Developments and future clinical outlook of taxane nanomedicines

FAERS based disproportionality analysis and network pharmacology investigation of taxanes associated drug induced liver injury

Taxanes play a crucial role in cancer treatment, particularly for non-small cell lung cancer and breast cancer. However, real-world studies examining drug-induced liver injury (DILI) associated with these drugs remain limited. Our study investigates the association between taxanes and DILI through analysis of the Food and Drug Administration Adverse Event Reporting System (FAERS) database, alongside an exploration of potential hepatotoxicity mechanisms via network pharmacology. We collected DILI reports related to taxanes from the FAERS database between January 2004 and March 2024, employing disproportionality analyses with the reporting odds ratio (ROR) and 95% confidence intervals. Our findings revealed a significant association between paclitaxel (ROR = 2.35) and nab-paclitaxel (ROR = 3.14) with DILI, while docetaxel demonstrated no significant correlation (ROR = 0.68), although it was linked to higher mortality rates and earlier onset. Network pharmacology analysis uncovered that the mechanisms of liver injury induced by these two drugs may not be entirely congruent. Unique targets for docetaxel included BCL2, CNR2, and MAPK1, while the 'Regulation of lipolysis in adipocytes' pathway was specifically associated with docetaxel-induced DILI. Our findings indicate that taxanes exhibit differential hepatotoxic risks and hepatotoxicity mechanisms, emphasizing the need for enhanced drug safety monitoring strategies for cancer patients.

A computer-aided, heterodimer-based "triadic" carrier-free drug delivery platform to mitigate multidrug resistance in lung cancer and enhance efficiency

Co-delivering multiple drugs or circumventing the drug efflux mechanism can significantly decrease multidrug resistance (MDR), a major cause of cancer treatment failure. In this study, we designed and fabricated a universal "three-in-one" self-delivery system for synergistic cancer therapy using a computer-aided strategy. First, we engineered two glutathione (GSH)-responsive heterodimers, ERL-SS-CPT (erlotinib [ERL] linked with camptothecin [CPT] via a disulfide bond [SS]) and CPT-SS-ERI (CPT conjugated with erianin [ERI]), which serve as both cargo and carrier material. Next, molecular dynamics simulations indicated that multiple noncovalent molecular forces, including π-π stacking, hydrogen bonds, hydrophobic interactions, and sulfur bonds, drive the self-assembly process of these heterodimers. We then explored the universality of the heterodimers and developed a "triadic" drug delivery platform comprising 40 variants. Subsequently, we conducted case studies on docetaxel (DTX)-loaded ERL-SS-CPT nanoparticles (denoted as DTX@ERL-SS-CPT NPs) and curcumin (CUR)-loaded ERL-SS-CPT NPs (identified as CUR@CPT-SS-ERI NPs) to comprehensively investigate their self-assembly mechanism, physicochemical properties, storage stability, GSH-responsive drug release, cellular uptake, apoptosis effects, biocompatibility, and cytotoxicity. Both NPs exhibited well-defined spherical structures, high drug loading rates, and excellent storage stability. DTX@ERL-SS-CPT NPs exhibited the strongest cytotoxicity in A549 cells, following the order of DTX@ERL-SS-CPT NPs > ERL-SS-CPT NPs > CPT > DTX > ERL. Conversely, DTX@ERL-SS-CPT NPs showed negligible cytotoxicity in normal human bronchial epithelium cell line (BEAS-2B), indicating good biocompatibility and safety. Similar observations were made for CUR@CPT-SS-ERI NPs regarding biocompatibility and cytotoxicity. Upon endocytosis and encountering intracellular overexpressed GSH, the disulfide-bond linker is cleaved, resulting in the release of the versatile NPs into three parts. The spherical NPs enhance water solubility, reduce the required dosage of free drugs, and increase cellular drug accumulation while suppressing P-glycoprotein (P-gp) expression, leading to apoptosis. This work provides a computer-aided universal strategy-a heterodimer-based "triadic" drug delivery platform-to enhance anticancer efficiency while reducing multidrug resistance.

