Encapsulation, controlled release, and antitumor efficacy of cisplatin delivered in liposomes composed of sterol-modified phospholipids

Platinum-based chemotherapy: trends in organic nanodelivery systems

Despite the investment in platinum drugs research, cisplatin, carboplatin and oxaliplatin are still the only Pt-based compounds used as first line treatments for several cancers, with a few other compounds being approved for administration in some Asian countries. However, due to the severe and worldwide impact of oncological diseases, there is an urge for improved chemotherapeutic approaches. Furthermore, the pharmaceutical application of platinum complexes is hindered by their inherent toxicity and acquired resistance. Nanodelivery systems rose as a key strategy to overcome these challenges, with recognized versatility and ability towards improving the safety, bioavailability and efficacy of the available drugs. Among the known nanocarriers, organic systems have been widely applied, taking advantage of their potential as drug vehicles. Researchers have mainly focused on the development of lipidic and polymeric carriers, including supramolecular structures, with an overall improvement of encapsulated platinum complexes. Herein, an overview of recent trends and strategies is presented, with the main focus on the encapsulation of platinum compounds into organic nanocarriers, showcasing the evolution in the design and development of these promising systems. This comprehensive review highlights formulation methods as well as characterization procedures, providing insights that may be helpful for the development of novel platinum nanocarriers aiming at future pharmaceutical applications.

Encapsulation of zingerone by self-assembling peptides derived from fish viscera: Characterization, interaction and effects on colon epithelial cells

The purpose of the present work was to encapsulate zingerone (a bioactive compound from ginger) by self-assembling peptides derived from fish viscera. The encapsulation conditions were investigated and the structure of fish peptides-zingerone complex was characterized. The interaction between zingerone and fish peptides was investigated using fluorescence spectroscopy. Further research was performed on the in vitro release of zingerone and fish peptide-zingerone as well as their antiproliferative effects on colon epithelial Caco-2 cells. The results demonstrated that zingerone can be successfully encapsulated by self-assembling peptides derived from fish viscera with high encapsulation efficiency and loading capacity. Furthermore, transmission electron microscope and confocal laser scanning microscope observations revealed the successful encapsulation of zingerone by fish viscera peptides. In addition, in vitro release and antiproliferative activity against Caco-2 cells can be significantly increased by encapsulating zingerone via peptide self-assembly. The current study advances knowledge of encapsulation of bioactive compounds through peptide self-assembly.

Calcein release from DPPC liposomes by phospholipase A2 activity: Effect of cholesterol and amphipathic copolymers

In this study, we evaluated the impact of incorporating diblock and triblock amphiphilic copolymers, as well as cholesterol into DPPC liposomes on the release of a model molecule, calcein, mediated by exogenous phospholipase A2 activity. Our findings show that calcein release slows down in the presence of copolymers at low concentration, while at high concentration, the calcein release profile resembles that of the DPPC control. Additionally, calcein release mediated by exogenous PLA2 decreases as the amount of solubilized cholesterol increases, with a maximum between 18 mol% and 20 mol%. At concentrations higher than 24 mol%, no calcein release was observed. Studies conducted on HEK-293 and HeLa cells revealed that DPPC liposomes reduced viability by only 5% and 12%, respectively, after 3 hours of incubation, while DPPC liposome in presence of 33 mol% of Cholesterol reduced viability by approximately 11% and 23%, respectively, during the same incubation period. For formulations containing copolymers at low and high concentrations, cell viability decreased by approximately 20% and 40%, respectively, after 3 hours of incubation. Based on these preliminary results, we can conclude that the presence of amphiphilic copolymers at low concentration can be used in the design of new DPPC liposomes, and together with cholesterol, they can modulate liposome stabilization. The new formulations showed low cytotoxicity in HEK-293 cells, and it was observed that calcein release depended entirely on PLA2 activity and the presence of calcium ions.

Toward the boosted loading of cisplatin drug into liposome nanocarriers

Current challenges in oncology are largely associated with the need to improve the effectiveness of cancer treatment and to reduce drug's side effects. An effective strategy to cope with these challenges is behind designing and developing drug delivery systems based on smart nanomaterials and approved anticancer drugs. The present study offers a novel and straightforward approach to efficiently load the cisplatin drug into the newly constructed liposome-based nanosystems as well a reliable technique for monitoring this process based on capillary electrophoresis hyphenated with inductively coupled plasma tandem mass spectrometry. The proposed drug-loading methodology comprises liposome formation via a simple ethanol-injection method and propels increased drug encapsulation using tailor-made freeze-thawing or lyophilization-hydration procedures. To optimize liposome generation and drug encapsulation, the effects of dilution medium and liposome composition (types of phospholipids and their percentage ratio) have been investigated in detail. It was shown that modest alterations of the composition of three-component phospholipid liposomes and parameters of the freeze-thawing procedure have a strong impact on the formation of cisplatin-liposome systems. The obtained cisplatin-liposome formulation features a remarkable degree of drug encapsulation, over 100 mg L-1, and holds promise for further preclinical development as a potent drug-delivery platform.

