A mechanistic study of enhanced doxorubicin uptake and retention in multidrug resistant breast cancer cells using a polymer-lipid hybrid nanoparticle system

Exploring the potential of P-glycoprotein inhibitors in the targeted delivery of anti-cancer drugs: A comprehensive review

Due to the high prevalence of cancer, progress in the management of cancer is the need of the hour. Most cancer patients develop chemotherapeutic drug resistance, and many remain insidious due to overexpression of Multidrug Resistance Protein 1 (MDR1), also known as Permeability-glycoprotein (P-gp) or ABCB1 transporter (ATP-binding cassette subfamily B member 1). P-gp, a transmembrane protein that protects vital organs from outside chemicals, expels medications from malignant cells. The blood-brain barrier (BBB), gastrointestinal tract (GIT), kidneys, liver, pancreas, and cancer cells overexpress P-gp on their apical surfaces, making treatment inefficient and resistant. Compounds that compete with anticancer medicines for transportation or directly inhibit P-gp may overcome biological barriers. Developing nanotechnology-based formulations may help overcome P-gp-mediated efflux and improve bioavailability and cell chemotherapeutic agent accumulation. Nanocarriers transport pharmaceuticals via receptor-mediated endocytosis, unlike passive diffusion, which bypasses ABCB1. Anticancer drugs and P-gp inhibitors in nanocarriers may synergistically increase drug accumulation and chemotherapeutic agent toxicity. The projection of desirable binding and effect may be procured initially by molecular docking of the inhibitor with P-gp, enabling the reduction of preliminary trials in formulation development. Here, P-gp-mediated efflux and several possible outcomes to overcome the problems associated with currently prevalent cancer treatments are highlighted.

Camptothesome-based combination nanotherapeutic regimen for improved colorectal cancer immunochemotherapy

Camptothesome is a sphingomyelin-conjugated camptothecin (SM-CSS-CPT) nanovesicle that fortified the therapeutic delivery of CPT in diverse cancer types. To mitigate the Camptothesome-induced IDO1 negative feedback mechanism, we had co-encapsulated, indoximod (IND, IDO1 inhibitor) into Camptothesome using doxorubicin-derived IND (DOX-IND). To maximize the therapeutic potential of DOX-IND/Camptothesome, herein, we first dissected the synergistic drug ratio (DOX-IND/SM-CSS-CPT) via systematical in vitro screening. DOX-IND/Camptothesome with optimal drug ratio synchronized in vivo drug delivery with significantly higher tumor uptake compared to free drugs. This optimum DOX-IND/Camptothesome outperformed the combination of Camptothesome, Doxil and IND or other IDO1 inhibitors (BMS-986205 or epacadostat) in treating mice bearing late-stage MC38 tumors, and combination with immune checkpoint blockade (ICB) enabled it to eradicate 60 % of large tumors. Further, this optimized co-delivery Camptothesome beat Folfox and Folfiri, two first-line combination chemotherapies for colorectal cancer in antitumor efficacy and exhibited no side effects as compared to the severe systemic toxicities associated with Folfox and Folfiri. Finally, we demonstrated that the synergistic DOX-IND/Camptothesome was superior to the combined use of Onivyde + Doxil + IND in curbing the advanced orthotopic CT26-Luc tumors and eliminated 40 % tumors with complete metastasis remission when cooperated with ICB, eliciting stronger anti-CRC immune responses and greater reversal of immunosuppression. These results corroborated that with precise optimal synergistic drug ratio, the therapeutic potential of DOX-IND/Camptothesome can be fully unleased, which warrants further clinical investigation to benefit the cancer patients.

Free drug and ROS-responsive nanoparticle delivery of synergistic doxorubicin and olaparib combinations to triple negative breast cancer models

Combinations of the topoisomerase II inhibitor doxorubicin and the poly (ADP-ribose) polymerase inhibitor olaparib offer potential drug-drug synergy for the treatment of triple negative breast cancers (TNBC). In this study we performed in vitro screening of combinations of these drugs, administered directly or encapsulated within polymer nanoparticles, in both 2D and in 3D spheroid models of breast cancer. A variety of assays were used to evaluate drug potency, and calculations of combination index (CI) values indicated that synergistic effects of drug combinations occurred in a molar-ratio dependent manner. It is suggested that the mechanisms of synergy were related to enhancement of DNA damage as shown by the level of double-strand DNA breaks, and mechanisms of antagonism associated with mitochondrial mediated cell survival, as indicated by reactive oxygen species (ROS) generation. Enhanced drug delivery and potency was observed with nanoparticle formulations, with a greater extent of doxorubicin localised to cell nuclei as evidenced by microscopy, and higher cytotoxicity at the same time points compared to free drugs. Together, the work presented identifies specific combinations of doxorubicin and olaparib which were most effective in a panel of TNBC cell lines, explores the mechanisms by which these combined agents might act, and shows that formulation of these drug combinations into polymeric nanoparticles at specific ratios conserves synergistic action and enhanced potency in vitro compared to the free drugs.

Advanced strategies for CRISPR/Cas9 delivery and applications in gene editing, therapy, and cancer detection using nanoparticles and nanocarriers

Cancer remains one of the deadliest diseases, and is characterised by the uncontrolled growth of modified human cells. Unlike infectious diseases, cancer does not originate from foreign agents. Though a variety of diagnostic procedures are available; their cost-effectiveness and accessibility create significant hurdles. Non-specific cancer symptoms further complicate early detection, leading to belated recognition of certain cancer. The lack of reliable biomarkers hampers effective treatment, as chemotherapy, radiation therapy, and surgery often result in poor outcomes and high recurrence rates. Genetic and epigenetic mutations play a crucial role in cancer pathogenesis, necessitating the development of alternate treatment methods. The advent of CRISPR/Cas9 technology has transformed molecular biology and exhibits potential for gene modification and therapy in various cancer types. Nonetheless, obstacles such as safe transport, off-target consequences, and potency must be overcome before widespread clinical use. Notably, this review delves into the multifaceted landscape of cancer research, highlighting the pivotal role of nanoparticles in advancing CRISPR/Cas9-based cancer interventions. By addressing the challenges associated with cancer diagnosis and treatment, this integrated approach paves the way for innovative solutions and improved patient outcomes.

An update on strategies for optimizing polymer-lipid hybrid nanoparticle-mediated drug delivery: exploiting transformability and bioactivity of PLN and harnessing intracellular lipid transport mechanism

INTRODUCTION

Polymer-lipid hybrid nanoparticle (PLN) is an emerging nanoplatform with distinct properties and functionalities from other nanocarrier systems. PLN can be optimized to overcome various levels of drug delivery barriers to achieve desired therapeutic outcomes via rational selection of polymer and lipid combinations based on a thorough understanding of their properties and interactions with therapeutic agents and biological systems.

AREAS COVERED

This review provides an overview of PLN including the motive and history of PLN development, types of PLN, preparation methods, attestations of their versatility, and design strategies to circumvent various barriers for increasing drug delivery accuracy and efficiency. It also highlights recent advances in PLN design including: rationale selection of polymer and lipid components to achieve spatiotemporal drug targeting and multi-targeted cascade drug delivery; utilizing the intracellular lipid transport mechanism for active targeting to desired organelles; and harnessing bioreactive lipids and polymers to magnify therapeutic effects.

EXPERT OPINION

A thorough understanding of properties of PLN components and their biofate is important for enhancing disease site targeting, deep tumor tissue penetration, cellular uptake, and intracellular trafficking of PLN. For futuristic PLN development, active lipid transport and dual functions of lipids and polymers as both nanocarrier material and pharmacological agents can be further explored.

