Mitochondria and Nucleus Dual Delivery System To Overcome DOX Resistance

Mitochondria-Targeted Liposomes for Drug Delivery to Tumor Mitochondria

The special bilayer structure of mitochondrion is a promising therapeutic target in the diagnosis and treatment of diseases such as cancer and metabolic diseases. Nanocarriers such as liposomes modified with mitochondriotropic moieties can be developed to send therapeutic molecules to mitochondria. In this study, DSPE-PEG-TPP polymer conjugate was synthesized and used to prepare mitochondria-targeted liposomes (TPPLs) to improve the therapeutic index of chemotherapeutic agents functioning in mitochondria and reduce their side effects. Doxorubicin (Dox) loaded-TPPL and non-targeted PEGylated liposomes (PPLs) were prepared and compared based on physicochemical properties, morphology, release profile, cellular uptake, mitochondrial localization, and anticancer effects. All formulations were spherically shaped with appropriate size, dispersity, and zeta potential. The stability of the liposomes was favorable for two months at 4 °C. TPPLs localize to mitochondria, whereas PPLs do not. The empty TPPLs and PPLs were not cytotoxic to HCT116 cells. The release kinetics of Dox-loaded liposomes showed that Dox released from TPPLs was higher at pH 5.6 than at pH 7.4, which indicates a higher accumulation of the released drug in the tumor environment. The half-maximal inhibitory concentration of Dox-loaded TPPLs and PPLs was 1.62-fold and 1.17-fold lower than that of free Dox due to sustained drug release, respectively. The reactive oxygen species level was significantly increased when HCT116 cells were treated with Dox-loaded TPPLs. In conclusion, TPPLs may be promising carriers for targeted drug delivery to tumor mitochondria.

Recent Advances in Doxorubicin Formulation to Enhance Pharmacokinetics and Tumor Targeting

Doxorubicin (DOX), a widely used drug in cancer chemotherapy, induces cell death via multiple intracellular interactions, generating reactive oxygen species and DNA-adducted configurations that induce apoptosis, topoisomerase II inhibition, and histone eviction. Despite its wide therapeutic efficacy in solid tumors, DOX often induces drug resistance and cardiotoxicity. It shows limited intestinal absorption because of low paracellular permeability and P-glycoprotein (P-gp)-mediated efflux. We reviewed various parenteral DOX formulations, such as liposomes, polymeric micelles, polymeric nanoparticles, and polymer-drug conjugates, under clinical use or trials to increase its therapeutic efficacy. To improve the bioavailability of DOX in intravenous and oral cancer treatment, studies have proposed a pH- or redox-sensitive and receptor-targeted system for overcoming DOX resistance and increasing therapeutic efficacy without causing DOX-induced toxicity. Multifunctional formulations of DOX with mucoadhesiveness and increased intestinal permeability through tight-junction modulation and P-gp inhibition have also been used as orally bioavailable DOX in the preclinical stage. The increasing trends of developing oral formulations from intravenous formulations, the application of mucoadhesive technology, permeation-enhancing technology, and pharmacokinetic modulation with functional excipients might facilitate the further development of oral DOX.

Thermosensitive Biomimetic Hybrid Membrane Camouflaged Hollow Gold Nanoparticles for NIR-Responsive Mild-Hyperthermia Chemo-/Photothermal Combined Tumor Therapy

As an appealing biomimetic strategy for various medical applications, cell membrane coating lacks sensitive on-demand breaking capability. Herein, we incorporated thermosensitive lipid (TSL) membrane into red blood cell (RBC) and MCF-7 cancer cell (MC) hybrid membrane ([RBC-MC]M) vesicles. The [RBC-MC-TSL]M was coated onto doxorubicin (Dox)-loaded hollow gold nanoparticles to enhance chemo-/photothermal combined tumor therapy at a mild hyperthermia temperature (≤49 °C). Double-layer coating with TSL and [RBC-MC-TSL]M as the inner and outer layer, respectively, presented better antileakage and higher NIR-responsivity than single-layer coating. The Dox release ratio upon NIR laser irradiation (≤49 °C) was 74.6%, much higher than that (33.5%) without NIR laser. The nanodrug can be efficiently and specifically taken up by MCF-7 cells. In addition, the nanodrug exhibited excellent tumor-targeting property, with 4.08- and 1.12-times Dox accumulation in MCF-7 tumors compared to free Dox and [RBC-MC]M-coated counterpart, respectively. Most importantly, TSL incorporation significantly enhanced NIR-responsive antitumor efficiency, with tumor growth inhibition ratio increased from 35.1% to 48.6% after a single dose administration. Besides, the nanodrug exhibited very good biocompatibility. Camouflaging nanoparticles with the thermosensitive biomimetic hybrid membrane provides a painless and promisingly clinical-applicable approach for effective chemo-/photothermal combined mild-hyperthermia tumor therapy.

