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2.
Purinergic Signal ; 19(4): 685-697, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36854856

RESUMO

It has been demonstrated that the ATP-gated ion channel P2X7 receptor is involved in tumor progression and plays an important role in regulating tumor cell growth, invasion, migration and angiogenesis. However, P2X7 receptors have been relatively poorly studied in non-small cell lung cancer (NSCLC) cells. Therefore, the aim of this study was to investigate the effects of P2X7 receptor on A549 cells (NSCLC cell line) migration and invasion and to reveal the molecular mechanisms mediated by it. We detected the expression and function of P2X7 receptor in A549 cells. The effects and mechanisms of P2X7 receptor on A549 cells migration, invasion, and epithelial-mesenchymal transition were detected in vitro and in vivo. The results showed P2X7 receptor expressed by A549 cells had ion channel and macropore formation function. In addition, activation of P2X7 receptor by adenosine triphosphate (ATP) or 2'(3')-O-(4-Benzoylbenzoyl)-adenosine-5'-triphosphate (BzATP) promoted Epithelial-mesenchymal transition (EMT), migration and invasion of A549 cells, which was attenuated by treatment of cells with P2X7 receptor antagonist A438079 and Oxidized ATP. Furthermore, activation of P2X7 receptor increased phosphorylated protein kinase B (p-Akt) levels, and the phosphatidylinositol-tris-phosphate kinase 3 (PI3K)/protein kinase B (Akt) inhibitor LY294002 blocked migration and invasion of A549 cells induced by ATP or BzATP. At the same time, in vivo results showed that P2X7 receptor could also promote EMT and PI3K/Akt expression in transplanted tumors. Our study indicated that P2X7 receptor promotes A549 cells migration and invasion through the PI3K/Akt signaling pathway, suggesting that P2X7 receptor may be a potential therapeutic target for NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Células A549 , Trifosfato de Adenosina/farmacologia , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Neoplasias Pulmonares/metabolismo , Fosfatos/metabolismo , Fosfatos/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-akt/farmacologia , Receptores Purinérgicos P2X7
3.
Reprod Sci ; 30(3): 823-834, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-35799022

RESUMO

Cervical cancer is one of the most common and serious tumors in women. Finding new biomarkers and therapeutic targets plays an important role in the diagnosis, prognosis, and treatment of cervical cancer. Purinergic ligand-gated ion channel 7 receptor (P2X7R) is a purine ligand cation channel, activated by adenosine triphosphate (ATP). Studies have shown that P2X7R plays an important role in a variety of diseases and cancers. More and more studies have shown that P2X7R is also closely related to cervical cancer; therefore, the role of P2X7R in the development of cervical cancer deserves further discussion. The expression level of P2X7R in uterine epithelial cancer tissues was lower than that of the corresponding normal tissues. P2X7R plays an important role in the apoptotic process of cervical cancer through various mechanisms of action, and both antagonists and agonists of P2X7R can inhibit the proliferation of cervical cancer cells, while P2X7R is involved in the antitumor effect of Atr-I on cervical cancer cells. This review evaluates the current role of P2X7R in cervical cancer in order to develop more specific therapies for cervical cancer. In conclusion, P2X7R may become a biomarker for cervical cancer screening, and even a new target for clinical treatment of cervical cancer.


Assuntos
Neoplasias do Colo do Útero , Humanos , Feminino , Neoplasias do Colo do Útero/tratamento farmacológico , Detecção Precoce de Câncer , Colo do Útero/metabolismo , Biomarcadores , Apoptose , Receptores Purinérgicos P2X7 , Trifosfato de Adenosina/metabolismo , Antagonistas do Receptor Purinérgico P2X/farmacologia , Antagonistas do Receptor Purinérgico P2X/uso terapêutico
4.
Mol Biol Rep ; 50(2): 1687-1699, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36417079

RESUMO

Purinergic ligand-gated ion channel 7 receptor (P2X7R) is a nonselective cation channel of the purinergic receptor family. P2X7R is activated by adenosine triphosphate (ATP) and plays a significant role in inflammatory and autoimmune diseases by triggering cellular signal transduction. More importantly, P2X7R is abnormally expressed in many tumor cells and is involved in the progression of various tumor cells. Studies have shown that the irregular expression of P2X7R in colorectal cancer (CRC) can not only indirectly affect the occurrence and development of CRC by promoting inflammatory bowel disease but also directly affect the proliferation and metastasis of CRC cells. P2X7R plays a bidirectional role in cancer induction and inhibition by mediating complex signaling pathways in CRC, and its expression level is closely related to the overall survival of CRC patients. Therefore, P2X7R may be a biomarker and potential therapeutic target for the development and prognosis of CRC. In this paper, we review the research progress on P2X7R in CRC.