A Snapshot of Selenium-enclosed Nanoparticles for the Management of Cancer

Among the primary causes of mortality in today's world is cancer. Many drugs are employed to give lengthy and severe chemotherapy and radiation therapy, like nitrosoureas (Cisplatin, Oxaliplatin), Antimetabolites (5-fluorouracil, Methotrexate), Topoisomerase inhibitors (Etoposide), Mitotic inhibitors (Doxorubicin); such treatment is associated with significant adverse effects. Antitumor antibiotics have side effects similar to chemotherapy and radiotherapy. Selenium (Se) is an essential trace element for humans and animals, and additional Se supplementation is required, particularly for individuals deficient in Se. Due to its unique features and high bioactivities, selenium nanoparticles (SeNPs), which act as a supplement to counter Se deficiency, have recently gained worldwide attention. This study presented a safer and more economical way of preparing stable SeNPs. The researcher has assessed the antiproliferative efficiency of SeNPs-based paclitaxel delivery systems against tumor cells in vitro with relevant mechanistic visualization. SeNPs stabilized by Pluronic F-127 were synthesized and studied. The significant properties and biological activities of PTX-loaded SeNPs on cancer cells from the lungs, breasts, cervical, and colons. In one study, SeNPs were formulated using chitosan (CTS) polymer and then incorporated into CTS/citrate gel, resulting in a SeNPs-loaded chitosan/citrate complex; in another study, CTS was used in the synthesis of SeNPs and then situated into CTS/citrate gel, resulting in Se loaded nanoparticles. These formulations were found to be more successful in cancer treatment.

Nanocracker capable of simultaneously reversing both P-glycoprotein and tumor microenvironment

Here, we describe a multidrug-resistant nanocracker (MDRC) that can treat multi-drug resistant (MDR) cancer by recognizing the acidic microenvironment and inhibiting two mechanisms of MDR such as P-glycoprotein (P-gp) and vacuolar-type ATPase (V-ATPase). MDRC is a liposome formulation co-loading pantoprazole (PZ) and paclitaxel (PTX). PZ acts as a chemosensitizer that enhances the MDR cancer treatment effect of PTX by disrupting the pH gradient and inhibiting P-gp. MDRC-encapsulated PZ and PTX have different release rates, with PZ released within 12 h and PTX sustained release for 48 h in the plasma. MDRC could increase cell uptake by inhibiting the P-gp overexpressed MCF-7/mdr cells and UV-2237M cells, which are human breast MDR cancer cells and murine fibrosarcoma cells, respectively. MDRC can also increase the cytotoxic efficacy of PTX by increasing intracellular pH. MDRC has a 10.5-fold reduced IC₅₀ value in the P-gp overexpressed human breast adenocarcinoma and a 6.3- to 9.5-fold reduced IC₅₀ value in the P-gp non-expressed human breast adenocarcinoma compared to the mixture of PZ and PTX, respectively. Intravenous injection of MDRC did not cause weight loss, liver dysfunction, or major organ toxicity. MDRC exhibited 80% complete remission of murine fibrosarcoma. The excellent therapeutic effect of MDRC on MDR tumors was accompanied by an increase in dendritic cell maturation and cytotoxic T cells. In other words, MDRC has the potential to terminate MDR therapy through the complete remission of MDR tumors.

Innovative nanotheranostics: Smart nanoparticles based approach to overcome breast cancer stem cells mediated chemo- and radioresistances

The alarming increase in the number of breast cancer patients worldwide and the increasing death rate indicate that the traditional and current medicines are insufficient to fight against it. The onset of chemo- and radioresistances and cancer stem cell-based recurrence make this problem harder, and this hour needs a novel treatment approach. Competent nanoparticle-based accurate drug delivery and cancer nanotheranostics like photothermal therapy, photodynamic therapy, chemodynamic therapy, and sonodynamic therapy can be the key to solving this problem due to their unique characteristics. These innovative formulations can be a better cargo with fewer side effects than the standard chemotherapy and can eliminate the stability problems associated with cancer immunotherapy. The nanotheranostic systems can kill the tumor cells and the resistant breast cancer stem cells by novel mechanisms like local hyperthermia and reactive oxygen species and prevent tumor recurrence. These theranostic systems can also combine with chemotherapy or immunotherapy approaches. These combining approaches can be the future of anticancer therapy, especially to overcome the breast cancer stem cells mediated chemo- and radioresistances. This review paper discusses several novel theranostic systems and smart nanoparticles, their mechanism of action, and their modifications with time. It explains their relevance and market scope in the current era. This article is categorized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease.

Camptothesome Potentiates PD-L1 Immune Checkpoint Blockade for Improved Metastatic Triple-Negative Breast Cancer Immunochemotherapy

In this study, we focus on investigating the therapeutic effects of camptothesome on treating metastatic triple-negative breast cancer (TNBC). We elucidate that camptothesome elicited stronger immunogenic cell death (ICD) compared to free camptothecin (CPT) and Onivyde in 4T1 TNBC cells. In addition, camptothesome is mainly internalized by the 4T1 and MDA-MB-231 cells through clathrin-mediated endocytosis based on the results of flow cytometry. Through real-time Lago optical imaging, camptothesome shows excellent tumor-targeting efficiency in orthotopic TNBC tumors. We demonstrate that camptothesome can upregulate programmed death-ligand 1 (PD-L1) in 4T1 tumors in an interferon gamma (IFN-γ)-dependent manner. Furthermore, the anti-TNBC efficacy studies reveal that camptothesome is superior to Onivyde and markedly potentiates PD-L1 immune checkpoint blockade therapy with complete lung metastasis remission in an orthotopic 4T1-Luc2 tumor model. This combination therapy eliciting robust cytotoxic T lymphocytes (CTL) response via boosting tumor-infiltrating cluster of differentiation 8 (CD8), calreticulin (CRT), high mobility group box 1 protein (HMGB-1), low-density lipoprotein receptor-related protein 1 (LRP1), IFN-γ, and granzyme B. Our work corroborates the promise of camptothesome in favorably modulating tumor immune microenvironment via inducing ICD to fortify the PD-L1 checkpoint blockade therapy for improved treatment of intractable TNBC.

Emerging nanotechnology-based therapeutics to combat multidrug-resistant cancer

Cancer often develops multidrug resistance (MDR) when cancer cells become resistant to numerous structurally and functionally different chemotherapeutic agents. MDR is considered one of the principal reasons for the failure of many forms of clinical chemotherapy. Several factors are involved in the development of MDR including increased expression of efflux transporters, the tumor microenvironment, changes in molecular targets and the activity of cancer stem cells. Recently, researchers have designed and developed a number of small molecule inhibitors and derivatives of natural compounds to overcome various mechanisms of clinical MDR. Unfortunately, most of the chemosensitizing approaches have failed in clinical trials due to non-specific interactions and adverse side effects at pharmacologically effective concentrations. Nanomedicine approaches provide an efficient drug delivery platform to overcome the limitations of conventional chemotherapy and improve therapeutic effectiveness. Multifunctional nanomaterials have been found to facilitate drug delivery by improving bioavailability and pharmacokinetics, enhancing the therapeutic efficacy of chemotherapeutic drugs to overcome MDR. In this review article, we discuss the major factors contributing to MDR and the limitations of existing chemotherapy- and nanocarrier-based drug delivery systems to overcome clinical MDR mechanisms. We critically review recent nanotechnology-based approaches to combat tumor heterogeneity, drug efflux mechanisms, DNA repair and apoptotic machineries to overcome clinical MDR. Recent successful therapies of this nature include liposomal nanoformulations, cRGDY-PEG-Cy5.5-Carbon dots and Cds/ZnS core–shell quantum dots that have been employed for the effective treatment of various cancer sub-types including small cell lung, head and neck and breast cancers.