Delivery of Chemotherapy Agents and Nucleic Acids with pH-Dependent Nanoparticles

With less than one percent of systemically injected nanoparticles accumulating in tumors, several novel approaches have been spurred to direct and release the therapy in or near tumors. One such approach depends on the acidic pH of the extracellular matrix and endosomes of the tumor. With an average pH of 6.8, the extracellular tumor matrix provides a gradient for pH-responsive particles to accumulate, enabling greater specificity. Upon uptake by tumor cells, nanoparticles are further exposed to lower pHs, reaching a pH of 5 in late endosomes. Based on these two acidic environments in the tumor, various pH-dependent targeting strategies have been employed to release chemotherapy or the combination of chemotherapy and nucleic acids from macromolecules such as the keratin protein or polymeric nanoparticles. We will review these release strategies, including pH-sensitive linkages between the carrier and hydrophobic chemotherapy agent, the protonation and disruption of polymeric nanoparticles, an amalgam of these first two approaches, and the release of polymers shielding drug-loaded nanoparticles. While several pH-sensitive strategies have demonstrated marked antitumor efficacy in preclinical trials, many studies are early in their development with several obstacles that may limit their clinical use.

Nanoparticles in the diagnosis and treatment of cancer metastases: Current and future perspectives

Metastasis accounts for greater than 90% of cancer-related deaths. Despite recent advancements in conventional chemotherapy, immunotherapy, targeted therapy, and their rational combinations, metastatic cancers remain essentially untreatable. The distinct obstacles to treat metastases include their small size, high multiplicity, redundancy, therapeutic resistance, and dissemination to multiple organs. Recent advancements in nanotechnology provide the numerous applications in the diagnosis and prophylaxis of metastatic diseases, including the small particle size to penetrate cell membrane and blood vessels and their capacity to transport complex molecular 'cargo' particles to various metastatic regions such as bones, brain, liver, lungs, and lymph nodes. Indeed, nanoparticles (NPs) have demonstrated a significant ability to target specific cells within these organs. In this regard, the purpose of this review is to summarize the present state of nanotechnology in terms of its application in the diagnosis and treatment of metastatic cancer. We intensively reviewed applications of NPs in fluorescent imaging, PET scanning, MRI, and photoacoustic imaging to detect metastasis in various cancer models. The use of targeted NPs for cancer ablation in conjunction with chemotherapy, photothermal treatment, immuno therapy, and combination therapy is thoroughly discussed. The current review also highlights the research opportunities and challenges of leveraging engineering technologies with cancer cell biology and pharmacology to fabricate nanoscience-based tools for treating metastases.

Research Status and Prospect of Non-Viral Vectors Based on siRNA: A Review

Gene therapy has attracted much attention because of its unique mechanism of action, non-toxicity, and good tolerance, which can kill cancer cells without damaging healthy tissues. siRNA-based gene therapy can downregulate, enhance, or correct gene expression by introducing some nucleic acid into patient tissues. Routine treatment of hemophilia requires frequent intravenous injections of missing clotting protein. The high cost of combined therapy causes most patients to lack the best treatment resources. siRNA therapy has the potential of lasting treatment and even curing diseases. Compared with traditional surgery and chemotherapy, siRNA has fewer side effects and less damage to normal cells. The available therapies for degenerative diseases can only alleviate the symptoms of patients, while siRNA therapy drugs can upregulate gene expression, modify epigenetic changes, and stop the disease. In addition, siRNA also plays an important role in cardiovascular diseases, gastrointestinal diseases, and hepatitis B. However, free siRNA is easily degraded by nuclease and has a short half-life in the blood. Research has found that siRNA can be delivered to specific cells through appropriate vector selection and design to improve the therapeutic effect. The application of viral vectors is limited because of their high immunogenicity and low capacity, while non-viral vectors are widely used because of their low immunogenicity, low production cost, and high safety. This paper reviews the common non-viral vectors in recent years and introduces their advantages and disadvantages, as well as the latest application examples.

