Albumin-Stabilized Metal-Organic Nanoparticles for Effective Delivery of Metal Complex Anticancer Drugs

Metal-organic frameworks in drug delivery: engineering versatile platforms for therapeutic applications

Recently, metal-organic frameworks (MOFs) have attracted much attention as versatile materials for drug delivery and personalized medicine. MOFs are porous structures made up of metal ions coupled with organic ligands. This review highlights the synthesis techniques used to design MOFs with specific features such as surface area and pore size, and the drug encapsulation within MOFs not only improves their stability and solubility but also allows for controlled release kinetics, which improves therapeutic efficacy and minimizes adverse effects. Furthermore, it discusses the challenges and potential advantages of MOF-based drug delivery, such as MOF stability, biocompatibility, and scale-up production. With further advancements in MOF synthesis, functionalization techniques, and understanding of their interactions using biological systems, MOFs can have significant promise for expanding the area of personalized medicine and improving patient outcomes.

Biomimetic gold nanocages incorporating copper-human serum albumin for tumor immunotherapy via cuproptosis-lactate regulation

Cancer immunotherapy remains a significant challenge due to insufficient proliferation of immune cells and the sturdy immunosuppressive tumor microenvironment. Herein, we proposed the hypothesis of cuproptosis-lactate regulation to provoke cuproptosis and enhance anti-tumor immunity. For this purpose, copper-human serum albumin nanocomplex loaded gold nanocages with bacterial membrane coating (BAu-CuNCs) were developed. The targeted delivery and disassembly of BAu-CuNCs in tumor cells initiated a cascade of reactions. Under near infrared (NIR) laser irradiation, the release of copper-human serum albumin (Cu-HSA) was enhanced that reacted with intratumoral glutathione (GSH) via a disulfide exchange reaction to liberate Cu2+ ions and exert cuproptosis. Subsequently, the cuproptosis effect triggered immunogenic cell death (ICD) in tumor by the release of damage associated molecular patterns (DAMPs) to realize anti-tumor immunity via robust production of cytotoxic T cells (CD8+) and helper T cells (CD4+). Meanwhile, under NIR irradiation, gold nanocages (AuNCs) promoted excessive reactive oxygen species (ROS) generation that played a primary role in inhibiting glycolysis, reducing the lactate and ATP level. The combine action of lower lactate level, ATP reduction and GSH depletion further sensitized the tumor cells to cuproptosis. Also, the lower lactate production led to the significant blockage of immunosuppressive T regulatory cells (Tregs) and boosted the anti-tumor immunity. Additionally, the effective inhibition of breast cancer metastasis to the lungs enhanced the anti-tumor therapeutic impact of BAu-CuNCs + NIR treatment. Hence, BAu-CuNCs + NIR concurrently induced cuproptosis, ICD and hindered lactate production, leading to the inhibition of tumor growth, remodeling of the immunosuppressive tumor microenvironment and suppression of lung metastasis. Therefore, leveraging cuproptosis-lactate regulation, this approach presents a novel strategy for enhanced tumor immunotherapy.

Spiderweb-Shaped Iron-Coordinated Polymeric Network as the Novel Coating on Microneedles for Transdermal Drug Delivery Against Infectious Wounds

Coated microneedles (CMNs) are a minimally invasive platform for immediate-release transdermal drug delivery. However, the practical applications of CMNs have been significantly hindered by the challenges associated with complex formulations, single function, and limited drug loading capacity. This study has developed a spiderweb-shaped iron-coordinated polymeric nanowire network (Fe-IDA NWs). The resulting Fe-IDA NWs are endowed with a certain viscosity due to the synergy of multiple supramolecular interactions. This allows them to replace traditional polymeric thickeners as microneedle coatings. The Fe-IDA NWs-coated microneedles (Fe-IDA MNs) display rapid disintegration in the skin model, which also enables the swift diffusion of Fe-IDA NWs and their payloads into the deeper skin layers. Additionally, Fe-IDA MNs exhibit desirable enzymatic activity and potential antibacterial ability. Thus, Fe-IDA MNs can enhance the therapeutic efficacy against wound infection through synergistic effects, and avoid the overly complicated formulation and the release of nontherapeutic molecules of conventional CMNs. As a proof-of-concept, Fe-IDA MNs loaded with chlorin e6 showed a synergistic chemodynamic-photodynamic antibacterial effect in a methicillin-resistant Staphylococcus aureus-infected wound model in mice. Collectively, this work has significant implications for the future of CMNs-based transdermal drug delivery systems and expands the application fields of metal coordination polymer (MCP) materials.

