Hydrophobic Anticancer Drug Research Articles

Self-assembled sustainable bionanocomposite hydrogels from chitosan for the combination chemotherapy of hydrophobic and hydrophilic drugs.

Self-assembled hydrogels derived from naturally sourced polymers have gained significant interest in drug delivery applications, owing to their potential, exceptional biocompatibility and sustainable properties. This work presents the development and application of self-assembled nanocomposite hydrogels from chitosan and nanosilver as a pH responsive drug delivery system for the controlled release of doxorubicin and paclitaxel in anticancer therapy. Chitosan was functionalized with 4-formyl benzoic acid for incorporating both hydrophobic and hydrophilic anticancer drugs. The self-assembled nanocomposite hydrogels formed from chitosan and 4-formyl benzoic acid by various non-covalent interactions were studied by FT-IR, Dynamic Light Scattering (DLS), and rheology analysis. Rheology studies demonstrated the hydrogel's shear-thinning nature, enabling easy injection. The antibacterial activity can be evidenced by agar-well diffusion assay and MIC values were measured. The antibacterial effect was analyzed by agar-well diffusion assays and H2-DCFDA assay, providing a comprehensive understanding. In-vivo pharmacokinetic studies on Wistar rats demonstrated promising and effective systemic circulation of drug loaded material in blood, thus supporting its potential for therapeutic applications. All these studies and results demonstrates feasibility and a novel synergistic dual drug delivery approach, promising the synergy between hydrophobic paclitaxel (PTX) and hydrophilic Doxorubicin hydrochloride (Dox.HCl), for improved anticancer efficacy.

Effect of biosurfactants on the self-assembly behavior and drug encapsulation for branched block copolymers

For the past few years, block copolymers have attracted extensive attention in the field of drug delivery. In this work, the hyperbranched PEO-PPO block copolymer H1304 having the same PEO segments and PPO segments as the commercially available 4-branched block copolymer Tetronic1304 was synthesized. Compared with T1304, H1304 was characterized by lower cloud point, smaller critical micelle concentration (CMC), larger micellar size and better drug solubilization capacity. The effect of three biosurfactants lecithin (PC), alkyl glycogen (APG), sodium deoxycholate (NaDC) on the aggregation behavior of H1304 and T1304 were researched. Meanwhile, the solubilization and in vitro release properties of hydrophobic anticancer drug podophyllotoxin were also evaluated. The addition of PC or APG to form a mixed micelle reduced the cloud point and CMC, optimized the drug carrier characteristics. NaDC exhibited different effects due to its unique disclike surface structure. NaDC formed back-to-back aggregates, which interfered the self-assembly process of block copolymer and in turn caused variation of the copolymer micellar properties. The study of mixed systems consisting of biosurfactants and block copolymers will help to change the performance of copolymers in various pharmaceutical fields and contribute to the application of copolymers as drug carriers in drug delivery systems.

Tumor targeting pH-triggered fluorescence-switchable hyaluronic acid-based micelles with aggregation-induced emission activity for tracing drug release and intelligent drug delivery

In this study, an amphiphilic polymer (Bio-HA(TPE-CN)-mPEG) was designed and synthesized, which was fabricated by introducing hydrophobic aggregation-induced emission (AIE) fluorophore, acid-labile imine bond, methoxy poly (ethylene glycol) (mPEG) and tumor targeting ligand biotin to the backbone of hyaluronic acid. The polymer could self-assemble into micelles and solubilize hydrophobic anticancer drugs. In vitro drug release study indicated that the micelles could disassemble rapidly under acidic environment. The involvement of biotin and HA could enhance the cellular uptake of micelles by tumor cells. Modification of micelles by mPEG could minimize non-specific protein adsorption. Fluorescence studies indicated that the micelles exhibited excellent AIE features and emitted intense long-wavelength fluorescence. More excitingly, the micelles were red emissive in the normal physiological environment, but switched to blue fluorescence in the acidic tumor environment, which could be further applied for real-time monitoring and quantification of the drug release. The in vivo antitumor efficacy study demonstrated the superior antitumor activity of the PTX-loaded micelles. The Bio-HA(TPE-CN)-mPEG micelles were promising drug carriers for chemotherapy and bioimaging.