The comparison of biodistribution of glutathione PEGylated nanoliposomal doxorubicin formulations prepared by pre-insertion and post-insertion methods for brain delivery in normal mice

Several obstacles limit the efficacy of brain tumour treatment, most notably the blood-brain barrier (BBB), which prevents the brain uptake of the majority of accessible medicines due to tight junctions. The presence of glutathione (GSH) receptors on the BBB surface has been demonstrated in numerous papers; consequently, products containing glutathione as a targeting ligand coupled with nanoliposomes are used to enhance drug delivery across the BBB. Here, the 5% pre-inserted PEG2000-GSH PEGylated liposomal doxorubicin was conducted according to 2B3-101 being tested in clinical trials. In addition, PEGylated nanoliposomal doxorubicin connected to the spacer-GSH targeting ligand (GSGGCE) and the PEG3400 was conducted using post-insertion method. Next, in vivo biodistribution of the produced formulations was tested on healthy mice to see if GSGGCE, as the targeted ligand, could cross the BBB compared to 5% pre-inserted PEG2000-GSH and Caelyx^® . Compared to the pre-inserted formulation and Caelyx^® , the post-inserted formulations' concentration was lower in the heart and higher in brain tissues, resulting in boosting the brain concentration of accumulated doxorubicin with fewer possible side effects, including cardiotoxicity. In comparison to the pre-insertion procedure, the post-insertion method is easier, faster, and more cost-effective. Moreover, employing PEG3400 and the post-insertion approach in the PEG3400-GSGGCE liposomal formulations was found to be effective in crossing the BBB.

The role of size in PEGylated liposomal doxorubicin biodistribution and anti-tumour activity

The size of nanoliposome‐encapsulated drugs significantly affects their therapeutic efficacy, biodistribution, targeting ability, and toxicity profile for the cancer treatment. In the present study, the biodistribution and anti‐tumoral activity of PEGylated liposomal Doxorubicin (PLD) formulations with different sizes were investigated. First, 100, 200, and 400 nm PLDs were prepared by remote loading procedure and characterised for their size, zeta potential, encapsulation efficacy, and release properties. Then, in vitro cellular uptake and cytotoxicity were studied by flow cytometry and MTT assay, and compared with commercially available PLD Caelyx^®. In vivo studies were applied on BALB/c mice bearing C26 colon carcinoma. The cytotoxicity and cellular uptake tests did not demonstrate any statistically significant differences between PLDs. The biodistribution results showed that Caelyx^® and 100 nm liposomal formulations had the most doxorubicin (Dox) accumulation in the tumour tissue and, as a result, considerably suppressed tumour growth compared with 200 and 400 nm PLDs. In contrast, larger nanoparticles (200 and 400 nm formulations) had more accumulation in the liver and spleen. This study revealed that 90 nm Caelyx^® biodistribution profile led to the stronger anti‐tumour activity of the drug and hence significant survival extension, and showed the importance of vesicle size in the targeting of nanoparticles to the tumour microenvironment for the treatment of cancer.

Amino acid coordination complex mediates cisplatin entrapment within PEGylated liposome: An implication in colorectal cancer therapy

Cis-Diaminedichloroplatinum (cisplatin, CDDP) remained among the most widely used anti-cancer agents; however, management of the dose-limiting side effects is still a great hurdle to its therapeutic potential. In the framework of this investigation, novel approach was developed for CDDP encasement within liposome based on the formation of a coordination bond between the platinum (II) atom and a carboxylic group in aspartic acid (AA) and glutamic acid (GA). We have also compared two methods of preparation based on equilibration and conventional lipid film hydration. For this, first FTIR spectra of the conjugates confirmed coordination bond between Pt and the carboxylate moieties. The PEGylated liposomes composed of HSPC, cholesterol and DPPG had a size of 134 to 197 nm and negative zeta potential (-14.20 to -20.90 mv). Cytotoxicity study revealed IC₅₀ values of <7 µg/ml for liposomes. In vivo plasma retention following iv administration indicated the potential of liposome in maintaining cisplatin levels within the circulation, while free cisplatin and cisplatin conjugates were promptly eliminated. Anti-tumor efficacy studies following iv injections at 3 mg/kg cisplatin weekly for three weeks in C26 tumor bearing BALB/c mice demonstrated the potential of the cisplatin liposomes in tumor growth inhibition. Pt-complexes were not as effective as liposomal formulations showing the crucial role of liposomes in maintaining cisplatin levels within blood circulation. Overall, the developed cisplatin liposome seems to be a promising therapeutic approach for targeting solid tumors.

