Anti-EGFR immunoliposomes for cabazitaxel delivery: From formulation development to in vivo evaluation in prostate cancer xenograft model.

Liposomes functionalized with monoclonal antibodies offer targeted therapy for cancer, boasting advantages like sustained drug release, enhanced stability, passive accumulation in tumors, and interaction with overexpressed receptors on cancer cells. This study aimed to develop and characterize anti-EGFR immunoliposomes loaded with cabazitaxel and assess their properties against prostate cancer in vitro and in vivo. Using a Box-Behnken design, a formulation with soy phosphatidylcholine, 10% cholesterol, and a 1:20 drug-lipid ratio yielded nanometric particle size, low polydispersity and high drug encapsulation. Immunoliposomes were conjugated with cetuximab through DSPE-PEG-Maleimide lipid anchor. Characterization confirmed intact antibody structure and interaction with EGFR receptor following conjugation. Cabazitaxel was dispersed within the liposomes in the amorphous state, confirmed by solid-state analyses. In vitro release studies showed slower cabazitaxel release from immunoliposomes. Immunoliposomes had enhanced cabazitaxel cytotoxicity in EGFR-overexpressing DU145 cells without affecting non-tumor L929 cells. Cetuximab played an important role to improve cellular uptake in a time-dependent fashion in EGFR-overexpressing prostate cancer cells. In vivo, immunoliposomes led to significant tumor regression, improved survival, and reduced weight loss in xenograft mice. While cabazitaxel induced leukopenia, consistent with clinical findings, histological analysis revealed no evident toxicity. In conclusion, the immunoliposomes displayed suitable physicochemical properties for cabazitaxel delivery, exhibited cytotoxicity against EGFR-expressing prostate cancer cells, with high cell uptake, and induced significant tumor regression in vivo, with manageable systemic toxicity.

Crafting Docetaxel-Loaded Albumin Nanoparticles Through a Novel Thermal-Driven Self-Assembly/Microfluidic Combination Technology: Formulation, Process Optimization, Stability, and Bioavailability.

Background: The commercial docetaxel (DTX) formulation causes severe side effects due to polysorbate 80 and ethanol. Novel surfactant-free nanoparticle (NP) systems are needed to improve bioavailability and reduce side effects. However, controlling the particle size and stability of NPs and improving the batch-to-batch variation are the major challenges. Methods: DTX-loaded bovine serum albumin nanoparticles (DTX-BSA-NPs) were prepared by a novel thermal-driven self-assembly/microfluidic technology. Single-factor analysis and orthogonal test were conducted to obtain the optimal formulation of DTX-BSA-NPs in terms of particle size, encapsulation efficiency (EE), and drug loading (DL). The effects of oil/water flow rate and pump pressure on the particle size, EE, and DL were investigated to optimize the preparation process of DTX-BSA-NPs. The drug release, physicochemical properties, stability, and pharmacokinetics of NPs were evaluated. Results: The optimized DTX-BSA-NPs were uniform, with a particle size of 118.30 nm, EE of 89.04%, and DL of 8.27%. They showed a sustained release of 70% over 96 hours and an increased stability. There were some interactions between the drug and excipients in DTX-BSA-NPs. The half-life, mean residence time, and area under the curve (AUC) of DTX-BSA-NPs increased, but plasma clearance decreased when compared with DTX. Conclusion: The thermal-driven self-assembly/microfluidic combination method effectively produces BSA-based NPs that improve the bioavailability and stability of DTX, offering a promising alternative to traditional formulations.

Effect of substituents at the C3´, C3´N, C10 and C2-meta-benzoate positions of taxane derivatives on their activity against resistant cancer cells.

We tested the effect of substituents at the (1) C3´, C3´N, (2) C10, and (3) C2-meta-benzoate positions of taxane derivatives on their activity against sensitive versus counterpart paclitaxel-resistant breast (MCF-7) and ovarian (SK-OV-3) cancer cells. We found that (1) non-aromatic groups at both C3´ and C3´N positions, when compared with phenyl groups at the same positions of a taxane derivative, significantly reduced the resistance of ABCB1 expressing MCF-7/PacR and SK-OV-3/PacR cancer cells. This is, at least in the case of the SB-T-1216 series, accompanied by an ineffective decrease of intracellular levels in MCF-7/PacR cells. The low binding affinity of SB-T-1216 in the ABCB1 binding cavity can elucidate these effects. (2) Cyclopropanecarbonyl group at the C10 position, when compared with the H atom, seems to increase the potency and capability of the derivative in overcoming paclitaxel resistance in both models. (3) Derivatives with fluorine and methyl substituents at the C2-meta-benzoate position were variously potent against sensitive and resistant cancer cells. All C2 derivatives were less capable of overcoming acquired resistance to paclitaxel in vitro than non-substituted analogs. Notably, fluorine derivatives SB-T-121205 and 121,206 were more potent against sensitive and resistant SK-OV-3 cells, and derivatives SB-T-121405 and 121,406 were more potent against sensitive and resistant MCF-7 cells. (4) The various structure-activity relationships of SB-T derivatives observed in two cell line models known to express ABCB1 favor their complex interaction not based solely on ABCB1.

