Arming embolic beads with anti-VEGF antibodies and controlling their release using LbL technology

A Comprehensive Look at In Vitro Angiogenesis Image Analysis Software

One of the complex challenges faced presently by tissue engineering (TE) is the development of vascularized constructs that accurately mimic the extracellular matrix (ECM) of native tissue in which they are inserted to promote vessel growth and, consequently, wound healing and tissue regeneration. TE technique is characterized by several stages, starting from the choice of cell culture and the more appropriate scaffold material that can adequately support and supply them with the necessary biological cues for microvessel development. The next step is to analyze the attained microvasculature, which is reliant on the available labeling and microscopy techniques to visualize the network, as well as metrics employed to characterize it. These are usually attained with the use of software, which has been cited in several works, although no clear standard procedure has been observed to promote the reproduction of the cell response analysis. The present review analyzes not only the various steps previously described in terms of the current standards for evaluation, but also surveys some of the available metrics and software used to quantify networks, along with the detection of analysis limitations and future improvements that could lead to considerable progress for angiogenesis evaluation and application in TE research.

Explosomes: A new modality for DEB-TACE local delivery of sorafenib: In vivo proof of sustained release

The current medical practice in treating Hepatocellular carcinoma (HCC) using Drug Eluting Transarterial chemoembolization (DEB-TACE) technique is limited only to hydrophilic ionizable drugs, that can be attached ionically to the oppositely charged beads. This limitation has forced physicians to subscribe the more hydrophobic, first treatment option drugs, like sorafenib systemically via the oral route, thus flooding the patient system with a very powerful, non-specific, multiple-receptor tyrosine kinase inhibitor that is associated with notorious side effects. In this paper, a new modality is introduced, where highly charged, drug loaded liposomes are added to oppositely charged DEBs in a manner causing them to "explode" and the drug is eventually attached to the beads in the lipid patches covering their surfaces; therefore we call them "Explosomes". After fully describing the preparation process and in vitro characterization, this manuscript delves into an in vivo pharmacokinetic study over 50 New Zealand rabbits, where explosomal loading is challenged vs oral as well as current practice of emulsifying sorafenib in lipiodol. Over 14 days of follow up, and compared to other groups, explosomal loading of SRF on embolic beads proved to cause a slower release pattern with longer Tmax, lower Cmax and less washout to general circulation in healthy animals. This treatment modality opens a new untapped door for local sustained delivery of hydrophobic drugs in catheterized organs.

Bevacizumab-loaded CalliSpheres beads: in vitro loading, release profiles and application in rabbit liver VX2 tumor model

Background

Bevacizumab loaded drug-eluting beads have the potential to reduce TACE related VEGF expression. The purpose of this study was to investigate the in vitro loading, and release profiles of bevacizumab (BEV) loaded on Callispheres beads (CB) and its application in rabbit liver VX2 tumor model.

Methods

CB with sizes of 100-300 um and 300-500 um were divided into 5 groups, respectively. BEV with different content was prepared for CB loading, releasing and detected in the solution at different time points. The diameters of CB in each group were measured under a light microscope to calculate the shrinkage rate. The rabbit with VX2 liver model were divided into control group, CB-TACE group, CB-TACE+BEV group, and BEV group. The data of blood test, CT image, HE and IHC staining were compared and analyzed.

Results

The shrinkage rate of the 100-300 um CB was 2.6-7.2%, while the 300-500 um CB was 0.2-7.1%. The BEV-loaded CB (BEV-CB) has a burst release during the first hour and following gradually released with time. The release profiles of 100-300 um CB reach 34% in 24 hours, while the 300-500 um CB to 25.8%. BEV-CB with sizes of 100-300 um was chosen to perform transcatheter arterial chemoembolization (TACE). The results showed that BEV-CB-TACE not only gradually increased the content of BEV in serum and organ tissue but also reduced the level of VEGF in serum. Pathological results suggested that the expression of HIF-1 was elevated while VEGF and MVD decreased when compared to the other groups.

Conclusion

In conclusion, this study confirms that Callispheres beads could efficiency loaded BEV. BEV-CB-TACE has a good safety and effectiveness, and its application could reduce the level of VEGF-A in serum in the treatment of VX2 tumors.