Combination of ferroptosis and pyroptosis dual induction by triptolide nano-MOFs for immunotherapy of Melanoma

Immunotherapy has good potential to eradicate tumors in the long term. However, due to the low immunogenicity of tumor cells, current cancer immunotherapies are not effective. To address this limitation, we constructed a BSA-FA functionalized iron-containing metal-organic framework (TPL@TFBF) that triggers a potent systemic anti-tumor immune response by inducing ferroptosis and pyroptosis in tumor cells and releasing large quantities of damage-associated molecular patterns (DAMPs) to induce immunogenicity, and showing excellent efficacy against melanoma lung metastases in vivo. This nanoplatform forms a metal-organic framework through the coordination between tannic acid (TA) and Fe3+ and is then loaded with triptolide (TPL), which is coated with FA-modified BSA. The nanoparticles target melanoma cells by FA modification, releasing TPL, Fe3+ and TA. Fe3+ is reduced to Fe2+ by TA, triggering the Fenton reaction and resulting in ROS production. Moreover, TPL increases the production of intracellular ROS by inhibiting the expression of nuclear factor erythroid-2 related factor (Nrf2). Such simultaneous amplification of intracellular ROS induces the cells to undergo ferroptosis and pyroptosis, releasing large amounts of DAMPs, which stimulate antigen presentation of dendritic cells (DCs) and the proliferation of cytotoxic T lymphocytes (CD4+/CD8 + T cells) to inhibit tumor and lung metastasis. In addition, combining nanoparticle treatment with immune checkpoint blockade (ICB) further inhibits melanoma growth. This work provides a new strategy for tumor immunotherapy based on various combinations of cell death mechanisms.

Circumventing Physicochemical Barriers of Cyclometalated Gold(III) Dithiocarbamate Complexes with Protein-Based Nanoparticle Delivery to Enhance Anticancer Activity

Optimizing the bioavailability of drug candidates is crucial to successful drug development campaigns, especially for metal-derived chemotherapeutic agents. Nanoparticle delivery strategies can be deployed to overcome physicochemical limitations associated with drugs to improve bioavailability, pharmacokinetics, efficacy, and minimize toxicity. Biodegradable albumin nanoconstructs offer pragmatic solutions for drug delivery of metallodrugs with translational benefits in the clinic. In this work, we explored a logical approach to investigate and resolve the physicochemical drawbacks of gold(III) complexes with albumin nanoparticle delivery to improve solubility, enhance intracellular accumulation, circumvent premature deactivation, and enhance anticancer activity. We synthesized and characterized stable gold(III) dithiocarbamate complexes with a variable degree of cyclometalation such as phenylpyridine (C^N) or biphenyl (C^C) Au(III) framework and different alkyl chain lengths. We noted that extended alkyl chain lengths impaired the solubility of these complexes in biological media, thus adversely impacting potency. Encapsulation of these complexes in bovine serum albumin (BSA) reversed solubility limitations and improved cancer cytotoxicity by ∼25-fold. Further speciation and mechanism of action studies demonstrate the stability of the compounds and alteration of mitochondria bioenergetics, respectively. We postulate that this nanodelivery strategy is a relevant approach for translational small-molecule gold drug delivery.

Multisubcellular organelle-targeting nanoparticle for synergistic chemotherapy and photodynamic/photothermal tumor therapy

Background: The subcellular organelle-targeting strategy has attracted wide attention for a variety of reasons, including strong specificity, high accuracy, low dose administration and few side effects. It is an important and challenging task to explore the multisubcellular organelle-targeting strategy to achieve effective tumor treatment. Materials & methods: Using bovine serum albumin as a nanoreactor, BSA/Cu/NQ/IR780/DOX nanoparticles (NPs) were constructed via drug-induced protein self-assembly. Folic acid was then coupled to the surface of NPs to prepare folate receptor-targeted FA-BSA/Cu/NQ/IR780/DOX NPs. Results & conclusion: The FA-BSA/Cu/NQ/IR780/DOX NPs exhibit multifunctional properties, including multisubcellular organelle-targeting, induction of response release in the tumor microenvironment, fluorescence imaging capabilities and potential for synergistic chemotherapy and photodynamic/photothermal tumor therapy.

Activity of the old antimicrobial nitroxoline against Mycobacterium abscessus complex isolates

OBJECTIVES

The old antimicrobial nitroxoline is approved to treat urinary tract infection (UTI) and is currently rediscovered for treatment of drug resistant pathogens. Mycobacteria of the Mycobacterium abscessus complex (MYABS) are rapid-growing nontuberculous mycobacteria that are associated with difficult to treat infections of the lungs in patients with pulmonary disorders such as cystic fibrosis. In this study we assessed the in vitro activity of nitroxoline against molecularly characterized drug-resistant MYABS isolates from clinical samples to address potential repurposing of nitroxoline in difficult-to-treat MYABS infection.

METHODS

The isolates originated from clinical samples collected between 2010 and 2019 at the University Hospital of Cologne, Germany (N=16; 10/16 M. abscessus Spp. abscessus, 4/16 M. abscessus Spp. massiliense, 2/16 M. abscessus Spp. bolletii). Nitroxoline activity was compared to standard antimicrobials recommended for treatment of MYABS infection. For drug susceptibility testing of nitroxoline and comparators broth microdilution was performed based on current Clinical and Laboratory Standards Institute (CLSI) guidelines.

