Mn(II) mediated degradation of artemisinin based on Fe3O4@MnSiO3-FA nanospheres for cancer therapy in vivo

Recent development of pH-responsive theranostic nanoplatforms for magnetic resonance imaging-guided cancer therapy

The acidic characteristic of the tumor site is one of the most well-known features and provides a series of opportunities for cancer-specific theranostic strategies. In this regard, pH-responsive theranostic nanoplatforms that integrate diagnostic and therapeutic capabilities are highly developed. The fluidity of the tumor microenvironment (TME), with its temporal and spatial heterogeneities, makes noninvasive molecular magnetic resonance imaging (MRI) technology very desirable for imaging TME constituents and developing MRI-guided theranostic nanoplatforms for tumor-specific treatments. Therefore, various MRI-based theranostic strategies which employ assorted therapeutic modes have been drawn up for more efficient cancer therapy through the raised local concentration of therapeutic agents in pathological tissues. In this review, we summarize the pH-responsive mechanisms of organic components (including polymers, biological molecules, and organosilicas) as well as inorganic components (including metal coordination compounds, metal oxides, and metal salts) of theranostic nanoplatforms. Furthermore, we review the designs and applications of pH-responsive theranostic nanoplatforms for the diagnosis and treatment of cancer. In addition, the challenges and prospects in developing theranostic nanoplatforms with pH-responsiveness for cancer diagnosis and therapy are discussed.

Acidity-Triggered Charge-Convertible Conjugated Polymer for Dihydroartemisinin Delivery and Tumor-Specific Chemo-Photothermal Therapy

Since the nonspecificity and nonselectivity of traditional treatment models lead to the difficulty of cancer treatment, nanobased strategies are needed to fill in the gaps of current approaches. Herein, a tumor microenvironment (TME)-responsive chemo-photothermal treatment model was developed based on dihydroartemisinin (DHA)-loaded conjugated polymers (DHA@PLGA-PANI). The synthesized DHA@PLGA-PANI exhibited enhanced photothermal properties under mild-acidic conditions and thus triggered local heat at the tumor site. Meanwhile, these iron-doped conjugated polymers of PLGA-PANI were used as the source of Fe, and benefiting from the Fe-dependent cytotoxicity of DHA, the burst of free radicals could be generated in tumors. Therefore, the combination of TME-responsive chemo-photothermal therapy could achieve effective tumor efficacy.

Thermosensitive nanocomposite components for combined photothermal-photodynamic therapy in liver cancer treatment

Phototherapies, in the form of photodynamic therapy (PDT) and photothermal therapy (PTT), have great application prospects in the field of biomedical science due to high precision and non-invasiveness. Because of the limited therapeutic efficacy of single phototherapy, researchers start to focus on combined PTT-PDT. Here, we designed a composite nanomaterial for PTT-PDT. H-TiO₂ mesoporous spheres were prepared by sol-gel method and hydrogenation treatment. After modification with polydopamine (PDA), they were combined with indocyanine green (ICG) and NPe6 photosensitizers and coated by thermosensitive liposomes to prepare H-TiO₂ @PDA@ICG@NPe6 @Lipo nanocomposite component. The results indicated a substantial improvement of the component in the aspects of spectral response range, photothermal conversion efficiency and light absorption performance by modification and photosensitizers, in the absence of any toxicities on cells. Thermal induction and sequential irradiation with 808 nm and 664 nm lasers induced the aggregation of H-TiO₂ @PDA@ICG@NPe6 @Lipo at the tumor site to generate hyperthermia and massive reactive oxygen species (ROS), resulting in decreased cell activity or even cell apoptosis and restrained growth of allograft tumors. These findings underscore the favorable effects of H-TiO₂ @PDA@ICG@NPe6 @Lipo on the combined phototherapies and provide approaches for the development of nano-drugs in the context of liver cancer.

Inhalable Biomineralized Liposomes for Cyclic Ca2+-Burst-Centered Endoplasmic Reticulum Stress Enhanced Lung Cancer Ferroptosis Therapy