An Efficient Method for Vault Nanoparticle Conjugation with Finely Adjustable Amounts of Antibodies and Small Molecules

Vaults are eukaryotic ribonucleoproteins consisting of 78 copies of the major vault protein (MVP), which assemble into a nanoparticle with an about 60 nm volume-based size, enclosing other proteins and RNAs. Regardless of their physiological role(s), vaults represent ideal, natural hollow nanoparticles, which are produced by the assembly of the sole MVP. Here, we have expressed in Komagataella phaffi and purified an MVP variant carrying a C-terminal Z peptide (vault-Z), which can tightly bind an antibody's Fc portion, in view of targeted delivery. Via surface plasmon resonance analysis, we could determine a 2.5 nM affinity to the monoclonal antibody Trastuzumab (Tz)/vault-Z 1:1 interaction. Then, we characterized the in-solution interaction via co-incubation, ultracentrifugation, and analysis of the pelleted proteins. This showed virtually irreversible binding up to an at least 10:1 Tz/vault-Z ratio. As a proof of concept, we labeled the Fc portion of Tz with a fluorophore and conjugated it with the nanoparticle, along with either Tz or Cetuximab, another monoclonal antibody. Thus, we could demonstrate antibody-dependent, selective uptake by the SKBR3 and MDA-MB 231 breast cancer cell lines. These investigations provide a novel, flexible technological platform that significantly extends vault-Z's applications, in that it can be stably conjugated with finely adjusted amounts of antibodies as well as of other molecules, such as fluorophores, cell-targeting peptides, or drugs, using the Fc portion as a scaffold.

Formulation and evaluation of paclitaxel-loaded boronated chitosan/alginate nanoparticles as a mucoadhesive system for localized cervical cancer drug delivery

Cervical cancer remains a significant global health challenge, and there is a need for innovative drug delivery systems to improve the efficacy of anticancer drugs. In this study, we developed and evaluated boronated chitosan/alginate nanoparticles (BCHIALG NPs) as a localized mucoadhesive drug delivery system for cervical cancer. Boronated chitosan (BCHI) was synthesized by incorporating 4-carboxyphenylboronic acid onto chitosan (CHI), and boronated chitosan/alginate nanoparticles (BCHIALG NPs) with varying polymer ratios were prepared using an ionic gelation method. The physical properties, drug loading capacity/encapsulation efficiency, mucoadhesive properties, and in vitro drug release profile of the nanoparticles were evaluated. The BCHIALG NPs exhibited a size of less than 390 nm and demonstrated high drug encapsulation efficiency (98.1 - 99.8%) and loading capacity (326.9 - 332.7 μg/mg). Remarkably, the BCHIALG NPs containing 0.03% boronated chitosan and 0.07% alginate showed superior mucoadhesive capability compared to CHIALG NPs, providing sustained drug release and they showed the most promising results as a transmucosal drug delivery system for hydrophobic drugs like paclitaxel (PTX). To the best of our knowledge, this is the first report investigating BCHIALG NPs for cervical drug delivery. The new mucoadhesive paclitaxel formulation could offer an innovative strategy for improving cervical cancer treatment.

New SDS-Based Polyelectrolyte Multicore Nanocarriers for Paclitaxel Delivery-Synthesis, Characterization, and Activity against Breast Cancer Cells

The low distribution of hydrophobic anticancer drugs in patients is one of the biggest limitations during conventional chemotherapy. SDS-based polyelectrolyte multicore nanocarriers (NCs) prepared according to the layer by layer (LbL) procedure can release paclitaxel (PTX), and selectively kill cancer cells. Our main objective was to verify the antitumor properties of PTX-loaded NCs and to examine whether the drug encapsulated in these NCs retained its cytotoxic properties. The cytotoxicity of the prepared nanosystems was tested on MCF-7 and MDA-MB-231 tumour cells and the non-cancerous HMEC-1 cell line in vitro. Confocal microscopy, spectrophotometry, spectrofluorimetry, flow cytometry, and RT PCR techniques were used to define the typical hallmarks of apoptosis. It was demonstrated that PTX encapsulated in the tested NCs exhibited similar cytotoxicity to the free drug, especially in the triple negative breast cancer model. Moreover, SDS/PLL/PTX and SDS/PLL/PGA/PTX significantly reduced DNA synthesis. In addition, PTX-loaded NCs triggered apoptosis and upregulated the transcription of Bax, AIF, cytochrome-c, and caspase-3 mRNA. Our data demonstrate that these novel polyelectrolyte multicore NCs coated with PLL or PLL/PGA are good candidates for delivering PTX. Our discoveries have prominent implications for the possible choice of newly synthesized, SDS-based polyelectrolyte multicore NCs in different anticancer therapeutic applications.

