Developing a highly stable PLGA-mPEG nanoparticle loaded with cisplatin for chemotherapy of ovarian cancer

Engineered and Mimicked Extracellular Nanovesicles for Therapeutic Delivery

Exosomes are spherical extracellular nanovesicles with an endosomal origin and unilamellar lipid-bilayer structure with sizes ranging from 30 to 100 nm. They contain a large range of proteins, lipids, and nucleic acid species, depending on the state and origin of the extracellular vesicle (EV)-secreting cell. EVs' function is to encapsulate part of the EV-producing cell content, to transport it through biological fluids to a targeted recipient, and to deliver their cargos specifically within the aimed recipient cells. Therefore, exosomes are considered to be potential biological drug-delivery systems that can stably deliver their cargo into targeted cells. Various cell-derived exosomes are produced for medical issues, but their use for therapeutic purposes still faces several problems. Some of these difficulties can be avoided by resorting to hemisynthetic approaches. We highlight here the uses of alternative exosome-mimes involving cell-membrane coatings on artificial nanocarriers or the hybridization between exosomes and liposomes. We also detail the drug-loading strategies deployed to make them drug-carrier systems and summarize the ongoing clinical trials involving exosomes or exosome-like structures. Finally, we summarize the open questions before considering exosome-like disposals for confident therapeutic delivery.

Use of nanoparticles in animal models for prostate cancer treatment: a systematic review

PURPOSE

To conduct a systematic review of nanoparticles' use in the treatment of prostate cancer in animals.

METHODS

A systematic review was conducted in the databases PubMed, Scientific Electronic Library Online (SciELO), Latin American and Caribbean Health Sciences Literature (LILACS), Cochrane Library, and EMBASE, and the descriptors were chosen based on terms indexed in Health Sciences Descriptors (DeCS)/Medical Subject Headings (MESH), which are: nanoparticles, nanomedicine, and prostate cancer. The systematic review protocol was registered in the International Prospective Register of Systematic Reviews (PROSPERO) with ID CRD42021271008.

RESULTS

A total of 3,897 articles was chosen; after reading the inclusion and exclusion criteria, six scientific articles with themes involving nanoparticles carrying medications were reached. Among the nanoparticles found, there were carboxymethylcellulose polymer, micellar casein nanoparticles, liquid crystal nanoparticles, serum albumin nanoparticles, and poly(ethylene glycol)-block-polylactide (mPEG-PLA) conjugated nanoparticles encapsulating cabazitaxel, docetaxel, and flutamide, which were nanoparticles used to treat prostate cancer in animals.

CONCLUSIONS

Through using nanoparticles to encapsulate medications for treating prostate cancer in animals, studies show a decrease in weight and tumor reduction, with nanoparticles resulting in greater survival time than free medications. The improved permeability and retention effect of nanoparticles in the bloodstream contribute to their effectiveness.

Redox/pH-responsive hollow manganese dioxide nanoparticles for thyroid cancer treatment

The nano drug delivery system MnO2/CDDP@PDA-Cy5.5 was synthesized in this study to increase the efficacy of Cisplatin (CDDP) on thyroid cancer and alleviate the damage to normal tissue, with the aim of enhancing the anti-cancer efficacy, increasing the drug load, optimizing the control of drug release, and alleviating the systemic toxicity arising from drug off-target. On that basis, high efficacy and low toxicity win-win can be obtained. In this study, hollow manganese dioxide nanoparticles (MnO2 NPs) were prepared based on the template method. CDDP was loaded into the hollow cavity and then modified with polydopamine (PDA) and Cy5.5, with the aim of obtaining the nano-drug loading system MnO2/CDDP@PDA-Cy5.5 NPs. The NPs precisely delivered drugs by intelligently responding to the tumor microenvironment (TME). As indicated by the release curves, the NPs release CDDP rapidly by inducing the decomposition of PDA and MnO2 under acidic or redox conditions, and Magnetic resonance imaging (MRI) contrast agent Mn2+ was generated. The results of the in vivo MRI studies suggested that T1 contrast at the tumor site was notably enhanced under the Enhanced permeability and retention (EPR) effect. After the intravenous administration, the effective tumor accumulation exhibited by the NPs was confirmed by magnetic resonance imaging as a function of time. Compared with free CDDP, the in vivo therapeutic effect was remarkably increased. As indicated by the above-described results, MnO2/CDDP@PDA-Cy5.5 NPs is a drug delivery system exhibiting diagnostic and therapeutic functions.

Chronic exposure to nitric oxide sensitizes prostate cancer cells and improved ZnO/CisPt NPs cytotoxicity and selectivity

The co-therapy of common chemotherapeutics with nitric oxide (NO), an endogenous signaling molecule, is proposed as an alternative to sensitize cancer cells and enhance treatments' efficacy. Herein, we have synthesized cisplatin-releasing zinc oxide nanoparticles (ZnO/CisPt NPs), which promoted a sustained and pH targeted release, able to release a higher amount of CisPt at tumor microenvironment conditions. This material was combined with a chronic NO treatment, at low concentration, in prostate cancer cells (PC3). NO treatment enhanced the S-NO concentration in PC3 cells, suggesting the nitrosylation or transnitrosylation processes enhancement, which are directly related to S-NO binding to proteins, function alterations and cancer cells death. Indeed, these mechanisms directly impacted the cytotoxic effect of ZnO/CisPt NPs, inducing a 30 % higher viability reduction of PC3 cells after NO treatment, along with a higher selectivity index when compared to normal human fibroblasts (FN1).