Lung cancer with the highest mortality poses a great threat to human health. Ferroptosis therapy has recently been raised as a promising strategy for lung cancer treatment by boosting the reactive species (ROS) production and lipid peroxidation (LPO) accumulation intracellularly. However, the insufficient intracellular ROS level and the unsatisfactory drug accumulation in lung cancer lesions hamper the efficacy of ferroptosis therapy. Here, an inhalable biomineralized liposome LDM co-loaded with dihydroartemisinin (DHA) and pH-responsive calcium phosphate (CaP) was constructed as a ferroptosis nanoinducer for achieving Ca²⁺-burst-centered endoplasmic reticulum (ER) stress enhanced lung cancer ferroptosis therapy. Equipped with excellent nebulization properties, about 6.80-fold higher lung lesions drug accumulation than intravenous injection made the proposed inhalable LDM an ideal nanoplatform for lung cancer treatment. The Fenton-like reaction mediated by DHA with peroxide bridge structure could contribute to intracellular ROS production and induce ferroptosis. Assisted by DHA-mediated sarco-/endoplasmic reticulum calcium ATPase (SERCA) inhibition, the initial Ca²⁺ burst caused by CaP shell degradation triggered the Ca²⁺-mediated intense ER stress and subsequently induced mitochondria dysfunction to further boost ROS accumulation, which strengthens ferroptosis. The second Ca²⁺ burst occurred as a result of Ca²⁺ influx through ferroptotic pores on cell membranes, thus sequentially constructing the lethal "Ca²⁺ burst-ER stress-ferroptosis" cycle. Consequently, the Ca²⁺-burst-centered ER stress enhanced ferroptosis process was confirmed as a cell swelling and cell membrane disruption process driven by notable intracellular ROS and LPO accumulation. The proposed LDM showed an encouraging lung retention property and extraordinary antitumor ability in an orthotropic lung tumor murine model. In conclusion, the constructed ferroptosis nanoinducer could be a potential tailored nanoplatform for nebulization-based pulmonary delivery and underscore the application of Ca²⁺-burst-centered ER stress enhanced lung cancer ferroptosis therapy.

Artemisinin Loaded Cerium-Doped Nanopowders Improved In Vitro the Biomineralization in Human Periodontal Ligament Cells

BACKGROUND

A promising strategy to enhance bone regeneration is the use of bioactive materials doped with metallic ions with therapeutic effects and their combination with active substances and/or drugs. The aim of the present study was to investigate the osteogenic capacity of human periodontal ligament cells (hPDLCs) in culture with artemisinin (ART)-loaded Ce-doped calcium silicate nanopowders (NPs); Methods: Mesoporous silica, calcium-doped and calcium/cerium-doped silicate NPs were synthesized via a surfactant-assisted cooperative self-assembly process. Human periodontal ligament cells (hPDLCs) were isolated and tested for their osteogenic differentiation in the presence of ART-loaded and unloaded NPs through alkaline phosphatase (ALP) activity and Alizarine red S staining, while their antioxidant capacity was also evaluated; Results: ART promoted further the osteogenic differentiation of hPDLCs in the presence of Ce-doped NPs. Higher amounts of Ce in the ART-loaded NPs inversely affected the mineral deposition process by the hPDLCs. ART and Ce in the NPs have a synergistic role controlling the redox status and reducing ROS production from the hPDLCs; Conclusions: By monitoring the Ce amount and ART concentration, mesoporous NPs with optimum properties can be developed towards bone tissue regeneration demonstrating also potential application in periodontal tissue regeneration strategies.

Self-assembly and self-delivery of the pure nanodrug dihydroartemisinin for tumor therapy and mechanism analysis

Dihydroartemisinin (DHA), a plant-derived natural product, has recently been proven to be an effective therapeutic agent for cancer treatment. Nevertheless, the poor water solubility and low bioavailability of DHA seriously impede its clinical applications. Herein, a simple and green strategy based on the self-assembly of DHA was developed to synthesize carrier-free nanoparticles (NPs). The resulting nanodrug (DHA NPs) was formed by the self-assembly of DHA molecules via hydrogen bonding and hydrophobic interactions. The DHA NPs exhibited a near-spherical morphology with narrow size distribution, favorable drug encapsulation efficiency (>92%), excellent stability, and on-demand drug release behavior. Furthermore, the in vitro and in vivo experiments revealed that the DHA NPs exhibited significantly higher therapeutic efficacy than the DHA equivalent. In addition, we further explored the potential molecular mechanism of the DHA NPs by utilizing RNA-seq technology and western blotting analysis, which demonstrated that the p53 signaling pathway plays a crucial part in the process of inhibiting tumor cell growth and inducing apoptosis. This work not only reveals the rationale for developing pure nanodrugs via the self-assembly of natural small molecules for oncotherapy but also the investigation of the antitumor mechanism and provides novel theoretical support for the clinical usage of DHA.

