pH-sensitive polymeric micelles formed by doxorubicin conjugated prodrugs for co-delivery of doxorubicin and paclitaxel

Efficient Strategy to Synthesize Tunable pH-Responsive Hybrid Micelles Based on Iron Oxide and Gold Nanoparticles

The preparation of multifunctional nanomaterials based on inorganic nanoparticles with organic materials has emerged as a promising strategy for the development of new nanomedicines for in vitro and in vivo biomedical applications. Here, we synthesized pH-responsive hybrid inorganic micelles by combining a novel pH-responsive amphiphilic molecule with hydrophobic payloads. This amphiphile was synthesized in a one-pot reaction and self-assembled readily into micelles under acidic pH conditions. In the presence of hydrophobic NP payloads such as AuNPs or IONPs, the amphiphile self-organized around them through hydrophobic interactions, resulting in the formation of colloidally stable hybrid micelles. The size of the hydrophobic NPs determined the pH-response of the inorganic hybrid micelles, which is tuned from pH 7 to 11 for our pH-responsive amphiphilic molecule. This achievement represents a novel approach for the synthesis of tunable pH-responsive hybrid micelles based on inorganic NPs for biomedical imaging, hyperthermia treatment, and also drug delivery nanosystems.

Dendritic Polylysine with Paclitaxel and Triptolide Codelivery for Enhanced Cancer Ferroptosis through the Accumulation of ROS

Recently, paclitaxel (PTX) was reported to increase intracellular lipid reactive oxygen species (ROS) levels, triggering cancer cell ferroptosis. Based on this, some efforts had been made to improve PTX treatment for non-small-cell lung cancer (NSCLC). Our previous studies demonstrated that triptolide (TPL) could improve the antitumor effect of PTX. Nevertheless, the poor solubility and side effects often limit the application of chemotherapy drugs. In this paper, we constructed a novel nanodrug delivery system (NDDS) chemosynthesis by PEGylated generation 3 (G3) dendritic polylysine coloaded with PTX and TPL (PTX-TPL-PEG-PLL, PTPP), which was endowed with the ability of tumor targeting and favorable solubility. In addition, we demonstrated that TPL could induce ROS generation by regulating the NF-κB signaling pathway to enhance the ferroptosis-induced effect of PTX. Besides, ferroptosis induced by PTPP could improve chemoresistance through inhibiting the level of P-gp, GPX4, and SLC7A11. Furthermore, we determined that ferroptosis may strengthen the immune response by increasing the expression of CD8+ T cells and IFN-γ+ cells while decreasing Treg cells. In general, PTPP may be a potential system for NSCLC treatment.

ROS-Responsive Prodrug Micelle Co-Delivery System for Synergistic Antiatherosclerotic Therapy

Tanshinone IIA (TS-IIA) and salvianic acid A (SAA) are the main pharmacological active constituents of Danshen, which exhibit potent effects on atherosclerosis. A combination of TS-IIA and SAA might exert a synergistic antiatherosclerotic effect. However, the opposite solubility profiles of TS-IIA and SAA might lead to difficulty in achieving a synergistic combined effect of the two active components. Therefore, in this work, we fabricated a ROS-responsive prodrug micelle for the codelivery of TS-IIA and SAA (TS-IIA-PM) by self-assembling amphiphilic block copolymer PEG5000-SAA/PLA10000-APBA. The amphiphilic polymer was characterized by 1H NMR, FTIR, and alizarin red S competition tests. The ROS responsiveness of TS-IIA-PM was evidenced by time-course monitoring of particle size and morphology changes and drug release behavior in the presence of 1 mM H2O2. We found TS-IIA-PM was stable according to its critical micelle concentration and the unchanged particle sizes in 10% FBS for 7 days. The results of in vitro and in vivo tests revealed that TS-IIA-PM was safe and biocompatible. Furthermore, it was observed that TS-IIA and prodrug micelle could produce synergistic antiatherosclerotic effect based on the results of the antioxidant study, which was further confirmed by a series of pharmocodynamics studies, such as in vitro DiI-oxLDL uptake study, oil red O staining, cholesterol efflux study, inflammatory cytokine analysis, in vivo CD68 immunostaining, and lipid disposition staining studies. Collectively, TS-IIA-PM holds great potential for the safe and efficient codelivery of TS-IIA and SAA for synergistic antiatherosclerosis.

Recent advances in pH/enzyme-responsive polysaccharide-small-molecule drug conjugates as nanotherapeutics

Now-a-days, the polysaccharides are extensively employed for the delivery of small-molecule drugs ascribed to their excellent biocompatibility, biodegradability and modifiability. An array of drug molecules is often chemically conjugated with different polysaccharides to augment their bio-performances. As compared to their therapeutic precursors, these conjugates could typically demonstrate an improved intrinsic solubility, stability, bioavailability and pharmacokinetic profiles of the drugs. In current years, various stimuli-responsive particularly pH and enzyme-sensitive linkers or pendants are also exploited to integrate the drug molecules into the polysaccharide backbone. The resulting conjugates could experience a rapid molecular conformational change upon exposure to the microenvironmental pH and enzyme changes of the diseased states, triggering the release of the bioactive cargos at the targeted sites and eventually minimize the systemic side effects. Herein, the recent advances in pH and enzyme -responsive polysaccharide-drug conjugates and their therapeutic benefits are systematically reviewed, following a brief description on the conjugation chemistry of the polysaccharides and drug molecules. The challenges and future perspectives of these conjugates are also precisely discussed.

Co-Delivery of paclitaxel and doxorubicin in folate-Targeted pluronic/ploy (D,L-lactide-b-glycolide) polymersomes

Drugs with different solubility can be selectively embedded into polymersomes with the hydrophilic core and hydrophobic bilayer. Novel folate-targeted Pluronic/poly (D,L-lactide-b-glycolide) polymersomes were constructed and used for the co-delivery of paclitaxel (PTX) and doxorubicin (DOX) to improve their inhibitory effect over cancer cells. The particle size of blank polymersomes was mainly distributed below 125 nm. The release of PTX and DOX from polymersomes showed an initial burst release followed by a sustained and slow release. The in vitro cytotoxicity data showed that the targeted co-loaded polymersomes (PTX&DOX FA-Ps) exhibited better inhibitory effect than single-loaded polymersomes and free drugs did. Furthermore, PTX&DOX FA-Ps showed the synergistic therapeutic effect over OVCAR-3 cancer cells. The cellular uptake results also showed that folate modified polymersomes had excellent targeting performance. Therefore, the folate-targeted Pluronic/poly (D,L-lactide-b-glycolide) polymersomes have potential application value as novel drug carriers to co-deliver PTX and DOX.

