Folate receptor targeted, carboxymethyl chitosan functionalized iron oxide nanoparticles: a novel ultradispersed nanoconjugates for bimodal imaging

This article delineates the design and synthesis of a novel, bio-functionalized, magneto-fluorescent multifunctional nanoparticles suitable for cancer-specific targeting, detection and imaging. Biocompatible, hydrophilic, magneto-fluorescent nanoparticles with surface-pendant amine, carboxyl and aldehyde groups were designed using o-carboxymethyl chitosan (OCMC). The free amine groups of OCMC stabilized magnetite nanoparticles on the surface allow for the covalent attachment of a fluorescent dye such as rhodamine isothiocyanate (RITC) with the aim to develop a magneto-fluorescent nanoprobe for optical imaging. In order to impart specific cancer cell targeting properties, folic acid and its aminated derivative was conjugated onto these magneto-fluorescent nanoparticles using different pendant groups (-NH(2), -COOH, -CHO). These newly synthesized iron-oxide folate nanoconjugates (FA-RITC-OCMC-SPIONs) showed excellent dispersibility, biocompatibility and good hydrodynamic sizes under physiological conditions which were extensively studied by a variety of complementary techniques. The cellular internalization efficacy of these folate-targeted and its non-targeted counterparts were studied using a folate-overexpressed (HeLa) and a normal (L929 fibroblast) cells by fluorescence microscopy and magnetically activated cell sorting (MACS). Cell-uptake behaviors of nanoparticles clearly demonstrate that cancer cells over-expressing the human folate receptor internalized a higher level of these nanoparticle-folate conjugates than normal cells. These folate targeted nanoparticles possess specific magnetic properties in the presence of an external magnetic field and the potential of these nanoconjugates as T(2)-weighted negative contrast MR imaging agent were evaluated in folate-overexpressed HeLa and normal L929 fibroblast cells.     

Preparation and functional study of pH-sensitive amorphous calcium phosphate nanocarriers

Recently, multifunctional nanoparticles have shown great prospects in cancer treatment, which have the ability to simultaneously deliver the drug, image and target tumor cells. In this paper, we designed a luminescent nanoparticles platform based on hydrothermal hyaluronic acid/amorphous calcium phosphate (HA-FCNs/ACP) with multifunctional properties for drug delivery, bio-imaging, and targeting treatment. HA-FCNs/ACP shows an ability to load curcumin (Cur) with pH-sensitive responsive drug release behavior and excellent biocompatibility. HA-FCNs/ACP dispersed in the cytoplasm through the overexpressed CD44 receptor that is actively targeted into human lung cancer cells (A549 cells). Meanwhile, the viability of A549 cells was significantly inhibited in vitro. The prepared HA-FCNs and HA-FCNs/ACP both exhibit excellent targeted bioimaging performance on cancer cells. Hence, the as-prepared nanoparticles have promising applications in treating tumor disease.     

A RNA-DNA Hybrid Aptamer for Nanoparticle-Based Prostate Tumor Targeted Drug Delivery

The side effects of radio- and chemo-therapy pose long-term challenges on a cancer patient’s health. It is, therefore, highly desirable to develop more effective therapies that can specifically target carcinoma cells without damaging normal and healthy cells. Tremendous efforts have been made in the past to develop targeted drug delivery systems for solid cancer treatment. In this study, a new aptamer, A10-3-J1, which recognizes the extracellular domain of the prostate specific membrane antigen (PSMA), was designed. A super paramagnetic iron oxide nanoparticle-aptamer-doxorubicin (SPIO-Apt-Dox) was fabricated and employed as a targeted drug delivery platform for cancer therapy. This DNA RNA hybridized aptamer antitumor agent was able to enhance the cytotoxicity of targeted cells while minimizing collateral damage to non-targeted cells. This SPIO-Apt-Dox nanoparticle has specificity to PSMA⁺ prostate cancer cells. Aptamer inhibited nonspecific uptake of membrane-permeable doxorubic to the non-target cells, leading to reduced untargeted cytotoxicity and endocytic uptake while enhancing targeted cytotoxicity and endocytic uptake. The experimental results indicate that the drug delivery platform can yield statistically significant effectiveness being more cytotoxic to the targeted cells as opposed to the non-targeted cells.     