Efficacy and safety analysis of TACE + sunitinib vs. sunitinib in the treatment of unresectable advanced renal cell carcinoma: a retrospective study

BACKGROUND

Since renal cell carcinoma(RCC) is insensitive to conventional chemoradiotherapy, molecularly targeted drugs are commonly used treatments for unresectable advanced RCC. The aim of this study was to explore the efficacy and safety of TACE + sunitinib vs. sunitinib in the treatment of unresectable advanced RCC.

METHODS

This study included 98 patients with unresectable advanced RCC who were treated in Union Hospital from January 2015 to December 2018, and they met the criteria. They were divided into two groups: TACE + Sunitinib group (N = 47) and Sunitinib group (N = 51). We conducted a retrospective study to analyze the efficacy and safety of the two groups of patients.

RESULTS

(1)TACE + Sunitinib group: 4 patients (8.5%) achieved CR, 27 patients (57.5%) achieved PR, 9 patients (19.1%) achieved SD, and 7 patients (14.9%) achieved PD. Sunitinib group, 0 patients (0%) achieved CR, 20 patients (39.2%) achieved PR, 14 patients (27.5%) achieved SD, and 17 patients (33.3%) achieved PD. (P = 0.017) (2)ORR: TACE + sunitinib group, 66.0%; sunitinib group, 39.2%. (P = 0.009) (3)DCR: TACE + sunitinib group, 85.1%; sunitinib group, 66.7%. (P = 0.038) (4) In the TACE + sunitinib group, mPFS was 15.6 months, mOS was 35.0 months; in the sunitinib group, the mPFS was 10.9 months, mOS was 25.7 months. (P < 0.001) (5) The incidence of abdominal pain, fever, and vomiting was higher in the TACE + sunitinib group than in the sunitinib group (abdominal pain: 55.3% vs. 13.7%; fever: 61.7% vs. 7.8%; vomiting: 40.4% vs. 19.6%; P < 0.05). The technical success rate of TACE in TACE + Sunitinib group is 100%.

CONCLUSIONS

The TACE + sunitinib group had higher ORR and DCR, longer OS and PFS than the sunitinib alone group. TACE combined with sunitinib can play a complementary role and is a safe and effective treatment for advanced RCC.

Idarubicin-loaded biodegradable microspheres enhance sensitivity to anti-PD1 immunotherapy in transcatheter arterial chemoembolization of hepatocellular carcinoma

Transarterial chemoembolization (TACE) is an image-guided locoregional therapy used for the treatment of patients with primary hepatocellular carcinoma (HCC). However, conventional TACE formulations such as epirubicin-lipiodol emulsion are rapidly dissociated due to the instability of the emulsion, resulting in insufficient local drug concentrations in the target tumor. To overcome these limitations, we used biodegradable Idarubicin loaded microspheres (BILMs), which were prepared from gelatin and carrageenan and could be loaded with Idarubicin (IDA-MS). The morphology and the ability to load and release IDA of BILMs were characterized in vitro. We evaluated tumor changes and side effects after TACE treatment with IDA-MS in VX2 rabbit and C57BL/6 mice HCC models. In addition, the effect of IDA-MS on the tumor immune microenvironment of HCC tumors was elucidated via mass spectrometry and immunohistochemistry. Result showed that IDA-MS was developed as a new TACE formulation to overcome the poor delivery of drugs due to rapid elimination of the anticancer drug into the systemic circulation. We demonstrated in rabbits and mice HCC models that TACE with IDA-MS resulted in significant tumor shrinkage and no more severe adverse events than those observed in the IDA group. TACE with IDA-MS could also significantly enhance the sensitivity of anti-PD1 immunotherapy, improve the expression of CD8⁺ T cells, and activate the tumor immune microenvironment in HCC. This study provides a new approach for TACE therapy and immunotherapy and illuminates the future of HCC treatment. STATEMENT OF SIGNIFICANCE: Conventional transarterial chemoembolization (TACE) formulations are rapidly dissociated due to the instability of the emulsion, resulting in insufficient local drug concentrations in hepatocellular carcinoma (HCC). To overcome these limitations, we used biodegradable microspheres called BILMs, which could be loaded with Idarubicin (IDA-MS). We demonstrated in rabbits and mice HCC models that TACE with IDA-MS resulted in significant tumor shrinkage and no more severe adverse events than those observed in the IDA group. TACE with IDA-MS could also significantly enhance the sensitivity of anti-PD1 immunotherapy, improve the expression of CD8⁺ T cells, and activate the tumor immune microenvironment in HCC. This study provides a new approach for TACE therapy and immunotherapy and illuminates the future of HCC treatment.

