Paclitaxel-loaded Nanoparticles Research Articles

Magnetic precision: Unleashing the therapeutic potential of paclitaxel-loaded nanoparticles in breast cancer treatment

Breast cancer remains a formidable global health challenge, necessitating innovative therapeutic strategies. In this context, our investigation delves into the potential of paclitaxel-loaded magnetic nanoparticles (MNPs) as a targeted and effective therapeutic approach for breast cancer. With its high incidence and significant impact on morbidity and mortality, breast cancer necessitates novel treatment modalities to enhance therapeutic outcomes and mitigate systemic toxicity associated with conventional chemotherapeutic agents. This study employs a comprehensive methodology encompassing various in vitro characterizations, cytotoxicity assessments, cellular uptake studies, in vivo experiments, and pharmacokinetic analyses to systematically evaluate the efficacy of paclitaxel-loaded MNPs. Our findings reveal that paclitaxel-loaded MNPs exhibit superior cytotoxicity, enhanced cellular uptake, and the induction of apoptosis compared to free paclitaxel. In vivo investigations further demonstrate notable tumor shrinkage and improved hematological parameters, indicating reduced systemic toxicity. However, pharmacokinetic evaluations underscore the need for refinement in this promising therapeutic approach. This research accentuates the potential of paclitaxel-loaded MNPs as a compelling candidate for breast cancer treatment, emphasizing the imperative for ongoing investigation and rigorous clinical validation. The integration of targeted nanocarrier systems into breast cancer therapy represents a promising avenue for advancing precision medicine and improving patient outcomes.

Abstract 5755: Development of paclitaxel-loaded nanoparticles with high charge density

Abstract Paclitaxel (PTX) is a potent anticancer agent with desirable efficacy against pancreatic cancer when used in conjunction with gemcitabine. The current formulation of nab-paclitaxel shows an improved safety profile compared to the conventional PTX, but the highly potent nature of paclitaxel still poses a problem as it leads to severe side effects, such as neutropenia and neuropathy, calling for the development of carriers with better targeting ability. Tumor treating fields (TTFields) is a new noninvasive treatment modality which disrupts the mitosis of a cell with alternating electric fields with low and intermediate frequency (100 - 500 kHz). Highly polar or charged macromolecules are impacted by the presence of TTFields as they lose random motions essential for mitosis. In previous work on the formulation of self-assembling cationic-anionic nanoparticles (S-CAP NPs), gemcitabine was successfully loaded into the nanoparticles with optimal particle size, stability, and release profile responsive to TTFields. In this study, S-CAP NPs were developed with biocompatible polymers, DEAE-dextran (Ddex) and bovine serum albumin (BSA), via a relatively green method to load paclitaxel with minimal use of organic solvents. Based on the previous study and the proof of concept, it can be hypothesized that the S-CAP NPs can successfully carry PTX and release it in the presence of TTFields. Various parameters, such as temperature, rpm, and concentration, were tested to optimize the size, PDI, zeta potential, and stability of the particles. The HPLC method was developed for PTX and used to analyze drug loading. Numerous compositions of BSA and Ddex were tested, and the ratio of 10:1 (BSA:Ddex) developed the best parameters of the S-CAP NPs. At 50 °C, the zeta potential of the particle was -3.55 ± 0.23 mV for the NPs, but the particles agglomerated over time as BSA precipitates were formed. At -15°C, the particle size was 302.9 ± 2.0 nm (PDI = 0.307 ± 0.038). Varying concentrations of BSA and Ddex showed the formation of S-CAP NPs at lower concentration. The optimal particle was formed at room temperature (RT) with BSA 0.1% and Ddex 0.01% with a size of 264.6 ± 19.7 nm (PDI = 0.079 ± 0.028) and a zeta potential of -14.67 ± 0.07 mV. The particles showed desirable stability for 48 hours. The HPLC analysis (Agilent, Phenomenex C18, 150 x 4.6 mm, 5 micron) was tested for validity and robustness (r2 = 0.9996). Currently, the drug loading was achieved at 1.9% and the optimization studies are ongoing. In vitro cell viability assay (MTS) with and without TTFields is under exploration. With the successful formulation of PTX-loaded S-CAP NPs, co-loading PTX and gemcitabine can be explored to reduce the treatment burden of the patients. Citation Format: Katherine Y. Bang, Preshita P. Desai. Development of paclitaxel-loaded nanoparticles with high charge density [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5755.