Enzyme-Triggered Degradation of Supramolecularly Cross-Linked Polymersomes of Azobenzene-Based Polyurethane: Cell-Selective Anticancer Drug Release.

Enzyme-responsive self-assembled nanostructures for drug delivery applications have gained a lot of attention, as enzymes exhibit dysregulation in many disease-associated microenvironments. Azoreductase enzyme levels are strongly elevated in many tumor tissues; hence, here, we exploited the altered enzyme activity of the azoreductase enzyme and designed a main-chain azobenzene-based amphiphilic polyurethane, which self-assembles into a vesicular nanostructure and is programmed to disassemble in response to a specific enzyme, azoreductase, with the help of the nicotinamide adenine dinucleotide phosphate (NADPH) coenzyme in the hypoxic environment of solid tumors. The vesicular nanostructure sequesters, stabilizes the hydrophobic anticancer drug, and releases the drug in a controlled fashion in response to enzyme-triggered degradation of azo-bonds and disruption of vesicular assembly. The biological evaluation revealed tumor extracellular matrix pH-induced surface charge modulation, selective activated cellular uptake to azoreductase overexpressed lung cancer cells (A549), and the release of the anticancer drug followed by cell death. In contrast, the benign nature of the drug-loaded vesicular nanostructure toward normal cells (H9c2) suggested excellent cell specificity. We envision that the main-chain azobenzene-based polyurethane discussed in this manuscript could be considered as a possible selective chemotherapeutic cargo against the azoreductase overexpressed cancer cells while shielding the normal cells from off-target toxicity.

Core-Tunable Dendritic Polymer: A Folate-Guided Theranostic Nanoplatform for Drug Delivery Applications.

Clinical application of anticancer drugs is mostly limited due to their hydrophobic nature, which often results in lower bioavailability and lesser retention in systemic circulation. Despite extensive research on the development of targeted drug delivery systems for cancer treatment, delivery of hydrophobic therapeutic drugs to tumor cells remains a major challenge in the field. To address these concerns, we have precisely engineered a new hyperbranched polymer for the targeted delivery of hydrophobic drugs by using a malonic acid-based A2B monomer and 1,6-hexanediol. The choice of monomer systems in our design allows for the formation of higher molecular weight polymers with hydrophobic cavities for the efficient encapsulation of therapeutic drugs that exhibit poor water solubility. Using several experimental techniques such as NMR, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), Fourier transform-infrared (FT-IR), and gel permeation chromatography (GPC), the synthesized polymer was characterized, which indicated its dendritic structure, thermal stability, and amorphous nature, making it suitable as a drug delivery system. Following characterizations, theranostic nanoplatforms were formulated using a one-pot solvent diffusion method to coencapsulate hydrophobic drugs, BQU57 and doxorubicin. To achieve targeted delivery of loaded therapeutic drugs in A549 cancer cells, the surface of the polymeric nanoparticle was conjugated with folic acid. The therapeutic efficacy of the delivery system was determined by various cell-based in vitro experiments, including cytotoxicity, cell internalizations, reactive oxygen species (ROS), apoptosis, migration, and comet assays. Overall, findings from this study indicate that the synthesized dendritic polymer is a promising carrier for hydrophobic anticancer drugs with higher biocompatibility, stability, and therapeutic efficacy for applications in cancer therapy.

Two-dimensional polydopamine nanosheet-based thermosensitive supramolecular hydrogels for photothermal-chemo synergistic treatment of melanoma

The development of injectable thermosensitive hydrogels with photothermal elimination of tumors and precisely controllable drug release properties is critical for tumor eradication. Herein, a novel injectable thermosensitive supramolecular hydrogel PDAns@CPT-peg/α-CD was developed, which was formed by using two-dimensional polydopamine nanosheets (PDAns) as the photothermal backbone, loaded with the PEGylated camptothecin prodrug (CPT-peg) through π-π stacking and hydrophobic binding, and then crosslinked by the introduction of α-cyclodextrin (α-CD) host–guest self-assembly. PDAns as hydrogel skeleton endowed the hydrogel with excellent photothermal conversion effect, and the large specific surface area of PDAns enables efficient loading of hydrophobic anticancer drugs and avoids undesired leakage. Moreover, the dynamic host–guest cross-linking endows the hydrogel with reversible gel-sol transition and injectability, the gel-sol transition temperature can be easily tunable by the CD concentration, under 808 nm laser irradiation, the PDAns@CPT-peg/α-CD hydrogel can be rapidly heated to the temperature required for photothermal therapy, simultaneously triggering the thermosensitive gel-sol transition followed by the on-demand release of CPT-peg. In vivo evaluation demonstrated that the synergistic photothermal-chemotherapeutic effect mediated by PDAns@CPT-peg/α-CD hydrogel almost eradicated melanoma under low-dose NIR laser (0.15 W cm−2) irradiation. This work provides an effective and convenient strategy for constructing a multifunctional hydrogel platform for the photothermal-chemo synergistic treatment of tumors.