Manganese-based hollow nanoplatforms for MR imaging-guided cancer therapies

Theranostic nanoplatforms integrating diagnostic and therapeutic functions have received considerable attention in the past decade. Among them, hollow manganese (Mn)-based nanoplatforms are superior since they combine the advantages of hollow structures and the intrinsic theranostic features of Mn²⁺. Specifically, the hollow cavity can encapsulate a variety of small-molecule drugs, such as chemotherapeutic agents, photosensitizers and photothermal agents, for chemotherapy, photodynamic therapy (PDT) and photothermal therapy (PTT), respectively. After degradation in the tumor microenvironment (TME), the released Mn²⁺ is able to act simultaneously as a magnetic resonance (MR) imaging contrast agent (CA) and as a Fenton-like agent for chemodynamic therapy (CDT). More importantly, synergistic treatment outcomes can be realized by reasonable and optimized design of the hollow nanosystems. This review summarizes various Mn-based hollow nanoplatforms, including hollow Mn_xO_y, hollow matrix-supported Mn_xO_y, hollow Mn-doped nanoparticles, hollow Mn complex-based nanoparticles, hollow Mn-cobalt (Co)-based nanoparticles, and hollow Mn-iron (Fe)-based nanoparticles, for MR imaging-guided cancer therapies. Finally, we discuss the potential obstacles and perspectives of these hollow Mn-based nanotheranostics for translational applications.

Artemisinin-Type Drugs in Tumor Cell Death: Mechanisms, Combination Treatment with Biologics and Nanoparticle Delivery

Artemisinin, the most famous anti-malaria drug initially extracted from Artemisia annua L., also exhibits anti-tumor properties in vivo and in vitro. To improve its solubility and bioavailability, multiple derivatives have been synthesized. However, to reveal the anti-tumor mechanism and improve the efficacy of these artemisinin-type drugs, studies have been conducted in recent years. In this review, we first provide an overview of the effect of artemisinin-type drugs on the regulated cell death pathways, which may uncover novel therapeutic approaches. Then, to overcome the shortcomings of artemisinin-type drugs, we summarize the recent advances in two different therapeutic approaches, namely the combination therapy with biologics influencing regulated cell death, and the use of nanocarriers as drug delivery systems. For the former approach, we discuss the superiority of combination treatments compared to monotherapy in tumor cells based on their effects on regulated cell death. For the latter approach, we give a systematic overview of nanocarrier design principles used to deliver artemisinin-type drugs, including inorganic-based nanoparticles, liposomes, micelles, polymer-based nanoparticles, carbon-based nanoparticles, nanostructured lipid carriers and niosomes. Both approaches have yielded promising findings in vitro and in vivo, providing a strong scientific basis for further study and upcoming clinical trials.

Repurposing Artemisinin and its Derivatives as Anticancer Drugs: A Chance or Challenge?

Cancer has become a global health problem, accounting for one out of six deaths. Despite the recent advances in cancer therapy, there is still an ever-growing need for readily accessible new therapies. The process of drug discovery and development is arduous and takes many years, and while it is ongoing, the time for the current lead compounds to reach clinical trial phase is very long. Drug repurposing has recently gained significant attention as it expedites the process of discovering new entities for anticancer therapy. One such potential candidate is the antimalarial drug, artemisinin that has shown anticancer activities in vitro and in vivo. In this review, major molecular and cellular mechanisms underlying the anticancer effect of artemisinin and its derivatives are summarised. Furthermore, major mechanisms of action and some key signaling pathways of this group of compounds have been reviewed to explore potential targets that contribute to the proliferation and metastasis of tumor cells. Despite its established profile in malaria treatment, pharmacokinetic properties, anticancer potency, and current formulations that hinder the clinical translation of artemisinin as an anticancer agent, have been discussed. Finally, potential solutions or new strategies are identified to overcome the bottlenecks in repurposing artemisinin-type compounds as anticancer drugs.

Hemin-lipid assembly as an artemisinin oral delivery system for enhanced cancer chemotherapy and immunotherapy

Although artemisinin (ART) has shown initial promise in cancer therapy, its therapeutic efficacy is limited by its low tumor inhibitory efficacy and unfavorable distribution. Considering the important role of heme in the specific parasite-killing effect of ART, we designed a liposomal nanostructure self-assembled from hemin-lipid (Hemesome) to co-deliver ART and hemin for cancer therapy. The synergistic chemotherapeutic and immunotherapeutic effects of hemin and ART were demonstrated both in vitro and in vivo. The liposome-like structure was relatively stable in the blood circulation and gastrointestinal tract environment, but dissociated in the tumor cell environment. The folic acid (FA) modification not only increased their efficiency for transport across the epithelium, but also increased their tumor accumulation. In mouse models, following oral administration of FA-Hemesome-ART nanoparticles (5 mg kg^-1 ART in total) every other day and intraperitoneal injection with a programmed death-ligand 1 antibody (aPD-L1, 70 μg per mouse in total), MC38 tumors were completely inhibited within 30 days. The cured mice remained tumor-free 30 days after rechallenging them with another inoculation of MC38 cells due to the strong immune memory effect.

