Enhanced in vivo antitumor efficacy of dual-functional peptide-modified docetaxel nanoparticles through tumor targeting and Hsp90 inhibition

Autophagy and Biomaterials: A Brief Overview of the Impact of Autophagy in Biomaterial Applications

Macroautophagy (hereafter autophagy), a tightly regulated physiological process that obliterates dysfunctional and damaged organelles and proteins, has a crucial role when biomaterials are applied for various purposes, including diagnosis, treatment, tissue engineering, and targeted drug delivery. The unparalleled physiochemical properties of nanomaterials make them a key component of medical strategies in different areas, such as osteogenesis, angiogenesis, neurodegenerative disease treatment, and cancer therapy. The application of implants and their modulatory effects on autophagy have been known in recent years. However, more studies are necessary to clarify the interactions and all the involved mechanisms. The advantages and disadvantages of nanomaterial-mediated autophagy need serious attention in both the biological and bioengineering fields. In this mini-review, the role of autophagy after biomaterial exploitation and the possible related mechanisms are explored.

The interactions of docetaxel with tumor microenvironment

There are several interactions within the tumor microenvironment (TME) that affect the response of cancer cells to therapy. There are also a large number of cells and secretions in TME that increase resistance to therapy. Following the release of immunosuppressive, pro-angiogenic, and metastatic molecules by certain cells such as tumor-associated macrophages (TAMs), cancer-associated fibroblasts (CAFs), and cancer cells, immune evasion, angiogenesis, and metastasis may be induced. However, natural killer (NK) cells and cytotoxic CD8 + T lymphocytes (CTLs) can responsively release anticancer molecules. In addition, anticancer drugs can modulate these cells and their interactions in favor of either cancer resistance or therapy. Docetaxel belongs to taxanes, a class of anti-tumor drugs, which acts through the polymerization of tubulin and the induction of cell cycle arrest. Also, it has been revealed that taxanes including docetaxel affect cancer cells and the other cells within TME through some other mechanisms such as modulation of immune system responses, angiogenesis, and metastasis. In this paper, we explain the basic mechanisms of docetaxel interactions with malignant cells. Besides, we review the diverse effects of docetaxel on TME and cancer cells in consequence. Lastly, the modulatory effects of docetaxel alone or in conjunction with other anticancer agents on anti-tumor immunity, cancer cell resistance, angiogenesis, and metastasis will be discussed.

Learn from antibody–drug conjugates: consideration in the future construction of peptide-drug conjugates for cancer therapy

Cancer is one of the leading causes of death worldwide due to high heterogeneity. Although chemotherapy remains the mainstay of cancer therapy, non-selective toxicity and drug resistance of mono-chemotherapy incur broad criticisms. Subsequently, various combination strategies have been developed to improve clinical efficacy, also known as cocktail therapy. However, conventional “cocktail administration” is just passable, due to the potential toxicities to normal tissues and unsatisfactory synergistic effects, especially for the combined drugs with different pharmacokinetic properties. The drug conjugates through coupling the conventional chemotherapeutics to a carrier (such as antibody and peptide) provide an alternative strategy to improve therapeutic efficacy and simultaneously reduce the unspecific toxicities, by virtue of the advantages of highly specific targeting ability and potent killing effect. Although 14 antibody–drug conjugates (ADCs) have been approved worldwide and more are being investigated in clinical trials so far, several limitations have been disclosed during clinical application. Compared with ADCs, peptide-drug conjugates (PDCs) possess several advantages, including easy industrial synthesis, low cost, high tissue penetration and fast clearance. So far, only a handful of PDCs have been approved, highlighting tremendous development potential. Herein, we discuss the progress and pitfalls in the development of ADCs and underline what can learn from ADCs for the better construction of PDCs in the future.

