Tyroservatide-TPGS-paclitaxel liposomes: Tyroservatide as a targeting ligand for improving breast cancer treatment

Challenges and emerging strategies for next generation liposomal based drug delivery: An account of the breast cancer conundrum

The global cancer burden is witnessing an upsurge with breast cancer surpassing other cancers worldwide. Furthermore, an escalation in the breast cancer caseload is also expected in the coming years. The conventional therapeutic regimens practiced routinely are associated with many drawbacks to which nanotechnological interventions offer a great advantage. But how eminent could liposomes and their advantages be in superseding these existing therapeutic modalities? A solution is reflected in this review that draws attention to a decade-long journey embarked upon by researchers in this wake. This text is a comprehensive discussion of liposomes, the front runners of the drug delivery systems, and their active and passive targeting approaches for breast cancer management. Active targeting has been studied over the decade by many receptors overexpressed on the breast cancer cells and passive targeting with many drug combinations. The results converge on the fact that the actively targeted formulations exhibit a superior efficacy over their non-targeted counterparts and the all liposomal formulations are efficacious over the free drugs. This undoubtedly underlines the dominion of liposomal formulations over conventional chemotherapy. These investigations have led to the development of different liposomal formulations with active and passive targeting capacities that could be explored in depth. Acknowledging and getting a deeper insight into the liposomal evolution through time also unveiled many imperfections and unchartered territories that can be explored to deliver dexterous liposomal formulations against breast cancer and more in the clinical trial pipeline.

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.

Cutinase ACut2 from Blastobotrysraffinosifermentans for the Selective Desymmetrization of the Symmetric Diester Diethyl Adipate to the Monoester Monoethyl Adipate

Monoethyl adipate (MEA) is a highly valuable monoester for activating resistance mechanisms and improving protective effects in pathogen-attacked plants. The cutinase ACut2 from the non-conventional yeast Blastobotrys (Arxula) raffinosifermentans (adeninivorans) was used for its synthesis by the desymmetrization of dicarboxylic acid diester diethyl adipate (DEA). Up to 78% MEA with 19% diacid adipic acid (AA) as by-product could be synthesized by the unpurified ACut2 culture supernatant from the B. raffinosifermentans overexpression strain. By adjusting pH and enzyme concentration, the selectivity of the free ACut2 culture supernatant was increased, yielding 95% MEA with 5% AA. Selectivity of the carrier immobilized ACut2 culture supernatant was also improved by pH adjustment during immobilization, as well as carrier enzyme loading, ultimately yielding 93% MEA with an even lower AA concentration of 3-4%. Thus, optimizations enabled the selective hydrolysis of DEA into MEA with only a minor AA impurity. In the up-scaling, a maximum of 98% chemical and 87.8% isolated MEA yield were obtained by the adsorbed enzyme preparation with a space time yield of 2.6 g L-1 h-1. The high monoester yields establish the ACut2-catalyzed biosynthesis as an alternative to existing methods.

Micro- and nanoformulations of paclitaxel based on micelles, liposomes, cubosomes, and lipid nanoparticles: Recent advances and challenges

The diterpenoid molecule paclitaxel (PTX), extracted from the Western yew tree, Taxus brevifolia, is a promising anticancer drug specifically in clinical use for ovarian and breast cancers. However, its wider use is hampered by adverse effects and emerging resistance in cancer cells. Micelles, liposomes, cubosomes, and lipid nanoparticles (LNPs) have the potential to reduce or even remove complications associated with the use of PTX. Herein, we provide an overview of micro- and nanoformulations of PTX based on micelles, liposomes, cubosomes and LNPs to improve the therapeutic effects of this drug both in vitro and in vivo.