Decreased Lung Metastasis in Triple Negative Breast Cancer Following Locally Delivered Supratherapeutic Paclitaxel-Loaded Polyglycerol Carbonate Nanoparticle Therapy.

Breast cancer is among the most prevalent malignancies, accounting for 685,000 deaths worldwide in 2020, largely due to its high metastatic potential. Depending on the stage and tumor characteristics, treatment involves surgery, chemotherapy, targeted biologics, and/or radiation therapy. However, current treatments are insufficient for treating or preventing metastatic disease. Herein, we describe supratherapeutic paclitaxel-loaded nanoparticles (81 wt % paclitaxel) to treat the primary tumor and reduce the risk of subsequent metastatic lesions in the lungs. Primary tumor volume and lung metastasis are reduced by day 30, compared to the paclitaxel clinical standard treatment. The ultrahigh levels of paclitaxel afford an immunotherapeutic effect, increasing natural killer cell activation and decreasing NETosis in the lung, which limits the formation of metastatic lesions.

The influence of electron beam and gamma irradiation on paclitaxel-loaded nanoparticles of fully randomized copolymers in relation to potential sterilization

The presented report describes the evaluation of the influence of e-beam and γ-radiation on properties of the newly developed anticancer drug delivery systems (DDSs) based on biodegradable polymeric matrices: poly(ɛ-caprolactone) (PCL), poly(l-lactide) (PLA), poly(l-lactide-co-ɛ-caprolactone) (PLACL) and poly(ɛ-caprolactone-co-glycolide) (PCLGA), in relation to potential sterilization process. The physicochemical properties of the pharmaceutical formulations of paclitaxel (PTX)-loaded nanoparticles, as well as the basic polymeric matrices, were studied after irradiation with γ-rays and e-beam at sterilization dose 25 kGy. The structure of the polymers was found to be practically intact after the irradiation. Importantly, no PTX-related degradation products were detected after the irradiation. The results demonstrate, that the polyester based DDSs can realize sustained and controlled release of PTX. The kinetics of drug release were defined as first order with non-Fickian diffusion for all systems. The obtained results demonstrated a great potential of e-beam for the sterilization purposes of polymeric nanoparticles. In comparison, some effect on PTX release from the γ-irradiated copolymeric nanoparticles was observed due to faster polymer degradation.

Synthesis of Polyethylene Glycol-Poly(glycerol carbonate) Block Copolymeric Micelles as Surfactant-Free Drug Delivery Systems.

We report the synthesis of block copolymers of monomethoxylated polyethylene glycol and poly(glycerol carbonate) (mPEG-b-PGC) via the ring-opening polymerization of benzyl glycidyl ether, monomethoxylated polyethylene glycol, and carbon dioxide using a cobalt salen catalyst. The resulting block copolymers display high polymer/cyclic carbonate selectivity (>99%) and, if two oxirane monomers are used, random incorporation into the polymer feed. The resulting diblock mPEG-b-PGC polymer shows promise as a nanocarrier for surfactant-free, sustained chemotherapeutic delivery. mPEG-b-PGC, with paclitaxel conjugated to the pendant primary alcohol of the glycerol polymer backbone, readily forms 175 nm diameter particles in solution and contains 4.6 wt % paclitaxel (PTX), which is released over 42 days. The mPEG-b-PGC polymer itself is noncytotoxic, whereas the PTX-loaded nanoparticles are cytotoxic to lung, breast, and ovarian cancer cell lines.