Functionalized nano cellulose double-template imprinted aerogel microsphere for the targeted enrichment of taxanes.

Paclitaxel, a diterpenoid isolated from the bark of Taxus wallichiana var. chinensis (Pilger) Florin, is currently showing significant therapeutic effects against a variety of cancers. Baccatin III (Bac) and 10-Deacetylbaccatin III (10-DAB) are in great demand as important precursors for the synthesis of paclitaxel. This work aims to develop a simple, rapid and highly selective, safe, and non-polluting molecularly imprinted material for 10-DAB and Bac enrichment. In this study, we innovatively prepared molecularly imprinted materials with nanocellulose aerogel microspheres and 2-vinylpyridine (2-VP) as a bifunctional monomer, and 10-DAB and Bac as bis-template molecules. In particular, functionalized nanocellulose dual-template molecularly imprinted aerogel microsphere (FNCAG-DMIM) were successfully synthesized by the bifunctional introduction of functional nanocellulose aerogel microsphere (FNCAG) modified with Polyethyleneimine (PEI) as a carrier and functional monomer, which provided a large number of recognition sites for bimodal molecules. FNCAG-DMIM showed high specificity for 10-DAB and Bac specific assays. Under the optimal experimental conditions, the adsorption capacities of FNCAG-DMIM for 10-DAB and Bac reached 52.27 mg g-1 and 53.81 mg g-1, respectively. In addition, it showed good reliability and practicality in the determination of real samples. The present study extends the research on the synthesis of natural functional monomers by molecularly imprinted materials and opens up new horizons for the targeted isolation of plant compounds by dual-template molecularly imprinted materials.

The cytotoxic natural compound erianin binds to colchicine site of ß-tubulin and overcomes taxane resistance.

Erianin, a natural compound derived from Dendrobium, has shown significant anticancer properties against a wide range of cancer cells. Despite the identification of multiple mechanisms of action for erianin, none of these mechanisms fully account for its broad-spectrum effect. In this study, we aimed to identify the cellular target and underlying mechanism responsible for the broad-spectrum antitumor effects of erianin. We found that erianin effectively inhibited tubulin polymerization in cancer cells and purified tubulin. Through competition binding assays and X-ray crystallography, it was revealed that erianin bound to the colchicine site of ß-tubulin. Importantly, the X-ray crystal structure of the tubulin-erianin complex was solved, providing clear insight into the orientation and position of erianin in the colchicine-binding site. Erianin showed activity against paclitaxel-resistant cells, evidenced by G2/M cell cycle arrest, apoptosis-related PARP and Caspase-3 cleavage, and in vivo xenograft studies. The study concluded that erianin bound reversibly to the colchicine site of ß-tubulin, inhibited tubulin polymerization, and displayed anticancer activity against paclitaxel-resistant cells, offering valuable insights for further exploration as potential anticancer agents.

A general strategy for the synthesis of taxane diterpenes.

The carbon skeleton of any organic molecule serves as the foundation for its three-dimensional structure, playing a pivotal role in determining its physical and biological properties1. As such, taxane diterpenes are one of the most well-known natural product families, primarily owing to the success of their most prominent compound, paclitaxel, an effective anticancer therapeutic for more than 25 years2-6. In contrast to classical taxanes, the bioactivity of cyclotaxanes (also referred to as complex taxanes) remains significantly underexplored. The carbon skeletons of these two groups of taxanes differ significantly, and so would typically their own distinct synthetic approaches. Here we report a versatile synthetic strategy based on the interconversion of complex molecular frameworks, providing general access to the wider taxane diterpene family. A range of classical and cyclotaxane frameworks was prepared including, among others, the total syntheses of taxinine K (2), canataxapropellane (5) and dipropellane C from a single advanced intermediate. The synthetic approach deliberately eschews biomimicry, emphasizing instead the power of stereoelectronic control in orchestrating the interconversion of polycyclic frameworks.

Comparative evaluation of liquid-liquid extraction and nanosorbent extraction for HPLC-PDA analysis of cabazitaxel from rat plasma.

