Nanoscale Coordination Polymers Codeliver Carboplatin and Gemcitabine for Highly Effective Treatment of Platinum-Resistant Ovarian Cancer

Combination of micelles and liposomes as a promising drug delivery system: a review

Among various nanocarriers, liposomes, and micelles are relatively mature drug delivery systems with the advantages of prolonging drug half-life, reducing toxicity, and improving efficacy. However, both have problems, such as poor stability and insufficient targeting. To further exploit the excellent properties of micelles and liposomes and avoid their shortcomings, researchers have developed new drug delivery systems by combining the two and making use of their respective advantages to achieve the goals of increasing the drug loading capacity, multiple targeting, and multiple drug delivery. The results have demonstrated that this new combination approach is a very promising delivery platform. In this paper, we review the combination strategies, preparation methods, and applications of micelles and liposomes to introduce the research progress, advantages, and challenges of composite carriers.

Platinum-based combination nanomedicines for cancer therapy

The relatively low success rate of cancer nanomedicines has raised debate on the roles of the enhanced permeability and retention (EPR) effect in enhancing drug delivery to tumors and improving therapeutic efficacy. In this review, we highlight new strategies beyond the EPR effect for enhancing nanoparticle delivery to tumors. We discuss the roles of transcellular extravasation, receptor-mediated pathways, and protein corona interactions on nanoparticle deposition in tumors. We summarize recent progress in platinum-based combination nanomedicines containing multiple chemotherapeutics with synergistic anticancer mechanisms and multiple anticancer therapies with novel mechanisms to enhance drug delivery and antitumor activities. We also highlight future opportunities in platinum-based combination nanomedicines and key hurdles for the translation of these combination nanomedicines into the clinic.

Pharmacological ascorbate potentiates combination nanomedicines and reduces cancer cell stemness to prevent post-surgery recurrence and systemic metastasis

Conventional chemotherapy targets proliferative cancer cells to halt tumor progression or regress tumors. However, the plasticity of tumor cells enables their phenotypical changes to acquire chemo-resistance, leading to treatment failure or tumor recurrence after a successful treatment course. Here, we report the use of high-dose pharmacologic ascorbate to potentiate treatment efficacy of nanoscale coordination polymers (NCPs) delivering two clinical combinations of chemotherapeutics, carboplatin/docetaxel and oxaliplatin/SN38, and to target metabolic plasticity of tumor cells. Combination treatments of high-dose ascorbate and NCPs overcome multi-drug resistance by significantly reducing the abundance of cancer stem cells (CSCs) in solid tumors, as evidenced by reduced expression of tumor pluripotency factors. The clearance of CSCs inhibits post-surgery recurrence and systemic metastasis in multiple mouse models of cancer.

Dual-Drug Conjugated Glyco-Nanoassemblies for Tumor-Triggered Targeting and Synergistic Cancer Therapy

Drug-conjugated nanoassemblies potentiate the efficiency of anticancer drugs through the advantages of high drug-loading capacity and passive/active targeting ability in cancer therapy. This study describes the synthesis of gemcitabine (Gem) and cisplatin (cisPt) dual-drug-functionalized glyco-nanoassemblies (GNs) for anticancer drug delivery systems. It also investigates the pH-triggered drug delivery of the conventional anticancer drug cisPt. A Gem-functionalized well-defined glycoblock copolymer backbone (P(iprFruMA-b-MAc)-Gem), which consists of fructose and methacrylic acid segments, was synthesized via a reversible addition-fragmentation chain transfer (RAFT) polymerization method. Following the hydrolysis of the protecting groups on the backbone copolymer, cisPt functionalization of P(FruMA-b-MAc)-Gem in aqueous media was carried out during the transformation of glycoblock polymers into self-assembled spherical glyco-nanoassemblies (GN3). Monodrug-functionalized glyco-nanoassemblies were also prepared either with Gem (GN1) or cisPt (GN2) to compare the synergetic effect of dual-drug conjugated glyco-nanoassemblies (GN3). The sizes of glyco-nanoassemblies GN1, GN2, and GN3 were found as 5.76 ± 0.64, 59.80 ± 0.13, and 53.80 ± 3.90 nm and dispersity (Đ) values as 0.476, 0.292, and 0.311 by dynamic light scattering (DLS) measurement, respectively. The in vitro studies revealed that the drug-free glyco-nanoassemblies are biocompatible at concentrations higher than 296 μg/mL. The drug-conjugated glyco-nanoassemblies (GN1 and GN2) exhibited in vitro cytotoxicity against human breast cancer cell lines of MDA-MB-231 comparable to free Gem and cisPt, illustrating an efficient drug release into the tumor environment. Additionally, GNs exhibited higher selectivity and preferential cellular internalization in MDA-MB-231 when compared to healthy cell lines of CCD-1079Sk. These dual-drug conjugated GNs can effectively enhance the killing of cancer cells and increase synergistic chemotherapy.

