pH-responsive hollow Fe-gallic acid coordination polymer for multimodal synergistic-therapy and MRI of cancer

Gallic acid-loaded HFZIF-8 for tumor-targeted delivery and thermal-catalytic therapy

"Transition" metal-coordinated plant polyphenols are a type of promising antitumor nanodrugs owing to their high biosafety and catalytic therapy potency; however, the major obstacle restricting their clinical application is their poor tumor accumulation. Herein, Fe-doped ZIF-8 was tailored using tannic acid (TA) into a hollow mesoporous nanocarrier for gallic acid (GA) loading. After hyaluronic acid (HA) modification, the developed nanosystem of HFZIF-8/GA@HA was used for the targeted delivery of Fe ions and GA, thereby intratumorally achieving the synthesis of an Fe-GA coordinated complex. The TA-etching strategy facilitated the development of a cavitary structure and abundant coordination sites of ZIF-8, thus ensuring an ideal loading efficacy of GA (23.4 wt%). When HFZIF-8/GA@HA accumulates in the tumor microenvironment (TME), the framework is broken due to the competitive protonation ability of overexpressed protons in the TME. Interestingly, the intratumoral degradation of HFZIF-8/GA@HA provides the opportunity for the in situ "meeting" of GA and Fe ions, and through the coordination of polyhydroxyls assisted by conjugated electrons on the benzene ring, highly stable Fe-GA nanochelates are formed. Significantly, owing to the electron delocalization effect of GA, intratumorally coordinated Fe-GA could efficiently absorb second near-infrared (NIR-II, 1064 nm) laser irradiation and transfer it into thermal energy with a conversion efficiency of 36.7%. The photothermal performance could speed up the Fenton reaction rate of Fe-GA with endogenous H2O2 for generating more hydroxyl radicals, thus realizing thermally enhanced chemodynamic therapy. Overall, our research findings demonstrate that HFZIF-8/GA@HA has potential as a safe and efficient anticancer nanodrug.

Bovine serum albumin-based and dual-responsive targeted hollow mesoporous silica nanoparticles for breast cancer therapy

Combination therapy is an effective way to alleviate the shortcoming of monotherapy and enhances therapeutic efficacy. Herein, a distinctive hollow mesoporous silica nanoparticle (HMSNs) encapsulated with folic acid-modified bovine serum albumin (BSA-FA), denoted as HBF, was engineered for tumor targeting and dual-responsive release of loaded-therapeutic agents MD (methylene blue (MB) and doxorubicin (DOX)). The BSA molecule as a ''gatekeeper'' prevents premature drug leakage and actively unloads the cargos through BSA detachment in response to intracellular glutathione (GSH). Folic acid (FA) promotes the specific intracellular delivery of the drug to folate receptor (FR)-expressing cancer cells to improve the efficacy of chemo-photodynamic therapy (PDT). In vitro drug release profiles showed that the drug carrier could achieve pH/redox-responsive drug release from MD@HBF owing to the cleavage of the imine bonds between HMSNs-CHO and BSA-FA and BSA intramolecular disulfide bond. Additionally, a series of biological evaluations, such as cell uptake experiments, toxicity experiments, and in vivo therapeutic assays indicated that MD@HBF possesses the features of accurately targeting FR-expressing 4T1 cells to induce cells apoptosis in vitro, exhibits outstanding tumor cell synergistic killing efficiency of chemo-photodynamic therapy (combination index CI = 0.325), and inhibits tumors growth. These results demonstrated that the strategy of combining HMSNs with stimuli-responsive biodegradable protein molecules could provide a new potential direction toward the ''on-demand'' drug release for precision chemo-photodynamic therapy in cancer treatment.

Enhanced mild-temperature photothermal therapy by pyroptosis-boosted ATP deprivation with biodegradable nanoformulation

BACKGROUND

Mild-temperature photothermal therapy (mild PTT) is a safe and promising tumor therapeutic modality by alleviating the damage of healthy tissues around the tumor due to high temperature. However, its therapeutic efficiency is easily restricted by heat shock proteins (HSPs). Thus, exploitation of innovative approaches of inhibiting HSPs to enhance mild PTT efficiency is crucial for the clinical application of PTT.

RESULTS

Herein, an innovative strategy is reported: pyroptosis-boosted mild PTT based on a Mn-gallate nanoformulation. The nanoformulation was constructed via the coordination of gallic acid (GA) and Mn²⁺. It shows an acid-activated degradation and releases the Mn²⁺ and GA for up-regulation of reactive oxygen species (ROS), mitochondrial dysfunction and pyroptosis, which can result in cellular ATP deprivation via both the inhibiton of ATP generation and incresed ATP efflux. The reduction of ATP and accumulation of ROS provide a powerful approach for inhibiting the expression of HSPs, which enables the nanoformulation-mediated mild PTT.

CONCLUSIONS

Our in-vitro and in-vivo results demonstrate that this strategy of pyroptosis-assited PTT can achieve efficient mild PTT efficiency for osteosarcoma therapy.

Metal-polyphenol polymer modified polydopamine for chemo-photothermal therapy

Chemotherapy combined with photothermal therapy (PTT) is a new way to improve the curative effect of cancer treatment. Here, we developed a multifunctional nanoparticle, namely PTX@mPDA@Fe-GA with the loading of a chemotherapeutic drug paclitaxel (PTX) for targeted and synergistic chemotherapy/photothermal therapy in lung cancer. Fe-gallic acid (Fe-GA) was coated on the surface of mesoporous polydopamine (mPDA) nanoparticles, and then the PTX was placed in the mesopores. The drug release of the loaded PTX exhibited pH- and thermal-dual responsive manner. Both mPDA and Fe-GA have high photothermal conversion ability and play a role in photothermal therapy. In addition, the results revealed that mPDA@Fe-GA had excellent biocompatibility and low hemolysis rate. The PTX-loaded mPDA@Fe-GA not only has excellent killing effect on lung cancer cells (A549) in vitro, but also can significantly suppress the growth of A549 subcutaneous tumor in nude mice. In a nutshell, the developed multifunctional nanoparticles integrate photothermal therapy and efficient chemotherapeutic drug delivery, providing new therapeutic ideas in the fight against lung cancer.