Camptothesome elicits immunogenic cell death to boost colorectal cancer immune checkpoint blockade

Camptothesome is an innovative nanovesicle therapeutic comprising the sphingomyelin-derived camptothecin (CPT) lipid bilayer. In this work, we deciphered that Camptothesome was taken up by colorectal cancer (CRC) cells through primarily the clathrin-mediated endocytotic pathway and displayed the potential of eliciting robust immunogenic cancer cell death (ICD) via upregulating calreticulin, high mobility group box 1 protein (HMGB-1), and adenosine triphosphate (ATP), three hallmarks involved in the induction of ICD. In addition, use of dying MC38 tumor cells treated with Camptothesome as vaccine prevented tumor growth in 60% mice that received subsequent injection of live MC38 cells on the contralateral flank, validating Camptothesome was a legitimate ICD inducer in vivo. Camptothesome markedly reduced the acute bone marrow toxicity and gastrointestinal mucositis associated with free CPT and beat free CPT and Onivyde on anti-CRC efficacy and immune responses in a partially interferon gamma (IFN-γ)-dependent manner. Furthermore, Camptothesome enhanced the efficacy of immune checkpoint inhibitors to shrink late-stage orthotopic MC38 CRC tumors with diminished tumor metastasis and markedly prolonged mice survival.

pH-Sensitive Liposomes for Enhanced Cellular Uptake and Cytotoxicity of Daunorubicin in Melanoma (B16-BL6) Cell Lines

Daunorubicin (DNR) was delivered using a pH-sensitive liposomal system in B16-BL6 melanoma cell lines for enhanced cytotoxic effects. DNR was encapsulated within liposomes and CL as a component of the lipid bilayer. PEGylated pH-sensitive liposomes, containing CL, were prepared in the molar ratio of 40:30:5:17:8 for DOPE/cholesterol/DSPE-mPEG (2000)/CL/SA using the lipid film hydration method and loaded with DNR (drug: lipid ratio of 1:5). The CL liposomes exhibited high drug encapsulation efficiency (>90%), a small size (~94 nm), narrow size distribution (polydispersity index ~0.16), and a rapid release profile at acidic pH (within 1 h). Furthermore, the CL liposomes exhibited 12.5- and 2.5-fold higher cytotoxicity compared to DNR or liposomes similar to DaunoXome®. This study provides a basis for developing DNR pH-sensitive liposomes for melanoma treatment.

Advances in Nanomedicine Design: Multidisciplinary Strategies for Unmet Medical Needs

Globally, a rising burden of complex diseases takes a heavy toll on human lives and poses substantial clinical and economic challenges. This review covers nanomedicine and nanotechnology-enabled advanced drug delivery systems (DDS) designed to address various unmet medical needs. Key nanomedicine and DDSs, currently employed in the clinic to tackle some of these diseases, are discussed focusing on their versatility in diagnostics, anticancer therapy, and diabetes management. First-hand experiences from our own laboratory and the work of others are presented to provide insights into strategies to design and optimize nanomedicine- and nanotechnology-enabled DDS for enhancing therapeutic outcomes. Computational analysis is also briefly reviewed as a technology for rational design of controlled release DDS. Further explorations of DDS have illuminated the interplay of physiological barriers and their impact on DDS. It is demonstrated how such delivery systems can overcome these barriers for enhanced therapeutic efficacy and how new perspectives of next-generation DDS can be applied clinically.

Overview of the Influence of Silver, Gold, and Titanium Nanoparticles on the Physical Properties of PEDOT:PSS-Coated Cotton Fabrics

Metallic nanoparticles have been of interest to scientists, and they are now widely used in biomedical and engineering applications. The importance, categorization, and characterization of silver nanoparticles, gold nanoparticles, and titanium nanoparticles have been discussed. Poly(3,4-ethylenedioxythiophene) poly(styrenesulfonate) (PEDOT:PSS) is the most practical and reliable conductive polymer used in the manufacturing of conductive textiles. The effects of metallic nanoparticles on the performance of PEDOT:PSS thin films are discussed. The results indicated that the properties of PEDOT:PSS significantly depended on the synthesis technique, doping, post-treatment, and composite material. Further, electronic textiles known as smart textiles have recently gained popularity, and they offer a wide range of applications. This review provides an overview of the effects of nanoparticles on the physical properties of PEDOT:PSS-coated cotton fabrics.

A review of nanoparticle drug delivery systems responsive to endogenous breast cancer microenvironment

Breast cancer, as a malignant disease that seriously threatens women's health, urgently needs to be researched to develop effective and safe therapeutic drugs. Nanoparticle drug delivery systems (NDDS), provide a powerful means for drug targeting to the breast cancer, enhancing the bioavailability and reducing the adverse effects of anticancer drug. However, the breast cancer microenvironment together with heterogeneity of cancer, impedes the tumor targeting effect of NDDS. Breast cancer microenvironment, exerts endogenous stimuli, such as hypoxia, acidosis, and aberrant protease expression, shape a natural shelter for tumor growth, invasion and migration. On the basis of the ubiquitous of endogenous stimuli in the breast cancer microenvironment, researchers exploited them to design the stimuli-responsive NDDS, which response to endogenous stimulus, targeted release drug in breast cancer microenvironment. In this review, we highlighted the effect of the breast cancer microenvironment, summarized innovative NDDS responsive to the internal stimuli in the tumor microenvironment, including the material, the targeting groups, the loading drugs, targeting position and the function of stimuli-responsive nanoparticle drug delivery system. The limitations and potential applications of the stimuli-responsive nanoparticle drug delivery systems for breast cancer treatment were discussed to further the application.

Drug Resistance in Metastatic Breast Cancer: Tumor Targeted Nanomedicine to the Rescue

Breast cancer, specifically metastatic breast, is a leading cause of morbidity and mortality in women. This is mainly due to relapse and reoccurrence of tumor. The primary reason for cancer relapse is the development of multidrug resistance (MDR) hampering the treatment and prognosis. MDR can occur due to a multitude of molecular events, including increased expression of efflux transporters such as P-gp, BCRP, or MRP1; epithelial to mesenchymal transition; and resistance development in breast cancer stem cells. Excessive dose dumping in chemotherapy can cause intrinsic anti-cancer MDR to appear prior to chemotherapy and after the treatment. Hence, novel targeted nanomedicines encapsulating chemotherapeutics and gene therapy products may assist to overcome cancer drug resistance. Targeted nanomedicines offer innovative strategies to overcome the limitations of conventional chemotherapy while permitting enhanced selectivity to cancer cells. Targeted nanotheranostics permit targeted drug release, precise breast cancer diagnosis, and importantly, the ability to overcome MDR. The article discusses various nanomedicines designed to selectively target breast cancer, triple negative breast cancer, and breast cancer stem cells. In addition, the review discusses recent approaches, including combination nanoparticles (NPs), theranostic NPs, and stimuli sensitive or “smart” NPs. Recent innovations in microRNA NPs and personalized medicine NPs are also discussed. Future perspective research for complex targeted and multi-stage responsive nanomedicines for metastatic breast cancer is discussed.

Exploring the transformability of polymer-lipid hybrid nanoparticles and nanomaterial-biology interplay to facilitate tumor penetration, cellular uptake and intracellular targeting of anticancer drugs

BACKGROUND

Successful delivery of anticancer drugs to intracellular targets requires different properties of the nanocarrier to overcome multiple transport barriers. However, few nanocarrier systems, to date, possess such properties, despite knowledge about the biological fate of inorganic and polymeric nanocarriers in relation to their fixed size, shape and surface properties. Herein, a polymer-lipid hybrid nanoparticle (PLN) system is described with size and shape transformability and its mechanisms of cellular uptake and intracellular trafficking are studied.

