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1.
Ann Transl Med ; 9(7): 571, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33987269

RESUMO

BACKGROUND: Glioblastoma (GBM) is the most common malignant brain tumor in adults. The prognosis of GBM patients is poor. Even with active standard treatment, the median overall survival is only 14.6 months. It is therefore critical to ascertain recurrence and search for factors that influence the prognosis of GBM. This study aimed to screen the variables related to the progression-free survival (PFS) and overall survival (OS) of GBM patients undergoing surgery and concurrent chemoradiotherapy, as well as propose a nomogram for individual risk prediction based on preoperative imaging parameters and clinicopathological variables readily available in clinical practice. METHODS: We retrospectively analyzed 114 consecutive patients with GBM who underwent surgery and concurrent chemoradiotherapy at the Second Affiliated Hospital, Zhejiang University School of Medicine from January 1st, 2015, to June 1st, 2018. Twenty-four preoperative magnetic resonance imaging (MRI) parameters were extracted manually from the Picture Archiving and Communication System (PACS). Clinicopathological factors were extracted from the electronic medical record system (EMRS). Least absolute shrinkage and selection operator (LASSO) regression and Cox regression were used for feature selection and model prediction, respectively. The models were presented using nomograms, which were applied to identify the risk of recurrence and survival according to the score. The performance of the nomograms to predict PFS and OS was tested with C-statistics, calibration plots, and Kaplan-Meier curves. RESULTS: The results revealed that sex, Karnofsky performance score (KPS), O6-methylglucamine-DNA methyltransferase (MGMT) protein expression, number of adjuvant chemotherapy cycles with temozolomide (TMZ), and the MRI signature effectively predicted PFS; and sex, KPS, extent of surgery, number of TMZ cycles, and MRI signature effectively predicted OS. The nomogram revealed good discriminative ability (C-statistics: 0.81 for PFS and 0.79 for OS). In the nomogram of PFS, patients with a score greater than 122 were considered to have a high risk of recurrence. In the nomogram of OS, the cutoff score were 115 and 145, and then patients were classified as low, medium, and high risk. CONCLUSIONS: In conclusion, our nomograms can effectively predict the risk of recurrence and survival of GBM patients and thus can be a good guide for clinical practice.

2.
Pharm Dev Technol ; 26(1): 21-29, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33070673

RESUMO

Multidrug resistance (MDR) is a serious challenge in chemotherapy and also a major threat to breast cancer treatment. As an intracellular energy factory, mitochondria provide energy for drug efflux and are deeply involved in multidrug resistance. Mitochondrial targeted delivery of doxorubicin can overcome multidrug resistance by disrupting mitochondrial function. By incorporating a reactive oxygen species (ROS)-responsive hydrophobic group into the backbone structure of hyaluronic acid - a natural ligand for the highly expressed CD44 receptor on tumor surfaces, a novel ROS-responsive and CD44-targeting nano-carriers was constructed. In this study, mitochondria-targeted triphenylphosphine modified-doxorubicin (TPP-DOX) and amphipathic ROS-responsive hyaluronic acid derivatives (HA-PBPE) were synthesized and confirmed by 1H NMR. The nanocarriers TPP-DOX @ HA-PBPE was prepared in a regular shape and particle size of approximately 200 nm. Compared to free DOX, its antitumor activity in vitro and tumor passive targeting in vivo has been enhanced. The ROS-responsive TPP-DOX@HA-PBPE nanocarriers system provide a promising strategy for the reverse of MDR and efficient delivery of doxorubicin derivatives into drug-resistant cancer cells.


Assuntos
Antineoplásicos/metabolismo , Neoplasias da Mama/metabolismo , Doxorrubicina/metabolismo , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Nanopartículas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Neoplasias da Mama/tratamento farmacológico , Relação Dose-Resposta a Droga , Doxorrubicina/administração & dosagem , Doxorrubicina/química , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/química , Portadores de Fármacos/metabolismo , Sistemas de Liberação de Medicamentos/métodos , Resistência a Múltiplos Medicamentos/fisiologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/fisiologia , Feminino , Humanos , Células MCF-7 , Camundongos , Camundongos Nus , Nanopartículas/administração & dosagem , Nanopartículas/química , Espécies Reativas de Oxigênio/química
3.
Int J Mol Sci ; 21(14)2020 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-32659905

