Cytotoxicity Of Dox Research Articles

Stat3/Oct-4/c-Myc signal circuit for regulating stemness-mediated doxorubicin resistance of triple-negative breast cancer cells and inhibitory effects of WP1066.

Doxorubicin (Dox) is widely used in the treatment of triple-negative breast cancer cells (TNBCs), however resistance limits its effectiveness. Cancer stem cells (CSCs) are associated with Dox resistance in MCF-7 estrogen receptor positive breast cancer cells. Signal transducer and activator of transcription3 (Stat3) may functionally shift non-CSCs towards CSCs. However, whether Stat3 drives the formation of CSCs during the development of resistance in TNBC, and whether a Stat3 inhibitor reverses CSC-mediated Dox resistance, remains to be elucidated. In the present study, human MDA-MB-468 and murine4T1 mammary carcinoma cell lines with the typical characteristics of TNBCs, were compared with estrogen receptor-positive MCF-7 cells as a model system. The MTT assay was used to detect cytotoxicity of Dox. In addition, the expression levels of CSC-specific markers and transcriptional factors were measured by western blotting, immunofluorescence staining and flow cytometry. The mammosphere formation assay wasusedto detect stem cell activity. Under long-term continuous treatment with Dox at a low concentration, TNBC cultures not only exhibited a drug-resistant phenotype, but also showed CSC properties. These Dox-resistant TNBC cells showed activation of Stat3 and high expression levels of pluripotency transcription factors octamer-binding transcription factor-4 (Oct-4) and c-Myc, which was different from the high expression of superoxide dismutase2(Sox2) in Dox-resistant MCF-7 cells. WP1066 inhibited the phosphorylation of Stat3, and decreased the expression of Oct-4 and c-Myc, leading to a reduction in the CD44-positive cell population, and restoring the sensitivity of the cells to Dox. Taken together, a novel signal circuit of Stat3/Oct-4/c-Myc was identified for regulating stemness-mediated Dox resistance in TNBC. The Stat3 inhibitor WP1066 was able to overcome the resistance to Dox through decreasing the enrichment of CSCs, highlighting the therapeutic potential of WP1066 as a novel sensitizer of Dox-resistant TNBC.

Chitosan-alginate BSA-gel-capsules for local chemotherapy against drug-resistant breast cancer.

Background and objectPolyelectrolyte microcapsule is a promising candidate for multifunctional drug delivery system. However, the lack of reports about animal experiments have greatly slowed down their development for drug delivery. We engineered biodegradable chitosan–alginate polyelectrolyte multilayer capsule filled with bovine serum albumin gel (BSA-gel-capsule). Herein, we demonstrated their applicability for local chemotherapy, a means of treating local or regional malignancies by direct administration of anti-tumor agents to tumor sites.MethodDoxorubicin (DOX) was loaded in BSA-gel-capsules and DOX-resistant cell line (MCF-7/ADR cells) was employed for antitumor studies in vitro. The cytotoxicity, cellular uptake and distribution of DOX from BSA-gel-capsules were studied. Afterwards, MCF-7/ADR xenografts tumor model was established in nude mice. The in vivo antitumor efficacy of DOX-loaded BSA-gel-capsules by intratumor injection was then evaluated.ResultCompared with free DOX, more effective cytotoxicity against MCF-7/ADR cells after treatment with DOX-loaded BSA-gel-capsules was revealed, demonstrating the positive reversal effect on drug-resistance. Thereafter, the more cellular uptake and nucleus distribution of DOX from BSA-gel-capsules in MCF-7/ADR cells provided convincing explanation for the reversal effect. DOX-loaded BSA-gel-capsules displayed remarkably more antitumor efficacy than free DOX in MCF-7/ADR cell-xenografted mice. Finally, the high DOX accumulation and prolonged retention in tumor site after local administration of DOX-loaded BSA-gel-capsules was demonstrated, displaying the unique advantages of BSA-gel-capsules for local chemotherapy.ConclusionThese findings indicate that DOX-loaded BSA-gel-capsules should be considered a potential candidate for the treatment of drug-resistant breast cancer. This paper provides a feasibility for the local chemotherapy of polyelectrolyte microcapsules, which will be a big step towards their application as drug delivery vehicles.

