Highly Tumor-Specific and Long-Acting Iodine-131 Microbeads for Enhanced Treatment of Hepatocellular Carcinoma with Low-Dose Radio-Chemoembolization

Ultrastable PLGA-Coated 177Lu-Microspheres for Radioembolization Therapy of Hepatocellular Carcinoma

Transarterial radioembolization (TARE) is a highly effective localized radionuclide therapy that has been successfully used to treat hepatocellular carcinoma (HCC). Extensive research has been conducted on the use of radioactive microspheres (MSs) in TARE, and the development of ideal radioactive MSs is crucial for clinical trials and patient treatment. This study presents the development of a radioactive MS for TARE of HCC. These MSs, referred to as 177Lu-MS@PLGA, consist of poly(lactic-co-glycolic acid) (PLGA) copolymer and radioactive silica MSs, labeled with 177Lu and then coated with PLGA. It has an extremely high level of radiostability. Cellular experiments have shown that it can cause DNA double-strand breaks, leading to cell death. In vivo radiostability of 177Lu-MS@PLGA is demonstrated by microSPECT/CT imaging. In addition, the antitumor study has shown that TARE of 177Lu-MS@PLGA can effectively restrain tumor growth without harmful side effects. Thus, 177Lu-MS@PLGA exhibits significant potential as a radioactive MS for the treatment of HCC.

EUS-guided interventional therapies for pancreatic diseases

Endoscopic ultrasound (EUS) is an integrated diagnostic technique merging endoscope and ultrasound to examine the digestive system. EUS has emerged as a primary diagnostic method for pancreatic diseases due to its distinctive benefits. Over the past four decades, EUS has undergone a transformation, shifting its role from primarily diagnostic to increasingly therapeutic. Additionally, in recent years, EUS has emerged as an increasingly prominent adjunctive or alternative approach to conventional surgical interventions. This review provides a comprehensive analysis of current technological approaches in the treatment of pancreatic diseases. The dynamic interplay with diverse therapeutic approaches has reinvigorated EUS and shaped its trajectory in the management of pancreatic diseases.

Self-fueling ferroptosis-inducing microreactors based on pH-responsive Lipiodol Pickering emulsions enable transarterial ferro-embolization therapy

Lipiodol chemotherapeutic emulsions remain one of the main choices for the treatment of unresectable hepatocellular carcinoma (HCC) via transarterial chemoembolization (TACE). However, the limited stability of Lipiodol chemotherapeutic emulsions would lead to rapid drug diffusion, which would reduce the therapeutic benefit and cause systemic toxicity of administrated chemotherapeutics. Therefore, the development of enhanced Lipiodol-based formulations is of great significance to enable effective and safe TACE treatment. Herein, a stable water-in-oil Lipiodol Pickering emulsion (LPE) stabilized by pH-dissociable calcium carbonate nanoparticles and hemin is prepared and utilized for efficient encapsulation of lipoxygenase (LOX). The obtained LOX-loaded CaCO3&hemin-stabilized LPE (LHCa-LPE) showing greatly improved emulsion stability could work as a pH-responsive and self-fueling microreactor to convert polyunsaturated fatty acids (PUFAs), a main component of Lipiodol, to cytotoxic lipid radicals through the cascading catalytic reaction driven by LOX and hemin, thus inducing ferroptosis of cancer cells. As a result, such LHCa-LPE upon transcatheter embolization can effectively suppress the progression of orthotopic N1S1 HCC in rats. This study highlights a concise strategy to prepare pH-responsive and stable LPE-based self-fueling microreactors, which could serve as bifunctional embolic and ferroptosis-inducing agents to enable proof-of-concept transarterial ferro-embolization therapy of HCC.