Efficient pH-Responsive Nano-Drug Delivery System Based on Dynamic Boronic Acid/Ester Transformation.

Chemotherapy is currently one of the most widely used treatments for cancer. However, traditional chemotherapy drugs normally have poor tumor selectivity, leading to insufficient accumulation at the tumor site and high systemic cytotoxicity. To address this issue, we designed and prepared a boronic acid/ester-based pH-responsive nano-drug delivery system that targets the acidic microenvironment of tumors. We synthesized hydrophobic polyesters with multiple pendent phenylboronic acid groups (PBA-PAL) and hydrophilic PEGs terminated with dopamine (mPEG-DA). These two types of polymers formed amphiphilic structures through phenylboronic ester linkages, which self-assembled to form stable PTX-loaded nanoparticles (PTX/PBA NPs) using the nanoprecipitation method. The resulting PTX/PBA NPs demonstrated excellent drug encapsulation efficiency and pH-triggered drug-release capacity. In vitro and in vivo evaluations of the anticancer activity of PTX/PBA NPs showed that they improved the pharmacokinetics of drugs and exhibited high anticancer activity while with low systemic toxicity. This novel phenylboronic acid/ester-based pH-responsive nano-drug delivery system can enhance the therapeutic effect of anticancer drugs and may have high potential for clinical transformations.

Integrated multi-omics analysis reveals unique signatures of paclitaxel-loaded poly(lactide-co-glycolide) nanoparticles treatment of head and neck cancer cells.

The use of poly(lactide-co-glycolide) (PLGA) nanoparticles (NPs) as carriers for chemotherapeutic drugs is regarded as an actively targeted nano-therapy for the specific delivery of anti-cancer drugs to target cells. However, the exact mechanism by which PLGA NPs boost anticancer cytotoxicity at the molecular level remains largely unclear. This study employed different molecular approaches to define the response of carcinoma FaDu cells to different types of treatment, specifically: paclitaxel (PTX) alone, drug free PLGA NPs, and PTX-loaded PTX-PLGA NPs. Functional cell assays revealed that PTX-PLGA NPs treated cells had a higher level of apoptosis than PTX alone, whereas the complementary, UHPLC-MS/MS (TIMS-TOF) based multi-omics analyses revealed that PTX-PLGA NPs treatment resulted in increased abundance of proteins associated with tubulin, as well as metabolites such as 5-thymidylic acid, PC(18:1(9Z)/18:1(9Z0), vitamin D, and sphinganine among others. The multi-omics analyses revealed new insights about the molecular mechanisms underlying the action of novel anticancer NP therapies. In particular, PTX-loaded NPs appeared to exacerbate specific changes induced by both PLGA-NPs and PTX as a free drug. Hence, the PTX-PLGA NPs' molecular mode of action, seen in greater detail, depends on this synergy that ultimately accelerates the apoptotic process, resulting in cancer cell death.

Bacterial outer membrane vesicles-cloaked modified zein nanoparticles for oral delivery of paclitaxel

To improve the aqueous solubility and oral bioavailability of paclitaxel (PTX), a biomimetic system for oral administration of PTX was efficiently developed as an outer membrane vesicle (OMVs) of sodium caseinate (CAS) modified zein nanoparticles (OMVs-Zein-CAS-PTX-NPs) by Escherichia coli. To verify their structure and properties, the designed nanostructures were thoroughly characterized using various characterization techniques. The results indicated that hydrogen bonds and van der Waals forces mainly drove the interaction between PTX and Zein, but the complex is unstable. The physicochemical stability of PTX-loaded zein nanoparticles was improved by the addition of CAS. The biological characteristics of biofilms are reproduced by nanoparticles cloaked with outer membrane vesicles. OMVs-Zein-CAS-PTX-NPs delayed the release of PTX under simulated gastric and intestinal fluids due to OMVs protection. OMVs-Zein-CAS-PTX-NPs exhibited remarkable antitumor ability in vitro and improved the bioavailability of oral administration of PTX in vivo. Therefore, OMVs cloaked in nanoparticles may be a suitable delivery vehicle to provide an efficient application prospect for the oral administration of PTX.