Design of Nanoparticles in Cancer Therapy Based on Tumor Microenvironment Properties

Cancer is one of the leading causes of death worldwide, and battling cancer has always been a challenging subject in medical sciences. All over the world, scientists from different fields of study try to gain a deeper knowledge about the biology and roots of cancer and, consequently, provide better strategies to fight against it. During the past few decades, nanoparticles (NPs) have attracted much attention for the delivery of therapeutic and diagnostic agents with high efficiency and reduced side effects in cancer treatment. Targeted and stimuli-sensitive nanoparticles have been widely studied for cancer therapy in recent years, and many more studies are ongoing. This review aims to provide a broad view of different nanoparticle systems with characteristics that allow them to target diverse properties of the tumor microenvironment (TME) from nanoparticles that can be activated and release their cargo due to the specific characteristics of the TME (such as low pH, redox, and hypoxia) to nanoparticles that can target different cellular and molecular targets of the present cell and molecules in the TME.

Degradable Self-Destructive Redox-Responsive System Based on Mesoporous Organosilica Nano-Vehicles for Smart Delivery of Fungicide

The development of stimuli-responsive controlled release formulations is a potential method of improving pesticide utilization efficiency and alleviating current pesticide-related environmental pollution. In this study, a self-destruction redox-responsive pesticide delivery system using biodegradable disulfide-bond-bridged mesoporous organosilica (DMON) nanoparticles as the porous carriers and coordination complexes of gallic acid (GA) and Fe(III) ions as the capping agents were established for controlling prochloraz (PRO) release. The GA-Fe(III) complexes deposited onto the surface of DMON nanoparticles could effectively improve the light stability of prochloraz. Due to the decomposition of GA-Fe(III) complexes, the nano-vehicles had excellent redox-responsive performance under the reducing environments generated by the fungus. The spreadability of PRO@DMON-GA-Fe(III) nanoparticles on the rice leaves was increased due to the hydrogen bonds between GA and rice leaves. Compared with prochloraz emulsifiable concentrate, PRO@DMON-GA-Fe(III) nanoparticles showed better fungicidal activity against Magnaporthe oryzae with a longer duration under the same concentration of prochloraz. More importantly, DMON-GA-Fe(III) nanocarriers did not observe obvious toxicity to the growth of rice seedlings. Considering non-toxic organic solvents and excellent antifungal activity, redox-responsive pesticide controlled release systems with self-destruction properties have great application prospects in the field of plant disease management.

Polyoxometalate-based nanocomposites for antitumor and antibacterial applications

Polyoxometalates (POMs), as emerging inorganic metal oxides, have been shown to have significant biological activity and great medicinal value. Nowadays, biologically active POM-based organic-inorganic hybrid materials have become the next generation of antibacterial and anticancer drugs because of their customizable molecular structures related to their highly enhanced antitumor activity and reduced toxicity to healthy cells. In this review, the current developed strategies with POM-based materials for the purpose of antibacterial and anticancer activities from different action principles inducing cell death and hyperpolarization, cell plasma membrane destruction, interference with bacterial respiratory chain and inhibiting bacterial growth are overviewed. Moreover, specific interactions between POM-based materials and biomolecules are highlighted for a better understanding of their antibacterial and anticancer mechanisms. POMs have great promise as next-generation antibacterial and anticancer drugs, and this review will provide a valuable systematic reference for the further development of POM-based nanomaterials.

Iron-Based Hollow Nanoplatforms for Cancer Imaging and Theranostics

Over the past decade, iron (Fe)-based hollow nanoplatforms (Fe-HNPs) have attracted increasing attention for cancer theranostics, due to their high safety and superior diagnostic/therapeutic features. Specifically, Fe-involved components can serve as magnetic resonance imaging (MRI) contrast agents (CAs) and Fenton-like/photothermal/magnetic hyperthermia (MTH) therapy agents, while the cavities are able to load various small molecules (e.g., fluorescent dyes, chemotherapeutic drugs, photosensitizers, etc.) to allow multifunctional all-in-one theranostics. In this review, the recent advances of Fe-HNPs for cancer imaging and treatment are summarized. Firstly, the use of Fe-HNPs in single T₁-weighted MRI and T₂-weighted MRI, T₁-/T₂-weighted dual-modal MRI as well as other dual-modal imaging modalities are presented. Secondly, diverse Fe-HNPs, including hollow iron oxide (IO) nanoparticles (NPs), hollow matrix-supported IO NPs, hollow Fe-complex NPs and hollow Prussian blue (PB) NPs are described for MRI-guided therapies. Lastly, the potential clinical obstacles and implications for future research of these hollow Fe-based nanotheranostics are discussed.

Stable bifunctional ZnII-based sensor toward acetylacetone and L-histidine by fluorescence red shift and turn-on effect

A new coordination polymer [Zn(bbip)(NH2-BDC)]n (JXUST-15, bbip = 2,6-bis(benzimidazol-1-yl)pyridine and NH2-H2BDC = 2-aminoterephthalic acid) has been synthesized by mixed ligand strategy. The structure analysis shows that JXUST-15 takes a two-dimensional...