Radioiodine-131-Labeled Theranostic Nanoparticles for Transarterial Radioembolization and Chemoembolization Combination Therapy of VX2 Liver Tumor

In interventional treatment, materials are administered into the blood supply artery and directly delivered to tumors, offering proper scenarios for nanomedicine potential clinical applications. Transarterial chemoembolization (TACE) and transarterial radioembolization (TARE) are effective treatment methods for hepatocellular carcinoma (HCC), but postoperative residual tumor may result in intrahepatic recurrence and distant metastasis. The combination therapy of TACE and TARE based on multifunctional nanoparticles (NPs) is expected to overcome the drug resistance in hypoxic tumors and improve the therapeutic effect. Herein, BaGdF5 NPs are synthesized and then coated with polydopamine (PDA), conjugated with the chemotherapeutic drug cis-diamminedichloride platinum (CDDP), radio-labeled with therapeutic radionuclide 131 I, yielding 131 I-BaGdF5 @PDA-CDDP NPs. The in vitro anti-cancer effects of 131 I-BaGdF5 @PDA-CDDP NPs are confirmed using CCK-8 and γ-H2AX assays in Huh7 cells. Mixed with Lipiodol, 131 I-BaGdF5 @PDA-CDDP NPs are injected into the hepatic artery via a microcatheter to realize the TACE and TARE combination therapy in a rabbit VX2 liver tumor model. The results indicate that glucose metabolism is clearly decreased based on 18 F-FDG PET imaging and the apoptosis of tumor cells is increased. Furthermore, 131 I and BaGdF5 NPs can be used for SPECT imaging and CT/MR imaging respectively, facilitating real-time monitoring of the in vivo biodistribution of 131 I-BaGdF5 @PDA-CDDP NPs.

Macrocyclic-Albumin Conjugates for Precise Delivery of Radionuclides and Anticancer Drugs to Tumors

Precise delivery of radionuclides and anticancer drugs to tumor tissue is crucial to ensuring drug synergism and optimal therapeutic effects in radionuclide-based combination radio-chemotherapy. However, current codelivery vectors often rely on physical embedment/adsorption to load anticancer drugs, which lacks precise mechanisms for drug loading and release, resulting in unpredictable combination effects. Herein, a macrocyclic-albumin conjugate (MAC) that enables precise loading and controlled release of anticancer drugs is presented. By conjugating multiple macrocyclic hosts (sulfonate azocalix[4]arenes, SAC4A) to albumin molecules, the MAC facilitates the precise loading of anticancer drugs through host-guest interactions and site-specific labeling of radionuclides. Furthermore, the MAC degrades under hypoxic conditions, enabling the release of loaded drugs upon reaching tumor tissues. Through precise loading and targeted delivery of radionuclides and anticancer drugs, MAC achieves efficient cancer diagnosis and combined radio-chemotherapy in breast cancer cell (4T1)-bearing mice. Considering that SAC4A can load many anticancer drugs, MAC may provide a promising platform for effective combination radio-chemotherapy.

Microfluidic Controllable Preparation of Iodine-131-Labeled Microspheres for Radioembolization Therapy of Liver Tumors

Transcatheter arterial radioembolization (TARE) is of great significance for the treatment of advanced hepatocellular carcinoma (HCC). However, the existing radioembolic microspheres still have problems such as non-degradability, non-uniform size, and inability to directly monitor in vivo, which hinders the development of TARE. In this paper, a novel radioembolic agent, 131 I-labeled methacrylated gelatin microspheres (131 I-GMs), is prepared for the treatment of HCC. Water-in-oil (W/O) emulsion templates are prepared by a simple one-step microfluidic method to obtain methacrylated gelatin microspheres (GMs) after UV irradiation. A series of GMs with uniform and controllable size is obtained by adjusting the flow rate of each fluid. Both air-dried and freeze-dried GMs can quickly restore their original shape and size, and still have good monodispersity, elasticity, and biocompatibility. The radiolabeling experiments show that 131 I can efficiently bind to GMs by chloramine-T method, and the obtained 131 I-GMs have good radioactive stability in vitro. The results of in vivo TARE treatment in rats show that 131 I-GMs can be well retained in the hepatic artery and have a good inhibitory effect on the progression of liver cancer, showing the potential for the treatment of HCC.