METHODS

Pharmaceutical lipids were screened for use in transformable PLN. Mechanisms of cellular uptake and the role of fatty acid-binding proteins in intracellular trafficking of PLN were investigated in breast cancer cells. Intra-tumoral penetration and retention of doxorubicin (DOX) were evaluated by confocal microscopy.

RESULTS

The lead PLNs showed time-dependent size reduction and shape change from spherical to spiky shape. This transformability of PLNs and lipid trafficking pathways facilitated intracellular transport of DOX-loaded PLN (DOX-PLN) into mitochondria and nuclei. DOX-PLN significantly increased DOX penetration and retention over free DOX or non-transformable liposomal DOX particles at 4 h post-intravenous administration.

CONCLUSION

Transformability of PLN and lipid-biology interplay can be exploited to design new nanocarriers for effective drug delivery to tumor cells and intracellular targets.

Biogenic synthesis and cytotoxic effects of silver nanoparticles mediated by white rot fungi

Silver nanoparticles (AgNPs) were successfully synthesized using silver nitrate via the biological route using the culture filtrate of Ganoderma enigmaticum as well as Trametes ljubarskyi white rot fungi materials at room temperature. The proposed synthetic technique was applied for the first time for AgNPs preparation via the biological route through a low-cost pathway, which considered as an adequate direction of preparation compared to the commercial methods. This study reports the in vitro cytotoxic effect of biologically synthesized AgNPs in disposing of the human lung cancer cell line (A549) and human breast cancer cell (MCF-7) by using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay. In addition, the viability of the tested cell lines was tested after treatment for 24 h in the presence of the prepared nanoparticles. The obtained results indicated the reduced viability of cancer cell lines with improving concentrations of AgNPs (40-120 μg/mL) at 24 h. Furthermore, at 120 μg/mL concentration, the fungal nanoparticles showed substantial cytotoxic effects toward the treated cells. Consequently, the results designated that the biologically synthesized silver nanoparticles have effective behavior for treating A549 and MCF-7 cancer cells from the laboratory experiment approach; however, additional studies are required to validate these results in vivo models as anticancer agents depending on their cytotoxic activity.

Targeted nanoscale therapeutics for myocardial infarction

Nanoscale therapeutics have promise for the administration of therapeutic small molecules and biologics to the heart following myocardial infarction. Directed delivery to the infarcted region of the heart using minimally invasive routes is critical to this promise. In this review, we will discuss the advances and design considerations for two nanoscale therapeutics engineered to target the infarcted heart, nanoparticles and adeno-associated viruses.

H. El-kannishy S, Gardouh AR, K. Tawfik M, Faisal S, El-Mistekawy A, Salama A, Alomar SY, H. Eltrawy A, Yagub Aloyouni S, Zaitone SA. Chemopreventive Effect of 5-Flurouracil Polymeric Hybrid PLGA-Lecithin Nanoparticles against Colon Dysplasia Model in Mice and Impact on p53 Apoptosis

The use of 5-fluorouracil (5FU) is associated with multifaceted challenges and poor pharmacokinetics. Poly(lactic-co-glycolic acid)-lipid hybrid nanoparticles (PLNs)-based therapy has received attention as efficient carriers for a diversity of drugs. This study evaluated the in vivo chemotherapeutic and anti-proliferative efficacy of 5FU-loaded PLNs against 1,2-dimethylhydrazine (Di-MH) prompted colon dysplasia in mice compared to free 5FU. 5FU PLNs were prepared. Male Swiss albino mice were distributed to six experimental groups. Group 1: Saline group. All the other groups were injected weekly with Di-MH [20 mg/kg, s.c.]. Group 2: Di-MH induced colon dysplasia control group. Groups 3 and 4: Di-MH + free 5FU treated group [2.5 and 5 mg/kg]. Groups 5 and 6: Di-MH + 5FU-PLNs treated group [2.5 and 5 mg/kg]. Free 5FU and 5FU-PLNs doses were administered orally, twice weekly. Treatment with 5FU-PLNs induced a higher cytoprotective effect compared to free 5FU as indicated by lower mucosal histopathologic score and reduction in number of Ki-67 immunpositive proliferating nuclei. Additionally, there was significant upregulation of p53 and caspase 3 genes in colon specimens. Our results support the validity of utilizing the PLNs technique to improve the chemopreventive action of 5FU in treating colon cancer.

A new drug testing platform based on 3D tri-culture in lab-on-a-chip devices

Drug discovery has a 90% rate of failure because preclinical platforms for drug testing do not mimic the in vivo conditions. Doxorubicin (DOX) is a commonly used drug to treat breast cancer patients even though it has side effects. Lab-on-a-chip (LOC) devices provide spatial control at the micrometer scale and can thus emulate the cancer microenvironment. Here, using a multidisciplinary approach, a new drug testing platform based on 3D tri-culture in LOC devices was developed. Breast cancer cells alone or with normal mammary epithelial cells and macrophages were cultured in matrigel in LOC devices. The platform was used to test DOX and (R)-4'-methylklavuzon (KLA), which is a new anti-cancer drug candidate. Results showed that DOX and KLA were equally effective on breast cancer cells in 3D monoculture. KLA produced 26% less death for breast cancer cells than DOX in 3D tri-culture. More importantly, DOX was not selective between breast cancer cells and normal mammary epithelial cells in 3D tri- culture whereas KLA caused 56% less cell death than DOX for normal mammary epithelial cells. Results strongly recommend that 3D tri-culture in LOC devices be used for assessment of drug toxicity at the preclinical stage.

Exciting Potential of Nanoparticlized Lipidic System for Effective Treatment of Breast Cancer and Clinical Updates: A Translational Prospective

Breast cancer (BC) is a multifactorial disease and becoming a major health issue in women throughout the globe. BC is a malignant type of cancer which results from transcriptional changes in proteins and genes. Besides the availability of modern medicines and detection tools, BC has become a topmost deadly disease and its cure still remains challenging. Nanotechnology based approaches are being employed for the diagnosis and treatment of BC at clinical stages. Nanosystems have a significant role in the study of the interaction of malignant cells with their microenvironment through receptor-based targeted approach. Nowadays, lipid-based nanocarriers are being popularized in the domain of pharmaceutical and medical biology for cancer therapy. Lipidic nanoparticlized systems (LNPs) have proven to have high loading efficiency, less toxicity, improved therapeutic efficacy, enhanced bioavailability and stability of the bioactive compounds compared to traditional drug delivery systems. In the present context, several LNPs based formulations have been undertaken in various phases of clinical trials in different countries. This review highlights the importance of chemotherapeutics based lipidic nanocarriers and their anticipated use for the treatment of BC. Furthermore, the clinical trials and future prospective of LNPs have been widely elaborated.