RESUMO

A liposomal formulation of gold nanoparticles (GNPs) and carboplatin, named LipoGold, was produced with the staggered herringbone microfluidic method. The radiosensitizing potential of LipoGold and similar concentrations of non-liposomal GNPs, carboplatin and oxaliplatin was evaluated in vitro with the human colorectal cancer cell line HCT116 in a clonogenic assay. Progression of HCT116 tumor implanted subcutaneously in NU/NU mice was monitored after an irradiation of 10 Gy combined with either LipoGold, GNPs or carboplatin injected directly into the tumor by convection-enhanced delivery. Radiosensitization by GNPs alone or carboplatin alone was observed only at high concentrations of these compounds. Furthermore, low doses of carboplatin alone or a combination of carboplatin and GNPs did not engender radiosensitization. However, the same low doses of carboplatin and GNPs administered simultaneously by encapsulation in liposomal nanocarriers (LipoGold) led to radiosensitization and efficient control of cell proliferation. Our study shows that the radiosensitizing effect of a combination of carboplatin and GNPs is remarkably more efficient when both compounds are simultaneously delivered to the tumor cells using a liposomal carrier.


Assuntos
Neoplasias Colorretais/terapia , Ouro/administração & dosagem , Lipossomos/administração & dosagem , Nanopartículas Metálicas/administração & dosagem , Compostos Organoplatínicos/farmacologia , Radiossensibilizantes/administração & dosagem , Animais , Carboplatina/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Quimiorradioterapia/métodos , Portadores de Fármacos/administração & dosagem , Células HCT116 , Humanos , Masculino , Camundongos , Camundongos Nus , Oxaliplatina/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
4.
Front Oncol ; 10: 615368, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33692942

RESUMO

Radiotherapy is an important treatment for glioblastoma (GBM), but there is no consensus on the target delineation for GBM radiotherapy. The Radiation Therapy Oncology Group (RTOG) and European Organisation for Research and Treatment of Cancer (EORTC) each have their own rules. Our center adopted a target volume delineation plan based on our previous studies. This study focuses on the recurrence pattern of GBM patients whose target delineations did not intentionally include the T2/fluid-attenuated inversion recovery (FLAIR) hyperintensity area outside of the gross tumor volume (GTV). We prospectively collected 162 GBM cases and retrospectively analysed the clinical data and continuous dynamic magnetic resonance images (MRI) of 55 patients with recurrent GBM. All patients received concurrent radiotherapy and chemotherapy with temozolomide (TMZ). The GTV that we defined includes the postoperative T1-weighted MRI enhancement area and resection cavity. Clinical target volume 1 (CTV1) and CTV2 were defined as GTVs with 1 and 2 cm margins, respectively. Planning target volume 1 (PTV1) and PTV2 were defined as CTV1 and CTV2 plus a 3 mm margin with prescribed doses of 60 and 54 Gy, respectively. The first recurrent contrast-enhanced T1-weighted MRI was introduced into the Varian Eclipse radiotherapy planning system and fused with the original planning computed tomography (CT) images to determine the recurrence pattern. The median follow-up time was 15.8 months. The median overall survival (OS) and progression-free survival (PFS) were 17.7 and 7.0 months, respectively. Among the patients, 44 had central recurrences, two had in-field recurrences, one had marginal recurrence occurred, 11 had distant recurrences, and three had subependymal recurrences. Five patients had multiple recurrence patterns. Compared to the EORTC protocol, target delineation that excludes the adjacent T2/FLAIR hyperintensity area reduces the brain volume exposed to high-dose radiation (P = 0.000) without an increased risk of marginal recurrence. Therefore, it is worthwhile to conduct a clinical trial investigating the feasibility of intentionally not including the T2/FLAIR hyperintensity region outside of the GTV.

