Co-delivery of cisplatin and paclitaxel by folic acid conjugated amphiphilic PEG-PLGA copolymer nanoparticles for the treatment of non-small lung cancer

Anti-Colon Cancer Activity of Copper-Doped Folate Carbon Dots/MnO2 Complexes Based on Oxygenation and Immune-Enhancing Effects

In clinical practice, the treatment of colon cancer is faced with the dilemma of metastasis and recurrence, which is related to immunosuppression and hypoxia. Immune checkpoint blockade (ICB) is a negative regulatory pathway of immunity. Immune checkpoint blockade (ICB) is an important immunotherapy method. However, inadequate immunogenicity reduces the overall response rate of ICB. In this study, a tumor microenvironment-responsive nanomedicine (Cu-FACD@MnO2@FA) was prepared to increase host immune response and increase intracellular oxygen levels. Cu-FACD@MnO2@FA preferentially enriched at the tumor site, combined with the immune checkpoint inhibitor alpha PD-L1, induced sufficient immunogenicity to treat colon cancer. Immunofluorescence detection of tumor cells and tissues showed that the expression of hypoxa-inducing factor 1α was significantly down-regulated after treatment and the expression of immunoactivity-related proteins was significantly changed. In vivo treatment in a bilateral tumor mouse model showed complete ablation of the primary tumor and efficient inhibition of the distal tumor. In this study, for the first time, the oxygenation effects of MnO2-coated Cu-doped carbon dots and chemodynamic therapy and a strategy of combining with immuno-blocking therapy were used for treating colon cancer.

Immunogenic Cell Death Induction and Oxygenation by Multifunctional Hollow Silica/Copper-Doped Carbon Dots

The metastasis and recurrence of cancer are related to immunosuppression and hypoxia in the tumor microenvironment. Activating immune activity and improving the hypoxic environment face essential challenges. This paper reports on a multifunctional nanomaterial, HSCCMBC, that induces immunogenic cell death through powerful photodynamic therapy/chemodynamic therapy synergistic antitumor effects. The tumor microenvironment changed from the immunosuppressive type to immune type, activated the immune activity of the system, decomposed hydrogen peroxide to generate oxygen based on Fenton-like reaction, and effectively increased the level of intracellular O2 with the assistance of 3-bromopyruvate, a cell respiratory inhibitor. The structure and composition of HSCCMBC were characterized by transmission electron microscopy, X-ray photoelectron spectroscopy, X-ray diffraction, infrared spectroscopy, etc. Oxygen probe RDPP was used to investigate the oxygen level inside and outside the cell, and hydroxyl radical probe tetramethylbenzidine was used to investigate the Fenton-like reaction ability. The immunofluorescence method investigated the expression of various immune markers and hypoxia-inducing factors in vitro and in vivo after treatment. In vitro and in vivo experiments indicate that HSCCMBC is an excellent antitumor agent and is expected to be a candidate drug for antitumor immunotherapy.

Pulmonary inhalation for disease treatment: Basic research and clinical translations

Pulmonary drug delivery has the advantages of being rapid, efficient, and well-targeted, with few systemic side effects. In addition, it is non-invasive and has good patient compliance, making it a highly promising drug delivery mode. However, there have been limited studies on drug delivery via pulmonary inhalation compared with oral and intravenous modes. This paper summarizes the basic research and clinical translation of pulmonary inhalation drug delivery for the treatment of diseases and provides insights into the latest advances in pulmonary drug delivery. The paper discusses the processing methods for pulmonary drug delivery, drug carriers (with a focus on various types of nanoparticles), delivery devices, and applications in pulmonary diseases and treatment of systemic diseases (e.g., COVID-19, inhaled vaccines, diagnosis of the diseases, and diabetes mellitus) with an updated summary of recent research advances. Furthermore, this paper describes the applications and recent progress in pulmonary drug delivery for lung diseases and expands the use of pulmonary drugs for other systemic diseases.

The diverse effects of cisplatin on tumor microenvironment: Insights and challenges for the delivery of cisplatin by nanoparticles

Cisplatin is a well-known platinum-based chemotherapy medication that is widely utilized for some malignancies. Despite the direct cytotoxic consequences of cisplatin on tumor cells, studies in the recent decade have revealed that cisplatin can also affect different cells and their secretions in the tumor microenvironment (TME). Cisplatin has complex impacts on the TME, which may contribute to its anti-tumor activity or drug resistance mechanisms. These regulatory effects of cisplatin play a paramount function in tumor growth, invasion, and metastasis. This paper aims to review the diverse impacts of cisplatin and nanoparticles loaded with cisplatin on cancer cells and also non-cancerous cells in TME. The impacts of cisplatin on immune cells, tumor stroma, cancer cells, and also hypoxia will be discussed in the current review. Furthermore, we emphasize the challenges and prospects of using cisplatin in combination with other adjuvants and therapeutic modalities that target TME. We also discuss the potential synergistic effects of cisplatin with immune checkpoint inhibitors (ICIs) and other agents with anticancer potentials such as polyphenols and photosensitizers. Furthermore, the potential of nanoparticles for targeting TME and better delivery of cisplatin into tumors will be discussed.

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.

A novel quinoline derivative, DFIQ, sensitizes NSCLC cells to ferroptosis by promoting oxidative stress accompanied by autophagic dysfunction and mitochondrial damage

BACKGROUND

The development of nonapoptotic programmed cell death inducers as anticancer agents has emerged as a cancer therapy field. Ferroptosis, ferrous ion-driven programmed cell death that is induced by redox imbalance and dysfunctional reactive oxygen species (ROS) clearance, is triggered during sorafenib and PD-1/PD-L1 immunotherapy. DFIQ, a quinoline derivative, promotes apoptosis by disrupting autophagic flux and promoting ROS accumulation. Our pilot experiments suggest that DFIQ participates in ferroptosis sensitization. Thus, in this study, we aimed to reveal the mechanisms of DFIQ in ferroptosis sensitization and evaluate the clinical potential of DFIQ.

METHODS

We treated the non-small cell lung cancer (NSCLC) cell lines H1299, A549, and H460 with the ferroptosis inducer (FI) DFIQ and analyzed viability, protein expression, ROS generation, and fluorescence staining at different time points. Colocalization analysis was performed with ImageJ.

RESULTS

DFIQ sensitized cells to FIs such as erastin and RSL3, resulting in a decrease in IC50 of at least 0.5-fold. Measurement of ROS accumulation to explore the underlying mechanism indicated that DFIQ and FIs treatment promoted ROS accumulation and SOD1/SOD2 switching. Mitochondria, known ROS sources, produced high ROS levels during DFIQ/FI treatment. RSL3 treatment promoted mitochondrial damage and mitophagy, an autophagy-associated mitochondrial recycling system, and cotreatment with DFIQ induced accumulation of mitochondrial proteins, which indicated disruption of mitophagic flux. Thus, autophagic flux was measured in cells cotreated with DFIQ. DFIQ treatment was found to disrupt autophagic flux, leading to accumulation of damaged mitochondria and eventually inducing ferroptosis. Furthermore, the influence of DFIQ on the effects of clinical FIs, such as sorafenib, was evaluated, and DFIQ was discovered to sensitize NSCLC cells to sorafenib and promote ferroptosis.