Liposome-Tethered Gold Nanoparticles Triggered by Pulsed NIR Light for Rapid Liposome Contents Release and Endosome Escape

Remote triggering of contents release with micron spatial and sub-second temporal resolution has been a long-time goal of medical and technical applications of liposomes. Liposomes can sequester a variety of bioactive water-soluble ions, ligands and enzymes, and oligonucleotides. The bilayer that separates the liposome interior from the exterior solution provides a physical barrier to contents release and degradation. Tethering plasmon-resonant, hollow gold nanoshells to the liposomes, or growing gold nanoparticles directly on the liposome exterior, allows liposome contents to be released by nanosecond or shorter pulses of near-infrared light (NIR). Gold nanoshells or nanoparticles strongly adsorb NIR light; cells, tissues, and physiological media are transparent to NIR, allowing penetration depths of millimeters to centimeters. Nano to picosecond pulses of NIR light rapidly heat the gold nanoshells, inducing the formation of vapor nanobubbles, similar to cavitation bubbles. The collapse of the nanobubbles generates mechanical forces that rupture bilayer membranes to rapidly release liposome contents at the preferred location and time. Here, we review the syntheses, characterization, and applications of liposomes coupled to plasmon-resonant gold nanostructures for delivering a variety of biologically important contents in vitro and in vivo with sub-micron spatial control and sub-second temporal control.

Nanomedicine at the crossroads - A quick guide for IVIVC

For many years, nanomedicine is pushing the boundaries of drug delivery. When applying these novel therapeutics, safety considerations are not only a key concern when entering clinical trials but also an important decision point in product development. Standing at the crossroads, nanomedicine may be able to escape the niche markets and achieve wider acceptance by the pharmaceutical industry. While there is a new generation of drug delivery systems, the extracellular vesicles, standing on the starting line, unresolved issues and new challenges emerge from their translation from bench to bedside. Some key features of injectable nanomedicines contribute to the predictability of the pharmacological and toxicological effects. So far, only a few of the physicochemical attributes of nanomedicines can be justified by a direct mathematical relationship between the in vitro and the in vivo responses. To further develop extracellular vesicles as drug carriers, we have to learn from more than 40 years of clinical experience in liposomal delivery and pass on this knowledge to the next generation. Our quick guide discusses relationships between physicochemical characteristics and the in vivo response, commonly referred to as in vitro-in vivo correlation. Further, we highlight the key role of computational methods, lay open current knowledge gaps, and question the established design strategies. Has the recent progress improved the predictability of targeted delivery or do we need another change in perspective?

Coupling EGFR-Antagonistic Affibody Enhanced Therapeutic Effects of Cisplatin Liposomes in EGFR-expressing Tumor Models

Epidermal growth factor receptor (EGFR) is an efficient target for cancer therapy. In this study, a high-affinity EGFR-antagonistic affibody (Z_EGFR) molecule coupled with cisplatin-loaded PEGylated liposomes (LS-DDP) was applied to actively target EGFR⁺ A431 tumor cells in vitro and in vivo. The LS-DDP coupled with Z_EGFR (AS-DDP) had an average size of 140.01 ± 0.84 nm, low polydispersity, a zeta potential of -13.40 ± 0.8 mV, an acceptable encapsulation efficiency of 17.30 ± 1.35%, and released cisplatin in a slow-controlled manner. In vitro, AS-DDP demonstrated a higher amount of platinum intracellular uptake by A431 cells than LS-DDP. The IC50 value of AS-DDP (9.02 ± 1.55 μg/ml) was much lower than that of LS-DDP (16.44 ± 0.87 μg/ml), indicating that the anti-tumor effects of AS-DDP were remarkable due to the modification of Z_EGFR. In vivo, the concentration of AS-DDP in the tumor site increased more than 1.76-fold, while an increase in apoptotic cells at 48 h compared to the LS-DDP was also observed, illustrating that AS-DDP possessed excellent tumor-targeting efficiency. As a result, the targeted nano-liposomes achieved greater tumor suppression. Therefore, selective targeting of LS-DDP coupled with Z_EGFR enhanced the anti-tumor effects and appeared to be a promising strategy for the treatment of EGFR⁺ tumors.