5.
J Oncol ; 2019: 9342796, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31428153

RESUMO

Malignant gliomas are undifferentiated or anaplastic gliomas. They remain incurable with a multitude of modalities, including surgery, radiation, chemotherapy, and alternating electric field therapy. Convection-enhanced delivery (CED) is a local treatment that can bypass the blood-brain barrier and increase the tumor uptake of therapeutic agents, while decreasing exposure to healthy tissues. Considering the multiple choices of drugs with different antitumor mechanisms, the supra-additive effect of concomitant radiation and chemotherapy, CED appears as a promising modality for the treatment of brain tumors. In this review, the CED-related toxicities are summarized and classified into immediate, early, and late side effects based on the time of onset, and local and systemic toxicities based on the location of toxicity. The efficacies of CED of various therapeutic agents including targeted antitumor agents, chemotherapeutic agents, radioisotopes, and immunomodulators are covered. The phase III trial PRECISE compares CED of IL13-PE38QQR, an interleukin-13 conjugated to Pseudomonas aeruginosa exotoxin A, to Gliadel® Wafer, a polymer loaded with carmustine. However, in this case, CED had no significant median survival improvement (11.3 months vs. 10 months) in patients with recurrent glioblastomas. In phase II studies, CED of recombinant poliovirus (PVSRIPO) had an overall survival of 21% vs. 14% for the control group at 24 months, and 21% vs. 4% at 36 months. CED of Tf-diphtheria toxin had a response rate of 35% in recurrent malignant gliomas patients. On the other hand, the TGF-ß2 inhibitor Trabedersen, HSV-1-tk ganciclovir, and radioisotope 131I-chTNT-1/B mAb had a limited response rate. With this treatment, patients who received CED of the chemotherapeutic agent paclitaxel and immunomodulator, oligodeoxynucleotides containing CpG motifs (CpG-ODN), experienced intolerable toxicity. Toward the end of this article, an ideal CED treatment procedure is proposed and the methods for quality assurance of the CED procedure are discussed.

6.
BMC Cancer ; 18(1): 1290, 2018 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-30587150

RESUMO

BACKGROUND: Estrogen receptor (ER) expression is important for treatment selection and prognostication of breast cancer patients. Although the metastases are the main targets of endocrine therapy, ER status is often based on the primary tumor. However, ER expression in breast cancer primary lesion may not match with its synchronous metastatic lesions in some cases. In this study, we analyzed ER expression concordance between breast cancer primary tumor and metastatic lesions. METHODS: Paraffin blocks of 100 primary breast invasive ductal carcinoma cases with axillary lymph node metastases were collected. Five tissue cores were punched out from individual primary breast cancer, and one tissue core from each lymph node metastases to assemble tissue microarrays for ER staining. Samples were then scored as 0, 1+, 2+, and 3+ according to the number and intensity of ER stained tumor cells. RESULTS: For cases with ER 3+ (strong expression) in all cores of primary lesions (n = 38), ER expression in metastatic lymph node was found in 94.7% of the patients. 91.0% of the metastatic lymph nodes were ER positive, and 84.3% of them to be 3+. Among the 46 cases of ER negative expression in all cores of primary lesions, 39 of them had all the metastatic nodes being ER negative, and ER negative nodes were seen in 95.7% of the metastases. As for 16 cases of ER inconsistent expression in primary lesions, 4 cases showed negative ER expression in all metastatic nodes, 2 cases displayed diffuse consistent ER 3+ expression, and 10 cases displayed variant ER expression. CONCLUSIONS: The findings suggest that ER expression concordance between breast cancer primary lesion and its matched metastatic lesions could be estimated by primary tumor ER expression pattern.


Assuntos
Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Metástase Linfática/patologia , Receptores de Estrogênio/metabolismo , Axila , Biópsia , Mama/patologia , Mama/cirurgia , Neoplasias da Mama/cirurgia , Carcinoma Ductal de Mama/cirurgia , Feminino , Humanos , Linfonodos/patologia , Mastectomia , Pessoa de Meia-Idade , Receptores de Estrogênio/análise , Análise Serial de Tecidos
7.
J Nanobiotechnology ; 16(1): 77, 2018 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-30290821