Doxorubicin Renal Cytotoxicity and Protection by Resveratrol (RES)

The cancer chemotherapeutic agents Doxorubicin (DOX, Adriamycin), is part of the treatment regimen for breast, Hodgkin and Non‐Hodgkin lymphomas, small cell lung cancer and acute lymphoid leukemia. Doxorubicin clinical usage is associated with cardiomyopathy and renal impairment. The mechanism for doxorubicin mediated renal toxicity has remained elusive. Resveratrol (RES) is a phytoalexin found in many fruits including grapes, blueberries, chocolate and peanuts. Antioxidant and anticancer properties have been reported for RES in cell culture and in vivo. This study tested the hypothesis that RES will reduce DOX renal cytotoxicity in human noncancerous renal proximal tubular epithelial cells (HK‐2) and that RES will attenuate DOX cytotoxicity by preserving mitochondrial function and reducing oxidative stress. HK‐2 cells were grown for 48 h. Cells were next pre‐incubated for 1 h with 0 (DMSO) or 5 or 7.5 uM RES followed by a 24 h co‐incubation with 0–5 uM DOX. All results were obtained from 3 independent experiments. Western analysis probed for protein carbonylation was used as an indicator of oxidative stress. Mitochondrial function was assessed using a Seahorse XFp system. Prior to examining mitochondrial function, cell number and substrate concentrations were optimized based on the manufacturer's recommendations. Mitochondrial Stress Test was conducted following the treatments described above and each well was normalized to protein. Western blot was conducted on whole cell lysate for SIRT1 and PGC1alpha. Viability was assessed using MTT leakage. RES did not alter cell viability as indicated by comparable MTT values between DMSO and RES groups (p>0.05). DOX was cytotoxic to HK‐2 cells within 24 h. Pretreatment with RES provided protection from DOX to HK‐2 cells. Mitochondrial respiration assessed as oxygen consumption rate (OCR) was diminished by DOX. DOX impaired mitochondria function within 24 h and RES provided protection. Further studies are needed to better characterize DOX mediated changes in mitochondria and reversal by RES.Support or Funding Information(Supported by NIH Grant P20GM103434 to the West Virginia IDeA Network for Biomedical Research Excellence).This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Effect of lutein and doxorubicin combinatorial therapy on S180 cell proliferation and tumor growth.

Multidrug resistance and toxicity significantly compromise the therapeutic efficacy for sarcomas. We aimed at evaluating the effect of lutein-doxorubicin (DOX) combinatorial therapy on inhibiting S180 (Sarcoma 180) cell proliferation and tumor growth. S180 cells in logarithmic growth phase were treated with lutein, DOX, or lutein-DOX combinatorial therapy for 48 h. The cell survival rate was determined by MTT assay. Apoptosis was detected by flow cytometry. The expression of PCNA, P53, and NF-κB was assessed by Western blot. Further, mice bearing S180 tumors received lutein, DOX, or lutein-DOX combinatorial therapy by oral gavage. Lutein-DOX combinatorial therapy significantly decreased the proliferation of S180 cells (p<0.01) in vitro. Also, the expression of proliferating cell nuclear antigen (PCNA) (p<0.05) and the apoptosis-relevant gene p53 were decreased, which resulted in increased cell apoptosis (p<0.05). The level of nuclear factor kappa B (NF-κB) was also decreased by the combinatorial therapy. Lutein-DOX combinatorial therapy reduced the cytotoxicity of DOX and reduced the inflammatory response. The inhibitory effect of lutein-DOX combinatorial therapy on cell proliferation was confirmed in vivo. The growth rate and size of the tumor at 30 d after treatment were significantly lower than those of the control group and DOX single therapy. Lutein and DOX synergistically inhibit sarcoma cell proliferation and tumor growth. This novel therapeutic regimen could potentially improve clinical outcome of sarcoma patients.