Local Sustained Chemotherapy of Pancreatic Cancer Using Endoscopic Ultrasound-Guided Injection of Biodegradable Thermo-Sensitive Hydrogel

Purpose

Endoscopic ultrasound-guided fine-needle injection (EUS-FNI) offers a promising minimally invasive approach for locally targeted management of advanced pancreatic cancer. However, the efficacy is limited due to the rapid plasma clearance of chemotherapeutic agents. Injectable hydrogels can form drug release depots, which provide a feasible solution for optimizing targeted chemotherapy through EUS-FNI.

Methods

A drug delivery system was developed, consisting of gemcitabine (GEM) and thermo-sensitive hydrogel (PLGA-PEG-PLGA, PPP). The injectability, gel formation ability, biocompatibility and sustained drug delivery properties of PPP hydrogel were verified in vitro and in vivo. The effects of GEM/PPP hydrogel on cell proliferation, invasion, metastasis, and apoptosis were explored through co-culturing with PANC-1 cells. The therapeutic effects of GEM/PPP hydrogel on xenograft mice were compared with those of GEM, ethanol and polidocanol using the precisely targeted EUS-FNI technology. Tumor sections were examined by H&E, Ki-67, and TUNEL staining.

Results

GEM/PPP hydrogel exhibited excellent injectability, biocompatibility, and the capability of sustained drug delivery for up to 7 days by forming a gel triggered by body temperature. It demonstrated the best therapeutic effects, significantly reducing proliferation, invasion and migration of PANC-1 cells while promoting apoptosis. After precise injection using EUS-FNI technology, GEM/PPP hydrogel resulted in a reduction of tumor weight by up to 75.96% and extending the survival period by 14.4 days with negligible adverse effects. Pathological examination revealed no systemic toxicity and significant apoptosis and minimal proliferation as well.

Conclusion

The combination of GEM/PPP hydrogel and EUS-FNI technology provides an optimal approach of precise chemotherapy for pancreatic cancer, builds a bridge for clinical translation of basic research, and brings great hope for innovation of minimally invasive treatment modalities. The first-hand EUS image data obtained in this study also serves as a crucial reference for future clinical trials.

Polydopamine-Coated Radiolabeled Microspheres for Combinatorial Radioembolization and Photothermal Cancer Therapy

Transarterial radioembolization (TARE) is a local radionuclide therapy and is successfully used in hepatocellular carcinoma (HCC) treatment. Radioactive microspheres have been widely studied for TARE. Preparation of ideal radioactive microspheres is significant for clinical research and patient treatment. In this study, we have designed a novel multifunctional microsphere, i.e., polydopamine (PDA)-coated ¹⁷⁷Lu-radiolabeled silica microspheres (MS) denoted as ¹⁷⁷Lu-MS@PDA, which can be used for TARE and photothermal therapy (PTT). The radiostability of ¹⁷⁷Lu-MS@PDA was significantly improved by coating ¹⁷⁷Lu-MS with PDA. In addition, the coating of PDA makes microspheres have excellent photothermal performance. MicroSPECT/CT images showed that ¹⁷⁷Lu-MS@PDA was accurately embolized and remained in the tumor during the observation time. At the time, it also showed that ¹⁷⁷Lu-MS@PDA was very stable in vivo. Furthermore, the anti-tumor results demonstrated that TARE combined with PTT of ¹⁷⁷Lu-MS@PDA can significantly inhibit tumor growth without obvious side effects. ¹⁷⁷Lu-MS@PDA holds great potential as a promising radioactive microsphere for HCC.