Bioinspired Microenvironment Responsive Nanoprodrug as an Efficient Hydrophobic Drug Self-Delivery System for Cancer Therapy

Artemisinin compounds have shown satisfactory safety records in anti-malarial clinical practice over decades and have revealed value as inexpensive anti-tumor adjuvant chemotherapeutic drugs. However, the rational design and precise preparation of nanomedicines based on the artemisinin drugs are still limited due to their non-aromatic and fragile chemical structure. Herein, a bioinspired coordination-driven self-assembly strategy was developed to manufacture the artemisinin-based nanoprodrug with a significantly increased drug loading efficacy (∼70 wt %) and decreased preparation complexity compared to conventional nanodrugs. The nanoprodrug has suitable size distribution and robust colloidal stability for cancer targeting in vivo. The nanoprodrug was able to quickly disassemble in the tumor microenvironment with weak acidity and a high glutathione concentration, which guarantees a better tumor inhibitory effect than direct administration and fewer side effects on normal tissues in vivo. This work highlights a new strategy to harness a robust, simplified, organic solvent-free, and highly repeatable route for nanoprodrug manufacturing, which may offer opportunities to develop cost-effective, safe, and clinically available nanomedicines.

Artemisinin co-delivery system based on manganese oxide for precise diagnosis and treatment of breast cancer

Tumor microenvironment (TME) responsive intelligent system can realize the specific release and uniform distribution of chemotherapy drugs in tumor tissues, to achieve high-efficiency and low-toxic treatment of tumors. In this paper, drug delivery system TKD@RBCm-Mn₂O₃-ART with the above characteristics was constructed. We synthesized hollow mesoporous manganese trioxide (Mn₂O₃) nanoparticles and firstly found that they owned time-dependent size transformation feature in simulated TME. The particle size decreased from 318 nm to 50 nm and 6 nm at 1 h and 4 h in simulated TME, respectively. Then artemisinin (ART) was loaded into Mn₂O₃to realize the co-delivery of Mn²⁺and ART. The modification of homologous red cell membrane (RBCm) and TKD peptide was aimed at long circulation and tumor targeting in the body.In vitroresults demonstrated that in the presence of GSH, the cumulative drug release percentage could achieve 97.5%. Meanwhile, Mn₂O₃exhibited a good imaging capability in tumor, with the relaxation rate of 6.3113 mM^-1s^-1. After entering into MCF-7 cells, TKD@RBCm-Mn₂O₃/ART synchronously released Mn²⁺and ART to generate large amount of ROS and induce DNA damage.In vivoresults proved TKD@RBCm-Mn₂O₃/ART could arrive the deep area of solid tumors and achieve accurate diagnosis and treatment of breast cancer.

Dihydroartemisinin loaded layered double hydroxide nanocomposites for tumor specific photothermal-chemodynamic therapy

With the inspiration to develop new cancer nanotherapeutics by repurposing old drugs, in the current study, a novel two dimensional nanomedicine namely Mn doped, dihydroartemisinin (DHA) loaded layered double hydroxide (MnMgFe-LDH/DHA) with peroxide self-supplying properties for enhanced photothermal-chemodynamic therapy was proposed. Such nanostructures could be synthesized by a simple coprecipitation method, and the as-prepared MnMgFe-LDH/DHA exhibits excellent photothermal properties with a photothermal conversion efficiency up to 10.7%. Besides, the in situ reaction between the released DHA and Fe2+/Mn2+ produced by the degradation of LDH can lead to a burst of intracellular reactive oxygen species (ROS) by Fenton-like reactions. Furthermore, the in vivo experiments demonstrate that MnMgFe-LDH/DHA exhibits a remarkable chemodynamic/photothermal therapy (CDT/PTT) synergistic effect on tumor treatment with negligible damage to normal tissues. Finally, this research provides a smart strategy to construct a DHA repurposing nanomedicine for tumor specific treatment.