Polymersome-stabilized doxorubicin-lipiodol emulsions for high-efficacy chemoembolization therapy

Transarterial chemoembolization (TACE) with free doxorubicin-lipiodol emulsions (free DOX/L) is a favored clinical treatment for advanced hepatocellular carcinoma (HCC) patients ineligible for radical therapies; however, its inferior colloidal stability not only greatly reduces its tumor retention but also hastens drug release into blood circulation, leading to suboptimal clinical outcomes. Here, we find that disulfide-crosslinked polymersomes carrying doxorubicin (Ps-DOX) form super-stable and homogenous water-in-oil microemulsions with lipiodol (Ps-DOX/L). Ps-DOX/L microemulsions had tunable sizes ranging from 14 to 44 μm depending on the amount of Ps-DOX, were stable over 2 months storage as well as centrifugation, and exhibited nearly zero-order DOX release within 15 days. Of note, Ps-DOX induced 2.3-13.4 fold better inhibitory activity in all tested rat, murine and human liver tumor cells than free DOX likely due to its efficient redox-triggered intracellular drug release. Interestingly, transarterial administration of Ps-DOX/L microemulsions in orthotopic rat N1S1 syngeneic HCC model showed minimal systemic DOX exposure, high and long hepatic DOX retention, complete tumor elimination, effective inhibition of angiogenesis, and depleted adverse effects, significantly outperforming clinically used free DOX/L emulsions. This smart polymersome stabilization of doxorubicin-lipiodol microemulsions provides a novel TACE strategy for advanced tumors.

Donafenib-Loaded Callispheres Beads Embolization in a VX2 Liver Tumor: Investigating Efficacy, Safety, and Improvement of Tumor Angiogenesis After Embolization

Objective

To investigate the efficiency and safety of callispheres beads loaded with donafenib (DCBs) for embolization in a VX2 liver tumor, as well as the improvement of tumor angiogenesis following embolization.

Methods

Forty New Zealand white rabbit VX2 liver tumors were treated with four different drugs via the hepatic artery: NS (normal saline), CB (blank callispheres beads), ACB (adriamycin-loaded callispheres beads) and DCB (DCBs). Hematoxylin-eosin staining was performed to assess tumor necrosis, while MRI was employed to detect the changes in tumor size. The safety was evaluated by the liver and kidney function parameters, and the immunofluorescence and immunohistochemical staining were performed to reflect the tumor hypoxia and tumor angiogenesis following embolization.

Results

The DCB group had the smallest tumor growth rate, but the tumor necrosis rate was the highest of the four groups. Compared to the CB and ACB groups, the DCB group did not aggravate the liver damage and had no influence on kidney function. The staining results showed that, although the tumor hypoxia deteriorated after DCBs embolization, the expression of VEGF (vascular endothelial growth factor) reduced, thus inhibiting tumor angiogenesis.

Conclusion

DCB administration via hepatic artery is an effective and safe treatment for a preclinical liver cancer model, with the unique benefit of suppressing tumor angiogenesis following embolization.

Advances in locoregional therapy for hepatocellular carcinoma combined with immunotherapy and targeted therapy

Locoregional therapies (LRTs) of hepatocellular carcinoma (HCC) represented by ablation and TACE has become the main means for the clinical treatment of unresectable HCC. Among these, TACE is used throughout the stage Ib to IIIb of HCC treatment. In recent years, immunotherapy led by immune checkpoint inhibitors has become a hot direction in clinical research. At the same time, targeted drugs such as Sorafenib and Apatinib have played an important role in the treatment and complementary therapy of advanced HCC, and their clinical application has been quite mature. HCC is the sixth most common malignant tumor in the world. When it comes to its treatment, different therapies have different indications, and their individual efficacies are not satisfactory, which makes the exploration of the use of combination therapy in HCC treatment become a new trend. In this paper, the status of the three therapies and the progress of their combined application are briefly reviewed.