Guanidine–Curcumin Complex-Loaded Amine-Functionalised Hollow Mesoporous Silica Nanoparticles for Breast Cancer Therapy

The current study focuses on developing a tumour-targeted functionalised nanocarrier that wraps hollow mesoporous silica nanoparticles. The guanidine carbonate and curcumin are immobilised on the surface of 3-aminopropyl-triethoxy silane (APTES)-decorated hollow mesoporous silica nanoparticles (HMSNP), as confirmed through XPS and NMR analysis. XPS analysis demonstrates that the shape of the hysteresis loops is modified and that pore volume and pore diameter are consequently decreased compared to control. Guanidine (85%) and guanidine–curcumin complex (90%) were successfully encapsulated in HMSNAP and showed a 90% effective and sustained release at pH 7.4 for up to 72 h. Acridine orange/ethidium bromide dual staining determined that GuC-HMNSAP induced more late apoptosis and necrosis at 48 and 72 h compared with Gu-HMNSAP-treated cells. Molecular investigation of guanidine-mediated apoptosis was analysed using western blotting. It was found that cleaved caspases, c-PARP, and GSK-3β (Ser9) had increased activity in MCF-7 cells. GuC-HMSNAP increased the activity of phosphorylation of oncogenic proteins such as Akt (Ser473), c-Raf (Ser249), PDK1 (Ser241), PTEN (Ser380), and GSK-3β (Ser9), thus inducing cell death in MCF-7 cells. Altogether, our findings confirm that GuC-HMNSAP induces cell death by precisely associating with tumour-suppressing proteins, which may lead to new therapeutic approaches for breast cancer therapy.

Nanocluster-Based Drug Delivery and Theranostic Systems: Towards Cancer Therapy

Over the last decades, the global life expectancy of the population has increased, and so, consequently, has the risk of cancer development. Despite the improvement in cancer therapies (e.g., drug delivery systems (DDS) and theranostics), in many cases recurrence continues to be a challenging issue. In this matter, the development of nanotechnology has led to an array of possibilities for cancer treatment. One of the most promising therapies focuses on the assembly of hierarchical structures in the form of nanoclusters, as this approach involves preparing individual building blocks while avoiding handling toxic chemicals in the presence of biomolecules. This review aims at presenting an overview of the major advances made in developing nanoclusters based on polymeric nanoparticles (PNPs) and/or inorganic NPs. The preparation methods and the features of the NPs used in the construction of the nanoclusters were described. Afterwards, the design, fabrication and properties of the two main classes of nanoclusters, namely noble-metal nanoclusters and hybrid (i.e., hetero) nanoclusters and their mode of action in cancer therapy, were summarized.

Advances in the therapeutic delivery and applications of functionalized Pluronics: A critical review

Pluronic (PEO-PPO-PEO) block copolymers can form nano-sized micelles with a structure composed of a hydrophobic PPO core and hydrophilic PEO shell layer. Pluronics are U.S. Food and Drug Administration approved polymers, which are widely used for solubilization of drugs and their delivery, gene/therapeutic delivery, diagnostics, and tissue engineering applications due to their non-ionic properties, non-toxicity, micelle forming ability, excellent biocompatibility and biodegradability. Although Pluronics have been employed as drug carrier systems for several decades, numerous issues such as rapid dissolution, shorter residence time in biological media, fast clearance and weak mechanical strength have hindered their efficacy. Pluronics have been functionalized with pH-sensitive, biological-responsive moieties, antibodies, aptamers, folic acid, drugs, different nanoparticles, and photo/thermo-responsive hydrogels. These functionalization strategies enable Pluronics to act as stimuli responsive and targeted drug delivery vehicles. Moreover, Pluronics have emerged in nano-emulsion formulations and have been utilized to improve the properties of cubosomes, dendrimers and nano-sheets, including their biocompatibility and aqueous solubility. Functionalization of Pluronics results in the significant improvement of target specificity, loading capacity, biocompatibility of nanoparticles and stimuli responsive hydrogels for the promising delivery of a range of drugs. Therefore, this review presents an overview of all advancements (from the last 15 years) in functionalized Pluronics, providing a valuable tool for industry and academia in order to optimize their use in drug or therapeutic delivery, in addition to several other biomedical applications.

pH-Sensitive Dextran-Based Micelles from Copper-Free Click Reaction for Antitumor Drug Delivery

There remains a need to develop new strategies to fabricate dextran-based biocompatible drug delivery systems for safe and effective chemotherapy. Herein, a copper-free azide-propiolate ester click reaction was introduced for dextran modification to fabricate a pH-sensitive dextran-based drug delivery system. A pH-sensitive dextran-based micelle system, self-assembled from amphiphilic dextran-graft-poly(2-(diisopropylamino)ethyl methacrylate-co-2-(2',3',5'-triiodobenzoyl)ethyl methacrylate) or dextran-g-P(DPA-co-TIBMA), is reported for effective chemotherapy. The amphiphilic dextran-g-P(DPA-co-TIBMA) was prepared via reversible addition-fragmentation chain-transfer (RAFT) polymerization and copper-free azide-propiolate ester click reaction. Doxorubicin (DOX)-loaded dextran-g-P(DPA-co-TIBMA) micelles were prepared through self-assembly of DOX and dextran-g-P(DPA-co-TIBMA) in aqueous solution, and had a mean diameter of 154 nm and a drug loading content of 9.7 wt %. The release of DOX from DOX-loaded dextran-g-P(PDPA-co-TIBMA) micelles was slow at pH 7.4, but was greatly accelerated under acidic conditions (pH 6 and 5). Confocal laser scanning microscopy and flow cytometry experiments showed that the dextran-g-P(DPA-co-TIBMA) micelles could effectively deliver and release DOX in human breast cancer cell line (MCF-7 cells). MTT assay showed that dextran-g-P(DPA-co-TIBMA) exhibited excellent biocompatibility while DOX-loaded dextran-g-P(DPA-co-TIBMA) micelles have good antitumor efficacy in vitro. The in vivo therapeutic studies indicated that the DOX-loaded dextran-g-P(PDPA-co-TIBMA) micelles could effectively reduce the growth of tumor with little body weight reduction.