An Acid-Sensitive Nanofiber Conjugate Based on a Short Aromatic Peptide for Targeted Delivery of Doxorubicin in Liver Cancer

Purpose

This study aimed to construct a DOX conjugate with liver tumor targeting and acid sensitivity based on a short aromatic peptide FFYEE, which could amplify the tumor inhibition efficacy of DOX and alleviate tissue toxicity.

Methods

A novel DOX-peptide conjugate, D-gal-FFYEE-hyd-DOX, was constructed by linking DOX to the side chain of FFYEE with acid-sensitive hydrazone bond and by modifying the C-terminal of peptide with α-D-galactosamine (D-gal) as targeting ligand. The structure of D-gal-FFYEE-hyd-DOX was characterized by mass spectrometry, infrared spectroscopy (IR), and UV-Vis spectroscopy (UV-Vis). The assembly characteristics of pentapeptide FFYEE and D-gal-FFYEE-hyd-DOX were observed by transmission electron microscope (TEM). In vitro drug release, cytotoxicity, endocytosis, in vivo antitumor experiment and histopathology analysis were investigated.

Results

Peptide FFYEE endowed the D-gal-FFYEE-hyd-DOX with self-assembly performance and improved biocompatibility. D-gal-FFYEE-hyd-DOX can self-assemble into nanofibers with a diameter of ~ 40 nm in neutral aqueous solution and significantly reduced the cytotoxicity of free DOX to L02 cells. In vitro drug release results showed that D-gal-FFYEE-hyd-DOX had acid sensitivity and controlled release characteristics. The cytotoxicity and endocytosis investigations confirmed that D-gal-FFYEE-hyd-DOX enhanced the cellular uptake of DOX and inhibition effect on HepG2 cells. In vivo antitumor experiment indicated that D-gal-FFYEE-hyd-DOX could significantly inhibit the growth of liver tumor in mice and reduce the side effects of DOX.

Conclusion

The conjugate D-gal-FFYEE-hyd-DOX with liver tumor targeting and acid sensitivity has the characteristics of strong tumor inhibition and low toxicity, hinting the great clinical application potential for targeted delivery of DOX in cancer treatment.

Novel Prodrug Supramolecular Nanoparticles Capable of Rapid Mitochondrial-Targeted and ROS-Responsive for Pancreatic Cancer Therapy

Mitochondrial dysfunction is a feature of cancer cells and targeting cancer mitochondria has emerged as a promising anticancer therapy. In this study, a novel mitochondria-targeted and ROS-responsive drug delivery nanoplatform...

Concurrent impairment of nucleus and mitochondria for synergistic inhibition of cancer metastasis

Cancer metastasis, which increases the mortality in a short period of time, has been considered as the main challenge in tumor treatment. However, tumor growth suppression also should not be ignored in cancer metastasis treatment. Recently, accumulating evidences have suggested that mitochondria play an important role in mitigating caner metastasis. Nucleus, as the repository of genetic information, plays a key role in cell proliferation. However, it remains elusive that the concurrent impairment of nucleus and mitochondria may achieve better anti-tumor and anti-metastatic effects. Here, we designed a mitochondria-penetrating peptide modified doxorubicin (MPP-Dox) loaded N-(2-hydroxypropyl) methacrylamide (HPMA) copolymer conjugates (PM), as well as a nuclear accumulating HPMA copolymer Dox conjugates (PN) by the nuclear tendency of Dox. After co-delivering the two copolymers (abbreviation for PMN), PM promoted cell apoptosis and inhibited tumor metastasis by damaging mitochondria, whereas PN suppressed cell proliferation and promoted apoptosis by destroying nucleus. Importantly, PM and PN complemented each other as expected. The mitochondrial dysfunction and tumor metastasis inhibition of PM was improved by PN, while cell proliferation suppression and apoptosis by nucleus destroying of PN was enhanced by PM. As a result, tumor growth of breast cancer 4T1 cells in vivo was significantly restrained and lung metastasis was potently decreased and almost eradicated, fully reflecting the advantages of organelle targeting combination therapy. As a consequence, our work showed that concurrent impairment of nucleus and mitochondria was feasible and beneficial to metastatic cancer treatment.