CONCLUSIONS

This study indicates that DFIQ not only promotes NSCLC apoptosis but also sensitizes cells to ferroptosis by disrupting autophagic flux, leading to accumulation of dysfunctional mitochondria and thus to ferroptosis. Ferroptosis is a novel therapeutic target in cancer therapy. DFIQ shows the potential to enhance the effects of FIs in NSCLC and act as a potential therapeutic adjuvant in ferroptosis-mediated therapy.

Organic disulfide-modified folate carbon dots for tumor-targeted synergistic chemodynamic/photodynamic therapy

Carbon dots (CDs) have great potential for cancer diagnosis and treatment. Photodynamic therapy and chemodynamic therapy are promising treatments mediated by reactive oxygen species (ROS), which have the advantages of being minimally invasive, having no multi-drug resistance, and having no systemic toxic side effects. However, the tumor microenvironment (TME) and poor targetability often reduce the therapeutic effect. In this work, we have successfully prepared folate-based carbon dots (FCP-CDs) from folic acid (FA), citric acid (CA), and polyethyleneimine (PEI) for tumor-targeting. The surface of FCP-CDs was modified using organic disulfide, 3,3'-dithiodipropionic acid (DTPA), and a photosensitizer (PS) pyropheophorbide-a (PPa) to form a tumor microenvironment-responsive nanoplatform, FCP-CDs@DTPA@PPa (named FCPPD), for synergistic cancer therapy. The results showed that FCPPD effectively preserved the tumor target specificity of folic acid and the photodynamic therapeutic (PDT) activity of PPa, and could provide additional chemodynamic therapeutic (CDT) function by reacting with hydrogen peroxide (H₂O₂) to generate ˙OH. The introduction of DTPA, which contains disulfide bonds, endows FCPPD with an excellent ability to deplete glutathione (GSH) in tumors via intracellular redox reactions, amplifying intracellular oxidative strain and enhancing ROS-based therapeutic effects. Systematic in vitro and in vivo studies under various conditions have shown that the obtained FCPPD nanoparticles have good biocompatibility and could be a promising therapeutic agent for imaging-guided PDT/CDT combination therapy.

Folate-Mediated Paclitaxel Nanodelivery Systems: A Comprehensive Review

Paclitaxel (PTX) is used as a viable cancer medication in the chemotherapy of breast, ovarian, lung, bladder, neck, head, and esophageal tumors. The focus of this review is to survey various folate-targeting PTX-loaded nanopreparations in both research and clinical applications. There are diverse nanopreparations, including liposomes, micelles, polymeric nanopreparations, lipid nanopreparations, lipoprotein nanocarriers, and other inorganic nanopreparations for folate-associated PTX tumor targeting. Here, the folate targeting PTX-loaded nanopreparations, which have promising results in the constructive treatment of cancer by reducing toxic side-effects and/or improving effectiveness, was mainly reviewed.

Nanoparticle drug delivery systems for synergistic delivery of tumor therapy

Nanoparticle drug delivery systems have proved anti-tumor effects; however, they are not widely used in tumor therapy due to insufficient ability to target specific sites, multidrug resistance to anti-tumor drugs, and the high toxicity of the drugs. With the development of RNAi technology, nucleic acids have been delivered to target sites to replace or correct defective genes or knock down specific genes. Also, synergistic therapeutic effects can be achieved for combined drug delivery, which is more effective for overcoming multidrug resistance of cancer cells. These combination therapies achieve better therapeutic effects than delivering nucleic acids or chemotherapeutic drugs alone, so the scope of combined drug delivery has also been expanded to three aspects: drug-drug, drug-gene, and gene-gene. This review summarizes the recent advances of nanocarriers to co-delivery agents, including i) the characterization and preparation of nanocarriers, such as lipid-based nanocarriers, polymer nanocarriers, and inorganic delivery carriers; ii) the advantages and disadvantages of synergistic delivery approaches; iii) the effectual delivery cases that are applied in the synergistic delivery systems; and iv) future perspectives in the design of nanoparticle drug delivery systems to co-deliver therapeutic agents.

Nanocarriers containing platinum compounds for combination chemotherapy

Platinum compounds-based drugs are used widely in the clinic for the treatment of many types of cancer. However, serious undesirable side effects and intrinsic or acquired resistance limit their successful clinic use. Nanocarrier-based combination chemotherapy is considered to be an effective strategy to resolve these challenges. This review introduces the recent advance in nanocarriers containing platinum compounds for combination cancer chemotherapy, including liposomes, polymer nanoparticles, polymer micelles, mesoporous silica nanoparticles, carbon nanohors, polymer-caged nanobins, carbon nanotube, nanostructured lipid carriers, solid lipid nanoparticles, and multilayered fiber mats in detail.

Progress in the drug encapsulation of poly(lactic-co-glycolic acid) and folate-decorated poly(ethylene glycol)-poly(lactic-co-glycolic acid) conjugates for selective cancer treatment

Poly(lactic-co-glycolic acid) (PLGA) is a US Food and Drug Administration (FDA)-approved polymer used in humans in the forms of resorbable sutures, drug carriers, and bone regeneration materials. Recently, PLGA-based conjugates have been extensively investigated for cancer, which is the second leading cause of death globally. This article presents an account of the literature on PLGA-based conjugates, focusing on their chemistries, biological activity, and functions as targeted drug carriers or sustained drug controllers for common cancers (e.g., breast, prostate, and lung cancers). The preparation and drug encapsulation of PLGA nanoparticles and folate-decorated poly(ethylene glycol)-poly(lactic-co-glycolic acid) (FA-PEG-PLGA) conjugates are discussed, along with several representative examples. Particularly, the reactions used for preparing drug-conjugated PLGA and FA-PEG-PLGA are emphasized, with the associated chemistries involved in the formation of structures and their biocompatibility with internal organs. This review provides a deeper understanding of the constituents and interactions of PLGA-conjugated materials to ensure successful conjugation in PLGA material design and the subsequent biomedical applications.

Modulating Nanoparticle Size to Understand Factors Affecting Hemostatic Efficacy and Maximize Survival in a Lethal Inferior Vena Cava Injury Model

Intravenous nanoparticle hemostats offer a potentially attractive approach to promote hemostasis, in particular for inaccessible wounds such as noncompressible torso hemorrhage (NCTH). In this work, particle size was tuned over a range of <100-500 nm, and its effect on nanoparticle-platelet interactions was systematically assessed using in vitro and in vivo experiments. Smaller particles bound a larger percentage of platelets per mass of particle delivered, while larger particles resulted in higher particle accumulation on a surface of platelets and collagen. Intermediate particles led to the greatest platelet content in platelet-nanoparticle aggregates, indicating that they may be able to recruit more platelets to the wound. In biodistribution studies, smaller and intermediate nanoparticles exhibited longer circulation lifetimes, while larger nanoparticles resulted in higher pulmonary accumulation. The particles were then challenged in a 2 h lethal inferior vena cava (IVC) puncture model, where intermediate nanoparticles significantly increased both survival and injury-specific targeting relative to saline and unfunctionalized particle controls. An increase in survival in the second hour was likewise observed in the smaller nanoparticles relative to saline controls, though no significant increase in survival was observed in the larger nanoparticle size. In conjunction with prior in vitro and in vivo experiments, these results suggest that platelet content in aggregates and extended nanoparticle circulation lifetimes are instrumental to enhancing hemostasis. Ultimately, this study elucidates the role of particle size in platelet-particle interactions, which can be a useful tool for engineering the performance of particulate hemostats and improving the design of these materials.