Nanocarriers containing platinum compounds for combination chemotherapy

Platinum compounds-based drugs are used widely in the clinic for the treatment of many types of cancer. However, serious undesirable side effects and intrinsic or acquired resistance limit their successful clinic use. Nanocarrier-based combination chemotherapy is considered to be an effective strategy to resolve these challenges. This review introduces the recent advance in nanocarriers containing platinum compounds for combination cancer chemotherapy, including liposomes, polymer nanoparticles, polymer micelles, mesoporous silica nanoparticles, carbon nanohors, polymer-caged nanobins, carbon nanotube, nanostructured lipid carriers, solid lipid nanoparticles, and multilayered fiber mats in detail.

One Stone Two Birds: Redox-Sensitive Colocalized Delivery of Cisplatin and Nitric Oxide through Cascade Reactions

Bio-orthogonal bond-cleavage reactions have been used in cancer therapy for improving the biological specificity of prodrug activation, but the spatiotemporal consistency of reactants is still a huge challenge. Although, in most cases, the cleavage catalysts and caged prodrugs are administrated separately, it is difficult to avoid the reactions in advance before they meet at the tumor site. Herein, we design and construct novel coordinative nanoparticles, integrating two prodrugs A and B as ligands and ferric ions as coordinative centers. After nanoparticles accumulated in tumor through passive targeting, inert Pt(IV) prodrug A is specifically and spontaneously reduced into active Pt(II) cisplatin, which acts as the cleavage catalyst to subsequently initiate the in situ bio-orthogonal depropargylation of B, that is, O ²-propargyl nitric oxide (NO) donor. The unique structure of coordinative nanoparticles ensures the spatiotemporal consistency of reactants (prodrugs A and B) and products (cytotoxic cisplatin and tumoricidal NO) for the bio-orthogonal bond-cleavage reaction, which leads to an improved synergistic therapeutic activity for triple-negative breast cancer (TNBC). This new concept of bio-orthogonal dual-prodrug coordinative nanoparticles may inspire further applications in bio-orthogonal chemistry and drug delivery for combination chemotherapy.

CuS Nanoparticles-Loaded and Cisplatin Prodrug Conjugated Fe(III)-MOFs for MRI-Guided Combination of Chemotherapy and NIR-II Photothermal Therapy

Ovarian cancer has become an urgent threat to global female healthcare. Cisplatin, as the traditional chemotherapeutic agent against ovarian cancer, retains several limitations, such as drug resistance and dose-limiting toxicity. In order to solve the above problems and promote the therapeutic effect of chemotherapy, combining chemotherapy and phototherapy has aroused wide interest. In this study, we constructed a versatile cisplatin prodrug-conjugated therapeutic platform based on ultrasmall CuS-modified Fe(III)-metal-organic frameworks (MIL-88) (named M-Pt/PEG-CuS) for tumor-specific enhanced synergistic chemo-/phototherapy. After intravenous injection, M-Pt/PEG-CuS presented obvious accumulation in tumor and Fe(III)-MOFs possessed magnetic resonance imaging (MRI) to guide synergy therapy. Both in vitro and in vivo experimental results showed that M-Pt/PEG-CuS could not only successfully inhibit tumor growth by combining chemotherapy and NIR-II PTT but also avoid the generation of liver damage by the direct treatment of cisplatin(II). Our work presented the development of the nanoplatform as a novel NIR-II photothermal agent, as well as gave a unique combined chemo-photothermal therapy strategy, which might provide new ways of ovarian cancer therapy for clinical translation.