A pH-sensitive drug delivery system based on hyaluronic acid co-deliver doxorubicin and aminoferrocene for the combined application of chemotherapy and chemodynamic therapy

Doxorubicin is a broad-spectrum antineoplastic drug used in tumor therapy, its clinical application is limited by side effects on normal tissues. In this article, a pH-responsive drug delivery system (NPs(DOX/AFc)) with co-delivers doxorubicin (DOX) and aminoferrocene (AFc) was prepared by a two-step synthesis method including the oxidation of hyaluronic acid and Schiff base reaction. NPs(DOX/AFc) can be used in combination therapy of chemodynamic therapy (CDT) and chemotherapy (CT), thus the dosage of the chemotherapeutic drug DOX was reduced. The drug release behavior of NPs(DOX/AFc) in vitro showed that acid-responsive drug releases under the endosomal/lysosomal environment were 56.5 % of DOX and 61.8 % of AFc. In vitro toxicity experiments showed that DOX and AFc had synergistic effects (CI = 0.878). The results of intracellular ROS measurement and the mitochondrial membrane potential analysis showed that in tumor cells NPs(DOX₄/AFc) induced more production of reactive oxygen species and more loss of the mitochondrial membrane potential. In short, this co-delivery system based on polymer prodrugs provides a new idea for the combined application of CT and CDT.

Overexpression of Kininogen-1 aggravates oxidative stress and mitochondrial dysfunction in DOX-induced cardiotoxicity

BACKGROUND

Doxorubicin (DOX) is a widely used cancer chemotherapeutic drug with cardiotoxicity effect limiting its clinical use. DOX induced cardiotoxicity is mediated by oxidative stress and mitochondrial damage. Kininogen-1(KNG1) is an important pro-inflammatory and pro-oxidant factor, and studies have found that it can aggravate lung and brain damage. However, it has not been known in terms of cardiotoxicity. Therefore, the purpose of this study is to understand the mechanism of KNG1 in DOX-induced heart injury.

METHODS

C57 mice were selected for intraperitoneal injection of DOX. The model was successfully established, and fresh ventricular tissues were isolated from the ctrl group and the DOX group for mass spectrometry analysis to screen for differentially expressed proteins. Nuclear Factor-Like 2 (Nrf2), Heme Oxygenase 1 (HO-1), 4-Hydroxynonenal (4-HNE) were used to evaluate oxidative stress level, Cytochrome C Oxidase Subunit 4 (COX4) was used to evaluate mitochondria function. Mitochondrial inner membrane potential (ΔΨm) was monitored with JC-1 fluorescence.

RESULTS

KNG1 was identified as a core gene which was highly expressed in the DOX myocardial injury model. Following this, an overexpression adenovirus was constructed, and KNG1 was overexpressed in vivo (mice) and in vitro (neonatal mouse cardiomyocytes (NMCMs)). It was found that overexpression of KNG1 can aggravate heart oxidative stress and mitochondrial damage. Besides, a knockdown KNG1 model was constructed, and the low expression of KNG1 was performed in cytology. It was found that knockdown of KNG1 can improve cardiomyocyte oxidative stress and mitochondrial damage caused by DOX. Nrf2 is an important antioxidant factor. Further, following KNG1 knock down, Nrf2 was also knocked down, and found that its cardiomyocyte protective effect was weakened.

CONCLUSION

The overexpression of KNG1 aggravates the oxidative stress and mitochondrial damage of the heart in vivo and in vitro, which might play a role by regulating Nrf2, providing a therapeutic target for DOX-induced cardiotoxicity.