Assuntos
Neoplasias Colorretais , Receptores Purinérgicos P2X7 , Humanos , Trifosfato de Adenosina , Biomarcadores , Carcinogênese , Neoplasias Colorretais/metabolismo , Receptores Purinérgicos P2X7/genética , Receptores Purinérgicos P2X7/metabolismo , Transdução de Sinais
5.
Chem Biol Drug Des ; 101(3): 794-808, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36403102

RESUMO

Purinergic ligand-gated ion channel 7 receptor (P2X7 receptor) is an adenosine triphosphate (ATP)-gated ion channel that is widely distributed on the surfaces of immune cells and tissues such as those in the liver, kidney, lung, intestine, and nervous system. Hepatocellular carcinoma (HCC) is one of the most common malignancies with increasing incidence and mortality. Although many treatments for liver cancer have been studied, the prognosis for liver cancer is still very poor. Therefore, new liver cancer treatments are urgently needed. P2X7 receptor activation can secrete proinflammatory factors through the P2X7 receptor-NLRP3 signaling pathway, thereby affecting the progression of liver injury. The P2X7 receptor may be a target for growth inhibition of HCC cells and may affect the invasion and migration of HCC cells through the PI3K/AKT and AMPK signaling pathways. In recent years, P2X7 receptor antagonists or inhibitors have attracted widespread attention as therapeutic targets for hepatocellular carcinoma and liver injury. Therefore, this review covers the basic concepts of the P2X7 receptor and role of the P2X7 receptor in liver cancer and liver injury, providing new potential therapeutic targets for hepatocellular carcinoma and liver injury.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Receptores Purinérgicos P2X7 , Neoplasias Hepáticas/patologia , Fosfatidilinositol 3-Quinases/metabolismo , Trifosfato de Adenosina/metabolismo
6.
Sci Rep ; 12(1): 21886, 2022 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-36535979

RESUMO

Hepatocellular carcinoma (HCC) is an aggressive liver cancer with limited effective treatment options. In this study, we selected TLR agonists imiquimod (IMQ), gardiquimod (GARD), GS-9620 and DSR 6434, and a small molecule checkpoint inhibitor, BMS-202, for characterization of drug loading and release from radiopaque embolic beads (DC Bead LUMI) for potential use in image-guided transarterial embolization (TACE) of HCC. The maximum drug loading capacity and amount of drug released over time were determined by high performance liquid chromatography and compared with the commonly used anthracycline, doxorubicin hydrochloride (Dox). Maximum drug loading was 204.54 ± 3.87, 65.28 ± 3.09, 65.95 ± 6.96, 65.97 ± 1.54, and 148.05 ± 2.24 mg of drug per milliliter of DC Bead LUMI for Dox, GARD, DSR 6434, IMQ, and BMS-202, respectively. Fast loading and subsequent rapid release in saline were observed for IMQ, GARD, and DSR 6434. These drugs could also be partially removed from the beads by repeated washing with de-ionized water suggesting weak interaction with the beads. Aggregation of IMQ was observed in water and saline. GS-9620 partially decomposed in the solubilizing solution, so loading and release were not characterized. Compared to TLR agonists, slower loading and release were observed for Dox and BMS-202. Potential factors influencing drug loading into and release from DC Bead LUMI including steric hinderance, hydrophobicity, drug pKa, and the electrostatic nature of the beads are discussed. The maximum loading capacity of BMS-202 and Dox in DC Bead LUMI exceeded the maximum theoretical loading capacity of the beads expected from ionic interaction alone suggesting additional drug-bead or drug-drug interactions may play a role. Slightly more release was observed for BMS-202 at early time points followed by a slower release compared to Dox. Further study of these drug-bead combinations is warranted in search of new tools for locoregional delivery of immune-modulating agents for treatment of HCC via drug-eluting bead chemoembolization.