Effect of Surface Modification with Hydrocarbyl Groups on the Exocytosis of Nanoparticles

Designing nanoparticles (NPs) with desirable cell type-specific exocytosis properties, say promoting their exocytosis from scavenging cell types (e.g., macrophages and endothelial cells) or suppressing their exocytosis from target disease cell types (e.g., cancer cells), improves the application of nanomedicines. However, the design parameters available for tuning the exocytosis of NPs remain scarce in the "nano-cell" literature. Here, we demonstrate that surface modification of NPs with hydrocarbyl functional groups, commonly found in biomolecules and NP-based drug carriers, is a critical parameter for tuning the exocytosis of NPs from RAW264.7 macrophages, C166 endothelial cells, and HeLa epithelial cancer cells. To exclude the effect of hydrophobicity, we prepare a collection of hydrophilic NPs that bear a gold NP (AuNP) core, a dense polyethylene glycol (PEG) shell, and different types of hydrocarbyl groups (X) that are attached to the distal end of the PEG strands (termed "Au@PEG-X NPs"). For all three cell types tested, modification of NPs with straight-chain dodecane leads to a >10-fold increase in the level of cellular uptake, drastically higher than those of all other types of X tested. However, the probability of exocytosis of NPs significantly depends on the types of cell and X. Notably, NPs modified with cyclododecanes are most likely to be exocytosed by RAW264.7 and C166 cells (but not HeLa cells), accompanied by the release of intralumenal vesicles to the extracellular milieu. These data suggest a reductionist approach for rationally assembling bionanomaterials for nanomedicine applications by using hydrocarbyl functional groups as building blocks.

Mahonia aquifolium Extracts Promote Doxorubicin Effects against Lung Adenocarcinoma Cells In Vitro

Mahonia aquifolium and its secondary metabolites have been shown to have anticancer potential. We performed MTT, scratch, and colony formation assays; analyzed cell cycle phase distribution and doxorubicin uptake and retention with flow cytometry; and detected alterations in the expression of genes involved in the formation of cell-cell interactions and migration using quantitative real-time PCR following treatment of lung adenocarcinoma cells with doxorubicin, M. aquifolium extracts, or their combination. MTT assay results suggested strong synergistic effects of the combined treatments, and their application led to an increase in cell numbers in the subG1 phase of the cell cycle. Both extracts were shown to prolong doxorubicin retention time in cancer cells, while the application of doxorubicin/extract combination led to a decrease in MMP9 expression. Furthermore, cells treated with doxorubicin/extract combinations were shown to have lower migratory and colony formation potentials than untreated cells or cells treated with doxorubicin alone. The obtained results suggest that nontoxic M. aquifolium extracts can enhance the activity of doxorubicin, thus potentially allowing the application of lower doxorubicin doses in vivo, which may decrease its toxic effects in normal tissues.

Co-delivery of doxorubicin, docosahexaenoic acid, and α-tocopherol succinate by nanostructured lipid carriers has a synergistic effect to enhance antitumor activity and reduce toxicity

Doxorubicin (DOX) is widely used in cancer treatment, however, its use is often limited due to its side effects. To avoid these shortcomings, the encapsulation of DOX into nanocarriers has been suggested. Herein, we proposed a novel nanostructured lipid carrier (NLC) formulation loading DOX, docosahexaenoic acid (DHA), and α-tocopherol succinate (TS) for cancer treatment. DHA is an omega-3 fatty acid and TS is a vitamin E derivative. It has been proposed that these compounds can enhance the antitumor activity of chemotherapeutics. Thus, we hypothesized that the combination of DOX, DHA, and TS in NLC (NLC-DHA-DOX-TS) could increase antitumor efficacy and also reduce toxicity. NLC-DHA-DOX-TS was prepared using emulsification-ultrasound. DOX was incorporated after preparing the NLC, which prevented its degradation during manufacture. High DOX encapsulation efficiency was obtained due to the ion-pairing with TS. This ion-pairing increases lipophilicity of DOX and reduces its crystallinity, contributing to its encapsulation in the lipid matrix. Controlled DOX release from the NLC was observed in vitro, with increased drug release at the acidic environment. In vitro cell studies indicated that DOX, DHA, and TS have synergistic effects against 4T1 tumor cells. The in vivo study showed that NLC-DHA-DOX-TS exhibited the greatest antitumor efficacy by reducing tumor growth in 4T1 tumor-bearing mice. In addition, this formulation reduced mice mortality, prevented lung metastasis, and decreased DOX-induced toxicity to the heart and liver, which was demonstrated by hematologic, biochemical, and histologic analyses. These results indicate that NLC-DHA-DOX-TS may be a promising carrier for breast cancer treatment.

In situ forming implants exposed to ultrasound enhance therapeutic efficacy in subcutaneous murine tumors

In situ forming implants (ISFIs) allow for a high initial intratumoral concentration and sustained release of the chemotherapeutic. However, clinical translation is impeded primarily due to limited drug penetration from the tumor/boundary interface and poor intratumoral drug retention. Therapeutic ultrasound (TUS) has become a popular approach for improving drug penetration of transdermal devices and increasing cellular uptake of nanoparticles. These effects are driven by the mechanical and thermal bioeffects associated with TUS. In this study, we characterize the released drug penetration, retention, and overall therapeutic response when exposing ISFI to the combination of the mechanical and thermal effects of TUS (C-TUS). ISFIs were intratumorally injected into subcutaneous murine tumors then exposed to C-TUS (exposure: 5 min, duty factor: 0.33, frequency: 3 MHz, intensity: 2.2 W/cm2, pulse duration: 2 ms, pulse repetition frequency: 165 Hz, effective radiating area: 5 cm2, energy delivered: 896 J, time average intensity: 0.88 W/cm2). Tumors treated with the combination of ISFI + C-TUS demonstrated a 2.5-fold increase in maximum drug penetration and a 3-fold increase in drug retention at 5- and 8-days post-injection, respectively, compared to ISFIs without TUS exposure. These improvements in drug penetration and retention translated into an enhanced therapeutic response. Mice treated with ISFI + C-TUS showed a 62.6% reduction in tumor progression, a 50.0% increase in median survival time, and a 26.6% increase in necrotic percentage compared to ISFIs without TUS exposure. Combining intratumoral ISFIs with TUS may be beneficial for addressing some long-standing challenges with local drug delivery in cancer treatment and may serve as a viable noninvasive method to improve the poor clinical success of local drug delivery systems.

Pérez R, Ravula S, M. Strongin R, McDonough K, M. Warner I. Comparison of Chemotherapeutic Activities of Rhodamine-Based GUMBOS and NanoGUMBOS

Rhodamine derivatives have been widely investigated for their mitochondrial targeting and chemotherapeutic properties that result from their lipophilic cationic structures. In previous research, we have found that conversion of Rhodamine 6G into nanoGUMBOS, i.e., nanomaterials derived from a group of uniform materials based on organic salts (GUMBOS), led to selective chemotherapeutic toxicity for cancer cells over normal cells. Herein, we investigate the chemotherapeutic activity of GUMBOS derived from four different rhodamine derivatives, two bearing an ester group, i.e., Rhodamine 123 (R123) and SNAFR-5, and two bearing a carboxylic acid group, i.e., rhodamine 110 (R110) and rhodamine B (RB). In this study, we evaluate (1) relative hydrophobicity via octanol-water partition coefficients, (2) cytotoxicity, and (3) cellular uptake in order to evaluate possible structure-activity relationships between these different compounds. Intriguingly, we found that while GUMBOS derived from R123 and SNAFR-5 formed nanoGUMBOS in aqueous medium, no distinct nanoparticles are observed for RB and R110 GUMBOS. Further investigation revealed that the relatively high water solubility of R110 and RB GUMBOS hinders nanoparticle formation. Subsequently, while R123 and SNAFR-5 displayed selective chemotherapeutic toxicity similar to that of previously investigated R6G nanoGUMBOS, the R110 and RB GUMBOS were lacking in this property. Additionally, the chemotherapeutic toxicities of R123 and SNAFR-5 nanoGUMBOS were also significantly greater than R110 and RB GUMBOS. Observed results were consistent with decreased cellular uptake of R110 and RB as compared to R123 and SNAFR-5 compounds. Moreover, these results are also consistent with previous observations that suggest that nanoparticle formation is critical to the observed selective chemotherapeutic properties as well as the chemotherapeutic efficacy of rhodamine nanoGUMBOS.