RGD-directed 24 nm micellar docetaxel enables elevated tumor-liver ratio, deep tumor penetration and potent suppression of solid tumors

Nanomedicines while showing a great potential in improving the performance of chemotherapeutics like docetaxel (DTX) are distressed by a high liver deposition and poor tumor penetration, which might not only cause liver toxicity but also moderate therapeutic effect. Herein, we report that cRGD-directed 24 nm disulfide-crosslinked micellar docetaxel (cRGD-MDTX) presents low liver accumulation, high tumor uptake, and deep tumor penetration, leading to the potent suppression of different solid tumors. cRGD-MDTX was optimized with a cRGD density of 4% and DTX loading of 10 wt%. Interestingly, cRGD-MDTX enabled an extraordinary tumor-liver ratio of 2.8/1 with a DTX uptake of 8.3 %ID/g in αvβ3 over-expressing PC3 prostate tumor. The therapeutic studies demonstrated striking antitumor effects of cRGD-MDTX toward PC3 prostate tumor, prostate cancer patient-derived xenografts (PDX), orthotopic A549-Luc lung cancer and orthotopic SKOV3-Luc ovarian tumor models, in which tumor growth was effectually inhibited and 6-8 times better improvement of median survival time over free DTX was observed. This small disulfide-crosslinked micellar drug capable of relegating liver deposition opens a new avenue to nanomedicines for targeted therapy.

Rational Engineering Docetaxel Prodrug Nanoassemblies: Response Modules Guiding Efficacy Enhancement and Toxicity Reduction

Prodrug-based nanoassemblies have been developed to solve the bottlenecks of chemotherapeutic drugs. The fabricated prodrugs usually consist of active drug modules, response modules, and modification modules. Among three modules, the response modules play a vital role in controlling the intelligent drug release at tumor sites. Herein, various locations of disulfide bond linkages were selected as response modules to construct three Docetaxel (DTX) prodrugs. Interestingly, the small structural difference caused by the length of response modules endowed corresponding prodrug nanoassemblies with unique characteristic. α-DTX-OD nanoparticles (NPs) possessed the advantages of high redox-responsiveness due to their shortest linkages. However, they were too sensitive to retain the intact structure in the blood circulation, leading to severe systematic toxicity. β-DTX-OD NPs significantly improved the pharmacokinetics of DTX but may induce damage to the liver. In comparison, γ-DTX-OD NPs with the longest linkages greatly ameliorated the delivery efficiency of DTX as well as improved DTX's tolerance dose.

Progress and prospects of modified starch-based carriers in anticancer drug delivery

Recently, the role of starch-based carrier systems in anticancer drug delivery has gained considerable attention. Although there are same anticancer drugs, difference in their formulations account for unique therapeutic effects. However, the exploration on the effect-enhancing of anticancer drugs and their loading system by modified starch from the perspective of carrier regulation is still limited. Moreover, research on the reduced toxicity of the anticancer drugs due to modified starch as the drug carrier mediated by the intestinal microenvironment is lacking, but worth exploring. In this review, we examined the effect of modified starch on the loading and release properties of anticancer drugs, and the effect of resistant starch and its metabolites on intestinal microecology during inflammation. Particularly, the interactions between modified starch and drugs, and the effect of resistant starch on gene expression, protein secretion, and inflammatory factors were discussed. The findings of this review could serve as reference for the development of anticancer drug carriers in the future.

Albumin-Bound Paclitaxel: Worthy of Further Study in Sarcomas

Taxanes (paclitaxel and docetaxel) play an important role in the treatment of advanced sarcomas. Albumin-bound paclitaxel (nab-paclitaxel) is a new kind of taxane and has many advantages compared with paclitaxel and docetaxel. Nab-paclitaxel is currently approved for the treatment of advanced breast, non-small cell lung, and pancreatic cancers. However, the efficacy of nab-paclitaxel in sarcomas has not been reviewed. In this review, we first compare the similarities and differences among nab-paclitaxel, paclitaxel, and docetaxel and then summarize the efficacy of nab-paclitaxel against various non-sarcoma malignancies based on clinical trials with reported results. The efficacy and clinical research progress on nab-paclitaxel in sarcomas are also summarized. This review will serve as a good reference for the application of nab-paclitaxel in clinical sarcoma treatment studies and the design of clinical trials.