Assuntos
Carcinoma Hepatocelular , Quimioembolização Terapêutica , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/terapia , Neoplasias Hepáticas/terapia , Quimioembolização Terapêutica/métodos , Doxorrubicina/química , Antibióticos Antineoplásicos/química , Microesferas
7.
Front Pharmacol ; 13: 928419, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35873566

RESUMO

Breast cancer (BC) and thyroid cancer (TC) have the highest rate of incidence, especially in women. Previous studies have revealed that lactate provides energetic and anabolic support to cancer cells, thus serving as an important oncometabolite with both extracellular and intracellular signaling functions. However, the correlation of lactate metabolism scores with thyroid and breast cancer immune characteristics remains to be systematically analyzed. To investigate the role of lactate at the transcriptome level and its correlation with the clinical outcome of BC and TC, transcriptome data of 1,217 patients with breast cancer (BC) and 568 patients with thyroid cancer (TC) were collected from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) datasets with their corresponding clinical and somatic mutation data. The lactate metabolism score was calculated based on a single-sample gene set enrichment analysis (ssGSEA). The results showed that lactate metabolism-related genes and lactate metabolism scores was significantly associated with the survival of patients with BRCA and THCA. Notably, the lactate metabolism scores were strongly correlated with human leukocyte antigen (HLA) expression, tumor-infiltrating lymphocyte (TIL) infiltration, and interferon (IFN) response in BC and TC. Furthermore, the lactate metabolism score was an independent prognostic factor and could serve as a reliable predictor of overall survival, clinical characteristics, and immune cell infiltration, with the potential to be applied in immunotherapy or precise chemotherapy of BC and TC.

8.
Hum Cell ; 35(5): 1346-1354, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35657562

RESUMO

Prostate cancer is the most common malignancy of the male genitourinary system and is one of the leading causes of male cancer death. The P2X7 receptor is an important member of purine receptor family. It is a gated ion channel with adenosine triphosphate (ATP) as the ligand, which exists in a variety of immune tissues and cells and can be involved in tumorigenesis and tumor progression. Studies have shown that the P2X7 receptor is abnormally expressed in prostate cancer, and is related to the level of prostate-specific antigen, P2X7 receptor may be an early biomarker of prostate cancer. The P2X7 receptor is essential in the occurrence and development of prostate cancer. The P2X7 receptor mainly affects the invasion and metastasis of prostate cancer cells through epithelial mesenchymal transition/invasion-related genes and the PI3K/AKT and ERK1/2 signaling pathways. The P2X7 receptor could be a promising therapeutic target for prostate cancer.


Assuntos
Trifosfato de Adenosina , Neoplasias da Próstata , Receptores Purinérgicos P2X7 , Trifosfato de Adenosina/metabolismo , Humanos , Masculino , Fosfatidilinositol 3-Quinases/metabolismo , Neoplasias da Próstata/patologia , Receptores Purinérgicos P2X7/genética , Receptores Purinérgicos P2X7/metabolismo , Transdução de Sinais/genética
9.
Eur J Pharm Sci ; 160: 105772, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33621612

RESUMO

Understanding the intra-tumoral distribution of chemotherapeutic drugs is extremely important in predicting therapeutic outcome. Tissue mimicking gel phantoms are useful for studying drug distribution in vitro but quantifying distribution is laborious due to the need to section phantoms over the relevant time course and individually quantify drug elution. In this study we compare a bespoke version of the traditional phantom sectioning approach, with a novel confocal microscopy technique that enables dynamic in situ measurements of drug concentration. Release of doxorubicin from Drug-eluting Embolization Beads (DEBs) was measured in phantoms composed of alginate and agarose over comparable time intervals. Drug release from several different types of bead were measured. The non-radiopaque DC Bead™ generated a higher concentration at the boundary between the beads and the phantom and larger drug penetration distance within the release period, compared with the radiopaque DC Bead LUMI™. This is likely due to the difference of compositional and structural characteristics of the hydrogel beads interacting differently with the loaded drug. Comparison of in vitro results against historical in vivo data show good agreement in terms of drug penetration, when confounding factors such as geometry, elimination and bead chemistry were accounted for. Hence these methods have demonstrated potential for both bead and gel phantom validation, and provide opportunities for optimisation of bead design and embolization protocols through in vitro-in vivo comparison.