Daidzin inhibits hepatocellular carcinoma survival by interfering with the glycolytic/gluconeogenic pathway through downregulation of TPI1

Daidzin (DDZ) is a natural brassin-like compound extracted from the soybean, and has been found to have therapeutic potential against tumors in recent years. This study investigates the therapeutic effect of DDZ on hepatocellular carcinoma cells and elucidates the possible mechanisms of action. The viability of HCCLM3 and Hep3B cells was detected by MTT assay. Western blots and qPCR were used to detect the protein and mRNA levels of proliferation and apoptosis related genes. Gas chromatography-mass spectrometry (GC-MS) was used for metabolome analysis. In vivo antitumor effects were assessed in nude mice engrafted with HCC cell lines. Our results show that DDZ treatment dose-dependently inhibited cell viability, migration, and survival. The expressions of CDK1, BCL2, MYC, and survivin were reduced, while the expressions of BAX and PARP were increased in DDZ treated cells. The differentially expressed metabolites detected in DDZ treated cultures are associated with glycolysis/gluconeogenesis pathways. Bioinformatic analysis identified TPI1, a gene in the glycolysis pathway with prognostic value for hepatocellular carcinoma (HCC), and DDZ treatment downregulated this gene. In vivo experiments show that DDZ significantly reduced the tumor volume and weight, and inhibited Ki67 expression within tumors. This study shows that DDZ interfered with the survival and migration of hepatocellular carcinoma cells, likely via TPI1 and the gluconeogenesis pathway.

Nanoscale Coordination Polymers for Combined Chemotherapy and Photodynamic Therapy of Metastatic Cancer

Combination therapy enhances anticancer efficacy through synergistic effects of different drugs/modalities and can potentially address the challenges in the treatment of metastatic diseases. Here we report the design of carb/pyro nanoscale coordination polymer nanoparticles that carry carboplatin (carb) in the core and the photosensitizer pyrolipid (pyro) on the shell for the treatment of metastatic triple negative breast cancer. Upon light irradiation, carb/pyro generated reactive oxygen species to cause severe cell apoptosis and early calreticulin exposure. Upon intravenous injection and local light irradiation, carb/pyro significantly regressed tumor growth in the 4T1 murine metastatic breast cancer model. When combined with an anti-CD47 antibody, carb/pyro with light irradiation completely eradicated primary and metastatic 4T1 tumors in 50% mice. The anticancer efficacy of carb/pyro was also demonstrated in the CT26 murine colorectal cancer model.

Prodrug-based nano-delivery strategy to improve the antitumor ability of carboplatin in vivo and in vitro

Chemotherapy plays a major role in the treatment of cancer, but it still has great limitations in anti-tumor effect. Carboplatin (CAR) is the first-line drug in the treatment of non-small cell lung cancer, but the therapeutic effect is demonstrated weak. Therefore, we modified CAR with hexadecyl chain and polyethylene glycol, so as to realize its liposolubility and PEGylation. The synthesized amphiphilic CAR prodrugs could self-assemble into polymer micelles in water with an average particle size about 11.8 nm and low critical micelles concentration (0.0538 mg·mL^-1). In vivo pharmacodynamics and cytotoxicity experiment evidenced that the polymer micelles were equipped with preferable anti-tumor effect, finally attained the aim of elevating anti-tumor effect and prolonging retention time in vivo. The self-assembled micelles skillfully solve the shortcomings of weak efficacy of CAR, which provides a powerful platform for the application of chemical drug in oncology.