Nanoencapsulation of Hirudo medicinalis proteins in liposomes as a nanocarrier for inhibiting angiogenesis through targeting VEGFA in the Breast cancer cell line (MCF-7)

Introduction: Breast cancer is the most serious cause of women’s death throughout the world. Using nanocarrier vehicles to the exact site of cancer upgrades the therapeutic efficiency of the drugs. Capsulation of active proteins in the vesicular liposomes’ hydrophilic core is essential to develop a therapeutic protein carrier system. We aimed to encapsulate the medicinal leech saliva extract (LSE) and assess the inhibition of angiogenesis of breast cancer cells by targeting vascular endothelial growth factor A (VEGFA). Methods: In this research, enhanced formulation of liposomal protein was determined by zeta potential analysis, droplet size, drug release assay, and transmission electron microscopy (TEM). Furthermore, a cytotoxicity assay of liposomal LSE was performed to determine the cytotoxic activity of components. For assessing the expression of VEGFA, P53, and hypoxia-inducible factor subunit alpha (HIF1a) genes, Real-Time PCR was applied. Results: Nano liposome was chosen as an enhanced formulation due to its much smaller size (46.23 nm). Liposomal LSE had more practical actions on the MCF-7 cells. As noticed by DAPI staining, apoptosis was extensively greater in treated MCF-7 cells. Wound healing assay demonstrated that MCF-7 cells could not sustain growth at the presence of liposomal LSE and expression of the VEGFA gene was declined in treated cells. Downregulation of VEGFA was evaluated with western blotting technique. Conclusion: It can be concluded that our investigation of the tests confirmed the fact that nano liposomal LSE is a novel promising formulation for anticancer drugs and can significantly improve the penetration of protein drugs to cancer cells.

Co-Encapsulation of Fisetin and Cisplatin into Liposomes for Glioma Therapy: From Formulation to Cell Evaluation

(1) Background: Glioblastoma (GBM) is the most frequent cerebral tumor. It almost always relapses and there is no validated treatment for second-line GBM. We proposed the coencapsulation of fisetin and cisplatin into liposomes, aiming to (i) obtain a synergistic effect by combining the anti-angiogenic effect of fisetin with the cytotoxic effect of cisplatin, and (ii) administrate fisetin, highly insoluble in water. The design of a liposomal formulation able to encapsulate, retain and deliver both drugs appeared a challenge. (2) Methods: Liposomes with increasing ratios of cholesterol/DOPC were prepared and characterized in term of size, PDI and stability. The incorporation of fisetin was explored using DSC. The antiangiogneic and cytotoxic activities of the selected formulation were assayed in vitro. (3) Results: We successfully developed an optimized liposomal formulation incorporating both drugs, composed by DOPC/cholesterol/DODA-GLY-PEG2000 at a molar ratio of 75.3/20.8/3.9, with a diameter of 173 ± 8 nm (PDI = 0.12 ± 0.01) and a fisetin and cisplatin drug loading of 1.7 ± 0.3% and 0.8 ± 0.1%, respectively, with a relative stability over time. The maximum incorporation of fisetin into the bilayer was determined at 3.2% w/w. Then, the antiangiogenic activity of fisetin was maintained after encapsulation. The formulation showed an additive effect of cisplatin and fisetin on GBM cells; (4) Conclusions: The developed co-loaded formulation was able to retain the activity of fisetin, was effective against GBM cells and is promising for further in vivo experimentations.

A Mini-Review on Nano Technology in the Tumour Targeting Strategies: Drug Delivery to Cancer Cells

BACKGROUND

Recently, the application of cancer nanotechnology-based drug delivery to cancer cells has arisen as an important method to resolve multiple molecular, biophysical, and biochemical obstacles, which the body is preparing to resist against the productive implementation of chemotherapeutic medications. Drug delivery technologies focused on nanoparticles, which have resolved some of the drawbacks of conventional chemotherapy as, decreased drug viscosity, chemo-resistance, precise malignity, limited medicative measures with low oral bioactivity. Due to their adjustable size and surface properties, the half-life period of a drug can be increased in the bloodstream.

OBJECTIVE

The aim of the current study is to collect and document the data available on the drug delivery system for anticancer drugs. The present study includes some of the drug carriers like liposomes, carbon dots, micelles, carbon nanotubes, magnetic nanoparticles, etc. Methods: To write this review, an exhaustive literature survey was carried out using relevant work published in various SCI, Scopus, and non-SCI indexed journals. The different search engines used to download the research/ review papers are Google search, PubMed, Science Direct, Google Scholar, Scientific Information Database and Research Gate, etc. Results: Nanotechnology offers better pharmacokinetics, reduces the systematic toxicities related to the chemotherapies and a better route of drug administration. In the analysis, we critically highlight recent studies on carcinoma-fighting nanotechnology.

CONCLUSION

In the present study, different kinds of nano-based drug delivery systems have been discussed along with their characteristic features, the encapsulation of anticancer agents into different types of nanometresized vehicles and their general mechanism.

