Roles of ligand and TPGS of micelles in regulating internalization, penetration and accumulation against sensitive or resistant tumor and therapy for multidrug resistant tumors

Coadministration of Quercetin and Indocyanine Green via PEGylated Phospholipid Micelles for Augmented Chem-Photothermal Combination Tumor Therapy

A significant impediment persists in developing multicomponent nanomedicines designed to dismantle the heat shock protein (HSP)-based protective mechanism of malignant tumors during photothermal therapy. Herein, well-defined PEGylated phospholipid micelles were utilized to coencapsulate quercetin (QUE, a natural anticancer agent and potent HSP inhibitor) and indocyanine green (ICG, a photothermal agent) with the aim of achieving synchronized and synergistic drug effects. The subsequent investigations validated that the tailored micellar system effectively enhanced QUE's water solubility and augmented its cellular internalization efficiency. Intriguingly, the compositional PEGylated phospholipids induced extraordinary endoplasmic reticulum stress, thereby sensitizing the tumor cells to QUE. Furthermore, QUE played a crucial role in inhibiting the stress-induced overexpression of HSP70, thereby augmenting the photothermal efficacy of ICG. In systemic applications, the proposed nanotherapeutics exhibited preferential accumulation within tumors and exerted notable tumoricidal effects against 4T1 xenograft tumors under 808 nm near-infrared irradiation, facilitated by prominent near-infrared fluorescence imaging-guided chemo-photothermal therapy. Therefore, our strategy for fabricating multicomponent nanomedicines emerges as a coordinated platform for optimizing antitumor therapeutic efficacy and offers valuable insights for diverse therapeutic modalities.

Enhancing oral delivery and anticancer efficacy of 7-ethyl-10-hydroxycamptothecin through self-assembled micelles of deoxycholic acid grafted N'-nonyl-trimethyl chitosan

Irinotecan (CPT-11) is used as a first or second-line chemotherapy drug for the treatment and management of colorectal cancers. In vitro studies have shown that 7-ethyl-10-hydroxycamptothecin (SN38), the active metabolite of CPT-11, displays promising anticancer efficacy. However, its poor aqueous solubility and hydrolytic degradation result in its lower oral bioavailability and impracticable clinical application. To overcome these limitations, a novel amphiphilic chitosan derivative, deoxycholic acid decorated N'-nonyl-trimethyl chitosan, was synthesized. Nano-micelles loaded with SN38 were subsequently prepared to enhance the bioavailability and anti-tumor efficacy of the drug through oral administration. The nano-micelles demonstrated improved dilution stability, enhanced greater mucosal adherence, significant P-gp efflux inhibition, and increased drug transport in the intestine by paracellular and transcellular pathways. Consequently, both the in vivo pharmacokinetic profile and therapeutic efficacy of SN38 against cancer were substantially improved via the micellar system. Thus, the developed polymeric micelles can potentially enhance the SN38 oral absorption for cancer therapy, offering prospective avenues for further exploration.

Engineering extracellular vesicles mimetics for targeted chemotherapy of drug-resistant ovary cancer

Aim: To develop nanocarriers for targeting the delivery of chemotherapeutics to overcome multidrug-resistant ovarian cancer. Materials & methods: Doxorubicin-loaded nanovesicles were obtained through serial extrusion, followed by loading of P-glycoprotein siRNA and folic acid. The targeting ability and anticancer efficacy of the nanovesicles were evaluated. Results: The doxorubicin-loaded nanovesicles showed a high production yield. The presence of P-glycoprotein siRNA and folic acid resulted in reversed drug resistance and tumor targeting. This nanoplatform tremendously inhibited the viability of multidrug-resistant ovarian cancer cells, which was able to target tumor tissue and suppress tumor growth without adverse effects. Conclusion: These bioengineered nanovesicles could serve as novel extracellular vesicles mimetics for chemotherapeutics delivery to overcome multidrug resistance.

Ultra-small micelles together with UTMD enhanced the therapeutic effect of docetaxel on Glioblastoma

Owing to the difficult-to-penetrate blood-brain barrier (BBB), glioblastoma (GBM) doesn't respond well to the current chemical therapeutics. In this study, ultra-small micelles (NMs) self-assembled by RRR-a-tocopheryl succinate-grafted-ε-polylysine conjugate (VES-g-ε-PLL) as the delivery vehicle of chemical therapeutics in conjunction with ultrasound-targeted microbubble destruction (UTMD) to surmount BBB and treat GBM. Docetaxel (DTX) as a hydrophobic model drug was incorporated into NMs. DTX-loaded micelles (DTX-NMs) with 3.08% of drug loading exhibited a hydrodynamic diameter (33.2 nm) and positive Zeta potential (16.9 mV), having a remarkable tumor-permeating capacity. Furthermore, DTX-NMs presented good stability in physiologic condition. The sustained-release release profile of DTX-NMs was also displayed by dynamic dialysis. Treatment of DTX-NMs together with UTMD led to more pronounced apoptosis of C6 tumor cells than DTX-NMs alone. Moreover, compared with the DTX solution or DTX-NMs alone, the combination of DTX-NMs with UTMD had a stronger inhibitory effect on tumor growth for GBM-bearing rats. The median survival period of GBM-bearing rats was extended to 75 days in the DTX-NMs+UTMD group from under 25 days in the control group. The invasive growth of glioblastoma was largely inhibited by the combination of DTX-NMs with UTMD, which was demonstrated by staining of Ki67, caspase-3, and CD31, together with TUNEL assay. In conclusion, the combination of ultra-small micelles (NMs) with UTMD may be a promising strategy to overcome the limitations of the first-line chemotherapeutics against GBM.

TPGS Decorated Liposomes as Multifunctional Nano-Delivery Systems

Liposomes are sphere-shaped vesicles that can capture therapeutics either in the outer phospholipid bilayer or inner aqueous core. Liposomes, especially when surface-modified with functional materials, have been used to achieve many benefits in drug delivery, including improving drug solubility, oral bioavailability, pharmacokinetics, and delivery to disease target sites such as cancers. Among the functional materials used to modify the surface of liposomes, the FDA-approved non-ionic surfactant D-alpha-tocopheryl polyethylene glycol succinate (TPGS) is increasingly being applied due to its biocompatibility, lack of toxicity, applicability to various administration routes and ability to enhance solubilization, stability, penetration and overall pharmacokinetics. TPGS decorated liposomes are emerging as a promising drug delivery system for various diseases and are expected to enter the market in the coming years. In this review article, we focus on the multifunctional properties of TPGS-coated liposomes and their beneficial therapeutic applications, including for oral drug delivery, vaccine delivery, ocular administration, and the treatment of various cancers. We also suggest future directions to optimise the manufacture and performance of TPGS liposomes and, thus, the delivery and effect of encapsulated diagnostics and therapeutics.