Probing the new strategy for the oral formulations of taxanes: changing the method with the situation

The first-generation taxanes (including paclitaxel and docetaxel) are widely used for the treatment of various cancers in clinical settings. In the past decade, a series of new-generation taxanes have been developed which are effective in the inhibition of tumor resistance. However, intravenous (i.v.) infusion is still the only route of administration, and may result in serious adverse reactions with respect to the utilization of Cremophor EL or Tween-80 as solvent. Besides, the dosing schedule is also limited. Therefore, oral administration of taxanes is urgently needed to avoid the adverse reactionss and increase dosing frequency. In this review, we first outlined the discovery and development of taxane-based anticancer agents. Furthermore, we summarized the research progress on the oral formulations of taxanes and proposed some thoughts on the future development of oral taxane formulations.

Self-assembled supramolecular nanomicelles from a bile acid-docetaxel conjugate are highly tolerable with improved therapeutic efficacy

Herein, we present the engineering of a supramolecular nanomicellar system that is composed of self-assembled units of the PEGylated lithocholic acid (LCA)-docetaxel (DTX) conjugate (LCA-DTX-PEG). We tethered a short polyethylene glycol unit to LCA and used an esterase-sensitive ester linkage between DTX and LCA. The LCA-DTX-PEG conjugate formed nanomicelles (LCA-DTX-PEG NMs) with ∼160 nm hydrodynamic diameter that are sensitive to cellular esterases and maximized the release of DTX under high esterase exposure. LCA-DTX-PEG NMs were found to be effective as the parent drug in breast cancer cells by stabilizing tubulin and arresting the cells in the G₂/M phase. We determined the maximum tolerated dose (MTD) and systemic and vital organ toxicity of LCA-DTX-PEG NMs in mice, rats, and rabbits. LCA-DTX-PEG NMs showed a MTD of >160 mg kg^-1 and are found to be safe in comparison with their parent FDA-approved drug formulation (Taxotere® or DTX-TS) that is highly toxic. LCA-DTX-PEG NMs effectively reduced the tumor volume and increased the survival of 4T1 tumor-bearing mice with improved blood circulation time of the drug and its higher accumulation in tumor tissues. Therefore, this study highlights the potential of PEGylated bile acid-drug conjugate based nanomicelles for the development of next generation cancer therapeutics.

Emerging nanotaxanes for cancer therapy

The clinical application of taxane (including paclitaxel, docetaxel, and cabazitaxel)-based formulations is significantly impeded by their off-target distribution, unsatisfactory release, and acquired resistance/metastasis. Recent decades have witnessed a dramatic progress in the development of high-efficiency, low-toxicity nanotaxanes via the use of novel biomaterials and nanoparticulate drug delivery systems (nano-DDSs). Thus, in this review, the achievements of nanotaxanes-targeted delivery and stimuli-responsive nano-DDSs-in preclinical or clinical trials have been outlined. Then, emerging nanotherapeutics against tumor resistance and metastasis have been overviewed, with a particular emphasis on synergistic therapy strategies (e.g., combination with surgery, chemotherapy, radiotherapy, biotherapy, immunotherapy, gas therapy, phototherapy, and multitherapy). Finally, the latest oral nanotaxanes have been briefly discussed.

Albumin-bound paclitaxel and gemcitabine combination therapy in soft tissue sarcoma

BACKGROUND

The evidence that albumin-bound paclitaxel (nab-paclitaxel) is safe and efficacious for the treatment of many types of malignant tumors is continuously increasing. However, the evidence and clinical data of nab-paclitaxel and gemcitabine in metastatic soft tissue sarcoma (STS) treatment are rare.

METHODS

The clinical data of metastatic STS patients who received nab-paclitaxel/ gemcitabine chemotherapy between January 2019 and February 2020 were retrospectively analysed. All these patients were treated with nab-paclitaxel/ gemcitabine only after doxorubicin-based chemotherapy had failed. We evaluated the effectiveness and safety of nab-paclitaxel and gemcitabine in these patients.

RESULTS

A total of 17 patients treated with nab-paclitaxel/ gemcitabine were enrolled in this study. One patient with angiosarcoma achieved complete response, 6 patients had partial response, 5 patients achieved stable disease, and 5 patients had progressive disease. The average diameter change in target lesion from baseline was - 19.06 ± 45.74%. And median progression free survival was 6 months (95% CI, 2-9 months). Grade 3 / 4 adverse events were not common, included neutropenia (17.6%), fatigue (11.8%), anemia (11.8%), leukopenia (11.8%), nausea (5.9%), peripheral neuropathy (5.9%), diarrhea (5.9%), and thrombocytopenia (5.9%). No treatment-related deaths occurred.