Lysosomal nanotoxicity: Impact of nanomedicines on lysosomal function

Although several nanomedicines got clinical approval over the past two decades, the clinical translation rate is relatively small so far. There are many post-surveillance withdrawals of nanomedicines caused by various safety issues. For successful clinical advancement of nanotechnology, it is of unmet need to realize cellular and molecular foundation of nanotoxicity. Current data suggest that lysosomal dysfunction caused by nanoparticles is emerging as the most common intracellular trigger of nanotoxicity. This review analyzes prospect mechanisms of lysosomal dysfunction-mediated toxicity induced by nanoparticles. We summarized and critically assessed adverse drug reactions of current clinically approved nanomedicines. Importantly, we show that physicochemical properties have great impact on nanoparticles interaction with cells, excretion route and kinetics, and subsequently on toxicity. We analyzed literature on adverse reactions of current nanomedicines and hypothesized that adverse reactions might be linked with lysosomal dysfunction caused by nanomedicines. Finally, from our analysis it becomes clear that it is unjustifiable to generalize safety and toxicity of nanoparticles, since different particles possess distinct toxicological properties. We propose that the biological mechanism of the disease progression and treatment should be central in the optimization of nanoparticle design.

Folic acid-decorated PEGylated magnetite nanoparticles as efficient drug carriers to tumor cells overexpressing folic acid receptor

The improved drug delivery systems (DDS) are needed for the targeted delivery of their therapeutic cargo (biologically active protein/peptide molecules, nucleic acids, vaccines, etc.) to diseased cells. Thus, we aimed to develop magnetite nanoparticles (Fe₃O₄), stabilized with polyethylene glycol (PEG) and decorated (surface-functionalized) with folic acid (FA) (Fe₃O₄@PEG@FA) to ensure targeted internalization in cells expressing the folic acid receptors (FR). The Fe₃O₄@PEG@FA nanoparticles were synthesized by co-precipitation in a one-pot methodology. Curcumin (Curc), a polyphenol with anti-tumoral activity, was loaded on the nanoparticles, and FA-targeted (Fe₃O₄@PEG@FA@Curc) and non-targeted (Fe₃O₄@PEG@Curc) systems were obtained. The internalization of Fe₃O₄@PEG@FA@Curc and Fe₃O₄@PEG@Curc nanoparticles was determined in two tumor cell lines, the FR-positive MCF-7 human breast carcinoma cell line and A549 human lung adenocarcinoma cell line, expressing a low level of FR. The results showed that MCF-7 cells internalize FA-functionalized nanoparticles to a greater extent than non-targeted ones and also than A549 cells. The competitive studies performed in the presence of FA in excess suggested that internalization is an FR-dependent process. The increased internalization of Fe₃O₄@PEG@FA@Curc nanoparticles in MCF-7 cells is correlated with increased cytotoxicity in this cell line compared to A549 cells. In conclusion, the FA-functionalized magnetic systems can ensure a better internalization of the nanoparticles and can be used to deliver various therapeutic agents, both in cancer treatment and also in the treatment of other inflammation-associated diseases such as rheumatoid arthritis, systemic lupus erythematosus, osteoarthritis, Crohn's disease or atherosclerosis.

Nanomaterial-Based Drug Delivery System Targeting Lymph Nodes

The lymphatic system plays an indispensable role in humoral balance, lipid metabolism, and immune regulation. The lymph nodes (LNs) are known as the primary sites of tumor metastasis and the metastatic LNs largely affected the prognosis of the patiens. A well-designed lymphatic-targeted system favors disease treatment as well as vaccination efficacy. In recent years, development of nanotechnologies and emerging biomaterials have gained increasing attention in developing lymph-node-targeted drug-delivery systems. By mimicking the endogenous macromolecules or lipid conjugates, lymph-node-targeted nanocarries hold potential for disease diagnosis and tumor therapy. This review gives an introduction to the physiological functions of LNs and the roles of LNs in diseases, followed by a review of typical lymph-node-targeted nanomaterial-based drug-delivery systems (e.g., liposomes, micelles, inorganic nanomaterials, hydrogel, and nanocapsules). Future perspectives and conclusions concerned with lymph-node-targeted drug-delivery systems are also provided.

Nanoparticles of cisplatin augment drug accumulations and inhibit multidrug resistance transporters in human glioblastoma cells

Background

Cisplatin (CSP) is a potent anticancer drug widely used in treating glioblastoma multiforme (GBM). However, CSP's clinical efficacy in GBM contrasted with low therapeutic ratio, toxicity, and multidrug resistance (MDR). Therefore, we have developed a system for the active targeting of cisplatin in GBM via cisplatin loaded polymeric nanoplatforms (CSP-NPs).

Methods

CSP-NPs were prepared by modified double emulsion and nanoprecipitation techniques. The physiochemical characterizations of CSP-NPs were performed using zeta sizer, scanning electron microscopy (SEM), drug release kinetics, and drug content analysis. Cytotoxicity, induction of apoptosis, and cell cycle-specific activity of CSP-NPs in human GBM cell lines were evaluated by MTT assay, fluorescent microscopy, and flow cytometry. Intracellular drug uptake was gauged by fluorescent imaging and flow cytometry. The potential of CSP-NPs to inhibit MDR transporters were assessed by flow cytometry-based drug efflux assays.

Results

CSP-NPs have smooth surface properties with discrete particle size with required zeta potential, polydispersity index, drug entrapment efficiency, and drug content. CSP-NPs has demonstrated an ‘initial burst effect’ followed by sustained drug release properties. CSP-NPs imparted dose and time-dependent cytotoxicity and triggered apoptosis in human GBM cells. Interestingly, CSP-NPs significantly increased uptake, internalization, and accumulations of anticancer drugs. Moreover, CSP-NPs significantly reversed the MDR transporters (ABCB1 and ABCG2) in human GBM cells.

Conclusion

The nanoparticulate system of cisplatin seems to has a promising potential for active targeting of cisplatin as an effective and specific therapeutic for human GBM, thus eliminating current chemotherapy's limitations.