Assuntos
Quimioembolização Terapêutica , Portadores de Fármacos , Doxorrubicina , Liberação Controlada de Fármacos , Microesferas
10.
Cardiovasc Intervent Radiol ; 43(12): 1918-1924, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32803282

RESUMO

PURPOSE: Topotecan is a camptothecin analogue with potential advantages over irinotecan for transarterial chemoembolization (TACE) of hepatic colorectal metastases including greater anti-neoplastic activity without enzymatic activation. The purpose of this study was to assess safety and tolerability of topotecan-loaded radiopaque microspheres (ROMTOP) administered by TACE in a rabbit model and to compare the in vitro elution of topotecan from microspheres to irinotecan. MATERIALS AND METHODS: Topotecan was loaded into radiopaque microspheres (70-150 µm, DC Bead LUMI™, Biocompatibles UK Ltd-Boston Scientific Corporation) to the maximum capacity of 80 mg/mL of microspheres. Six healthy New Zealand White rabbits underwent hepatic TACE with ROMTOP under fluoroscopic guidance until angiographic stasis. Assessment of toxicities included regular liver function tests and complete blood counts until euthanasia 28 days post-TACE. In vitro topotecan elution from the microspheres was assessed using an open-loop flow-through system and compared to irinotecan. RESULTS: The mean bead volume and topotecan dose delivered were 0.086 mL (0.076-0.105 mL) and 1.99 mg/kg (1.51-2.55 mg/kg), respectively. Aspartate aminotransferase and alanine aminotransferase were elevated post-embolization but resolved within 2 weeks. One rabbit died two days after TACE with pyloric duodenal perforation observed at necropsy, potentially due to non-target embolization. In vitro elution of topotecan from ROMTOP was complete in 10 h compared to 3 h for irinotecan-loaded microspheres. CONCLUSION: Selective embolization with ROMTOP was tolerated at a dose of 2 mg/kg (24 mg/m2) in rabbits. In vitro topotecan elution from microspheres was more prolonged compared to irinotecan.


Assuntos
Carcinoma Hepatocelular/terapia , Quimioembolização Terapêutica/métodos , Neoplasias Hepáticas Experimentais/terapia , Topotecan/farmacologia , Animais , Carcinoma Hepatocelular/diagnóstico , Humanos , Irinotecano , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas Experimentais/diagnóstico , Microesferas , Coelhos , Inibidores da Topoisomerase I/farmacologia
11.
Theranostics ; 9(19): 5626-5641, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31534507

RESUMO

There are currently two methods widely used in clinical practice to perform transarterial chemoembolization (TACE). One is based on mixing an aqueous drug with an iodized oil (Lipiodol) and creating an emulsion that is delivered intraarterially, followed by embolization with a particulate agent. The other is based on a one-step TACE using Drug-eluting Beads (DEBs) loaded with drug. It is not recommended to mix Lipiodol with DEBs due to incompatibility. For the first time, novel DEB: Lipiodol: doxorubicin (Dox) emulsions are identified using lyophilized polyvinyl alcohol (PVA) hydrogels (non-iodinated or iodinated) DEBs. METHODS: 15 DEB emulsions (50mg Dox) were assessed for stability and deliverability in vitro and in vivo in a swine model. Dox release from selected formulations was measured in vitro using a vascular flow model and in vivo in a VX2 rabbit tumor model. RESULTS: Both DEB formats were shown to be able to form emulsions, however only Iodinated DEBs consistently met defined handling criteria. Those based on the non-iodinated DEB achieved >99%+ Dox loading in <5 minutes but were generally less stable. Those prepared using iodinated DEBs, which are more hydrophobic, were able to form stable Pickering-like emulsions (separation time ≥ 20 minutes) and demonstrated handling, administration and imaging observations more akin to Lipiodol™ TACE emulsions in both embolization models. Controlled Dox release and hence beneficial in vivo pharmacokinetics associated with DEB-TACE were maintained. CONCLUSIONS: This study demonstrates that it is possible to formulate novel DEB emulsions suitable for TACE that combine positive elements of both Lipiodol™ based and DEB-TACE procedures.


Assuntos
Quimioembolização Terapêutica , Doxorrubicina/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Óleo Etiodado/química , Animais , Doxorrubicina/química , Sistemas de Liberação de Medicamentos/instrumentação , Emulsões/administração & dosagem , Emulsões/química , Óleo Etiodado/administração & dosagem , Feminino , Masculino , Coelhos , Suínos
12.
Eur J Pharm Sci ; 136: 104943, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31152772