Synergistic effects of graphene quantum dots nanocarriers and folic acid targeting agent on enhanced killing of breast cancer cells by tamoxifen

AbstractIn this study, a new targeted and controlled‐release drug delivery system based on graphene quantum dots (GQDs) was fabricated. The fluorescent GQDs were synthesized via an environmentally‐friendly chemical oxidation method, using graphene oxide (GO) as a precursor and hydrogen peroxide and ammonia solution as oxidants. Folic acid (FA), as a targeting agent, was bound to GQDs through strong amide covalent bindings, and tamoxifen (TMX), as a hydrophobic anticancer drug, was non‐covalently attached to the nanocarrier via π–π stacking bonds. The as‐prepared GQDs and TMX/FA‐GQDs were characterized using field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FTIR), UV/Vis spectroscopy (UV/Vis), and photoluminescence spectroscopy (PL). The resulting TMX/GQDs demonstrated pH‐sensitive release behaviour with an overall release of 85% and 58% at pH 5.5 and 7.4, respectively, after 120 h. Also, the MTT assay test performed on MCF‐7 cells presented negligible toxicity of the nanocarriers, even at high concentrations. At the same time, the targeted nanocarrier, TMX/FA‐GQDs, showed much more toxicity towards MCF‐7 cells than the non‐targeted one and free TMX.

Empowering hydrophobic anticancer drugs by ultrashort peptides: General Co-assembly strategy for improved solubility, targeted efficacy, and clinical application

The current state of drug delivery systems allows for the resolution of specific issues like inadequate solubility, limited targeting capabilities, and complex preparation processes, requiring tailored designs for different drugs. Yet, the major challenge in clinical application lies in surmounting these obstacles with a universal carrier that is effective for a variety of anticancer drugs. Herein, with the help of computer simulation, we rationally design ultrashort peptides GY and CCYRGD, which can co-assemble with hydrophobic anticancer drugs into nanoparticles with enhanced solubility, targeting ability and anticancer efficacy. Taking 7-ethyl-10-hydroxy camptothecin (SN38) as a model anticancer drug, the co-assembled SN38-GY-CCYRGD nanoparticles significantly enhance the water solubility of SN38 by more than three orders of magnitude. The as-prepared nanoparticles can effectively kill cancer cells, e.g., human small cell lung cancer (A549) cells with a notable cell mortality rate of 71%. Mice experimental results demonstrate the nanoparticles’ efficient targeting capability, marked reducing the toxicity to normal tissues while improving antitumor efficacy. This work presents a novel drug delivery method, integrating effective, targeted, and safe strategies into a comprehensive carrier system, designed for the administration of hydrophobic anticancer drugs.

Redox-Responsive Gold Nanoparticles Coated with Hyaluronic Acid and Folic Acid for Application in Targeting Anticancer Therapy.