Synergistic effect of doxorubicin lauroyl hydrazone derivative delivered by α-tocopherol succinate micelles for the treatment of glioblastoma

We hypothesized that tocopherol succinate (TOS) and D-α-tocopherol polyethylene2000 succinate (TPGS₂₀₀₀) micelles could work as a drug delivery system while enhancing the anti-cancer efficacy of doxorubicin lauryl hydrazone derivative (DOXC₁₂) for the treatment of glioblastoma. The DOXC₁₂-TOS-TPGS₂₀₀₀ micelles were formulated with synthesized DOXC₁₂ and TPGS₂₀₀₀. They showed a high drug loading of hydrophobic DOXC₁₂ (29%), a size of <100 nm and a pH sensitive drug release behaviour. In vitro, fast uptake of DOXC₁₂-TOS-TPGS₂₀₀₀ micelles by GL261 cells was observed. For cytotoxicity, DOXC₁₂-TOS-TPGS₂₀₀₀ micelles were evaluated on two glioblastoma cell lines and showed synergism between DOXC₁₂ and TOS-TPGS_2000. The higher cytotoxicity of DOXC₁₂-TOS-TPGS₂₀₀₀ micelles was mainly caused by necrosis. The DOXC₁₂-TOS-TPGS₂₀₀₀ micelles seem to be a promising delivery system for enhancing the anticancer efficacy of doxorubicin in glioblastoma (GBM).

pH and lipase-responsive nanocarrier-mediated dual drug delivery system to treat periodontitis in diabetic rats

Precise and controlled drug delivery to treat periodontitis in patients with diabetes remains a significant clinical challenge. Nanoparticle-based drug delivery systems offer a potential therapeutic strategy; however, the low loading efficiency, non-responsiveness, and single effect of conventional nanoparticles hinder their clinical application. In this study, we designed a novel self-assembled, dual responsive, and dual drug-loading nanocarrier system, which comprised two parts: the hydrophobic lipid core formed by 1, 2-Distearoyl-sn-glycero-3-phosphoethanolamine-Poly (ethylene glycol) (DSPE-PEG) loaded with alpha-lipoic acid (ALA); and a hydrophilic shell comprising a poly (amidoamine) dendrimer (PAMAM) that electrostatically adsorbed minocycline hydrochloride (Mino). This unique design allows the controlled release of antioxidant/ALA under lipase stimulation from periodontal pathogens and antimicrobial/Mino under the low pH of the inflammatory microenvironment. In vivo and in vitro studies confirmed that this dual nanocarrier could inhibit the formation of subgingival microbial colonies while promoting osteogenic differentiation of cells under diabetic pathological conditions, and ameliorated periodontal bone resorption. This effective and versatile drug-delivery strategy has good potential applications to inhibit diabetes-associated periodontal bone loss.

•

The nanocarriers are pH and lipase sensitive for controlled drug release.

•

The nanocarriers simultaneously exert antibacterial, antioxidant, anti-inflammatory, and osteogenic functions via the controlled release of antibacterial/Mino and antioxidant/ALA.

•

The nanocarriers offer a promising strategy to treat periodontitis under DM conditions.

Recent Developments in the Study of the Microenvironment of Cancer and Drug Delivery

Cancer is characterized by disrupted molecular variables caused by cells that deviate from regular signal transduction. The uncontrolled segment of such cancerous cells annihilates most of the tissues that contact them. Gene therapy, immunotherapy, and nanotechnology advancements have resulted in novel strategies for anticancer drug delivery. Furthermore, diverse dispersion of nanoparticles in normal stroma cells adversely affects the healthy cells and disrupts the crosstalk of tumour stroma. It can contribute to cancer cell progression inhibition and, conversely, to acquired resistance, enabling cancer cell metastasis and proliferation. The tumour's microenvironment is critical in controlling the dispersion and physiological activities of nano-chemotherapeutics which is one of the targeted drug therapy. As it is one of the methods of treating cancer that involves the use of medications or other substances to specifically target and kill off certain subsets of malignant cells. A targeted therapy may be administered alone or in addition to more conventional methods of care like surgery, chemotherapy, or radiation treatment. The tumour microenvironment, stromatogenesis, barriers and advancement in the drug delivery system across tumour tissue are summarised in this review.

Folate-modified triptolide liposomes target activated macrophages for safe rheumatoid arthritis therapy

Rheumatoid arthritis (RA) is an autoimmune disease characterized by synovial joint hyperplasia, joint inflammation, cartilage erosion and bone destruction. Macrophages play an essential role in the pathogenesis of RA, and folate receptor β (FR-β) is highly expressed on the surface of activated synovial macrophages in RA patients. Triptolide (TP) has anti-inflammatory properties, and it can protect the cartilage matrix, but its clinical application has been limited due to poor solubility, low bioavailability and systemic toxicity. Therefore, we constructed folate-modified triptolide liposomes (FA-TP-Lips) to target macrophages, thereby treating RA in a safe and effective way. The experiments indicated that FA-TP-Lips had properties of small particle size, uniform particle size distribution, high drug encapsulation and long circulation. Furthermore, FA-TP-Lips showed reduced cytotoxicity, increased cellular uptake and significant anti-inflammatory effects in vitro. It also inhibited osteoclastogenesis. In vivo experiments revealed that liposomes could prolong the circulation of TP in the body, as well as exhibit significant cartilage-protective and anti-inflammatory effects with lower toxicity compared with the free TP group, thereby providing a promising new approach for the treatment of RA.

Kinetics of Nanomedicine in Tumor Spheroid as an In Vitro Model System for Efficient Tumor-Targeted Drug Delivery With Insights From Mathematical Models

Numerous strategies have been developed to treat cancer conventionally. Most importantly, chemotherapy shows its huge promise as a better treatment modality over others. Nonetheless, the very complex behavior of the tumor microenvironment frequently impedes successful drug delivery to the tumor sites that further demands very urgent and effective distribution mechanisms of anticancer drugs specifically to the tumor sites. Hence, targeted drug delivery to tumor sites has become a major challenge to the scientific community for cancer therapy by assuring drug effects to selective tumor tissue and overcoming undesired toxic side effects to the normal tissues. The application of nanotechnology to the drug delivery system pays heed to the design of nanomedicine for specific cell distribution. Aiming to limit the use of traditional strategies, the adequacy of drug-loaded nanocarriers (i.e., nanomedicine) proves worthwhile. After systemic blood circulation, a typical nanomedicine follows three levels of disposition to tumor cells in order to exhibit efficient pharmacological effects induced by the drug candidates residing within it. As a result, nanomedicine propounds the assurance towards the improved bioavailability of anticancer drug candidates, increased dose responses, and enhanced targeted efficiency towards delivery and distribution of effective therapeutic concentration, limiting toxic concentration. These aspects emanate the proficiency of drug delivery mechanisms. Understanding the potential tumor targeting barriers and limiting conditions for nanomedicine extravasation, tumor penetration, and final accumulation of the anticancer drug to tumor mass, experiments with in vivo animal models for nanomedicine screening are a key step before it reaches clinical translation. Although the study with animals is undoubtedly valuable, it has many associated ethical issues. Moreover, individual experiments are very expensive and take a longer time to conclude. To overcome these issues, nowadays, multicellular tumor spheroids are considered a promising in vitro model system that proposes better replication of in vivo tumor properties for the future development of new therapeutics. In this review, we will discuss how tumor spheroids could be used as an in vitro model system to screen nanomedicine used in targeted drug delivery, aiming for better therapeutic benefits. In addition, the recent proliferation of mathematical modeling approaches gives profound insight into the underlying physical principles and produces quantitative predictions. The hierarchical tumor structure is already well decorous to be treated mathematically. To study targeted drug delivery, mathematical modeling of tumor architecture, its growth, and the concentration gradient of oxygen are the points of prime focus. Not only are the quantitative models circumscribed to the spheroid, but also the role of modeling for the nanoparticle is equally inevitable. Abundant mathematical models have been set in motion for more elaborative and meticulous designing of nanomedicine, addressing the question regarding the objective of nanoparticle delivery to increase the concentration and the augmentative exposure of the therapeutic drug molecule to the core. Thus, to diffuse the dichotomy among the chemistry involved, biological data, and the underlying physics, the mathematical models play an indispensable role in assisting the experimentalist with further evaluation by providing the admissible quantitative approach that can be validated. This review will provide an overview of the targeted drug delivery mechanism for spheroid, using nanomedicine as an advantageous tool.