Improving anti-tumour efficacy of PEGylated liposomal doxorubicin by dual targeting of tumour cells and tumour endothelial cells using anti-p32 CGKRK peptide

The aim of this study was to surface-functionalize PEGylated liposomal doxorubicin (PLD) using anti-p32 CGKRK peptide to evaluate its anti-angiogenic and anti-tumour activities. CGKRK was conjugated to DSPE-mPEG₂₀₀₀-maleimide and post-inserted into PLD at 25, 50, 100, 200 and 400 peptides per each liposome and characterised for their size, zeta potential, drug loading, release properties; and cell binding, cell uptake and cytotoxicity on three C26, 4T1 and human umbilical vein endothelial cell (HUVEC) cell lines. The in vitro results indicated the better efficiency of the PLD-100 (PLD with 100 CGKRK) formulation on 4T1 and HUVEC cell lines. The results of anti-tube formation and spheroid assay indicated the efficiencies of the PLD-100 formulation compared with Caelyx^® in vitro. The in vivo studies indicated the higher tumour accumulation of PLD-100 formulation in comparison with Caelyx^® which also implied the higher survival rates in mice treated with PLD-100 formulation. Histological evaluations demonstrated that PLD-100 had no side-effects on major organs. In conclusion, the results of this study indicated that PLD-CGKRK- could efficiently target endothelial and tumour parenchymal cells which enhance the therapeutic efficacy of PLD and merits further investigation.

Optimization of the silica-gel adsorption technique for the extraction of phytosterol glycosides from soybean lecithin powder using response surface methodology and artificial neural network models

Phytosterol glycosides (PGs), comprising both acylated steryl glycosides (ASGs) and steryl glycosides (SGs), are active ingredients with benefits for human use. Here, we aimed to optimize the silica-gel adsorption technique for the extraction of PGs from soybean lecithin powder, which contains 5 to 10% of these glycolipids. Both response surface methodology (RSM) and artificial neural networks (ANNs) were applied to optimize the PG extraction parameters (X1 = silica-gel dosage, X2 = adsorption temperature, and X3 = lecithin concentration) for high-purity phospholipid and PG production, and their prediction and optimization accuracies were compared. Although both models fitted well with the experimental data, the ANN model demonstrated better accuracy for predicting and optimizing the conditions using four interrelated dependent variables (Y1 = phospholipid yield, Y2 = ASG recovery, Y3 = SG recovery, and Y4 = PG purity) and had a higher coefficient of determination and lower root mean square error and absolute average deviation. After digitally setting the percentages of the four dependent variables for phospholipid and PG production, the ANN-optimized phospholipid product (Y1 = 88.07%, Y2 = 98.89%, Y3 = 100%, and Y4 = 49.03%) was acquired at X1 = 3.54 g/g, X2 = 26 °C, and X3 = 43 mg/mL, whereas the PG product (Y1 = 83.83%, Y2 = 97.64%, Y3 = 100%, and Y4 = 59.21%) was obtained at X1 = 2.00 g/g, X2 = 28.38 °C, and X3 = 41 mg/mL. In conclusion, the ANN method was better than RSM for the optimization of the silica-gel adsorption technique for PG extraction from soybean lecithin powder. PRACTICAL APPLICATION: This paper lays a theoretical foundation for the optimization of the industrial production of phytosterol glycosides and the comprehensive utilization of lecithin resources.

Mesenchymal Stem Cells As Guideposts for Nanoparticle-Mediated Targeted Drug Delivery in Ovarian Cancer

Nanocarriers have been extensively utilized for the systemic targeting of various solid tumors and their metastases. However, current drug delivery systems, in general, suffer from a lack of selectivity for tumor cells. Here, we develop a novel two-step targeting strategy that relies on the selective accumulation of targetable synthetic receptors (i.e., azide moieties) in tumor tissues, followed by delivery of drug-loaded nanoparticles having a high binding affinity for these receptors. Mesenchymal stem cells (MSCs) were used as vehicles for the tumor-specific accumulation of azide moieties, while dibenzyl cyclooctyne (DBCO) was used as the targeting ligand. Biodistribution and antitumor efficacy studies were performed in both orthotopic metastatic and patient-derived xenograft (PDX) tumor models of ovarian cancer. Our studies show that nanoparticles are retained in tumors at a significantly higher concentration in mice that received azide-labeled MSCs (MSC-Az). Furthermore, we observed significantly reduced tumor growth (p < 0.05) and improved survival in mice receiving MSC-Az along with paclitaxel-loaded DBCO-functionalized nanoparticles compared to controls. These studies demonstrate the feasibility of a two-step targeting strategy for efficient delivery of concentrated chemotherapy for treating solid tumors.