Radionuclide Labeled Nanocarrier for Imaging Guided Combined Radionuclide, Sonodynamic, and Photothermal Therapy of Pancreatic Tumours

Radionuclide therapy (RNT) is an effective method for the clinical precise treatment of cancer. However, the uneven dose distribution and rapid metabolism of nuclides limit the effective killing of tumors. To overcome the limitations of radionuclide therapeutic approaches, combining different therapeutic strategies to treat cancer has manifested great promise in basic and clinical research. Here, a new combination therapy strategy was developed to combine radionuclide therapy, sonodynamic therapy and photothermal therapy (RNT-SDT-PTT) under radionuclide imaging guided achieve highly effective combination therapy. We prepared a polydopamine-modified Au nanostar (AN), then loaded with the acoustic sensitizer protoporphyrin (IX) and labeled with diagnostic (^99mTc) or therapeutic (¹³¹I) radionuclides (¹³¹I/^99mTc-AN@D/IX) for the precise diagnosis and treatment of pancreatic cancer. After intratumor administration, single photon emission computed tomography imaging showed that the nanocarriers were mostly retained in the tumor compared to free radionuclide. As well as using near-infrared light to trigger PTT and ultrasound with high penetration depth to activate IX to generate reactive oxygen species achieved SDT of tumor. The ultimate significantly improved the inhibitory effects by the RNT-SDT-PTT combined therapy for pancreatic cancer. Therefore, this study proposes an effective radionuclide combination therapy regimen consisting of three widely used treatments, offering promising prospects for the future of oncology.

Smart nanoparticles and microbeads for interventional embolization therapy of liver cancer: state of the art

The process of transcatheter arterial chemoembolization is characterized by the ability to accurately deliver chemotherapy drugs with minimal systemic side effects and has become the standard treatment for unresectable intermediate hepatocellular carcinoma (HCC). However, this treatment option still has much room for improvement, one of which may be the introduction of nanomaterials, which exhibit unique functions and can be applied to in vivo tumor imaging and therapy. Several biodegradable and multifunctional nanomaterials and nanobeads have recently been developed and applied in the locoregional treatment of hepatocellular cancer. This review explores recent developments and findings in relation to micro-nano medicines in transarterial therapy for HCC, emerging strategies to improve the efficacy of delivering nano-based medicines, and expounding prospects for clinical applications of nanomaterials.

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.

Embolization therapy with microspheres for the treatment of liver cancer: State-of-the-art of clinical translation

Embolization with microspheres is a therapeutic strategy based on the selective occlusion of the blood vessels feeding a tumor. This procedure is intraarterially performed in the clinical setting for the treatment of liver cancer. The practice has evolved over the last decade through the incorporation of drug loading ability, biodegradability and imageability with the subsequent added functionality for the physicians and improved clinical outcomes for the patients. This review highlights the evolution of the embolization systems developed through the analysis of the marketed embolic microspheres for the treatment of malignant hepatocellular carcinoma, namely the most predominant form of liver cancer. Embolic microspheres for the distinct modalities of embolization (i.e., bland embolization, chemoembolization and radioembolization) are here comprehensively compiled with emphasis on material characteristics and their impact on microsphere performance. Moreover, the future application of the embolics under clinical investigation is discussed along with the scientific and regulatory challenges ahead in the field. STATEMENT OF SIGNIFICANCE: Embolization therapy with microspheres is currently used in the clinical setting for the treatment of most liver cancer conditions. The progressive development of added functionalities on embolic microspheres (such as biodegradability, imageability or drug and radiopharmaceutical loading capability) provides further benefit to patients and widens the therapeutic armamentarium for physicians towards truly personalized therapies. Therefore, it is important to analyze the possibilities that advanced biomaterials offer in the field from a clinical translational perspective to outline the future trends in therapeutic embolization.

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.

Anchoring Group-Mediated Radiolabeling of Inorganic Nanoparticles─A Universal Method for Constructing Nuclear Medicine Imaging Nanoprobes