Smart Responsive Nanoformulation for Targeted Delivery of Active Compounds From Traditional Chinese Medicine

Traditional Chinese medicine (TCM) has been used to treat disorders in China for ~1,000 years. Growing evidence has shown that the active ingredients from TCM have antibacterial, antiproliferative, antioxidant, and apoptosis-inducing features. However, poor solubility and low bioavailability limit clinical application of active compounds from TCM. “Nanoformulations” (NFs) are novel and advanced drug-delivery systems. They show promise for improving the solubility and bioavailability of drugs. In particular, “smart responsive NFs” can respond to the special external and internal stimuli in targeted sites to release loaded drugs, which enables them to control the release of drug within target tissues. Recent studies have demonstrated that smart responsive NFs can achieve targeted release of active compounds from TCM at disease sites to increase their concentrations in diseased tissues and reduce the number of adverse effects. Here, we review “internal stimulus–responsive NFs” (based on pH and redox status) and “external stimulus–responsive NFs” (based on light and magnetic fields) and focus on their application for active compounds from TCM against tumors and infectious diseases, to further boost the development of TCM in modern medicine.

Artemisinins as Anticancer Drugs: Novel Therapeutic Approaches, Molecular Mechanisms, and Clinical Trials

Artemisinin and its derivatives have shown broad-spectrum antitumor activities in vitro and in vivo. Furthermore, outcomes from a limited number of clinical trials provide encouraging evidence for their excellent antitumor activities. However, some problems such as poor solubility, toxicity and controversial mechanisms of action hamper their use as effective antitumor agents in the clinic. In order to accelerate the use of ARTs in the clinic, researchers have recently developed novel therapeutic approaches including developing novel derivatives, manufacturing novel nano-formulations, and combining ARTs with other drugs for cancer therapy. The related mechanisms of action were explored. This review describes ARTs used to induce non-apoptotic cell death containing oncosis, autophagy, and ferroptosis. Moreover, it highlights the ARTs-caused effects on cancer metabolism, immunosuppression and cancer stem cells and discusses clinical trials of ARTs used to treat cancer. The review provides additional insight into the molecular mechanism of action of ARTs and their considerable clinical potential.

Targeted GSH-exhausting and hydroxyl radical self-producing manganese-silica nanomissiles for MRI guided ferroptotic cancer therapy

Ferroptosis, a cell death path induced by the generation of reactive oxygen species (ROS), will cause the accumulation of lipid peroxides (PL-PUFA-OOH) and achieve potent tumor-regression. However, glutathione (GSH)-dependent glutathione peroxidase 4 (GPx4) can reduce PL-PUFA-OOH and antagonize the ferroptosis inducing effect of ROS. Herein, folate-PEG modified dihydroartemisinin (DHA) loaded manganese doped mesoporous silica nanoparticles (described as nanomissiles) were constructed for integrating the effect of GSH exhaustion and ROS generation. After endocytosis by tumor cells, intracellular GSH triggered the degradation of nanomissiles, which allowed the simultaneous release of DHA and Fenton catalytic Mn2+ due to the redox reaction between the manganese-oxygen bonds and GSH. The degradation would lead to GSH exhaustion, activation of Mn2+-based magnetic resonance imaging (MRI), and DHA-driven ˙OH generation. The GSH-free environment inhibited the activity of GPx4 and enhanced the accumulation of PL-PUFA-OOH oxidized by ˙OH. Furthermore, the cooperative effects suppressed tumor metastasis by destroying the structure of polyunsaturated fatty acids in the cell membranes and showed potent antitumor activity. This innovative ferroptotic therapy integrating the GSH exhaustion and ROS generation will be a promising strategy for cancer therapy.

Gas-blasting nanocapsules to accelerate carboplatin lysosome release and nucleus delivery for prostate cancer treatment