Targeting drug delivery system for platinum(Ⅳ)-Based antitumor complexes

Classical platinum(II) anticancer agents are widely-used chemotherapeutic drugs in the clinic against a range of cancers. However, severe systemic toxicity and drug resistance have become the main obstacles which limit their application and effectiveness. Because divalent cisplatin analogues are easily destroyed in vivo, their bioavailability is low and no selective to tumor tissues. The platinum(IV) prodrugs are attractive compounds for cancer treatment because they have great advantages, e.g., higher stability in biological media, aqueous solubility and no cross-resistance with cisplatin, which may become the next generation of platinum anticancer drugs. In addition, platinum(IV) drugs could be taken orally, which could be more acceptable to cancer patients, breaking the current situation that platinum(II) drugs can only be given by injection. The coupling of platinum(IV) complexes with tumor targeting groups avoids the disadvantages such as instability in blood, irreversible binding to plasma proteins, rapid renal clearance, and non-specific distribution in normal tissues. Because of the above advantages, the combination of platinum complexes and tumor targeting groups has become the hottest field in the research and development of new platinum drugs. These approaches can be roughly categorized into two groups: active and passive targeted strategies. This review concentrates on various targeting and delivery strategies for platinum(IV) complexes to improve the efficacy and reduce the side effects of platinum-based anticancer drugs. We have made a summary of the related articles on platinum(IV) targeted delivery in recent years. We believe the results of the studies described in this review will provide new ideas and strategies for the development of platinum drugs.

Enhanced Efficacy of PEGylated Liposomal Cisplatin: In Vitro and In Vivo Evaluation

This study aims to evaluate the potency of cisplatin (Cispt)-loaded liposome (LCispt) and PEGylated liposome (PLCispt) as therapeutic nanoformulations in the treatment of bladder cancer (BC). Cispt was loaded into liposomes using reverse-phase evaporation method, and the formulations were characterized using dynamic light scattering, scanning electron microscopy, dialysis membrane, and Fourier-transform infrared spectroscopy (FTIR) methods. The results showed that the particles were formed in spherical monodispersed shapes with a nanoscale size (221–274 nm) and controlled drug release profile. The cytotoxicity effects of LCispt and PLCispt were assessed in an in vitro environment, and the results demonstrated that PLCispt caused a 2.4- and 1.9-fold increase in the cytotoxicity effects of Cispt after 24 and 48 h, respectively. The therapeutic and toxicity effects of the formulations were also assessed on BC-bearing rats. The results showed that PLCispt caused a 4.8-fold increase in the drug efficacy (tumor volume of 11 ± 0.5 and 2.3 ± 0.1 mm³ in Cispt and PLCispt receiver rats, respectively) and a 3.3-fold decrease in the toxicity effects of the drug (bodyweight gains of 3% and 10% in Cispt and PLCispt receiver rats, respectively). The results of toxicity were also confirmed by histopathological studies. Overall, this study suggests that the PEGylation of LCispt is a promising approach to achieve a nanoformulation with enhanced anticancer effects and reduced toxicity compared to Cispt for the treatment of BC.

Collagenase Nanoparticles Enhance the Penetration of Drugs into Pancreatic Tumors

Overexpressed extracellular matrix (ECM) in pancreatic ductal adenocarcinoma (PDAC) limits drug penetration into the tumor and is associated with poor prognosis. Here, we demonstrate that a pretreatment based on a proteolytic-enzyme nanoparticle system disassembles the dense PDAC collagen stroma and increases drug penetration into the pancreatic tumor. More specifically, the collagozome, a 100 nm liposome encapsulating collagenase, was rationally designed to protect the collagenase from premature deactivation and prolonged its release rate at the target site. Collagen is the main component of the PDAC stroma, reaching 12.8 ± 2.3% vol in diseased mice pancreases, compared to 1.4 ± 0.4% in healthy mice. Upon intravenous injection of the collagozome, ∼1% of the injected dose reached the pancreas over 8 h, reducing the level of fibrotic tissue to 5.6 ± 0.8%. The collagozome pretreatment allowed increased drug penetration into the pancreas and improved PDAC treatment. PDAC tumors, pretreated with the collagozome followed by paclitaxel micelles, were 87% smaller than tumors pretreated with empty liposomes followed by paclitaxel micelles. Interestingly, degrading the ECM did not increase the number of circulating tumor cells or metastasis. This strategy holds promise for degrading the extracellular stroma in other diseases as well, such as liver fibrosis, enhancing tissue permeability before drug administration.