Paclitaxel-loaded ROS-responsive nanoparticles for head and neck cancer therapy

High intracellular reactive oxygen species (ROS) level is characteristic of cancer cells and could act as a target for the efficient targeted drug delivery for cancer treatment. Consequently, biomaterials that react to excessive levels of ROS are essential for biomedical applications. In this study, a novel ROS-responsive polymer based on D-α-Tocopheryl polyethylene glycol 1000 succinate (TPGS) and poly (β-thioester) (TPGS-PBTE) was synthesized for targeted delivery of the first-line antineoplastic drug, paclitaxel (PTX). The resultant TPGS-PBTE NPs showed good ROS-responsive capability in size change and drug release. Compared to PTX, PTX-loaded nanoparticles (PTX@TPGS-PBTE NPs) showed enhanced cytotoxicity and higher level of apoptosis toward squamous cell carcinoma (SCC-7) cells. Tumor-targeted delivery of the NPs was also observed, especially after being modified with a tumor-targeting peptide, cRGD. Enhanced tumor growth inhibition was also observed in head and neck cancer SCC-7 murine models. In summary, PTX@TPGS-PBTE NPs can achieve good therapeutic effects of PTX against head and neck cancer both in vitro and in vivo, especially when modified by cRGD for active targeting, which enriched the application of ROS responsive system utilized in the delivery of anticancer drugs.

Exploring paclitaxel-loaded adenosine-conjugated PEGylated PLGA nanoparticles for targeting triple-negative breast cancer.

In present investigation, we developed paclitaxel (PTX)-loaded adenosine (ADN)-conjugated PLGA nanoparticles for combating triple-negative breast cancer (TNBC), where ADN acts as a substrate for adenosine receptors (AR) that are overexpressed in TNBC. Using synthesized PLGA-PEG-ADN, PTX-loaded nanoparticles (PTX ADN-PEG-PLGA NPs) were prepared via emulsion diffusion evaporation process that rendered particles of size 135 ± 12nm, PDI of 0.119 ± 0.03, and entrapment-efficiency of 79.26 ± 2.52%. The NPs showed higher %cumulative release at pH 5.5 over 7.4 with Higuchi release kinetics. The PTX ADN-PEG-PLGA NPs showed ~ 4.87- and 5.22-fold decrease in %hemolysis in comparison to free PTX and Intaxel®, indicating their hemocompatible nature. The ADN modification assisted cytoplasmic internalization of particles via AR-mediated endocytosis that resulted in ~ 3.77- and 3.51-fold reduction in IC50 and showed apoptosis index of 0.93 and 1.18 in MDA-MB-231 and 4T1 cells respectively. The pharmacokinetic profile of ADN-PEG-PLGA NPs revealed higher AUC and t1/2 than Intaxel® and Nanoxel®pharmacodynamic activity showed ~ 18.90-fold lower %tumor burden than control. The kidney and liver function biomarkers showed insignificant change in the levels, when treated with PTX ADN-PEG-PLGA NPs and exhibited no histological alterations in the liver, spleen, and kidney. Overall, the optimized particles were found to be biocompatible with improved anti-TNBC activity.