RESUMO

BACKGROUND: Effectiveness of chemotherapy for treating glioblastoma (GBM) brain tumors is hampered by the blood-brain barrier which limits the entry into the brain of most drugs from the blood. To bypass this barrier, convection-enhanced delivery (CED) was proposed to directly inject drugs in tumor. However, the benefit of CED may be hampered when drugs diffuse outside the tumor to then induce neurotoxicity. Encapsulation of drugs into liposome aims at increasing tumor cells specificity and reduces neurotoxicity. However, the most appropriate liposomal formulation to inject drugs into brain tumor by CED still remains to be determined. In this study, four liposomal carboplatin formulations were prepared and tested in vitro on F98 glioma cells and in Fischer rats carrying F98 tumor implanted in the brain. Impact of pegylation on liposomal surface and relevance of positive or negative charge were assessed. RESULTS: The cationic non-pegylated (L1) and pegylated (L2) liposomes greatly improved the toxicity of carboplatin in vitro compared to free carboplatin, whereas only a modest improvement and even a reduction of efficiency were measured with the anionic non-pegylated (L3) and the pegylated (L4) liposomes. Conversely, only the L4 liposome significantly increased the median survival time of Fisher rats implanted with the F98 tumor, compared to free carboplatin. Neurotoxicity assays performed with the empty L4' liposome showed that the lipid components of L4 were not toxic. These results suggest that the positive charge on liposomes L1 and L2, which is known to promote binding to cell membrane, facilitates carboplatin accumulation in cancer cells explaining their higher efficacy in vitro. Conversely, negatively charged and pegylated liposome (L4) seems to diffuse over a larger distance in the tumor, and consequently significantly increased the median survival time of the animals. CONCLUSIONS: Selection of the best liposomal formulation based on in vitro studies or animal model can result in contradictory conclusions. The negatively charged and pegylated liposome (L4) which was the less efficient formulation in vitro showed the best therapeutic effect in animal model of GBM. These results support that relevant animal model of GBM must be considered to determine the optimal physicochemical properties of liposomal formulations.


Assuntos
Carboplatina/administração & dosagem , Carboplatina/uso terapêutico , Convecção , Sistemas de Liberação de Medicamentos , Glioma/tratamento farmacológico , Injeções , Animais , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Sobrevivência Celular , Glioma/patologia , Estimativa de Kaplan-Meier , Dose Letal Mediana , Lipossomos/ultraestrutura , Ratos Endogâmicos F344
8.
Phys Chem Chem Phys ; 20(36): 23403-23413, 2018 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-30178785

RESUMO

In the present study, we consider the self-regulated generation of spatially homogeneous low density plasma (LDP) micro-channels as a high intensity ionization source arising from the multi-filamentation of powerful femtosecond (fs) laser pulses in aqueous solutions. We investigate the modulation of the femtosecond laser multiple filamentation for tuning the size of gold nanoparticles (AuNPs) synthesized in an irradiated gold chloride solution. Previous studies on the radiation-induced synthesis of colloidal gold by more conventional ionization sources, such as high energy γ-rays and electron beams, highlighted the dependence of the size distribution of AuNPs on the density of energy deposited per unit of time, i.e. the dose rate. The present method of laser-induced production of AuNPs rests on a similar radiation-assisted process, i.e. the reduction of the solvated trivalent gold ions by the hydrated electrons produced upon ionization of water. We find that trivial optical manipulation varies the rate of deposited energy by laser irradiation, which can be considered equivalent to a variation of the dose rate. We investigate the influence of varying the density of energy deposited on the laser-induced gold cluster size distribution and made a comparison with the high energy radiation-induced synthesis of AuNPs. Here, our results highlight that the present method of laser irradiation, in the regime of LDP generation, mimics the radiolysis of water at an adjustable high dose rate. More generally, these spatially and temporally resolved plasmas could be developed as a tool for the unprecedented control of chemistry under ionizing radiation.

9.
Int J Nanomedicine ; 12: 4129-4146, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28615941

RESUMO

Copper diethyldithiocarbamate (Cu(DDC)2) is the active anticancer agent generated when disulfiram (DSF) is provided in the presence of copper. To date, research directed toward repurposing DSF as an anticancer drug has focused on administration of DSF and copper in combination, efforts that have proven unsuccessful in clinical trials. This is likely due to the inability to form Cu(DDC)2 at relevant concentrations in regions of tumor growth. Little effort has been directed toward the development of Cu(DDC)2 because of the inherent aqueous insolubility of the complex. Here, we describe an injectable Cu(DDC)2 formulation prepared through a method that involves synthesis of Cu(DDC)2 inside the aqueous core of liposomes. Convection-enhanced delivery of a Cu(DDC)2 formulation prepared using 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC)/cholesterol liposomes into a rat model of F98 glioma engendered a 25% increase in median survival time relative to vehicle-treated animals. In a murine subcutaneous MV-4-11 model, treatment resulted in a 45% reduction in tumor burden when compared to controls. Pharmacokinetic studies indicated that the Cu(DDC)2 was rapidly eliminated after intravenous administration while the liposomes remained in circulation. To test whether liposomal lipid composition could increase Cu(DDC)2 circulation lifetime, a number of different formulations were evaluated. Studies demonstrated that liposomes composed of DSPC and 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-n-(carboxy[polyethylene glycol]-2000) (95:5) enhanced Cu(DDC)2 concentrations in the circulation as reflected by a 4.2-fold increase in plasma AUC(0-∞) relative to the DSPC/cholesterol formulation. The anticancer activity of this Cu(DDC)2 formulation was subsequently evaluated in the MV-4-11 model. At its maximum tolerated dose, this formulation exhibited comparable activity to the DSPC/cholesterol formulation. This is the first report demonstrating the therapeutic effects of an injectable Cu(DDC)2 formulation in vivo.