DTX-P7, a peptide-drug conjugate, is highly effective for non-small cell lung cancer

Despite tremendous success of molecular targeted therapy together with immunotherapy, only a small subset of patients can benefit from them. Chemotherapy remains the mainstay treatment for most of tumors including non-small cell lung cancer (NSCLC); however, non-selective adverse effects on healthy tissues and secondary resistance are the main obstacles. Meanwhile, the quiescent or dormant cancer stem-like cells (CSLCs) are resistant to antimitotic chemoradiotherapy. Complete remission can only be realized when both proliferative cancer cells and quiescent cancer stem cells are targeted. In the present research, we constructed a cooperatively combating conjugate (DTX-P7) composed of docetaxel (DTX) and a heptapeptide (P7), which specifically binds to cell surface Hsp90, and assessed the anti-tumor effects of DTX-P7 on non-small cell lung cancer. DTX-P7 preferentially suppressed tumor growth compared with DTX in vivo with a favorable distribution to tumor tissues and long circulation half-life. Furthermore, we revealed a distinctive mechanism whereby DTX-P7 induced unfolded protein response and eventually promoted apoptosis. More importantly, we found that DTX-P7 promoted cell cycle reentry of slow-proliferating CSLCs and subsequently killed them, exhibiting a "proliferate to kill" pattern. Collecitvely, by force of active targeting delivery of DTX via membrane-bound Hsp90, DTX-P7 induces unfolded protein response and subsequent apoptosis by degrading Hsp90, meanwhile awakens and kills the dormant cancer stem cells. Thus, DTX-P7 deserves further development as a promising anticancer therapeutic for treatment of various membrane-harboring Hsp90 cancer types.

Targeted Drug Delivery for the Treatment of Blood Cancers

Blood cancers are a type of liquid tumor which means cancer is present in the body fluid. Multiple myeloma, leukemia, and lymphoma are the three common types of blood cancers. Chemotherapy is the major therapy of blood cancers by systemic administration of anticancer agents into the blood. However, a high incidence of relapse often happens, due to the low efficiency of the anticancer agents that accumulate in the tumor site, and therefore lead to a low survival rate of patients. This indicates an urgent need for a targeted drug delivery system to improve the safety and efficacy of therapeutics for blood cancers. In this review, we describe the current targeting strategies for blood cancers and recently investigated and approved drug delivery system formulations for blood cancers. In addition, we also discuss current challenges in the application of drug delivery systems for treating blood cancers.

Co-delivery of the autophagy inhibitor si-Beclin1 and the doxorubicin nano-delivery system for advanced prostate cancer treatment

Resistance to apoptosis is a key mechanism underlying how cancer cells evade tumor therapy. Autophagy can prevent anticancer drug-induced apoptosis and promote tumor resistance. The purpose of this study was to improve the sensitivity and efficacy of chemotherapeutic drugs through the inhibition of autophagy. Hydrophobic doxorubicin-hydrazone-caproyl-maleimide (DOX-EMCH) and autophagy-inhibiting si-Beclin1 were simultaneously delivered via the amphiphilic peptide micelle system (Co-PMs) using poly(L-arginine)-poly(L-histidine)-DOX-EMCH as the copolymer building unit. The constructed micelle system promoted the escape of si-Beclin1 from endosomes and the release of DOX into the nucleus. The Co-PMs exhibited 2.7-fold higher cytotoxicity and proapoptotic ability in PC3 cells than DOX treatment alone, demonstrating that si-Beclin1 could inhibit the autophagic activity of prostate cancer (PCa) cells by targeting the type III PI3K pathway and enhance the sensitivity of the cells to the chemotherapeutic drug DOX. In addition, the peptide micelles successfully passively targeted DOX and si-Beclin1 to the tumor tissue. Compared with DOX or si-Beclin1 treatment alone, the Co-PMs showed a 3.4-fold greater tumor inhibitory potential in vivo, indicative of a significant antiproliferative effect. Our results suggested that the Co-PMs developed in this study have the potential to combine autophagy inhibition and chemotherapy in cancer treatment, especially for PCa.

Tumor-targeted delivery of siRNA to silence Sox2 gene expression enhances therapeutic response in hepatocellular carcinoma