RESULTS

Nitroxoline yielded a MIC₉₀ of 4 mg/L (range 2-4 mg/L), which is two twofold dilutions below the current EUCAST susceptibility breakpoint of ≤ 16 mg/L (limited to uncomplicated UTI and Escherichia coli). Resistance to other antimicrobials was common in our cohort (16/16 isolates resistant to ciprofloxacin, imipenem and doxycycline; 12/16 isolates resistant to tobramycin; 9/16 isolates resistant to cefoxitin; 7/16 isolates resistant to clarithromycin; 2/16 isolates resistant to amikacin).

CONCLUSION

Nitroxoline has a promising in vitro activity against drug-resistant MYABS isolates. Future studies should investigate this finding with macrophage and in vivo models.

Gallium Metal-Organic Nanoparticles with Albumin-Stabilized and Loaded Graphene for Enhanced Delivery to HCT116 Cells

Background

Gallium (III) metal-organic complexes have been shown to have the ability to inhibit tumor growth, but the poor water solubility of many of the complexes precludes further application. The use of materials with high biocompatibility as drug delivery carriers for metal-organic complexes to enhance the bioavailability of the drug is a feasible approach.

Methods

Here, we modified the ligands of gallium 8-hydroxyquinolinate complex with good clinical anticancer activity by replacing the 8-hydroxyquinoline ligands with 5-bromo-8-hydroxyquinoline (HBrQ), and the resulting Ga(III) + HBrQ complex had poor water solubility. Two biocompatible materials, bovine serum albumin (BSA) and graphene oxide (GO), were used to synthesize the corresponding Ga(III) + HBrQ complex nanoparticles (NPs) BSA/Ga/HBrQ NPs and GO/Ga/HBrQ NPs in different ways to enhance the drug delivery of the metal complex.

Results

Both of BSA/Ga/HBrQ NPs and GO/Ga/HBrQ NPs can maintain stable existence in different solution states. In vitro cytotoxicity test showed that two nanomedicines had excellent anti-proliferation effect on HCT116 cells, which shown higher level of intracellular ROS and apoptosis ratio than that of cisplatin and oxaliplatin. In addition, the superior emissive properties of BSA/Ga/HBrQ NPs and GO/Ga/HBrQ NPs allow their use for in vivo imaging showing highly effective therapy in HCT116 tumor-bearing mouse models.

Conclusion

The use of biocompatible materials for the preparation of NPs against poorly biocompatible metal-organic complexes to construct drug delivery systems is a promising strategy that can further improve drug delivery and therapeutic efficacy.

Trend in biodegradable porous nanomaterials for anticancer drug delivery

In recent years, biodegradable nanomaterials have exhibited remarkable promise for drug administration to tumors due to their high drug-loading capacity, biocompatibility, biodegradability, and clearance. This review will discuss and summarize the trends in utilizing biodegradable nanomaterials for anticancer drug delivery, including biodegradable periodic mesoporous organosilicas (BPMOs) and metal-organic frameworks (MOFs). The distinct structure and features of BPMOs and MOFs will be initially evaluated, as well as their use as delivery vehicles for anticancer drug delivery applications. Then, the themes for the development of each material will be utilized to illustrate their drug delivery performance. Finally, the current obstacles and potential for future development as efficient drug delivery systems will be thoroughly reviewed. This article is categorized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease.

Functional insights to the development of bioactive material for combating bacterial infections

The emergence of antibiotic-resistant "superbugs" poses a serious threat to human health. Nanomaterials and cationic polymers have shown unprecedented advantages as effective antimicrobial therapies due to their flexibility and ability to interact with biological macromolecules. They can incorporate a variety of antimicrobial substances, achieving multifunctional effects without easily developing drug resistance. Herein, this article discusses recent advances in cationic polymers and nano-antibacterial materials, including material options, fabrication techniques, structural characteristics, and activity performance, with a focus on their fundamental active elements.

Nanoparticle-Mediated PRDX2 Inhibition for Specific Targeting of CHK2-Null Colorectal Cancer

Synthetic lethality is a pragmatic targeted cancer therapy approach in which cancer cells harboring genetic alterations are exploited for the specific killing of cancer cells. Earlier, we have established a synthetic lethal (SL) interaction between two genes that are CHK2 and PRDX2 in colorectal cancer (CRC) cells. The SL interaction between CHK2 and PRDX2 resulted in selective targeting of CHK2-defective CRC cells. N-Carbamoyl alanine (NCA) is a PRDX2 inhibitor and is a peptide-like organic compound, which degrades after oral administration in harsh gastric pH. To overcome the limitations of NCA, a chitosan-based nanocarrier was developed for the entrapment of NCA. In this study, we targeted the SL interaction between PRDX2 and CHK2 using NCA-loaded chitosan nanoparticles (NCA-Chit NPs) to selectively inhibit the CHK2-null HCT116 cells. NCA-Chit NPs were assessed for various physicochemical characterizations such as the hydrodynamic diameter (size), zeta potential, and polydispersity index using a Zetasizer. Additionally, morphological studies for the shape and size of NPs were confirmed by transmission electron microscopy, scanning electron microscopy, and atomic force microscopy. Cellular uptake of NPs was confirmed using confocal microscopy, which exhibited that nanoparticles were able to internalize into the HCT116 cells. Blank Chit NPs were found to be cytocompatible as they did not exert any cytotoxic effects on hTERT, L929, and Caco-2 cells (intestinal epithelial cells). Importantly, NCA-Chit NPs were quite hemocompatible also. In the form of an NCA-chitosan nanoformulation, the efficacy was enhanced by about 8 times compared to free form of NCA towards selective killing of CHK2-null HCT116 cells as compared to HCT116 cells. The chitosan-based nanoformulation for NCA was developed to augment the efficacy of the NCA for enhanced cell death of colorectal cancer cells having CHK2 defects.