Enhancement of Cytotoxicity and Apoptosis Induction of Doxorubicin by Brazilein Containing Fraction of Secang (Caesalpinia sappan L.) on T47D Cells

Combination chemotherapy (co-chemotherapy) is a recent strategy to reduce the toxicity effect and increase the effectivity of chemotherapeutic agent, such as Doxorubicin (Dox). Caesalpinia sappan L. are potential to be developed as co-chemoterapeutic agents due to its strong cytotoxicity toward several breast cancer cells. The purpose of this research is to observe the cytotoxicity of Brazilein containing fraction (BCF) in single and its combination with doxorubicin on T47D cells. BCF was obtained by fractionation using chloroform:ethyl acetate (40:60 v/v) as mobile phase. Molecular docking results showed that Brazilein and Brazilin interacted with Bcl-2 with different binding properties. Based on MTT assay, Dox and BCF performed potent cytotoxicity with IC50 value of 403 nM and 68 μg/mL, respectively. BCF increased the cytotoxicity of Dox and performed synergism with CI value &lt;1 and decreased possible toxicity with DRI value&gt;1. Under Annexin V PI staining Flowcytometry, BCF in single and its combination with doxorubicin induced apoptosis. In conclusion, single treatment of BCF and its combination with Dox performed cytotoxic effect and induced apoptosis on T47D cell lines.Keywords: Brazilein containing fraction, Doxorubicin, Co-chemoteraphy, Apoptosis, T47D cells

Quercetin enhances chemotherapeutic effect of doxorubicin against human breast cancer cells while reducing toxic side effects of it

Doxorubicin (Dox) is an efficient drug for breast cancer chemotherapy, however, its toxic side effects on non-tumor tissues, especially on myocardial cells, sometimes limit its clinical application. Therefore, it is necessary to develop a new drug, which can be combined with Dox to potentiate the anti-tumor effect of Dox at a lower concentration and attenuate the toxic side effects of it. Quercetin (Que) has anti-tumor activity in addition to its protective effects on various cells. By preparing human non-tumoral MCF-10A mammary cells, human breast cancer MCF-7 and MDA-MB-231 cells and human myocardial AC16 cells, here, we wanted to evaluate whether Que might represent such an agent and investigate its possible mechanisms of potentiating the anti-tumor effect of Dox at a lower concentration. The results showed that Que could increase intracellular accumulation of Dox in breast cancer cells through down-regulating the expression of efflux ABC transporters including P-gp, BCRP and MRP1, which can effectively eliminate cancerous cells including breast cancer stem cells (BCSCs), thereby potentiating the anti-tumor effect of Dox. Furthermore, Que attenuated the cytotoxicity of Dox to non-tumoral MCF-10A mammary cells and myocardial AC16 cells. Therefore, Que could be used as a novel agent combined with Dox in breast cancer therapy, which could potentiate the anti-tumor effect of Dox at a lower concentration and attenuate the toxic side effects of it.

Chitosan nanoparticles triggered the induction of ROS-mediated cytoprotective autophagy in cancer cells

There is a close relationship between autophagy and apoptosis during cancer cell death. We used chitosan nanoparticles (CS NPs) to explore the effects of internalized NPs on the induction of autophagy and to confirm the role of autophagic responses elicited by nanomaterials on the tumour cell’s fate. CS NPs at nontoxic concentrations ranging from 10–100 μg/mL triggered the induction of autophagy. With the addition of CS NPs, the aggregation of endogenous LC3 was significantly enhanced and acidic autophagic bodies had been accumulated. CS NPs significantly triggered the occurrence of autophagy by increasing the ratio of LC3 II to LC3 I and CS NPs-mediated autophagy was implicated in reactive oxygen species (ROS) generation and the ROS scavenger N-acetylcysteine (NAC) attenuated CS-induced autophagy. The addition of blank NPs produced a negative effect on cytotoxicity and cellular apoptosis of free Dox, and with the pre-treatment of chloroquine (CQ) as a known autophagy inhibitor, the inhibition rates of cells treated with the combination of Dox and blank CS NPs had been significantly increased. The findings demonstrated that CS NPs have the ability to induce protective autophagy via ROS generation and they were believed to inhibit tumour cell death.

Dual-pH/Magnetic-Field-Controlled Drug Delivery Systems Based on Fe3 O4 @SiO2 -Incorporated Salecan Graft Copolymer Composite Hydrogels.