Smart Design of Nanomaterials for Mitochondria-Targeted Nanotherapeutics

Mitochondria are the powerhouse of cells. They are vital organelles that maintain cellular function and metabolism. Dysfunction of mitochondria results in various diseases with a great diversity of clinical appearances. In the past, strategies have been developed for fabricating subcellular-targeting drug-delivery nanocarriers, enabling cellular internalization and subsequent organelle localization. Of late, innovative strategies have emerged for the smart design of multifunctional nanocarriers. Hierarchical targeting enables nanocarriers to evade and overcome various barriers encountered upon in vivo administration to reach the organelle with good bioavailability. Stimuli-responsive nanocarriers allow controlled release of therapeutics to occur at the desired target site. Synergistic therapy can be achieved using a combination of approaches such as chemotherapy, gene and phototherapy. In this Review, we survey the field for recent developments and strategies used in the smart design of nanocarriers for mitochondria-targeted therapeutics. Existing challenges and unexplored therapeutic opportunities are also highlighted and discussed to inspire the next generation of mitochondrial-targeting nanotherapeutics.

Zwitterionic Polymer Micelles with Dual Conjugation of Doxorubicin and Curcumin: Synergistically Enhanced Efficacy against Multidrug-Resistant Tumor Cells

This paper reports a novel redox-sensitive micellar system for the co-delivery of doxorubicin (Dox) and a chemosensitizer (curcumin, Cur) to overcome the multidrug resistance (MDR) in cancer cells. Dox and Cur were co-conjugated onto a zwitterionic polymer, poly(carboxybetaine) (pCB), to form Cur-pCB-Dox that self-assembled into stable micelles (164.2 ± 4.8 nm). Single-drug conjugates (pCB-Dox and pCB-Cur) were prepared for comparisons. Compared to the high half-maximal inhibitory concentration (IC₅₀) of Dox (437.2 μg/mL), the IC₅₀ value of pCB-Dox (14.1 μg/mL) was only 1/33 that of Dox. Confocal laser scanning microscopy and flow cytometry revealed the greatly enhanced cell uptake of the conjugate due to the enhanced permeability and retention effect of tumor cells on the micellar conjugate. Co-delivery of pCB-Dox with pCB-Cur further reduced the IC₅₀ value by 37% (8.9 μg/mL). More importantly, Cur-pCB-Dox exhibited the strongest cytotoxicity against MCF-7/Adr cells (IC₅₀, 5.87 μg/mL) because the co-delivered Dox and Cur on one carrier specifically transported into the same cells, which inhibited the efflux of Dox by Cur, led to a higher intracellular Dox concentration and made the drugs exert synergistic effects at the targeting regions. The results proved the zwitterionic micelles as promising drug co-delivery vehicles for fighting against MDR.

Trackable Water-Soluble Prodrug Micelles Capable of Rapid Mitochondrial-Targeting and Alkaline pH-Responsive Drug Release for Highly Improved Anticancer Efficacy

A trackable water-soluble prodrug conjugate possessing high contents of chlorambucil (Cb) and triphenylphosphonium cation (TPP) was designed and developed after TPP modification on the "branch" of amphipathic prodrugs based on convenient synthesis of heterobifunctional clickable poly(ethylene glycol) (PEG). The aqueous self-assembly of fluorescent polymeric micelles along precise composition can be easily prepared after directly dissolved (DD) in aqueous solution, and exhibit superior cytotoxicity to cancer cells along with highly improved selectivity and sensitivity because of their rapid mitochondrial-targeting and alkaline pH-responsive drug release capabilities. Notably, efficient codelivery of doxorubicin (DOX) for synergistic targeted drug delivery and cancer therapy was achieved.

Mitochondria and Nuclei Dual-Targeted Hollow Carbon Nanospheres for Cancer Chemophotodynamic Synergistic Therapy