HA-PEG-PCL Nanoparticles With Paclitaxel Loaded For Targeted Delivery To Colon Cancer

For improved treatment efficacy with no or few adverse effects and higher patient compliance, novel delivery techniques with selective dispersion are required. The biodegradable and biocompatible polymers hyaluronic acid (HA), polyethylene glycol (PEG), and polycaprolactone (PCL) were used to create paclitaxel-loaded nanoparticles. The development and characterisation of a Paclitaxel-loaded HA-PEG-PCL polymeric nanoparticulate drug delivery system were the goals of the current study work in order to increase the therapeutic efficacy and targeted Paclitaxel distribution. The copolymers were chemically created, and IR spectroscopies were used to identify them. Transmission electron microscopy, particle size, percentage of drug entrapment, cell viability studies, stability, and in vitro drug release profile were used to describe the nanoparticles' structure and morphology. To determine whether PTX was crystalline or amorphous inside the polymer matrix, experiments using differential scanning calorimetry and X-ray diffraction were also carried out. Zeta potentials for blank NPs and PTX-HA-PEG-PCL NPs were respectively -15.4±1.23 mV and -18±2.35 mV. In 144 hours, PTX-HA-PEG-PCL NPs demonstrated a 58.08±3.8 release of PTX at pH 7.4. Because HA functions as a ligand for the CD44 receptors that are over expressed on HT-29 cells, the PTX-HA-PEG-PCL NPs demonstrated noticeably more cytotoxicity as a result of better formulation internalization. The proposed nanotechnology’s-controlled drug release behavior showed its potential for colon cancer cell lines

Branched Poly(ε-caprolactone)-Based Copolyesters of Different Architectures and Their Use in the Preparation of Anticancer Drug-Loaded Nanoparticles

Limitations associated with the use of linear biodegradable polyesters in the preparation of anticancer nano-based drug delivery systems (nanoDDS) have turned scientific attention to the utilization of branched-chain (co-)polymers. In this context, the present study evaluates the use of novel branched poly(ε-caprolactone) (PCL)-based copolymers of different architectures for the preparation of anticancer nanoparticle (NP)-based formulations, using paclitaxel (PTX) as a model drug. Specifically, three PCL-polyol branched polyesters, namely, a three-arm copolymer based on glycerol (PCL-GLY), a four-arm copolymer based on pentaerythritol (PCL-PE), and a five-arm copolymer based on xylitol (PCL-XYL), were synthesized via ring-opening polymerization and characterized by proton nuclear magnetic resonance (1H-NMR), gel permeation chromatography (GPC), intrinsic viscosity, differential scanning calorimetry (DSC), X-ray diffraction (XRD), and Fourier-transform infrared (FT-IR) spectroscopy and cytotoxicity. Then, PTX-loaded NPs were prepared by an oil-in-water emulsion. The size of the obtained NPs varied from 200 to 300 nm, while the drug was dispersed in crystalline form in all formulations. High encapsulation efficiency and high yields were obtained in all cases, while FTIR analysis showed no molecular drug polymer. Finally, in vitro drug release studies showed that the studied nanocarriers significantly enhanced the dissolution rate and extent of the drug.

Therapeutic Nanocarriers Inhibit Chemotherapy-Induced Breast Cancer Metastasis.

Chemotherapy, although effective against primary tumors, may promote metastasis by causing the release of proinflammatory factors from damaged cells. Here, polymeric nanoparticles that deliver chemotherapeutics and scavenge proinflammatory factors simultaneously to inhibit chemotherapy-induced breast cancer metastasis are developed. The cationic nanoparticles can adsorb cell-free nucleic acids (cfNAs) based on charge-charge interaction, which downregulates the expression of Toll-like receptors and then reduces the secretion of inflammatory cytokines. Through in vitro structural optimization, cationic polyamidoamine (PAMAM) dendrimers modified with drug-binding dodecyl groups and diethylethanolamine surface groups (PAMAM-G3-C125 -DEEA20 ) exhibit the most desirable combination of nanoparticle size (≈140nm), drug loading, cytotoxicity, cfNA binding, and anti-inflammatory activity. In the mouse models of breast cancer metastasis, paclitaxel-loaded nanoparticles reduce serum levels of cfNAs and inflammatory cytokines compared with paclitaxel treatment alone and inhibit both primary tumor growth and tumor metastasis. Additionally, no significant side effects are detected in the serum or major organs. These results provide a strategy to deliver chemotherapeutics to primary tumors while reducing the prometastatic effects of chemotherapy.