CONCLUSION

Nab-paclitaxel/ gemcitabine combination chemotherapy is comparatively effective in the treatment of STS, demonstrates low toxicity, and is worthy of further study.

Nanomedicine-mediated alteration of the pharmacokinetic profile of small molecule cancer immunotherapeutics

The advent of immunotherapy is a game changer in cancer therapy with monoclonal antibody- and T cell-based therapeutics being the current flagships. Small molecule immunotherapeutics might offer advantages over the biological drugs in terms of complexity, tissue penetration, manufacturing cost, stability, and shelf life. However, small molecule drugs are prone to rapid systemic distribution, which might induce severe off-target side effects. Nanotechnology could aid in the formulation of the drug molecules to improve their delivery to specific immune cell subsets. In this review we summarize the current efforts in changing the pharmacokinetic profile of small molecule immunotherapeutics with a strong focus on Toll-like receptor agonists. In addition, we give our vision on limitations and future pathways in the route of nanomedicine to the clinical practice.

α3β1 Integrin-Targeting Polymersomal Docetaxel as an Advanced Nanotherapeutic for Nonsmall Cell Lung Cancer Treatment

Docetaxel (DTX) widely used for treating nonsmall cell lung cancer (NSCLC) patients is associated with dose-limiting side effects, especially neurotoxicity and myelosuppression. Here, we have developed cyclic cNGQGEQc peptide-directed polymersomal docetaxel (cNGQ-PS-DTX) as a targeted and multifunctional formulation for NSCLC. cNGQ-PS-DTX carrying 8.1 wt % DTX had a size of 93 nm, neutral surface charge, high stability, and glutathione-triggered DTX release behavior. Cytotoxicity studies demonstrated a clearly better antitumor activity of cNGQ-PS-DTX in α3β1 integrin overexpressing A549 human lung cancer cells than free DTX and nontargeted PS-DTX. cNGQ-PS-DTX showed a remarkably high tolerability (over 8 times better than free DTX) and slow elimination in mice. Importantly, cNGQ-PS-DTX exhibited greatly improved tumor accumulation and higher suppression of subcutaneous and orthotopic A549 xenografts as compared to PS-DTX and free DTX controls. α3β1 integrin-targeting polymersomal docetaxel emerges as an advanced nanotherapeutic for NSCLC treatment.

Amphiphilic Copolymer of Polyhedral Oligomeric Silsesquioxane (POSS) Methacrylate for Solid Dispersion of Paclitaxel

Suitable polymers for the homogeneous formulation of drug/polymer mixtures should be selected to correct the structural and physicochemical nature with a rapid dissolution rate. This study aimed to evaluate a copolymer prepared by the radical polymerization of 2-methacryloyloxyethyl phosphorylcholine (MPC) and a polyhedral oligomeric silsesquioxane (POSS) methacrylate bearing an ethyl (C₂H₅) group (MPC-ran-C₂H₅-POSS) as a carrier for the solid formulation of paclitaxel (PTX). A single-phase homogeneous formulation of PTX with the mixture of the MPC-ran-C₂H₅-POSS and polyvinylpyrrolidone (PVP) was prepared by a solvent method. The formulation of MPC-ran-C₂H₅-POSS/PVP/PTX enhanced the dissolution rate and the dissolved amount (approximately 90% within 40 min) without precipitation. The X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and differential scanning calorimetry (DSC) analysis confirmed the presence of PTX as an amorphous state. The amphiphilic nature of the MPC-ran-C₂H₅-POSS contributed to enhancing the aqueous solubility of PTX. The new formulation is applicable for solid dispersion technique via the supersaturation of PTX in an aqueous media.

Current advances in development of new docetaxel formulations

INTRODUCTION

Docetaxel (DTX) is one of the most important chemotherapeutic agents and has been widely used for treatment of various types of cancers. However, the clinical chemotherapy of DTX gives many undesirable side effects due to the usage of organic solvent in the injection and its low selectivity for tumor cells. With the evolution of pharmaceutical technologies, great efforts have been paid to develop new DTX formulations to overcome these problems.

AREAS COVERED

This review provided an overview of the preparation and activities of new DTX formulations, which were classified by administration methods, including injection, oral, transdermal and rectal administration. Besides, up to date information of the clinical status of new DTX formulations was summarized. We also discussed the challenges and perspectives of the future development of DTX formulations.