To improve therapeutic effect and reduce severely side effects of carboplatin (CBP), the gas-generating nanocapsules were developed to accelerate CBP lysosome release and nucleus delivery. CBP/SB-NC was prepared by co-loading CBP and NaHCO₃ (SB) in nanocapsules using w/o/w emulsification solvent evaporation. They exhibited vesicle-like spherical morphology, uniform particle size and negative zeta potential. Reaching the tumor site with a relatively high concentration is the first step for CBP delivery and the results showed that CBP/SB-NC could effectively increase drug accumulation at tumor site. After that, the drug delivery carriers need to be internalized into tumor cells and the in vitro cellular uptake ability results showed CBP/SB-NC could be internalized into RM-1 cells more efficient than CBP solution. After internalized by RM-1 cells, the gas-blasting release process was tested in acid environment. It was demonstrated that 5 mg/ml NaHCO₃ was optimal to achieve pH-responsive gas-blasting release. In vitro release results showed that CBP significantly rapid release in acid environment (pH 5.0) compared to neutral pH (pH 7.4) (P < 0.05). Meanwhile, TEM and the change of the concentration of H⁺ results exhibited that the explosion of CBP/SB₅-NC was more easily happened in lysosome acid environment (pH 5.0). The blasting release can accelerate CBP lysosome release to cytoplasm. Furthermore, the nucleus delivery results showed CBP/SB₅-NC can promote pH-triggered rapid nucleus delivery. And the results of Pt-DNA adduct assay showed that the binding efficiency between CBP and DNA of CBP/SB₅-NC was higher than CBP solution. At last, in vitro and in vivo anti-tumor efficacy proved that CBP/SB₅-NC could enhance anti-tumor activity for prostate cancer therapy. CBP/SB₅-NC also showed superior safety in vitro and in vivo by hemolysis assay and histopathological study. All of the results demonstrate that CBP/SB₅-NC would be an efficient gas-blasting release formulation to enhance prostate cancer treatment.

Recent Progresses in Cancer Nanotherapeutics Design Using Artemisinins as Free Radical Precursors

Artemisinin and its derivatives (ARTs) are sort of important antimalarials, which exhibit a wide range of biological activities including anticancer effect. To solve the issues regarding poor solubility and limited bioavailability of ARTs, nanoformulation of ARTs has thus emerged as a promising strategy for cancer treatment. A common consideration on nanoARTs design lies on ARTs' delivery and controlled release, where ARTs are commonly regarded as hydrophobic drugs. Based on the mechanism that ARTs' activation relies on ferrous ions (Fe2+) or Fe2+-bonded complexes, new designs to enhance ARTs' activation have thus attracted great interests for advanced cancer nanotherapy. Among these developments, the design of a nanoparticle that can accelerate ARTs' activation has become the major consideration, where ARTs have been regarded as radical precursors. This review mainly focused on the most recent developments of ARTs nanotherapeutics on the basis of advanced drug activation. The basic principles in those designs will be summarized, and a few excellent cases will be also discussed in detail.

A glutathione-depleted prodrug platform of MnO2-coated hollow polydopamine nanospheres for effective cancer diagnosis and therapy

A biocompatible and efficient nanoplatform for tumor diagnosis and treatment was fabricated based on manganese oxide-coated hollow polydopamine loaded with dihydroartemisinin.

Nanoparticle facilitated delivery of peroxides for effective cancer treatments

Peroxide nanoparticles increase the intratumoral H₂O₂ concentration for the catalytic production of ˙OH and O₂, which further enhance O₂/ROS-dependent anticancer therapies.

A smart drug-delivery nanosystem based on carboxylated graphene quantum dots for tumor-targeted chemotherapy

Aim: Constructing a new drug-delivery system using carboxylated graphene quantum dots (cGQDs) for tumor chemotherapy in vivo. Materials & methods: A drug-delivery system was synthesized through a crosslink reaction of cGQDs, NH2-poly(ethylene glycol)-NH2 and folic acid. Results: A drug delivery system of folic acid-poly(ethylene glycol)-cGQDs was successfully constructed with ideal entrapment efficiency (97.5%) and drug-loading capacity (40.1%). Cell image indicated that the nanosystem entered into human cervical cancer cells mainly through macropinocytosis-dependent pathway. In vivo experiments showed the outstanding antitumor ability and low systemic toxicity of this nanodrug-delivery system. Conclusion: The newly developed drug-delivery system provides an important alternative for tumor therapy without causing systemic adverse effects.

Biocompatible Heat-Shock Protein Inhibitor-Delivered Flowerlike Short-Wave Infrared Nanoprobe for Mild Temperature-Driven Highly Efficient Tumor Ablation

Multifunctional nanomaterials for dual-mode imaging guided cancer therapy are highly desirable in clinical applications. Herein, a flowerlike NiS₂-coated NaLuF₄:Nd (Lu:Nd@NiS₂) nanoparticle was synthesized as a novel therapeutic agent for short-wave infrared light imaging and magnetic resonance imaging to guide photothermal therapy (PTT). The material was then loaded with phenolic epigallocatechin 3-gallate (EGCG), which is a natural heat-shock protein 90 (HSP90) inhibitor. Upon near infrared irradiation, EGCG was released from the Lu:Nd@NiS₂-EGCG, which bound HSP90 and reduced cell tolerance to heat, resulting in a better therapeutic effect at the same elevated temperature. Therefore, with minimal side effects and remarkable antitumor efficacy in vivo, Lu:Nd@NiS₂-EGCG appeared to be a promising photothermal agent for enhanced PTT.