A new core-shell-type nanoparticle loaded with paclitaxel/norcantharidin and modified with APRPG enhances anti-tumor effects in hepatocellular carcinoma.

Nanoparticle delivery systems have been shown to improve the therapeutic efficacy of anti-cancer drugs, including a variety of drugs for the treatment of hepatocellular carcinoma (HCC). However, the current systems show some limitations, and the delivery of more effective nanoparticle systems for anti-HCC drugs with better targeting ability are needed. Here, we created paclitaxel (PTX)/norcantharidin (NCTD)-loaded core–shell lipid nanoparticles modified with a tumor neovasculature-targeted peptide (Ala-Pro-Arg-Pro-Gly, APRPG) and investigated their anti-tumor effects in HCC. Core–shell-type lipid nanoparticles (PTX/NCTD-APRPG-NPs) were established by combining poly(lactic-co-glycolic acid) (PLGA)-wrapped PTX with phospholipid-wrapped NCTD, followed by modification with APRPG. For comparison, PTX-loaded PLGA nanoparticles (PTX-NPs) and PTX/NCTD-loaded core–shell-type nanoparticles without APRPG (PTX/NCTD-NPs) were prepared. The in vitro and in vivo anti-tumor effects were examined in HepG2 cells and tumor-bearing mice, respectively. Morphological and release characterization showed that PTX/NCTD-APRPG-NPs were prepared successfully and achieved up to 90% release of PTX in a sustained manner. Compared with PTX/NCTD-NPs, PTX/NCTD-APRPG-NPs significantly enhanced the uptake of PTX. Notably, the inhibition of proliferation and migration of hepatoma cells was significantly higher in the PTX/NCTD-APRPG-NP group than those in the PTX-NP and PTX/NCTD-NP groups, which reflected significantly greater anti-tumor properties as well. Furthermore, key molecules in cell proliferation and apoptosis signaling pathways were altered most in the PTX/NCTD-APRPG-NP group, compared with the PTX-NP and PTX/NCTD-NP groups. Collectively, PTX/NCTD-loaded core–shell lipid nanoparticles modified with APRPG enhance the effectiveness of anti-HCC drugs and may be an effective system for the delivery of anti-HCC drugs.

Improved paclitaxel delivery with PEG-b-PLA/zein nanoparticles prepared via flash nanoprecipitation

Polymeric micelle is a promising vehicle to improve the bioavailability and clinical outcomes of paclitaxel (PTX) which has been proven effective in the treatment of a wide range of cancers. However, conventional PTX formulation with the amphiphilic PEG-b-PLA usually suffers from insufficient PTX loading, low stability of PTX-micelles, and rapid PTX release due to low compatibility between PTX and PLA, limiting its clinical application. In this study, a novel nanoparticle platform was developed to improve the stability of PTX-loaded nanoparticles (NPs) and the delivery efficacy of PTX by integrating the flash nanoprecipitation (FNP) technique and a combination of amphiphilic PEG-PLA and super hydrophobic zein. The incorporation of zein led to the formation of distinct hydrophobic interiors of NPs which enhanced the interaction between PTX and NPs, therefore improving the encapsulation efficiency of PTX and sustained drug release compared with PEG-PLA micelles without zein. In addition, FNP allowed facile fabrication of PTX-NPs with smaller sizes and higher stability. These PTX-NPs showed superior sustained release of PTX and good cancer cell-killing in vitro. Among them, PTX-5k-16k-1Z NPs exhibited excellent biosafety and anti-tumor efficacy in a xenograft tumor model in mice, suggesting great potential in the delivery of hydrophobic drugs for cancer therapy.