Sequential transarterial chemoembolization and early radiofrequency ablation improves clinical outcomes for early-intermediate hepatocellular carcinoma in a 10-year single-center comparative study

Background

Transarterial chemoembolization (TACE) and radiofrequency ablation (RFA) are effective treatment methods for unresectable hepatocellular carcinoma (HCC). However, there is still a lack of clinical research on whether early sequential RFA, compared with late combination therapy, can improve the long-term efficacy of initial TACE treatment.

Methods

This retrospective study investigated a cohort of patients who underwent combination therapy using TACE and RFA (TACE followed by RFA) from January 2010 to January 2020 at our medical centre. A total of 96 patients underwent TACE combined with early RFA (usually during the first hospitalization), which was called TACE + eRFA. Thirty-four patients received 1–2 palliative TACE treatments first and then underwent TACE treatment combined with late RFA (TACE + lRFA). All patients continued to receive palliative TACE treatments after intrahepatic lesion progression until reaching intolerance. The overall survival (OS) rate, time to tumour progression (TTP), tumour response rate and major complication rates were compared between the two groups.

Results

There were significant differences in the median OS (46 months vs 33 months; P = 0.013), median TTP (28 months vs 14 months; P < 0.00), objective response rate (ORR) (89.6% vs 61.8%, P = 0.000) and disease control rate (DCR) (94.8% vs 73.5% P = 0.002) between the two groups. Multivariable analysis revealed that the Barcelona Clinic Liver Cancer stage was an independent risk factor for OS. Meanwhile, multivariable analysis revealed that TACE + eRFA was associated with an enhanced TTP.

Conclusion

Early sequential RFA treatment in patients with early-intermediate HCC can improve local tumour control and clinical outcomes while reducing the frequency of TACE treatment. In clinical practice, in HCC patients initially treated with TACE, it is recommended to combine RFA as soon as possible to obtain long-term survival.

Chinese expert consensus on technical recommendations for the standard operation of drug-eluting beads for transvascular embolization

Liver cancer is among the 10 most common tumors globally. In China, liver cancer ranks 4^th for prevalence and 3^rd for mortality among all malignant tumors. With respect to the treatment of primary liver cancer, there are a number of therapies currently available, including surgical resection, liver transplantation, ablation, transarterial chemoembolization (TACE), systemic chemotherapy, radiation therapy, targeted drug therapy and immunotherapy. Clinical practice and research have shown that, compared with conventional TACE (cTACE), drug-eluting bead TACE (DEB-TACE) can achieve a higher response rate and longer survival time in patients with primary liver cancer. Compared with that of cTACE, DEB-TACE has more favorable basic conditions for achieving uniformity, which could facilitate the standardization of operation techniques. China is the country with the highest incidence of primary liver cancer, accounting for more than 50% of the global patients, and its etiology and epidemiology in Chinese patients differ from those in Europeans and Americans. Therefore, experts in China have drafted these technical recommendations for the standard operation of drug-eluting beads for the treatment of liver cancer on the basis of accumulated abundant clinical experience and evidence-based medical data.

Drug-eluting embolic microspheres: State-of-the-art and emerging clinical applications

INTRODUCTION

Drug-eluting embolic (DEE) microspheres, or drug-eluting beads (DEB), delivered by transarterial chemoembolization (TACE) serve as a therapeutic embolic to stop blood flow to tumors and a drug delivery vehicle. New combinations of drugs and DEE microspheres may exploit the potential synergy between mechanisms of drug activity and local tissue responses generated by TACE to enhance the efficacy of this mainstay therapy.

AREAS COVERED

This review provides an overview of key drug delivery concepts related to DEE microspheres with a focus on recent technological developments and promising emerging clinical applications as well as speculation into the future.

EXPERT OPINION

TACE has been performed for nearly four decades by injecting chemotherapy drugs into the arterial supply of tumors while simultaneously cutting off their blood supply, trying to starve and kill cancer cells, with varying degrees of success. The practice has evolved over the decades but has yet to fulfill the promise of truly personalized therapies envisioned through rational selection of drugs and real-time multi-parametric image guidance to target tumor clonality or heterogeneity. Recent technologic and pharmacologic developments have opened the door for potentially groundbreaking advances in how TACE with DEE microspheres is performed with the goal of achieving advancements that benefit patients.