RNA interference (RNAi) is one of the most promising methods for the treatment of malignant tumors. However, developing an efficient biocompatible delivery vector for small interfering RNA (siRNA) remains a challenging issue. This study aimed to prepare a non-viral tumor-targeted carrier, named RGDfC-modified functionalized selenium nanoparticles (RGDfC-SeNPs). RGDfC-SeNPs were used to selectively deliver siSox2 to HepG2 liver cancer cells and tissues for the treatment of hepatocellular carcinoma (HCC). In the current study, RGDfC-SeNPs were successfully synthesized and characterized. It was shown that RGDfC-SeNPs could effectively load siSox2 to prepare an antitumor prodrug RGDfC-Se@siSox2. RGDfC-Se@siSox2 exhibited selective uptake in HepG2 liver cancer cells and LO2 normal liver cells, indicating RGDfC-SeNPs could effectively deliver siSox2 to HepG2 liver cancer cells. RGDfC-Se@siSox2 entered HepG2 cells via clathrin-mediated endocytosis by firstly encircling the cytoplasm and then releasing siSox2 in the lysosomes. RGDfC-Se@siSox2 could effectively silence Sox2 and inhibit the proliferation, migration and invasion of HepG2 cells. RGDfC-Se@siSox2 induced HepG2 cells apoptosis most likely via overproduction of reactive oxygen species and disruption of the mitochondrial membrane potentials. Most importantly, RGDfC-Se@siSox2 significantly inhibited the tumor growth in HepG2 tumor-bearing mice without obvious toxic side effects. These studies indicated that RGDfC-SeNPs may be an ideal gene carrier for delivering siSox2 to HepG2 cells and that RGDfC-Se@siSox2 may be a novel and highly specific gene-targeted prodrug therapy for HCC.

Nanomaterial-mediated autophagy: coexisting hazard and health benefits in biomedicine

BACKGROUND

Widespread biomedical applications of nanomaterials (NMs) bring about increased human exposure risk due to their unique physicochemical properties. Autophagy, which is of great importance for regulating the physiological or pathological activities of the body, has been reported to play a key role in NM-driven biological effects both in vivo and in vitro. The coexisting hazard and health benefits of NM-mediated autophagy in biomedicine are nonnegligible and require our particular concerns.

MAIN BODY

We collected research on the toxic effects related to NM-mediated autophagy both in vivo and in vitro. Generally, NMs can be delivered into animal models through different administration routes, or internalized by cells through different uptake pathways, exerting varying degrees of damage in tissues, organs, cells, and organelles, eventually being deposited in or excreted from the body. In addition, other biological effects of NMs, such as oxidative stress, inflammation, necroptosis, pyroptosis, and ferroptosis, have been associated with autophagy and cooperate to regulate body activities. We therefore highlight that NM-mediated autophagy serves as a double-edged sword, which could be utilized in the treatment of certain diseases related to autophagy dysfunction, such as cancer, neurodegenerative disease, and cardiovascular disease. Challenges and suggestions for further investigations of NM-mediated autophagy are proposed with the purpose to improve their biosafety evaluation and facilitate their wide application. Databases such as PubMed and Web of Science were utilized to search for relevant literature, which included all published, Epub ahead of print, in-process, and non-indexed citations.

CONCLUSION

In this review, we focus on the dual effect of NM-mediated autophagy in the biomedical field. It has become a trend to use the benefits of NM-mediated autophagy to treat clinical diseases such as cancer and neurodegenerative diseases. Understanding the regulatory mechanism of NM-mediated autophagy in biomedicine is also helpful for reducing the toxic effects of NMs as much as possible.

α3β1 Integrin-Targeting Polymersomal Docetaxel as an Advanced Nanotherapeutic for Nonsmall Cell Lung Cancer Treatment

Docetaxel (DTX) widely used for treating nonsmall cell lung cancer (NSCLC) patients is associated with dose-limiting side effects, especially neurotoxicity and myelosuppression. Here, we have developed cyclic cNGQGEQc peptide-directed polymersomal docetaxel (cNGQ-PS-DTX) as a targeted and multifunctional formulation for NSCLC. cNGQ-PS-DTX carrying 8.1 wt % DTX had a size of 93 nm, neutral surface charge, high stability, and glutathione-triggered DTX release behavior. Cytotoxicity studies demonstrated a clearly better antitumor activity of cNGQ-PS-DTX in α3β1 integrin overexpressing A549 human lung cancer cells than free DTX and nontargeted PS-DTX. cNGQ-PS-DTX showed a remarkably high tolerability (over 8 times better than free DTX) and slow elimination in mice. Importantly, cNGQ-PS-DTX exhibited greatly improved tumor accumulation and higher suppression of subcutaneous and orthotopic A549 xenografts as compared to PS-DTX and free DTX controls. α3β1 integrin-targeting polymersomal docetaxel emerges as an advanced nanotherapeutic for NSCLC treatment.