Targeted polymeric nanoparticle for anthracycline delivery in hypoxia-induced drug resistance in metastatic breast cancer cells

Poly lactic-co-glycolic acid (PLGA) nanoparticles are intensively studied nanocarriers in drug delivery because of their biodegradability and biochemical characteristics. Polyethylene glycol (PEG) coating for nanocarriers gives them long circulation time in blood and makes them invisible to the reticuloendothelial system. Breast cancer cells have greater uptake of hyaluronic acid compared to normal cells as it binds to their overexpressed CD44 receptors. Since hypoxia plays an important role in cancer metastasis; we formulated PEG-PLGA nanoparticles coated with hyaluronic acid as targeted delivery system for doxorubicin (DOX) using nanoprecipitation method, and characterized them for chemical composition, size, surface charge, shape, and encapsulation efficiency. Then we tested them in vitro on hypoxia-optimized metastatic breast cancer cells. The nanoparticles were spherical with an average size of about 106 ± 53 nm, a negative surface charge (-15 ± 3 mV), and high encapsulation efficiency (73.3 ± 4.1%). In vitro investigation with hypoxia-elevated CD44 MDA-MB-231 cells showed that hyaluronic acid-targeted nanoparticles maintained their efficacy despite hypoxia-induced drug resistance unlike free DOX and nontargeted nanoparticles. In conclusion, this study revealed a simple third generation nanoparticle formulation for targeted treatment of hypoxia-induced drug resistance in breast cancer metastatic cells. Further, optimization is needed including In vivo efficacy and nanoparticle-specific pharmacokinetic studies.

Lipid, polymeric, inorganic-based drug delivery applications for platinum-based anticancer drugs

The three main FDA-approved platinum drugs in chemotherapy such as carboplatin, cisplatin, and oxaliplatin are extensively applied in cancer treatments. Although the clinical applications of platinum-based drugs are extremely effective, their toxicity profile restricts their extensive application. Therefore, recent studies focus on developing new platinum drug formulations, expanding the therapeutic aspect. In this sense, recent advances in the development of novel drug delivery carriers will help with the increase of drug stability and biodisponibility, concomitantly with the reduction of drug efflux and undesirable secondary toxic effects of platinum compounds. The present review describes the state of the art of platinum drugs with their biological effects, pre- and clinical studies, and novel drug delivery nanodevices based on lipids, polymers, and inorganic.

Co-Delivery of Curcumin and Cisplatin to Enhance Cytotoxicity of Cisplatin Using Lipid-Chitosan Hybrid Nanoparticles

Background

Lipid-polymer hybrid nanoparticles (LPHNP) are suitable for co-delivery of hydrophilic and lipophilic drugs. The structural advantages of polymers and biomimetic properties of lipids enable higher encapsulation of drugs and controlled release profile. Lipid-polymer hybrid nanoparticles have been prepared for co-delivery of curcumin and cisplatin for enhanced cytotoxicity against ovarian cancer.

Material and Methods

Chitosan, cisplatin, curcumin, Lipoid S75 were selected as structural components and ionic gelation method was used for preparation of LPHNPs. Nanoparticles were formed via ionic interaction of positively charged chitosan and negatively charged lipid.

Results

The optimized nanoparticles were of 225 nm with cationic charge. The encapsulation efficiency was greater than 80% with good drug loading. The drug release profile showed controlled release behavior of both curcumin and cisplatin simultaneously and the absence of burst release. The in vitro therapeutic efficacy and cellular association was evaluated using A2780 ovarian cell lines. To further investigate therapeutic efficacy, we developed 3D spheroids as tumor model to mimic the in vivo conditions. The cytotoxicity and uptake of co-loaded LPHNPs were evaluated on 3D spheroids and results indicated increased chemosensitization and enhanced therapeutic efficacy of co-loaded LPHNPs.

Conclusion

Lipid-polymer hybrid nanoparticles could be a suitable platform for co-delivery of curcumin and cisplatin for enhanced cytotoxic effect on ovarian cell lines.

Sensitization of cisplatin-resistant ovarian cancer cells by magnetite iron oxide nanoparticles: an in vitro study

Aim: To investigate potential of magnetite iron oxide nanoparticles (MION) to sensitize cisplatin-resistant ovarian cancer cells to cisplatin, which to the best of found knowledge has not been reported previously. Materials & methods: MION with a diameter of approximately 20 nm were synthesized, and characterized using Fourier transform infrared spectroscopy, powder x-ray diffraction and particle size analyzer. Results: The synthesized MION have increased reactive oxygen species levels and decreased glutathione levels in cisplatin-resistant ovarian cancer cells (OVCAR-3 and SKOV-3). Using MTT, capsase-3 activity and live/dead assays, capability of the synthesized MION to sensitize cisplatin-resistant ovarian cancer cells has been illustrated. Conclusion: Thus, for further investigations, the synthesized MION can be considered as a potent agent enabling much more effective cisplatin-based therapies for ovarian cancer.

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.

Prolonged Release and Functionality of Interleukin-10 Encapsulated within PLA-PEG Nanoparticles

Inflammation, as induced by the presence of cytokines and chemokines, is an integral part of chlamydial infections. The anti-inflammatory cytokine, interleukin (IL)-10, has been reported to efficiently suppress the secretion of inflammatory cytokines triggered by Chlamydia in mouse macrophages. Though IL-10 is employed in clinical applications, its therapeutic usage is limited due to its short half-life. Here, we document the successful encapsulation of IL-10 within the biodegradable polymeric nanoparticles of PLA-PEG (Poly (lactic acid)-Poly (ethylene glycol), to prolong its half-life. Our results show the encapsulated-IL-10 size (~238 nm), zeta potential (−14.2 mV), polydispersity index (0.256), encapsulation efficiency (~77%), and a prolonged slow release pattern up to 60 days. Temperature stability of encapsulated-IL-10 was favorable, demonstrating a heat capacity of up to 89 °C as shown by differential scanning calorimetry analysis. Encapsulated-IL-10 modulated the release of IL-6 and IL-12p40 in stimulated macrophages in a time- and concentration-dependent fashion, and differentially induced SOCS1 and SOCS3 as induced by chlamydial stimulants in macrophages. Our finding offers the tremendous potential for encapsulated-IL-10 not only for chlamydial inflammatory diseases but also biomedical therapeutic applications.