Micelle-contained and PEGylated hybrid liposomes of combined gemcitabine and cisplatin delivery for enhancing antitumor activity

Combination, synergistic chemotherapy with gemcitabine (GEM) and cisplatin (CDDP) is a common strategy, and has been recommended for tumor treatment due to its promoted therapeutic effect and reduced systemic toxicity. However, this process involves the intravenous infusion of GEM prior to that of CDDP, which is inconvenient for patients and staff. Here, a novel hybrid nano-carrier system comprised of micelles encapsulated within PEGylated liposomes is proposed, in order to combine the unique strengths of each component. CDDP was bonded with PLG-PEG, and then the formed CDDP@PLG-PEG micelles and GEM were co-loaded inside PEGylated liposomes. The hybrid liposomes with the optimized GEM/CDDP ratio (1:0.6) showed a roughly spherical morphology, appropriate drug loading, and sustained release behavior. In vitro, the hybrid liposomes had 1.72-fold increased cellular uptake, and 57.42%-fold decreased IC₅₀ value. In vivo, pharmacokinetic studies showed increased t_1/2 values (125.64%- and 128.57%-folds for GEM and CDDP), decreased clearance (41.90%- and 2.37%-folds), and promoted AUC (262.76%- and 4577.24%-folds). Finally, an in vivo antitumor study showed effective activity in regards to lung tumor size and weight, which were 40.48%- and 33.11%-folds that of GEM/CDDP solution. In summary, we demonstrated the development of an effective micelle-containing PEGylated hybrid liposomes for combined GEM/CDDP delivery.

Polymeric Nanoparticle Delivery of Combination Therapy with Synergistic Effects in Ovarian Cancer

Treatment of ovarian cancer is challenging due to late stage diagnosis, acquired drug resistance mechanisms, and systemic toxicity of chemotherapeutic agents. Combination chemotherapy has the potential to enhance treatment efficacy by activation of multiple downstream pathways to overcome drug resistance and reducing required dosages. Sequence of delivery and the dosing schedule can further enhance treatment efficacy. Formulation of drug combinations into nanoparticles can further enhance treatment efficacy. Due to their versatility, polymer-based nanoparticles are an especially promising tool for clinical translation of combination therapies with tunable dosing schedules. We review polymer nanoparticle (e.g., micelles, dendrimers, and lipid nanoparticles) carriers of drug combinations formulated to treat ovarian cancer. In particular, the focus on this review is combinations of platinum and taxane agents (commonly used first line treatments for ovarian cancer) combined with other small molecule therapeutic agents. In vitro and in vivo drug potency are discussed with a focus on quantifiable synergistic effects. The effect of drug sequence and dosing schedule is examined. Computational approaches as a tool to predict synergistic drug combinations and dosing schedules as a tool for future nanoparticle design are also briefly discussed.

Point-source burst of coordination polymer nanoparticles for tri-modality cancer therapy

Cancer immunotherapy, particularly the inhibition of immune checkpoints with neutralizing antibodies, has revolutionized the treatment of some cancer patients. However, immune checkpoint blockade has not provided survival benefits to most patients with colorectal and ovarian cancers. This work reports the design of acid-sensitive core-shell nanoscale coordination polymer particles (NCP) comprising a carboplatin prodrug and an siRNA against PD-L1 (siPD-L1) in the core and digitoxin on the shell for tri-modality cancer therapy. Upon cellular uptake, NCP particles rapidly burst in acidic organelles to release carboplatin for apoptosis, digitoxin for inducing immunogenicity, and siPD-L1 for PD-L1 knockdown. With long blood circulation and high tumor accumulation, NCP particles efficiently suppress the growth and metastasis of syngeneic cancers through reactivating innate and adaptive immune responses. NCP particles thus provide a promising platform to synergistically combine chemotherapy and immunotherapy for the treatment of advanced and aggressive cancers.