RESUMO

Drug-eluting Embolic Bead - Transarterial Chemoembolisation (DEB-TACE) is a minimally invasive embolising treatment for liver tumours that allows local release of chemotherapeutic drugs via ion exchange, following delivery into hepatic arterial vasculature. Thus far, no single in vitro model has been able to accurately predict the complete kinetics of drug release from DEB, due to heterogeneity of rate-controlling mechanisms throughout the process of DEB delivery. In this study, we describe two in vitro models capable of distinguishing between early phase and late phase drug release by mimicking in vivo features of each phase. First, a vascular flow system (VFS) was used to simulate the early phase by delivering DEB into a silicon vascular cast under high pulsatile flow. This yielded a burst release profile of drugs from DEB which related to the dose adjusted Cmax observed in pharmacokinetic plasma profiles from a preclinical swine model. Second, an open loop flow-through cell system was used to model late phase drug release by packing beads in a column with an ultra-low flow rate. DEB loaded with doxorubicin, irinotecan and vandetanib showed differential drug release rates due to their varying chemical properties and unique drug-bead interactions. Using more representative in vitro models to map discrete phases of DEB drug release will provide a better capability to predict the pharmacokinetics of developmental formulations, which has implications for treatment safety and efficacy.


Assuntos
Doxorrubicina/farmacocinética , Liberação Controlada de Fármacos/fisiologia , Irinotecano/farmacocinética , Piperidinas/farmacocinética , Quinazolinas/farmacocinética , Animais , Quimioembolização Terapêutica/métodos , Sistemas de Liberação de Medicamentos/métodos , Técnicas In Vitro , Fígado/efeitos dos fármacos , Fígado/metabolismo , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/metabolismo , Suínos
13.
Future Oncol ; 14(26): 2741-2760, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29944007

RESUMO

This review describes the historical development of an imageable spherical embolic agent and focuses on work performed in collaboration between Biocompatibles UK Ltd (a BTG International group company) and the NIH to demonstrate radiopaque bead utility and bring a commercial offering to market that meets a clinical need. Various chemistries have been investigated and multiple prototypes evaluated in search of an optimized product with the right balance of handling and imaging properties. Herein, we describe the steps taken in the development of DC Bead LUMI™, the first commercially available radiopaque drug-eluting bead, ultimately leading to the first human experience of this novel embolic agent in the treatment of liver tumors.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Quimioembolização Terapêutica/métodos , Portadores de Fármacos/química , Desenvolvimento de Medicamentos , Neoplasias Hepáticas/terapia , Animais , Quimioembolização Terapêutica/instrumentação , Meios de Contraste/química , Modelos Animais de Doenças , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Microesferas , Tomografia Computadorizada por Raios X , Resultado do Tratamento
14.
J Control Release ; 250: 36-47, 2017 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-28188808

RESUMO

We have developed a straightforward and efficient method of introducing radiopacity into Polyvinyl alcohol (PVA)-2-Acrylamido-2-methylpropane sulfonic acid (AMPS) hydrogel beads (DC Bead™) that are currently used in the clinic to treat liver malignancies. Coupling of 2,3,5-triiodobenzaldehyde to the PVA backbone of pre-formed beads yields a uniformly distributed level of iodine attached throughout the bead structure (~150mg/mL) which is sufficient to be imaged under standard fluoroscopy and computed tomography (CT) imaging modalities used in treatment procedures (DC Bead LUMI™). Despite the chemical modification increasing the density of the beads to ~1.3g/cm3 and the compressive modulus by two orders of magnitude, they remain easily suspended, handled and administered through standard microcatheters. As the core chemistry of DC Bead LUMI™ is the same as DC Bead™, it interacts with drugs using ion-exchange between sulfonic acid groups on the polymer and the positively charged amine groups of the drugs. Both doxorubicin (Dox) and irinotecan (Iri) elution kinetics for all bead sizes evaluated were within the parameters already investigated within the clinic for DC Bead™. Drug loading did not affect the radiopacity and there was a direct relationship between bead attenuation and Dox concentration. The ability (Dox)-loaded DC Bead LUMI™ to be visualized in vivo was demonstrated by the administration of into hepatic arteries of a VX2 tumor-bearing rabbit under fluoroscopy, followed by subsequent CT imaging.