Dual-targeted nanoparticles are gaining increasing importance as a more effective anticancer strategy by attacking double key sites of tumor cells, especially in chemophotodynamic therapy. To retain the nuclei inhibition effect and enhance doxorubicin (DOX)-induced apoptosis by mitochondrial pathways simultaneously, we synthesized the novel nanocarrier (HKH) based on hollow carbon nitride nanosphere (HCNS) modified with hyaluronic acid (HA) and the mitochondrial localizing peptide D[KLAKLAK]2 (KLA). DOX-loaded HKH nanoparticles (HKHDs) showed satisfactory drug-loading efficiency, excellent solubility, and very low hemolytic effect. HA/CD44 binding and electrostatic attraction between positively charged KLA and A549 cells facilitated HKHD uptake via the endocytosis mechanism. Acidic microenvironment, hyaluronidase, and KLA targeting together facilitate doxorubicin toward the mitochondria and nuclei, resulting in apoptosis, DNA intercalation, cell-cycle arrest at the S phase, and light-induced reactive oxygen species production. Intravascular HKHD inhibited tumor growth in A549-implanted mice with good safety. The present study, for the first time, systemically reveals biostability, targetability, chemophotodynamics, and safety of the functionalized novel HKHD.

Mitochondria and nucleus delivery of active form of 10-hydroxycamptothecin with dual shell to precisely treat colorectal cancer

AIM

The objective of this study was to deliver a ring-closed form of 10-hydroxycamptothecin (HCPT) to the mitochondria and nucleus to treat colorectal cancer.

MATERIALS & METHODS

HCPT-loaded nanoparticle HCPT@PLGA-PEG_2k-triphenylphosphonium/PLGA-hyd-PEG_4k-folic acid (PT/PHF) and HCPT@PT/PLGA-SS-PEG_4k-folic acid (PSF) were prepared by using emulsion-solvent evaporation method.

RESULTS

In vitro experimental results indicated HCPT@PT/PHF and HCPT@PT/PSF maintained a large amount of HCPT in active form, and delivered more HCPT to the nucleus and mitochondria of the tumor cell, which resulted in the enhancement of cytotoxicity of HCPT. In vivo experimental results indicated that HCPT@PT/PHF and HCPT@PT/PSF delivered more ring-closed form of HCPT to tumor tissue, which led to strong antitumor activity.

CONCLUSION

HCPT@PT/PHF and HCPT@PT/PSF could enhance therapeutic efficacy of HCPT to colorectal cancer.

Psoralen-loaded lipid-polymer hybrid nanoparticles enhance doxorubicin efficacy in multidrug-resistant HepG2 cells

Background

Psoralen (PSO), a major active component of Psoralea corylifolia, has been shown to overcome multidrug resistance in cancer. A drug carrier comprising a lipid-monolayer shell and a biodegradable polymer core for sustained delivery and improved efficacy of drug have exhibited great potential in efficient treatment of cancers.

Methods

The PSO-loaded lipid polymer hybrid nanoparticles were prepared and characterized. In vitro cytotoxicity assay, cellular uptake, cell cycle analysis, detection of ROS level and mitochondrial membrane potential (ΔΨm) and western blot were performed.

Results

The P-LPNs enhanced the cytotoxicity of doxorubicin (DOX) 17-fold compared to free DOX in multidrug resistant HepG2/ADR cells. Moreover, P-LPNs displayed pro-apoptotic activity, increased levels of ROS and depolarization of ΔΨm. In addition, there were no signifi-cant effects on cellular uptake of DOX, cell cycle arrest, or the expression of P-glycoprotein. Mechanistic studies suggested that P-LPNs enhanced DOX cytotoxicity by increased release of cytochrome c and enhanced caspase3 cleavage, causing apoptosis in HepG2/ADR cells.

Conclusion

The lipid-polymer hybrid nanoparticles can be considered a powerful and promising drug delivery system for effective cancer chemotherapy.

Doxorubicin-loaded nanoscale metal–organic framework for tumor-targeting combined chemotherapy and chemodynamic therapy

DMH NPs were prepared and could effectively induce MCF-7 cell death through the combination of chemotherapy and chemodynamic therapy.