Methotrexate (MTX) has poor water solubility and low bioavailability, and cancer cells can become resistant to it, which limits its safe delivery to tumor sites and reduces its clinical efficacy. Herein, we developed novel redox-responsive hybrid nanoparticles (NPs) from hyaluronic acid (HA) and 3-mercaptopropionic acid (MPA)-coated gold NPs (gold@MPA NPs), which were further conjugated with folic acid (FA). The design of FA-HA-ss-gold NPs aimed at enhancing cellular uptake specifically in cancer cells using an active FA/HA dual targeting strategy for enhanced tumor eradication. MTX was successfully encapsulated into FA-HA-ss-gold NPs, with drug encapsulation efficiency (EE) as high as >98.7%. The physicochemical properties of the NPs were investigated in terms of size, surface charges, wavelength reflectance, and chemical bonds. MTX was released in a sustained manner in glutathione (GSH). The cellular uptake experiments showed effective uptake of FA-HA-ss-gold over HA-ss-gold NPs in the deep tumor. Moreover, the release studies provided strong evidence that FA-HA-ss-gold NPs serve as GSH-responsive carriers. In vitro, anti-tumor activity tests showed that FA-HA-ss-gold/MTX NPs exhibited significantly higher cytotoxic activity against both human cervical cancer (HeLa) cells and breast cancer (BT-20) cells compared to gold only and HA-ss-gold/MTX NPs while being safe for human embryonic kidney (HEK-293) cells. Therefore, this present study suggests that FA-HA-ss-gold NPs are promising active targeting hybrid nanocarriers that are stable, controllable, biocompatible, biodegradable, and with enhanced cancer cell targetability for the safe delivery of hydrophobic anticancer drugs.

Lauric acid-based thermosensitive delivery system for the treatment of head and neck squamous cell carcinoma

Traditional treatments for head and neck squamous cell carcinoma (HNSCC) such as surgery, radiation therapy, and chemotherapy, often have severe side effects. Local delivery of chemotherapeutic agents can be a promising approach to minimise systemic toxicity and improve efficacy. Lauric acid (LA), was explored as a novel injectable thermosensitive drug reservoir as a depot for sustained release of anticancer drugs to treat HNSCC. LA was characterised in terms of melting temperature and gelation time. The efficacy of LA-based drug formulations was tested in vitro in a HNSCC cell line and in vivo in a mouse model of HNSCC. LA was modified to have a melting point of 38.5 °C and a gelation time of 40 s at 37.5 °C, rendering it suitable for injection at body temperature. LA- based doxorubicin (DOXO) formulation showed slow release with a maximum of 18% release after 3 days. The in vitro study showed that LA enhanced the cytotoxic effect of DOXO. LA combined with DOXO prevented tumour progression and LA alone significantly reduced the original tumour volume compared to the untreated control group. These findings confirmed that LA can function as practical carrier for the local delivery of chemotherapeutics and provides a safe and simple strategy for the delivery of hydrophobic anticancer drugs and warrant further testing in clinical trials.

Synthesis and characterization of the redox-responsive amphiphilic fluorescent alginate derivatives as the multi-functional hydrophobic anticancer drug delivery system with visualization and sustained release

To develop the multi-functional hydrophobic anticancer drug carriers with visualization and sustained release, a novel amphiphilic alginate derivative (LSA-SS-DEAC) containing chromophobe groups was designed and synthesized by grafting hydrophobic fluorescent molecule, 7-(diethylamino-coumarin-3-carboxylic acid (DEAC-COOH) onto hydrophilic low molecular alginate backbone through cystamine by water-soluble carbodiimide chemical method. The molecular structure and self-assembly properties of the synthesized LSA-SS-DEAC were characterized. Furthermore, the encapsulation of anti-cancer drugs, doxorubicin hydrochloride (DOX) in LSA-SS-DEAC self-assembled micelles was realized by ultrasonic dialysis method. Subsequently, the in vitro drug release behavior and in vitro cytotoxicity of LSA-SS-DEAC micelles in simulated tumor microenvironment were also studied. The resultant LSA-SS-DEAC with the critical micelle concentration (CMC) of 0.26 mg/mL exhibited the ability to spontaneously form spherical micelles with the particle size of 250.2 ± 4.3 nm (PDI = 0.23) and zeta potential of −49.1 ± 0.4 mV, which presented good stability in pH 7.4 PBS and excellent fluorescence properties and redox responsiveness. The drug-loaded LSA-SS-DEAC micelles had the optimal EE value of about 42.2% when the DOX/LSA-SS-DEAC mass ratio was 3:10. Meanwhile, The drug-loaded LSA-SS-DEAC micelles exhibited sustained release in GSH-free environment, and the cumulative drug release rates were 40.3% and 46.6% in pH 7.4 and 5.0 PBS for 48 h, respectively. However, in the simulated tumor cell microenvironment (pH 5.0 PBS + 10 mM GSH), the disulfide bond between the core-shell was broken under the GSH trigger, and the LSA-SS-DEAC micelles collapsed, resulting in a cumulative drug release rate of about 64% at 12 h. In vitro cytotoxicity results showed that LSA-SS-DEAC had low cytotoxicity, and revealed obvious inhibitory effect on HeLa cells after DOX loading. Fluorescence imaging results indicated that LSA-SS-DEAC micelles could emit green light after ingested by cells, and their fluorescence properties were not affected after encapsulation of DOX. Accordingly, LSA-SS-DEAC micelles had the potential for drug localization tracking and rapid drug release at focal sites, which could be expected to be an ideal drug carriers for hydrophobic anticancer drug delivery.