Assuntos
Antineoplásicos/administração & dosagem , Cobre/administração & dosagem , Ditiocarb/administração & dosagem , Lipossomos/química , Animais , Antineoplásicos/química , Antineoplásicos/farmacocinética , Linhagem Celular Tumoral , Colesterol/química , Cobre/química , Cobre/farmacocinética , Ditiocarb/química , Ditiocarb/farmacocinética , Composição de Medicamentos , Injeções Intravenosas , Masculino , Dose Máxima Tolerável , Camundongos , Neoplasias/tratamento farmacológico , Fosfatidilcolinas/química , Polietilenoglicóis/química , Ratos Endogâmicos F344 , Ensaios Antitumorais Modelo de Xenoenxerto
10.
Phys Chem Chem Phys ; 19(11): 7897-7909, 2017 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-28262861

RESUMO

The "cold" low density plasma channels generated by the filamentation of powerful femtosecond laser pulses in aqueous solutions constitute a source of dense ionization. Here, we probed the radiation-assisted chemistry of water triggered by laser ionization via the radical-mediated synthesis of nanoparticles in gold chloride aqueous solutions. We showed that the formation of colloidal gold originates from the reduction of trivalent ionic gold initially present in solution by the reactive radicals (e.g. hydrated electrons) produced upon the photolysis of water. We analyzed both the reaction kinetics of the laser-induced hydrated electrons and the growth kinetics of the gold nanoparticles. Introduction of radical scavengers into the solutions and different initial concentrations of gold chloride provided information about the radical-mediated chemistry. The dense ionization results in the second order cross-recombination of the photolysis primary byproducts. Competition with recombination imposes the non-homogeneous interaction of reactive radicals with solute present in irradiated aqueous solutions. Such a laser-induced non-homogeneous chemistry suggests similarities with the radiation chemistry of water exposed to conventional densely ionizing radiation (high dose rate, high linear energy transfer).

11.
Int J Nanomedicine ; 11: 5323-5333, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27789945

RESUMO

The potential of gold nanoparticles (GNPs) as radiosensitizers for the treatment of malignant tumors has been limited by the large quantities of GNPs that must be administered and the requirement for low-energy X-ray irradiation to optimize radiosensitization. In this study, we enhance the radiosensitivity of HCT116 human colorectal cells with tiopronin-coated GNPs (Tio-GNPs) combined with a low-energy X-ray (26 keV effective energy) source, similar to the Papillon 50 clinical irradiator used for topical irradiation of rectal tumors. Sensitizer enhancement ratios of 1.48 and 1.69 were measured in vitro, when the HCT116 cells were incubated with 0.1 mg/mL and 0.25 mg/mL of Tio-GNPs, respectively. In nude mice bearing the HCT116 tumor, intra-tumoral (IT) injection of Tio-GNPs allowed a 94 times higher quantity of Tio-GNPs to accumulate than was possible by intravenous injection and facilitated a significant tumor response. The time following irradiation, for tumors growing to four times their initial tumor volume (4Td) was 54 days for the IT injection of 366.3 µg of Tio-GNPs plus 10 Gy, compared to 37 days with radiation alone (P=0.0018). Conversely, no significant improvement was obtained when GNPs were injected intravenously before tumor irradiation (P=0.6547). In conclusion, IT injection of Tio-GNPs combined with low-energy X-rays can significantly reduce the growth of colorectal tumors.