Multifunctional polymeric micellar nanomedicine in the diagnosis and treatment of cancer

Polymeric micelles are a prevalent topic of research for the past decade, especially concerning their fitting ability to deliver drug and diagnostic agents. This delivery system offers outstanding advantages, such as biocompatibility, high loading efficiency, water-solubility, and good stability in biological fluids, to name a few. The multifunctional polymeric micellar architect offers the added capability to adapt its surface to meet the looked-for clinical needs. This review cross-talks the recent reports, proof-of-concept studies, patents, and clinical trials that utilize polymeric micellar family architectures concerning cancer targeted delivery of anticancer drugs, gene therapeutics, and diagnostic agents. The manuscript also expounds on the underlying opportunities, allied challenges, and ways to resolve their bench-to-bedside translation for allied clinical applications.

Preparation, development and characterization of Leucaena leucocephala galactomannan (LLG) conjugated sinapic acid: A potential colon targeted prodrug

Sinapic acid (SA), a widely prevalent hydroxycinnamic acid, possess numerous biological activities owing to its antioxidant property. The present study was aimed to prepare colon targeted polysaccharidic/polymeric ester prodrug of SA (a microbially triggered system) using Leucaena leucocephala galactomannan (LLG) as a polysaccharidic carrier. The polymeric conjugates of SA-LLG were found to exhibit an increase in % yield and DS with increase in amount of SA and volume of thionyl chloride. The degree of depolymerization of SA-LLG prodrug batches were evaluated using optimized concentration of galactomannase. The SA-LLG prodrug was characterized employing UV and FTIR spectroscopy, ¹H NMR and XRD. In vitro release study of the optimized prodrug batch (SL10) suggested stable nature of SA-LLG conjugate under acidic (pH 1.2) and alkaline conditions (pH 6.8). The treatment of prodrug with galactomannase (15 mg/mL) followed by esterase (10 U/mL) enzyme released approximately 81% of SA after 24 h. The cell viability results revealed that free SA and SA-LLG were found to have similar antiproliferative potential against human colon cancer cell lines (HCT-116 cells). Our investigation revealed that polysaccharidic prodrug, SA-LLG, has the potential for colon targeting of SA and thus can be employed for the treatment of Inflammatory Bowel Diseases (IBDs).

Recent Advancements in Stimuli Responsive Drug Delivery Platforms for Active and Passive Cancer Targeting

The tumor-specific targeting of chemotherapeutic agents for specific necrosis of cancer cells without affecting the normal cells poses a great challenge for researchers and scientists. Though extensive research has been carried out to investigate chemotherapy-based targeted drug delivery, the identification of the most promising strategy capable of bypassing non-specific cytotoxicity is still a major concern. Recent advancements in the arena of onco-targeted therapies have enabled safe and effective tumor-specific localization through stimuli-responsive drug delivery systems. Owing to their promising characteristic features, stimuli-responsive drug delivery platforms have revolutionized the chemotherapy-based treatments with added benefits of enhanced bioavailability and selective cytotoxicity of cancer cells compared to the conventional modalities. The insensitivity of stimuli-responsive drug delivery platforms when exposed to normal cells prevents the release of cytotoxic drugs into the normal cells and therefore alleviates the off-target events associated with chemotherapy. Contrastingly, they showed amplified sensitivity and triggered release of chemotherapeutic payload when internalized into the tumor microenvironment causing maximum cytotoxic responses and the induction of cancer cell necrosis. This review focuses on the physical stimuli-responsive drug delivery systems and chemical stimuli-responsive drug delivery systems for triggered cancer chemotherapy through active and/or passive targeting. Moreover, the review also provided a brief insight into the molecular dynamic simulations associated with stimuli-based tumor targeting.

Dual-responsive polymersomes as anticancer drug carriers for the co-delivery of doxorubicin and paclitaxel

Multi stimuli-responsive polymersomes are in high demand as smart drug carriers, particularly for the treatment of complex cancers. However, most polymersomes have multi-responsiveness that does not affect each other and focus on single drug loading. Here, we have designed photo-crosslinked temperature and pH dual-responsive polymersomes by the self-assembly of a triblock polymer of methoxyl poly(ethylene glycol)-b-poly(N-isopropylacrylamide)-b-poly[2-(diethylamino)ethyl methacrylate-co-2-hydroxy-4-(methacryloyloxy)benzophenone] (mPEG-b-PNIPAM-b-P(DEAEMA-co-BMA)) synthesized via reversible addition-fragmentation chain transfer polymerization (RAFT). The dual-responsive polymersomes had a layered membrane, resulting in tunable permeability. Importantly, the polymersomes were proved to have a pH-controlled temperature-responsiveness. A hydrophilic-hydrophobic drug pair (doxorubicin hydrochloride, DOX, and paclitaxel, PTX) could be co-encapsulated in the fabricated polymersomes. The membrane permeability based on its layered structure was triggered by the change in temperature and pH to permit the separate control on the release of DOX and PTX. In a simulated tumor microenvironment, DOX and PTX encapsulated in the polymersomes could take effect for a relatively longer period and could work synergistically. Thus, the photo-crosslinked and dual-responsive polymersomes can be considered as promising drug carriers in the field of tumor combination chemotherapy.

An On-Demand pH-Sensitive Nanocluster for Cancer Treatment by Combining Photothermal Therapy and Chemotherapy

Combination therapy is considered to be a promising strategy for improving the therapeutic efficiency of cancer treatment. In this study, an on-demand pH-sensitive nanocluster (NC) system was prepared by the encapsulation of gold nanorods (AuNR) and doxorubicin (DOX) by a pH-sensitive polymer, poly(aspartic acid-graft-imidazole)-PEG, to enhance the therapeutic effect of chemotherapy and photothermal therapy. At pH 6.5, the NC systems formed aggregated structures and released higher drug amounts while sustaining a stable nano-assembly, structured with less systemic toxicity at pH 7.4. The NC could also increase antitumor efficacy as a result of improved accumulation and release of DOX from the NC system at pHex and pHen with locally applied near-infrared light. Therefore, an NC system would be a potent strategy for on-demand combination treatment to target tumors with less systemic toxicity and an improved therapeutic effect.

Biocompatibility of Biomaterials for Nanoencapsulation: Current Approaches

Nanoencapsulation is an approach to circumvent shortcomings such as reduced bioavailability, undesirable side effects, frequent dosing and unpleasant organoleptic properties of conventional drug delivery systems. The process of nanoencapsulation involves the use of biomaterials such as surfactants and/or polymers, often in combination with charge inducers and/or ligands for targeting. The biomaterials selected for nanoencapsulation processes must be as biocompatible as possible. The type(s) of biomaterials used for different nanoencapsulation approaches are highlighted and their use and applicability with regard to haemo- and, histocompatibility, cytotoxicity, genotoxicity and carcinogenesis are discussed.