Cancer cell membrane-cloaked mesoporous silica nanoparticles with a pH-sensitive gatekeeper for cancer treatment

Nanoparticular drug delivery system (NDDS) has great potential for enhancing the efficacy of traditional chemotherapeutic drugs. However, it is still a great challenge to fabricate a biocompatible NDDS with simple structure capable of optimizing therapeutic efficacy, such as high tumor accumulation, suitable drug release profile (e.g. no premature drug leakage in normal physiological conditions while having a rapid release in cancer cells), low immunogenicity, as well as good biocompatibility. In this work, a simple core/shell structured nanoparticle was fabricated for prostate cancer treatment, in which a mesoporous silica nanoparticle core was applied as a container to high-efficiently encapsulate drugs (doxorubicin, DOX), CaCO₃ interlayer was designed to act as sheddable pH-sensitive gatekeepers for controlling drug release, and cancer cell membrane wrapped outlayer could improve the colloid stability and tumor accumulation capacity. In vitro cell experiments demonstrated that the as-prepared nanovehicles (denoted as DOX/MSN@CaCO₃@CM) could be efficiently uptaken by LNCaP-AI prostate cancer cells and even exhibited a better anti-tumor efficiency than free DOX. In addition, Live/Dead cell detection and apoptosis experiment demonstrated that MSN/DOX@CaCO₃@CM could effectively induce apoptosis-related death in prostate cancer cells. In vivo antitumor results demonstrated that DOX/MSN@CaCO₃@CM administration could remarkably suppress the tumor growth. Compared with other tedious approaches to optimize the therapeutic efficacy, this study provides an effective drug targeting system only using naturally biomaterials for the treatment of prostate cancer, which might have great potential in clinic usage.

Mitochondria-targeted zirconium metal-organic frameworks for enhancing the efficacy of microwave thermal therapy against tumors

Although microwave (MW) thermal therapy has been widely studied for the treatment of tumors due to its less invasiveness, recurrence of tumors is still observed because of the relatively low bioavailability of MW sensitizers. For enhancing the bioavailability of MW sensitizers, triphenyl phosphate (TPP)-conjugated and doxorubicin (DOX)-loaded porous zirconium metal-organic framework nanocubes (ZrMOF NCs) modified with polyethylene glycol (PEG), ZrMOF-PEG-TPP@DOX NCs, were prepared as a MW sensitizer with mitochondrial-targeting ability. Moreover, the mitochondria are more susceptible to heat than the tumor tissues; this leads to improved tumor cell apoptosis. The results of this study indicate that ZrMOF NCs exhibit excellent heating effects due to the increased collisions of ions in the micropores of ZrMOFs under MW irradiation. In addition, ZrMOF-PEG-TPP@DOX NCs show preferential aggregation in the mitochondria, confirmed by confocal microscopy images. In vivo MW thermal therapeutic efficacy of ZrMOF-PEG-TPP@DOX NCs + MW is also better without recurrence during treatment than that of ZrMOF-PEG@DOX NCs + MW at a similar thermal therapeutic temperature; this reveals that the mitochondrial-targeting strategy can enhance the MW thermal therapeutic efficacy. This study provides a new biosafe MW sensitizer with mitochondrial-targeting ability for enhancing the efficacy of MW thermal therapy against tumors.

Doxorubicin/gold nanoparticles coated with liposomes for chemo-photothermal synergetic antitumor therapy

Hybrid liposome/metal nanoparticles are promising candidate drug-carriers for therapy of various diseases due to their unique photothermal effect. In this study, self-crystallized gold nanoparticles (Au NPs) and doxorubicin (DOX) were co-encapsulated within liposomes (Au/DOX-Lips) by thin film hydration and gel separation technology. The surface plasmon resonance bands of drug-carriers were controllable in the near-infrared (NIR) zone. When the complex liposome/metallic hybrids were irradiated by NIR light, they displayed higher endocytosis efficiency following the fracture of liposomal membranes and the release of Au NPs. Then, the Au NPs penetrated further into deeper tumor tissue to accomplish photothermal treatment. The Au/DOX-Lips showed an excellent antitumor effect, whose inhibition rate for tumor cells was up to 78.28%. In experiments on mice bearing tumors, the Au/DOX-Lips treated mice exhibited superior tumor suppression. This novel drug system provides huge potential for biomedical application.