Application of Nanoparticles in the Treatment of Lung Cancer With Emphasis on Receptors

Lung cancer is one of the malignant tumors that has seen the most rapid growth in terms of morbidity and mortality in recent years, posing the biggest threat to people’s health and lives. In recent years, the nano-drug loading system has made significant progress in the detection, diagnosis, and treatment of lung cancer. Nanomaterials are used to specifically target tumor tissue to minimize therapeutic adverse effects and increase bioavailability. It is achieved primarily through two mechanisms: passive targeting, which entails the use of enhanced penetration and retention (EPR) effect, and active targeting, which entails the loading recognition ligands for tumor marker molecules onto nanomaterials. However, it has been demonstrated that the EPR effect is effective in rodents but not in humans. Taking this into consideration, researchers paid significant attention to the active targeting nano-drug loading system. Additionally, it has been demonstrated to have a higher affinity and specificity for tumor cells. In this review, it describes the development of research into active targeted nano-drug delivery systems for lung cancer treatment from the receptors’ or targets’ perspective. We anticipate that this study will help biomedical researchers use nanoparticles (NPs) to treat lung cancer by providing more and novel drug delivery strategies or solid ligands.

Unraveling the Effect of Breast Cancer Patients' Plasma on the Targeting Ability of Folic Acid-Modified Chitosan Nanoparticles

The formation of protein corona (PC) around nanoparticles (NPs) has been reported inside biological conditions. This effect can alter delivery capacity toward the targeted tissues. Here, we synthesized folic acid-modified chitosan NPs (FA-CS NPs) using different concentrations of folic acid (5, 10, and 20%). FA-CS NPs were exposed to plasmas of breast cancer patients and healthy donors to evaluate the possibility of PC formation. We also monitored uptake efficiency in in vitro conditions after incubation with human breast cancer cell line MDA-MB-231 and monocyte/macrophage-like Raw264.7 cells. Data showed that the formation of PC around FA-CS NPs can change physicochemical properties coincided with the rise in NP size and negative surface charge. SDS-PAGE electrophoresis revealed differences in the type and content rate of plasma proteins attached to NP surface in a personalized manner. Based on MTT data, the formation of PC around NPs did not exert cytotoxic effects on MDA-MB-231 cells while this phenomenon reduced uptake rate. Fluorescence imaging and flow cytometry analyses revealed reduced cellular internalization rate in NPs exposed to patients' plasma compared to the control group. In contrast to breast MDA-MB-231 cells, Raw264.7 cells efficiently adsorbed the bare and PC-coated NPs from both sources, indicating the involvement of ligand-receptor-dependent and independent cellular engulfment. These data showed that the PC formed on the FA-CS NPs is entirely different in breast cancer patients and healthy counterparts. PC derived from patients' plasma almost abolishes the targeting efficiency of FA-CS NPs even in different mechanisms, while this behavior was not shown in the control group. Surprisingly, Raw264.7 cells strongly adsorbed the PC-coated NPs, especially when these particles were in the presence of patients' sera. It is strongly suggested that the formation of PC around can affect delivering capacity of FA-CS NPs to cancer cells. It seems that the PC-coated FA-CS NPs can be used as an efficient delivery strategy for the transfer of specific biomolecules in immune system disorders.

Mesoporous silica nanoparticles for pulmonary drug delivery

Over the last years, respiratory diseases represent a clinical concern, being included among the leading causes of death in the world due to the lack of effective lung therapies, mainly ascribed to the pulmonary barriers affecting the delivery of drugs to the lungs. In this way, nanomedicine has arisen as a promising approach to overcome the limitations of current therapies for pulmonary diseases. The use of nanoparticles allows enhancing drug bioavailability at the target site while minimizing undesired side effects. Despite different approaches have been developed for pulmonary delivery of drugs, including the use of polymers, lipid-based nanoparticles, and inorganic nanoparticles, more efforts are required to achieve effective pulmonary drug delivery. This review provides an overview of the clinical challenges in main lung diseases, as well as highlighted the role of nanomedicine in achieving efficient pulmonary drug delivery. Drug delivery into the lungs is a complex process limited by the anatomical, physiological and immunological barriers of the respiratory system. We discuss how nanomedicine can be useful to overcome these pulmonary barriers and give insights for the rational design of future nanoparticles for enhancing lung treatments. We also attempt herein to display more in detail the potential of mesoporous silica nanoparticles (MSNs) as promising nanocarrier for pulmonary drug delivery by providing a comprehensive overview of their application in lung delivery to date while discussing the use of these particles for the treatment of respiratory diseases.

The role of a drug-loaded poly (lactic co-glycolic acid) (PLGA) copolymer stent in the treatment of ovarian cancer

Objectives: Cisplatin (CDDP) is a widely used and effective basic chemotherapeutic drug for the treatment of a variety of tumors, including ovarian cancer. However, adverse side effects and acquired drug resistance are observed in the clinical application of CDDP. Identifying a mode of administration that can alleviate side effects and reduce drug resistance has become a promising strategy to solve this problem.

Methods: In this study, 3D printing technology was used to prepare a CDDP-poly (lactic-co-glycolic acid) (CDDP-PLGA) polymer compound stent, and its physicochemical properties and cytotoxicity were evaluated both in vitro and in vivo.

Results: The CDDP-PLGA stent had a significant effect on cell proliferation and apoptosis and clearly decreased the size of subcutaneous tumors in nude mice, whereas the systemic side effects were mild compared with those of intraperitoneal CDDP injection. Compared with the control group, CDDP-PLGA significantly increased the mRNA and protein levels of p-glycoprotein (P < 0.01; P < 0.01) and decreased vascular endothelial growth factor mRNA (P < 0.05) and protein levels (P < 0.01), however, CDDP-PLGA significantly decreased the mRNA and protein levels of p-glycoprotein (P < 0.01; P < 0.01) and vascular endothelial growth factor (P < 0.01; P < 0.01), which are associated with chemoresistance, in subcutaneous tumor tissue. Immunohistochemistry assay results revealed that, in the CDDP-PLGA group, the staining of the proliferation-related genes Ki67 and PCNA were lightly, and the apoptosis-related gene caspase-3 stained deeply.

Conclusions: PLGA biomaterials loaded with CDDP, as compared with the same amount of free CDDP, showed good efficacy in terms of cytotoxicity, as evidenced by changes in apoptosis. Continuous local CDDP release can decrease the systemic side effects of this drug and the occurrence of drug resistance and angiogenesis, and improve the therapeutic effect. This new approach may be an effective strategy for the local treatment of epithelial ovarian cancer.

