Superabsorbent Polymer Microspheres Prepared with Hypertonic Saline to Reduce Microsphere Expansion

Effects of HepaSphere microsphere encapsule epirubicin with a new loading method transarterial chemoembolization: in vitro and in vivo experiments

METHODS

HS microspheres were loaded in a solution of hypertonic saline and contrast medium at different ratios. Morphology, size distribution, and drug loading capacity of the microsphere were evaluated. Rabbits with hepatic VX2 tumors underwent conventional TACE, drug-eluting beads TACE with HS microsphere loading epirubicin by recommended method (dTACE) or a new loading method (ndTACE). The plasma and tissue epirubicin concentration, tumor necrosis, and the microsphere distribution within the tumor were assessed.

RESULTS

It was found that the mean diameter of HS microspheres was effectively reduced to 102 ± 14 μm after loading with 10.0% NaCl and Ultravist (370 mg I /mL) at a ratio of 2: 8 ml. The loading capacity reached 78.7%. It was noted that the concentration of tumor epirubicin was significantly higher (p = 0.016) in the ndTACE group (11,989.8 ± 5776.6 ng/g) than the concentration in the dTACE (6516.5 ± 3682.3 ng/g) and in cTACE groups (1564.1 ± 696.1 ng/g, p < 0.001). Further, the tumor necrosis in group with the new loading method (ndTACE) was 92.4%.

CONCLUSIONS

The size of HS microsphere can be effectively reduced when it is loaded with a mixture of hypertonic saline and non-ionic contrast material. HS microsphere loaded with epirubicin using the new method (ndTACE) can increase the drug concentration in tumor and hence exert better improved antitumor effect.

Drug-eluting beads bronchial arterial chemoembolization vs. conventional bronchial arterial chemoembolization in the treatment of advanced non-small cell lung cancer

Purpose

To compare the effectiveness and safety of drug-eluting bead bronchial artery chemoembolization (DEB-BACE) with conventional bronchial artery chemoembolization (cBACE) and provide a novel treatment option for advanced non-small cell lung cancer (NSCLC).

Methods

Patients with advanced NSCLC underwent DEB-BACE or cBACE and were screened retrospectively. Progression-free survival (PFS) and overall survival (OS) were the primary outcome indicators, while technical success rate, objective response rate (ORR), disease control rate (DCR), and adverse events (AEs) were the secondary ones.

Results

A total of 41 patients were enrolled in the study, 12 in the DEB-BACE group and 29 in the cBACE group, according to the treatment regimen. No patient achieved complete response. Eighteen patients achieved partial response (9 in each group), 15 patients achieved stable disease (3 in the DEB-BACE group and 12 in the cBACE group), and eight patients achieved progressive disease (all in the cBACE group) when treated for 2 months. The overall ORR and DCR were 43.9% (18/41) and 80.5% (33/41), respectively. ORR and DCR in the DEB-BACE group were 50.0% (9/12) and 100.0% (12/12), respectively, while ORR and DCR in the cBACE group were 31.0% (9/29) and 72.4% (21/29), respectively. Compared to cBACE, the ORR and DCR of DEB-BACE were significantly improved (p < 0.05). The median PFS was better in the DEB-BACE group than in the cBACE group (6.95 months vs. 3.20 months, respectively, Hazard Ratio [HR] = 0.416; p = 0.005). Furthermore, the median OS was significantly better in the DEB-BACE group than in the cBACE group (28.5 months vs. 22.5 months, respectively, HR = 0.316; p = 0.020).

Conclusion

DEB-BACE has a good safety and therapeutic profile in advanced NSCLC and is superior to cBACE. DEB-BACE can be used as an alternative treatment option for advanced NSCLC, even in elderly patients.

Retrospective Study of the Efficacy and Safety of Chemoembolization with Drug-Eluting Microspheres Combined with Intra-Arterial Infusion of Bevacizumab for Unresectable Hepatocellular Carcinoma

Purpose

To evaluate the efficacy and safety of chemoembolization with drug-eluting microspheres (DEM-TACE) combined with intra-arterial infusion of bevacizumab in patients with unresectable hepatocellular carcinoma (uHCC) and to identify possible prognostic factors.

Patients and Methods

Between November 2014 and December 2020, 34 patients underwent DEM-TACE combined with intra-arterial infusion of bevacizumab for Barcelona Clinic Liver Cancer (BCLC) stage B hepatocellular carcinoma (HCC) beyond the Up-to-seven criteria or BCLC stage C HCC. Patients with extrahepatic metastasis or inferior vena cava invasion were excluded. The primary endpoint was overall survival (OS). The secondary endpoints were safety (assessed using Common Terminology Criteria for Adverse Events v5.0), the response rate at 1 month, and the identification of prognostic factors. The median OS was calculated using the Kaplan-Meier method. The response rate was evaluated according to the modified Response Evaluation Criteria in Solid Tumors. Prognostic factors were investigated by univariate and multivariable analysis using the Cox proportional hazards model.