Assuntos
Neoplasias Colorretais/radioterapia , Ouro/química , Nanopartículas Metálicas/administração & dosagem , Radiossensibilizantes/administração & dosagem , Animais , Neoplasias Colorretais/tratamento farmacológico , Quebras de DNA de Cadeia Dupla/efeitos dos fármacos , Quebras de DNA de Cadeia Dupla/efeitos da radiação , Células HCT116/efeitos dos fármacos , Células HCT116/efeitos da radiação , Humanos , Injeções Intralesionais , Masculino , Nanopartículas Metálicas/química , Nanopartículas Metálicas/uso terapêutico , Camundongos Nus , Radiossensibilizantes/química , Tiopronina/química , Raios X , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Int J Radiat Biol ; 92(8): 444-50, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27121902

RESUMO

PURPOSE: Irradiation of brain stimulates the expression of inflammatory mediators, some of which can modify the ability of cancer cells to infiltrate the brain. In the present study, the time window during which this stimulation occurs was determined. MATERIALS AND METHODS: Brain of Fischer rat was irradiated (15 Gy) and expression of pro-inflammatory mediators IL-1ß, IL-6 and TNF-α was measured from 4 h to 20 days post-irradiation. Level of the matrix metalloproteinase 2 (MMP-2) and prostaglandin E2 (PGE2) which can favor cancer cell infiltration were also measured. The F98 glioma cells were implanted either during (4 h post-irradiation) or after (10 days post-irradiation) the pro-inflammatory phase. Infiltration distance of F98 cells in brain parenchyma and the median survival time of the animals were determined. RESULTS: Expression of IL-1ß, IL-6 and TNF-α was significantly increased in the irradiated brains with a peak at 4 h post-irradiation. Implantation of F98 glioma cells 4 h post-irradiation reduced the median survival time of Fischer rats to 18 days, compared to 25 days when the F98 were implanted in non-irradiated brain. Irradiation of the brain increased the distance of infiltration of F98 cells and was associated with increased levels of MMP-2 and PGE2. Conversely, F98 cells implanted 10 days post-irradiation have infiltrated the brain over a shorter distance and the median survival time of rats was increased to 35 days. CONCLUSIONS: Cancer recurrence is frequently observed in GBM patients. A better understanding of the inflammatory response observed in irradiated brain could contribute to develop new therapeutic modalities to further increase the efficiency of radiotherapy.


Assuntos
Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/radioterapia , Irradiação Craniana/efeitos adversos , Glioma/patologia , Glioma/radioterapia , Neoplasias Induzidas por Radiação/patologia , Animais , Neoplasias Encefálicas/imunologia , Linhagem Celular Tumoral , Relação Dose-Resposta à Radiação , Glioma/imunologia , Masculino , Invasividade Neoplásica/imunologia , Invasividade Neoplásica/patologia , Neoplasias Induzidas por Radiação/etiologia , Neoplasias Induzidas por Radiação/imunologia , Dosagem Radioterapêutica , Ratos , Ratos Endogâmicos F344 , Taxa de Sobrevida , Resultado do Tratamento
13.
Invest New Drugs ; 34(3): 269-76, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26961906

RESUMO

Results of clinical trials with oxaliplatin in treating glioblastoma are dismal. Previous works showed that intravenous (i.v.) delivery of oxaliplatin did not increase the survival of F98 glioma-bearing Fisher rats. Low accumulation of the drug in tumor cells is presumed to be responsible for the lack of antitumor effect. In the present study, convection-enhanced delivery (CED) was used to directly inject oxaliplatin in brain tumor implanted in rats. Since CED can led to severe toxicity, the liposomal formulation of oxaliplatin (Lipoxal™) was also assessed. The maximum tolerated dose (MTD) of oxaliplatin was 10 µg, while that of Lipoxal™ was increased by 3-times reaching 30 µg. Median survival time (MeST) of F98 glioma-bearing rats injected with 10 µg oxaliplatin by CED was 31 days, 7.5 days longer than untreated control (p = 0.0002); while CED of 30 µg Lipoxal™ reached the same result. Compared to previous study on i.v. delivery of these drugs, their injection by CED significantly increased their tumoral accumulations as well as MeSTs in the F98 glioma bearing rat model. The addition of radiotherapy (15 Gy) to CED of oxaliplatin or Lipoxal™ increased the MeST by 4.0 and 3.0 days, respectively. The timing of radiotherapy (4 h or 24 h after CED) produced similar results. However, the treatment was better tolerated when radiotherapy was performed 24 h after CED. In conclusion, a better tumoral accumulation was achieved when oxaliplatin and Lipoxal™ were injected by CED. The liposomal encapsulation of oxaliplatin reduced its toxic, while maintaining its antitumor potential.