A novel biocompatible formate bridged 1D-Cu(ii) coordination polymer induces apoptosis selectively in human lung adenocarcinoma (A549) cells

Copper compounds are promising candidates for next-generation metal anticancer drugs. Therefore, we synthesized and characterized a formate bridged 1D coordination polymer [Cu(L)(HCOO)₂]_n, (L = 2-methoxy-6-methyl-3-((quinolin-8-ylimino)methyl)chroman-4-ol), PCU1, wherein the Cu(ii) center adopts a square pyramidal coordination environment with adjacent CuCu distances of 5.28 Å. Primarily, in vitro DNA interaction studies revealed a metallopolymer which possesses high DNA binding propensity and cleaves DNA via the oxidative pathway. We further analysed its potential on cancerous cells MCF-7, HeLa, A549, and two non-tumorigenic cells HEK293 and HBE. The selective cytotoxicity potential of PCU1 against A549 cells driven us to examine the mechanistic pathways comprehensively by carrying out various assays viz, cell cycle arrest, Annexin V-FTIC/PI assay, autophagy, intercellular localization, mitochondrial membrane potential 'MMP', antiproliferative assay, and gene expression of TGF-β and MMP-2.

Nanoparticle-based drug delivery systems with platinum drugs for overcoming cancer drug resistance

Platinum drugs are commonly used in cancer therapy, but their therapeutic outcomes have been significantly compromised by the drug resistance of cancer cells. To this end, intensive efforts have been made to develop nanoparticle-based drug delivery systems for platinum drugs, due to their multifunctionality in delivering drugs, in modulating the tumor microenvironment, and in integrating additional genes, proteins, and small molecules to overcome chemoresistance in cancers. To facilitate the clinical application of these promising nanoparticle-based platinum drug delivery systems, this paper summarizes the common mechanisms for chemoresistance towards platinum drugs, the advantages of nanoparticles in drug delivery, and recent strategies of nanoparticle-based platinum drug delivery. Furthermore, we discuss how to design delivery platforms more effectively to overcome chemoresistance in cancers, thereby improving the efficacy of platinum-based chemotherapy.

Revisiting chemoresistance in ovarian cancer: Mechanism, biomarkers, and precision medicine

Among the gynecological cancers, ovarian cancer is the most lethal. Its therapeutic options include a combination of chemotherapy with platinum-based compounds and cytoreductive surgery. Most ovarian cancer patients exhibit an initial response to platinum-based therapy, however, platinum resistance has led to up to 80% of this responsive cohort becoming refractory. Ovarian cancer recurrence and drug resistance to current chemotherapeutic options is a global challenge. Chemo-resistance is a complex phenomenon that involves multiple genes and signal transduction pathways. Therefore, it is important to elucidate on the underlying molecular mechanisms involved in chemo-resistance. This inform decisions regarding therapeutic management and help in the identification of novel and effective drug targets. Studies have documented the individual biomarkers of platinum-resistance in ovarian cancer that are potential therapeutic targets. This review summarizes the molecular mechanisms of platinum resistance in ovarian cancer, novel drug targets, and clinical outcomes.

Nanoparticle delivery systems to combat drug resistance in ovarian cancer

Due to the lack of early symptoms and difficulty of accurate diagnosis, ovarian cancer is the most lethal gynecological cancer faced by women. First-line therapy includes a combination of tumor resection surgery and chemotherapy regimen. However, treatment becomes more complex upon recurrence due to development of drug resistance. Drug resistance has been linked to many mechanisms, including efflux transporters, apoptosis dysregulation, autophagy, cancer stem cells, epigenetics, and the epithelial-mesenchymal transition. Thus, developing and choosing effective therapies is exceptionally complex. There is a need for increased specificity and efficacy in therapies for drug-resistant ovarian cancer, and research in targeted nanoparticle delivery systems aims to fulfill this challenge. Although recent research has focused on targeted nanoparticle-based therapies, few of these therapies have been clinically translated. In this review, non-viral nanoparticle delivery systems developed to overcome drug-resistance in ovarian cancer were analyzed, including their structural components, surface modifications, and drug-resistance targeted mechanisms.