Results

The median OS was 13 months. BCLC stage and presence of portal vein invasion were not significantly associated with OS. There were no grade ≥3 adverse events. The Child-Pugh class did not decline after treatment in 31 of 34 patients. The overall response rate was 14.2% and the disease control rate was 100%. Significant prognostic factors were alcoholic liver disease, Child-Pugh score of ≥8, and microsphere size of 50-100 μm.

Conclusion

DEM-TACE combined with intra-arterial infusion of bevacizumab is safe and effective, and it could be a treatment option for unresectable HCCs.

Pi-inducedin-situaggregation of sevelamer nanoparticles for vascular embolization

Decades have witnessed rapid progress of polymeric materials for vascular embolic or chemoembolic applications. Commercially available polymeric embolics range from gelatin foam to synthetic polymers such as poly(vinyl alcohol). Current systems under investigation include tunable, bioresorbable microspheres composed of chitosan or poly(ethylene glycol) derivatives,in situgelling liquid embolics with improved safety profiles, and radiopaque embolics that are trackablein vivo. In this paper, we proposed a concept of 'responsive embolization'. Sevelamer, clinically proved as an inorganic phosphate binder, was ground into nanoparticles. Sevelamer nanoparticle is highly mobile and capable of swelling and aggregating in the presence of endogenous inorganic phosphate, thereby effectively occluding blood flow in the vessel as it was administered as an embolic agent for interventional therapy. Moreover, citrated sevelamer nanoparticles delayed the aggregation, preferable to penetrate deeply into the capillary system. On the rabbit VX2 liver cancer model, both sevelamer particles aggregates occlude the tumor feeding artery, but backflow was found for the pristine one, thereby citrate passivation of sevelamer nanoparticles endows it have potential from 'bench to bedside' as a new type of vascular embolic.

Recent advances and applications of microspheres and nanoparticles in transarterial chemoembolization for hepatocellular carcinoma

Transarterial chemoembolization (TACE) is a recommended treatment for patients suffering from intermediate and advanced hepatocellular carcinoma (HCC). As compared to the conventional TACE, drug-eluting bead TACE demonstrates several advantages in terms of survival, treatment response, and adverse effects. The selection of embolic agents is critical to the success of TACE. Many studies have been performed on the modification of the structure, size, homogeneity, biocompatibility, and biodegradability of embolic agents. Continuing efforts are focused on efficient loading of versatile chemotherapeutics, controlled sizes for sufficient occlusion, real-time detection intra- and post-procedure, and multimodality imaging-guided precise treatment. Here, we summarize recent advances and applications of microspheres and nanoparticles in TACE for HCC. This article is categorized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease.

Efficacy of a Glass Membrane Emulsification Device to Form Mixture of Cisplatin Powder with Lipiodol on Transarterial Therapy for Hepatocellular Carcinoma

PURPOSE

To examine physiochemical characteristics and drug release properties of cisplatin powder and lipiodol mixtures formed by a glass membrane emulsification device compared with a 3-way stopcock.

MATERIALS AND METHODS

Seven different types of mixtures were evaluated: cisplatin powder and lipiodol directly mixed (suspension), complete cisplatin solution and lipiodol mixed by a 3-way stopcock or the device (emulsion), incomplete cisplatin solution and lipiodol mixed by a 3-way stopcock or the device (solid-in-water emulsion), and contrast material and cisplatin suspension mixed by a 3-way stopcock or the device (solid-in-oil emulsion).

RESULT

The percentages of water-in-oil were 98.08 ± 0.27% in the emulsion formed by the device, while 70.3 ± 4.63% in the emulsion formed by a 3-way stopcock (P = 0.037). Solid-in-water and solid-in-oil emulsions formed by the device showed 98.09 ± 0.38% and 98.70 ± 0.40% of water-in-oil, respectively, whereas both solid-in-water and solid-in-oil emulsions formed by a 3-way stopcock showed 0.00%. Homogenous droplet sizes were shown by using the device. The half release times of cisplatin in the emulsions formed by the device were 197 ± 19, 244 ± 24 and 478 ± 52 min, respectively, which were significantly longer than the emulsion formed by a 3-way stopcock of 8 ± 8 min (P = 0.046-0.050). Suspension showed the longest release time; however, the viscosity was lowest.

CONCLUSION

The glass membrane emulsification device formed almost 100% water-in-oil, whereas 3-way stopcock produced 100% oil-in-water when incomplete solution or suspension was mixed. Slower cisplatin release was shown in the emulsions formed by the device.