Pulmonary Delivery of Docetaxel and Celecoxib by PLGA Porous Microparticles for Their Synergistic Effects Against Lung Cancer

BACKGROUND

using a combination of chemotherapeutic agents with novel drug delivery platforms to enhance the anticancer efficacy of the drug and minimizing the side effects, is very imperative for lung cancer treatments.

OBJECTIVE

The aim of the present study was to develop, characterize, and optimize porous poly (D, L-lactic-co-glycolic acid) (PLGA) microparticles for simultaneous delivery of docetaxel (DTX) and celecoxib (CXB) through the pulmonary route for lung cancer.

METHODS

Drug-loaded porous microparticles were prepared by an emulsion solvent evaporation method. The impact of various processing and formulation variables including PLGA amount, dichloromethane volume, homogenization speed, polyvinyl alcohol volume and concentration were assessed on entrapment efficiency, mean release time, particle size, mass median aerodynamic diameter, fine particle fraction and geometric standard deviation using a two-level factorial design. An optimized formulation was prepared and evaluated in terms of size and morphology using a scanning electron microscope.

RESULTS

FTIR, DSC, and XRD analysis confirmed drug entrapment and revealed no drug-polymer chemical interaction. Cytotoxicity of DTX along with CXB against A549 cells was significantly enhanced compared to DTX and CXB alone and the combination of DTX and CXB showed the greatest synergistic effect at a 1/500 ratio.

CONCLUSION

In conclusion, the results of the present study suggest that encapsulation of DTX and CXB in porous PLGA microspheres with desirable features are feasible and their pulmonary co-administration would be a promising strategy for the effective and less toxic treatment of various lung cancers.

Ligand decorated biodegradable nanomedicine in the treatment of cancer

Cancer is one of the major global health problems, responsible for the second-highest number of deaths. The genetic and epigenetic changes in the oncogenes or tumor suppressor genes alter the regulatory pathways leading to its onset and progression. Conventional methods are used in appropriate combinations for the treatment. Surgery effectively treats localized tumors; however, it fails to treat metastatic tumors, leading to a spread in other organs, causing a high recurrence rate and death. Among the different strategies, the nanocarriers-based approach is highly sought for, but its nonspecific delivery can cause a profound side effect on healthy cells. Targeted nanomedicine has the advantage of targeting cancer cells specifically by interacting with the receptors overexpressed on their surface, overcoming its non-specificity to target healthy cells. Nanocarriers prepared from biodegradable and biocompatible materials are decorated with different ligands by encapsulating therapeutic or diagnostic agents or both to target cancer cells overexpressing the receptors. Scientists are now utilizing a theranostic approach to simultaneously evaluate nanocarrier bio-distribution and its effect on the treatment regime. Herein, we have summarized the recent 5-year efforts in the development of the ligands decorated biodegradable nanocarriers, as a targeted nanomedicine approach, which has been highly promising in the treatment of cancer.

Single- versus Dual-Targeted Nanoparticles with Folic Acid and Biotin for Anticancer Drug Delivery

Cancer is one of the major causes of death worldwide and its treatment remains very challenging. The effectiveness of cancer therapy significantly depends upon tumour-specific delivery of the drug. Nanoparticle drug delivery systems have been developed to avoid the side effects of the conventional chemotherapy. However, according to the most recent recommendations, future nanomedicine should be focused mainly on active targeting of nanocarriers based on ligand-receptor recognition, which may show better efficacy than passive targeting in human cancer therapy. Nevertheless, the efficacy of single-ligand nanomedicines is still limited due to the complexity of the tumour microenvironment. Thus, the NPs are improved toward an additional functionality, e.g., pH-sensitivity (advanced single-targeted NPs). Moreover, dual-targeted nanoparticles which contain two different types of targeting agents on the same drug delivery system are developed. The advanced single-targeted NPs and dual-targeted nanocarriers present superior properties related to cell selectivity, cellular uptake and cytotoxicity toward cancer cells than conventional drug, non-targeted systems and single-targeted systems without additional functionality. Folic acid and biotin are used as targeting ligands for cancer chemotherapy, since they are available, inexpensive, nontoxic, nonimmunogenic and easy to modify. These ligands are used in both, single- and dual-targeted systems although the latter are still a novel approach. This review presents the recent achievements in the development of single- or dual-targeted nanoparticles for anticancer drug delivery.

Co-delivery Systems of Multiple Drugs Using Nanotechnology for Future Cancer Therapy

Cancer treatments have improved significantly during the last decade but are not yet satisfactory. Combination therapy is often administered to improve efficacy and safety. Drug delivery systems can also improve efficacy and safety. To control the spatiotemporal distribution of drugs, nanotechnology involving liposomes, solid lipid nanoparticles, and polymeric micelles has been developed. Co-delivery systems of multiple drugs are a promising approach to combat cancer. Synergistic effects and reduced side effects are expected from the use of co-delivery systems. In this review, we summarize various co-delivery systems for multiple drugs, including small-molecule drugs, nucleic acids, genes, and proteins. Co-delivery of drugs with different properties is relatively difficult, but some researchers have succeeded in developing such co-delivery systems. Environment-responsive carrier designs can control the release of cargos. Although their preparation is more complicated than that of mono-delivery systems, co-delivery systems can simplify clinical procedures and improve patient QOL.

Role of non-coding RNAs in modulating the response of cancer cells to paclitaxel treatment

Paclitaxel is a chemotherapeutic substance that is administered for treatment of an extensive spectrum of human malignancies. In spite of its potent short-term effects against tumor cells, resistance to paclitaxel occurs in a number of patients precluding its long-term application in these patients. Non-coding RNAs have been shown to influence response of cancer cells to this chemotherapeutic agent via different mechanisms. Mechanistically, these transcripts regulate expression of several genes particularly those being involved in the apoptotic processes. Lots of in vivo and in vitro assays have demonstrated the efficacy of oligonucleotide-mediated microRNAs (miRNA)/ long non-coding RNAs (lncRNA) silencing in enhancement of response of cancer cells to paclitaxel. Therefore, targeted therapies against non-coding RNAs have been suggested as applicable modalities for combatting resistance to this agent. In the present review, we provide a summary of studies which assessed the role of miRNAs and lncRNAs in conferring resistance to paclitaxel.

Enhanced Anti-Cancer Effect of Folate-Conjugated Olaparib Nanoparticles Combined with Radiotherapy in Cervical Carcinoma

BACKGROUND

Radiotherapy (RT), one of the main treatments for cervical cancer, has tremendous potential for improvement in the efficacy. Poly (ADP-ribose) polymerase (PARP) is a key enzyme in the repair of DNA strand breaks (DSB). Olaparib (Ola) is a PARP inhibitor that is involved in preventing the release of PARP from RT-induced damaged DNA to potentiate the effect of RT. Although the basic mechanism of Ola's radiosensitization is well known, the radiosensitization mechanism of its nanomedicine is still unclear. In addition, the lack of tumor tissue targeting is a major obstacle for the clinical success of Ola.