Fe3O4@SiO2mesoporous spheres as Fe(ii) donors loaded with artemisinin and a photosensitizer to alleviate tumor hypoxia in PDT for enhanced anticancer therapy

Fe₃O₄@SiO₂as an Fe(ii) donor loaded with artemisinin and photosensitizer to alleviate hypoxia in PDT showed excellent anticancer activity.

Three peroxidovanadium(v) compounds mediated by transition metal cations for enhanced anticancer activity

The mediation of transition metal cations leads to superior antiproliferative activity and cell-type selectivity of peroxidovanadium(v) compounds.

Poly(norepinephrine)-coated FeOOH nanoparticles as carriers of artemisinin for cancer photothermal-chemical combination therapy

The photothermal-chemical combination therapy is a promising approach for cancer treatment, however, chemotherapy often causes severe toxic and side effects on normal tissues. Herein, tumor-specific FeOOH@PNE-Art nanoparticles were fabricated via coating poly(norepinephrine) (PNE) on FeOOH nanoparticles, followed by loading of artemisinin (Art). The as-prepared nanoparticles exhibited excellent biocompatibility, strong near-infrared (NIR) absorbance and pH-responsive synchronous release of Art and iron ions. The released iron ions could not only supply iron ions in cancer cells which mediate endoperoxide bridge cleavage of Art and generate reactive oxygen species (ROS), but also react with H₂O₂ at tumour sites via the Fenton reaction and produce hydroxyl radicals, inducing a tumour-specific killing. Moreover, owing to the synchronous release of Art and iron ions as well as the low leakage of iron ions, FeOOH@PNE-Art nanoparticles showed extremely low toxicity to normal tissue. Under NIR light irradiation, the tumours in FeOOH@PNE-Art injected mice were thoroughly eliminated after 7 days of treatment and no tumour recurrence was found 30 days after treatment, manifesting very high efficacy of combination therapy.

Tumor-specific FeOOH@PNE-Art nanoparticles were fabricated that showed high efficacy of photothermal-chemical combination therapy and low toxicity to normal tissue.

Antitumor Research on Artemisinin and Its Bioactive Derivatives

Cancer is the leading cause of human death which seriously threatens human life. The antimalarial drug artemisinin and its derivatives have been discovered with considerable anticancer properties. Simultaneously, a variety of target-selective artemisinin-related compounds with high efficiency have been discovered. Many researches indicated that artemisinin-related compounds have cytotoxic effects against a variety of cancer cells through pleiotropic effects, including inhibiting the proliferation of tumor cells, promoting apoptosis, inducing cell cycle arrest, disrupting cancer invasion and metastasis, preventing angiogenesis, mediating the tumor-related signaling pathways, and regulating tumor microenvironment. More importantly, artemisinins demonstrated minor side effects to normal cells and manifested the ability to overcome multidrug-resistance which is widely observed in cancer patients. Therefore, we concentrated on the new advances and development of artemisinin and its derivatives as potential antitumor agents in recent 5 years. It is our hope that this review could be helpful for further exploration of novel artemisinin-related antitumor agents.

Artemisinin-Loaded Mesoporous Nanoplatform for pH-Responsive Radical Generation Synergistic Tumor Theranostics

The development of novel and effective cancer treatments will greatly contribute to prolonging and improving patient lives. In this study, a multifunctional nanoplatform was designed and developed based on mesoporous NiO (mNiO) nanoparticles and terbium complexes as an artemisinin (ART) vehicle, a T₂-weighted contrast agent, and a luminescence imaging probe. mNiO is a novel pH-responsive material that can degrade and release nickel ions (Ni²⁺) in an acidic tumor microenvironment. The endoperoxide bridge bond in the structure of ART tends to react with Ni²⁺ to produce radicals that can kill tumor cells. On the basis of its excellent near-infrared absorbance, mNiO can also be considered as a novel photothermal conversion agent for cancer photothermal therapy (PTT). Compared with free ART or PTT only, this novel agent showed remarkably enhanced antitumor activity in cultured cells and in tumor mice models, owing to the hypoxic tumor microenvironment impelling synergistic therapeutic action. These results provide a novel way of using a promising natural drug-based nanoplatform for synergistic therapy of tumors.