Chemistry Routes for Copolymer Synthesis Containing PEG for Targeting, Imaging, and Drug Delivery Purposes

Polyethylene glycol (PEG) is one of the most frequently used polymers for coating nanocarriers to enhance their biocompatibility, hydrophilicity, stability, and biodegradability. PEG is now considered to be among the best biocompatible polymers. It offers sterical hindrance against other nanoparticles and blood components such as opsonin, preventing their macrophage phagocytosis and resulting in a prolonged circulation time in blood stream, consequently a ‘stealth character’ in vivo. Therefore, PEG has a very promising future for the development of current therapeutics and biomedical applications. Moreover, the vast number of molecules that PEG can conjugate with might enhance its ability to have an optimistic perspective for the future. This review will present an update on the chemistry used in the modern conjugation methods for a variety of PEG conjugates, such methods include, but are not limited to, the synthesis of targeting PEG conjugates (i.e., Peptides, Folate, Biotin, Mannose etc.), imaging PEG conjugates (i.e., Coumarin, Near Infrared dyes etc.) and delivery PEG conjugates (i.e., doxorubicin, paclitaxel, and other hydrophobic low molecular weight drugs). Furthermore, the type of nanoparticles carrying those conjugates, along with their biomedical uses, will be briefly discussed.

Purging of malignant cell contamination prior to spermatogonia stem cell autotransplantation to preserve fertility: progress & prospects

PURPOSE OF REVIEW

This systematic review evaluates the state of the art in terms of strategies used to detect and remove contaminated malignant cells from testicular biopsy prior to spermatogonia stem cells (SSCs) autotransplantation to restore fertility.

RECENT FINDINGS

Several trials have been done in past two decades to determine the reliable methods of detecting and purging cancer cells prior to SSCs autotransplantation.

SUMMARY

The success in treating childhood cancer has dramatically increased over the past few decades. This leads to increasing demand for a method of fertility preservation for patients with pediatric cancer, as many cancer therapies can be gonadotoxic. Storing the SSCs prior to chemo- or radiation therapies and transplanting them back has been tested as a method of restoring fertility in rodents and nonhuman primate models. This has promise for restoring fertility in childhood cancer survivors. One of the major concerns is the possibility of malignant cell presence in testicular tissue biopsies that could re-introduce cancer to the patient after SSCs autotransplantation. Non-solid cancers - especially hematologic malignancies - have the risk of being transplanted back into patients after SSCs cryopreservation even if they were only present in small number in the stored testicular tissue biopsy.

Cisplatin-loaded PLGA nanoparticles for HER2 targeted ovarian cancer therapy

The conventional treatment (cytoreduction combined with cisplatin/carboplatin and taxane drugs) of ovarian cancer has a high rate of failure and recurrence despite a favorable initial response. This lack of success is usually attributed to the development of multidrug resistance mechanisms by cancer cells and avoidance of the anti-growth effects of monoclonal targeted therapeutic antibodies. The disease, like other cancers, is characterized by the overexpression of molecular markers, including HER2 receptors. Preclinical and clinical studies with trastuzumab, a HER2-targeted therapeutic antibody, reveal a low improvement of the outcomes of HER2 positive ovarian cancer patients. Therefore, here, we propose a cisplatin-loaded, HER2 targeted poly(lactic-co-glycolic) nanoplatform, a system capable to escape the drug-efflux effect and to take advantage of the overexpressed HER2 receptors, using them as docks for targeted chemotherapy. The NP/trastuzumab ratio was determined after fluorescein labeling of antibodies and quantification of fluorescence in NPs. The system was also characterized in terms of size, zeta potential, drug release kinetics, cytotoxicity and cellular internalization in the epithelial ovarian cancer cell line SKOV-3, and compared with the HER2 negative breast cancer cell line HCC70. Our results show an increased cytotoxicity of NPs as compared to free cisplatin, and moreover, an enhanced internalization and cytotoxicity due to the bionfunctionalization of NPs with the monoclonal antibody.

Elimination of mouse tumor cells from neonate spermatogonial cells utilizing cisplatin-entrapped folic acid-conjugated poly(lactic-co-glycolic acid) nanoparticles in vitro

Background

Some male survivors of childhood cancer are suffering from azoospermia. In addition, spermatogonial stem cells (SSCs) are necessary for the improvement of spermatogenesis subsequent to exposure to cytotoxic agents such as cisplatin.

Objective

The aim of this study was to evaluate the anticancer activity of cisplatin-loaded folic acid-conjugated poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) on mouse malignant cell line (EL4) and SSCs in vitro.

Methods

SSCs were co-cultured with mouse malignant cell line (EL4) cells and divided into four culture groups: 1) control (cells were co-cultured in the culture medium), 2) co-cultured cells were treated with cisplatin (10 μg/mL), 3) co-cultured cells were treated with cisplatin-loaded folic acid-conjugated PLGA NPs, and 4) co-cultures were treated with folic acid-conjugated PLGA for 48 hours. The NPs were prepared, characterized, and targeted with folate. In vitro release characteristics, loading efficiency, and scanning electron microscopy and transmission electron microscopy images were studied. Cancer cells were assayed after treatment using flow cytometry and TUNEL assay. The co-cultures of SSCs and EL4 cells were injected into seminiferous tubules of the testes after treating with cis-diaminedichloroplatinum/PLGA NPs.

Results

The mean diameter of PLGA NPs ranged between 150 and 250 nm. The number of TUNEL-positive cells increased, and the expression of Bax and caspase-3 were upregulated in EL4 cells in Group 4 compared with Group 2. There was no pathological tumor in testes after transplantation with treated co-cultured cells.