Meta-Analysis of Nanoparticle Delivery to Tumors Using a Physiologically Based Pharmacokinetic Modeling and Simulation Approach

Numerous studies have engineered nanoparticles with different physicochemical properties to enhance the delivery efficiency to solid tumors, yet the mean and median delivery efficiencies are only 1.48% and 0.70% of the injected dose (%ID), respectively, according to a study using a nonphysiologically based modeling approach based on published data from 2005 to 2015. In this study, we used physiologically based pharmacokinetic (PBPK) models to analyze 376 data sets covering a wide range of nanomedicines published from 2005 to 2018 and found mean and median delivery efficiencies at the last sampling time point of 2.23% and 0.76%ID, respectively. Also, the mean and median delivery efficiencies were 2.24% and 0.76%ID at 24 h and were decreased to 1.23% and 0.35%ID at 168 h, respectively, after intravenous administration. While these delivery efficiencies appear to be higher than previous findings, they are still quite low and represent a critical barrier in the clinical translation of nanomedicines. We explored the potential causes of this poor delivery efficiency using the more mechanistic PBPK perspective applied to a subset of gold nanoparticles and found that low delivery efficiency was associated with low distribution and permeability coefficients at the tumor site (P < 0.01). We also demonstrate how PBPK modeling and simulation can be used as an effective tool to investigate tumor delivery efficiency of nanomedicines.

Ginsenoside Rg3 regulates DNA damage in non-small cell lung cancer cells by activating VRK1/P53BP1 pathway

Lung cancer is the leading cause of cancer-related deaths. Ginsenoside Rg3 is the main ingredient of Ginseng which is used to treat non-small cell lung cancer (NSCLC). It has been found to enhance the efficiency of chemotherapy thereby reducing its side effects. Previous studies found that ginsenoside Rg3 can reduce the occurrence of NSCLC by inducing DNA damage. Yet, its anti-DNA damaging effects and mechanisms in tumor cells are still not fully understood. This study explored the effect of ginsenoside Rg3 on DNA repair and VRK1/P53BP1 signaling pathway. Ginsenoside Rg3 treatment significantly decreased the incidence and invasionin a mouse model of lung cancer induced by urethane. The results of cell survival assay and single cell gel electrophoresis showed that ginsenoside Rg3 protected lung adenocarcinoma cells from DNA damage as well as inhibited the proliferation of tumor cells. Ginsenoside Rg3 increased the mRNA and protein expression of VRK1 in NSCLC cells as measured by RT-qPCR and western blot, respectively. These findings suggests that ginsenoside Rg3 regulates VRK1 signaling. Immunofluorescence assays showed that P53BP1 and VRK1 protein level increased, and the VRK1 protein translocated between the nuclei and cytoplasm. Finally, this conclusion was confirmed by the reverse validation in VRK1-knockdown cells. Taken together, these results show that ginsenoside Rg3 upregulate VRK1 expression and P53BP1 foci formation in response to DNA damage thereby inhibiting the tumorigenesis and viability of cancer cells. These findings reveal the role of Rg3 in lung cancer and provides therapeutic targets for developing new drugs in the prevention and treatment of lung cancer.

Multifunctional Zn doped hollow mesoporous silica/polycaprolactone electrospun membranes with enhanced hair follicle regeneration and antibacterial activity for wound healing

Due to the complexity of the skin tissue structure, the regeneration of the entire skin, including skin appendages such as hair follicles, is a big challenge. In addition, skin trauma is often accompanied by bacterial infections that delay the wound healing. Therefore, developing wound dressings, which promote hair follicle regeneration and inhibit bacterial infection in the wound healing process, is of great clinical significance. In this study, Zn doped hollow mesoporous silica nanospheres (HMZS) were synthesized by a sol-gel method and a novel wound healing dressing was prepared by incorporation of drug ciprofloxacin hydrochloride (CiH)-loaded Zn containing mesoporous silica nanospheres (CiH-HMZS) into polycaprolactone (PCL) electrospun fibers. The CiH-HMZS/P nano-composite electrospun fibers exhibit the ability to promote angiogenesis and skin regeneration by releasing Si ions, and the activity to enhance hair follicle regeneration and inhibit bacterial growth by releasing zinc ions and achieve the synergistic antibacterial effect with both Zn ions and CiH in low concentrations. Thus, the CiH-HMZS/P nano-composite membrane is a promising multi-functional wound healing material for inhibiting bacterial growth in infected wounds and enhancing skin wound healing including hair follicle regeneration.