Copper-based metal-organic frameworks for biomedical applications

Metal-organic frameworks (MOFs) are a class of important porous, crystalline materials composed of metal ions (clusters) and organic ligands. Owing to the unique redox chemistry, photochemical and electrical property, and catalytic activity of Cu^2+/+, copper-based MOFs (Cu-MOFs) have been recently and extensively explored in various biomedical fields. In this review, we first make a brief introduction to the synthesis of Cu-MOFs and their composites, and highlight the recent synthetic strategies of two most studied representatives, three-dimensional HKUST-1 and two-dimensional Cu-TCPP. The recent advances of Cu-MOFs in the applications of cancer treatment, bacterial inhibition, biosensing, biocatalysis, and wound healing are summarized and discussed. Furthermore, we propose a prospect of the future development of Cu-MOFs in biomedical fields and beyond.

In vitro Activity of Repurposed Nitroxoline Against Clinically Isolated Mycobacteria Including Multidrug-Resistant Mycobacterium tuberculosis

Antimicrobial treatment options for mycobacterial infections are limited due to intrinsic resistance and the emergence of acquired resistance in Mycobacterium tuberculosis. Isolates resisting first- and second line drugs are raising concerns about untreatable infections and make the development of new therapeutic strategies more pressing. Nitroxoline is an old oral antimicrobial that is currently repurposed for the treatment of urinary tract infection (UTI). In this study, we report the in vitro activity of nitroxoline against 18 clinical isolates of M. tuberculosis complex (MTBC) (M. tuberculosis N = 16, M. bovis BCG N = 1, M. bovis sp. bovis N = 1). Since nitroxoline achieves high concentrations in the urinary tract, we included all MTBC-isolates from urinary samples sent to our laboratory between 2008 and 2021 (University Hospital of Cologne, Germany). Isolates from other sources (N = 7/18) were added for higher sample size and for inclusion of drug-resistant M. tuberculosis isolates (N = 4/18). Based on our clinical routine the fluorescence-based liquid media system BACTEC MGIT 960 was used for susceptibility testing of nitroxoline and mainstay antitubercular drugs. Nitroxoline yielded a MIC₉₀ of 4 mg/L for MTBC. In all M. tuberculosis isolates nitroxoline MICs were at least two twofold dilutions below the current EUCAST susceptibility breakpoint of ≤16 mg/L (limited to E. coli and uncomplicated UTI). In vitro activity of nitroxoline can be considered excellent, even in multidrug-resistant isolates. Future studies with in vivo models should evaluate a potential role of nitroxoline in the treatment of tuberculosis in the era of drug resistance.

Recent advances in Cu(II)/Cu(I)-MOFs based nano-platforms for developing new nano-medicines

With increasing world population, life-span of humans and spread of viruses, myriad of diseases in human beings are becoming more and more common. Because of the interesting chemical and framework versatility and porosity of metal organic frameworks (MOFs) they find application in varied areas viz. catalysis, sensing, metal ion/gas storage, chemical separation, drug delivery, bio-imaging. This subclass of coordination polymers having interesting three-dimensional framework exhibits inordinate potential and hence may find application in treatment and cure of cancer, diabetes Alzheimer's and other diseases. The presented review focuses on the diverse mechanism of action, unique biological activity and advantages of copper-based metal organic framework (MOF) nanomaterials in medicine. Also, different methods used in the treatment of cancer and other diseases have been presented and the applications as well as efficacy of copper MOFs have been reviewed and discussed. Eventually, the current-status and potential of copper based MOFs in the field of anti-inflammatory, anti-bacterial and anti-cancer therapy as well as further investigations going on for this class of MOF-based multifunctional nanostructures in for developing new nano-medicines have been presented.