Conclusion

The PLGA NPs appeared to act as a promising carrier for cisplatin administration, which was consistent with a higher activation of apoptosis than free drug.

Advances in microfluidics for lipid nanoparticles and extracellular vesicles and applications in drug delivery systems

Lipid-based nanobiomaterials as liposomes and lipid nanoparticles (LNPs) are the most widely used nanocarriers for drug delivery systems (DDSs). Extracellular vesicles (EVs) and exosomes are also expected to be applied as DDS nanocarriers. The performance of nanomedicines relies on their components such as lipids, targeting ligands, encapsulated DNA, encapsulated RNA, and drugs. Recently, the importance of the nanocarrier sizes smaller than 100nm is attracting attention as a means to improve nanomedicine performance. Microfluidics and lab-on-a chip technologies make it possible to produce size-controlled LNPs by a simple continuous flow process and to separate EVs from blood samples by using a surface marker, ligand, or electric charge or by making a mass or particle size discrimination. Here, we overview recent advances in microfluidic devices and techniques for liposomes, LNPs, and EVs and their applications for DDSs.

A Potential Bone-Targeting Hypotoxic Platinum(II) Complex with an Unusual Cytostatic Mechanism toward Osteosarcoma Cells

Osteosarcoma (OS) is the most common primary pediatric bone tumor lethal to children and adolescents. Chemotherapeutic agents such as cisplatin are not effective for OS because of their poor accessibility to this cancer and severe systemic toxicity. In this study, a lipophilic platinum(II) complex bearing a bisphosphonate bone-targeting moiety, cis-[PtL(NH₃)₂Cl]NO₃ {BPP; L = tetraethyl [2-(pyridin-2-yl)ethane-1,1-diyl]bisphosphonate}, was prepared and characterized by NMR, electrospray ionization mass spectrometry, and single-crystal X-ray crystallography. The cytotoxicity of BPP toward OS cell lines U2OS and MG-63 was tested by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. BPP exhibits moderate inhibition against U2OS cells through a mechanism involving both DNA binding and a mevalonate pathway. The acute toxicity of BPP to mice is 7-fold lower than that of cisplatin. The relative low systemic toxicity may result from the steric hindrance of the ligand, which blocks BPP approaching the bases of DNA. The results suggest that incorporating bisphosphonates into a platinum complex not only enhances its bone-targeting property but also minimizes its reactivity toward DNA and thereby lowers the systematic toxicity of the complex. The diminished cytotoxicity of BPP could be compensated for by increasing the therapeutic dose with marginal harm. This strategy provides a new possibility for overcoming the ineffectiveness and systemic toxicity of platinum drugs in the treatment of OS.

Understanding the formation mechanism of lipid nanoparticles in microfluidic devices with chaotic micromixers

Lipid nanoparticles (LNPs) or liposomes are the most widely used drug carriers for nanomedicines. The size of LNPs is one of the essential factors affecting drug delivery efficiency and therapeutic efficiency. Here, we demonstrated the effect of lipid concentration and mixing performance on the LNP size using microfluidic devices with the aim of understanding the LNP formation mechanism and controlling the LNP size precisely. We fabricated microfluidic devices with different depths, 11 μm and 31 μm, of their chaotic micromixer structures. According to the LNP formation behavior results, by using a low concentration of the lipid solution and the microfluidic device equipped with the 31 μm chaotic mixer structures, we were able to produce the smallest-sized LNPs yet with a narrow particle size distribution. We also evaluated the mixing rate of the microfluidic devices using a laser scanning confocal microscopy and we estimated the critical ethanol concentration for controlling the LNP size. The critical ethanol concentration range was estimated to be 60–80% ethanol. Ten nanometer-sized tuning of LNPs was achieved for the optimum residence time at the critical concentration using the microfluidic devices with chaotic mixer structures. The residence times at the critical concentration necessary to control the LNP size were 10, 15–25, and 50 ms time-scales for 30, 40, and 50 nm-sized LNPs, respectively. Finally, we proposed the LNP formation mechanism based on the determined LNP formation behavior and the critical ethanol concentration. The precise size-controlled LNPs produced by the microfluidic devices are expected to become carriers for next generation nanomedicines and they will lead to new and effective approaches for cancer treatment.

A novel approach to fabricate dye-encapsulated polymeric micro- and nanoparticles by thin film dewetting technique

A new method is reported for fabrication of polymeric micro- and nanoparticles from an intermediate patterned surface originated by dewetting of a polymeric thin film. Poly (d, l-lactide-co-glycolide) or PLGA, a biocompatible polymer is used to develop a thin film over a clean glass substrate which dewets spontaneously in the micro-/nano-patterned surface of size range 50nm to 3.5µm. Since another water-soluble polymer, poly vinyl alcohol (PVA) is coated on the same glass substrate before PLGA thin film formation, developed micro-/nano-patterns are easily extracted in water in the form of micro- and nanoparticle mixture of size range 50nm to 3.0µm. This simplified method is also used to effectively encapsulate a dye molecule, rhodamine B inside the PLGA micro-/nanoparticles. The developed dye-encapsulated nanoparticles, PLGA-rhodamine are separated from the mixture and tested for in-vitro delivery application of external molecules inside human lung cancer cells. For the first time, the use of thin film dewetting technique is reported as a potential route for the synthesis of polymeric micro-/nanoparticles and effective encapsulation of external species therein.