Salecan is a water-soluble extracellular β-glucan and has excellent physicochemical and biological properties for hydrogel preparation. In this study, a new pH/magnetic field dual-responsive hydrogel was prepared by the graft copolymerization of salecan with 4-pentenoic acid (PA) and N-hydroxyethylacrylamide (HEAA) in the presence of Fe3 O4 @SiO2 nanoparticles for doxorubicin hydrochloride (DOX) release. Integration of Fe3 O4 @SiO2 nanoparticles in salecan-g-poly(PA-co-HEAA) copolymers afforded magnetic sensitivity to the original material. DOX-loaded hydrogels exhibited a clear capacity for pH/magnetic field dual-responsive controlled drug release. Lowering the pH to acidic conditions or introducing an external magnetic field caused an enhancement in DOX release. This salecan-g-poly(PA-co-HEAA)/Fe3 O4 @SiO2 composite hydrogel is a promising drug carrier for magnetically targeted drug delivery with enhanced DOX cytotoxicity against A549 cells.

Doxorubicin Intracellular Remote Release from Biocompatible Oligo(ethylene glycol) Methyl Ether Methacrylate-Based Magnetic Nanogels Triggered by Magnetic Hyperthermia.

Hybrid nanogels, composed of thermoresponsive polymers and superparamagnetic nanoparticles, are attractive nanocarriers for biomedical applications, being able-as a polymer matrix-to uptake and release high quantities of chemotherapeutic agents and-as magnetic nanoparticles-to be heated when exposed to an alternative magnetic field (AMF), better known as magnetic hyperthermia. Herein, biocompatible, pH-responsive, magnetoresponsive, and thermoresponsive nanogels, based on oligo(ethylene glycol) methyl ether methacrylate monomers and a methacrylic acid comonomer were prepared by conventional precipitation radical copolymerization in water, post-assembled by complexation with iron oxide magnetic nanoparticles (MNPs) of maghemite (γ-Fe2O3), and loaded with an anticancer drug (doxorubicin, DOX), for remotely controlled drug release by a "hot spot", as an athermal magnetic hyperthermia strategy against cancer. These nanogels, denoted MagNanoGels, with a hydrodynamic diameter from 328 to 460 nm, as a function of the MNP content, have a swelling-deswelling behavior at their volume phase temperature transition around 47 °C in a physiological medium (pH 7.5), which is above the human body temperature (37 °C). Applying an alternative magnetic field increases the release of DOX by 2-fold, while no macroscopic heating was recorded. This enhanced drug release is due to a shrinking of the polymer network by local heating, as illustrated by the MagNanoGel size decrease under an AMF. In cancer cells, not only do the DOX-MagNanoGels internalize DOX more efficiently than free DOX, but also DOX intracellular release can be remotely triggered under an AMF, in athermal conditions, thus enhancing DOX cytotoxicity.

Folate/N-acetyl glucosamine conjugated mesoporous silica nanoparticles for targeting breast cancer cells: A comparative study

Folate receptors (FR) have been well recognized as a marker to target nano-sized carriers for cancer diagnosis and therapy. In contrast, influx transport systems (e.g. GLUT transporters) that transport essential amino acids and nutrients to cancer cells have not been exploited much for targeted delivery. In this study, folic acid- or n-acetyl glucosamine- functionalized mesoporous silica nanoparticles loaded with doxorubicin (DOX-FA-MSNPs or DOX-NAG-MSNPs) were prepared, characterized and compared for targeting along with cytotoxicity towards MCF-7 and MDA-MB-231 human breast cancer cells. Cellular uptake of FITC tagged FA-MSNPs and NAG-MSNPs were evaluated by confocal microscopy and flow cytometry in above-mentioned cancer cell lines. The result suggested higher cellular uptake of NAG-MSNPs than FA-MSNPs for both the cell lines. Cytotoxicity of free DOX, DOX-MSNPs, DOX-FA-MSNPs and DOX-NAG-MSNPs were evaluated on both the breast cancer cell lines. Cytotoxicity results showed that DOX-loaded NAG-MSNPs exerted significant higher cytotoxicity effect on both the cell lines than DOX-FA-MSNPs. Moreover, both the targeted formulations were more effective than free DOX. Our results suggested that GLUT transporters can be effectively utilized for nanoparticles internalization in breast cancer cells.