Aminocellulose-Grafted Polymeric Nanoparticles for Selective Targeting of CHEK2-Deficient Colorectal Cancer

We report the formulation of aminocellulose-grafted polymeric nanoparticles containing LCS-1 for synthetic lethal targeting of checkpoint kinase 2 (CHEK2)-deficient HCT116 colon cancer (CRC) cells to surpass the limitations associated with the solubility of LCS-1 (a superoxide dismutase inhibitor). Aminocellulose (AC), a highly biocompatible and biodegradable hydrophilic polymer, was grafted over polycaprolactone (PCL), and a nanoprecipitation method was employed for formulating nanoparticles containing LCS-1. In this study, we exploited the synthetic lethal interaction between SOD1 and CHEK2 for the specific inhibition of CHEK2-deficient HCT116 CRC cells using LCS-1-loaded PCL-AC NPs. Furthermore, the effects of formation of protein corona on PCL-AC nanoparticles were also assessed in terms of size, cellular uptake, and cell viability. LCS-1-loaded NPs were evaluated for their size, zeta potential, and polydispersity index using a zetasizer, and their morphological characteristics were assessed by transmission electron microscopy, scanning electron microscopy, and atomic force microscopy analyses. Cellular internalization using confocal microscopy exhibited that nanoparticles were uptaken by HCT116 cells. Also, nanoparticles were cytocompatible as they did not induce cytotoxicity in hTERT and HEK-293 cells. The LCS-1-loaded PCL-AC NPs were quite hemocompatible and were 240 times more selective in killing CHEK2-deficient cells as compared to CHEK2-proficient CRC cells. Moreover, PCL-AC NPs exhibited that the protein corona-coated nanoparticles were incubated in the human and fetal bovine sera as visualized by SDS-PAGE. A slight increment in hydrodynamic diameter was observed for corona-coated PCL-AC nanoparticles, and size increment was further confirmed by TEM. Corona-coated PCL-AC NPs also exhibited cellular uptake as demonstrated by flow cytometric analysis and did not cause cytotoxic effects on hTERT cells. The nanoformulation was developed to enhance therapeutic potential of the drug LCS-1 for enhanced lethality of colorectal cancer cells with CHEK2 deficiency.

Current Perspective on the Natural Compounds and Drug Delivery Techniques in Glioblastoma Multiforme

Simple Summary

Glioblastoma multiforme (GBM) is one of the belligerent neoplasia that metastasize to other brain regions and invade nearby healthy tissues. However, the treatments available are associated with some limitations, such as high variations in solid tumors and deregulation of multiple cellular pathways. The heterogeneity of the GBM tumor and its aggressive infiltration into the nearby tissues makes it difficult to treat. Hence, the development of multimodality therapy that can be more effective, novel, with fewer side effects, improving the prognosis for GBM is highly desired. This review evaluated the use of natural phytoconstituents as an alternative for the development of a new therapeutic strategy. The key aspects of GBM and the potential of drug delivery techniques were also assessed, for tumor site delivery with limited side-effects. These efforts will help to provide better therapeutic options to combat GBM in future.

Abstract

Glioblastoma multiforme (GBM) is one of the debilitating brain tumors, being associated with extremely poor prognosis and short median patient survival. GBM is associated with complex pathogenesis with alterations in various cellular signaling events, that participate in cell proliferation and survival. The impairment in cellular redox pathways leads to tumorigenesis. The current standard pharmacological regimen available for glioblastomas, such as radiotherapy and surgical resection following treatment with chemotherapeutic drug temozolomide, remains fatal, due to drug resistance, metastasis and tumor recurrence. Thus, the demand for an effective therapeutic strategy for GBM remains elusive. Hopefully, novel products from natural compounds are suggested as possible solutions. They protect glial cells by reducing oxidative stress and neuroinflammation, inhibiting proliferation, inducing apoptosis, inhibiting pro-oncogene events and intensifying the potent anti-tumor therapies. Targeting aberrant cellular pathways in the amelioration of GBM could promote the development of new therapeutic options that improve patient quality of life and extend survival. Consequently, our review emphasizes several natural compounds in GBM treatment. We also assessed the potential of drug delivery techniques such as nanoparticles, Gliadel wafers and drug delivery using cellular carriers which could lead to a novel path for the obliteration of GBM.

Human serum albumin-based doxorubicin prodrug nanoparticles with tumor pH-responsive aggregation-enhanced retention and reduced cardiotoxicity

Doxorubicin (DOX) is a widely-used anticancer drug, but its cardiotoxicity severely hampers its potency in chemotherapy. Herein, human serum albumin (HSA) is engaged as a biocompatible nanocarrier to load a pH-sensitive DOX prodrug, DMDOX, generating HSA-DMDOX nanoparticles via self-assembly driven by hydrophobic interactions. HSA-DMDOX disperses well in a physiological environment (∼40 nm) but aggregates in a tumor acidic microenvironment (pH 6.5, ∼140 nm) owing to the hydrophobicity increase of DMDOX by protonation of carboxylic groups. In vitro anticancer study showed that HSA-DMDOX exhibited enhanced cellular uptake by 4T1 cells and superior cytotoxicity in comparison to HSA-DOX nanoparticles. In vivo study suggested that HSA-DMDOX achieved long blood circulation, aggregation enhanced tumor retention, comparable antitumor efficacy and reduced cardiotoxicity relative to free DOX. Our work presents a facile and effective approach to delivering anthracyclines by HSA-based tumor pH-responsive nanoparticles with aggregation-enhanced tumor retention and reduced toxicity.