Carbohydrate-based amphiphilic nano delivery systems for cancer therapy

Nanoparticles (NPs) are novel drug delivery systems that have been attracting more and more attention in recent years, and have been used for the treatment of cancer, infection, inflammation and other diseases. Among the numerous classes of materials employed for constructing NPs, organic polymers are outstanding due to the flexibility of design and synthesis and the ease of modification and functionalization. In particular, NP based amphiphilic polymers make a great contribution to the delivery of poorly-water soluble drugs. For example, natural, biocompatible and biodegradable products like polysaccharides are widely used as building blocks for the preparation of such drug delivery vehicles. This review will detail carbohydrate based amphiphilic polymeric systems for cancer therapy. Specifically, it focuses on the nature of the polymer employed for the preparation of targeted nanocarriers, the synthetic methods, as well as strategies for the application and evaluation of biological activity. Applications of the amphiphilic polymer systems include drug delivery, gene delivery, photosensitizer delivery, diagnostic imaging and specific ligand-assisted cellular uptake. As a result, a thorough understanding of the relationship between chemical structure and biological properties facilitate the optimal design and rational clinical application of the resulting carbohydrate based nano delivery systems for cancer therapy.

Two-Dimensional Fluorescence Difference Spectroscopy to Characterize Nanoparticles and their Interactions

Two dimensional fluorescence difference spectroscopy (2D FDS) detects nanoparticle interactions following surface functionalization and biomolecule loading by generating a spectral signature of the fluorescent intensity per excitation and emission wavelengths. Comparing metal oxide nanoparticles revealed a unique spectral signature per material composition. 2D FDS showed to be sensitive to changes in surface properties between ZnO NPs synthesized by different methods. ZnO NP loaded with glycol chitosan, polyacrylic acid (PAA), or methoxy polyethylene glycol (mPEG) exhibited a distinct spectral signature shift. ZnO NP loaded with Torula Yeast RNA (TYRNA)(640 nm), polyinosinic: polycytidylic acid (pIC)(680 nm), or splice switching oligonucleotide (SSO)(650 nm) each revealed a shift in emission. Ras-Binding domain (RBD) at three concentrations (25, 37.5, 50 μg/mL) showed that fluorescent intensity was inversely related to the concentration of protein loaded. These data support 2D FDS as a novel technique in identifying nanoparticles and their surface interactions as a quality assurance tool.

Hypericin-bearing magnetic iron oxide nanoparticles for selective drug delivery in photodynamic therapy

Combining the concept of magnetic drug targeting and photodynamic therapy is a promising approach for the treatment of cancer. A high selectivity as well as significant fewer side effects can be achieved by this method, since the therapeutic treatment only takes place in the area where accumulation of the particles by an external electromagnet and radiation by a laser system overlap. In this article, a novel hypericin-bearing drug delivery system has been developed by synthesis of superparamagnetic iron oxide nanoparticles (SPIONs) with a hypericin-linked functionalized dextran coating. For that, sterically stabilized dextran-coated SPIONs were produced by coprecipitation and crosslinking with epichlorohydrin to enhance stability. Carboxymethylation of the dextran shell provided a functionalized platform for linking hypericin via glutaraldehyde. Particle sizes obtained by dynamic light scattering were in a range of 55-85 nm, whereas investigation of single magnetite or maghemite particle diameter was performed by transmission electron microscopy and X-ray diffraction and resulted in approximately 4.5-5.0 nm. Surface chemistry of those particles was evaluated by Fourier transform infrared spectroscopy and ζ potential measurements, indicating successful functionalization and dispersal stabilization due to a mixture of steric and electrostatic repulsion. Flow cytometry revealed no toxicity of pure nanoparticles as well as hypericin without exposure to light on Jurkat T-cells, whereas the combination of hypericin, alone or loaded on particles, with light-induced cell death in a concentration and exposure time-dependent manner due to the generation of reactive oxygen species. In conclusion, the combination of SPIONs' targeting abilities with hypericin's phototoxic properties represents a promising approach for merging magnetic drug targeting with photodynamic therapy for the treatment of cancer.

Polymeric nanoparticles: the future of nanomedicine

Polymeric nanoparticles (NPs) are one of the most studied organic strategies for nanomedicine. Intense interest lies in the potential of polymeric NPs to revolutionize modern medicine. To determine the ideal nanosystem for more effective and distinctly targeted delivery of therapeutic applications, particle size, morphology, material choice, and processing techniques are all research areas of interest. Utilizations of polymeric NPs include drug delivery techniques such as conjugation and entrapment of drugs, prodrugs, stimuli-responsive systems, imaging modalities, and theranostics. Cancer, neurodegenerative disorders, and cardiovascular diseases are fields impacted by NP technologies that push scientific boundaries to the leading edge of transformative advances for nanomedicine.

The chemotherapeutic potential of doxorubicin-loaded PEG-b-PLGA nanopolymersomes in mouse breast cancer model

Vesicles of mPEG-PLGA block copolymer were developed to deliver a therapeutic quantity of doxorubicin (DOX) for breast cancer treatment. The DOX-loaded nanoparticles (NPs) were prepared by the pH-gradient method and then evaluated in terms of morphology, size, DOX encapsulation efficiency and in vitro drug release mechanism. The PEG-PLGA nanopolymersomes were 134±1.2nm spherical NPs with a narrow size distribution (PDI=0.121). DOX was entrapped in mPEG-PLGA nanopolymersomes with an encapsulation efficiency and a loading content of 91.25±4.27% and 7.3±0.34%, respectively. The DOX-loaded nanopolymersomes were found to be stable, demonstrating no significant change in particle size and encapsulation efficiency (EE%) during the 6-month storage period of the lyophilized powder at 4°C. The nanopolymersomes sustained the release of DOX. In cytotoxicity studies of 4T1 cell line samples, free DOX showed a higher cytotoxicity (IC50=1.76μg/mL) than did DOX-loaded nanopolymersomes (15.82μg/mL) in vitro. In order to evaluate the antitumor efficacy and biodistribution of DOX-loaded nanopolymersomes, murine breast tumors were established on the BALB/c mice, and in vivo studies were performed. The obtained results demonstrated that the prepared drug delivery system was highly effective against a murine breast cancer tumor model and successfully accumulated in the tumor site through an enhanced permeation and retention mechanism. In vivo studies also proved that DOX-loaded nanopolymersomes are stable in blood circulation and could be considered a promising and effective DOX delivery system for breast cancer treatment.