Towards the use of localised delivery strategies to counteract cancer therapy-induced cardiotoxicities

Cancer therapies have significantly improved cancer survival; however, these therapies can often result in undesired side effects to off target organs. Cardiac disease ranging from mild hypertension to heart failure can occur as a result of cancer therapies. This can warrant the discontinuation of cancer treatment in patients which can be detrimental, especially when the treatment is effective. There is an urgent need to mitigate cardiac disease that occurs as a result of cancer therapy. Delivery strategies such as the use of nanoparticles, hydrogels, and medical devices can be used to localise the treatment to the tumour and prevent off target side effects. This review summarises the advancements in localised delivery of anti-cancer therapies to tumours. It also examines the localised delivery of cardioprotectants to the heart for patients with systemic disease such as leukaemia where localised tumour delivery might not be an option.

Locoregional Therapy Approaches for Hepatocellular Carcinoma: Recent Advances and Management Strategies

Hepatocellular carcinoma (HCC) is the most common primary liver malignancy and third leading cause of cancer-related mortality worldwide. While surgical resection and transplantation are the standard first-line treatments for early-stage HCC, most patients do not fulfill criteria for surgery. Fortunately, catheter-directed and percutaneous locoregional approaches have evolved as major treatment modalities for unresectable HCC. Improved outcomes have been achieved with novel techniques which can be employed for diverse applications ranging from curative-intent for small localized tumors, to downstaging or bridging to resection and transplantation for early and intermediate disease, and locoregional control and palliation for advanced disease. This review explores recent advances in liver-directed techniques for HCC including bland transarterial embolization, chemoembolization, radioembolization, and ablative therapies, with a focus on patient selection, procedural technique, periprocedural management, and outcomes.

Angiogenesis Analyzer for ImageJ - A comparative morphometric analysis of "Endothelial Tube Formation Assay" and "Fibrin Bead Assay"

Angiogenesis assays based on in vitro capillary-like growth of endothelial cells (EC) are widely used, either to evaluate the effect of anti- and pro-angiogenesis drugs of interest, or to test and compare the functional capacities of various types of EC and progenitor cells. Among the different methods applied to study angiogenesis, the most commonly used is the "Endothelial Tube Formation Assay" (ETFA). In suitable culture conditions, EC form two-dimensional (2D) branched structures that can lead to a meshed pseudo-capillary network. An alternative approach to ETFA is the "Fibrin Bead Assay" (FBA), based on the use of Cytodex 3 microspheres, which promote the growth of 3D capillary-like patterns from coated EC, suitable for high throughput in vitro angiogenesis studies. The analytical evaluation of these two widely used assays still remains challenging in terms of observation method and image analysis. We previously developed the "Angiogenesis Analyzer" for ImageJ (AA), a tool allowing analysis of ETFA-derived images, according to characteristics of the pseudo-capillary networks. In this work, we developed and implemented a new algorithm for AA able to recognize microspheres and to analyze the attached capillary-like structures from the FBA model. Such a method is presented for the first time in fully automated mode and using non-destructive image acquisition. We detailed these two algorithms and used the new AA version to compare both methods (i.e. ETFA and FBA) in their efficiency, accuracy and statistical relevance to model angiogenesis patterns of Human Umbilical Vein EC (HUVEC). Although the two methods do not assess the same biological step, our data suggest that they display specific and complementary information on the angiogenesis processes analysis.

Preparation of microspheres encapsulating sorafenib and catalase and their application in rabbit VX2 liver tumor

BACKGROUND

Transcatheter arterial chemoembolization (TACE) is extensively used in the treatment of advanced hepatocellular carcinoma (HCC). However, the efficacy of TACE is usually limited to secondary tumor hypoxia and hypoxia-related tumor angiogenesis.

METHODS

In this study, poly(lactic-co-glycolic acid) (PLGA) microspheres (SOR-CAT-PLGA MSs) encapsulating sorafenib (SOR) and catalase (CAT) were prepared by double-emulsion solvent diffusion method. Sorafenib inhibits tumor angiogenesis, and catalase decomposes hydrogen peroxide (H₂O₂) to generate oxygen in the tumor.