Assuntos
Antineoplásicos/administração & dosagem , Neoplasias Encefálicas/tratamento farmacológico , Glioma/tratamento farmacológico , Compostos Organoplatínicos/administração & dosagem , Animais , Antineoplásicos/efeitos adversos , Antineoplásicos/farmacologia , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/radioterapia , Terapia Combinada , Sistemas de Liberação de Medicamentos , Glioma/patologia , Glioma/radioterapia , Lipossomos , Masculino , Dose Máxima Tolerável , Compostos Organoplatínicos/efeitos adversos , Compostos Organoplatínicos/farmacologia , Oxaliplatina , Ratos , Ratos Endogâmicos F344 , Taxa de Sobrevida , Fatores de Tempo
14.
Invest New Drugs ; 33(3): 555-63, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25784204

RESUMO

The prognosis for patients with glioblastoma remains poor with current treatments. Although platinum-based drugs are sometimes offered at relapse, their efficacy in this setting is still disputed. In this study, we use convection-enhanced delivery (CED) to deliver the platinum-based drugs (cisplatin, carboplatin, and Lipoplatin(TM) - liposomal formulation of cisplatin) directly into the tumor of F98 glioma-bearing rats that were subsequently treated with γ radiation (15 Gy). CED increased by factors varying between 17 and 111, the concentration of these platinum-based drugs in the brain tumor compared to intra-venous (i.v.) administration, and by 9- to 34-fold, when compared to intra-arterial (i.a.) administration. Furthermore, CED resulted in a better systemic tolerance to platinum drugs compared to their i.a. injection. Among the drugs tested, carboplatin showed the highest maximum tolerated dose (MTD). Treatment with carboplatin resulted in the best median survival time (MeST) (38.5 days), which was further increased by the addition of radiotherapy (54.0 days). Although the DNA-bound platinum adduct were higher at 4 h after CED than 24 h for carboplatin group, combination with radiotherapy led to similar improvement of median survival time. However, less toxicity was observed in animals irradiated 24 h after CED-based chemotherapy. In conclusion, CED increased the accumulation of platinum drugs in tumor, reduced the toxicity, and resulted in a higher median survival time. The best treatment was obtained in animals treated with carboplatin and irradiated 24 h later.


Assuntos
Cisplatino/uso terapêutico , Convecção , Sistemas de Liberação de Medicamentos , Glioma/tratamento farmacológico , Glioma/radioterapia , Platina/uso terapêutico , Animais , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Cisplatino/efeitos adversos , Terapia Combinada , Modelos Animais de Doenças , Dose Máxima Tolerável , Platina/efeitos adversos , Ratos Endogâmicos F344 , Reprodutibilidade dos Testes , Análise de Sobrevida , Testes de Toxicidade Aguda
15.
Oncol Lett ; 3(3): 599-606, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22740959

RESUMO

TP53 codon 72 polymorphism has been reported to affect regulatory networks central to glioma development. Although a number of published studies noted the association between TP53 codon 72 polymorphism and glioma risk, their conclusions were inconsistent. A meta-analysis was used to assess the possible association between TP53 codon 72 polymorphism and glioma risk. The PubMed databases were searched, relevant articles were identified and data were retrieved based on the inclusion criteria. The odds ratio (OR) and 95% confidence interval (95% CI) were determined on the pooled dataset. We retrieved eight different studies including 2,260 glioma cases and 3,506 controls. However, no association was found between the TP53 codon 72 polymorphism and glioma risk regarding the comparison between glioma cases and the controls. By further stratification based on criteria such as tumor grade, and the geographical location of the patients and the relevant controls, we found a significant association in the subgroup of patients with high-grade glioma in Europeans compared to controls in two models of TP53 codon 72 polymorphism, which include the dominant model [C/C + G/C vs. G/G: OR=1.35, 95% CI (1.14, 1.59), P=0.0005, P(h)=0.13] and the additive model [C allele vs. G allele: OR=1.16, 95% CI (1.02, 1.33), P=0.03, P(h)=0.37]. Our analysis suggests that TP53 codon 72 polymorphism is associated with an increased risk of high-grade glioma development in Europeans.

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