Cyclophosphamide Loading and Controlled Release in MIL-100(Fe) as an Anti-breast Cancer Carrier: In vivo In vitro Study.

Biocompatible MIL-100 (Fe), a metal organic framework material, has recently attracted increasing attention in biomedical engineering. The high surface area, pore volume, and accessible Lewis acid sites make MIL-100 (Fe) a proper candidate for hydrophobic anticancer drug loading and storage. In this study, a novel investigation of cyclophosphamide (CP) -loaded MIL-100(Fe) (MIL- 100(Fe)/CP) and a simulation of drug loading at a molecular level is presented. This research used a facile synthesis method to prepare MIL-100(Fe), which addresses the high temperature and pressure challenges of synthesis methods. MIL-100(Fe) and MIL-100(Fe)/CP were characterized using x-ray diffraction (XRD), Brunauer-Emmett-Teller (BET), Fourier transform infrared (FTIR), and field emission scanning electron microscopy (FESEM). The carriers' drug loading and release behavior are determined by using UV-visible spectrophotometry. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay is applied to examine the biocompatibility and the anticancer effect of MIL-100(Fe)/CP on the human breast cancer cell line (MCF-7). In vivo</i> antitumor experiments and histological observation reveal inhibition properties of MIL-100(Fe)/CP on the tumor cells. MIL-100(Fe)/CP, with 37.41% drug payload, represents impressive antitumor activity.

Tunable self-assembly of lipid-based block polymeric micelles with temperature-sensitive poly(vinylcaprolactam) shell for effective anticancer drug delivery

Lipids, as naturally occurring biomolecules have emerged as promising carriers for delivering various therapeutic agents. However, only a few attempts have been made in terms of their applications as amphiphilic block copolymers for anticancer drug delivery. In this work, a biocompatible micellar drug delivery system with fatty acid-based polymer core and temperature-sensitive shell was developed. A series of amphiphilic block copolymers poly(vinyl stearate)/poly(vinyl laurate)-b-poly(N-vinylcaprolactam) (PVS/PVL-b-PNVCL) were synthesized via microwave-assisted reversible addition-fragmentation chain transfer polymerization in a controlled fashion. By varying the fatty acid type and hydrophilic/hydrophobic block lengths, the self-assembly behaviour of the block copolymer micelles proved to be highly tunable in terms of their morphology and particle size. Nile Red and hydrophobic anticancer drug doxorubicin (DOX) were effectively incorporated into the micelles, demonstrating high drug loading capacity, good serum stability, and temperature-dependent drug release characteristics of the polymeric micelles. In vitro studies using cell models revealed that blank PVS -b-PNVCL micelles are biocompatible with different cell lines, while DOX-loaded micelles were internalized into and accumulated in the cells, showing a high cytotoxic effect against HeLa cells. These findings suggest an opportunity for the development of safe and efficient lipid-based micellar system for smart drug delivery and cancer treatments.

Inherently targeted estradiol-derived carbon dots for selective killing of ER (+) breast cancer cells via oridonin-triggered p53 pathway activation.