Synthesis and Antitumor Activity of Doxycycline Polymeric Nanoparticles: Effect on Tumor Apoptosis in Solid Ehrlich Carcinoma

Objectives: The aim of this study was to prepare doxycycline polymeric nanoparticles (DOXY-PNPs) with hope to enhance its chemotherapeutic potential against solid Ehrlich carcinoma (SEC). Methods: Three DOXY-PNPs were formulated by nanoprecipitation method using hydroxypropyl methyl cellulose (HPMC) as a polymer. The prepared DOXY-PNPs were evaluated for the encapsulation efficiency (EE%), the drug loading capacity, particle size, zeta potential (ZP) and the in-vitro release for selection of the best formulation. PNP number 3 was selected for further biological testing based on the best pharmaceutical characters. PNP3 (5 and 10 mg/kg) was evaluated for the antitumor potential against SEC grown in female mice by measuring the tumor mass as well as the expression and immunohistochemical staining for the apoptosis markers; caspase 3 and BAX. Results: The biological study documented the greatest reduction in tumor mass in mice treated with PNP3. Importantly, treatment with 5 mg/kg of DOXY-PNPs produced a similar chemotherapeutic effect to that produced by 10 mg/kg of free DOXY. Further, a significant elevation in mRNA expression and immunostaining for caspase 3 and BAX was detected in mice group treated with DOXY-PNPs. Conclusions: The DOXY-PNPs showed greater antitumor potential against SEC grown in mice and greater values for Spearman’s correlation coefficients were detected when correlation with tumor mass or apoptosis markers was examined; this is in comparison to free DOXY. Hence, DOXY-PNPs should be tested in other tumor types to further determine the utility of the current technique in preparing chemotherapeutic agents and enhancing their properties.

Doxorubicin-loaded iron oxide nanoparticles for glioblastoma therapy: a combinational approach for enhanced delivery of nanoparticles

Although doxorubicin (DOX) is an effective anti-cancer drug with cytotoxicity in a variety of different tumors, its effectiveness in treating glioblastoma multiforme (GBM) is constrained by insufficient penetration across the blood–brain barrier (BBB). In this study, biocompatible magnetic iron oxide nanoparticles (IONPs) stabilized with trimethoxysilylpropyl-ethylenediamine triacetic acid (EDT) were developed as a carrier of DOX for GBM chemotherapy. The DOX-loaded EDT-IONPs (DOX-EDT-IONPs) released DOX within 4 days with the capability of an accelerated release in acidic microenvironments. The DOX-loaded EDT-IONPs (DOX-EDT-IONPs) demonstrated an efficient uptake in mouse brain-derived microvessel endothelial, bEnd.3, Madin–Darby canine kidney transfected with multi-drug resistant protein 1 (MDCK-MDR1), and human U251 GBM cells. The DOX-EDT-IONPs could augment DOX’s uptake in U251 cells by 2.8-fold and significantly inhibited U251 cell proliferation. Moreover, the DOX-EDT-IONPs were found to be effective in apoptotic-induced GBM cell death (over 90%) within 48 h of treatment. Gene expression studies revealed a significant downregulation of TOP II and Ku70, crucial enzymes for DNA repair and replication, as well as MiR-155 oncogene, concomitant with an upregulation of caspase 3 and tumor suppressors i.e., p53, MEG3 and GAS5, in U251 cells upon treatment with DOX-EDT-IONPs. An in vitro MDCK-MDR1-GBM co-culture model was used to assess the BBB permeability and anti-tumor activity of the DOX-EDT-IONPs and DOX treatments. While DOX-EDT-IONP showed improved permeability of DOX across MDCK-MDR1 monolayers compared to DOX alone, cytotoxicity in U251 cells was similar in both treatment groups. Using a cadherin binding peptide (ADTC5) to transiently open tight junctions, in combination with an external magnetic field, significantly enhanced both DOX-EDT-IONP permeability and cytotoxicity in the MDCK-MDR1-GBM co-culture model. Therefore, the combination of magnetic enhanced convective diffusion and the cadherin binding peptide for transiently opening the BBB tight junctions are expected to enhance the efficacy of GBM chemotherapy using the DOX-EDT-IONPs. In general, the developed approach enables the chemotherapeutic to overcome both BBB and multidrug resistance (MDR) glioma cells while providing site-specific magnetic targeting.

Does Pharmacodynamics of Drugs Change After Presenting them as Nanoparticles Like their Pharmacokinetics?

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Nowadays, the breakthrough in different medical branches makes it feasible to designate new methods of drug delivery to achieve the most cost-effective and the least unpleasant consequenceimposing solutions to overcome a wide range of diseases.

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Nanoparticle (NP) drugs entered the therapeutic system, especially in cancer chemotherapy. These drugs are quite well-known for two traits of being long-acting and less toxic. For a long time, it has been investigated how NPs will change the kinetics of drugs. However, there are a few studies that inclined their attention to how NPs affect the dynamics of drugs. In this review, the latter point will mainly be discussed in an example-based manner. Besides, other particular features of NPs will be briefly noted.

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NPs are capable of affecting the biologic system as much as a drug. Moreover, NPs could arise a wide variety of effects by triggering their own receptors. NPs are able to change a receptor function and manipulate its downstream signaling cascade.

A Precise Nanostructure of Folate-Overhung Mitoxantrone DNA Tetrahedron for Targeted Capture Leukemia

Regular chemotherapy cannot eliminate leukemic cells, due to the sparse distribution of cancer cells in leukemia patients. Here, we report a precise nanostructure of folate-overhung mitoxantrone DNA tetrahedron that enables the treatment of leukemic cells by targeted action. Folate is used as a targeting molecule and synthesized with DNA strand in forming the folate-overhang DNA complement, and the complement is then separately base-paired onto six sides of the fabricated DNA tetrahedron. Mitoxantrone is used as an anticancer agent and intercalated into the double strands of the folate-overhung DNA tetrahedron for drug loading. The evaluation studies are performed on leukemia BALL-1 and K562 cells. The results demonstrate that the folate-overhung mitoxantrone DNA tetrahedra (approximately 25 nm) are able to target leukemic cells, transport across the nuclei membrane, induce the apoptosis, and enhance the overall efficacy of treating leukemic cells in vitro and in leukemia-bearing mice. This study provides a potential drug-containing DNA nanostructure, to clean the sparsely distributed leukemic cells in patients.

Anticancer Effects of Polyisoprenoid From Nypa fruticans Leaves by Controlling Expression of p53, EGFR, PI3K, AKT1, and mTOR Genes in Colon Cancer (WiDr) Cells

The current research seeks to examine the anticancer effect of polyisoprenoids from mangrove palm, Nypa fruticans, leaves in WiDr cells by analyzing the cell cycles of cancer and regulating the expression of p53, epidermal growth factor receptor (EGFR), PI3K, AKT1, and mammalian target of rapamycin (mTOR) genes by using the reverse transcription-polymerase chain reaction (RT-PCR). An inhibited cell cycle analysis was conducted using the flow cytometry, and the upregulation or downregulation of the expression of p53, EGFR, PI3K, AKT1, and mTOR genes was obtained using RT-PCR. The data were then statistically analyzed using one-way analysis of variance by a post hoc test, a parametric statistical analysis using Tukey’s honest significant difference. Polyisoprenoids in N. fruticans extracts worked as chemotheraupetic in the G0-G1 cycle is 79.0%, however, with positive control 5-fluorouracil as 88.1% and are carried out by the specific upregulation of the expression of the p53 gene and the downregulation of the expression of the EGFR, PI3K, AKT1, and mTOR genes. This study can also explain the significant pharmacological properties of the leaves of the species N. fruticans that work specifically in the G0-G1 phase to upregulate the expression of the p53 gene and downregulate the expression of the EGFR, PI3K, AKT1, and mTOR genes. This study also revealed polyisoprenoid (100% dolichol), which blocked the growth and development of WiDr colon cancer cells.