Effect of superabsorbent polymers (SAP) and metal organic frameworks (MOF) wiping sandwich patch on human skin decontamination and detoxification in vitro

Most chemical warfare agents partition rapidly into stratum corneum (SC) and subsequently slowly diffuse through - or are retained in the membrane. Since chemicals can interact with SC components during the process, skin decontamination poses a challenging yet important problem. To address these issues, we have developed a new method in combination with wet and dry decon technologies with new materials for emergency or delayed contamination scenarios. An in vitro human skin diffusion system was employed to model various dermal exposures of radiolabeled chemical warfare simulants, followed by surface decontamination with metal organic frameworks (MOFs), super-absorbent polymers (SAP), and/or dermal decontamination gel (DDGel). All samples measured for radioactive recovery and acetylcholinesterase activity to ascertain relative decon efficacy. Results demonstrated powerful water absorption of SAP, strong catalysis of UiO-66 MOF, and decon enhancement of pre-wetting surface contaminants. SAP had no interfering interactions with MOF yet provided additional benefits as porosity and reactivity that allowed for fast liquidized chemical transportation, absorption, and degeneration. We then designed a cotton-based SAP/MOF patch that worked cooperatively in decontamination and detoxification. Together with pre-wet, SAP/MOF wipe, and DDGel applications, maximum effect was observed in early and/or extended dermal exposure, and no "wash-in" effect occurred.

Transarterial chemoembolization for pulmonary or mediastinal metastases from hepatocellular carcinoma

OBJECTIVE

To evaluate the feasibility, efficacy and safety of transcatheter arterial chemoembolization (TACE) with HepaSphere for patients with pulmonary or mediastinal metastases from hepatocellular carcinoma (HCC).

METHODS

Between June 2009 and January 2018, 14 patients with pulmonary or mediastinal metastases from HCC were treated with TACE with a combination of 1-3 chemotherapeutic drugs followed by HepaSphere embolization. As first end point, local tumor response and adverse events were evaluated after the first session of TACE, with Response Evaluation Criteria In Solid Tumors v. 1.1 and Common Terminology Criteria for Adverse Events v. 4 criteria, respectively. Overall survival was evaluated as secondary end point. TACE was repeated on-demand.

RESULTS

TACE with HepaSphere was well tolerated with acceptable safety profile and no 30 day mortality. 1 month objective response and disease control rate were calculated to be 7.1 and 100%, respectively. Mean tumor size reduction rate was 15.6±9.5% at the first month. Two Grade 3 cytopenia events were seen (14.3 %), however none of the Grade 2 or more post-embolization syndrome was observed. The median overall survival time was 15.0 months and the 1 year, 3 year and 5 year survival rate were, 57.1%, 28.6%, 19.1%, respectively.

CONCLUSION

Early experience showed that the transarterial treatment with HepaSphere is safe and effective treatment for patients with pulmonary or mediastinal metastases from HCC.

ADVANCES IN KNOWLEDGE

Currently, the effects of molecular targeted drugs on HCC metastases are limited and side-effects are relatively frequent. In the present study, transarterial treatment might be a promising treatment for HCC metastasis.

Long-term Histopathologic Follow-up of a Spherical Embolic Agent; Observation of the Transvascular Migration of HepaSphereTM

Very few studies have been published on the long-term histopathologic follow-up of spherical embolic agents after their injection. To our knowledge, there are no reports in the literature regarding pathological analysis of the transvascular migration of HepaSphere particles. We here report a case of a patient with hepatocellular carcinoma (HCC) who underwent liver transplantation 12 months after drug eluting microsphere transcatheter arterial chemoembolization (DEM-TACE), and long-term histopathologic follow-up of the microspheres was performed. Furthermore, to our knowledge, this is the first report in which transvascular migration of a HepaSphere particle was confirmed histologically. A 60-year-old male with chronic hepatitis B was treated with entecavir and seroconversion was obtained. The patient had decompensated cirrhosis, and desired to undergo living donor liver transplantation (LDLT). However, 2 HCC tumors of 3  cm or less were detected in his liver. The transplantation surgeon proposed DEM-TACE as a bridge therapy. The HCCs were located in the right lobe and lateral segment of the liver. A 1.9  F preshaped microcatheter (ProgreatΣ, Terumo, Japan) was selectively inserted into the A3 and anterior segmental branch, 10  mg of epirubicin was injected into each artery, and the arteries were embolized with 7  mg and 13  mg of HepaSphere loaded with epirubicin, respectively. Two months later, contrast-enhanced CT displayed a complete response. At that time, lung metastasis was suspected, but after partial lung resection, the patient was diagnosed as having inflammatory granuloma. One year after DEM-TACE treatment, LDLT was performed. No cancerous cells were detected in the area where the tumor was present, but 22 HepaSphere particles were detected. All particles were present in the interstitium. Furthermore, the transvascular migration of a HepaSphere particle was histologically confirmed. The largest and smallest HepaSphere diameters were 241.6  ±  52.5  µm and 186.5  ±  41.4  µm, respectively, and deformity was 22.6% ± 13.0 %. All the HepaSpheres detected in the examined pathological specimen were noted to be extravascular.