Exceptional release kinetics and cytotoxic selectivity of oxidised MWCNTs double-functionalised with doxorubicin and prostate-homing peptide

Multiwall carbon nanotubes (MWCNTs) are among the frequently studied carbon materials, particularly because of their physical and chemical properties and high potential for application in materials chemistry, industry, and medicine. MWCNTs are very promising as transporters of bioactive molecules because of their π electrons and large surface area, which can be easily modified, mostly by the application of inorganic acids for the introduction of carboxylic moieties on the surface. In the present study, we designed an oxidised MWCNTs (oMWCNTs) transporter for the targeted delivery of doxorubicin (Dox). The modification of oMWCNTs with prostate-homing peptide (SMSIARL) promotes increased cytotoxicity for prostate cancer cells. Using advanced analytical techniques, we studied the loading efficiency, stability, and release kinetics of Dox from a oMWCNTs-Dox-Pep nanoconstruct. We show that pH strictly drives Dox release, and imitating the pH of intracellular acidic compartments, 60% of Dox is released from oMWCNTs-Dox-Pep, while in plasma conditions, only a 14% release of Dox was found during 24h. The nanoconstruct displayed no cytotoxicity in non-malignant prostate cells (PNT1A), while in metastatic prostate cancer cells (LNCaP), the cytotoxic effects were close to the cytotoxicity of free Dox. This indicates that peptide modification promotes interactions with malignant cells, resulting in efficient internalisation into the intracellular region. Overall, we show that oMWCNTs are exceptional platforms for simple and stable non-covalent modification with bioactive molecules.

Doxorubicin and paclitaxel co-bound lactosylated albumin nanoparticles having targetability to hepatocellular carcinoma

Anticancer drug targeting to liver asialoglycoprotein receptors (ASGPR) is viewed as a good approach for hepatocellular carcinoma (HCC) treatment. Lactose residue is a promising ASGPR ligand due to its high receptor affinity. Herein, we introduce doxorubicin and paclitaxel co-bound lactosylated albumin (Lac-BSA) nanoparticles (Dox/Pac Lac-BSA NPs) with good liver targetability. Lac-BSA was synthesized by conjugating lactobionic acid to naïve BSA then characterized by mass spectrometry. Dox/Pac Lac-BSA NPs were fabricated utilizing high-pressure homogenization and evaporation with Nab® (nanoparticle albumin bound) technology. Dox/Pac Lac-BSA NPs were spherical and well-dispersed, with a 148.7±13.8nm particle size and −54.1±0.7mV zeta potential at a 100% Lac-BSA feed ratio. Combined Dox and Pac synergistic cytotoxicity was confirmed in Hep G2 cells. Specifically, the inhibitory concentration (IC50; 0.21±0.02μg/ml) for Dox/Pac Lac-BSA NPs was 3.2 time lower than plain Dox/Pac BSA NPs (IC50; 0.68±0.04μg/ml). Also, Dox/Pac Lac-BSA NPs exhibited better internalizing in Hep G2 cells (61.8% vs. 14.4% for Dox) and spheroids compared to Dox/Pac BSA NPs. Finally, Dox/Pac Lac-BSA NPs displayed much greater localization into ICR mice livers compared to Dox/Pac BSA NPs. This was indicated by the presence of NP lactose residues revealed by a galactose inhibition study. Based on these results, we suggest that lactose-modified albumin-based nanoparticles fabricated with the Nab® technique can be a potential therapeutic vector for treating HCC via hepatocyte targeting.

Development of Doxorubicin-Loaded Nanostructured Lipid Carriers: Preparation, Characterization, and In Vitro Evaluation on MCF-7 Cell Line