Improving Treatment Efficacy of In Situ Forming Implants via Concurrent Delivery of Chemotherapeutic and Chemosensitizer

P-glycoprotein (Pgp), a member of the ATP-binding cassette family, is one of the major causes of multidrug resistance in tumors. Current clinical treatments to overcome MDR involve the co-delivery of a Pgp inhibitor and a chemotherapeutic. A concern for this treatment that has led to varied clinical trial success is the associated systemic toxicities involving endogenous Pgp. Local drug delivery systems, such as in situ forming implants (ISFIs), alleviate this problem by delivering a high concentration of the drug directly to the target site without the associated systemic toxicities. ISFIs are polymeric drug solutions that undergo a phase transition upon injection into an aqueous environment to form a solid drug eluting depot allowing for a high initial intratumoral drug concentration. In this study, we have developed an ISFI capable of overcoming the Pgp resistance by co-delivering a chemotherapeutic, Doxorubicin (Dox), with a Pgp inhibitor, either Pluronic P85 or Valspodar (Val). Studies investigated in vitro cytotoxicity of Dox when combined with either Pgp inhibitor, effect of the inhibitors on release of Dox from implants in PBS, in vivo Dox distribution and retention in a subcutaneous flank colorectal murine tumor, and therapeutic response characterized by tumor growth curves and histopathology. Dox + Val showed a 4-fold reduction in the 50% lethal dose (LD₅₀) after 48 hours. Concurrent delivery of Dox and Val showed the greatest difference at 16 days post injection for both Dox penetration and retention. This treatment group had a 5-fold maximum Dox penetration compared to Dox alone ISFIs (0.53 ± 0.22 cm vs 0.11 ± 0.11 cm, respectively, from the center of the ISFI). Additionally, there was a 3-fold increase in normalized total intratumoral Dox intensity with the Dox + Val ISFIs compared to Dox alone ISFIs (0.54 ± 0.11 vs 0.18 ± 0.09, respectively). Dox + Val ISFIs showed a 2-fold reduction in tumor growth and a 27.69% increase in necrosis 20 days post-injection compared to Dox alone ISFIs. These findings demonstrate that co-delivery of Dox and Val via ISFI can avoid systemic toxicity issues seen with clinical Pgp inhibitors.

Effect simultaneous delivery with P-glycoprotein inhibitor and nanoparticle administration of doxorubicin on cellular uptake and in vitro anticancer activity

Multidrug resistance (MDR) is the most common problem of inadequate therapeutic response in tumor cells. Many trials has been developed to overcome drug efflux by P-glycoprotein (P-gp). For instance, co-administration of a number of drugs called chemosensitizers or MDR modulators with a chemotherapeutic agent to inhibit drug efflux. But for optimal synergy, the drug and inhibitor combination may need to be temporally colocalized in the tumor cells. In this study, we encapsulated the Ver and Dox in PLGA nanoparticles to inhibit the P-gp drug efflux in breast cancer. Moreover, the effect of either Dox solution (Dox_S), Dox nanoparticles (Dox_NP), Dox_S + Ver_S, Dox_NP + Ver_S, Dox_NP + Ver_NP or Dox-Ver_NP was evaluated. It was found that co administration of Dox_NP with Ver_NP (70.76%) showed similar cellular uptake of Dox to Dox/Ver combination solution (70.62%). However it is observed that Dox_NP + Ver_NP has the highest apoptotic activity (early apoptotic 13.52 ± 0.06%, late apoptotic 53.94 ± 0.15%) on human breast adenocarcinoma (MCF 7) cells. Hence, it is suggested that Dox_NP + Ver_NP is a promising administration for tumor therapy.

Gene/paclitaxel co-delivering nanocarriers prepared by framework-induced self-assembly for the inhibition of highly drug-resistant tumors

While drug resistance has been recognized as the main cause of unsuccessful chemotherapy, the efficient inhibition of highly drug-resistant tumors still remains a significant challenge, especially for in vivo treatments. Drug resistance has been associated with the high expression of the multi-drug resistance gene 1 (MDR1), which can encode an efflux transporter known as P-glycoprotein (P-gp) that is located in the cellular membrane. Therefore, the combined delivery of MDR1-inhibited genes and chemotherapeutic drugs is anticipated to enable the effective inhibition of drug-resistant tumors. Herein, highly paclitaxel (PTX)-resistant ovarian (OV) cancer with a drug resistance index reaching up to ~ 60 was chosen to evaluate the performance of an efficient gene/drug co-delivery nanocarrier. Inspired by the self-assembly that occurs in cells and exosomes, we designed a biomimetic lipid/dextran hybrid nanocarrier with a diameter of ~ 100 nm to enhance the endocytosis and the efficiency of drug/gene release within the cells. This nanocarrier was fabricated via the frame-guided self-assembly of lipid amphiphiles on the surfaces of redox-cleavable dextran-based nanogels. The anionic MDR1-siRNA and the hydrophobic drug PTX were respectively loaded into the cationic lipid shell and the hydrophobic internal core of the hybrid nanocarriers. MDR1-siRNA can knock down MDR1, promoting the accumulation of PTX in cells, and thus is expected to achieve an efficient inhibitory effect against highly PTX-resistant cancer cells. Both in vitro and in vivo studies revealed that this dual-delivery system significantly enhanced the therapeutic effect in comparison with that provided by a PTX-only system. Thus, the construction of gene/chemo co-delivered lipid/dextran nanocarriers provides a new strategy to inhibit highly drug-resistant tumors both in vitro and in vivo. In addition, this work will contribute toward the development of urgently needed tumor nanotherapy that is able to overcome drug resistance while also offering an unmatched range of effective therapeutic nanocarriers. STATEMENT OF SIGNIFICANCE: The biomimetic lipid/dextran hybrid nanocarrier with a diameter of ~ 100 nm, which was fabricated via the frame-guided self-assembly of lipid amphiphiles onto the surface of redox-cleavable dextran-based nanogels, provides a model carrier to co-deliver MDR1-siRNA and PTX.  The MDR1-siRNA/PTX co-loaded biomimetic lipid/dextran hybrid nanocarriers demonstrate good capability in overcoming the PTX-resistance in highly chemo-resistant human ovarian (OV) cancer cells both in vitro and in vivo.

Polymeric Nanoparticles for the Treatment of Malignant Gliomas

Malignant gliomas are one of the deadliest forms of brain cancer and despite advancements in treatment, patient prognosis remains poor, with an average survival of 15 months. Treatment using conventional chemotherapy does not deliver the required drug dose to the tumour site, owing to insufficient blood brain barrier (BBB) penetration, especially by hydrophilic drugs. Additionally, low molecular weight drugs cannot achieve specific accumulation in cancerous tissues and are characterized by a short circulation half-life. Nanoparticles can be designed to cross the BBB and deliver their drugs within the brain, thus improving their effectiveness for treatment when compared to administration of the free drug. The efficacy of nanoparticles can be enhanced by surface PEGylation to allow more specificity towards tumour receptors. This review will provide an overview of the different therapeutic strategies for the treatment of malignant gliomas, risk factors entailing them as well as the latest developments for brain drug delivery. It will also address the potential of polymeric nanoparticles in the treatment of malignant gliomas, including the importance of their coating and functionalization on their ability to cross the BBB and the chemistry underlying that.