Transferrin receptors/magnetic resonance dual-targeted nanoplatform for precise chemo-photodynamic synergistic cancer therapy

Various drug delivery strategies to improve cancer therapeutic efficacy have been actively investigated. One major challenge is to improve the targeting ability. Here elaborately designed nanocarriers (NCs) named as Tf-5-ALA-PTX-NCs are demonstrated to address this problem. In this nanostructure, paclitaxel (PTX) and 5-aminolevulinic acid (5-ALA) were co-encapsulated within magnetic nanocarriers to achieve synergistic chemotherapy and photodynamic therapy, while transferrin (Tf) was conjugated with modified copolymer Pluronic P123 and embedded in the surface of the nanocarriers, which endows nanocarriers with Tf targeting and magnetic targeting to enhance the anti-tumor outcome. Results demonstrated that Tf-5-ALA-PTX-NCs significantly enhanced the targeting drug delivery to MCF-7 cells and synergistically induced apoptosis and death of MCF-7 cells in vitro and highly efficient tumor ablation in vivo. Intriguingly, Tf-5-ALA-PTX-NCs have a controllable "on/off" switch to enhance the drug release. The dual-targeted nanocarriers would be a promising versatile anti-tumor drug delivery and imaging-guided cancer chemo-photodynamic synchronization therapy strategy.

Brefeldin A delivery nanomicelles in hepatocellular carcinoma therapy: Characterization, cytotoxic evaluation in vitro, and antitumor efficiency in vivo

Hepatocellular carcinoma (HCC) is one of the major cancers with high mortality rate. Traditional drugs used in clinic are usually limited by the drug resistance and side effect and novel agents are still needed. Macrolide brefeldin A (BFA) is a well-known lead compound in cancer chemotherapy, however, with poor solubility and instability. In this study, to overcome these disadvantages, BFA was encapsulated in mixed nanomicelles based on TPGS and F127 copolymers (M-BFA). M-BFA was conferred high solubility, colloidal stability, and capability of sustained release of intact BFA. In vitro, M-BFA markedly inhibited the proliferation, induced G0/G1 phase arrest, and caspase-dependent apoptosis in human liver carcinoma HepG2 cells. Moreover, M-BFA also induced autophagic cell death via Akt/mTOR and ERK pathways. In HepG2 tumor-bearing xenograft mice, indocyanine green (ICG) as a fluorescent probe loaded in M-BFA distributed to the tumor tissue rapidly, prolonged the blood circulation, and improved the tumor accumulation capacity. More importantly, M-BFA (10 mg/kg) dramatically delayed the tumor progression and induced extensive necrosis of the tumor tissues. Taken together, the present work suggests that M-BFA has promising potential in HCC therapy.

Fabrication and Characterization of Paclitaxel and Resveratrol Loaded Soluplus Polymeric Nanoparticles for Improved BBB Penetration for Glioma Management

Gliomas are one of the prominent cancers of the central nervous system with limited therapeutic modalities. The present investigation evaluated the synergistic effect of paclitaxel (PAX) and resveratrol (RESV)-loaded Soluplus polymeric nanoparticles (PNPs) against glioma cell lines along with in vivo pharmacokinetics and brain distribution study. PAX-RESV-loaded PNPs were prepared by the thin film hydration technique and optimized for different dependent and independent variables by using DoE (Design-Expert) software. The in vitro physiochemical characterization of prepared PAX-RESV-loaded PNPs exhibited appropriate particle size, PDI and % encapsulation efficiency. Cytotoxicity assay revealed that PTX-RESV loaded PNPs had a synergistic antitumor efficacy against C6 glioma cells compared with single and combined pure drugs. Finally, the pharmacokinetic and brain distribution studies in mice demonstrated that the PNPs significantly enhanced the bioavailability of PTX-RESV PNPs than pure PAX and RESV. Thus, the study concluded that PAX-RESV PNPs combination could significantly enhance anti-glioma activity, and this could be developed into a potential glioma treatment strategy.

PEGylated phospholipid micelles containing D-α-tocopheryl succinate as multifunctional nanocarriers for enhancing the antitumor efficacy of doxorubicin

The aim of this investigation is to clarify the effect of D-α-tocopheryl succinate (vitamin E succinate, VES) and distearoylphosphatidyl ethanolamine-poly(ethylene glycol) (DSPE-PEG) on the encapsulation and controlled release of doxorubicin (DOX) in nano-assemblies and their consequences on the anti-tumor efficacy of DOX. DOX molecules were successfully loaded into the hybrid micelles with VES and DSPE-PEG (VDPM) via thin-film hydration method, exhibiting a small hydrodynamic particle size (~30 nm) and a weak negative zeta potential of around -5 mv. The obtained DOX-loaded VDPM2 displayed retarded DOX release at pH of 7.4, while substantially accelerated drug release at acidic pH of 5.0. Furthermore, the DOX-loaded VDPM2 exhibited substantially slower drug release rate at pH 7.4 compared with the drug-loaded VDPM1 or DPM preparation, benefiting for decreasing the premature DOX release during blood circulation. In vitro cell experiment indicated that DOX-loaded micelles (DPM, VDPM1 and VDPM2) improved the cellular uptake of DOX in 4T1 and MDA-MB-231 cells. The existence of VES component in the structure of DOX-loaded micelles had no obvious influence on the subcellular distribution of the encapsulated DOX molecules. Furthermore, the DOX-loaded VDPM2 exhibited more pronounced cytotoxicity to 4T1 and MDA-MB-231 cancerous cells compared with DOX-loaded DPM and free DOX solution. The hybrid nanocarriers including VES and DSPE-PEG selectively induced intracellular ROS accumulation and increased level of cytoplasmic calcium ion in cancerous cells by interacting with mitochondria and endoplasmic reticulum, bringing about the improved cytotoxicity of DOX. In vivo antitumor efficacy investigation of DOX-loaded VDPM2 against 4T1 xenograft-bearing mice displayed satisfied therapeutic activity with negligible systemic toxicity, as evidenced by the histological analysis and change of body weight. The proposed DOX-loaded VDPM preparation, as a mulifunctional chemotherapeutic nanomedicine system, holds great potential and bright prospect for clinical tumor therapy.