Targeted Nanoparticles for Co-delivery of 5-FU and Nitroxoline, a Cathepsin B Inhibitor, in HepG2 Cells of Hepatocellular Carcinoma

BACKGROUND

The first choice of treatment in Hepatocellular Carcinoma (HCC) is 5-fluorouracil (5-FU). Nitroxoline (NIT), a potent inhibitor of Cathepsin B, impairs tumor progression by decreased extracellular matrix degradation. The objective of the current project was designed to target nanoparticles for co-delivery of 5-FU and NIT in order to enhance the 5-FU cytotoxic effects and reduce the metastatic properties of HepG2 cells.

METHODS

5-FU and NIT were loaded in chitosan-chondroitin nanoparticles. To target the CD44 receptors of HepG2 cells, Hyaluronic Acid (HA) was conjugated to the chondroitin by adipic acid dihydrazide and the conjugation was confirmed by FTIR and 1HNMR. After physicochemical characterization and optimization of the processing variables, MTT assay was done on HepG2 and NIH3T3 cell lines to determine the cytotoxic properties of HA targeted nanoparticles. Migration of the cells was studied to compare the co-delivery of the drugs with each drug alone.

RESULTS

The optimized nanoparticles showed the particle size of 244.7±16.3nm, PDI of 0.30±0.03, drug entrapment efficiency of 46.3±5.0% for 5-FU and 75.1±0.9% for NIT. The drug release efficiency up to 8 hours was about 37.6±0.9% for 5-FU and 62.9±0.7% for NIT. The co-delivery of 5-FU and NIT in targeted nanoparticles showed significantly more cytotoxicity than the mixture of the two free drugs, non-targeted nanoparticles or each drug alone and reduced the IC50 value of 5-FU from 3.31±0.65μg/ml to 0.17±0.03μg/ml and the migration of HepG2 cells was also reduced to five-fold.

CONCLUSION

Co-delivery of 5-FU and NIT by HA targeted chitosan-chondroitin nanoparticles may be promising in HCC.

Synergy of hypoxia relief and heat shock protein inhibition for phototherapy enhancement

BACKGROUND

Phototherapy is a promising strategy for cancer therapy by reactive oxygen species (ROS) of photodynamic therapy (PDT) and hyperthermia of photothermal therapy (PTT). However, the therapeutic efficacy was restricted by tumor hypoxia and thermal resistance of increased expression of heat shock protein (Hsp). In this study, we developed albumin nanoparticles to combine hypoxia relief and heat shock protein inhibition to overcome these limitations for phototherapy enhancement.

RESULTS

Near-infrared photosensitizer (IR780) and gambogic acid (GA, Hsp90 inhibitor) were encapsulated into albumin nanoparticles via hydrophobic interaction, which was further deposited MnO2 on the surface to form IGM nanoparticles. Both in vitro and in vivo studies demonstrated that IGM could catalyze overexpress of hydrogen peroxide to relive hypoxic tumor microenvironment. With near infrared irradiation, the ROS generation was significantly increase for PDT enhancement. In addition, the release of GA was promoted by irradiation to bind with Hsp90, which could reduce cell tolerance to heat for PTT enhancement. As a result, IGM could achieve better antitumor efficacy with enhanced PDT and PTT.

CONCLUSION

This study develops a facile approach to co-deliver IR780 and GA with self-assembled albumin nanoparticles, which could relive hypoxia and suppress Hsp for clinical application of cancer phototherapy.

Improvement in the Pharmacological Profile of Copper Biological Active Complexes by Their Incorporation into Organic or Inorganic Matrix

Every year, more Cu(II) complexes are proven to be biologically active species, but very few are developed as drugs or entered in clinical trials. This is due to their poor water solubility and lipophilicity, low stability as well as in vivo inactivation. The possibility to improve their pharmacological and/or oral administration profile by incorporation into inorganic or organic matrix was studied. Most of them are either physically encapsulated or conjugated to the matrix via a moiety able to coordinate Cu(II). As a result, a large variety of species were developed as delivery carriers. The organic carriers include liposomes, synthetic or natural polymers or dendrimers, while the inorganic ones are based on carbon nanotubes, hydrotalcite and silica. Some hybrid organic-inorganic materials based on alginate-carbonate, gold-PEG and magnetic mesoporous silica-Schiff base were also developed for this purpose.

Recent development of amorphous metal coordination polymers for cancer therapy

Nanoscale metal coordination polymers (NCPs), built from metal ions and organic ligands, have attracted tremendous interest in biomedical applications. This is mainly due to their mesoporous structure, tunable size and morphology and versatile functionality. NCPs can be further divided into nanoscale metal-organic frameworks (NMOFs) and amorphous coordination polymer particles (ACPPs) depending on their structural crystallinity. NMOFs as nanocarriers have been extensively reviewed. However, the highlights of ACPPs as theranostic nanoplatforms are still limited. In this review, the recent progress of ACPPs as theranostic nanoplatforms is summarized based on what types of organic linkers used. The ACPPs are divided into three main parts: photosensitizers-based ACPPs, chemical drugs-based ACPPs, and biomolecules-based ACPPs. Finally, the prospects and challenges of the ACPPs for enhanced biomedical applications are also discussed. STATEMENT OF SIGNIFICANCE: Over the last decades, amorphous metal coordination polymers (ACPPs), constructed by metal ions and organic linkers, have attracted enormous interest in cancer treatment owing to their high drug loading capability, facile synthetic procedures, low long-term toxicity, and mild preparation conditions. In this review, we highlight the recent progress of ACPPs for biomedical application based on different types of organic building blocks including photosensitizers, chemical drugs, and biomolecules. Moreover, the prospects and challenges of ACPPs for clinical application are also discussed. We hope this review entitled "Recent development of amorphous metal coordination polymers for cancer therapy" would arise the researchers' interest in this field to accelerate their clinical application in cancer therapy.