A precise, sensitive, accurate, and validated reverse-phase high-performance liquid chromatography (RP-HPLC) method with a bioanalytical approach was utilized to analyze Cabazitaxel (CBZ) in rat plasma. Comparative research on extraction recoveries was performed between traditional liquid-liquid extraction (LLE) and synthesized graphene oxide (GO) based magnetic solid phase extraction (GO@MSPE). The superparamagnetic hybrid nanosorbent was synthesized using the combination of iron oxide and GO and subsequently applied for extraction and bioanalytical quantification of CBZ from plasma by (HPLC-PDA) analysis. Fourier- transform infrared spectroscopy (FT-IR), particle size, scanning electron microscopy (SEM), and x-ray diffraction (XRD) analysis were employed in the characterization of synthesized GO@MSPE nanosorbent. The investigation was accomplished using a shim pack C18 column (150 mm×4.6 mm, 5 µm) with a binary gradient mobile phase consisting of formic acid: acetonitrile: water (0.1:75:25, v/v/v) at a 0.8 mL/min flow rate, and a λmax of 229 nm. The limits of detection (LOD) and quantitation (LOQ) have been determined to be 50 and 100 ng/mL for both LLE and SPE techniques. The linearity range of the approach encompassed from 100 to 5000 ng/mL and was found to be linear (coefficient of determination > 0.99) for CBZ. The proposed method showed extraction recovery of 76.8-88.4% for the synthesized GO@MSPE and 69.3-77.4% for LLE, suggesting that the proposed bioanalytical approach was robust and qualified for all validation parameters within the acceptable criteria. Furthermore, the developed hybrid GO@MSPE nanosorbent with the help of the proposed RP-HPLC method, showed a significant potential for the extraction of CBZ in bioanalysis.

The Investigation of the Subtle Structural Discrepancies between Oryza Sativa Recombinant and Plasma-Derived Human Serum Albumins to Design a Novel Nanoparticle as a Taxane Delivery System.

To solve the large size faultiness of Oryza sativa recombinant human serum albumin nanoparticle (OsrHSA NP), the structural discrepancies between OsrHSA and plasma-derived human serum albumin (pdHSA) were analyzed deeply in this research. It demonstrated that there were some subtle structural discrepancies located in subdomain IA and IIA between OsrHSA and pdHSA, which included peptide backbone, disulphide bridge and some amino acids. Firstly, the structural discrepancies were investigated through literature comparison, it inferred that the structural discrepancies resulted from the fatty acid (FA) binding to OsrHSA at site 2 of subdomain IA and IIA. To form a cavity for accommodation of FA molecule in OsrHSA, the peptide backbone structure of subdomain IA and IIA would change, accompanied by the conformational transition of disulphide bridges and side chain structure change of some amino acids in subdomain IA and IIA. These alterations induced the exposure of tryptophan (Trp) and tyrosine (Tyr) residues in subdomain IA and IIA and the decrease of net negative charges of molecular surface. The former would promote more OsrHSA molecules aggregate, and the latter would weaken the electrostatic repulsion. As a result, the size of OsrHSA NP was more extensive than that of pdHSA NP (175.84 ± 15.63 nm vs. 31.67 ± 1.31 nm) when the concentration of Dimethyl Sulphoxide (DMSO) was 30% (v/v). In this study, the experimental scheme of OsrHSA NP preparation was improved. There were two changes in the enhanced preparation scheme: pH 8.2 PBS buffer and 63% DMSO. It indicated that the improved OsrHSA NP carrier was comparable to the pdHSA NP carrier. The size and drug loading of paclitaxel-loaded improved OsrHSA NP were 53.57 ± 3.63 nm and 7.25 ± 0.46% (w/w), and those of docetaxel-loaded improved OsrHSA NP were 44.75 ± 2.26 nm and 8.43 ± 0.74% (w/w). Moreover, both NPs exhibited good stability for 168 h at 7.4 pH values. It is established that the improved OsrHSA NP is comparable to the pdHSA NP as a taxane delivery system.

Synthesis and in vitro antitumor activity of galactosamine-docetaxel conjugates.

Docetaxel (DTX) is a semi-synthetic analogue of paclitaxel which has attracted extensive attention in the treatment of cancer. However, the current clinically used DTX formulations display low tumor targeting ability, leading to unsatisfactory therapeutic outcomes with adverse effects, which poses significant challenges to the clinical application. In this study, three galactosamine (Gal) and docetaxel conjugates with different linkers were synthesized, namely DTX-(suc-Gal)2, DTX-(DTDPA-Gal)2, and DTX-(DSeDPA-Gal)2. These three conjugates were characterized by 1H NMR, FT-IR and HRMS. The in vitro drug release study shows that DTX-(DTDPA-Gal)2 and DTX-(DSeDPA-Gal)2 exhibit glutathione (GSH)-responsive drug release and DTX-(DSeDPA-Gal)2 displays higher GSH-responsiveness. The in vitro antitumor activity study shows that DTX-(DTDPA-Gal)2 and DTX-(DSeDPA-Gal)2 exhibit enhanced cytotoxicity, cell apoptosis rate and G2/M phase arrest against HepG2 cells as compared to DTX-(suc-Gal)2, DTX-(DSeDPA-Gal)2 displays the highest cytotoxicity, cell apoptosis rate and G2/M phase arrest among these three conjugates. In addition, DTX-(DSeDPA-Gal)2 exhibits higher selectivity to HepG2 cells as compared to free DTX. The DTX-(DSeDPA-Gal)2 developed in this study has been proven to be an effective DTX conjugate for selective killing hepatoma cells.