Use of Anticancer Platinum Compounds in Combination Therapies and Challenges in Drug Delivery

As one of the leading and most important metal-based drugs, platinum-based pharmaceuticals are widely used in the treatment of solid malignancies. Despite significant side effects and acquired drug resistance have limited their clinical applications, platinum has shown strong inhibitory effects for a wide assortment of tumors. Drug delivery systems using emerging technologies such as liposomes, dendrimers, polymers, nanotubes and other nanocompositions, all show promise for the safe delivery of platinum-based compounds. Due to the specificity of nano-formulations; unwanted side-effects and drug resistance can be largely averted. In addition, combinational therapy has been shown to be an effective way to improve the efficacy of platinum based anti-tumor drugs. This review first introduces drug delivery systems used for platinum and combinational therapeutic delivery. Then we highlight some of the recent advances in the field of drug delivery for combinational therapy; specifically progress in leveraging the cytotoxic nature of platinum-based drugs, the combinational effect of other drugs with platinum, while evaluating the drug targeting, side effect reducing and sitespecific nature of nanotechnology-based delivery platforms.

Design of Targeted Nanostructured Coordination Polymers (NCPs) for Cancer Therapy

Conventional cancer chemotherapy presents notable drug side effects due to non-selective action of the chemotherapeutics to normal cells. Nanoparticles decorated with receptor-specific ligands on the surface have shown an important role in improving site-selective binding, retention, and drug delivery to the cancer cells. This review summarizes the recent reported achievements using nanostructured coordination polymers (NCPs) with active targeting properties for cancer treatment in vitro and in vivo. Despite the controversy surrounding the effectivity of active targeting nanoparticles, several studies suggest that active targeting nanoparticles notably increase the selectivity and the cytotoxic effect in tumoral cells over the conventional anticancer drugs and non-targeted nanoparticle platform, which enhances drug efficacy and safety. In most cases, the nanocarriers have been endowed with remarkable capabilities such as stimuli-responsive properties, targeting abilities, or the possibility to be monitored by imaging techniques. Unfortunately, the lack of preclinical studies impedes the evaluation of these unique and promising findings for the translation of NCPs into clinical trials.

Combination Treatment of Cervical Cancer Using Folate-Decorated, pH-Sensitive, Carboplatin and Paclitaxel Co-Loaded Lipid-Polymer Hybrid Nanoparticles

PURPOSE

Cervical cancer is one of the most common causes of death among women globally. Combinations of cisplatin, paclitaxel, bevacizumab, carboplatin, topotecan, and gemcitabine are recommended as first-line therapies.

METHODS

This study focuses on the development of folate-decorated, pH-sensitive lipid-polymer hybrid nanoparticles (LPNs). Loading carboplatin (CBP) and paclitaxel (PTX), LPNs were expected to combine the therapeutic effects of CBP and PTX, thus show synergistic ability on cervical cancer.

RESULTS

FA-CBP/PTX-LPNs showed the sizes of 169.9 ± 5.6 nm, with a narrow size distribution of 0.151 ± 0.023. FA-CBP/PTX-LPNs exhibited pH-responsive drug release, high cellular uptake efficiency (66.7 ± 3.1%), and prominent cell inhibition capacity (23 ± 1.1%). In vivo tumor distribution and tumor inhibition efficiency of FA-CBP/PTX-LPNs was the highest, with no obvious body weight lost.

CONCLUSION

High tumor distribution and remarkable antitumor efficiency obtained using in vitro as well as in vivo models further proved the FA-CBP/PTX-LPNs is a promising tool for cervical cancer therapy.