Current Perspectives on Therapies, Including Drug Delivery Systems, for Managing Glioblastoma Multiforme

Glioblastoma multiforme (GBM), a standout among the most dangerous class of central nervous system (CNS) cancer, is most common and is an aggressive malignant brain tumor in adults. In spite of developments in modality therapy, it remains mostly incurable. Consequently, the need for novel systems, strategies, or therapeutic approaches for enhancing the assortment of active agents meant for GBM becomes an important criterion. Currently, cancer research focuses mainly on improving the treatment of GBM via diverse novel drug delivery systems. The treatment options at diagnosis are multimodal and include radiation therapy. Moreover, significant advances in understanding the molecular pathology of GBM and associated cell signaling pathways have opened opportunities for new therapies. Innovative treatment such as immunotherapy also gives hope for enhanced survival. The objective of this work was to collect and report the recent research findings to manage GBM. The present review includes existing novel drug delivery systems and therapies intended for managing GBM. Reported novel drug delivery systems and diverse therapies seem to be precise, secure, and relatively effective, which could lead to a new track for the obliteration of GBM.

Ultrasmall Ag2Te Quantum Dots with Rapid Clearance for Amplified Computed Tomography Imaging and Augmented Photonic Tumor Hyperthermia

With the fast development of nanomedicine, the imaging-guided and photo-induced cancer monotherapies can efficiently eliminate tumor lesions, which are strongly dependent on the construction of versatile theranostic nanoplatforms. Among diverse photo-converting nanoplatforms, silver chalcogenide nanoparticles feature high biocompatibility, narrow band gaps, and tunable optical properties, yet Ag₂Te-based nanosystems are still at a proof-of-concept stage, and the exploration of Ag₂Te-based nanosystems suitable for photonic tumor hyperthermia is challenging. Herein, we report on the construction of versatile ultrasmall Ag₂Te quantum dots (QDs) via a facile biomineralization strategy. Especially, these Ag₂Te QDs with negligible toxicity and excellent biocompatibility were developed for X-ray computed tomography (CT) imaging-guided photonic tumor hyperthermia by near-infrared (NIR) activation. The fabricated Ag₂Te QDs exhibited a high tumor suppression rate (94.3%) on 4T1 breast tumor animal models due to the high photothermal-conversion efficiency (50.5%). Mechanistically, Ag₂Te QDs were promising potential CT imaging agents for imaging guidance and monitoring during photonic hyperthermia. Importantly, Ag₂Te QDs were rapidly eliminated from the body via feces and urine because of their ultrasmall sizes. This work not only broadens the biomedical applications of silver chalcogenide-based theranostic nanosystems but also provides the paradigm of theranostic nanosystems with a photonic tumor hyperthermia effect and outstanding contrast enhancement of high-performance CT imaging.

Zwitterionic Unimolecular Micelles with pH and Temperature Response: Enhanced In Vivo Circulation Stability and Tumor Therapeutic Efficiency

Circulation stability in vivo and stimuli-responsiveness under a tumor microenvironment of the polymeric prodrug micellar drug delivery systems are very critical to improve the tumor therapeutic efficiency. In this study, a series of polyamidoamine (PAMAM)-graft-poly(2-(diethylamino) ethyl methacrylate) (PDEAEMA)-block-poly(betaine sulfonate) (PSBMA) (PDS) unimolecular micelles were prepared via atom transfer radical polymerization. PAMAM served as a hydrophobic core to load the drug, the PDMAEMA segment was a middle layer to provide both thermo- and pH-sensitivity, whereas the PSMBA shell layer was used to improve the stability of the unimolecular micelles. The PDS exhibited a spherical structure with the size of 10-20 nm at pH 7.4. PDS micelles had excellent stability to resist the large volume liquid dilution. Moreover, it exhibited excellent stability in a complex biological microenvironment because of a superhigh antiprotein adhesion capacity of the PSBMA shell layer compared with PAMAM micelles. Drug release studies confirmed that the DOX can remain in the PDS micelles at pH 7.4 and 37 °C, whereas it can rapidly be released when the pH decreases to 5.0 and/or the temperature increases to 40 °C. In vitro studies suggested that the PDS drug delivery system can effectivity induce apoptosis and inhibit the proliferation of cancer cells. In vivo studies suggested that the PDS micelles prolonged the circulation time, decreased the side effects, and increased the antitumor efficacy. Therefore, the prepared PDS micelles are a potential anticancer drug delivery carrier for cancer therapy.