Assuntos
Antineoplásicos/administração & dosagem , Camptotecina/análogos & derivados , Doxorrubicina/administração & dosagem , Animais , Antineoplásicos/química , Benzaldeídos/química , Camptotecina/administração & dosagem , Camptotecina/química , Linhagem Celular Tumoral , Quimioembolização Terapêutica , Preparações de Ação Retardada , Doxorrubicina/química , Portadores de Fármacos , Liberação Controlada de Fármacos , Feminino , Humanos , Iodobenzenos/química , Troca Iônica , Irinotecano , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/terapia , Microesferas , Imagem Óptica , Tamanho da Partícula , Álcool de Polivinil/química , Coelhos , Propriedades de Superfície , Tomografia Computadorizada por Raios X
15.
Eur J Pharm Sci ; 93: 351-9, 2016 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-27523788

RESUMO

An improved method for evaluating drug release behaviour of drug-eluting embolization beads (DEBs) was developed utilizing an open-loop flow-through system, in which the beads were packed into an occlusive mass within the system and extracted with a flowing elution medium over time. Glass beads were introduced into the beads mass in order to ensure laminar flow, reduce dead volume and improve reproducibility by compensating for swelling phenomena. The effects of glass bead ratio, elution medium flow rate and ion concentration, DEB size and drug concentration and drug type (doxorubicin and irinotecan) were evaluated using DEB composed of a sulfonate-modified polyvinyl alcohol hydrogel (DC Bead™) as the test article. The rate and amount of drug elution from the packed beads was affected by flow rate, the bead size and initial loading dose. The raw data from the concentration profile analysis provided valuable information to reveal the drug elution behaviour akin to the pharmacokinetic data observed for embolized beads (yielding in vitro Cmax and tmax data) which was complementary to the normal cumulative data obtained. A good correlation with historical reported in vivo data validated the usefulness of the method for predicting in vivo drug elution behaviour.


Assuntos
Quimioembolização Terapêutica , Sistemas de Liberação de Medicamentos , Antibióticos Antineoplásicos/administração & dosagem , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/farmacocinética , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/química , Camptotecina/administração & dosagem , Camptotecina/análogos & derivados , Camptotecina/química , Quimioembolização Terapêutica/instrumentação , Quimioembolização Terapêutica/métodos , Doxorrubicina/administração & dosagem , Doxorrubicina/química , Doxorrubicina/farmacocinética , Liberação Controlada de Fármacos , Troca Iônica , Irinotecano , Álcool de Polivinil/química , Ácidos Sulfônicos/química
16.
J Mater Sci Mater Med ; 27(1): 13, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26676859

RESUMO

Clinical use of DC Bead™ loaded with doxorubicin (DEBDOX™) or irinotecan (DEBIRI™), for the treatment of primary and secondary tumours of the liver respectively, is showing great promise. Recently there has been a tendency to select smaller bead size ranges to treat tumours in an effort to allow more drug dose to be administered, improve tumoural penetration and resultant drug delivery and tumour coverage. Herein we describe the development and performance characterisation of a new DC Bead size range (DC BeadM1 (TM), 70-150 µm) capable of an increased bead delivery in the distal vasculature, corresponding to greater tumour coverage and drug dose delivered. Both unloaded and drug loaded DC BeadM1 were shown to have a greater density of distal volume of penetration although the ultimate distal level of penetration was the same as that of the 100-300 µm beads in an in vitro penetration model. Elution of doxorubicin was slower than irinotecan elution, but it was similar when comparing the same drug elution from 70 to 150 µm compared to 100-300 µm beads. Radiopaque versions of 70-150 and 100-300 µm beads were prepared in order to evaluate distribution ex vivo using µ-CT and doxorubicin distribution using epifluorescent microscopy. Liver distribution of the radiopaque versions of the beads was shown to be more distal and efficient at filling smaller vessels with the DC BeadM1 and correspondingly more beads were found per vessel histologically with a larger area of drug coverage with the smaller size range. This study indicates that the smaller (70-150 µm) beads should permit an increased dose of drug to be administered to both hypervascular and hypovascular tumours as compared to 100-300 µm beads.


Assuntos
Antineoplásicos/administração & dosagem , Camptotecina/análogos & derivados , Catéteres , Doxorrubicina/administração & dosagem , Portadores de Fármacos , Neoplasias Hepáticas Experimentais/tratamento farmacológico , Animais , Antineoplásicos/farmacocinética , Camptotecina/administração & dosagem , Camptotecina/farmacocinética , Doxorrubicina/farmacocinética , Irinotecano , Coelhos , Microtomografia por Raio-X
17.
Radiology ; 279(3): 741-53, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26678453