Pro-apoptotic peptides-based cancer therapies: challenges and strategies to enhance therapeutic efficacy

Cancer is a leading cause of death worldwide. Despite many advances in the field of cancer therapy, an effective cure is yet to be found. As a more potent alternative for the conventional small molecule anti-cancer drugs, pro-apoptotic peptides have emerged as a new class of anticancer agents. By interaction with certain members in the apoptotic pathways, they could effectively kill tumor cells. However, there remain bottleneck challenges for clinical application of these pro-apoptotic peptides in cancer therapy. In this review, we will overview the developed pro-apoptotic peptides and outline the widely adopted molecular-based and nanoparticle-based strategies to enhance their anti-tumor effects.

Seek and destroy: improving PK/PD profiles of anticancer agents with nanoparticles

INTRODUCTION

The Pharmacokinetics/pharmacodynamics (PK/PD) relationships with cytotoxics are usually based on a steepening concentration-effect relationship; the greater the drug amount, the greater the effect. The Maximum Tolerated Dose paradigm, finding the balance between efficacy, while keeping toxicities at their manageable level, has been the rule of thumb for the last 50-years. Developing nanodrugs is an appealing strategy to help broaden this therapeutic window. The fact that efficacy and toxicity with cytotoxics are intricately linked is primarily due to the complete lack of specificity toward the tumor tissue during their distribution phase. Because nanoparticles are expected to better target tumor tissue while sparing healthy cells, accumulating large amounts of cytotoxics in tumors could be achieved in a safer way. Areas covered: This review aims at presenting how nanodrugs present unique features leading to reconsidering PK/PD relationships of anticancer agents. Expert commentary: The constant interplay between carrier PK, interactions with cancer cells, payload release, payload PK, target expression and target engagement, makes picturing the exact PK/PD relationships of nanodrugs particularly challenging. However, those improved PK/PD relationships now make the once contradictory higher efficacy and lower toxicities requirement an achievable goal in cancer patients.

Engineered nanomaterial applications in perinatal therapeutics

Engineered nanomaterials (ENM) are widely used in commercial, domestic, and more recently biomedical applications. While the majority of exposures to ENM are unintentional, biomedical platforms are being evaluated for use in individualized and/or tissue-targeted therapies. Treatments are often avoided during prenatal periods to reduce adverse effects on the developing fetus. The placenta is central to maternal-fetal medicine. Perturbation of placental functions can limit transfer of necessary nutrients, alter production of hormones needed during pregnancy, or allow undesired passage of xenobiotics to the developing fetus. The development of therapeutics to target specific maternal, placental, or fetal tissues would be especially important to reduce or circumvent toxicities. Therefore, this review will discuss the potential use of ENM in perinatal medicine, the applicable physiochemical properties of ENM in therapeutic use, and current methodologies of ENM testing in perinatal medicine, and identify maternal, fetal, and offspring concerns associated with ENM exposure during gestation. As potential nanoparticle-based therapies continue to develop, so does the need for thorough consideration and evaluation for use in perinatal medicine.

Lung cancer targeted therapy: Folate and transferrin dual targeted, glutathione responsive nanocarriers for the delivery of cisplatin

To achieve lung cancer targeted therapy, folic acid (FA) and transferrin (Tf) modified cisplatin (CDDP) loaded nanoparticles were applied for the in vitro and in vivo evaluation. The aim of this research was to develop FA modified SS bonds based prodrug of CDDP (namely FA-ss-CDDP) and Tf modified cystamine-oleic acid (Tf-ss-OA). Further, FA-ss-CDDP and Tf-ss-OA were used to prepare NPs, which could target the lung tumor cells through receptor-mediated pathways to increase the efficiency of CDDP. FA and Tf modified CDDP loaded NPs (FA/Tf-CDDP-NPs) were constructed. The physiochemical properties, in vitro drug release profiles, in vitro cytotoxicity, and in vivo biodistribution were investigated. The antitumor effect of self-assembed NPs was evaluated both in vitro and in vivo. FA/Tf-CDDP-NPs exhibited remarkably enhanced accumulation in tumor tissue and better tumor inhibition effect in vitro and in vivo. FA/Tf-CDDP-NPs displayed almost complete suppression of tumor growth with no obviously body weight change of the treated mice. The newly constructed NPs could successfully load drugs and showed better efficiency than free drug formula; and FA/TF could function as excellent targeting ligands to improve the cell targeting ability of the NPs. The resulting FA/Tf-CDDP-NPs offered a promising tumor therapy strategy for the treatment of lung cancer.