Recent progress in nanotechnology-based novel drug delivery systems in designing of cisplatin for cancer therapy: an overview

Cisplatin cis-(diammine)dichloridoplatinum(II) (CDDP) is the first platinum-based complex approved by the food and drug administration (FDA) of the United States (US). Cisplatin is the first line chemotherapeutic agent used alone or combined with radiations or other anti-cancer agents for a broad range of cancers such as lung, head and neck. Aroplatin™, Lipoplatin™ and SPI-077 are PEGylated liposome-based nano-formulations that are still under clinical trials. They have many limitations, for example, poor aqueous solubility, drug resistance and toxicities, which can be overcome by encapsulating the cisplatin in Nemours nanocarriers. The extensive literature from different electronic databases covers the different nano-delivery systems that are developed for cisplatin. This review critically emphasizes on the recent advancement, development, innovations and updated literature reported for different carrier systems for CDDP.

Influence of geometric isomerism on the binding of platinum anticancer agents with phospholipids

Reported herein is a detailed NMR and DFT study of the interaction of the 15N-labelled dinuclear platinum anticancer compound [{cis-PtCl(NH3)2}2{μ-H2N(CH2)6NH2}]2+ (15N-1, 1,1/c,c) with 1,2-dihexanoyl-sn-glycero-3-phosphate (DHPA), as a comparison with an earlier study of the interaction of the same water-soluble phospholipid fragment with the geometric trans isomer (1,1/t,t). The reaction of 15N-1 with the sodium salt of DHPA was studied at 298 K, pH ∼ 5.6, by [1H,15N] HSQC 2D NMR spectroscopy. The NMR data, supported by DFT models, provide evidence that the monofunctional DHPA adduct of 15N-1 exists in two conformational forms, with different orientation of the (CH2)6 linker; one has an interaction between the unbound {PtN3Cl} moiety and the coordinated DHPA molecule. Similarly, two bifunctional adduct conformers are identified, in which one has an interaction between the phosphate groups of the two bound DHPA molecules. When compared to the previously reported reactions of 1,1/t,t with DHPA, equilibrium conditions of the 1,1/c,c reaction are reached more slowly (120 h), similar to the reaction with phosphate. The rate constant for the first step of DHPA binding (kL) is slightly lower (1.6 fold) for the cis-compared to the trans-isomer, whereas the rate constant for the reverse reaction is 4-fold lower, resulting in a much greater proportion of DHPA bound species at equilibrium.

Liposomal Drug Delivery Systems and Anticancer Drugs

Cancer is a life-threatening disease contributing to ~3.4 million deaths worldwide. There are various causes of cancer, such as smoking, being overweight or obese, intake of processed meat, radiation, family history, stress, environmental factors, and chance. The first-line treatment of cancer is the surgical removal of solid tumours, radiation therapy, and chemotherapy. The systemic administration of the free drug is considered to be the main clinical failure of chemotherapy in cancer treatment, as limited drug concentration reaches the tumour site. Most of the active pharmaceutical ingredients (APIs) used in chemotherapy are highly cytotoxic to both cancer and normal cells. Accordingly, targeting the tumour vasculatures is essential for tumour treatment. In this context, encapsulation of anti-cancer drugs within the liposomal system offers secure platforms for the targeted delivery of anti-cancer drugs for the treatment of cancer. This, in turn, can be helpful for reducing the cytotoxic side effects of anti-cancer drugs on normal cells. This short-review focuses on the use of liposomes in anti-cancer drug delivery.

Cisplatin liposome and 6-amino nicotinamide combination to overcome drug resistance in ovarian cancer cells

Ovarian cancer is an aggressive and lethal cancer usually treated by cytoreductive surgery followed by chemotherapy. Unfortunately, after an initial response, many patients relapse owing mainly to the development of resistance against the standard chemotherapy regime, carboplatin/paclitaxel, which is also affected by heavy side effects. In view to addressing such issues here, an association of liposomal cisplatin with 6-amino nicotinamide is investigated. It is known that resistant cells increase their demand for glucose, which is partially redirected toward the pentose phosphate pathway (PPP). Interestingly, we have found that also a cisplatin-resistant subclone of the ovarian cancer cells IGROV1 switch their metabolism toward the glycolytic pathway and rely on PPP to elude cisplatin cytotoxicity. The drug 6-amino nicotinamide, an inhibitor of the enzyme glucose-6-phosphate dehydrogenase (the rate-limiting step of the PPP) can restore the sensitivity of resistant cells to cisplatin. Then, to reduce the toxicity of cisplatin and prolong its action, a lyophilized stealth liposomal formulation of cisplatin was developed. The combination treatment of liposomal cisplatin and 6-amino nicotinamide showed promising cytotoxic activities in drug-resistant cells and a prolonged pharmacokinetics in rats, thus opening the way for a new therapeutic option against ovarian cancer.