RESUMO

Purpose To assess the visibility of radiopaque microspheres during transarterial embolization (TAE) in the VX2 rabbit liver tumor model by using multimodality imaging, including single-snapshot radiography, cone-beam computed tomography (CT), multidetector CT, and micro-CT. Materials and Methods The study was approved by the institutional animal care and use committee. Fifteen VX2-tumor-bearing rabbits were assigned to three groups depending on the type of embolic agent injected: 70-150-µm radiopaque microspheres in saline (radiopaque microsphere group), 70-150-µm radiopaque microspheres in contrast material (radiopaque microsphere plus contrast material group), and 70-150-µm radiolucent microspheres in contrast material (nonradiopaque microsphere plus contrast material group). Rabbits were imaged with single-snapshot radiography, cone-beam CT, and multidetector CT. Three to 5 weeks after sacrifice, excised livers were imaged with micro-CT and histologic analysis was performed. The visibility of the embolic agent was assessed with all modalities before and after embolization by using a qualitative three-point scale score reading study and a quantitative assessment of the signal-to-noise ratio (SNR) change in various regions of interest, including the tumor and its feeding arteries. The Kruskal-Wallis test was used to compare the rabbit characteristics across groups, and the Wilcoxon signed rank test was used to compare SNR measurements before and after embolization. Results Radiopaque microspheres were qualitatively visualized within tumor feeding arteries and targeted tissue with all imaging modalities (P < .05), and their presence was confirmed with histologic examination. SNRs of radiopaque microsphere deposition increased after TAE on multidetector CT, cone-beam CT, and micro-CT images (P < .05). Similar results were obtained when contrast material was added to radiopaque microspheres, except for additional image attenuation due to tumor enhancement. For the group with nonradiopaque microspheres and contrast material, retained tumoral contrast remained qualitatively visible with all modalities except for micro-CT, which demonstrated soluble contrast material washout over time. Conclusion Radiopaque microspheres were visible with all imaging modalities and helped increase conspicuity of the tumor as well as its feeding arteries after TAE in a rabbit VX2 liver tumor model. (©) RSNA, 2015.


Assuntos
Embolização Terapêutica , Neoplasias Hepáticas Experimentais/diagnóstico por imagem , Animais , Tomografia Computadorizada de Feixe Cônico , Meios de Contraste , Óleo Etiodado , Neoplasias Hepáticas Experimentais/irrigação sanguínea , Masculino , Microesferas , Tomografia Computadorizada Multidetectores , Imagem Multimodal , Coelhos
18.
J Vasc Interv Radiol ; 27(1): 117-126.e3, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26549370

RESUMO

PURPOSE: To develop a simple method to produce radiopaque drug-eluting microspheres (drug-eluting beads [DEBs]) that could be incorporated into the current clinical transcatheter arterial chemoembolization workflow and evaluate their performance in vitro and in vivo. MATERIALS AND METHODS: An ethiodized oil (Lipiodol; Guerbet, Villepinte, France) and ethanol solution was added to a lyophilized 100-300 µm bead before loading with doxorubicin. These radiopaque drug-eluting beads (DEBs; Biocompatibles UK Ltd, Farnham, United Kingdom) were evaluated in vitro for x-ray attenuation, composition, size, drug loading and elution, and correlation between attenuation and doxorubicin concentration. In vivo conspicuity was evaluated in a VX2 tumor model. RESULTS: Lipiodol was loaded into lyophilized beads using two glass syringes and a three-way stopcock. Maximum bead attenuation was achieved within 30 minutes. X-ray attenuation of radiopaque beads increased linearly (21-867 HU) with the amount of beads (0.4-12.5 vol%; R(2) = 0.9989). Doxorubicin loading efficiency and total amount eluted were similar to DC Bead (Biocompatibles UK Ltd); however, the elution rate was slower for radiopaque DEBs (P < .05). Doxorubicin concentration linearly correlated with x-ray attenuation of radiopaque DEBs (R(2) = 0. 99). Radiopaque DEBs were seen in tumor feeding arteries after administration by fluoroscopy, computed tomography, and micro-computed tomography, and their location was confirmed by histology. CONCLUSIONS: A simple, rapid method to produce radiopaque DEBs was developed. These radiopaque DEBs provided sufficient conspicuity to be visualized with x-ray imaging techniques.