Bio-responsive Bletilla striata polysaccharide-based micelles for enhancing intracellular docetaxel delivery

The aim of this study was to design a pH- and redox-dual responsive Bletilla striata polysaccharide (BSP)-based copolymer to enhance anti-tumor drugs release at tumor sites and improve the therapeutic effect. The copolymer was synthesized using stearic acid (SA) and cystamine via a disulfide linkage and characterized using 1H-Nuclear Magnetic Resonance spectroscopy and Fourier Transform Infrared spectroscopy. The BSP-ss-SA copolymer could self-assemble into micelle in an aqueous environment and could encapsulate docetaxel therein. Its inhibitory effects on HepG2 cells and 4 T1 cells were determined. Besides, the anti-cancer effects in vivo and histopathological study of 4 T1-bearing tumor mice were also evaluated. Docetaxel-loaded BSP-ss-SA micelles showed significant pH-sensitive release behavior, supplying a greater drug release percentage in pH 5.0 media compared to pH 7.4 media. BSP-ss-SA micelles exhibited a clear redox-responsive release property in pH 7.4 media whereas the similar cumulative release percentage of docetaxel from BSP-ss-SA micelles in pH 5.0 media in the presence and absence of DL-dithiothreitol. The Docetaxel-loaded BSP-ss-SA micelles clearly inhibited the proliferation of HepG2 and 4 T1 cells compared with docetaxel solution. The results of MTT and histopathological study indicated that BSP-ss-SA copolymer exhibited good blood compatibility. The BSP-ss-SA copolymer may be used as carriers to deliver anti-tumor drugs to special tumor tissues.

Incorporation of doxorubicin in different polymer nanoparticles and their anticancer activity

Background: Nanoparticles are under investigation as carrier systems for anticancer drugs. The expression of efflux transporters such as the ATP-binding cassette (ABC) transporter ABCB1 is an important resistance mechanism in therapy-refractory cancer cells. Drug encapsulation into nanoparticles has been shown to bypass efflux-mediated drug resistance, but there are also conflicting results. To investigate whether easy-to-prepare nanoparticles made of well-tolerated polymers may circumvent transporter-mediated drug efflux, we prepared poly(lactic-co-glycolic acid) (PLGA), polylactic acid (PLA), and PEGylated PLGA (PLGA-PEG) nanoparticles loaded with the ABCB1 substrate doxorubicin by solvent displacement and emulsion diffusion approaches and assessed their anticancer efficiency in neuroblastoma cells, including ABCB1-expressing cell lines, in comparison to doxorubicin solution. Results: The resulting nanoparticles covered a size range between 73 and 246 nm. PLGA-PEG nanoparticle preparation by solvent displacement led to the smallest nanoparticles. In PLGA nanoparticles, the drug load could be optimised using solvent displacement at pH 7 reaching 53 µg doxorubicin/mg nanoparticle. These PLGA nanoparticles displayed sustained doxorubicin release kinetics compared to the more burst-like kinetics of the other preparations. In neuroblastoma cells, doxorubicin-loaded PLGA-PEG nanoparticles (presumably due to their small size) and PLGA nanoparticles prepared by solvent displacement at pH 7 (presumably due to their high drug load and superior drug release kinetics) exerted the strongest anticancer effects. However, nanoparticle-encapsulated doxorubicin did not display increased efficacy in ABCB1-expressing cells relative to doxorubicin solution. Conclusion: Doxorubicin-loaded nanoparticles made by different methods from different materials displayed substantial discrepancies in their anticancer activity at the cellular level. Optimised preparation methods resulted in PLGA nanoparticles characterised by increased drug load, controlled drug release, and high anticancer efficacy. The design of drug-loaded nanoparticles with optimised anticancer activity at the cellular level is an important step in the development of improved nanoparticle preparations for anticancer therapy. Further research is required to understand under which circumstances nanoparticles can be used to overcome efflux-mediated resistance in cancer cells.

Fabrication Of Dual pH/redox-Responsive Lipid-Polymer Hybrid Nanoparticles For Anticancer Drug Delivery And Controlled Release

BACKGROUND

The development of biocompatible nanocarriers that can efficiently encapsulate and deliver anticancer drug to the tumor site and provide controlled release of cargos in response to the specific cues for cancer therapy is of great significance.

METHODS

In this work, dual pH/redox-responsive fabrication of hybrid lipid-polymer nanoparticles (LPNPs) self-assembled from amphiphilic polymer poly(ethylene glycol) methyl ether-grafted disulfide-poly(β-amino esters) (PBAE-ss-mPEG) and PEGylated lipid were prepared and used as drug delivery carriers. The optimization of PEGylated lipid modification was confirmed by analysis of particle size, polydispersity index (PDI), cellular uptake, serum stability, and drug loading capacity. The pK b value of LPNPs was determined as 6.55, indicating the pH-sensitivity. The critical micelle concentration (CMC) values and zeta-potential of LPNPs at different pH values were investigated to confirm its pH-sensitivity. The morphology of LPNPs before and after incubation with reducing agent was imaged to study the redox-responsibility.

RESULTS

The in vitro results showed that the drug had controlled release from LPNPs triggered by low pH and high concentration of reducing agent. Furthermore, the cytotoxicity of LPNPs was very low, and the doxorubicin (DOX)-loaded LPNPs could efficiently induce the death of tumor cells in comparison to free DOX.

CONCLUSION

All results demonstrated that the fabricated LPNPs could be potential anticancer drug delivery carriers with a pH/redox-triggered drug release profile, and PEGylated lipid modification might be a useful method to fabricate the drug delivery platform.

Endovascular Ion Exchange Chemofiltration Device Reduces Off-Target Doxorubicin Exposure in a Hepatic Intra-arterial Chemotherapy Model

Purpose

To determine if endovascular chemofiltration with an ionic device (ChemoFilter [CF]) can be used to reduce systemic exposure and off-target biodistribution of doxorubicin (DOX) during hepatic intra-arterial chemotherapy (IAC) in a preclinical model.

Materials and Methods

Hepatic IAC infusions were performed in six pigs with normal livers. Animals underwent two 10-minute intra-arterial infusions of DOX (200 mg) into the common hepatic artery. Both the treatment group and the control group received initial IAC at 0 minutes and a second dose at 200 minutes. Prior to the second dose, CF devices were deployed in and adjacent to the hepatic venous outflow tract of treatment animals. Systemic exposure to DOX was monitored via blood samples taken during IAC procedures. After euthanasia, organ tissue DOX concentrations were analyzed. Alterations in systemic DOX exposure and biodistribution were compared by using one-tailed t tests.

Results

CF devices were well tolerated, and no hemodynamic, thrombotic, or immunologic complications were observed. Animals treated with a CF device had a significant reduction in systemic exposure when compared with systemic exposure in the control group (P <.009). Treatment with a CF device caused a significant decrease in peak DOX concentration (31%, P <.01) and increased the time to maximum concentration (P <.03). Tissue analysis was used to confirm significant reduction in DOX accumulation in the heart and kidneys (P <.001 and P <.022, respectively). Mean tissue concentrations in the heart, kidneys, and liver of animals treated with CF compared with those in control animals were 14.2 μg/g ± 1.9 (standard deviation) versus 26.0 μg/g ± 1.8, 46.4 μg/g ± 4.6 versus 172.6 μg/g ± 40.2, and 217.0 μg/g ± 5.1 versus 236.8 μg/g ± 9.0, respectively. Fluorescence imaging was used to confirm in vivo DOX binding to CF devices.

Conclusion

Reduced systemic exposure and heart bioaccumulation of DOX during local-regional chemotherapy to the liver can be achieved through in situ adsorption by minimally invasive image-guided CF devices.© RSNA, 2019.