Metal Organic Frameworks as Drug Targeting Delivery Vehicles in the Treatment of Cancer

: In recent years, metal organic frameworks (MOFs) have been widely developed as vehicles for the effective delivery of drugs to tumor tissues. Due to the high loading capacity and excellent biocompatibility of MOFs, they provide an unprecedented opportunity for the treatment of cancer. However, drugs which are commonly used to treat cancer often cause side effects in normal tissue accumulation. Therefore, the strategy of drug targeting delivery based on MOFs has excellent research significance. Here, we introduce several intelligent targeted drug delivery systems based on MOFs and their characteristics as drug-loading systems, and the challenges of MOFs are discussed. This article covers the following types of MOFs: Isoreticular Metal Organic Frameworks (IRMOFs), Materials of Institute Lavoisier (MILs), Zeolitic Imidazolate Frameworks (ZIFs), University of Oslo (UiOs), and MOFs-based core-shell structures. Generally, MOFs can be reasonably controlled at the nanometer size to effectively achieve passive targeting. In addition, different ligands can be modified on MOFs for active or physicochemical targeting. On the one hand, the targeting strategy can improve the concentration of the drugs at the tumor site to improve the efficacy, on the other hand, it can avoid the release of the drugs in normal tissues to improve safety. Despite the challenges of clinical application of MOFs, MOFs have a number of advantages as a kind of smart delivery vehicle, which offer possibilities for clinical applications.

Protein-based nanoplatforms for tumor imaging and therapy

Cancer is one of the leading causes of death all over the world. The development of nanoplatform provides a promising strategy for the diagnosis and treatment of cancer. As the foundation of the nanoplatform, the composition of nanocarrier decides the basic properties. Protein exists in all kinds of life and participates in any life activities, having great potentials to serve as a nanocarrier because of its excellent biocompatibility, abundance of functional groups, and inherent biological activity. As a result, protein-based nanoplatforms have evoked extensive interests for tumor imaging and therapy. This review presents the latest progresses on the advancement of protein-based nanoplatforms, introducing the most common protein nanocarriers (such as human/bovine serum albumin, ferritin, human transferrin) thoroughly including their physiochemical properties and specific applications. Also, other kinds of protein are briefly involved. Finally, the prospects and challenges of the development of protein-based nanoplatforms are summarized. This article is categorized under: Biology-Inspired Nanomaterials > Protein and Virus-Based Structures Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease.

Stability issues and approaches to stabilised nanoparticles based drug delivery system

Nanoparticles form the fundamental building blocks for many exciting applications in various scientific disciplines due to its unique features such as large surface to mass ratio, targeting potential, ability to adsorbed and carry other compound which makes them suitable for biomedical applications. However, the problem of the large-scale synthesis of nanoparticles remains challenging due to physical instability associated with nanoparticles which lead to generation of aggregates particles with high polydispersity index (PDI) indicating low particle homogeneity and eventually loss of their special nanoscale properties. The stabilisation concept can be generated by repulsive electrostatic force, which nanoparticles experience, when they are surrounded by a double layer of electric charges. Selection of proper stabiliser will govern the stability of NPs and ultimately development of optimised drug delivery system. This review summarises mechanism of physical instability issues likely to be encountered during the development of nanoformulations. It also discusses potential stabilising agents used so far and their mechanism in achieving stable nanosystems.

Dual Stable Nanomedicines Prepared by Cisplatin-Crosslinked Camptothecin Prodrug Micelles for Effective Drug Delivery

A polymer micelle-based drug delivery system has faced many challenges due to the lack of stability especially after being diluted in blood, resulting in a premature release. Herein, we developed camptothecin (CPT)-conjugated prodrug (CPTP) micelles in which CPT was grafted to the poly(ethylene glycol)-poly(glutamic acid) block copolymer via a disulfide bond linker for a redox-triggered drug release. Then, the cisplatin (CDDP)-crosslinked CPT-prodrug micelles (CPTP/CDDP) with a hybrid complex as a stable structure were successfully established via the CDDP (Pt)-carboxyl (COOH) chelate interaction. The resulting dual CPTP/CDDP had an average hydrodynamic radius of about 50 nm with a narrow distribution, which was conducive to the promotion of solid tumor accumulation. Importantly, CPT chemical bonding to the polymer backbone obviously stabilizes the CPT-prodrug micelles and prolongs their circulation time. Moreover, both CPT and CDDP are clinically used antitumor drugs; CDDP not only behaves as an ancillary anticarcinogen but also serves as a crosslinker to restrain the untimely burst release of CPT and to achieve synergistic antitumor efficacy. In addition, the CPTP/CDDP also exhibited a sustained reduction responsive release of CPT accompanied by the dissociation of the CDDP-COOH complex. This design ingeniously solved the contradiction between the stability and release of polymer micelle-based nanomedicines. Both in vitro and in vivo tests demonstrated an amazing antineoplastic efficacy compared with free drugs (CPT or CDDP) and just their physical mixing, indicating great promise for cancer treatment.