TPGS-Galactose-Modified Polydopamine Co-delivery Nanoparticles of Nitric Oxide Donor and Doxorubicin for Targeted Chemo-Photothermal Therapy against Drug-Resistant Hepatocellular Carcinoma

The lack of cancer cell specificity and the occurrence of multidrug resistance (MDR) are two major obstacles in the treatment of hepatocellular carcinoma (HCC). To tackle these challenges, a novel nanoparticle (NP)-based drug delivery system (DDS) with a core/shell structure consisted of d-α-tocopheryl polyethylene glycol 1000 succinate (TPGS)-galactose (Gal)/polydopamine (PDA) is fabricated. The NP is loaded with doxorubicin (DOX) and a nitric oxide (NO) donor N,N'-di-sec-butyl-N,N'-dinitroso-1,4-phenylenediamine (BNN) sensitive to heat to afford NO-DOX@PDA-TPGS-Gal. The unique binding of Gal to asialoglycoprotein receptor (ASGPR) and the pH-sensitive degradation of NP ensure the targeted transportation of NP into liver cells and the release of DOX in HCC cells. The near-infrared (NIR) light further facilitates DOX release and initiates NO generation from BNN due to the photothermal property of PDA. In addition to the cytotoxicity contributed by DOX, NO, and heat, TPGS and NO act as MDR reversal agents to inhibit P-glycoprotein (P-gp)-related efflux of DOX by HepG2/ADR cells. The combined chemo-photothermal therapy (chemo-PTT) by NO-DOX@PDA-TPGS-Gal thus shows potent anti-cancer activity against drug-resistant HCC cells in vitro and in vivo and significantly prolongs the life span of drug-resistant tumor-bearing mice. The present work provides a useful strategy for highly targeted and MDR reversal treatment of HCC.

Adjudin-loaded redox-sensitive paclitaxel-prodrug micelles for overcoming multidrug resistance with efficient targeted Colon cancer therapy

Multidrug resistance (MDR) is the primary cause for the failure of chemotherapy in the treatment of colon cancer. Recent research has indicated that the combination of a chemotherapeutic agent and a mitochondrial inhibitor might represent a promising strategy to help overcome MDR. However, for this approach to be clinically effective, it is important that the two drugs can be actively and simultaneously delivered into tumor cells at an optimal ratio and completely released drug within cells. To address these challenges, we designed and prepared a folate receptor-targeted and redox-responsive drug delivery system (FA-ss-P/A) that was able to co-deliver paclitaxel (PTX) and adjudin (ADD) to reverse colon cancer MDR. The PTX prodrug was obtained by conjugating PTX to dextrin via a disulfide-linkage. Then, folic acid (FA) was modified on the PTX prodrug. Finally, ADD, a mitochondrial inhibitor, was encapsulated in the PTX prodrug-formed micelles. A series of in vitro and in vivo experiments subsequently demonstrated that FA-ss-P/A can effectively reverse MDR by increasing cell uptake, inhibiting PTX efflux, and improving drug release.

Progress in the study of D-α-tocopherol polyethylene glycol 1000 succinate (TPGS) reversing multidrug resistance

Currently, multidrug resistance (MDR) is one of the major reasons for failure in clinical cancer chemotherapy. Overexpression of the ATP binding cassette (ABC) transporter P-glycoprotein (P-gp), which significantly increases the efflux of anticancer drugs from tumor cells, enhances MDR. In the past few decades, four generations of P-gp inhibitors have appeared. However, they are limited in clinical application due to their severe toxic side effects. As a P-gp inhibitor and carrier for loading chemotherapy agents, TPGS has received increasing attention due to its advantages and unique properties of reversing MDR. TPGS is an amphipathic agent that increases the solubility of most chemotherapy drugs and decreases severe side effects. In addition, TPGS is an excellent carrier with P-gp-inhibiting ability. In this review, we summarize the latest articles on TPGS-based nanodelivery systems to prevent MDR.

TPGS and chondroitin sulfate dual-modified lipid-albumin nanosystem for targeted delivery of chemotherapeutic agent against multidrug-resistant cancer

Multidrug resistance (MDR) remains the primary issue leading to the failure of chemotherapy. In this study, a d-α-tocopherol polyethylene 1000 glycol succinate (TPGS) and chondroitin sulfate (CS) dual-modified lipid-albumin nanosystem was constructed for targeted delivery of paclitaxel (PTX) in treating MDR cancer. The obtained nanosystem (TLA/PTX@CS) had an average size of around 176 nm and a negative zeta potential of around -18 mV. TPGS was confirmed to improve the intracellular accumulation of PTX and facilitate the mitochondrial-targeting of lipid-albumin nanosystem. Functionalized with the outer CS shell, TLA/PTX@CS entered MDR breast cancer (MCF-7/MDR) cells via CD44 receptor-mediated endocytosis. CS shell was degraded by concentrated hyaluronidase in the lysosomes, thereby releasing PTX into cytoplasm and inhibiting cell proliferation. In vivo studies revealed that TLA/PTX@CS possessed prolonged blood circulation, resulting in elevated tumor accumulation, excellent antitumor efficacy with a tumor inhibition ratio of 75.3%, and significant survival benefit in MCF-7/MDR tumor-bearing mice. Hence, this TPGS and CS dual-modified lipid-albumin nanosystem provides a promising strategy for targeted delivery of chemotherapeutic drug and reversal of MDR in cancer treatment.

Near-infrared light-triggered nanobomb for in situ on-demand maximization of photothermal/photodynamic efficacy for cancer therapy

Currently, the in situ on/off switch of PTT/PDT reagents for tumor treatment has evoked considerable interest in the field of cancer therapy. However, the actual PTT/PDT therapy efficacy in tumor treatment is largely restricted by the PTT/PDT reagents' aggregation issues during their release from the hydrophobic carrier to the hydrophilic tumor microenvironment. Thus, it remains a challenge to break through the therapy barrier caused by the PTT/PDT agent aggregation and achieve substantial improvement of anticancer efficacy. In this work, we developed a novel near-infrared (NIR) light-responsive and gas bubble-generated liposomal nanobomb (Cy/Ce6/CO2-Lip-FA) through the co-encapsulation of PTT/PDT reagents with gas precursor into the hydrophobic and hydrophilic regions of liposomes, respectively, in order to overcome the aggregation issues and substantially improve the synergistic PTT/PDT efficacy. Upon arrival at the tumor region, the PS phototoxicity of Cy/Ce6/CO2-Lip-FA could be effectively switched on through CO2 generation induced by the PTT effect of Cypate upon NIR irradiation. The gas bubble burst can remarkably suppress the aggregation of Cypate/Ce6 and extremely enhance the synergistic PTT/PDT efficacy. These results indicate that the proposed NIR-responsive and gas bubble-functionalized liposomal nanobomb is a highly promising platform for tumor treatment with better therapeutic efficacy.