MATERIALS AND METHODS

In this study, we developed folate-conjugated active targeting olaparib nanoparticles (ATO) and investigated the anti-tumor effect of ATO combined with radiotherapy (RT) in nude mice using cervical cancer xenograft models. We used folate (FA)-conjugated poly (ε-caprolactone)-poly (ethyleneglycol)-poly (e-caprolactone) (PCEC) copolymer to prepare ATO via emulsification/solvent diffusion. Further, we evaluated ATO particle size, potential, encapsulation efficiency, and in vitro release characteristics, and evaluated the shape of ATO via transmission electron microscopy (TEM). We then performed MTT and cell uptake assays to detect cytotoxicity and targeting uptake in vitro. We investigated the anti-tumor properties of ATO in vivo by apoptosis test, 18 F-FDG PET/CT, and immunohistochemical analysis. Finally, the xenografted tumor in nude mice was subjected to RT and/or ATO treatment.

RESULTS

The results confirmed that ATO in combination with RT significantly inhibited tumor growth and prolonged survival time of tumor-bearing mice. This may be related to the inhibition of tumor proliferation and DNA damage repair and induction of cell apoptosis in vivo.

CONCLUSION

The ATO developed in this study may represent a novel formulation for olaparib delivery and have promising potential for treating tumors with an over-expression of folate receptors.

ROP and ATRP fabricated redox sensitive micelles based on PCL-SS-PMAA diblock copolymers to co-deliver PTX and CDDP for lung cancer therapy

Combining dual drugs in one vehicle to cancer cells offers spatiotemporal localization of drug at the site of action, leading to synergistic therapeutic effects and reduced side effects. To improve pH/redox responsiveness to the tumor microenvironments for cancer therapy, a pH/redox-responsive micelle based on poly(ε-caprolactone)-SS-poly(methacrylic acid) (PCL-SS-PMAA) diblock copolymer was fabricated for dual drug delivery. The PCL-SS-PMAA was formulated into a core-shell micelle (PSPm) in an aqueous solution. The critical micelle concentration (CMC) values of PSPm were 7.94 × 10^-3 mg mL^-1 at pH 5.0 and 1.00 × 10^-2 mg mL^-1 at pH 7.4. The hydrodynamic diameters of PSPm were within 210-270 nm, depending on pH values. Changes in morphology and size of PSPm were clearly observed before and after exposure to a reducing agent. Paclitaxel (PTX) was encapsulated into the core and cisplatin (CDDP) was chelated on the shell of PSPm, with both PTX and CDDP being efficiently released from PSPm in the presence of a reducing agent in an acid condition. MTT and annexin V/propidium iodide dual staining results demonstrated that co-loading of CDDP and PTX into PSPm had a synergistic effect in killing lung cancer cells and exerted superior antitumor activity over the combination of single drug-loaded PSPm or the combination of free-CDDP and free-PTX at equivalent drug amounts. Hence, encapsulating the dual drugs into PSPm exhibits a synergistic effect for potential lung cancer therapy.

Evaluation of tissue-clearing techniques for intraorgan imaging of distribution of polymeric nanoparticles as drug carriers

OBJECTIVE

The development of drug delivery systems using nanocarriers requires intraorgan imaging techniques for evaluating the distribution of nanocarriers. In this study, we evaluated the tissue-clearing techniques for the imaging of polymeric nanoparticles, a nanocarrier, in the liver used as a model of pigment-rich organ in mice.

SIGNIFICANCE

The intraorgan imaging method of polymeric nanoparticles was examined without sectioning of organ samples for evaluating the delivery efficiency in preclinical studies.

METHODS

DiI-loaded polymeric nanoparticles and fluorescence-tagged tomato lectin for fluorescence labeling of liver general structures were intravenously administered to mice. Tissue-clearing treatment of the mouse liver was performed using Clear^T2, ScaleSQ(0), clearing agent comprising fructose, urea, and glycerol for imaging (FUnGI), clear unobstructed brain/body imaging cocktails and computational analysis (CUBIC), and modified CUBIC techniques. Intraorgan fluorescence imaging in the liver was performed by confocal laser microscopy.

RESULTS

Clear^T2 treatment exhibited insufficient clearing capability in the mouse liver. Although CUBIC treatment exhibited the best clearing capability, the CUBIC caused DiI leakage. ScaleSQ(0), FUnGI, and modified CUBIC treatments exhibited better clearing capability than Clear^T2 technique while preserving the DiI. In the fluorescence imaging, the CUBIC and modified CUBIC exhibited deeper visualization than with the ScaleSQ(0) and FUnGI; however, the CUBIC led to a change in DiI distribution. The modified CUBIC enabled the deepest visualization while preserving the distribution of DiI.

CONCLUSION

The intraorgan imaging method was established using modified CUBIC technique by the intravenous administration of fluorescence-tagged tomato lectin for evaluating the distribution of polymeric nanoparticles in mouse pigment-rich organs.

Use of Anticancer Platinum Compounds in Combination Therapies and Challenges in Drug Delivery

As one of the leading and most important metal-based drugs, platinum-based pharmaceuticals are widely used in the treatment of solid malignancies. Despite significant side effects and acquired drug resistance have limited their clinical applications, platinum has shown strong inhibitory effects for a wide assortment of tumors. Drug delivery systems using emerging technologies such as liposomes, dendrimers, polymers, nanotubes and other nanocompositions, all show promise for the safe delivery of platinum-based compounds. Due to the specificity of nano-formulations; unwanted side-effects and drug resistance can be largely averted. In addition, combinational therapy has been shown to be an effective way to improve the efficacy of platinum based anti-tumor drugs. This review first introduces drug delivery systems used for platinum and combinational therapeutic delivery. Then we highlight some of the recent advances in the field of drug delivery for combinational therapy; specifically progress in leveraging the cytotoxic nature of platinum-based drugs, the combinational effect of other drugs with platinum, while evaluating the drug targeting, side effect reducing and sitespecific nature of nanotechnology-based delivery platforms.

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

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

Natural compounds as potential adjuvants to cancer therapy: Preclinical evidence

Traditional chemotherapy is being considered due to hindrances caused by systemic toxicity. Currently, the administration of multiple chemotherapeutic drugs with different biochemical/molecular targets, known as combination chemotherapy, has attained numerous benefits like efficacy enhancement and amelioration of adverse effects that has been broadly applied to various cancer types. Additionally, seeking natural-based alternatives with less toxicity has become more important. Experimental evidence suggests that herbal extracts such as Solanum nigrum and Claviceps purpurea and isolated herbal compounds (e.g., curcumin, resveratrol, and matairesinol) combined with antitumoral drugs have the potential to attenuate resistance against cancer therapy and to exert chemoprotective actions. Plant products are not free of risks: Herb adverse effects, including herb-drug interactions, should be carefully considered. LINKED ARTICLES: This article is part of a themed section on The Pharmacology of Nutraceuticals. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v177.6/issuetoc.