An ultra-long circulating nanoparticle for reviving a highly selective BCR-ABL inhibitor in long-term effective and safe treatment of chronic myeloid leukemia

Nanotechnology has demonstrated great promise for the development of more effective and safer cancer therapies. We recently developed a highly selective inhibitor of BCR-ABL fusion tyrosine kinase for chronic myeloid leukemia (CML). However, the poor drug-like properties were hurdles to its further clinical development. Herein, we re-investigate it by conjugating an amphiphilic polymer and self-assembling into a nanoparticle (NP) with a high loading (~10.3%). The formulation greatly improved its solubility and drastically extended its circulation half-life from ~5.3 to ~117 h (>20-fold). In the 150 days long-term engraftment model experiment, long intravenous dosing intervals of the NPs (every 4 or 8 days) exhibited much better survival and negligible toxicities as compared to daily oral administration of the inhibitor. Moreover, the NPs showed excellent inhibition of tumor growth in the subcutaneous xenograft model. All results suggest that the ultra-long circulating pro-drug NP may provide an effective and safe therapeutic strategy for BCR-ABL-positive CML.

Novel pH-Sensitive Urushiol-Loaded Polymeric Micelles for Enhanced Anticancer Activity

Purpose

The aim of this study was to develop a means of improving the bioavailability and anticancer activity of urushiol by developing an urushiol-loaded novel tumor-targeted micelle delivery system based on amphiphilic block copolymer poly(ethylene glycol)-b-poly-(β-amino ester) (mPEG-PBAE).

Materials and Methods

We synthesized four different mPEG-PBAE copolymers using mPEG-NH₂ with different molecular weights or hydrophobicity levels. Of these, we selected the mPEG₅₀₀₀-PBAE-C₁₂ polymer and used it to develop an optimized means of preparing urushiol-loaded micelles. Response surface methodology was used to optimize this formulation process. The micellar properties, including particle size, pH sensitivity, drug release dynamics, and critical micelle concentrations, were characterized. We further used the MCF-7 human breast cancer cell line to explore the cytotoxicity of these micelles in vitro and assessed their pharmacokinetics, tissue distribution, and antitumor activity in vivo.

Results

The resulting micelles had a mean particle size of 160.1 nm, a DL value of 23.45%, and an EE value of 80.68%. These micelles were found to release their contents in a pH-sensitive manner in vitro, with drug release being significantly accelerated at pH 5.0 (98.74% in 72 h) without any associated burst release. We found that urushiol-loaded micelles were significantly better at inducing MCF-7 cell cytotoxicity compared with free urushiol, with an IC₅₀ of 1.21 mg/L. When these micelles were administered to tumor model animals in vivo, pharmacokinetic analysis revealed that the total AUC and MRT of these micelles were 2.28- and 2.53-fold higher than that of free urushiol, respectively. Tissue distribution analyses further revealed these micelles to mediate significantly enhanced tumor urushiol accumulation.

Conclusion

The pH-responsive urushiol-loaded micelles described in this study may be ideally suited for clinical use for the treatment of breast cancer.

Phenylboronic acid-functionalized F127-oligochitosan conjugate micelles for doxorubicin encapsulation

Doxorubicin shows good anticancer activity, but poor pharmacokinetic property and high organ toxicity restrict its clinical application. The synthesized phenylboronic acid-modified F127-chitosan conjugate was used to prepare doxorubicin-loaded micelles through dialysis method. The physicochemical properties of the doxorubicin-loaded micelles were characterized. These micelles were further evaluated for in vitro release/cytotoxicity, in vivo activity/biosafety, and pharmacokinetic studies. in vitro release experiment demonstrated that the release of doxorubicin from drug-loaded micelles was pH-dependent. in vitro cytotoxic study showed that the introduction of phenylboronic acid resulted in lower IC₅₀ against B16 cells than that in non-modified F127-chitosan micelles group, and the doxorubicin-loaded micelles displayed lower in vitro activity against B16, A549, and HT-29 cells than free doxorubicin did. However, in vivo experiments confirmed that the doxorubicin-loaded micelles were safe for mouse main organs, obviously improved pharmacokinetic parameters of doxorubicin in rat and achieved comparable inhibition of tumor growth with no animal death in B16-bearing mice models throughout the experiment when compared with free doxorubicin. The phenylboronic acid-sialic acid interaction and pH-sensitive drug release might play important roles in increased tumor targeting and therapeutic effect of the doxorubicin-loaded micelles.

Acid-Responsive and Biologically Degradable Polyphosphazene Nanodrugs for Efficient Drug Delivery

To enhance the therapeutic effects and reduce the damage to normal tissues in cancer chemotherapy, it is indispensable to develop drug delivery carriers with controllable release and good biocompatibility. In this work, acid-responsive and degradable polyphosphazene (PPZ) nanoparticles were synthesized by the reaction of hexachlorotripolyphosphonitrile (HCCP) with 4-hydroxy-benzoic acid (4-hydroxy-benzylidene)-hydrazide (HBHBH) and anticancer drug doxorubicin (DOX). The controlled release of DOX could be realized based on the acid responsiveness of acylhydrazone in HBHBH. Experimental results showed that polyphosphazene nanoparticles remained stable in the body's normal fluids (pH ∼ 7.4), while they were degraded and controllable release of DOX in an acidic environment such as tumors (pH ∼ 6.8) and lysosome and endosome (∼5.0) in cancer cells In particular, the doxorubicin (DOX)-loading ratio was fair high and could be tuned from 10.6 to 52.6% by changing the dosing ratio of DOX to HBHBH. Meanwhile, the polyphosphazene nanodrugs showed excellent toxicity to tumor cells and reduced the side effect to normal cells both in vitro and in vivo due to their enhanced permeability and retention (EPR) effect and pH-sensitive degradation properties. Therefore, the constructed pH-sensitive drug delivery system has great potential for cancer chemotherapy.

Co-delivery of miR-29b and germacrone based on cyclic RGD-modified nanoparticles for liver fibrosis therapy

Hepatic stellate cells (HSCs) were activated and secreted excessive amounts of extracellular matrix (ECM) proteins during pathogenetic progress of liver fibrosis. Germacrone (GMO) and miR-29b can play an important role in inhibiting growth of HSCs and production of type I collagen. GMO and miR-29b were co-encapsulated into nanoparticles (NPs) based on poly(ethylene glycol)-block-poly(lactide-co-glycolide) (PEG-PLGA). Then, NPs were modified with cyclic RGD peptides (cRGDfK). cRGDfK is an effective ligand to bind integrin α_vβ₃ and increase the targeting ability for fibrotic liver. GMO- and miR-29b-loaded NPs exhibited great cytotoxicity to activated HSCs and significantly inhibited production of type I collagen. Liver fibrosis model of mice was induced by administration of carbon tetrachloride. Great targeting ability was achieved in liver fibrotic mice treated with cRGD-modified NPs. Significant ant-fibrotic effects have been presented based on hematoxylin and eosin (H&E), Masson and Sirius Red staining results of liver tissues collected from mice treated with drug-loaded NPs. All these results indicate GMO- and miR-29b-loaded cRGD-modified NPs have the potential for clinical use to treat liver fibrosis.