Targeted nanoformulation of C1 inhibits the growth of KB spheroids and cancer stem cell-enriched MCF-7 mammospheres

C1, a synthetic analog of curcumin, has been reported to show potent antiproliferative effects against a variety of cancer cells. Here, we report a strong anticancer activity of the folate receptor-targeted lipid nanoparticle formulation of C1 against cancer cells and cancer stem cells both in 2D culture and 3D spheroids. The size of the C1 encapsulated folic acid functionalized nanoliposomes (Lipos-C1) was determined to be 83 ± 17 nm. Lipos-C1 nanoparticles displayed sustained C1 release kinetics at both pH 7.4 and 5.5. The folate receptor (FR) targeted nanoliposomes were internalized into FR-positive KB cells via the folate receptor-mediated endocytosis process. Lipos-C1 killed KB cells much more efficiently than C1. Lipos-C1 depolymerized microtubules, generated ROS, caused DNA damage, and induced apoptosis in KB cells. Importantly, Lipos-C1 strongly inhibited the growth of the 3D KB spheroids than C1. Interestingly, Lipos-C1 also suppressed cancer stem cells (CSCs) enriched MCF-7 mammosphere growth by impeding breast cancer stem cells (BCSCs) enrichment, growth, and proliferation. The results suggested that Lipos-C1 could be a promising nanoformulation for cancer chemotherapy.

Preparation and antitumor evaluation of hinokiflavone hybrid micelles with mitochondria targeted for lung adenocarcinoma treatment

Hinokiflavone (HF) is a natural biflavonoid extracted from medicinal plants such as Selaginella tamariscina and Platycladus orientalis. HF plays a crucial role in the treatment of several cancers. However, its poor solubility, instability, and low bioavailability have limited its use. In this study, soluplus/d-α-tocopherol acid polyethylene glycol 1000 succinate (TPGS)/dequalinium (DQA) was applied to improve the solubilization efficiency and stability of HF. HF hybrid micelles were prepared via thin-film hydration method. The physicochemical properties of micelles, including particle size, zeta potential, encapsulation efficiency, drug loading, CMC value, and stability were investigated. The in vitro cytotoxicity assay showed that the cytotoxicity of the HF hybrid micelles was higher than that of free HF. In addition, the HF hybrid micelles improved anticancer efficacy and induced mitochondria-mediated apoptosis, which is associated with the high levels of ROS inducing decreased mitochondrial membrane potential, promoting apoptosis of tumor cells. Furthermore, in vivo tumor suppression, smaller tumor volume and increased expression of pro-apoptotic proteins were found in nude mice treated with HF hybrid micelles, suggesting that HF hybrid micelles had stronger tumor suppressive activity compared with free HF. In summary, HF hybrid micelles developed in this study enhanced antitumor effect, which may be a potential drug delivery system for the treatment of lung adenocarcinoma.

Gadolinium-loaded calcium phosphate nanoparticles for magnetic resonance imaging of orthotopic hepatocarcinoma and primary hepatocellular carcinoma

The development of magnetic resonance imaging (MRI) contrast agents with high sensitivity and good biocompatibility is of great value for the diagnosis of primary hepatocellular carcinoma (HCC). Here, a novel MRI contrast agent based on calcium phosphate (CaP) nanoparticles modified with a liver cancer cell targeting peptide A54 (A54-CaP) was fabricated. The T1-positive contrast agent Gd-DTPA was encapsulated inside the nanoparticles (A54-CaPNPs), with a mean diameter of 30 nm and a high encapsulation efficiency of 92.73%. The A54-CaPNP solution exhibited higher longitudinal relaxivity (6.07 mM-1 s-1) than that of the clinically used MRI contrast agent Gd-DTPA (3.56 mM-1 s-1). A much higher accumulation of the nanoparticles in the liver cells was observed, which was directed by the A54 targeting peptide. Furthermore, the MRI diagnostic efficiency of A54-CaPNPs was systematically investigated in an orthotopic liver cancer model and primary HCC model. In vivo MRI experiments showed that A54-CaPNPs had higher sensitivity in the BEL-7402 orthotopic liver cancer model with a more remarkable contrast enhancement and a longer imaging time compared to those without A54 modification. Moreover, the experiments on primary HCC models suggested that A54-CaPNPs showed greatly enhanced MR imaging performance in comparison with Gd-DTPA. These results suggest that A54-CaPNPs possess great potential to enable the non-invasive early diagnosis of primary HCC for timely surgical resection.

TPGS2k-PLGA composite nanoparticles by depleting lipid rafts in colon cancer cells for overcoming drug resistance

Recently, studies showed that the drug-resistant cell membranes have formed high-density lipid rafts regions; traditional targeted drug delivery systems can hardly break through the hard shell and deliver drugs to drug-resistant cells. Here, α-tocopherol polyethylene glycol 2000 succinate (TPGS_2k) was successfully synthesized and used to modify poly (lactic-glycolic acid) nanoparticles co-loaded with doxorubicin (DOX) and simvastatin (SV) (SV/DOX@TPGS_2k-PLGA NPs). The purpose of this study is to explore the synergistic effect between SV consuming cholesterol in lipid rafts and directly down-regulating P-gp expression on the intracellular drugs retention. The research highlights these nanoparticles interrupted lipid rafts (cholesterol-rich domains, where P-gp is often located), which inhibited drug efflux by down-regulating P-gp, promoted the mitochondria apoptosis and made SW620/AD300 cells (DOX-resistant colon cancer cell line) re-sensitized to DOX. Therefore, the carrier can become a promising SV-based nano-delivery system with depleting cholesterol in lipid rafts to reverse drug resistance.

Interfacial properties and micellization of triblock poly(ethylene glycol)-poly(ε-caprolactone)-polyethyleneimine copolymers

This study aimed to explore the link between block copolymers' interfacial properties and nanoscale carrier formation and found out the influence of length ratio on these characters to optimize drug delivery system. A library of diblock copolymers of PEG-PCL and triblock copolymers with additional PEI (PEG-PCL-PEI) were synthesized. Subsequently, a systematic isothermal investigation was performed to explore molecular arrangements of copolymers at air/water interface. Then, structural properties and drug encapsulation in self-assembly were investigated with DLS, SLS and TEM. We found the additional hydrogen bond in the PEG-PCL-PEI contributes to film stability upon the hydrophobic interaction compared with PEG-PCL. PEG-PCL-PEI assemble into smaller micelle-like (such as PEG-PCL4006-PEI) or particle-like structure (such as PEG-PCL8636-PEI) determined by their hydrophilic and hydrophobic block ratio. The distinct structural architectures of copolymer are consistent between interface and self-assembly. Despite the disparity of constituent ratio, we discovered the arrangement of both chains guarantees balanced hydrophilic-hydrophobic ratio in self-assembly to form stable construction. Meanwhile, the structural differences were found to have significant influence on model drugs incorporation including docetaxel and siRNA. Taken together, these findings indicate the correlation between molecular arrangement and self-assembly and inspire us to tune block compositions to achieve desired nanostructure and drug loading.