Nanostructured lipid carriers (NLC) are produced using a blend of solid and liquid lipids; this blend is solid at room temperature. NLC is a second generation of lipid nanoparticles, which offer the advantage of improved drug-loading capability and release properties. The purpose of this study was to find the optimized proportion of liquid and solid lipids for production of doxorubicin (Dox)-loaded NLC (Dox-NLC) to decrease the cytotoxicity of Dox. Dox-NLC was prepared by the solvent emulsification/evaporation method using stearic acid (SA) and oleic acid (OA) as the solid lipid and liquid lipid, respectively. Poloxamer 188 and lecithin were used to stabilize NLC dispersion. The physicochemical characteristic and cytotoxicity of Dox-NLC were evaluated. The NLC prepared by 0.6% of stearic acid and 0.4% of oleic acid, showed optimum results with particle size of 134.0 ± 2.3 nm, zeta potential of −19.0 ± 3.9 mV, drug-loading efficiency of 9.5%, and entrapment efficiency of 75%. The drug loading after freeze drying and also after 60 days storage at 4 °C did not change. In vitro drug release study showed that Dox was released from the NLC in a slow but time-dependent behavior. The cytotoxicity of Dox-NLC on MCF-7 cell line was increased compared with the Dox solution. These results suggested that the Dox-NLC produced by this method could be utilized as a sustained release drug carrier system for improving the effectiveness of chemotherapy.

An in vitro demonstration of overcoming drug resistance in SKOV3 TR and MCF7 ADR with targeted delivery of polymer pro-drug conjugates

Drug resistance is a common phenomenon that occurs in cancer chemotherapy. Delivery of chemotherapeutic agents as polymer pro-drug conjugates (PPDCs) pretargeted with bispecific antibodies could circumvent drug resistance in cancer cells. To demonstrate this approach to overcome drug resistance, Paclitaxel (Ptxl)-resistant SKOV3 TR human ovarian- and doxorubicin (Dox)-resistant MCF7 ADR human mammary-carcinoma cell lines were used. Pre-targeting over-expressed biotin or HER2/neu receptors on cancer cells was conducted by biotinylated anti-DTPA or anti-HER2/neu affibody – anti-DTPA Fab bispecific antibody complexes. The targeting PPDCs are either D-Dox-PGA or D-Ptxl-PGA. Cytotoxicity studies demonstrate that the pretargeted approach increases cytotoxicity of Ptxl or Dox in SKOV3 TR or MCF7 ADR resistant cell lines by 5.4 and 27 times, respectively. Epifluorescent microscopy – used to track internalization of D-Dox-PGA and Dox in MCF7 ADR cells – shows that the pretargeted delivery of D-Dox-PGA resulted in a 2- to 4-fold increase in intracellular Dox concentration relative to treatment with free Dox. The mechanism of internalization of PPDCs is consistent with endocytosis. Enhanced drug delivery and intracellular retention following pretargeted delivery of PPDCs resulted in greater tumor cell toxicity in the current in vitro studies.

A Novel Approach on Drug Delivery: Investigation of A New Nano-Formulation of Liposomal Doxorubicin and Biological Evaluation of Entrapped Doxorubicin on Various Osteosarcoma Cell Lines.

Objective In this study we prepared a novel formulation of liposomal doxorubicin (L- DOX). The drug dose was optimized by analyses of cellular uptake and cell viability of osteosarcoma (OS) cell lines upon exposure to nanoliposomes that contained varying DOX concentrations. We intended to reduce the cytotoxicity of DOX and improve characteristics of the nanosystems. Materials and Methods In this experimental study, we prepared liposomes by the pH gradient hydration method. Various characterization tests that included dynamic light scattering (DLS), cryogenic transmission electron microscopy (Cryo-TEM) imaging, and UV- Vis spectrophotometry were employed to evaluate the quality of the nanocarriers. In addition, the CyQUANT® assay and fluorescence microscope imaging were used on various OS cell lines (MG-63, U2-OS, SaOS-2, SaOS-LM7) and Human primary osteoblasts cells, as novel methods to determine cell viability and in vitro transfection efficacy. Results We observed an entrapment efficiency of 84% for DOX within the optimized liposomal formulation (L-DOX) that had a liposomal diameter of 96 nm. Less than 37% of DOX released after 48 hours and L-DOX could be stored stably for 14 days. L-DOX increased DOX toxicity by 1.8-4.6 times for the OS cell lines and only 1.3 times for Human primary osteoblasts cells compared to free DOX, which confirmed a higher sensitivity of the OS cell lines versus Human primary osteoblasts cells for L-DOX. We deduced that L- DOX passed more freely through the cell membrane compared to free DOX. ConclusionWe successfully synthesized a stealth L-DOX that contained natural phospholipid by the pH gradient method, which could encapsulate DOX with 84% efficiency. The resulting nanoparticles were round, with a suitable particle size, and stable for 14 days. These nanoparticles allowed for adequately controlled DOX release, increased cell permeability compared to free DOX, and increased tumor cell death. L-DOX provided a novel, more effective therapy for OS treatment.