Ferulic acid grafted self-assembled fructo-oligosaccharide micro particle for targeted delivery to colon

Colorectal cancer is the third most commonly occurring malignancy and is ranked second among the leading cause of cancer death globally. The colorectal cancer is attributed to the life style and poor dietary habits. Ferulic acid is known to have anti-cancer activity, anti-oxidant activity and also known to be less toxic to normal cells under high doses. The purpose of this research is to develop an oral dietary intervention by grafting ferulic acid to fructo oligosaccharide and there by self-assembling them in to microparticles for targeted delivery to colon. The microparticle is characterized by using Solid state NMR and FTIR. Their morphological features were studied using SEM, XRD and particle size analyzer. The stability of the microparticle under simulated gastric and intestinal digestion were investigated. The physico-chemical characteristics of the microparticle was investigated by thermogravimetric analysis and by differential scanning calorimetry. Finally the antioxidant activity and anti-cancer activity of the microparticles were investigated in-vitro.

Co-Delivery of Paclitaxel and Doxorubicin by pH-Responsive Prodrug Micelles for Cancer Therapy

Background

It is of great significance to develop intelligent co-delivery systems for cancer chemotherapy with improved therapeutic efficacy and few side-effects.

Materials and Methods

Here, we reported a co-delivery system based on pH-sensitive polyprodrug micelles for simultaneous delivery of doxorubicin (DOX) and paclitaxel (PTX) as a combination chemotherapy with pH-triggered drug release profiles. The physicochemical properties, drug release profiles and mechanism, and cytotoxicity of PTX/DOX-PMs have been thoroughly investigated.

Results and Discussion

The pH-sensitive polyprodrug was used as nanocarrier, and PTX was encapsulated into the micelles with high drug-loading content (25.6%). The critical micelle concentration (CMC) was about 3.16 mg/L, indicating the system could form the micelles at low concentration. The particle size of PTX/DOX-PMs was 110.5 nm, and increased to approximately 140 nm after incubation for 5 days which showed that the PTX/DOX-PMs had high serum stability. With decrease in pH value, the particle size first increased, and thenwas no longer detectable. Similar change trend was observed for CMC values. The zetapotential increased sharply with decrease in pH. These results demonstrated the pHsensitivity of PTX/DOX-PMs. In vitro drug release experiments and study on release mechanism showed that the drug release rate and accumulative release for PTX and DOX were dependent on the pH, showing the pH-triggered drug release profiles. Cytotoxicity assay displayed that the block copolymer showed negligible cytotoxicity, while the PTX/DOX-PMs possessed high cytotoxic effect against several tumor cell lines compared with free drugs and control.

Conclusion

All the results demonstrated that the co-delivery system based on pH-sensitive polyprodrug could be a potent nanomedicine for combination cancer chemotherapy. In addition, construction based on polyprodrug and chemical drug could be a useful method to prepare multifunctional nanomedicine.

Reduction-sensitive poly(ethylene glycol)-polypeptide conjugate micelles for highly efficient intracellular delivery and enhanced antitumor efficacy of hydroxycamptothecin

The non-specific biodistribution of traditional chemotherapeutic drugs against tumors is the key factor that causes systemic toxicity and hinders their clinical application. In this study, a reduction-sensitive polymer conjugate micelle was manufactured to achieve tumor-specific targeting, reduce toxic side-effects and improve anti-tumor activity of a natural anti-cancer drug, hydroxycamptothecin (HCPT). Therefore, HCPT was conjugated with methoxy-poly(ethylene glycol)-poly(β-benzyl-L-aspartate) (mPEG-PBLA) by a disulfide bond or succinate bond for the first time to obtain the mPEG-PBLA-SS-HCPT (PPSH) and mPEG-PBLA-CC-HCPT (PPCH) that would form micelles after high-speed agitation and dialysis. The PPSH micelles showed an average particle size of 126.3 nm, a low polydispersity index of 0.209, and a negative surface charge of -21.1 mV zeta potential. Transmission electron microscopy showed the PPSH micelles to have spherical morphology. PPSH had a low critical micelle concentration of 1.29 μg ml^-1 with high dilution stability, storage stability and reproducibility. Moreover, the particle size of the PPSH micelles had no significant change after incubation with rat plasma for 72 h, probably resulting in high long circulation in the blood. The PPSH micelles showed significant reduction sensitivity to glutathione. Their sizes increased by 403.2 nm after 24 h post-incubation, and 87.6% drug release was achieved 48 h post-incubation with 40 mM glutathione solutions. The PPSH micelles showed stronger inhibition of HepG2 cells in vitro and growth of H-22 tumor in vivo than the PPCH and HCPT solutions after intravenous injection. The accumulation of PPSH micelles in the tumor tissue contributed to the high anti-tumor effect with little side-effect on the normal tissues. The reduction-sensitive PPSH micelles were a promising carrier of HCPT and other poorly soluble anti-cancer drugs.

Polymeric Nanocarriers of Drug Delivery Systems in Cancer Therapy

Conventional chemotherapy is the most common therapeutic method for treating cancer by the application of small toxic molecules thatinteract with DNA and causecell death. Unfortunately, these chemotherapeutic agents are non-selective and can damage both cancer and healthy tissues,producing diverse side effects, andthey can have a short circulation half-life and limited targeting. Many synthetic polymers have found application as nanocarriers of intelligent drug delivery systems (DDSs). Their unique physicochemical properties allow them to carry drugs with high efficiency,specificallytarget cancer tissue and control drug release. In recent years, considerable efforts have been made to design smart nanoplatforms, including amphiphilic block copolymers, polymer-drug conjugates and in particular pH- and redox-stimuli-responsive nanoparticles (NPs). This review is focused on a new generation of polymer-based DDSs with specific chemical functionalities that improve their hydrophilicity, drug loading and cellular interactions.Recentlydesigned multifunctional DDSs used in cancer therapy are highlighted in this review.