Evaluation of drug loading, pharmacokinetic behavior, and toxicity of a cisplatin-containing hydrogel nanoparticle

Cisplatin is a cytotoxic drug used as a first-line therapy for a wide variety of cancers. However, significant renal and neurological toxicities limit its clinical use. It has been documented that drug toxicities can be mitigated through nanoparticle formulation, while simultaneously increasing tumor accumulation through the enhanced permeation and retention effect. Circulation persistence is a key characteristic for exploiting this effect, and to that end we have developed long-circulating, PEGylated, polymeric hydrogels using the Particle Replication In Non-wetting Templates (PRINT®) platform and complexed cisplatin into the particles (PRINT-Platin). Sustained release was demonstrated, and drug loading correlated to surface PEG density. A PEG Mushroom conformation showed the best compromise between particle pharmacokinetic (PK) parameters and drug loading (16wt.%). While the PK profile of PEG Brush was superior, the loading was poor (2wt.%). Conversely, the drug loading in non-PEGylated particles was better (20wt.%), but the PK was not desirable. We also showed comparable cytotoxicity to cisplatin in several cancer cell lines (non-small cell lung, A549; ovarian, SKOV-3; breast, MDA-MB-468) and a higher MTD in mice (10mg/kg versus 5mg/kg). The pharmacokinetic profiles of drug in plasma, tumor, and kidney indicate improved exposure in the blood and tumor accumulation, with concurrent renal protection, when cisplatin was formulated in a nanoparticle. PK parameters were markedly improved: a 16.4-times higher area-under-the-curve (AUC), a reduction in clearance (CL) by a factor of 11.2, and a 4.20-times increase in the volume of distribution (Vd). Additionally, non-small cell lung and ovarian tumor AUC was at least twice that of cisplatin in both models. These findings suggest the potential for PRINT-Platin to improve efficacy and reduce toxicity compared to current cisplatin therapies.

Polymeric nanoparticles for targeted treatment in oncology: current insights

Chemotherapy, a major strategy for cancer treatment, lacks the specificity to localize the cancer therapeutics in the tumor site, thereby affecting normal healthy tissues and advocating toxic adverse effects. Nanotechnological intervention has greatly revolutionized the therapy of cancer by surmounting the current limitations in conventional chemotherapy, which include undesirable biodistribution, cancer cell drug resistance, and severe systemic side effects. Nanoparticles (NPs) achieve preferential accumulation in the tumor site by virtue of their passive and ligand-based targeting mechanisms. Polymer-based nanomedicine, an arena that entails the use of polymeric NPs, polymer micelles, dendrimers, polymersomes, polyplexes, polymer–lipid hybrid systems, and polymer–drug/protein conjugates for improvement in efficacy of cancer therapeutics, has been widely explored. The broad scope for chemically modifying the polymer into desired construct makes it a versatile delivery system. Several polymer-based therapeutic NPs have been approved for clinical use. This review provides an insight into the advances in polymer-based targeted nanocarriers with focus on therapeutic aspects in the field of oncology.

Dendrimer-PLGA based multifunctional immuno-nanocomposite mediated synchronous and tumor selective delivery of siRNA and cisplatin: potential in treatment of hepatocellular carcinoma

The in-house synthesized PLK-1 siRNA and cisplatin loaded innovative dendrimer-PLGA immuno-nanocomposite bears the capacity of delivering both the cargos simultaneously to the same liver cancer cell in a targeted manner.

Development and characterization of magnetic iron oxide nanoparticles with a cisplatin-bearing polymer coating for targeted drug delivery

A highly selective and efficient cancer therapy can be achieved using magnetically directed superparamagnetic iron oxide nanoparticles (SPIONs) bearing a sufficient amount of the therapeutic agent. In this project, SPIONs with a dextran and cisplatin-bearing hyaluronic acid coating were successfully synthesized as a novel cisplatin drug delivery system. Transmission electron microscopy images as well as X-ray diffraction analysis showed that the individual magnetite particles were around 4.5 nm in size and monocrystalline. The small crystallite sizes led to the superparamagnetic behavior of the particles, which was exemplified in their magnetization curves, acquired using superconducting quantum interference device measurements. Hyaluronic acid was bound to the initially dextran-coated SPIONs by esterification. The resulting amide bond linkage was verified using Fourier transform infrared spectroscopy. The additional polymer layer increased the vehicle size from 22 nm to 56 nm, with a hyaluronic acid to dextran to magnetite weight ratio of 51:29:20. A maximum payload of 330 μg cisplatin/mL nanoparticle suspension was achieved, thus the particle size was further increased to around 77 nm with a zeta potential of -45 mV. No signs of particle precipitation were observed over a period of at least 8 weeks. Analysis of drug-release kinetics using the dialysis tube method revealed that these were driven by inverse ligand substitution and diffusion through the polymer shell as well as enzymatic degradation of hyaluronic acid. The biological activity of the particles was investigated in a nonadherent Jurkat cell line using flow cytometry. Further, cell viability and proliferation was examined in an adherent PC-3 cell line using xCELLigence analysis. Both tests demonstrated that particles without cisplatin were biocompatible with these cells, whereas particles with the drug induced apoptosis in a dose-dependent manner, with secondary necrosis after prolonged incubation. In conclusion, combination of dextran-coated SPIONs with hyaluronic acid and cisplatin represents a promising approach for magnetic drug targeting in the treatment of cancer.