Development of novel self-assembled ES-PLGA hybrid nanoparticles for improving oral absorption of doxorubicin hydrochloride by P-gp inhibition: In vitro and in vivo evaluation

To increase the encapsulation efficiency and oral absorption of doxorubicin hydrochloride (DOX), a novel drug delivery system of enoxaparin sodium-PLGA hybrid nanoparticles (EPNs) was successfully designed. By introducing the negative polymer of enoxaparin sodium (ES) to form an electrostatic complex with the cationic drug, DOX, the encapsulation efficiency (93.78%) of DOX was significantly improved. The X-ray diffraction (XRD) results revealed that the DOX-ES complex was in an amorphous form. An in vitro release (pH6.8 PBS) study showed the excellent sustained-release characteristics of DOX-loaded EPNs (DOX-EPNs). In addition, in situ intestinal perfusion and intestinal biodistribution experiments demonstrated the improved membrane permeability and intestinal wall bioadhesion of DOX-EPNs, and caveolin- and clathrin-mediated endocytosis pathways were the main mechanisms responsible. The cytotoxicity of DOX was significantly increased by EPNs in Caco-2 cells, compared with DOX-Sol. Confocal laser scanning microscope (CLSM) images confirmed that the amount of DOX-EPNs internalized by Caco-2 cells was higher than that of DOX-Sol showing that P-glycoprotein-mediated drug efflux was reduced by the introduction of EPNs. The qualitative detection of transcytosis demonstrated the ability of the nanoparticles (NPs) to cross Caco-2 cell monolayers. An in vivo toxicity experiment demonstrated that DOX-EPNs reduced cardiac and renal toxic effects and were biocompatible. An in vivo pharmacokinetics study showed that the AUC(0-t) and t1/2 of DOX-EPNs were increased to 3.63–fold and 2.47–fold in comparison with DOX solution (DOX-Sol), respectively. All these results indicated that the novel EPNs were an excellent platform to improve the encapsulation efficiency of an aqueous solution of this antitumor drug and its oral bioavailability.

Fabrication of self-assembled chitosan-dispersed LDL nanoparticles for drug delivery with a one-step green method

Self-assembled nanoparticles (NPs) composed of chitosan (CS) and low density lipoprotein (LDL) of hen eggs were prepared by a one-step green synthesis of mixing CS solution and LDL suspension. The formulated CS-LDL NPs were then applied to encapsulate doxorubicin hydrochloride (DOX) with the encapsulation efficiency of 51.7%. The average particle size and ζ-potential of DOX-loaded CS-LDL NPs (CS-LDL-DOX NPs) were 179nm and +48.3mV, respectively. The encapsulated DOX showed less cytotoxicity than free DOX after 24-h incubation with gastric cancer SGC7901 cells, which may be due to extended release. Cellular uptake of CS-LDL-DOX NPs was significant higher than that of free DOX due to the endocytosis of tumor cells. Thus CS-LDL-DOX NPs showed a potential in reducing cytotoxicity of DOX by extended release behavior and preferential uptake compared to free DOX. In addition, flow cytometry and terminal-deoxynucleotidyl-transferase-mediated dUTP nick-end labeling assay demonstrated that CS-LDL-DOX NPs induced the apoptosis of cancer cells. Autophagy was involved in effects caused by CS-LDL-DOX NPs through blocking AKT/mTOR signaling, which was demonstrated by the analyses of the expression of LC3, p62, AKT, p-AKT, mTOR and p-mTOR.

Monitoring Tumor Response after Liposomal Doxorubicin in Combination with Liposomal Vinorelbine Treatment Using 3'-Deoxy-3'-[18F]Fluorothymidine PET.