Recent Advances of D-α-tocopherol Polyethylene Glycol 1000 Succinate Based Stimuli-responsive Nanomedicine for Cancer Treatment

D-α-tocopherol polyethylene glycol 1000 succinate (TPGS) is a pharmaceutical excipient approved by Chinese NMPA and FDA of USA. It's widely applied as a multifunctional drug carrier for nanomedicine. The advantages of TPGS include P-glycoprotein (P-gp) inhibition, penetration promotion, apoptosis induction via mitochondrial-associated apoptotic pathways, multidrug resistant (MDR) reversion, metastasis inhibition and so on. TPGS-based drug delivery systems which are responding to external stimulus can combine the inhibitory functions of TPGS towards P-gp with the environmentally responsive controlled release property and thus exerts a synergistic anti-cancer effect, through increased intracellular drug concentration in tumors cells and well-controlled drug release behavior. In this review, TPGS-based nano-sized delivery systems responsive to different stimuli were summarized and discussed, including pH-responsive, redoxresponsive and multi-responsive systems in various formulations. The achievements, mechanisms and different characteristics of TPGS-based stimuli-responsive drug-delivery systems in tumor therapy were also outlined.

Muscone/RI7217 co-modified upward messenger DTX liposomes enhanced permeability of blood-brain barrier and targeting glioma

Rationale: The dual-targeted drug delivery system was designed for enhancing permeation of the blood-brain barrier (BBB) and providing an anti-glioma effect. As transferrin receptor (TfR) is over-expressed by the brain capillary endothelial (hCMEC/D3) and glioma cells, a mouse monoclonal antibody, RI7217, with high affinity and selectivity for TfR, was used to study the brain targeted drug delivery system. Muscone, an ingredient of traditional Chinese medicine (TCM) musk, was used as the "guide" drug to probe the permeability of the BBB for drug delivery into the cerebrospinal fluid. This study investigated the combined effects of TCM aromatic resuscitation and modern receptor-targeted technology by the use of muscone/RI7217 co-modified docetaxel (DTX) liposomes for enhanced drug delivery to the brain for anti-glioma effect. Methods: Cellular drug uptake from the formulations was determined using fluorescence microscopy and flow cytometry. The drug penetrating ability into tumor spheroids were visualized using confocal laser scanning microscopy (CLSM). In vivo glioma-targeting ability of formulations was evaluated using whole-body fluorescent imaging system. The survival curve study was performed to evaluate the anti-glioma effect of the formulations. Results: The results showed that muscone and RI7217 co-modified DTX liposomes enhanced uptake into both hCMEC/D3 and U87-MG cells, increased penetration to the deep region of U87-MG tumor spheroids, improved brain targeting in vivo and prolonged survival time of nude mice bearing tumor. Conclusion: Muscone and RI7217 co-modified DTX liposomes were found to show improved brain targeting and enhanced the efficacy of anti-glioma drug treatment in vivo.

Solanesol derived therapeutic carriers for anticancer drug delivery

Metabolites of a large number of inert drug carriers can cause long-term exogenous biological toxicity. Therefore, carriers with simultaneous therapeutic effects may be a good choice for drug delivery. Herein, a series of pharmacologically active solanesol derivatives were synthesized and investigated for use as micellar drug carriers for cancer therapy. Solanesyl thiosalicylic acid (STS) was first synthesized by introducing a thiosalicylic acid group to solanesol, inspired by the characteristic structure of farnesyl thiosalicylic acid (FTS) which is a non-toxic inhibitor of all active forms of the RAS protein. Then, two amphiphilic derivatives of STS were formed with ester- and hydrazone (HZ)-bond linked methyl poly(ethylene glycol)(mPEG), mPEG-STS and mPEG-HZ-STS, respectively. The PEGylated STS could be formed stable nano-sized micelles loaded with Doxorubicin (DOX). In vitro, DOX loaded mPEG-STS and mPEG-HZ-STS micelles exhibited stronger tumor inhibition ability compared with free DOX. In vivo, blank mPEG-STS and mPEG-HZ-STS micelles showed an obvious inhibiting effect on tumor growth while the drug loaded micelles had the greatest tumor inhibition effect. The enhanced therapeutic effects and the synergistic effect observed with this solanesol-based drug delivery system could be attributed to the inherent therapeutic qualities of the drug carriers.

The Application of Nanotechnology in the Codelivery of Active Constituents of Plants and Chemotherapeutics for Overcoming Physiological Barriers during Antitumor Treatment

Antitumor therapy using a combination of drugs has shown increased clinical efficacy. Active constituents derived from plants can offer several advantages, such as high efficiacy, low toxicity, extensive effects, and multiple targets. At present, the combination of plants' active constituents and chemotherapeutic drugs has attracted increased attention. Nanodrug delivery systems (NDDSs) have been widely used in tumor-targeted therapy because of their efficacy of delivering antitumor drugs. The in vivo process of tumor-targeted NDDSs has several steps. They include blood circulation, tumor accumulation and penetration, target cell internalization and uptake, and drug release and drug response. In each step, NDDSs encounter multiple barriers that prevent their effective delivery to target sites. Studies have been performed to find alternative strategies to overcome these barriers. We reviewed the recent progress of codelivery of active constituents of plants and chemotherapeutics using NDDSs. Progress into transversing the physiological barriers for more effective in vivo antitumor delivery will be discussed in this review.

Surface engineering of nanomaterials with phospholipid-polyethylene glycol-derived functional conjugates for molecular imaging and targeted therapy

In recent years, phospholipid-polyethylene glycol-derived functional conjugates have been widely employed to decorate different nanomaterials, due to their excellent biocompatibility, long blood circulation characteristics, and specific targeting capability. Numerous in vivo studies have demonstrated that nanomedicines peripherally engineered with phospholipid-polyethylene glycol-derived functional conjugates show significantly increased selective and efficient internalization by target cells/tissues. Targeting moieties including small-molecule ligands, peptides, proteins, and antibodies are generally conjugated onto PEGylated phospholipids to decorate liposomes, micelles, hybrid nanoparticles, nanocomplexes, and nanoemulsions for targeted delivery of diagnostic and therapeutic agents to diseased sites. In this review, the synthesis methods of phospholipid-polyethylene glycol-derived functional conjugates, biophysicochemical properties of nanomedicines decorated with these conjugates, factors dominating their targeting efficiency, as well as their applications for in vivo molecular imaging and targeted therapy were summarized and discussed.

Enhanced anticancer effect of doxorubicin by TPGS-coated liposomes with Bcl-2 siRNA-corona for dual suppression of drug resistance

Multiple drug resistance (MDR) is a tough problem in developing hepatocellular carcinoma (HCC) therapy. Here, we developed TPGS-coated cationic liposomes with Bcl-2 siRNA corona to load doxorubicin (Dox) i.e., Bcl-2 siRNA/Dox-TPGS-LPs, to enhance anticancer effect of Dox in HCC-MDR. TPGS i.e., d-α-tocopheryl polyethylene glycol 1000 succinate, inhibited P-glycoprotein (P-gp) efflux pump and Bcl-2 siRNA suppressed anti-apoptotic Bcl-2 protein. The Bcl-2 siRNA loaded in the liposomal corona was observed under transmission electron microscopy. The stability and hemolysis evaluation demonstrated Bcl-2 siRNA/Dox-TPGS-LPs had good biocompatibility and siRNA-corona could protect the liposomal core to avoid the attachment of fetal bovine serum. In drug-resistant cells, TPGS effectively prolonged intracellular Dox retention time and siRNA-corona did improve the internalization of Dox from liposomes. In vitro and in vivo anticancer effect of this dual-functional nanostructure was examined in HCC-MDR Bel7402/5-FU tumor model. MTT assay confirmed the IC₅₀ value of Dox was 20–50 fold higher in Bel7402/5-FU MDR cells than that in sensitive Bel7402 cells. Bcl-2 siRNA corona successfully entered the cytosol of Bel7402/5-FU MDR cells to downregulate Bcl-2 protein levels in vitro and in vivo. Bcl-2 siRNA/Dox-TPGS-LPs showed superior to TPGS- (or siRNA-) linked Dox liposomes in cell apoptosis and cytotoxicity assay in Bel7402/5-FU MDR cells, and 7-fold greater effect than free Dox in tumor growth inhibition of Bel7402/5-FU xenograft nude mice. In conclusion, TPGS-coated cationic liposomes with Bcl-2 siRNA corona had the capacity to inhibit MDR dual-pathways and subsequently improved the anti-tumor activity of the chemotherapeutic agent co-delivered to a level that cannot be achieved by inhibiting a MDR single way.