EXPERT OPINION

There have been numerous studies on new DTX-based formulations in recent years, and many of them exhibited significantly enhanced anti-tumor and targeting activity compared with DTX in preclinical studies. However, only a few entered clinical trials, and none has been approved into market. The clinical translation of experimental drug faces many hurdles, including the limited knowledge of nanomedicine and oncology, safety issues, controllable and reproducible production.

Amino modified metal-organic frameworks as pH-responsive nanoplatforms for safe delivery of camptothecin

MIL-100(Fe) and MIL-101(Fe) metal-organic frameworks (MOFs) are excellent vehicles for drug delivery systems (DDSs) due to their high biocompatibility and stability in physiological fluids, as well as their pore diameter in the mesoporous range. Although they are appropriate for the internal diffusion of 20-(S)-camptothecin (CPT), a strongly cytotoxic molecule with excellent antitumor activity, no stable delivery system has been proposed so far for this drug based in MOFs. We here present novel DDSs based in amine functionalized MIL-100(Fe) and MIL-101(Fe) nanoMOFs with covalently bonded CPT. These CPT nanoplatforms are able to incorporate almost 20% of this molecule and show high stability at physiological pH, with no non-specific release. Based on their surface charge, some of these CPT loaded nanoMOFs present improved cell internalization in in vitro experiments. Moreover, a strong response to acid pH is observed, with up to four fold drug discharge at pH 5, which boost intracellular release by endosomolytic activity. These novel DDSs will help to achieve safe delivery of the very cytotoxic CPT, allowing to reduce the therapeutic dose and minimizing drug secondary effects.

A novel nanoformulation of PLGA with high non-ionic surfactant content improves in vitro and in vivo PTX activity against lung cancer

Paclitaxel (PTX), a chemotherapy agent widely used to treat lung cancer, is characterised by high toxicity, low bioavailability and the need to use of excipients with serious side effects that limit its use. Paclitaxel encapsulation into nanoparticles (NPs) generates drug pharmacokinetic and pharmacodynamic advantages compared to free PTX. In this context, a NP carrier formed from a copolymer of lactic acid and glycolic acid (PLGA) has demonstrated high biocompatibility and low toxicity and therefore being approved by FDA to be used in humans. We synthesised a new PLGA NP and loaded it with PTX to improve drug efficacy and reduce side effects. This nanoformulation showed biocompatibility and no toxicity to human immune system. These NPs favor the intracellular uptake of PTX and enhance its antitumor effect in human and murine lung cancer cells, with up to 3.6-fold reductions in the PTX's IC₅₀. Although PLGA NPs did not show any inhibitory capacity against P-glycoprotein, they increased the antitumor activity of PTX in cancer stem cells. Treatment with PLGA-PTX NPs increased apoptosis and significantly reduced the volume of the tumorspheres derived from A549 and LL2 cells by up to 36% and 46.5%, respectively. Biodistribution studies with PLGA-PTX NPs revealed an increase in drug circulation time, as well as a greater accumulation in lung and brain tissues compared to free PTX. Low levels of PTX were detected in the dorsal root ganglion with PLGA-PTX NPs, which could exert a protective effect against peripheral neuropathy. In vivo treatment with PLGA-PTX NPs showed a greater decrease in tumor volume (44.6%) in immunocompetent mice compared to free PTX (24.4%) and without increasing the toxicity of the drug. These promising results suggest that developed nanosystem provide a potential strategy for improving the chemotherapeutic effect and reducing the side effects of PTX.

A cabazitaxel liposome for increased solubility, enhanced antitumor effect and reduced systemic toxicity

The potential side effects of cabazitaxel (CBZ) in the field of cancer treatment have become a great limitation to its further clinical application. Liposomal delivery is a well-established approach to increase the therapeutic index of hydrophobic drugs. In this study, a PEG-modified liposome was developed for efficiently encapsulating CBZ, thus enhancing its specific tumor inhibition effect and reducing the systemic toxicity. It was found that the loading efficiency of CBZ into the liposome could be improved with the increase of lipophilic materials, as it could be over 80% under the weight ratio of 20:1 (total lipid: CBZ). The diameter of CBZ loaded liposome (CBZ@Lipo) was ∼100 nm. And the liposome suspending in aqueous medium was stable at 4 °C for at least one month, according to the change of its size distribution. The killing ability of CBZ@Lipo to cancer cells was significantly lower comparing to that of CBZ solution, which could be attributed to the slow release of CBZ from the liposomes. However, CBZ@Lipo could induce an obvious apoptosis of the cancer cells at low concentration. Furthermore, CBZ@Lipo exhibited an expressively enhanced tumor growth inhibition effect comparing to CBZ solution. More importantly, CBZ@Lipo showed an obviously higher biosafety proved by lower hemolysis probability, stable body weight of mice during the whole experiment and no obvious lesion in histology analysis. Our work provided a useful reference of the formulation of CBZ, which had potential for greater clinical application.