Surgical resection is the standard treatment for localized colorectal cancer, which is the most common type of gastrointestinal cancer. However, over 40% cases are diagnosed metastasized and apparently inoperable. Systemic chemotherapy provides an alternative to these patients. This study aims to evaluate the therapeutic potential of liposomal doxorubicin (lipoDox) in combination with liposomal vinorelbine (lipoVNB) in a CT-26 colon carcinoma-bearing mouse model. The in vitro cytotoxicity of Dox and VNB on CT-26 cancer cells was determined by MTT and colony formation assays. Mice were subcutaneously inoculated with 2×105 of CT-26 cells in the right hind flank. When tumor size reached 200±50mm3, mice were assigned to receive different treatment protocols. The pharmacokinetics, micro single-photon emission computed tomography/x-ray computed tomography imaging, biodistribution, and immunohistochemical staining studies were performed to survey the therapeutic efficacy of each regimen. Based on the results of pharmacokinetic study, co-administration of lipoDox and lipoVNB did not affect their individual systemic distribution, while lipoDox retained longer in blood than lipoVNB did. Superior tumor growth retardation was observed in the group received lipoDox plus lipoVNB administration (1mg/kg each, namely D1V1) than those injected with lipoDox plus VNB (1mg/kg each, namely D1fV1). No severe side effects were detected in each group. The tumor-to-muscle ratio (T/M) derived from 3'-dexoy-3'-[18F]fluorothymidine ([18F]FLT) micro positron emission tomography (PET) images of D1V1- and D1fV1-treated mice and the controls on day 7 was 6.88±0.54, 7.50±0.84, and 9.87±0.73, respectively, suggesting that D1V1 is a more efficacious regimen against CT-26 xenografts. The results of proliferating cell nuclear antigen (PCNA) immunohistochemical staining were consistent with those findings obtained from [18F]FLT microPET imaging. This study demonstrated that lipoDox in combination with lipoVNB was more efficacious than clinically used regimen, lipoDox plus VNB, in the treatment of colon carcinoma and [18F]FLT-PET is a promising approach in monitoring the treatment outcome at early stage.

Localized sequence-specific release of a chemopreventive agent and an anticancer drug in a time-controllable manner to enhance therapeutic efficacy.

Combination chemotherapy with multiple drugs commonly requires several injections on various schedules, and the probability that the drug molecules reach the diseased tissues at the proper time and effective therapeutic concentrations is very low. This work elucidates an injectable co-delivery system that is based on cationic liposomes that are adsorbed on anionic hollow microspheres (Lipos-HMs) via electrostatic interaction, from which the localized sequence-specific release of a chemopreventive agent (1,25(OH)2D3) and an anticancer drug (doxorubicin; DOX) can be thermally driven in a time-controllable manner by an externally applied high-frequency magnetic field (HFMF). Lipos-HMs can greatly promote the accumulation of reactive oxygen species (ROS) in tumor cells by reducing their cytoplasmic expression of an antioxidant enzyme (superoxide dismutase) by 1,25(OH)2D3, increasing the susceptibility of cancer cells to the cytotoxic action of DOX. In nude mice that bear xenograft tumors, treatment with Lipos-HMs under exposure to HFMF effectively inhibits tumor growth and is the most effective therapeutic intervention among all the investigated. These empirical results demonstrate that the synergistic anticancer effects of sequential release of 1,25(OH)2D3 and DOX from the Lipos-HMs may have potential for maximizing DOX cytotoxicity, supporting more effective cancer treatment.

Nanogels fabricated from bovine serum albumin and chitosan via self-assembly for delivery of anticancer drug

In this study, bovine serum albumin (BSA) and chitosan (CS) were used to prepare BSA-CS nanogels by a simple green self-assembly technique. Then the nanogels were successfully used to entrap doxorubicin hydrochloride (DOX) with an entrapment ratio of 46.3%, aiming to realize the slow-release effect and lower the cytotoxicity of DOX. The IC50 values of DOX-loaded BSA-CS (DOX-BSA-CS) and free DOX obtained by MTT assay in SGC7901 cells were 0.22 and 0.05μg/mL, respectively. The cytotoxicity of DOX significantly decreased within 24h after encapsulation by the nanogels, indicating that the loaded drug could slowly release within 24h and the BSA-CS was a good slow release system. The cellular uptake experiments indicated DOX-BSA-CS diffused faster into the cancer cell than the bare drug. The flow cytometry and TUNEL assay proved DOX-BSA-CS could induce a larger apoptosis proportion of gastric cancer cells 7901 than the bare drug and it is promising to be used for curing gastric cancer.