Chitosan coated polylactic acid nanoparticle-mediated combinatorial delivery of cisplatin and siRNA/Plasmid DNA chemosensitizes cisplatin-resistant human ovarian cancer cells

Development of resistance toward anticancer drugs results in ineffective therapy leading to increased mortality. Therefore, overriding resistance and restoring sensitivity to anticancer drugs will improve treatment efficacy and reduce mortality. While numerous mechanisms for drug resistance in cancer have previously been demonstrated, recent studies implicate a role for proteasome and the autophagy regulatory protein P62/SQSTM1 (P62) in contributing to drug resistance. Specifically, reduction in the expression of the β5 subunit of the proteasome and/or enhanced P62 protein expression is known to contribute to cancer drug resistance such as cisplatin (CDDP) in ovarian cancer cells. Therefore, we hypothesized that restoration of β5 expression and/or suppression of P62 protein expression in CDDP-resistant ovarian cancer cells will lead to restoration of sensitivity to CDDP and enhanced cell killing. To test our hypothesis we developed a biodegradable multifunctional nanoparticle (MNP) system that codelivered P62siRNA, β5 plasmid DNA, and CDDP and tested its efficacy in CDDP resistant 2008/C13 ovarian cancer cells. MNP consisted of CDDP loaded polylactic acid nanoparticle as inner core and cationic chitosan (CS) consisting of ionically linked P62siRNA (siP62) and/or β5 expressing plasmid DNA (pβ5) as the outer layer. The MNPs were spherical in shape with a hydrodynamic diameter in the range of 280-350 nm, and demonstrated encapsulation efficiencies of 82% and 78.5% for CDDP and siRNA respectively. MNPs efficiently protected the siRNA and showed superior serum stability compared to naked siRNA as measured by gel retardation and spectrophotometry assays. The MNPs successfully delivered siP62 and pβ5 to cause P62 knockdown and restoration of β5 expression in 2008/C13 cells. Combined delivery of siP62, pβ5, and CDDP using the MNPs resulted in a marked reduction in the IC50 value of CDDP in 2008/C13 cells from 125 ± 1.3 μM to 98 ± 0.6 μM (P < 0.05; 21.6% reduction) when compared to the reduction in the IC50 of CDDP observed in cells that had only siP62 delivered (IC50 = 106 ± 1.1 μM; P < 0.05; 15.2% reduction) or pβ5 delivered (IC50 = 115 ± 2.8 μM; 8% reduction) via MNPs. Finally, our studies showed that the CDDP resistance index in 2008/C13 cells was reduced from 4.62 for free CDDP to 3.62 for MNP treatment. In conclusion our study results demonstrated the efficacy of our MNP in overcoming CDDP resistance in ovarian cancer cells.

Polymer nanoparticles for drug and small silencing RNA delivery to treat cancers of different phenotypes

Advances in nanotechnology have provided powerful and efficient tools in the development of cancer diagnosis and therapy. There are numerous nanocarriers that are currently approved for clinical use in cancer therapy. In recent years, biodegradable polymer nanoparticles have attracted a considerable attention for their ability to function as a possible carrier for target-specific delivery of various drugs, genes, proteins, peptides, vaccines, and other biomolecules in humans without much toxicity. This review will specifically focus on the recent advances in polymer-based nanocarriers for various drugs and small silencing RNA's loading and delivery to treat different types of cancer.

Critical evaluation of biodegradable polymers used in nanodrugs

Use of biodegradable polymers for biomedical applications has increased in recent decades due to their biocompatibility, biodegradability, flexibility, and minimal side effects. Applications of these materials include creation of skin, blood vessels, cartilage scaffolds, and nanosystems for drug delivery. These biodegradable polymeric nanoparticles enhance properties such as bioavailability and stability, and provide controlled release of bioactive compounds. This review evaluates the classification, synthesis, degradation mechanisms, and biological applications of the biodegradable polymers currently being studied as drug delivery carriers. In addition, the use of nanosystems to solve current drug delivery problems are reviewed.

Cisplatin-incorporated nanoparticles of poly(acrylic acid-co-methyl methacrylate) copolymer

Background

Although cisplatin is extensively used in the clinical field, its intrinsic toxicity limits its clinical use. We investigated nanoparticle formations of poly(acrylic acid-co-methyl methacrylate) (PAA-MMA) incorporating cisplatin and their antitumor activity in vitro and in vivo.

Methods

Cisplatin-incorporated nanoparticles were prepared through the ion-complex formation between acrylic acid and cisplatin. The anticancer activity of cisplatin-incorporated nanoparticles was assessed with CT26 colorectal carcinoma cells.

Results

Cisplatin-incorporated nanoparticles have small particle sizes of less than 200 nm with spherical shapes. Drug content was increased according to the increase of the feeding amount of cisplatin and acrylic acid content in the copolymer. The higher acrylic acid content in the copolymer induced increase of particle size and decrease of zeta potential. Cisplatin-incorporated nanoparticles showed a similar growth-inhibitory effect against CT26 tumor cells in vitro. However, cisplatin-incorporated nanoparticles showed improved antitumor activity against an animal tumor xenograft model.

Conclusion

We suggest that PAA-MMA nanoparticles incorporating cisplatin are promising carriers for an antitumor drug-delivery system.

Detoxifying antitumoral drugs via nanoconjugation: the case of gold nanoparticles and cisplatin

Nanoparticles (NPs) have emerged as a potential tool to improve cancer treatment. Among the proposed uses in imaging and therapy, their use as a drug delivery scaffold has been extensively highlighted. However, there are still some controversial points which need a deeper understanding before clinical application can occur. Here the use of gold nanoparticles (AuNPs) to detoxify the antitumoral agent cisplatin, linked to a nanoparticle via a pH-sensitive coordination bond for endosomal release, is presented. The NP conjugate design has important effects on pharmacokinetics, conjugate evolution and biodistribution and results in an absence of observed toxicity. Besides, AuNPs present unique opportunities as drug delivery scaffolds due to their size and surface tunability. Here we show that cisplatin-induced toxicity is clearly reduced without affecting the therapeutic benefits in mice models. The NPs not only act as carriers, but also protect the drug from deactivation by plasma proteins until conjugates are internalized in cells and cisplatin is released. Additionally, the possibility to track the drug (Pt) and vehicle (Au) separately as a function of organ and time enables a better understanding of how nanocarriers are processed by the organism.