Improved Therapeutic Effect of Puerarin-Encapsulated PEG-PLGA Nanoparticle on an In Vitro Cerebral Infarction Model

This study was to explore the therapeutic effect and mechanism of puerarin (PUE) combined with PEGylated nanoparticles on a rat cerebral infarction cell model. In this context, PEG-PLGA/PUE nanoparticles were prepared by the thin-film hydration method, and the toxicity of PEG-PLGA/PUE nanoparticles to brain capillary endothelial cell (BCEC) was detected by MTT. The BCEC/TF cell model was obtained by induction of BCEC cells with TNF-α. The BCEC/TF cell model was identified by immunofluorescence; the protein expression was detected by western blotting; the expression level of miR-424 in cells was measured by RT-qPCR; the targeting relationship between miR-424 and PDCD4 was confirmed by dual-luciferase reporter assay. We found that PEG-PLGA/PUE nanoparticles prepared by the thin-film hydration method had uniform particle size, regular shape, and good stability and were not toxic to cells. The vWF was widely expressed in the cytoplasm in BCECs. The BCEC/TF cell model was obtained after TNF-α treatment, and tissue factor (TF) was widely expressed on the cell membrane of BCEC/TF cells. Furthermore, it was observed that the PEG-PLGA/PUE nanoparticles showed better therapeutic effect on the BCEC/TF cell model than PUE. PEG-PLGA/PUE nanoparticles and PUE inhibited the expression of PDCD4 protein by increasing the expression of miR-424 in BCEC/TF cells. In summary, the therapeutic effect of PEG-PLGA/PUE nanoparticles on the in vitro cell model of cerebral infarction is better than that of PUE. Moreover, PEG-PLGA/PUE inhibits the expression of PDCD4 protein by lowering the expression level of miR-424 in cells, thereby reducing the hazard of cerebral infarction.

Dual-targeting liposome modified by glutamic hexapeptide and folic acid for bone metastatic breast cancer

Bone is the most common organ affected by metastatic breast cancer. Targeting delivery of drugs to bone may not only enhance the treatment efficacy, but also reduce the quantity of drug administered. In order to increase the distribution of paclitaxel (PTX) in bone, herein, a novel bone metastasis-targeted glutamic hexapeptide-folic acid (Glu₆-FA) derivative was designed and synthesized as liposome ligand to deliver PTX to bone metastasis effectively. The liposomes were prepared by thin film hydration method and its particle size, zeta potential, encapsulation efficiency, release profile, stability, hemolysis were also characterized. What's more, the anti-tumor effects of PTX-Glu₆-FA-Lip were confirmed by the detection of cell cycle, migration, and further measurement of microtubule stabilization. In addition, the PTX-Glu₆-FA-Lip showed superior targeting ability in vitro and in vivo evaluation as compared to naked PTX, non-coated, singly-modified and co-modified by physical blending liposomes. All the results suggested that Glu₆-FA-modified liposome showed excellent targeting activity to metastatic bone cancer. These findings suggested that Glu₆-FA-Lip was a promising bone metastasis-targeting carrier for the delivery of PTX. This study may therefore be conducive to the field of bone-targeting drugs delivery.

Folate-conjugated nanovehicles: Strategies for cancer therapy

Cancer theranostics represents a strategy that aims at combining diagnosis with therapy through the simultaneous imaging and targeted delivery of therapeutics to cancer cells. Recently, the folate receptor alpha has emerged as an attractive theranostic target due to its overexpression in multiple solid tumors and its great functional versatility. In fact, it can be incorporated into folate-conjugated nano-systems for imaging and drug delivery. Hence, it can be used along the line of personalized clinical strategies as both an imaging tool and a delivery method ensuring the selective transport of treatments to tumor cells, thus highlighting its theranostic qualities. In this review, we will explore these theranostic characteristics in detail and assess their clinical potential. We will also discuss the technological advances that have allowed the design of sophisticated folate-based nanocarriers harboring various chemical properties and suited for the transport of various therapeutic agents.

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.

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

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

Advances in Carbon Nanotubes for Malignant Melanoma: A Chance for Treatment

Malignant melanoma is an aggressive skin cancer with limited therapeutic options. Cancer is the second largest cause of death in society and one of the most difficult diseases to treat. Advances in biotechnology have enabled the current use of nanotechnology via the application of nanomaterials, especially as drug delivery systems for the transportation of very small particles. In this context, carbon nanotubes, with a potential role in the diagnosis and treatment of melanoma, are still an emerging research field. Their properties have been extensively studied for the use of antineoplastics drugs, as well as for DNA and RNA interference for the treatment of cancer. However, the most important challenge in nanomedicine is to decrease the toxicity and increase the biocompatibility of the nanomaterials used to transport therapeutic molecules. In this sense, this article addresses the recent advances in the use of carbon nanotubes in melanoma therapy and highlights the opportunities and challenges in this area. The advances and challenges involving these topics are essential to the success of nanoconjugate systems, and studies improving the comprehension of these nanosystems contribute to the development of specific antitumor therapies.

Co-delivery of paclitaxel and cisplatin in poly(2-oxazoline) polymeric micelles: Implications for drug loading, release, pharmacokinetics and outcome of ovarian and breast cancer treatments

Concurrent delivery of multiple drugs using nanoformulations can improve outcomes of cancer treatments. Here we demonstrate that this approach can be used to improve the paclitaxel (PTX) and alkylated cisplatin prodrug combination therapy of ovarian and breast cancer. The drugs are co-loaded in the polymeric micelle system based on amphiphilic block copolymer poly(2-methyl-2-oxazoline-block-2-butyl-2-oxazoline-block-2-methyl-2-oxazoline) (P(MeOx-b-BuOx-b-MeOx). A broad range of drug mixing ratios and exceptionally high two-drug loading of over 50 wt.% drug in a stable micellar solution is demonstrated. The drugs co-loading in the micelles result in a slowed-down release to serum, improved pharmacokinetics and increased tumor distribution for both drugs. A superior anti-tumor activity of co-loaded PTX/CP drug micelles compared to single drug micelles or their mixture was demonstrated in cisplatin-resistant human ovarian carcinoma A2780/CisR xenograft tumor and multidrug resistant breast cancer LCC-6-MDR orthotopic tumor models. The improved tumor delivery of co-loaded drugs was related to decreased drug release rates as confirmed by simulation for micelle, serum and tumor compartments in a three-compartmental model. Overall, the results provide support for the use of PTX and cisplatin co-loaded micelles as a strategy for improved chemotherapy of ovarian and breast cancer and potential for the clinical translation.

Nanomedicines guided nanoimaging probes and nanotherapeutics for early detection of lung cancer and abolishing pulmonary metastasis: Critical appraisal of newer developments and challenges to clinical transition

Lung cancer (LC) is the second most prevalent type of cancer and primary cause of mortality among both men and women, worldwide. The most commonly employed diagnostic modalities for LC include chest X-ray (CXR), magnetic-resonance-imaging (MRI), computed tomography (CT-scan), and fused-positron-emitting-tomography-CT (PET-CT). Owing to several limitations associated with the use of conventional diagnostic tools such as radiation burden to the patient, misleading diagnosis ("missed lung cancer"), false staging and low sensitivity and resolution, contemporary diagnostic regimen needed to be employed for screening of LC. In recent decades, nanotechnology-guided interventions have been transpired as emerging nanoimaging probes for detection of LC at advanced stages, while producing signal amplification, better resolution for surface and deep tissue imaging, and enhanced translocation and biodistribution of imaging probes within the cancerous tissues. Besides enormous potential of nanoimaging probes, nanotechnology-based advancements have also been evidenced for superior efficacy for treatment of LC and abolishing pulmonary metastasis (PM). The success of nanotherapeutics is due to their ability to maximise translocation and biodistribution of anti-neoplastic agents into the tumor tissues, improve pharmacokinetic profiles of anti-metastatic agents, optimise target-specific drug delivery, and control release kinetics of encapsulated moieties in target tissues. This review aims to overview and critically discuss the superiority of nanoimaging probes and nanotherapeutics over conventional regimen for early detection of LC and abolishing PM. Current challenges to clinical transition of nanoimaging probes and therapeutic viability of nanotherapeutics for treatment for LC and PM have also been pondered.