Imidazole-Bearing Polymeric Micelles for Enhanced Cellular Uptake, Rapid Endosomal Escape, and On-demand Cargo Release

The complex design of multifunctional nanomedicine is beneficial to overcome the multiple biological barriers of drug delivery, but it also presents additional hurdles to clinical translation (e.g., scaling-up and quality control). To address this dilemma, we employed a simple imidazole-bearing polymer micelle for enhanced cellular uptake, facilitated endosomal escape, and on-demand release of a model drug, SN-38. The micelles were crosslinked by the reversible imidazole/Zn²⁺ coordination with a drug loading of ca. 4% (w/w) and a diameter less than 200 nm. Under mimicked tumor microenvironment (pH 6.8), the surface charge of micelles reversed from negative to positive, leading to enhanced micelles uptake by model 4T1 cells. Such effect was verified by fluorescent labelling of micelles. Compared to imidazole-free nanocarriers, the charge-reversal micelles delivered significantly more SN-38 to 4T1 cells. Due to the proton sponge effect, imidazole-bearing micelles could rapidly escape from endosomes compared to the control micelles, as evidenced by the kinetic analysis of micelle/endosome co-localization. The coordination crosslinking also enabled the acid-triggered drug release. This work provides a "three birds with one stone" approach to achieve the multifunctionality of nanocarriers without complicated particle design, and opens new avenues of advancing nanomedicine translation via simple tailored nanocarriers.

Enhanced anti-hepatocarcinoma efficacy by GLUT1 targeting and cellular microenvironment-responsive PAMAM-camptothecin conjugate

The efficient targeting of drugs to tumor cell and subsequent rapid drug release remain primary challenges in the development of nanomedicines for cancer therapy. Here, we constructed a glucose transporter 1 (GLUT1)-targeting and tumor cell microenvironment-sensitive drug release Glucose–PEG–PAMAM-s-s–Camptothecin-Cy7 (GPCC) conjugate to tackle the dilemma. The conjugate was characterized by a small particle size, spherical shape, and glutathione (GSH)-sensitive drug release. In vitro tumor targeting was explored in monolayer (2D) and multilayer tumor spheroid (3D) HepG2 cancer cell models (GLUT1⁺). The cellular uptake of GPCC was higher than that in the control groups and that in normal L02 cells (GLUT1⁻), likely due to the conjugated glucose moiety. Moreover, the GPCC conjugate exhibited stronger cytotoxicity, higher S arrest and enhanced apoptosis and necrosis rate in HepG2 cells than control groups but not L02 cells. However, the cytotoxicity of GPCC was lower than that of free CPT, which could be explained by the slower release of CPT from the GPCC compared with free CPT. Additional in vivo tumor targeting experiments demonstrated the superior tumor-targeting ability of the GPCC conjugate, which significantly accumulated in tumor meanwhile minimize in normal tissues compared with control groups. The GPCC conjugate showed better pharmacokinetic properties, enabling a prolonged circulation time and increased camptothecin area under the curve (AUC). These features contributed to better therapeutic efficacy and lower toxicity in H22 hepatocarcinoma tumor-bearing mice. The GLUT1-targeting, GSH-sensitive GPCC conjugate provides an efficient, safe and economic approach for tumor cell targeted drug delivery.

Overcoming Multidrug Resistance through the GLUT1-Mediated and Enzyme-Triggered Mitochondrial Targeting Conjugate with Redox-Sensitive Paclitaxel Release