One of the most prevalent cancers globally is breast cancer and approximately two thirds of the breast cancers are hormone receptor positive with estrogen receptors (ER) being a prominent target. Notably, p53 that controls several cellular functions and prevents tumor formation, gets suppressed in breast cancers. Reactivation of p53 can lead to cell cycle arrest as well as apoptosis. Therefore, targeting the estrogen receptor for selective delivery of anticancer drugs that can reactivate p53 in ER (+) breast cancers can be a crucial method in breast cancer therapy. Herein, we have designed and developed estradiol-derived inherently targeted specific carbon dots (E2-CA-CD) from 17β-estradiol and citric acid following a solvothermal method. The synthesized carbon dots were characterized using spectroscopic and microscopic techniques. The water soluble, intrinsically fluorescent E2-CA-CD showed excellent biocompatibility in MCF-7, MDA-MB-231 as well as NIH3T3 cells and demonstrated target specific bioimaging in ER (+) MCF-7 cells due to the overexpressed ER receptors. Furthermore, oridonin, a well-known hydrophobic anticancer drug capable of upregulating the p53 pathway, was loaded on the carbon dots to increase its bioavailability. E2-CA-CD-Ori caused ∼2.2 times higher killing in ER (+) MCF-7 cells compared to ER (-) MDA-MB-231 cells and normal cells NIH3T3. Also, E2-CA-CD-Ori showed ∼3 fold better killing in MCF-7 cells compared to native oridonin. E2-CA-CD-Ori-induced killing of MCF-7 cells took place through the early to late apoptotic pathway along with the elevation of the intracellular ROS level. Importantly, E2-CA-CD-Ori triggered the activation of the p53 pathway in MCF-7 cells, which in turn induced apoptosis involving the upregulation of Bax and downregulation of Bcl-2 leading to the selective and efficient killing of ER (+) MCF-7 cells.

Self-assembly of interpolyelectrolyte complexes and mixed micelles from guanidinium and phosphonate derivatives of p–tert–butylthiacalix[4]arene and solubilization of paclitaxel

In this work, supramolecular assemblies based on p–tert–butylthiacalix[4]arene derivatives functionalized with charged guanidinium and phosphonate fragments in the 1,3–alternate conformation were obtained in the presence of the surfactants. Two main approaches based on the macrocyclic compounds have been presented for supramolecular assembling, i.e. (i) the use of two oppositely charged macrocyclic compounds forming interpolyelectrolyte complexes; and (ii) the use of ionogenic macrocycles and low molecular surfactants forming mixed micelles. Self-assembling properties of guanidinium and phosphonate derivatives of p–tert–butylthiacalix[4]arene and paclitaxel solubilization of interpolyelectrolyte complexes and mixed micelles were examined and compared for various compositions. The obtained supramolecular associates were further investigated to load hydrophobic anticancer drug paclitaxel that is insoluble in water and requires solubilization prior to application. It was established that mixed micelles containing thiacalix[4]arene with guanidinium fragments were more effective in solubilizing paclitaxel against interpolyelectrolyte approach. The micelles obtained in the presence of water-insoluble drug formed stable monodisperse colloidal system consisted of spherical particles (d = 192 ± 7 nm, ζ = 33 ± 4 mV for equimolar ratio of the components). The results offer a new strategy for the design of the interpolyelectrolyte complexes based on the macrocyclic building blocks for the solubilization of water-insoluble drugs.

Clickable polyethyleneimine incorporated into triblock copolymeric micelles as an efficient platform in the delivery of siRNA to NSCLC cells

The efficacy of transfection vectors to cross the endosomal membrane into the cytosol is a central aspect in the development of nucleic acid-based therapeutics. The challenge remains the same: Delivery, Delivery, Delivery. Despite a rational and appropriate construct of triblock polymeric micelles, which could serve as an ideal platform for the co-delivery of siRNAs and hydrophobic anticancer drugs, we show here its inability to properly convey oligonucleotides to their final destination. In order to overcome biological barriers, a linear PEI comprising two orthogonal groups was synthesized, holding an appropriate balance between safety and efficacy. Micellar carriers were then formulated with this polymer to enhance endosomal siRNA release. This chemical technology also addresses the two major challenges to consider when developing novel micellar products for siRNA delivery, namely cytotoxicity of polycations and endosomal escape. Herein, we demonstrate successful release of siRNA using a polymer tailoring strategy combined with a relevant in vitro approach, considering STAT3 as a promising target in the treatment of non-small cell lung cancer (NSCLC).

Polyamidoamine dendrimer-mediated hydrogel for solubility enhancement and anti-cancer drug delivery.