Increased antitumor efficacy of ginsenoside Rh2 via mixed micelles: in vivo and in vitro evaluation

The aim of this work is to apply Solutol^® HS15 and TPGS to prepare self-assembled micelles loading with ginsenoside Rh₂ to increase the solubility of ginsenoside Rh₂, hence, improving the antitumor efficacy. Ginsenoside Rh₂-mixed micelles (Rh₂-M) were prepared by thin film dispersion method. The optimal Rh₂-M was characterized by particle size, morphology, and drug encapsulation efficiency. The enhancement of in vivo anti-tumor efficacy of Rh₂-M was evaluated by nude mice bearing tumor model. The solubility of Rh₂ in self-assembled micelles was increased approximately 150-folds compared to free Rh₂. In vitro results demonstrated that the particle size of Rh₂-M is 74.72 ± 2.63 nm(PDI = 0.147 ± 0.15), and the morphology of Rh₂-M is spherical or spheroid, and the EE% and LE% are 95.27 ± 1.26% and 7.68 ± 1.34%, respectively. The results of in vitro cell uptake and in vivo imaging showed that Rh₂-M could not only increase the cell uptake of drugs, but also transport drug to tumor sites, prolonging the retention time. In vitro cytotoxicity and in vivo antitumor results showed that the anti-tumor effect of Rh₂ can be effectively improved by Rh₂-M. Therefore, Solutol^® HS15 and TPGS could be used to entrapping Rh₂ into micelles, enhancing solubility and antitumor efficacy.

A cocktail of betulinic acid, parthenolide, honokiol and ginsenoside Rh2 in liposome systems for lung cancer treatment

Aim: Lung cancer has a very high incidence rate, and thus, there is an urgent need for novel and effective therapies. Materials & methods: In this study, we proposed a potential treatment option by combining four natural products in liposome systems. Results: In vitro studies indicated that the combination of betulinic acid, parthenolide, honokiol and ginsenoside Rh2 exhibited a synergistic action. When these four natural products were loaded into liposome systems, we observed an increased effect. The relative action was also observed in vivo. The cisplatin group presented obvious kidney damage, whereas both cocktail therapy and cocktail liposome therapy were safer. Conclusion: Therefore, we propose cocktail liposome systems may provide a more efficient and safer treatment for lung cancer.

Indocyanine Green-Parthenolide Thermosensitive Liposome Combination Treatment for Triple-Negative Breast Cancer

Background

Certain patients with triple-negative breast cancer cannot tolerate the serious adverse effects of cytotoxic chemotherapy agents, which significantly affect the disease prognosis.

Purpose

Research into the combined use of photosensitizers and non-cytotoxic antineoplastic drugs for the safe treatment of triple-negative breast cancer is vital.

Methods

In this study, the photosensitizer indocyanine green and the natural drug parthenolide were co-loaded into thermosensitive liposomes. Under a near-infrared irradiation, indocyanine green reached excitation levels, releasing heat, and the liposome underwent a phase transition, releasing the drug were researched.

Results

Thus, indocyanine green and parthenolide exert synergistic antineoplastic effects. In the nude mice xenograft MDA-MB-231 tumor model, the tumor inhibition rate of indocyanine green-parthenolide thermosensitive liposomes was approximately 2.08-fold than that of paclitaxel and demonstrated a good initial safety evaluation.

Conclusion

Photosensitizers and non-cytotoxic antineoplastic agents in combination with nanoscale carriers should be further investigated for the treatment of tumors.

Combined administration of PTX and S-HM-3 in TPGS/Solutol micelle system for oncotarget therapy

Background

S-HM-3 is a tumor angiogenesis inhibitor with short half-life (25 min). In this present, TPGS/Solutol polymeric micelles was prepared to load together insoluble paclitaxel (PTX) and soluble S-HM-3, expecting to together deliver them to the tumor site with long-circulating, targeting function and combating multi-drug resistance (MDR).

Materials and methods

PTX and S-HM-3 loaded TPGS/Solutol micelles (PHTSm) were prepared by the method of thin-film evaporation, and characterized by dynamic light scattering, transmission electron microscope (TEM), atomic force microscopy (AFM) and releasing properties. The anticancer effect of the polymeric micelles system was evaluated and confirmed by experiments of in vitro cell uptake study, in vivo pharmacokinetics, and pharmacodynamics studies.