Co-delivery system of chemotherapy drugs and active ingredients from natural plants: a brief overview of preclinical research for cancer treatment

Introduction: Many active ingredients from natural plants (AINPs) have been revealed to possess remarkable anticancer properties. Combination chemotherapy of chemo-drugs and AINPs has also proven to be more advantageous than individual chemo-drug treatment with respect to enhancing efficiency, alleviating toxicity, and controlling the development of multidrug resistance (MDR). Co-delivery is considered a promising method to effectively achieve and manage combination chemotherapy of chemo-drugs and AINPs, and various distinctive and functional co-delivery systems have been designed for these purposes to date.Areas covered: This review focuses on recent preclinical investigations of co-delivery systems for chemo-drugs and AINPs as new cancer treatment modalities. We particularly emphasize the apparent treatment advantages of these approaches, including augmenting efficiency, reducing toxicity, and controlling MDR.Expert opinion: There has already been notable progress in the application of combination chemotherapy with co-delivery systems loaded with chemo-drugs and AINPs based on results with cellular and animal models. The main challenge is to translate these successes into new anticancer compound preparations and promote their clinical application in practice. Nevertheless, continuous efforts with new designs of co-delivery systems remain essential, providing a foundation for future clinical research and development of new anticancer drugs.

Temperature sensitive hydrogel for preoperative treatment of renal carcinoma

Surgical resection has been suggested as an effective and first-line treatment of renal cell carcinoma (RCC). However, operation is quite difficult for the patients with stage of middle-late or hypervascularized tumors. Transarterial chemoembolization (TACE) plays an important role in decreasing the size of tumors before surgery. In this work, we prepared an injectable drug-delivery system of doxorubicin-loaded temperature sensitive hydrogel for transarterial chemoembolization in RCC. The sol-gel transition behavior and rheologic analysis showed that the doxorubicin-loaded temperature sensitive hydrogel had good temperature sensitivity. Then, The X-ray experiment of hydrogel showed excellent visibility under the digital subtraction angiography and computed tomography scans in vitro and in vivo. Moreover, the studies of embolization in beagle's right kidney showed good properties in embolizing of renal arteries. In TACE therapy studies of rabbit VX₂ renal tumors, angiography, computed tomography and histopathological analysis verified that TACE therapy of doxorubicin-loaded temperature sensitive hydrogel had excellent embolic efficiency as a result of repressing the tumor growth. This hydrogel could provide valuable option in the treatment of renal cell carcinoma before surgery.

Ditelluride-Bridged PEG-PCL Copolymer as Folic Acid-Targeted and Redox-Responsive Nanoparticles for Enhanced Cancer Therapy

The development of the nanosized delivery systems with targeting navigation and efficient cargo release for cancer therapy has attracted great attention in recent years. Herein, a folic acid (FA) modified PEGylated polycaprolactone containing ditelluride linkage was synthesized through a facile coupling reaction. The hydrophobic doxorubicin (DOX) can be encapsulated into the polymeric micelles, and such nanoparticles (F-TeNPDOX) exhibited redox-responsive drug release under abundant glutathione (GSH) condition due to the degradation of ditelluride bonds. In addition, flow cytometric analyses showed that the FA ligands on F-TeNPDOX could facilitate their cellular uptake in 4T1 breast cancer cells. Therefore, F-TeNPDOX led to the promoted drug accumulation and enhanced growth inhibition on 4T1 tumor in vivo. The obtained results suggest F-TeNPDOX excellent potential as nanocarriers for anticancer drug delivery.

Non-small cell lung cancer combination therapy: Hyaluronic acid modified, epidermal growth factor receptor targeted, pH sensitive lipid-polymer hybrid nanoparticles for the delivery of erlotinib plus bevacizumab

Non-small cell lung cancer (NSCLC) is the leading cause of cancer-related mortality in China. This study aimed to develop a hyaluronic acid (HA) decorated, pH sensitive lipid-polymer hybrid nanoparticles (LPH NPs) to co-deliver erlotinib (ERL) and bevacizumab (BEV) (HA-ERL/BEV-LPH NPs) for targeting and suppressing NSCLC. HA contained pH sensitive nano-materials were synthesized by acylation reaction. HA-ERL/BEV-LPH NPs were prepared using a sonication method. To explore the efficiency of the system, we evaluated the physicochemical parameters and performed a release study, a cellular uptake assay, a cytotoxicity evaluation, and several in vivo anti-tumor studies in comparison with free drugs and single drug systems. All LPH NPs samples have particle sizes of about 100-120 nm, polydispersity index values range from 0.12 to 0.15, and negative zeta potentials. HA-ERL/BEV-LPH NPs contained pH sensitive adipic acid dihydrazide (ADH) showed fast drug release at pH 5.5 than pH 7.4. After 21 days, the tumor volume of the HA-ERL/BEV-LPH NPs group (229.2 ± 13.1 mm³) was significantly smaller than 0.9 % NaCl control group (1126.3 ± 39.4 mm³), with a tumor inhibition rate of 79.7 ± 3.2 %. The maximum plasma ERL concentrations, half life period, and area under the curve of HA-ERL/BEV-LPH NPs were 21.6 μg/mL, 7.57 h, and 290.3 mg/L·h). With the highest tumor tissue accumulation concentration (25.3 μg/mL) and low system toxicity, HA-ERL/BEV-LPH NPs. HA-ERL/BEV-LPH NPs could be used as a promising system for the combination therapy of NSCLC.

Novel pH-triggered biocompatible polymeric micelles based on heparin-α-tocopherol conjugate for intracellular delivery of docetaxel in breast cancer

In this study, pH-triggered polymeric micelle comprising α-tocopherol (TOC) and heparin (HEP) was developed and loaded with docetaxel (DTX). The amphiphilic copolymer was synthesized by grafting TOC onto HEP backbone by a pH-cleavable bond. DTX-loaded micelles were characterized in terms of critical micelle concentration (CMC), particle size, zeta potential, entrapment efficiency (EE), pH-responsive behavior, and drug release. In vitro cytotoxicity of the micelles against breast cancer cells was investigated by MTT assay. The cellular uptake of coumarin-loaded micelles was also evaluated. Furthermore, the pharmacokinetics of DTX-loaded micelles was evaluated and compared with that of Taxotere^®.HEP-CA-TOC copolymers showed low CMC values and high EE. At pH 7.4, the micelles remained stable in size and shape, whereas considerable changes in particle size and morphology were observed at pH 5.5. DTX-loaded micelles showed pH-dependent drug release profiles. Coumarin-loaded micelles showed higher cellular uptake than free coumarin. Therefore, the DTX-loaded micelles showed more toxicity against breast cancer cells than free DTX. A significant increase in T_1/2 β, AUC_0-∞ and MRT was observed in DTX-loaded micelle treated group as compared to the group treated with Taxotere^®.The results suggest that the pH-sensitive HEP-modified micelles could be promising for enhanced intracellular drug delivery of DTX for cancer treatment.