Assuntos
Quimioembolização Terapêutica/instrumentação , Portadores de Fármacos , Neoplasias Hepáticas Experimentais/terapia , Microesferas , Animais , Modelos Animais de Doenças , Doxorrubicina/administração & dosagem , Óleo Etiodado/administração & dosagem , Fígado/diagnóstico por imagem , Neoplasias Hepáticas Experimentais/diagnóstico por imagem , Imagens de Fantasmas , Coelhos , Microtomografia por Raio-X
19.
J Mater Sci Mater Med ; 26(6): 198, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26105830

RESUMO

Therapeutic embolization of blood vessels is a minimally invasive, catheter-based procedure performed with solid or liquid emboli to treat bleeding, vascular malformations, and vascular tumors. Hepatocellular carcinoma (HCC) affects about half a million people per year. When unresectable, HCC is treated with embolization and local drug therapy by transarterial chemoembolization (TACE). For TACE, drug eluting beads (DC Bead(®)) may be used to occlude or reduce arterial blood supply and deliver chemotherapeutics locally to the tumor. Although this treatment has been shown to be safe and to improve patient survival, the procedure lacks imaging feedback regarding the location of embolic agent and drug coverage. To address this shortcoming, herein we report the synthesis and characterization of image-able drug eluting beads (iBeads) from the commercial DC Bead(®) product. Two different radiopaque beads were synthesized. In one approach, embolic beads were conjugated with 2,3,5-triiodobenzyl alcohol in the presence of 1,1'-carbonyldiimidazol to give iBead I. iBead II was synthesized with a similar approach but instead using a trimethylenediamine spacer and 2,3,5-triiodobenzoic acid. Doxorubicin was loaded into the iBeads II using a previously reported method. Size and shape of iBeads were evaluated using an upright microscope and their conspicuity assessed using a clinical CT and micro-CT. Bland and Dox-loaded iBeads II visualized with both clinical CT and microCT. Under microCT, individual bland and Dox loaded beads had a mean attenuation of 7904 ± 804 and 11,873.96 ± 706.12 HU, respectively. These iBeads have the potential to enhance image-guided TACE procedures by providing localization of embolic-particle and drug.


Assuntos
Quimioembolização Terapêutica/métodos , Meios de Contraste/química , Meios de Contraste/síntese química , Antineoplásicos/administração & dosagem , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/química , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/terapia , Diaminas/química , Doxorrubicina/administração & dosagem , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/terapia , Teste de Materiais , Microesferas , Imagens de Fantasmas , Álcool de Polivinil/química , Ácidos Tri-Iodobenzoicos/química , Microtomografia por Raio-X
20.
J Transl Med ; 10 Suppl 1: S4, 2012 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-23046633

RESUMO

BACKGROUND: Triple negative breast cancer (TNBC) occurs in approximately 10% to 25% of all patients with breast cancer and is associated with poor prognosis. Neo-adjuvant chemotherapy has been reported to produce a higher pathologic complete response (pCR) rate in TNBC. If pCR is achieved, patients with TNBC had a similar survival with non-TNBC patients. The aim of our study was to investigate the protein expression of epithelial growth factor receptor (EGFR) and response to neo-adjuvant chemotherapy and clinical outcome in patients with TNBC compared with non-TNBC. METHODS: A total of 198 locally advanced breast cancer patients who received neo-adjuvant chemotherapy were studied. Immunohistochemistry (IHC) was carried out to detect the protein expression of EGFR in tumor samples. Clinical and pathological parameters, pCR rate and survival data were compared between 40 TNBCs and 158 non-TNBCs. RESULTS: In 198 cases who received neo-adjuvant chemotherapy, significant differences exist in surgical therapy (P=0.005) and pCR rate (P=0.012) between patients with TNBCs and non-TNBCs. Overexpression of EGFR was significantly associated with pCR rate in patients with TNBCs (P < 0.001). Survival analysis revealed that patients with TNBCs had worse DFS and OS than those with non-TNBCs (P = 0.001, P < 0.001 respectively). Furthermore, for patients with non-TNBCs, those who achieved pCR had better DFS and OS than those who achieved RD (both P < 0.001). CONCLUSIONS: Our results suggested that patients with TNBCs had increased pCR rates compared with non-TNBC. Overexpression of EGFR predicted better response to neo-adjuvant chemotherapy in patients with TNBCs.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Receptores ErbB/metabolismo , Terapia Neoadjuvante , Adulto , Idoso , Neoplasias da Mama/patologia , Intervalo Livre de Doença , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasia Residual/tratamento farmacológico , Neoplasia Residual/metabolismo , Prognóstico , Resultado do Tratamento
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