Optimum inhibition of MCF-7 breast cancer cells by efficient targeting of the macropinocytosis using optimized paclitaxel-loaded nanoparticles

AimsBreast cancer (BC) is the third leading cause of death among other cancer types. Worldwide, it is the most common harmful disease in women, representing 1/4 of all cancers. Treatment of BC remains an ongoing challenge to most researchers. Understanding how cancer cells differ from normal cells can enhance drug targeting and overall disease progression. Endocytosis is a major physiological process modified in cancer cells and affects the cellular uptake of chemotherapeutic agents. MCF-7 breast cancer cells exhibit constitutive macropinocytic activity in comparison to normal non-macropinocytic MCF-10A breast cells. Therefore, we hypothesized that blocking the macropinocytosis mechanism in MCF-7 cells may inhibit the cancer progression while maintaining the safety of normal cells. Main methodsUsing nano-precipitation technique, paclitaxel-PLGA-NPs were successfully prepared in the size range and charge required to opt for macropinocytosis in MCF-7 cells. Key findingsUptake and endocytosis inhibitor assays indicated that the developed NPs acquired size and surface charges that efficiently target macropinocytosis of MCF-7 cells. Paclitaxel-loaded PLGA-NPs showed higher efficacy against MCF-7 cells, while providing no toxicity on normal MCF-10A cells. Metabolomics analysis indicated the nutrients deprivation because of occupying the macropinocytosis. However, treatment of fresh MCF-7 cancer cells by metabolites secreted from PLGA-NPs-treated MCF-7 cells showed a potential metastatic activity. Thus, co- administration with an anti-metastatic drug is advised. SignificanceCollectively, adjusting the size and surface characteristics of a drug can critically control its cellular uptake, affecting the efficacy of drugs and the microenvironment of cancer cells.

Effects of particle size and release property of paclitaxel-loaded nanoparticles on their peritoneal retention and therapeutic efficacy against mouse malignant ascites

Malignant ascites accounts for abdominal pain, dyspnea and anorexia, all of which decrease quality of life in cancer patients. Intraperitoneal chemotherapy is a useful method for managing malignant ascites and nanoparticulate drug delivery system makes it more effective by increasing peritoneal retention of anti-cancer drugs. In this study, we prepared paclitaxel-loaded emulsions and liposomes with different particle sizes and drug release properties, and evaluated their peritoneal retention and therapeutic efficacy in Ehrlich’s ascites carcinoma (EAC)-bearing mice. Liposomes with the size of 100 nm were rapidly absorbed from peritoneal cavity into blood after intraperitoneal injection into EAC-bearing mice, whereas 1000-nm liposomes were highly retained in peritoneal cavity. Accordingly, 1000 nm liposomes significantly prolonged survival time of EAC-bearing mice but did not inhibit the ascites accumulation because of too poor paclitaxel release. On the other hand, although peritoneal retention of emulsions themselves was similar irrespective of their sizes, 270-nm emulsions showed the higher PTX retention in ascites than other emulsions, and resulted in significantly prolonged survival time and lower accumulation of ascites in EAC-bearing mice. These results indicate that not only particle size but drug release property is one of key determinants of the biodisposition and therapeutic efficacy of intraperitoneally injected nanoparticulate PTX against malignant ascites.