RESULTS

In vitro and in vivo, SOR -CAT-PLGA MSs could significantly improve the efficacy of hepatic artery embolization in the treatment of rabbit VX2 liver tumors, regulate tumor hypoxia and immunosuppressive microenvironment, then achieved near-complete and rapid necrosis of liver tumors.

CONCLUSIONS

The application of new SOR -CAT-PLGA MSs in hepatic artery chemoembolization of rabbit VX2 liver tumor is a promising approach to improve the therapeutic effect of liver tumors and has a broad clinical application prospect.

Revascularization and limb salvage following critical limb ischemia by nanoceria-induced Ref-1/APE1-dependent angiogenesis

In critical limb ischemia (CLI), overproduction of reactive oxygen species (ROS) and impairment of neovascularization contribute to muscle damage and limb loss. Cerium oxide nanoparticles (CNP, or 'nanoceria') possess oxygen-modulating properties which have shown therapeutic utility in various disease models. Here we show that CNP exhibit pro-angiogenic activity in a mouse hindlimb ischemia model, and investigate the molecular mechanism underlying the pro-angiogenic effect. CNP were injected into a ligated region of a femoral artery, and tissue reperfusion and hindlimb salvage were monitored for 3 weeks. Tissue analysis revealed stimulation of pro-angiogenic markers, maturation of blood vessels, and remodeling of muscle tissue following CNP administration. At a dose of 0.6 mg CNP, mice showed reperfusion of blood vessels in the hindlimb and a high rate of limb salvage (71%, n = 7), while all untreated mice (n = 7) suffered foot necrosis or limb loss. In vitro, CNP promoted endothelial cell tubule formation via the Ref-1/APE1 signaling pathway, and the involvement of this pathway in the CNP response was confirmed in vivo using immunocompetent and immunodeficient mice and by siRNA knockdown of APE1. These results demonstrate that CNP provide an effective treatment of CLI with excessive ROS by scavenging ROS to improve endothelial survival and by inducing Ref-1/APE1-dependent angiogenesis to revascularize an ischemic limb.

Locoregional Therapy, Immunotherapy and the Combination in Hepatocellular Carcinoma: Future Directions

Image-guided locoregional therapies (LRTs) have long been a vital part of treatment regimens for hepatocellular carcinoma (HCC). Ablation, chemoembolization, and radioembolization are examples of commonly used treatment techniques for HCC. This review describes the various methods utilized to treat HCC in the field of interventional oncology and also focuses on new and novel treatment concepts being developed in the field including the use of novel immunotherapy agents and combination therapy of LRTs with immunotherapy.

Intermediate stage hepatocellular carcinoma: a summary review

It is well known that intermediate stage hepatocellular carcinoma (HCC) encompasses the widest class of patients with this disease. The main characteristic of this special sub-group of patients is that it is extensively heterogenous. This substantial heterogeneity is due to the wide range of liver functions of such patients and variable tumor numbers and sizes. Real world clinical data show huge support for transarterial chemo-embolization (TACE) as a therapeutic modality for intermediate stage HCC, applied in 50%-60% of those class of patients. There are special considerations in various international guidelines regarding treatment allocation in intermediate stage HCC. There is an epidemiological difference in HCC in eastern and western cohorts, and various guidelines have been proposed. In patients with HCC, it has frequently been reported that there is poor correlation between the clinical benefit and real gain in patient condition and the conventional way of tumor response assessment after locoregional treatments. This is due to the evaluation criteria in addition to the scoring systems used for treatment allocation in those patients. It became clear that intermediate stage HCC patients receiving TACE need a proper prognostic score that offers valid clinical prediction and supports proper decision-making. Also, it is the proper time to study more treatment options beyond TACE, such as multimodal regimens for this class of patients. In this review, we tried to provide a summary of the challenges and future directions in managing patients with intermediate stage HCC.

Current status of the combination therapy of transarterial chemoembolization and local ablation for hepatocellular carcinoma

PURPOSE OF REVIEW

To review the current status and ideal time interval of the combination therapy of transarterial chemoembolization (TACE) and local ablation for patients with HCCs.