Ca-Doped mesoporous SiO2/dental resin composites with enhanced mechanical properties, bioactivity and antibacterial properties

MCS containing resin composites possess enhanced mechanical properties and antibacterial activity, and can smartly induce the deposition of apatite minerals.

Preparation and evaluation of RGD and TAT co-modified docetaxel-loaded liposome

The aim of this study is to develop a novel RGD and TAT co-modified docetaxel (DTX)-loaded liposome (LP) by the emulsification-solvent evaporation method. The prepared LPs were found to be in the size of 100 nm–110 nm. The transmission electron microscope photomicrographs were smooth, sub-spherical in shape, and aggregated to form small clusters. The DTX cumulative release from TAT and RGD co-modified LPs was significantly higher than that from other LPs due to decreased diffusion distance. Results of cell uptake showed that surface modification could indicate when cell internalization was changed and more drugs entered the cells successfully. Surprisingly, TAT and RGD co-modified DTX-LPs demonstrated a superior antiproliferative effect on A549 cells with a possible mechanism that suppressed the multidrug resistance phenomenon and exhibited a clear synergistic effect. In antitumor study, our results indicated that the form of TAT and RGD co-modified LPs had a better antitumor effect in vivo than the other formulations.

Homing in on an intracellular target for delivery of loaded nanoparticles functionalized with a histone deacetylase inhibitor

Functionalized nanoparticles (NPs) are usually used to enhance cellular penetration for targeted drug delivery that can improve efficacy and reduce side effects. However, it is difficult to exploit intracellular targets for similar delivery applications. Herein we describe the targeted delivery of functionalized NPs by homing in on an intracellular target, histone deacetylases (HDACs). Specifically, a modified poly-lactide-co-glycolideacid (FPLGA) was yielded by conjugation with an HDAC inhibitor. Subsequently, FPLGA was used to prepare functionalized FPLGA NPs. Compared to unmodified NPs, FPLGA NPs were more efficiently uptaken or retained by MCF-7 cells and showed longer retention time intracellular. In vivo fluorescence imaging also revealed that they had a higher accumulation and a slower elimination than unmodified NPs. FPLGA NPs loaded with paclitaxel exhibited superior anticancer efficacy compared with unmodified NPs. These results offer a promising approach for intracellular drug delivery through elevating the concentration of NPs.

Extended release delivery of erlotinib glutathione nanosponge for targeting lung cancer

Systemic and uncontrolled administration of erlotinib hydrochloride (ETB) is associated with severe toxicity. A novel targeted and extended release nanosponge (NS) was synthesized from glutathione (GHS) by a one-step reaction between β-cyclodextrin and pyromellitic dianhydride at room temperature for delivery of ETB in lung cancer. Characterization studies were performed using sophisticated instruments. In-vitro release study was performed in the presence of incremental concentrations of GHS which was analyzed using HPLC. Cell cytotoxicity study was evaluated on human lung cancer (A549) cell lines. In-vivo tumour inhibition and biodistribution of ETB-loaded GHS-NS (ETB-NS) were performed on BALB/c mice. NS obtained was spherical, size 212 ± 2.45 nm and high drug entrapment (92.34 ± 5.31%) (p < .001). In-vitro extended drug release (76.89 ± 0.1% release at 168 h), which was directly proportional to the concentration of GHS, demonstrated tumour targeting. There was enhanced in-vitro cytotoxicity and 97.5% inhibition in tumour growth on administering NS when compared to plain ETB (48% inhibition) indicating targeting of NS to the tumour site. Biodistribution study and in-vivo tumour growth inhibition study revealed drug release to the cancerous cell, thus preventing unnecessary drug exposure. ETB-NS exhibits extended drug release proportional to the external GSH concentration.