Results

Micelles exhibited smooth spherical morphology with 20~30 nm and low critical micelle concentration (CMC) value of 0.000124 mg/mL. Only about 30% of PTX were slowly released from micelles at 48h, which can beneficial to the long circulation in blood. The results of in vitro cell assay proved that S-HM-3 could be easier to get into MDA-MB-231 cell, and its angiogenesis inhibition ability was also enhanced after integrating into micelles. In particular, the results of in vivo studies showed that the half-life of S-HM-3 and PTX was significantly prolonged 25.27 and 5.54 folds, and their AUC_0-∞ was enhanced 129.78 and 15.65 times, respectively. Meanwhile 83.05% tumor inhibition rate of PHTSm was achieved compared with 59.99% of PTX.

Conclusions

TPGS and Solutol micelles hold promising potential to resolve the conundrum of combined therapy of cytotoxic drug and angiogenesis inhibitor with different physicochemical property and anticancer mechanism in clinical use.

Basic principles of drug delivery systems - the case of paclitaxel

Cancer is the second cause of death worldwide, exceeded only by cardiovascular diseases. The prevalent treatment currently used against metastatic cancer is chemotherapy. Among the most studied drugs that inhibit neoplastic cells from acquiring unlimited replicative ability (a hallmark of cancer) are the taxanes. They operate via a unique molecular mechanism affecting mitosis. In this review, we show this mechanism for one of them, paclitaxel, and for other (non-taxanes) anti-mitotic drugs. However, the use of paclitaxel is seriously limited (its bioavailability is <10%) due to several long-standing challenges: its poor water solubility (0.3 μg/mL), its being a substrate for the efflux multidrug transporter P-gp, and, in the case of oral delivery, its first-pass metabolism by certain enzymes. Adequate delivery methods are therefore required to enhance the anti-tumor activity of paclitaxel. Thus, we have also reviewed drug delivery strategies in light of the various physical, chemical, and enzymatic obstacles facing the (especially oral) delivery of drugs in general and paclitaxel in particular. Among the powerful and versatile platforms that have been developed and achieved unprecedented opportunities as drug carriers, microemulsions might have great potential for this aim. This is due to properties such as thermodynamic stability (leading to long shelf-life), increased drug solubilization, and ease of preparation and administration. In this review, we define microemulsions and nanoemulsions, analyze their pertinent properties, and review the results of several drug delivery carriers based on these systems.

The combined administration of parthenolide and ginsenoside CK in long circulation liposomes with targeted tLyp-1 ligand induce mitochondria-mediated lung cancer apoptosis

BACKGROUND

Combinations of natural products with low toxicities using tumor-targeting carriers may improve cancer treatment. The combined parthenolide and ginsenoside compound K (CK) within tLyp-1 liposomes, with the aim of improving the efficacy of lung cancer treatment.

RESULTS

In vitro studies in A549 human pulmonary adenocarcinoma cells demonstrated that parthenolide/CK tLyp-1 liposomes increased reactive oxygen species levels and induced mitochondrial apoptosis. It enters into cells via receptor-mediated uptake and micropinocytosis, followed by endosomal/lysosomal escape. In vivo studies illustrated that it produced a greater antitumor effect than combined administration of these compounds, with minimal toxicity.

CONCLUSION

The findings of this study indicated that combined application of natural products in nanocarriers could offer attractive therapeutic options.

Identification of a Novel Anticancer Oligopeptide from Perilla frutescens (L.) Britt. and Its Enhanced Anticancer Effect by Targeted Nanoparticles In Vitro