Microneedle-Mediated Delivery of Lipid-Coated Cisplatin Nanoparticles for Efficient and Safe Cancer Therapy

Cisplatin is the first-line chemotherapeutic agent, but its systemic toxicity and side effects severely limit its clinical use. We report a microneedle technique to mediate the transdermal delivery of lipid-coated cisplatin nanoparticles (LCC-NPs) for efficient and safe cancer therapy. Cisplatin was encapsulated by tumor-targeting pH-responsive lipid nanoparticles with a high loading rate of 80%, and the encapsulation substantially increased the solubility of cisplatin and enhanced its antitumor efficiency in vitro. The LCC-NPs were embedded in dissolvable microneedles, and released from the microneedles after inserting into the skin. This enabled the nanoparticles to pass the stratum corneum for safe local delivery. An in vivo study with a xenograft tumor animal model demonstrated that microneedle arrays loaded with cisplatin nanoparticles significantly increased cytotoxicity and apoptosis in cancer cells with an apoptotic index of 58.6%, resulting in significantly reduced tumor volume and weight. Moreover, serum platinum, pulmonary toxicity, hepatotoxicity, and nephrotoxicity were not detected in vivo, indicating that this technique is biosafe. The cisplatin-nanoparticle microneedle system developed in this study may offer promising opportunities in cancer therapy for enhancing antitumor effects and reducing systemic toxicity and side effects.

Standardization of the infusion sequence of antineoplastic drugs used in the treatment of breast and colorectal cancers

The definition of antineoplastic administration sequences can help planning of therapeutic regimens in a more rational way, and thus optimize chemotherapy effects on patients, increasing efficacy and reducing toxic effects. In this way, this study aimed to evaluate the infusion order of antineoplastic agents of the main therapeutic protocols used in the treatment of colorectal and breast cancer which are used in a tertiary hospital, identifying possible interactions dependent on the infusion sequence. For the definition of protocols adopted in the hospital, medical prescriptions were used in the period of January to March 2016 and a literature review was conducted to search for studies assessing the sequence of administering the selected regimens. The databases used were SciELO, LILACS and MEDLINE, in addition to Micromedex Solutions® and UpToDate®. A total of 19 protocols were identified for antineoplastic therapy, 11 for colorectal cancer and 8 for breast cancer. The selected articles provided evidence for administration order of 19 protocols, and three protocols did no report relevance of infusion sequence. Sequence-dependent interactions were mainly related to toxicity, pharmacokinetics and efficacy of the drug combination. The definition of the infusion sequence has a great impact on the optimization of therapy, increasing efficacy and safety of the protocols containing combined antineoplastic therapies.

Targeted multifunctional redox-sensitive micelle co-delivery of DNA and doxorubicin for the treatment of breast cancer

Drug/gene co-delivery carriers are a promising strategy for cancer treatment. Thus, herein, T7-conjugated redox-sensitive amphiphilic polyethylene glycol-polyethyleneimine-poly(caprolactone)-SS-poly(caprolactone)-polyethyleneimine-polyethylene glycol (PEG-PEI-PCL-SS-PCL-PEG) (PPPT) is designed to realize the co-delivery of pORF-hTRAIL and DOX efficiently into tumor cells. PPPT is synthesized via the ring opening polymerization (ROP) of ε-caprolactone followed by Michael addition polymerization and atom transfer radical polymerization (ATRP) of the maleic imide group of MAL-PEG-NHS. The PPPT micelles present a spherical or ellipsoidal geometry with a mean diameter of approximately 100-120 nm. Meanwhile, they also exhibit a redox-responsive drug release profile in vitro. The blood compatibility and complement activation tests reveal that the PPPT micelles do not induce blood hemolysis, blood clotting, or complement activation. The T7-modified co-delivery system shows a higher cellular uptake efficiency than the unmodified co-delivery system in human breast cancer MCF-7 cells and is accumulated in tumor more efficiently in vivo. These results suggest that the T7-targeted codelivery system of DOX and pORF-hTRAIL is a combined delivery platform that can significantly improve the treatment of breast cancer.

PEGylated PLGA-based phase shift nanodroplets combined with focused ultrasound for blood brain barrier opening in rats

Previous studies have shown that focused ultrasound (FUS) combined with systematic administration of microbubbles (MBs) can open the blood brain barrier (BBB) locally, transiently and reversibly. However, because of the micro size diameters, MBs are restricted in the intravascular space and cannot extravasate into diseased sites through the opened BBB. In this study, we fabricated one kind of nanoscale droplets which consisted of encapsulated liquid perfluoropentane cores and poly (ethyleneglycol) - poly (lactide-co-glycolic acid) shells. The nanodroplets had the capacity to realize liquid to gas phase shift under FUS. Significant extravasation of Evan's blue appeared when acoustic pressure reached 1.0 MPa. Intracerebral hemorrhages and erythrocyte extravasations were observed when the pressure was increased to 1.5 MPa. Prolonged sonication duration could enhance the level of BBB opening and broaden the time window simultaneously. Furthermore, compared with MBs, the distribution of EB extravasation was firmly confined within narrow region in the center of focal zone, suggesting the site of FUS induced BBB opening could be controlled with high precision by this procedure. Our results show the feasibility of serving PEGylated PLGA-based phase shift nanodroplet as an effective alternative mediating agent for FUS induced BBB opening.

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

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

Lymph node metastases: importance of detection and treatment strategies

INTRODUCTION

Lymphatic vessels are the preferential route of most solid tumors to spread their metastases in the body. The onset of metastatic nests in draining lymph nodes (LNs) are a significant indicator of cancer progression and a dismaying sign of worsen staging. Therefore, the individuation and elimination of cancer cells within the lymphatic system (LS) are an important goal. Nevertheless, the targeting of the LS with traditional contrast agents and/or chemotherapeutics is difficult, due to its anatomical structure. For this reason, many studies on new lymphatic delivery systems have been carried out, both to improve lymphatic imaging and to selectively carry chemotherapeutics to LNs, reducing the exposure of healthy tissues to the cytotoxic substances. This is an overview of the present situation in the field of detection and treatment strategies of lymphatic metastases, taking into account the use of nano-drug delivery systems. Nanocarriers, thanks to their small size and other physicochemical characteristics, are suitable vectors for imaging and chemotherapy of the LS.

AREAS COVERED

The role of the LS in tumor progression and importance of treatment and imaging strategies of lymphatic metastases.

EXPERT OPINION

The nanoparticles are a promising approach for treatment and detection of lymphatic metastases. However further studies are necessary in order to evaluate their efficacy in human clinical application.