Recent advances in metallopolymer-based drug delivery systems

Metallopolymers (MPs) or metal-containing polymers have shown great potential as new drug delivery systems (DDSs) due to their unique properties, including universal architectures, composition, properties and surface chemistry. Over the past few decades, the exponential growth of many new classes of MPs that deal with these issues has been demonstrated. This review presents and assesses the recent advances and challenges associated with using MPs as DDSs. Among the most widely used MPs for these purposes, metal complexes based on synthetic and natural polymers, coordination polymers, metal-organic frameworks, and metallodendrimers are distinguished. Particular attention is paid to the stimulus- and multistimuli-responsive metallopolymer-based DDSs. Of considerable interest is the use of MPs for combination therapy and multimodal systems. Finally, the problems and future prospects of using metallopolymer-based DDSs are outlined. The bibliography includes articles published over the past five years.

Systemic miRNA delivery by nontoxic nanoscale coordination polymers limits epithelial-to-mesenchymal transition and suppresses liver metastases of colorectal cancer

Though early detection and treatment of primary tumors has significantly improved in recent years, metastatic disease remains among the most significant challenges in cancer therapy. Cancer cells can disseminate before the primary tumor is detected to form micro or gross metastases, requiring toxic systemic therapies. To prevent and suppress metastases, we have developed a nontoxic, long-circulating nanoscale coordination polymer (NCP) protecting microRNA (miRNA) in circulation and releasing it in tumors. PtIV(en)2 [en = ethylenediamine] containing NCPs (PtEN) can release a nontoxic, kinetically inert PtII(en)2 compound and carbon dioxide which aids the endosomal escape of its miRNA cargo, miR-655-3p. Without the presence of the PtEN core, the miRNA showed cellular uptake but no effect. When transfected into human colorectal HCT116 cells by NCPs, this oligometastatic miRNA limited proliferation and epithelial-to-mesenchymal transition by preventing β-catenin nuclear translocation and tumor cell invasion. Systemic administrations of PtEN/miR-655-3p sustained effective transfection to reduce liver colonization and tumor burden in a xenogenic hepatic metastatic model of HCT116 without any observable toxicity.

Light-harvesting metal-organic framework nanoprobes for ratiometric fluorescence energy transfer-based determination of pH values and temperature

Light-harvesting nanoprobes were developed by self-assembly of nanoscale metal-organic frameworks (NMOFs) and stimuli-responsive polymers for fluorometric sensing of pH values and temperature. Two kinds of fluorescent NMOFs (acting as the energy donor) and stimuli-responsive polymers conjugated to fluorophores (acting as energy acceptors) were prepared and characterized. The NMOFs include zirconium(IV) and π-conjugated dicarboxylate ligands. The fluorophores inclued cyaine dyes and a Bodipy dye. The energy donor and energy acceptor form a Förster resonance energy transfer (FRET) nanosystem. In the light-harvesting system, the chain lengths of the stimuli-responsive polymers vary when the local pH value or temperature change. Ratiometric sensing of pH and temperature was accomplished by monitoring fluorescence. pH values were can be sensed between 3.0 and 8.0 under 420 nm excitation and by ratioing the emission peaks at 645 and 530 nm. Temperature can be sensed in the range from 25 to 50 °C under 550 nm excitation and by ratioing the emission peaks at 810 and 695 nm. The nanoprobes display excellent water dispersibility and cell membrane permeability. They were applied to image pH values and temperature in HeLa cells. Graphical abstract Schematic presentation of an effective strategy to fabricate light-harvesting nanoprobes by self-assembly of MOFs and stimuli-responsive polymers for ratiometric pH and temperature sensing. The distance as the polymer length between energy donor and acceptor is crucial for energy transfer efficiency.

Metallopolymers for advanced sustainable applications

Since the development of metallopolymers, there has been tremendous interest in the applications of this type of materials. The interest in these materials stems from their potential use in industry as catalysts, biomedical agents in healthcare, energy storage and production as well as climate change mitigation. The past two decades have clearly shown exponential growth in the development of many new classes of metallopolymers that address these issues. Today, metallopolymers are considered to be at the forefront for discovering new and sustainable heterogeneous catalysts, therapeutics for drug-resistant diseases, energy storage and photovoltaics, molecular barometers and thermometers, as well as carbon dioxide sequesters. The focus of this review is to highlight the advances in design of metallopolymers with specific sustainable applications.