Multidrug resistance (MDR) is thought to be the major obstacle leading to the failure of paclitaxel (PTX) chemotherapy. To solve this problem, a glucose transporter-mediated and matrix metalloproteinase 2 (MMP2)-triggered mitochondrion-targeting conjugate [glucose-polyethylene glycol (PEG)-peptide-triphenylphosponium-polyamidoamine (PAMAM)-PTX] composed of a PAMAM dendrimer and enzymatic detachable glucose-PEG was constructed for mitochondrial delivery of PTX. The conjugate was characterized by a 30 nm sphere particle, MMP2-sensitive PEG outer layer detachment from PAMAM, and glutathione (GSH)-sensitive PTX release. It showed higher cellular uptake both in glucose transporter 1 (GLUT1) overexpressing MCF-7/MDR monolayer cell (2D) and multicellular tumor spheroids (3D). The subcellular location study showed that it could specifically accumulate in the mitochondria. Moreover, it exhibited higher cytotoxicity against MCF-7/MDR cells, which significantly reverse the MDR of MCF-7/MDR cells. The MDR reverse might be caused by reducing the ATP content through destroying the mitochondrial membrane as well as by down-regulating P-gp expression. In vivo imaging and tissue distribution indicated more conjugate accumulated in the tumor of the tumor-bearing mice model. Consequently, the conjugate showed better tumor inhibition rate and lower body weight loss, which demonstrated that it possessed high efficiency and low toxicity. This study provides glucose-mediated GLUT targeting, MMP2-responsive PEG detachment, triphenylphosponium-mediated mitochondria targeting, and a GSH-sensitive intracellular drug release conjugate that has the potential to be exploited for overcoming MDR of PTX.

Integrated Multifunctional Micelles Co-Self-Assembled from Polypeptides Conjugated with Natural Ferulic Acid and Lipoic Acid for Doxorubicin Delivery

The development of safe, easily accessible, and multifunctional nanocarriers is a big topic in nanomedicine research. Here, integrated multifunctional micelles (IMM) were developed by co-self-assembly of poly(ethylene glycol)-b-poly(l-lysine) derivatives with natural ferulic acid (FA) or lipoic acid (LA). FA confers IMM with intrinsic antitumor activity, improved loading of doxorubicin (DOX) through π-π stacking, and reduced DOX cardiotoxicity. LA provides IMM with reversible crosslinking property, which leads to a high colloidal stability with inhibited drug leakage and triggered intracellular DOX release. Notably, our results showed that cRGD-decorated IMM (cRGD-IMM) had a small size (≈56 nm) and superior loading of DOX (27.1 wt. %). Blank cRGD-IMM, though nontoxic to normal cells, exhibited obvious antiproliferative activity against cancer cells including B16F10 and HCT-116 cells at 150 μg FA equiv. mL^-1 . DOX-loaded cRGD-IMM displayed enhanced growth inhibition of α_v β₃ -positive B16F10 and HCT-116 cells, a long elimination half-life of 3.85 h, and a high maximum-tolerated dose of over 100 mg DOX equiv. kg^-1 . Histological analysis revealed that DOX-loaded cRGD-IMM at 100 mg DOX equiv. kg^-1 caused negligible cardiotoxicity, which is a major issue for the clinical use of DOX. These integrated multifunctional micelles with excellent safety and accessibility have emerged as a new platform for targeted cancer chemotherapy.

Self-stabilized, hydrophobic or PEGylated paclitaxel polymer prodrug nanoparticles for cancer therapy

Facile derivatization of paclitaxel (Ptx) and subsequent “drug-initiated” synthesis of well-defined Ptx-polymer prodrugs was performed from nitroxide-mediated polymerization or reversible addition–fragmentation chain transfer polymerization.

Deguelin, an Aurora B Kinase Inhibitor, Exhibits Potent Anti-Tumor Effect in Human Esophageal Squamous Cell Carcinoma

Aurora B kinase has emerged as a key regulator of mitosis and deregulation of Aurora B activity is closely related to the development and progression of human cancers. In the present study, we found that Aurora B is overexpressed in human esophageal squamous cell carcinoma (ESCC), high levels of Aurora B protein were associated with a worse overall survival rate in ESCC patients. Depleting of Aurora B blunted the malignant phenotypes in ESCC cells. Importantly, we demonstrated that a natural compound, deguelin, has a profound anti-tumor effect on ESCC via inhibiting Aurora B activity. Deguelin potently inhibited in vitro Aurora B kinase activity. The in silico docking study further indicated that deguelin was docked into the ATP-binding pocket of Aurora B. Inhibition of Aurora B activity attenuated growth of ESCC cells, resulted in G2/M cell cycle arrest, polyploidy cells formation, and apoptosis induction. Knocking down of Aurora B decreased the sensitivity of ESCC cells to deguelin. The in vivo results showed that deguelin blocked the phosphorylation of histone H3 and inhibited the growth of ESCC tumor xenografts. Overall, we identified deguelin as an effective Aurora B inhibitor, which deserves further studies in other animal models and ESCC treatment.