RECENT FINDINGS

In recent years, local ablation has been proposed as an alternative curative treatment in the management of HCC. Additionally, many treatment options are available including TACE molecular targeted agents and immune checkpoint inhibitors. Similar overall survival rates and prognoses have been obtained with radiofrequency ablation (RFA) microwave ablation (MWA) and cryoablation for patients with HCCs up to 3 cm in diameter. Yet, MWA has shown superiority in treating large HCCs while cryoablation has several advantages compared with RFA or MWA. Furthermore, the treatment strategy of TACE combined with local ablation is widely accepted by many physicians in order to further increase the survival rate and improve the prognosis of patients with HCCs. However, the time interval between the two sessions of combination therapy remains uncertain in the current guidelines. Combination therapy of TACE and local ablation has advantages on survival and prognosis in patients with HCC compared with monotherapy. Good patient selection for the right modality needs to be carried out to guarantee the most efficacious treatment for HCC patients. Further studies are needed to find the ideal time interval between TACE and local ablation for HCC patients.

AIEgen based poly(L-lactic-co-glycolic acid) magnetic nanoparticles to localize cytokine VEGF for early cancer diagnosis and photothermal therapy

Aim: We demonstrated a novel theranostic system for simultaneous photothermal therapy and magnetic resonance imaging applicable to early diagnostics and treatment of cancer cells. Materials & methods: Oleic acid-Fe3O4 and triphenylamine-divinylanthracene-dicyano were loaded to the poly(L-lactic-co-glycolic acid) nanoparticles (NPs) on which anti-VEGF antibodies were modified to form anti-VEGF/OA-Fe3O4/triphenylamine-divinylanthracene-dicyano@poly(L-lactic-co-glycolic acid) NPs. The 1H nuclear magnetic resonance (NMR), mass spectra, fluorescence, UV absorption, dynamic light scattering, transmission electron microscope and inductively coupled plasma mass spectrometry tests were used to characterize the NPs, and the bioimaging was illustrated by confocal laser scanning microscope (CLSM) and in vivo MRI animal experiment. Results: This system was capable to recognize the overexpressed VEGF-A as low as 68 pg/ml in different cell lines with good selectivity and photothermal therapy effect. Conclusion: These ultrasensitive theranostic NPs were able to identify tumor cells by fluorescence imaging and MRI, and destroy tumors under near infrared illumination.

Aspherical, Nanostructured Microparticles for Targeted Gene Delivery to Alveolar Macrophages

Introducing novel shapes to particulate carrier systems adds unique features to modern drug and gene delivery. Depending on the route of administration, particle geometry can influence deposition and fate within biological environments. In this work, a template-assisted engineering technique is applied, providing full control of size and shape in the preparation of aspherical, nanostructured microparticles. Based on the interconnection of nanoparticles, stabilized by a functional layer-by-layer (LbL) coating, the resulting cylindrical micrometer architecture is especially qualified for pulmonary delivery. Designed as gene delivery system, plasmid-DNA (pCMV-luciferase) and branched polyethylenimine are used to reach both structural integrity of the carrier system and delivery of genes into the cells of interest. Due to their size, particles are exclusively taken up by phagocytes, which also adds a targeting effect to the introduced system. The luciferase expression is demonstrated in macrophages showing increasing levels over a time period of at least 7 d. Furthermore, it is shown for the first time that the expression is depending on the LbL design. From in vivo experiments, corresponding luciferase expression is observed in mice alveolar macrophages. Combining site specific transport with the possibility of genetically engineering immunocompetent phagocytes, the presented system offers promising potential to improve applications for cell-based immunotherapy.

Drug-eluting embolic microspheres for local drug delivery - State of the art

Embolic microspheres or beads used in transarterial chemoembolization are an established treatment method for hepatocellular carcinoma patients. The occlusion of the tumor-feeding vessels by intra-arterial injection of the beads results in tumor necrosis and shrinkage. In this short review, we describe the utility of using these beads as devices for local drug delivery. We review the latest advances in the development of non-biodegradable and biodegradable drug-eluting beads for transarterial chemoembolization. Their capability to load different drugs, such as chemotherapeutics and anti-angiogenic compounds with different physicochemical properties, like charge and hydrophilicity/hydrophobicity, are discussed. We specifically address controlled and sustained drug release from the microspheres, and the resulting in vivo pharmacokinetics in the plasma vs. drug distribution in the targeted tissue.