Carboplatin-loaded SMNDs to reduce GSH-mediated platinum resistance for prostate cancer therapy

Glutathione (GSH)-mediated drug resistance can strongly weaken the therapeutic efficiency of platinum(ii).

Protein Mimetic and Anticancer Properties of Monocyte-Targeting Peptide Amphiphile Micelles

Monocyte chemoattractant protein-1 (MCP-1) stimulates the migration of monocytes to inflammatory sites, leading to the progression of many diseases. Recently, we described a monocyte-targeting peptide amphiphile micelle (MCP-1 PAM) incorporated with the chemokine receptor CCR2 binding motif of MCP-1, which has a high affinity for monocytes in atherosclerotic plaques. We further report here the biomimetic components of MCP-1 PAMs and the influence of the nanoparticle upon binding to monocytes. We report that MCP-1 PAMs have enhanced secondary structure compared to the MCP-1 peptide. As a result, MCP-1 PAMs displayed improved binding and chemoattractant properties to monocytes, which upregulated the inflammatory signaling pathways responsible for monocyte migration. Interestingly, when MCP-1 PAMs were incubated in the presence of prostate cancer cells in vitro, the particle displayed anticancer efficacy by reducing CCR2 expression. Given that monocytes play an important role in tumor cell migration and invasion, our results demonstrate that PAMs can improve the native biofunctional properties of the peptide and may be used as an effective inhibitor to prevent chemokine-receptor interactions that promote disease progression.

Recent advances in co-delivery systems based on polymeric nanoparticle for cancer treatment

Cancer is a broad term for a class of prevalent diseases as one in three people develop cancer during their lifetime. Although, there are few success stories of cancer therapy, most of the existing medications do not lead to complete recovery. Because of the complexity of cancer, usually a single therapeutic approach is insufficient for the suppression of cancer growth and metastasis. Simultaneous loading and co-delivery of different agents with different physiochemical characteristics to the same tumors have been suggested for minimizing the dose of anticancer drugs and achieving the synergistic therapeutic impacts in cancers treatment. Intense work to develop nanotechnology-based systems as a suitable option for cancer treatment is currently underway. The purpose of this review is to provide an overview of the co-delivery systems based on polymeric nanoparticles including polymeric micelles, dendrimers, poly-d,l-lactide-co-glycolide, polyethylenimine, poly(l-lysine) and chitosan for efficacious cancer therapy.

Nanoscale metal-organic frameworks coated with poly(vinyl alcohol) for ratiometric peroxynitrite sensing through FRET

This work describes a facile yet powerful approach to energy-transfer NMOF (nanoscale metal–organic framework) fabrication for ratiometric peroxynitrite (ONOO^–) sensing.

This work describes a facile yet powerful approach to energy-transfer NMOF (nanoscale metal–organic framework) fabrication for ratiometric peroxynitrite (ONOO^–) sensing. Poly(vinyl alcohol) (PVA) is chosen to organize the energy donor (NMOF) and acceptor (molecular probes). PVA can conveniently graft onto the NMOF surface and bind to the molecular probes bearing the arylboronic acid group through multiple weak coordination interactions. Due to efficient Förster resonance energy transfer (FRET), the bright blue fluorescence of the NMOF is quenched while the green or red emission from the acceptor is enhanced. Upon reacting with ONOO^–, the ONOO^– sensors depart from the NMOF and the FRET is interrupted and the fluorescence of the NMOF recovered. Based on this strategy, we developed two ratiometric ONOO^– nanosensors for the detection of ONOO^– in solutions and living cells. This work is the first report of NMOF ONOO^– sensors through FRET and could inspire the design of other NMOF based chemical sensors and biosensors.