Facile total synthesis of lysicamine and the anticancer activities of the RuII, RhIII, MnII and ZnII complexes of lysicamine

Lysicamine is a natural oxoaporphine alkaloid, which isolated from traditional Chinese medicine (TCM) herbs and has been shown to possess cytotoxicity to hepatocarcinoma cell lines. Reports on its antitumor activity are scarce because lysicamine occurs in plants at a low content. In this work, we demonstrate a facile concise total synthesis of lysicamine from simple raw materials under mild reaction conditions, and the preparation of the Ru(II), Rh(III), Mn(II) and Zn(II) complexes 1–4 of lysicamine (LY). All the compounds were fully characterized by elemental analysis, IR, ESI-MS, ¹H and ¹³C NMR, as well as single-crystal X-ray diffraction analysis. Compared with the free ligand LY, complexes 2 and 3 exhibited superior in vitro cytotoxicity against HepG2 and NCI-H460. Mechanistic studies indicated that 2 and 3 blocked the cell cycle in the S phase by decreasing of cyclins A2/B1/D1/E1, CDK 2/6, and PCNA levels and increasing levels of p21, p27, p53 and CDC25A proteins. In addition, 2 and 3 induced cell apoptosis via both the caspase-dependent mitochondrial pathway and the death receptor pathway. in vivo study showed that 2 inhibited HepG2 tumor growth at 1/3 maximum tolerated dose (MTD) and had a better safety profile than cisplatin.

Artemisinin as an anticancer drug: Recent advances in target profiling and mechanisms of action

Artemisinin and its derivatives (collectively termed as artemisinins) are among the most important and effective antimalarial drugs, with proven safety and efficacy in clinical use. Beyond their antimalarial effects, artemisinins have also been shown to possess selective anticancer properties, demonstrating cytotoxic effects against a wide range of cancer types both in vitro and in vivo. These effects appear to be mediated by artemisinin-induced changes in multiple signaling pathways, interfering simultaneously with multiple hallmarks of cancer. Great strides have been taken to characterize these pathways and to reveal their anticancer mechanisms of action of artemisinin. Moreover, encouraging data have also been obtained from a limited number of clinical trials to support their anticancer property. However, there are several key gaps in knowledge that continue to serve as significant barriers to the repurposing of artemisinins as effective anticancer agents. This review focuses on important and emerging aspects of this field, highlighting breakthroughs in unresolved questions as well as novel techniques and approaches that have been taken in recent studies. We discuss the mechanism of artemisinin activation in cancer, novel and significant findings with regards to artemisinin target proteins and pathways, new understandings in artemisinin-induced cell death mechanisms, as well as the practical issues of repurposing artemisinin. We believe these will be important topics in realizing the potential of artemisinin and its derivatives as safe and potent anticancer agents.

Reactive oxygen species generating systems meeting challenges of photodynamic cancer therapy

The reactive oxygen species (ROS)-mediated mechanism is the major cause underlying the efficacy of photodynamic therapy (PDT). The PDT procedure is based on the cascade of synergistic effects between light, a photosensitizer (PS) and oxygen, which greatly favors the spatiotemporal control of the treatment. This procedure has also evoked several unresolved challenges at different levels including (i) the limited penetration depth of light, which restricts traditional PDT to superficial tumours; (ii) oxygen reliance does not allow PDT treatment of hypoxic tumours; (iii) light can complicate the phototherapeutic outcomes because of the concurrent heat generation; (iv) specific delivery of PSs to sub-cellular organelles for exerting effective toxicity remains an issue; and (v) side effects from undesirable white-light activation and self-catalysation of traditional PSs. Recent advances in nanotechnology and nanomedicine have provided new opportunities to develop ROS-generating systems through photodynamic or non-photodynamic procedures while tackling the challenges of the current PDT approaches. In this review, we summarize the current status and discuss the possible opportunities for ROS generation for cancer therapy. We hope this review will spur pre-clinical research and clinical practice for ROS-mediated tumour treatments.

Magnetic and fluorescent carbon-based nanohybrids for multi-modal imaging and magnetic field/NIR light responsive drug carriers

This mini-review summarizes the latest developments and addresses the future perspectives of carbon-based magnetic and fluorescent nanohybrids in the biomedical field.

Two-stage pH-sensitive doxorubicin hydrochloride loaded core–shell nanoparticles with dual drug-loading strategies for the potential anti-tumor treatment

Two-stage pH-sensitive DOX·HCl loaded core–shell nanoparticles (CPOD) with dual drug-loading strategies showed pretty in vivo anti-tumor efficacy.