The impact of antiangiogenic therapy combined with Transarterial Chemoembolization on enhancement based quantitative tumor response assessment in patients with hepatocellular carcinoma

PURPOSE

To investigate whether bevacizumab compromises early response assessment after Transarterial Chemoembolization (TACE) in patients with hepatocellular carcinoma by 3D quantitative European Association for the Study of the Liver (qEASL) criteria in comparison to other imaging-based criteria.

MATERIALS AND METHODS

Each of 14 patients receiving TACE and bevacizumab was matched with two patients receiving TACE alone. Baseline and Follow-up MRI was retrospectively analyzed regarding qEASL and other imaging-based criteria.

RESULTS

Percentage-based qEASL achieved significant separation in both therapy arms (p=0.046 and p=0.015). Response and Overall Survival showed similar association among treatment groups (p=0.749).

CONCLUSIONS

Anti-angiogenic therapy with bevacizumab does not impede early response assessment by qEASL.

Review of the Development of Methods for Characterization of Microspheres for Use in Embolotherapy: Translating Bench to Cathlab

Therapeutic embolotherapy is the deliberate occlusion of a blood vessel within the body, which can be for the prevention of internal bleeding, stemming of flow through an arteriovenous malformation, or occlusion of blood vessels feeding a tumor. This is achieved using a wide selection of embolic devices such as balloons, coils, gels, glues, and particles. Particulate embolization is often favored for blocking smaller vessels, particularly within hypervascularized tumors, as they are available in calibrated sizes and can be delivered distally via microcatheters for precise occlusion with associated locoregional drug delivery. Embolic performance has been traditionally evaluated using animal models, but with increasing interest in the 3R's (replacement, reduction, refinement), manufacturers, regulators, and clinicians have shown interest in the development of more sophisticated in vitro methods for evaluation and prediction of in vivo performance. Herein the current progress in developing bespoke techniques incorporating physical handling, fluid dynamics, occlusive behavior, and sustained drug elution kinetics within vascular systems is reviewed. While it is necessary to continue to validate the safety of such devices in vivo, great strides have been made in the development of bench tests that better predict the behavior of these products aligned with the principles of the 3R's.

Characterization of a novel intrinsically radiopaque Drug-eluting Bead for image-guided therapy: DC Bead LUMI™

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.

Preparation and characterisation of vandetanib-eluting radiopaque beads for locoregional treatment of hepatic malignancies

Since their introduction around a decade ago, embolic drug-eluting beads (DEBs) have become a well-established treatment option for the locoregional transarterial treatment of hepatic malignancies. Despite this success, the therapy is seen to be limited by the choice of drug and more effective options are therefore being sought. These include the small molecule multi-tyrosine kinase inhibitors (MTKi), which exert an anti-angiogenic and anti-proliferative effect that could be highly beneficial in combating some of the unwanted downstream consequences of embolization. Vandetanib is an MTKi which acts against such targets as vascular endothelial growth factor receptor (VEGFR) and epithelial growth factor receptor (EGFR) and has demonstrated modest activity against hepatocellular carcinoma (HCC), albeit with some dose-limiting cardiac toxicity. This makes this compound an interesting candidate for DEB-based locoregional delivery. In this study we describe the preparation and characterisation of vandetanib DEBs made from DC Bead™ and its radiopaque counterpart, DC Bead LUMI™. Drug loading was shown to be dependent upon the pH of the drug loading solution, as vandetanib has multiple sites for protonation, with the bead platform also having a fundamental influence due to differences in binding capacities and bead shrinkage effects. Fourier transform infrared (FTIR) spectroscopy and energy dispersive X-ray (EDX) Spectroscopy confirmed drug interaction is by ionic interaction, and in the case of the radiopaque DEB, the drug is distributed uniformly inside the bead and contributes slightly to the overall radiopacity by virtue of a bromine atom on the vandetanib structure. Drug release from both bead platforms is controlled and sustained, with a slightly slower rate of release from the radiopaque bead due to its more hydrophobic nature. Vandetanib DEBs therefore have suitable characteristics for intra-arterial delivery and site-specific sustained release of drug into liver tumours.