Nuclear medicine imaging has aroused great interest in the design and synthesis of versatile radioactive nanoprobes, while most of the methods developed for radiolabeling nanoprobes are difficult to satisfy the criteria of clinical translation, including easy operation, mild labeling conditions, high efficiency, and high radiolabeling stability. Herein, we demonstrated the universality of a simple but efficient radiolabeling method recently developed for constructing nuclear imaging nanoprobes, that is, ligand anchoring group-mediated radiolabeling (LAGMERAL). In this method, a diphosphonate-polyethylene glycol (DP-PEG) decorating on the surface of inorganic nanoparticles plays an essential role. In principle, owing to the strong binding affinity to a great variety of metal ions, it can not only endow the underlying nanoparticles containing metal ions including some main group metal ions, transition metal ions, and lanthanide metal ions with excellent colloidal stability and biocompatibility but also enable efficient radiolabeling through the diphosphonate group. Based on this assumption, inorganic nanoparticles such as Fe₃O₄ nanoparticles, NaGdF₄:Yb,Tm nanoparticles, and Cu_2-xS nanoparticles, as representatives of functional inorganic nanoparticles suitable for different imaging modalities including magnetic resonance imaging (MRI), upconversion luminescence imaging (UCL), and photoacoustic imaging (PAI), respectively, were chosen to be radiolabeled with different kinds of radionuclides such as SPECT nuclides (e.g., ^99mTc), PET nuclides (e.g., ⁶⁸Ga), and therapeutic SPECT nuclides (e.g., ¹⁷⁷Lu) to demonstrate the reliability of the LAGMERAL approach. The experimental results showed that the obtained nanoprobes exhibited high radiolabeling stability, and the whole radiolabeling process had negligible impacts on the physical and chemical properties of the initial nanoparticles. Through passive targeting SPECT/MRI of glioma tumor, active targeting SPECT/UCL of colorectal cancer, and SPECT/PAI of lymphatic metastasis, the outstanding potentials of the resulting radioactive nanoprobes for sensitive tumor diagnosis were demonstrated, manifesting the feasibility and efficiency of LAGMERAL.

Recent advances in hepatocellular carcinoma therapeutic strategies and imaging-guided treatment

Hepatocellular carcinoma (HCC) is one of the most common malignant cancer in the world, which greatly threatens human health. However, the routine treatment strategies for HCC have failed to specifically eradicate the tumorigenic cells, leading to the occurrence of metastasis and recurrence. To improve treatment efficacies, the development of novel effective technologies is urgently required. Recently, nanotechnologies have gained the extensive attention in cancer targeted therapy, which could provide a promising way for HCC clinical practice. However, a successful cancer management depends on accurate diagnosis of the tumour along with precise therapeutic protocol, thereby predicting the tumour response to existing therapies. The synergistic effect of targeted therapeutic systems and imaging approaches (also called 'imaging-guided cancer treatment') may establish a more effective platform for individual cancer care. This review outlines the recent advanced nano-targeted and -traceable therapeutic strategies for HCC management. The multifunctional nano agents that have both diagnosis and therapy abilities are highlighted. Finally, we conclude with our perspectives on the future development and challenges of HCC nanotheranostics.

MiR-513b-5p represses autophagy during the malignant progression of hepatocellular carcinoma by targeting PIK3R3

Hepatocellular carcinoma (HCC) serves as a prevailing global malignancy with severe mortality and extremely unsatisfactory prognosis, in which autophagy is a fundamental process in liver cancer pathogenesis, but the mechanisms are poorly understood. MicroRNAs (miRNAs) serve as a type of well-recognized non-coding regulators and contribute to the modulation of liver cancer development, from the aspects of diagnosis, progression, and therapy. Here, we aimed to investigate the function of hsa_microRNA-513b-5p (miR-513b-5p) in regulating autophagy during HCC progression. Specifically, our data showed that miR-513b-5p mimic reduced the LC3-II and beclin1 expression but enhanced p62 expression in HCC cells. MiR-513b-5p repressed liver cancer cell proliferation, migration/invasion, and induced apoptosis in vitro. Crucially, miR-513b-5p attenuated tumor growth of liver cancer cells in vivo. In the mechanical investigation, we identified that PIK3R3 mRNA 3′UTR was targeted by miR-513b-5p and miR-513b-5p suppressed PIK3R3 expression. PIK3R3 overexpression partly reversed miR-513b-5p-mediated autophagy, proliferation, and apoptosis of liver cancer cells. Consequently, we concluded that miR-513b-5p repressed autophagy during the malignant progression of HCC by targeting PIK3R3. MiR-513b-5p may be applied as a therapeutic target for HCC.