Objective. Perilla frutescens (L.) Brittis is a dietary herbal medicine and has anticancer effect. However, little is known about its anticancer peptides. This study is aimed at identifying cytotoxic oligopeptides which are loaded by a drug delivery system, to explore its anticancer application. Methods. The oligopeptides were isolated from enzymatic hydrolysates of Perilla seed crude protein by using ultrafiltration, gel filtration chromatography, and reversed-phase high-performance liquid chromatography (RP-HPLC). The structure of the oligopeptide was determined using a peptide sequencer, and its anticancer effect was examined by the MTT assay. PSO (Perilla seed oligopeptide), the most potent anticancer oligopeptide, was loaded by chitosan nanoparticles (NPs) modified by hyaluronic acid (HA). Then, the particle size, zeta potential, encapsulation efficiency (EE), drug loading efficiency (LE), the cumulative release rates of NPs, and its cytotoxic effect on cancer cells were investigated. Results. Three fractions were isolated by the chromatography assay. The third fraction has a broad-spectrum and the strongest anticancer effect. This fraction was further purified and identified as SGPVGLW with a molecular weight of 715 Da and named as PSO. Then, PSO was loaded by HA-conjugated chitosan to prepare HA/PSO/C NPs, which had a uniform size of 216.7 nm, a zeta potential of 35.4 mV, an EE of 38.7%, and an LE of 24.3%. HA/PSO/C NPs had a slow release rate in vitro, with cumulative release reaching to 81.1%. Compared with free PSO, HA/PSO/C NPs showed notably enhanced cytotoxicity and had the strongest potency to human glioma cell line U251. Conclusion. This study demonstrated that PSO, a novel oligopeptide from Perilla seeds, has a broad-spectrum anticancer effect and could be encapsulated by NPs, which enhanced tumor targeting cytotoxicity with obvious controlled release. Our study indicates that Perilla seeds are valuable for anticancer peptide development.

Comparison of hyaluronic acid-based micelles and polyethylene glycol-based micelles on reversal of multidrug resistance and enhanced anticancer efficacy in vitro and in vivo

Polyethylene glycol (PEG)-based block copolymer micelles and hyaluronic acid (HA)-based grafted copolymer micelles have been widely investigated in chemotherapy. In this study, to evaluate the differences among HA-based grafted polymer micelles, PEG-based block polymer micelles and the mixed of these two micelles in enhancing antitumor effects and overcoming MDR, two amphiphilic vitamin E succinate (VES) derivatives, HA VES (HA-g-VES) and PEG 2000 VES (TPGS2k), were applied as nanocarriers to prepare HA-VES micelles (HA-PMs), TPGS2k micelles (TPGS2k-PMs) and the mixed micelles (HA/TPGS2k-PMs) for the co-delivery of doxorubicin (DOX) and curcumin (Cur). With the addition of TPGS2k, the particle size of HA/TPGS2k-PMs (153.37 ± 1.00 nm) was smaller than that of HA-PMs (223.83 ± 1.84) but significantly larger than that of TPGS2k-PMs (about 20 nm). The loading efficiency of HA/TPGS2k-PMs was 7.10%, which was lower than HA-PMs (8.31 ± 0.15%) but higher than TPGS2k-PMs (4.38 ± 0.24%). In vitro, HA/TPGS2k-PMs and TPGS2k-PMs exhibited higher cytotoxicity and reversal MDR effects than HA-PMs in MCF-7/Adr cells. However, HA/TPGS2k-PMs, HA-PMs and TPGS2k-PMs all significantly improved the tumor biodistribution, the antitumor effects and reduced the side effects of DOX in 4T1-tumor-bearing mice, but these three micelles displayed no differences in vivo. Therefore, EPR passive targeting effects caused by PEGylated micelles and CD44 active targeting effects caused by HA-based micelles have no significant variance in the delivery of antitumor drugs by i.v.

Synergistic apoptotic effects of apigenin TPGS liposomes and tyroservatide: implications for effective treatment of lung cancer

To develop an alternative treatment for lung cancer, a combination of two potent chemotherapeutic agents – liposomal apigenin and tyroservatide – was developed. The therapeutic potential of this combination was investigated using A549 cells. Apigenin and tocopherol derivative-containing D-alpha-tocopheryl polyethylene glycol 1000 succinate (TPGS) liposomes might improve the delivery of apigenin to tumor cells, both in vitro and in vivo. Importantly, compared to either agent alone, the combination of apigenin TPGS liposomes and tyroservatide exhibited superior cytotoxicity, induced stronger G2 arrest, and suppressed A549 cancer cell invasion at a lower dose. The proapoptotic synergistic effects were also observed in A549 cells using terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling, flow cytometry, and Western blot analysis. More importantly, in vivo results showed that the combination of apigenin TPGS liposomes and tyroservatide exhibited tumor-growth inhibitory effects in A549 cell-bearing mice. In conclusion, our study showed that this combination therapy could serve as a promising synergistic therapeutic approach to improve outcomes in patients with lung cancer.