The application of hydrogels for anti-cancer drug delivery has garnered considerable interest in the medical field. Current cancer treatment approaches, such as chemotherapy and radiation therapy, often induce severe side effects, causing significant distress and substantial health complications to patients. Hydrogels present an appealing solution as they can be precisely injected into specific sites within the body, facilitating the sustainable release of encapsulated drugs. This localized treatment approach holds great potential for reducing toxicity levels and improving drug delivery efficacy. In this study we developed a hydrogel delivery system containing polyamidoamine (PAMAM) dendrimer and polyethylene glycol (PEG) for solubility enhancement and sustained delivery of hydrophobic anti-cancer drugs. The three selected model drugs, e.g. silibinin, camptothecin, and methotrexate, possess limited aqueous solubility and thus face restricted application. In the presence of vinyl sulfone functionalized PAMAM dendrimer at 45 mg/mL concentration, drug solubility is increased by 37-fold, 4-fold, and 10-fold for silibinin, camptothecin, and methotrexate, respectively. By further crosslinking of the functionalized PAMAM dendrimer and thiolated PEG, we successfully developed a fast-crosslinking hydrogel capable of encapsulating a significant payload of solubilized cancer drugs for sustained release. In water, the drug encapsulated hydrogels release 30%-80% of their loads in 1-4days. MTT assays of J82 and MCF7 cells with various doses of drug encapsulated hydrogels reveal that cytotoxicity is observed for all three drugs on both J82 and MCF7 cell lines after 48h. Notably, camptothecin exhibits higher cytotoxicity to both cell lines than silibinin and methotrexate, achieving up to 95% cell death at experimental conditions, despite its lower solubility. Our experiments provide evidence that the PAMAM dendrimer-mediated hydrogel system significantly improves the solubility of hydrophobic drugs and facilitates their sustained release. These findings position the system as a promising platform for controlled delivery of hydrophobic drugs for intratumoral cancer treatment.

Synthesis of heparin-and-poloxamer P407-based nanogel carrying PTX for orientating in treatment of breast cancer

In this study, nanogels based on the conjugation of heparin and poloxamer P407 (HR-P407) with different grafting ratios were successfully synthesised. The structural properties of products were evaluated by Fourier-transform infrared spectroscopy (FT-IR) and proton nuclear magnetic resonance (1H-NMR). The morphology and size of nanoparticles were assessed by dynamic light scattering (DLS) method, which showed that particle size distribution was from 144 nm to 214 nm. The HR-P407 nanogel systems were biocompatible and non-toxic to healthy cells. While free PTX displayed rapid and potent cytotoxic effects, PTX released from HR-P407 (1:10)/PTX demonstrated a gradual and sustained cytotoxicity. This controlled release mechanism allowed prolonged drug exposure, reducing acute toxicity and enhancing cytotoxicity over time. The results suggest that the synthesised nanogels can be used as an effective hydrophobic anticancer drug carrier system.

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.

Modification of Poly(Glycerol Adipate) with Tocopherol and Cholesterol Modulating Nanoparticle Self-Assemblies and Cellular Responses of Triple-Negative Breast Cancer Cells to SN-38 Delivery.

This study aimed to fabricate new variations of glycerol-based polyesters by grafting poly(glycerol adipate) (PGA) with hydrophobic bioactive moieties, tocopherol (TOC), and cholesterol (CHO). Their effects on nanoparticle (NP) formation, drug release, and cellular responses in cancer and normal cells were evaluated. CHO and TOC were successfully grafted onto PGA backbones with 30% and 50% mole grafting. Increasing the percentage of mole grafting in both molecules increased the glass transition temperature and water contact angle of the final polymers but decreased the critical micelle concentration of the formulated particles. PGA-TOC NPs reduced the proliferation of MDA-MB-231 cancer cells. However, they enhanced the proliferation of primary dermal fibroblasts within a specific concentration range. PGA-CHO NPs minimally affected the growth of cancer and normal cells. Both types of NPs did not affect apoptosis or the cell cycle of cancer cells. PGA-CHO and PGA-TOC NPs were able to entrap SN-38, a hydrophobic anticancer drug, with a particle size <200 nm. PGA-CHO NPs had a higher drug loading capacity and a greater drug release than PGA-TOC NPs. However, SN-38-loaded PGA-TOC NPs showed higher toxicity than SN-38 and SN-38-loaded PGA-CHO NPs due to the combined effects of antiproliferation and higher cellular uptake. Compared with SN-38, the drug-loaded NPs more profoundly induced sub-G1 in the cell cycle analysis and apoptosis of cancer cells in a similar pattern. Therefore, PGA-CHO and PGA-TOC polymers have potential applications as delivery systems for anticancer drugs.