Transcription activator, hyaluronic acid and tocopheryl succinate multi-functionalized novel lipid carriers encapsulating etoposide for lymphoma therapy

Delivery of chemotherapeutic drugs using nanocarriers is emerging as a promising approach for the treatment of cancer. The aim of this research was to develop a dual targeted d-α-tocopheryl succinate (TOS) functionalized nanostructured lipid carriers (NLCs), using etoposide (ETP) as a model drug to prove their in vitro and in vivo anti-tumor effects. Novel ETP loaded NLCs were constructed (ETP-NLCs). Hyaluronic acid (HA) and cell-penetrating peptide transcription activator (TAT) was applied for the surface decoration of ETP NLCs (HATOS/TATTOS-ETP-NLCs). The antitumor efficiency of HATOS/TATTOS-ETP-NLCs was evaluated in tumor bearing animal models. HATOS/TATTOS-ETP-NLCs displayed significantly higher transfection efficiency and better antitumor ability than undecorated ETP-NLCs in lymphoma cells bearing mice model. The newly constructed NLCs could successfully load drug and gene; and TAT could function as excellent targeting ligands to improve the cell targeting ability of the gene loaded nanocarriers. The resulting dual ligands decorated vectors could be a promising targeted gene delivery system for the lymphoma treatment.

Surface engineering tumor cells with adjuvant-loaded particles for use as cancer vaccines

Cell surface engineering is an expanding field and whilst extensive research has been performed decorating cell surfaces with biomolecules, the engineering of cell surfaces with particles has been a largely unexploited area. This study reports on the assembly of cell-particle hybrids where irradiated tumor cells were surface engineered with adjuvant-loaded, biodegradable, biocompatible, polymeric particles, with the aim of generating a construct capable of functioning as a therapeutic cancer vaccine. Successfully assembled cell-particle hybrids presented here comprised either melanoma cells or prostate cancer cells stably adorned with Toll-like receptor-9 ligand-loaded particles using streptavidin-biotin cross-linking. Both cell-particle assemblies were tested in vivo for their potential as therapeutic cancer vaccines yielding promising therapeutic results for the prostate cancer model. The ramifications of results obtained for both tumor models are openly discussed.

Development of docetaxel nanocrystals surface modified with transferrin for tumor targeting

The purpose of this study was to develop the surface modification of docetaxel nanocrystals (DTX-NCs) with apo-Transferrin human (Tf) for improving the cellular uptake and cytotoxicity of DTX. DTX-NCs were prepared by a nanoprecipitation method, and the surface modified with Tf by an adsorption method (Tf-DTX-NCs). The morphology and particle size of DTX-NCs and Tf-DTX-NCs were characterized using a field emission scanning electron microscope and zetasizer. An in vitro drug release study was performed in phosphate-buffered saline containing 0.5% (w/v) Tween 80 for 24 hours. Cellular uptake was studied at 0.5, 1, and 2 hours. A cytotoxicity study was performed using the A549 (human lung cancer) cell line after 24-, 48-, and 72-hour treatments. The mean sizes were 295±97 and 398±102 nm for DTX-NCs and Tf-DTX-NCs, respectively. Tf-DTX-NCs and DTX-NCs exhibited rapid drug release, whereas DTX (pure) was slowly released. Tf-DTX-NCs showed higher cellular uptake than DTX-NCs in confocal microscopic and quantitative studies. Moreover, at DTX concentration of 100 µg/mL, Tf-DTX-NCs (82.6%±0.8%) showed higher cytotoxicity than DTX-NCs (77.4%±4.1%) and DTX (pure; 20.1%±4.6%) for 72-hour treatment. In conclusion, Tf-DTX-NCs significantly improved the cellular uptake and cytotoxicity of DTX in the A549 cell line.

Bacteriophages and phage-inspired nanocarriers for targeted delivery of therapeutic cargos

The main goal of drug delivery systems is to target therapeutic cargoes to desired cells and to ensure their efficient uptake. Recently a number of studies have focused on designing bio-inspired nanocarriers, such as bacteriophages, and synthetic carriers based on the bacteriophage structure. Bacteriophages are viruses that specifically recognize their bacterial hosts. They can replicate only inside their host cell and can act as natural gene carriers. Each type of phage has a particular shape, a different capacity for loading cargo, a specific production time, and their own mechanisms of supramolecular assembly, that have enabled them to act as tunable carriers. New phage-based technologies have led to the construction of different peptide libraries, and recognition abilities provided by novel targeting ligands. Phage hybridization with non-organic compounds introduces new properties to phages and could be a suitable strategy for construction of bio-inorganic carriers. In this review we try to cover the major phage species that have been used in drug and gene delivery systems, and the biological application of phages as novel targeting ligands and targeted therapeutics.