A glance over doxorubicin based-nanotherapeutics: From proof-of-concept studies to solutions in the market

Cancer is one of the leading causes of death worldwide and, as such, efforts are being done to find new chemotherapeutic drugs or, alternatively, novel approaches for the delivery of old ones. In this scope, when used as vehicles for drugs, nanomaterials may potentially maximize the efficacy of the treatment and reduce its side effects, for example by a change in drug's pharmacokinetics, cell targeting and/or specific stimuli-responsiveness. This is the case of doxorubicin (DOX) that presents a broad spectrum of activity and is one of the most widely used chemotherapeutic drugs as first-line treatment. Indeed, DOX is a very interesting example of a drug for which several nanosized delivery systems have been developed over the years. While it is true that some of these systems are already in the market, it is also true that research on this subject remains very active and that there is a continuing search for new solutions. In this sense, this review takes the example of doxorubicin, not so much with the focus on the drug itself, but rather as a case study around which very diverse and imaginative nanotechnology approaches have emerged.

Stimuli-responsive polymeric prodrug-based nanomedicine delivering nifuroxazide and doxorubicin against primary breast cancer and pulmonary metastasis

Functionalized drug delivery systems against malignant lung metastasis of breast cancer have been extensively studied, while metastasis remains a challenging issue. We propose a new strategy to achieve eradication of primary breast cancer cells and inhibition of pulmonary metastasis. A cathepsin B/pH dual-sensitive block copolymer with a molecular weight of 92 kDa was synthesized to conjugate with doxorubicin (DOX). The copolymer-DOX was further loaded with nifuroxazide (NFX) to self-assemble co-prodrug-loaded micelles (CLM). CLM displayed a drug release pattern in response to pH/enzyme dual stimuli and was enzymatically biodegradable. CLM was demonstrated to reduce viability and inhibit migration and invasion of 4T1 murine breast cancer cells in vitro. After i.v. injection of CLM, its nanoscale size and stimuli-responsiveness facilitated delivery of drugs to the tumor site in mice. Enhanced anti-tumor efficacy and great anti-metastatic effects were found in both orthotropic and lung metastasis 4T1 breast cancer mice models. Meanwhile, histological immunofluorescence and immunohistochemical analyses revealed a high level of apoptosis, suppressed expression of matrix metalloproteinases and reduction in MDSCs infiltration, and all these contributed to inhibit pulmonary metastasis. CLM may be explored as a potential nanomedicine against breast cancer metastasis.

Development of Long-Circulating and Fusogenic Liposomes Co-encapsulating Paclitaxel and Doxorubicin in Synergistic Ratio for the Treatment of Breast Cancer

Background:

The co-encapsulation of paclitaxel (PTX) and doxorubicin (DXR) in liposomes has the potential to offer pharmacokinetic and pharmacodynamic advantages, providing delivery of both drugs to the tumor at the ratio required for synergism.

Objective:

To prepare and characterize long-circulating and fusogenic liposomes co-encapsulating PTX and DXR in the 1:10 molar ratio (LCFL-PTX/DXR).

Methods:

LCFL-PTX/DXR was prepared by the lipid film formation method. The release of PTX and DXR from liposomes was performed using a dialysis method. Studies of cytotoxicity, synergism, and cellular uptake were also carried out.

Results:

The encapsulation percentage of PTX and DXR was 74.1 ± 1.8 % and 89.6 ± 12.3%, respectively, and the mean diameter of the liposomes was 244.4 ± 28.1 nm. The vesicles remained stable for 30 days after their preparation. The drugs were simultaneously released from vesicles during 36 hours, maintaining the drugs combination in the previously established ratio. Cytotoxicity studies using 4T1 breast cancer cells showed lower inhibitory concentration 50% (IC50) value for LCFL-PTX/DXR treatment (0.27 ± 0.11 µm) compared to the values of free drugs treatment. In addition, the combination index (CI) assessed for treatment with LCFL-PTX/DXR was equal to 0.11 ± 0.04, showing strong synergism between the drugs. Cell uptake studies have confirmed that the molar ratio between PTX and DXR is maintained when the drugs are administered in liposomes.

Conclusion:

It was possible to obtain LCFL-PTX/DXR suitable for intravenous administration, capable of releasing the drugs in a fixed synergistic molar ratio in the tumor region.

Improving breast cancer therapy using doxorubicin loaded solid lipid nanoparticles: Synthesis of a novel arginine-glycine-aspartic tripeptide conjugated, pH sensitive lipid and evaluation of the nanomedicine in vitro and in vivo

Breast cancer is the leading cause of cancer mortality in women worldwide. To overcome the toxic side effects and multidrug resistance (MDR) during doxorubicin (DOX) chemotherapy, an arginine-glycine-aspartic (RGD) tripeptide modified, pH-sensitive solid lipid nanoparticles (SLNs) is employed in this study. In this study, a RGD conjugated, pH sensitive lipid was synthesized using glycerin monostearate (GMS) and adipic acid dihydrazide (HZ) as lipid materials and named RGD-HZ-GMS. RGD-HZ-GMS was applied to encapsulate DOX to construct a RGD modified, DOX loaded SLNs (RGD-DOX-SLNs). To evaluate the anticancer effect of RGD-DOX-SLNs, breast cancer cell line (MCF-7 cells) and DOX resistant cell line (MCF-7/ADR cells) were used. in vivo tumor suspension and toxicity effects were evaluated on mice bearing MCF-7/ADR cells breast cancer model. RGD-DOX-SLNs had a uniformly spherical shape. The mean particle size and zeta potential of the RGD-DOX-SLNs was 96.3 nm and 35.6 mV, respectively. RGD-DOX-SLNs showed 5.58 fold higher area under the plasma concentration - time curve (AUC) compared with DOX solution. Terminal half life (T_1/2) and peak concentration (C_max) of RGD-DOX-SLNs was 10.85 h and 39.12 ± 2.71 L/kg/h. in vitro and in vivo antitumor results indicate that RGD-DOX-SLNs might be a promising novel lipid carrier which could improve breast cancer therapy.