A multi-functionalized nanocomposite constructed by gold nanorod core with triple-layer coating to combat multidrug resistant colorectal cancer

Multi-drug resistance (MDR) remains the main culprit for the low survival rate of advanced colorectal cancer (CRC). Photothermal-therapy (PPT) is effective to kill MDR tumor cells, but fails to completely eradicate tumors. In this study, we prepared a nanocomposite based on gold nanorod core with triple layer coating (GNRs/mSiO₂/PHIS/TPGS/DOX) to combat multidrug resistant (MDR) colorectal cancer via multi-strategies. We first synthesized the mesoporous silica-coated gold nanorods (GNRs/mSiO₂), and loaded with antitumor drug doxorubicin (DOX) to realize a combination of chemo- and photothermal-therapy. To reverse DOX resistance, pH responsive poly-histidine (PHIS) was conjugated on GNRs/mSiO₂ to increase drug intracellular accumulation via efficient endo/lysosome escape; d-α-tocopherol polyethylene glycol 1000 succinate (TPGS) was then assembled on the surface of the particles to realize drug intracellular retention by inhibition P-glycoprotein. The results showed that the nanocomposite exhibited a highly efficient photothermal conversion in the NIR region, a pH and NIR triggered drug release profile and an increment of DOX intracellular accumulation and cytotoxicity on MDR SW620/Ad300 cells. Most importantly, the nanocomposite showed the most potent antitumor efficacy without obvious systemic toxicity comparing to other control groups with either chemo- or photothermal therapy alone on SW620/Ad300 tumor bearing mice. Altogether, the successful preparation of the nanocomposite and its potent efficacy might provide evidence for the future design and develop of nano-therapeutic system in the treatment of MDR colorectal cancer.

Peptide and non-peptide mimetics as potential therapeutics targeting oral bacteria and oral biofilms

The development of the oral biofilm requires a complex series of interactions between host tissues and the colonizing bacteria as well as numerous interspecies interactions between the organisms themselves. Disruption of normal host-microbe homoeostasis in the oral cavity can lead to a dysbiotic microbial community that contributes to caries or periodontal disease. A variety of approaches have been pursued to develop novel potential therapeutics that are active against the oral biofilm and/or target specific oral bacteria. The structure and function of naturally occurring antimicrobial peptides from oral tissues and secretions as well as external sources such as frog skin secretions have been exploited to develop numerous peptide mimetics and small molecule peptidomimetics that show improved antimicrobial activity, increased stability and other desirable characteristics relative to the parent peptides. In addition, a rational and minimalist approach has been developed to design small artificial peptides with amphipathic α-helical properties that exhibit potent antibacterial activity. Furthermore, with an increased understanding of the molecular mechanisms of beneficial and/or antagonistic interspecies interactions that contribute to the formation of the oral biofilm, new potential targets for therapeutic intervention have been identified and both peptide-based and small molecule mimetics have been developed that target these key components. Many of these mimetics have shown promising results in in vitro and pre-clinical testing and the initial clinical evaluation of several novel compounds has demonstrated their utility in humans.

TPGS-grafted and acid-responsive soy protein nanogels for efficient intracellular drug release, accumulation, penetration in 3D tumor spheroids of drug-resistant cancer cells

The frequent occurrence of multidrug resistance (MDR) in solid tumors is the major obstacle for nano-drug delivery systems (nDDS) to realize the successful cancer chemotherapy. Herein, we had prepared pH-responsive nanogels via cross-linking TPGS-grafted soy protein with an acid-labile ortho ester cross-linker (OEAM) to realize the efficient intracellular drugs release and accumulation, and subsequently enhance therapeutic effect in MDR tumor cells. These nanogels displayed a uniform size (~200 nm) and morphology, and the introduction of ortho ester bonds endowed nanogels stability in neutral environment and acid-degradability in acidic conditions. Cisplatin (CDDP) was successfully loaded into nanogels, which exhibited an accelerated drug release at low pH. The modification of TPGS efficiently improved cellular internalization and drug accumulation in A549/DDP cells by inhibiting the function of drug efflux pumps (MRP2 and ATP7A/7B), leading to higher cytotoxicity and apoptosis. Moreover, TPGS-grafted nanogels also showed better drug accumulation and penetration in tumor-like spheroids, and then remarkably inhibited tumor growth owing to the rapid drug release in acidic organelles. As a result, the TPGS-grafted and pH-sensitive soy protein nanogels have a great potential as a drugs carrier for the efficient cancer treatment.

Glucose-responsive mesoporous silica nanoparticles to generation of hydrogen peroxide for synergistic cancer starvation and chemistry therapy

Background: The combination of novel starving therapy with chemotherapy is one of the most promising strategies to achieve an effective antitumor activity.

Methods: Herein, we developed a multifunctional mesoporous silica nanoparticle (MSNs-GOx/PLL/HA) coated with poly (L-lysine) (PLL) and hyaluronic acid (HA) for co-delivery of glucose oxidase (GOx) and anticancer drug paclitaxel (PTX) for cancer treatment for the first time. Compared to single chemotherapy, introduction of GOx would not only selectively trigger the consumption of intracellular glucose, leading to the interruption of energy supply, but also elevat the endogenous H₂O₂ level, inducing stronger therapeutic effects.

Results: The novel drug delivery system possessed desirable particle diameter of 40 nm and exhibited a pH-sensitive drug release behavior. An in vitro cellular uptake study indicated that MSNs-GOx/PLL/HA nanoparticles effectively enhanced the cellular uptake of drug in an apparently CD44 receptor-dependent manner, and delivered more cargo into cytoplasm via endolysosomal escape effect in presence of PLL. The nanoplatform has also demonstrated amplified synergistic therapeutic effects for remarkable tumor inhibition in a xenograft animal tumor model.

Conclusion: Consequently, the developed synergistic starving-like/chemotherapy may provide a potential platform for next generation cancer therapy.

Acid-breakable TPGS-functionalized and diallyl disulfide-crosslinked nanogels for enhanced inhibition of MCF-7/ADR solid tumours

Herein, the dual-functionalized nanogels were used for multidrug resistance (MDR) solid tumour therapy by combining ROS with inhibition of efflux.