Magnesium-Stabilized Multifunctional DNA Nanoparticles for Tumor-Targeted and pH-Responsive Drug Delivery

Functional nucleic acids, which can target cancer cells and realize stimuli-responsive drug delivery in tumor microenvironment, have been widely applied for anticancer chemotherapy. At present, high cost, unsatisfactory biostability, and complicated fabrication process are the main limits for the development of DNA-based drug-delivery nanocarriers. Here, a doxorubicin (Dox)-delivery nanoparticle for tumor-targeting chemotherapy is developed taking advantage of rolling circle amplification (RCA) technique, by which a high quantity of functional DNAs can be efficiently collected. Furthermore, Mg²⁺, a major electrolyte in human body showing superior biocompatibility, can sufficiently condense the very long sequence of an RCA product and better preserve its functions. The resultant DNA nanoparticle exhibits a high biostability, making it a safe and ideal nanomaterial for in vivo application. Through cellular and in vivo experiments, we thoroughly demonstrate that this kind of Mg²⁺-stabilized multifunctional DNA nanoparticles can successfully realize tumor-targeted Dox delivery. Overall, exploiting RCA technique and Mg²⁺ condensation, this new strategy can fabricate nanoparticles with a nontoxic composition through a simple fabrication process and provides a good way to preserve and promote DNA functions, which will show a broad application potential in the biomedical field.

A new strategy for hydrophobic drug delivery using a hydrophilic polymer equipped with stacking units

A highly hydrophilic polymer was used to deliver aromatic ring-containing hydrophobic agent doxorubicin (DOX) via π–π interaction.

A Triphenylphosphonium-Functionalized Mitochondriotropic Nanocarrier for Efficient Co-Delivery of Doxorubicin and Chloroquine and Enhanced Antineoplastic Activity

Drug delivery systems that target subcellular organelles and, in particular, mitochondria are considered to have great potential in treating disorders that are associated with mitochondrial dysfunction, including cancer or neurodegenerative diseases. To this end, a novel hyperbranched mitochondriotropic nanocarrier was developed for the efficient co-delivery of two different (both in chemical and pharmacological terms) bioactive compounds. The carrier is based on hyperbranched poly(ethyleneimine) functionalized with triphenylphosphonium groups that forms ~100 nm diameter nanoparticles in aqueous media and can encapsulate doxorubicin (DOX), a well-known anti-cancer drug, and chloroquine (CQ), a known chemosensitizer with arising potential in anticancer medication. The anticancer activity of this system against two aggressive DOX-resistant human prostate adenocarcinoma cell lines and in in vivo animal studies was assessed. The co-administration of encapsulated DOX and CQ leads to improved cell proliferation inhibition at extremely low DOX concentrations (0.25 μΜ). In vivo experiments against DU145 human prostate cancer cells grafted on immunodeficient mice resulted in tumor growth arrest during the three-week administration period and no pervasive side effects. The findings put forward the potential of such targeted low dose combination treatments as a therapeutic scheme with minimal adverse effects.

A metal-organic framework based nanocomposite with co-encapsulation of Pd@Au nanoparticles and doxorubicin for pH- and NIR-triggered synergistic chemo-photothermal treatment of cancer cells

Here, we report a novel metal-organic framework-based nanocomposite with encapsulated Pd@Au nanoparticles and doxorubicin (DOX) for pH- and NIR-triggered synergistic chemo-photothermal treatment of cancer cells. In this work, Pd nanoparticles, which have uniform size and dispersibility, were first synthesized and used as a template to direct the covering of Au nanosheets. The obtained Au coated Pd (Pd@Au) nanoparticles have excellent dispersibility and photothermal conversion ability, which makes them a good photothermal nanomaterial. Subsequently, an acid-degradable metal-organic framework of ZIF-8 was employed to synchronously encapsulate Pd@Au nanoparticles and DOX to get a metal-organic framework-based nanocomposite (DOX/Pd@Au@ZIF-8). Under acid conditions (e.g. pH ∼5.0 in a lysosome), the ZIF-8 framework of the DOX/Pd@Au@ZIF-8 nanocomposite could be degraded, resulting in the release of encapsulated DOX. Moreover, the present Pd@Au nanoparticles can effectively convert NIR laser light (780 nm, 2.1 W cm^-2) into heat, not only further promoting the release of DOX, but also realizing the synergistic chemo-photothermal treatment of cancer cells. The in vitro experiments showed that this nanocomposite system has an excellent synergistic treatment effect on SMMC-7721 cells, even at low concentrations (e.g. 20 μg mL^-1). With the properties of synergistic chemo-photothermal treatment, we hope that such a nanocomposite system of DOX/Pd@Au@ZIF-8 could open the door to designing a significant multifunctional system for diverse applications in cancer treatment.