Nanocrystals of a new camptothecin derivative WCN-21 enhance its solubility and efficacy

WCN-21 is a new camptothecin derivative we synthesized and has desirable anti-tumor efficacy, but its aqueous solubility is very low and hurdles the further evaluation and development. In this study, we prepared nanocrystals of WCN-21 through a bottom-up approach to enhance its solubility and obtained WCN-21 nanorods (WND) and nanospheres (WNP). We investigated the crystallization of WND and WNP in different temperature and solvents and found that both temperature and solvents affect the crystal shapes and sizes. We prepared WND at 50°C and DMSO : H2O 1: 50 and WNP at 25°C and DMSO : H2O 1: 100 and found they were dispersed evenly in water with average hydrodynamic diameters 337 and 231 nm, respectively. WND and WNP increased the solubility of WCN-21 from extreme insolubility to more than 9 and 11 mM in H2O or PBS, respectively. In vitro studies showed that WND and WNP enhanced the uptake of WCN-21 in tumor cells by 3 and 9 folds, and increased cytotoxicity of WCN-21 in comparison with free WCN-21 by 5 and 6 folds, respectively. In xenograft tumor mice, intravenous injection of WND and WNP enhanced the accumulation of WCN-21 in tumor tissues and improved the anti-tumor efficacy. In addition, WND and WNP did not increase the toxicity of WCN-21 in mice. Therefore, nanocrystal is a robust tool to improve the solubility of insoluble drugs and holds a great potential in the application of drug development.

Developing an anticancer copper(II) pro-drug based on the nature of cancer cell and human serum albumin carrier IIA subdomain: mouse model of breast cancer

Human serum albumin (HSA)-based drug delivery systems are promising for improving delivery efficiency, anticancer activity and selectivity of anticancer agents. To rationally guide to design HSA carrier for anticancer metal agent, we built a breast mouse model on developing anti-cancer copper (Cu) pro-drug based on the nature of IIA subdomain of HSA carrier and cancer cells. Thus, we first synthesized a new Cu(II) compound derived from tridentate (E)-N'-(5-bromo-2-hydroxybenzylidene)benzohydrazide Schiff base ligand (HL) containing 2 potential leaving groups [indazole (Ind) and NO3-], namely, [Cu(L)(Ind)NO3]. Structural analysis of the HSA complex showed that Cu(L)(Ind)(NO3) could bind to the hydrophobic pocket of the HSA IIA subdomain. Lys199 and His242 coordinate with Cu2+ by replacing the indazole and NO3 ligands of [Cu(L)(Ind)NO3]. The release behavior of the Cu compound from the HSA complex is different at different pH levels. [Cu(L)(Ind)NO3] can enhance cytotoxicity by 2 times together with HSA specifically in cancer cells but has no such effect on normal cells in vitro. Importantly, our in vivo results showed that the HSA complex displayed increased selectivity and capacity to inhibit tumor growth and was less toxic than [Cu(L)(Ind)NO3] alone.

Combination of doxorubicin with harmine-loaded liposomes exerting synergistic antitumor efficacy

CONTEXT

Long-circulation (PEGLip), pH-sensitive (PEOzLip), and active targeted liposomes (PEG-TATLip)-loading doxorubicin (DOX) and harmine (HM) were prepared. Their physicochemical properties and antitumor effect were investigated.

OBJECTIVES

The aims of the present study were to evaluate synergistic antitumor efficacy.

MATERIALS AND METHODS

Liposomes were prepared by using thin-film dispersion, active drug-loading and target post-insertion method. Subsequently physiochemical properties including particle size distribution, zeta potential, entrapment efficiency (EE), drug-loading content and in-vitro release were determined. Besides, the in vitro cytotoxicity of free drugs and drug-loaded liposomes was explored by using a Sulforhodamine-B Staining assay and the combination index values (CI Value) were calculated. Finally, the cellular uptake experiments by MCF-7cells were carried out via flow cytometry.

RESULTS AND DISCUSSION

All liposomes enhanced the antitumor effect significantly compared to free drugs. Among liposomes, PEG-TATLip enhanced the antitumor effect significantly compared to others. DOX and HM had moderate synergism with CI Value 0.85 for free drugs, 0.81 for PEGLip, 0.72 for PEOzLip, and 0.84 for PEG-TATLip respectively when the weight ratio of two drugs was 1:2. Moreover, the similarity between DOX and HM such as physicochemical properties, in vitro release modes and in vitro uptake kinetics characteristics when they were in the same formulations proved it possible for them to be delivered together.

CONCLUSION

Active targeting liposomes were the most effective delivery system as compared with pH-sensitive and long circulation liposomes. Additionally, DOX and HM could be co-delivered in liposomes and they could play moderate synergism effect in antitumor efficacy.

Reduction-sensitive mixed micelles assembled from amphiphilic prodrugs for self-codelivery of DOX and DTX with synergistic cancer therapy

Clinically, codelivery of chemotherapeutics has been limited by poor water-solubility and severe systemic toxicity. In this work, we developed a new reduction-sensitive mixed micellar system for self-codelivery of doxorubicin (DOX) and docetaxel (DTX). Biodegradable methoxy poly(ethylene glycol)-poly(ε-caprolactone) (mPEG-PCL) was coupled with DOX and DTX by a reduction-sensitive disulfide bond, resulting in mPEG-PCL-SS-DOX and mPEG-PCL-SS-DTX, respectively. mPEG-PCL-SS-DOX was mixed with mPEG-PCL-SS-DTX at a mole ratio of 1:1 in water, forming a mixed micellar system. The mixed micelles had a diameter of 223.7nm and a low critical micelle concentration. Reductive-triggered drug release revealed a "smart" characteristic of the mixed micelles. A cellular uptake and cytotoxicity assay in vitro showed that the mixed micelles could efficiently accumulate in MCF-7 cells and suppress the growth of tumour cells. The proposed reduction-sensitive mixed micelles assembled from amphiphilic prodrugs can be used as a promising drug codelivery system for cancer therapy.

Critical Parameters for Particle-Based Pulmonary Delivery of Chemotherapeutics

Targeted delivery of chemotherapeutics through the respiratory system is a potential approach to improve drug accumulation in the lung tumor, while decreasing their negative side effects. However, elimination by the pulmonary clearance mechanisms, including the mucociliary transport system, and ingestion by the alveolar macrophages, rapid absorption into the blood, enzymatic degradation, and low control over the deposition rate and location remain the main complications for achieving an effective pulmonary drug delivery. Therefore, particle-based delivery systems have emerged to minimize pulmonary clearance mechanisms, enhance drug therapeutic efficacy, and control the release behavior. A successful implementation of a particle-based delivery system requires understanding the influential parameters in terms of drug carrier, inhalation technology, and health status of the patient's respiratory system. This review aims at investigating the parameters that significantly drive the clinical outcomes of various particle-based pulmonary delivery systems. This should aid clinicians in appropriate selection of a delivery system according to their clinical setting. It will also guide researchers in addressing the remaining challenges that need to be overcome to enhance the efficiency of current pulmonary delivery systems for aerosols.