ROS-responsive targeting micelles for optical imaging-guided chemo-phototherapy of cancer

The combination of chemotherapy and phototherapy gives rise to a boom in cancer therapy methodology. An all-in-one nanoplatform is of particular interest for increased safety and efficacy geared toward personalized precision medicine. However, low drug loading efficiency, random dispersion and distribution without visualization are widespread concerns. Here, a reactive oxygen species (ROS) responsive drug delivery system for imaging-guided chemo-phototherapy was developed. Polymeric micelles were designed and synthesized using PTX (drug) and Cypate (fluorescence and photosensitizer) as hydrophobic segments and PEG as hydrophilic ones encapsulating PTX. Furthermore, folic acid, as a targeting moiety, was conjugated to PEG for directed drug delivery. We evaluated the ROS-responsive drug release profiles and chemo-phototherapy application in an anticancer therapy. The results suggest these biocompatible amphiphilic polymer conjugates would be promising for applications in imaging-guided chemo-phototherapy.

Polymeric Co-Delivery Systems in Cancer Treatment: An Overview on Component Drugs' Dosage Ratio Effect

Multiple factors are involved in the development of cancers and their effects on survival rate. Many are related to chemo-resistance of tumor cells. Thus, treatment with a single therapeutic agent is often inadequate for successful cancer therapy. Ideally, combination therapy inhibits tumor growth through multiple pathways by enhancing the performance of each individual therapy, often resulting in a synergistic effect. Polymeric nanoparticles prepared from block co-polymers have been a popular platform for co-delivery of combinations of drugs associated with the multiple functional compartments within such nanoparticles. Various polymeric nanoparticles have been applied to achieve enhanced therapeutic efficacy in cancer therapy. However, reported drug ratios used in such systems often vary widely. Thus, the same combination of drugs may result in very different therapeutic outcomes. In this review, we investigated polymeric co-delivery systems used in cancer treatment and the drug combinations used in these systems for synergistic anti-cancer effect. Development of polymeric co-delivery systems for a maximized therapeutic effect requires a deeper understanding of the optimal ratio among therapeutic agents and the natural heterogenicity of tumors.

Lung cancer therapy using doxorubicin and curcumin combination: Targeted prodrug based, pH sensitive nanomedicine

Lung cancer is the leading cause of cancer death worldwide. To overcome the toxic side effects and multidrug resistance (MDR) during doxorubicin (DOX) chemotherapy, a urokinase plasminogen activator receptor (uPAR) targeting U11 peptide decorated, pH-sensitive, dual drugs co-encapsulated nanoparticles (NPs) system is employed in this study. A U11 peptide conjugated, pH-sensitive DOX prodrug (U11-DOX) was synthesized and used as materials to produce NPs. A curcumin (CUR) and U11-DOX co-encapsulated NPs system (U11-DOX/CUR NPs) was constructed to treat lung cancer. After the characterization of biophysical properties of this NPs system, synergistic chemotherapeutic efficacy was evaluated in both cultured cancer cells and tumor-bearing animal model. U11-DOX/CUR NPs had a uniformly spherical shape with a core-shell structure. The mean particle size and zeta potential of the U11-DOX/CUR NPs was 121.3 nm and -33.5 mV, with a DOX and CUR EE of 81.7 and 90.5%, respectively. The DOX release from U11-DOX/CUR NPs was 83.5, 55.2, and 32.8% correspondence to the pH of 5.0, 6.0 and 7.4. Cellular uptake efficiency of U11-DOX/CUR NPs was significantly higher than non U11 peptide decorated DOX/CUR NPs. U11-DOX/CUR NPs displayed a pronounced synergy effects in vitro and an obvious tumor tissue accumulation efficiency in vivo. In vivo antitumor experiment showed that U11-DOX/CUR NPs could inhibit the tumor growth to a level of 85%.In vitro and in vivo studies demonstrated that U11-DOX/CUR NPs is a sustained released, pH responsive, synergistic antitumor system. This study suggests that the U11-DOX/CUR NPs have promising potential for combination treatment of lung cancer.

Modern Assay Techniques for Cancer Drugs: Electroanalytical and Liquid Chromatography Methods

In the past decades, patients who have chemotherapy treatment have considerably increased number. At this point, the development of rapid precise, and reliable methods are very important to analyze cancer drugs from their dosage forms, animals or human biological samples. Among all the analytical methods, electrochemical methods hold an important position with their unique properties such as specificity in the biological recognition process, fast response, and their reliability and do not need a pretreatment process. Chromatographic methods are also used in a wide range of analytical applications for the analyses of anticancer drugs. The power of chromatography comes from its ability to separate a mixture of analytes and determination of their concentrations. Chromatographic techniques can mainly be divided into gas, liquid, and supercritical fluid chromatography. In the frame of this information, this review is aimed to provide basic principles of electroanalytical and high-performance liquid chromatography methods for the analysis of cancer drugs. In addition, some selected applications for electrochemistry-related techniques and high-performance liquid chromatography, for the determination of anti-cancer pharmaceuticals published in the last five years are also discussed.

Eph A10-modified pH-sensitive liposomes loaded with novel triphenylphosphine-docetaxel conjugate possess hierarchical targetability and sufficient antitumor effect both in vitro and in vivo

Mitochondrial-targeting therapy was considered to be a promising approach for the efficient treatment of cancer while positive charge induced nonspecific cytotoxicity severely limits its application. To overcome this drawback, a novel mitochondria targeted conjugate triphenylphosphine-docetaxel (TD) has been synthesized successfully and incorporated it into liposomes (EPSLP/TD), which possessed excellent pH-sensitive characteristic, EphA 10 mediated active targetability as well as mitochondria-targeting capability. EPSLP/TD was characterized to have a small particle size, high-encapsulation efficiency and excellent pH-sensitive characteristic. Compared with DTX-loaded liposomes (EPSLP/DTX), EPSLP/TD possessed higher cytotoxicity against MCF-7 cell line. Mitochondrial-targeting assay demonstrated mitochondria-targeting moiety triphenylphosphine (TPP) could efficiently deliver DTX to mitochondria. Western immunoblotting assay indicated that EPSLP/TD could efficiently deliver antitumor drug to mitochondria and induce cell apoptosis via mitochondria-mediated apoptosis pathway. In vivo antitumor study demonstrated EPSLP/TD owed excellent in vivo antitumor activity. Histological assay demonstrated EPSLP/TD showed strongly apoptosis inducing effect, anti-proliferation effect and anti-angiogenesis effect. This work investigated the potential of hierarchical targeting pH-sensitive liposomes is a suitable carrier to activate mitochondria-mediated apoptosis pathway for cancer therapy.