cetuximab or saline solution. Tumor growth, cell proliferation (Ki-67), microvessel density (MVD), epidermal growth factor receptor (EGFR) and transforming growth factor (TGF-α) mRNA transcription, and vascular endothelial growth factor (VEGF) secretion were measured. RESULTS: Tumors from irradiated cells had a faster growth rate, higher Ki-67 index, and greater angiogenesis than tumors from untreated cells. This aggressive phenotype was associated with in vitro radiation-induced extracellular signal-related kinase (ERK)-1/2 and Akt activation, greater EGFR and TGF-α transcription, and augmented VEGF secretion, all of which were inhibited by cetuximab. In cetuximab-treated mice with tumors arising from irradiated cells, time to volume was longer by a factor of 3.52, whereas the Ki-67 index and MVD were 1.57 and 1.49 times lower, respectively, a larger enhancement than seen in tumors from untreated cells. These findings suggest that cells surviving radiation may express factors that promote cell survival and induce an aggressive phenotype that may potentially be blocked by cetuximab maintenance therapy. CONCLUSIONS: These results support the clinical evaluation of adjuvant therapy with cetuximab after radiotherapy in EGFR-dependent carcinomas.
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Inhibidores de la Angiogénesis/uso terapéutico , Anticuerpos Monoclonales/uso terapéutico , Antineoplásicos/uso terapéutico , Receptores ErbB/antagonistas & inhibidores , Neoplasias Experimentales/radioterapia , Animales , Anticuerpos Monoclonales Humanizados , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Cetuximab , Terapia Combinada , Citoprotección , Receptores ErbB/análisis , Humanos , Antígeno Ki-67/análisis , Masculino , Ratones , Neoplasias Experimentales/irrigación sanguínea , Neoplasias Experimentales/tratamiento farmacológico , Neoplasias Experimentales/patología , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
UNLABELLED: This phase II study evaluates the activity of temozolomide and cisplatin administered before radiation therapy in newly diagnosed glioblastoma multiforme patients, in terms of response, time to progression and survival. PATIENTS AND METHODS: Forty patients with measurable disease after surgery, a Karnofsky status > 60, and Barthel Index > 10 were included. They were treated with three cycles of temozolomide 200 mg/m2/day for 5 days and cisplatin 100 mg/m2 on day 1. Conventional focal radiation therapy to 60 Gy was administered after response evaluation. RESULTS: Three patients were not evaluable for central reviewed response but all 40 were evaluable for toxicity, time to progression and survival. Objective responses by Macdonald criteria on an intent to treat basis were 45% including complete response in three patients (7.5%), and partial response in 15 patients (37.5%). Responses were seen in biopsy-only patients (33.4%) as well as in partial surgery patients (52%). Median survival for all patients was 12.5 months. Biopsy-only patients had a median survival of 12.8 months. Grade 3 to 4 neutropenia was the most important toxicity, and occurred in 37.5% of patients. A delay in 18.2% and a dose reduction in 9.6% of cycles were necessary due to myelosuppression on day 28. Two patients had neutropenic fever resulting in one treatment-related death. Eighty-two percent of patients received radiotherapy. CONCLUSION: This regimen has significant activity, as it induces objective responses even in biopsy-only patients, appearing to improve their median survival. A better combination schedule is needed to improve the toxicity profile.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Encefálicas/mortalidad , Neoplasias Encefálicas/terapia , Dacarbazina/análogos & derivados , Glioblastoma/mortalidad , Glioblastoma/terapia , Adulto , Anciano , Cisplatino/administración & dosificación , Terapia Combinada , Dacarbazina/administración & dosificación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Radioterapia , Análisis de Supervivencia , Temozolomida , Resultado del TratamientoRESUMEN
BACKGROUND AND PURPOSE: Several clinical studies have suggested that the combination of radiation therapy and 5-fluorouracil (5-FU) may improve outcome of patients with pancreatic cancer. However, there are few experimental studies supporting this treatment. AIM OF THE STUDY: To examine the radiosensitivity of human pancreatic cancer cells and its modulation by 5-FU. MATERIAL AND METHODS: MiaPaCa-2, PANC-1 and NP-18 cells growing as monolayer culture were treated with radiation and 5-FU. In addition, 5-FU was studied administered either pre- or postradiation, both as pulse or continuous exposure. Cell survival was determined by the in vitro clonogenic assay. RESULTS: In MiaPaCa-2 cell line, both radiation and 5-FU alone reduced cell survival. The addition of 5-FU to radiation caused a significant net decrease of cell survival. Pulse exposure of 5-FU decreased survival after 2 Gy and mean inactivation dose by 1.64; continuous exposure decreased survival after 2 Gy and mean inactivation dose by about 2.4. Timing of 5-FU exposure did not modify survival. However, when adjusting for 5-FU killing effect and cell multiplicity, only continuous exposure significantly enhanced radiation cell killing. CONCLUSION: Both pulse and continuous exposure increase radiation cell killing, but only continuous exposure may radiosensitize MiaPaCa-2 cells.