Photo-induced hydrogen-bonding complexes for drug periodic release

A convenient approach for periodic drug release was accomplished through photo-induced hydrogen-bonding complexation, and then by further disruption upon heating.

Topical anesthesia therapy using lidocaine-loaded nanostructured lipid carriers: tocopheryl polyethylene glycol 1000 succinate-modified transdermal delivery system

Purpose

Transdermal drug delivery of local anesthetics using lipid nanoparticles could enhance lipophilic drugs permeation through the stratum corneum, improve drug diffusion to deeper skin, and exert good therapeutic effects. The purpose of this study was to engineer a Tocopheryl Polyethylene Glycol 1000 Succinate (TPGS)-modified cationic nanostructured lipid carriers (NLC) for the delivery of lidocaine (LID; TPGS/LID-NLC).

Materials and methods

TPGS/LID-NLC was prepared by solvent diffusion method. The particle size, polydispersity index, zeta potential, drug entrapment efficiency, drug loading, stability, drug release, and cytotoxicity were tested to evaluate the basic characters of NLC. In vitro skin permeation and in vivo anesthesia effect in an animal model were further investigated to determine the therapeutic efficiency of the system.

Results

TPGS/LID-NLC had a particle size of 167.6±4.3 nm, a zeta potential of +21.2±2.3 mV, an entrapment efficiency of 85.9%±3.1%, and a drug loading of 11.5%±0.9%. A sustained release pattern was achieved by TPGS/LID-NLC, with 81.2% of LID released at 72 hours. In vitro permeation study showed that the steady-state fluxes (J_ss), permeability coefficient (Kp), and cumulative drug permeation Q_n at 72 hours (Q₇₂) of TPGS/LID-NLC were 15.6±1.8 µg/cm²/hour, 10.3±0.9 cm/hour (×10⁻³), and 547.5±23.6 µg/cm², respectively, which were significantly higher than the nonmodified NLC and free drug groups. In vivo anesthesia effect of TPGS/LID-NLC was the most remarkable and long acting among the formulations tested, which could be concluded by the most considerable maximum possible effect from 10 to 120 minutes during the whole research.

Conclusion

The most prominent in vitro permeation efficiency and in vivo anesthetic effect of TPGS/LID-NLC could be the evidence that TPGS-modified NLC could function as a promising drug delivery system for prolonged and efficient local anesthetic therapy.

Effect of the Folate Ligand Density on the Targeting Property of Folated-Conjugated Polymeric Nanoparticles

Targeted drug delivery systems have attracted increasing attention due to their ability for delivering anticancer drugs selectively to tumor cells. Folic acid (FA)-conjugated targeted block copolymers, FA-Pluronic-polycaprolactone (FA-Pluronic-PCL) are synthesized in this study. The anticancer drug paclitaxel (PTX) is loaded in FA-Pluronic-PCL nanoparticles by nanoprecipitation method. The in vitro release of PTX from FA-Pluronic-PCL nanoparticles shows slow and sustained release behaviors. The effect of FA ligand density of FA-Pluronic-PCL nanoparticles on their targeting properties is examined by both cytotoxicity and fluorescence methods. It is shown that FA-Pluronic-PCL nanoparticles indicated better targeting ability than non-targeted PCL-Pluronic-PCL nanoparticles. Furthermore, FA-F127-PCL nanoparticle with 10% FA molar content has more effective antitumor activity and higher cellular uptake than those with 50% and 91% FA molar content. These results prove that FA-F127-PCL nanoparticle with 10% FA molar content can be a better candidate as the drug carrier in targeted drug delivery systems.

Codelivery of doxorubicin and elacridar to target both liver cancer cells and stem cells by polylactide-co-glycolide/d-alpha-tocopherol polyethylene glycol 1000 succinate nanoparticles

Purpose

Liver cancer is the third leading cause of cancer-related deaths worldwide. Liver cancer stem cells (LCSCs) are a subpopulation of cancer cells that are responsible for the initiation, progression, drug resistance, recurrence, and metastasis of liver cancer. Recent studies have suggested that the eradication of both LCSCs and liver cancer cells is necessary because the conversion of cancer stem cells (CSCs) to cancer cells occasionally occurs. As ATP-binding cassette (ABC) transporters are overexpressed in both CSCs and cancer cells, combined therapies using ABC transporter inhibitors and chemotherapy drugs could show superior therapeutic efficacy in liver cancer. In this study, we developed poly(lactide-co-glycolide)/d-alpha-tocopherol polyethylene glycol 1000 succinate nanoparticles to accomplish the simultaneous delivery of an optimized ratio of doxorubicin (DOX) and elacridar (ELC) to target both LCSCs and liver cancer cells.

Methods

Median-effect analysis was used for screening of DOX and ELC for synergy in liver cancer cells (HepG2 cells) and LCSCs (HepG2 tumor sphere [HepG2-TS]). Then, nanoparticles loaded with DOX and ELC at the optimized ratio (NDEs) were prepared by nanoprecipitation method. The cytotoxicity and colony and tumor sphere formation ability of nanoparticles were investigated in vitro, and the tissue distribution and antitumor activity of nanoparticles were evaluated in vivo.

Results

We demonstrated that a DOX/ELC molar ratio of 1:1 was synergistic in HepG2 cells and HepG2-TS. NDEs were shown to exhibit significantly increased cytotoxic effects against both HepG2 and HepG2-TS compared with DOX-loaded nanoparticles (NDs) or ELC-loaded nanoparticles (NEs) in vitro. In vivo studies demonstrated that the nanoparticles exhibited better tumor targeting, with NDE showing the strongest antitumor activity with lower systemic toxicity.

Conclusion

These results suggested that NDE represented a promising combination therapy against liver cancer by targeting both liver cancer cells and CSCs.

Prior anti-CAFs break down the CAFs barrier and improve accumulation of docetaxel micelles in tumor

BACKGROUND

Abnormal expression of stromal cells and extracellular matrix in tumor stroma creates a tight barrier, leading to insufficient extravasation and penetration of therapeutic agents. Cancer-associated fibroblasts (CAFs) take on pivotal roles encouraging tumor progression.

METHOD

To surmount the refractoriness of stroma, we constructed a multi-targeting combined scenario of anti-CAFs agent tranilast and antitumor agent docetaxel micelles (DTX-Ms). Tranilast cut down crosstalk between tumor cells and stromal cells, ameliorated the tumor microenvironment, and enhanced the antiproliferation efficacy of DTX-Ms on cancer cells.

RESULTS

Diverse experiments demonstrated that tranilast enhanced DTX-Ms' antitumor effect in a two-stage pattern by CAFs ablation, tumor cell migration blocking, and metastasis inhibition. Along with activated CAFs decreasing in vivo, the two-stage therapy succeeded in reducing interstitial fluid pressure, normalizing microvessels, improving micelles penetration and retention, and inhibiting tumor growth and metastasis. Interestingly, tranilast alone failed to inhibit tumor growth in vivo, and it could only be used as an adjuvant medicine together with an antitumor agent.

CONCLUSION

Our proposed two-stage therapy offers a promising strategy to enhance antitumor effects by breaking down CAFs barrier and increasing micellar delivery efficiency.