Development of the Composition and Technology for Obtaining Paclitaxel Nanoscale Formulation Consisting of a Conjugate of Polymer Particles with a Protein Vector Molecule

Introduction. The use of the anticancer drug paclitaxel is limited due to its high toxicity and lipophilicity. A new polymer composition of paclitaxel has been proposed, which provides targeted transport of the drug into tumor cells and improves its safety.Aim. Method development for preparation of a novel paclitaxel formulation consisting of a conjugate of PLGA nanoparticles with the third domain of alpha-fetoprotein.Materials and methods. The object of this study is paclitaxel-loaded nanoparticles based on a copolymer of lactic and glycolic acids, the surface of which is modified with a vector molecule - the recombinant third domain of alpha-fetoprotein. Nanoparticles were obtained by single emulsification method and precipitation. Conjugation with a protein molecule was performed by the carbodiimide method. The analysis of the obtained nanoparticles was carried out using dynamic and electrophoretic light scattering, high performance liquid chromatography, dialysis membrane method.Results and discussion. Synthesis of paclitaxel-loaded nanoparticles based on a copolymer of lactic and glycolic acids and its conjugation optimization under varying a wide range of conditions have been carried out. The resulting conjugate had an average diameter of 280 ± 12 nm. The conjugation efficiency was 95 %. The release of paclitaxel from the polymer matrix in the release medium was 65 % in 220 h.Conclusions. A method of obtaining and substantiating the composition of the original nanosized form of paclitaxel is proposed. The possibility of prolonged release of paclitaxel from the polymer matrix has been shown.

Ultrasound-Induced Microbubble Cavitation Combined with Paclitaxel-Loaded Nanoparticles for the Elimination of PC-3 Cells in vitro

Castration-resistant prostate cancer (CRPC) and its metastases are the main reasons for the high mortality of prostate cancer. Currently, paclitaxel (PTX)-based chemotherapeutics are used as first-line drugs to treat CRPC, but this treatment does not show good effects and is accompanied by serious side effects, which may be because intravenously injected chemotherapeutic drugs have difficulties gathering at the tumor site. Therefore, a safe and effective drug delivery carrier is urgently needed to enhance the therapeutic effects of chemotherapeutic drugs against CRPC. Methoxy polyethylene glycol-polylacticco-glycolic acid-polylysine (mPEG-PLGA-PLL) nanoparticles (NPs) have shown high drug encapsulation efficiency and good therapeutic effects against ovarian cancer and pancreatic cancer, but there are few studies on their treatment against CRPC. To expand the applications of mPEG-PLGA-PLL NPs, in this study, mPEG-PLGA-PLL NPs loaded with PTX (PTX-NPs) were synthesized. The synthesized PTX-NPs had a uniform particle size and no obvious aggregation. PTX-NPs can be uptaked by PC-3 cells, which significantly promotes the inhibition of proliferation and apoptosis effects of PTX on cells and reduces the expression levels of CDK6, Cyclin D1 and Bcl-2 (cyclins and an apoptosis inhibitor), and these effects can be further enhanced by ultrasound-induced microbubble cavitation (UIMC). Our research provides a new nanocarrier for the treatment of CRPC, laying the foundation for further research in the future.

High Solubilization and Controlled Release of Paclitaxel Using Thermosponge Nanoparticles for Effective Cancer Therapy.

Cancer, which is a leading cause of death, contributes significantly to reducing life expectancy worldwide. Even though paclitaxel (PTX) is known as one of the main anticancer drugs, it has several limitations, including low solubility in aqueous solutions, a limited dosage range, an insufficient release amount, and patient resistance. To overcome these limitations, we suggest the development of PTX-loaded thermosponge nanoparticles (PTX@TNP), which result in improved anticancer effects, via a simple nanoprecipitation method, which allows the preparation of PTX@TNPs with hydrophobic interactions without any chemical conjugation. Further, to improve the drug content and yield of the prepared complex, the co-organic solvent ratio was optimized. Thus, it was observed that the drug release rate increased as the drug capacity of PTX@TNPs increased. Furthermore, increasing PTX loading led to considerable anticancer activity against multidrug resistance (MDR)-related colorectal cancer cells (HCT 15), implying a synergistic anticancer effect. These results suggest that the solubilization of high drug amounts and the controlled release of poorly water-soluble PTX using TNPs could significantly improve its anticancer therapy, particularly in the treatment of MDR-p-glycoprotein-overexpressing cancers.