LHRH-PE40对LOVO细胞的靶向杀伤作用

目的研究LHRH-PE40对LOVO细胞的靶向杀伤作用。方法用XTT检测LHRH-PE40对LOVO细胞的体外细胞毒性。将LOVO细胞移植于裸鼠,测定静脉注射LHRH-PE40对体内肿瘤细胞生长的抑制作用。结果LHRH-PE40对LOVO细胞细胞毒作用的半数抑制浓度为2·103μg/ml,在裸鼠肿瘤模型中,LHRH-PE40剂量为150μg/kg时抑瘤率为68·49%,这种细胞毒性作用可以被LHRH(或LHRH类似物)特异性抑制。结论在体内外LHRH-PE40对LOVO细胞具有很强的细胞毒作用,其机制是LHRH-PE40通过与癌细胞膜上的LHRH受体特异结合发挥细胞杀伤作用。     

LHRH-PE40与癌细胞表面LHRH受体结合特性的检测

目的检测LHRH-PE40融合蛋白是否保留了LHRH与癌细胞表面其相应受体特异性结合的性质。方法在Hela细胞培养液中,分别加入LHRH和LHRHPE40,经结晶紫染色法检测A值。另取宫颈癌组织切片,分别加LHRH-PE40和LHRH后,再加兔抗PE40血清和羊抗兔IgG异硫氰酸荧光素,在荧光显微镜下观察荧光强度。结果随着LHRH与LHRHPE40的摩尔数之比由100/1、250/1增加到500/1,细胞毒性的效果逐渐减弱。当LHRH/LHRH-PE40达到500/1时,肿瘤细胞表面的LHRH受体饱和;LHRH/LHRHPE40达750/1时,其A值与500/1时的A值接近。宫颈癌组织加入LHRH竞争后,荧光强度较仅加LHRHPE40组明显减弱。结论重组毒素LHRH-PE40仍保留了与癌细胞LHRH受体结合的特性。     

Development and Screening of a Series of Antibody‐Conjugated and Silica‐Coated Iron Oxide Nanoparticles for Targeting the Prostate‐Specific Membrane Antigen

The prostate‐specific membrane antigen (PSMA) is an established target for the delivery of cancer therapeutic and imaging agents due to its high expression on the surface of prostate cancer cells and within the neovasculature of other solid tumors. Here, we describe the synthesis and screening of antibody‐conjugated silica‐coated iron oxide nanoparticles for PSMA‐specific cell targeting. The humanized anti‐PSMA antibody, HuJ591, was conjugated to a series of nanoparticles with varying densities of polyethylene glycol and primary amine groups. Customized assays utilizing iron spectral absorbance and enzyme‐linked immunoassay (ELISA) were developed to screen microgram quantities of nanoparticle formulations for immunoreactivity and cell targeting ability. Antibody and PSMA‐specific targeting of the optimized nanoparticle was evaluated using an isogenic PSMA‐positive and PSMA‐negative cell line pair. Specific nanoparticle targeting was confirmed by iron quantification with inductively coupled plasma mass spectrometry (ICP‐MS). These methods and nanoparticles support the promise of targeted theranostic agents for future treatment of prostate and other cancers.     

Galactosylated Chitosan Oligosaccharide Nanoparticles for Hepatocellular Carcinoma Cell-Targeted Delivery of Adenosine Triphosphate

Nanoparticles composed of galactosylated chitosan oligosaccharide (Gal-CSO) and adenosine triphosphate (ATP) were prepared for hepatocellular carcinoma cell-specific uptake, and the characteristics of Gal-CSO/ATP nanoparticles were evaluated. CSO/ATP nanoparticles were prepared as a control. The average diameter and zeta potential of Gal-CSO/ATP nanoparticles were 51.03 ± 3.26 nm and 30.50 ± 1.25 mV, respectively, suggesting suitable properties for a drug delivery system. Subsequently, the cytotoxicity of Gal-CSO/ATP nanoparticles were examined by the methyl tetrazolium (MTT) assay, and the half maximal inhibitory concentration (IC₅₀) values were calculated with HepG2 (human hepatocellular carcinoma cell line) cells. The results showed that the cytotoxic effect of nanoparticles on HepG2 cells was low. In the meantime, it was also found that the Gal-CSO/ATP nanoparticles could be uptaken by HepG2 cells, due to expression of the asialoglycoprotein receptor (ASGP-R) on their surfaces. The presented results indicate that the Gal-CSO nanoparticles might be very attractive to be used as an intracellular drug delivery carrier for hepatocellular carcinoma cell targeting, thus warranting further in vivo or clinical investigations.     

Targeted Delivery Systems for Molecular Therapy in Skeletal Disorders

Abnormalities in the integral components of bone, including bone matrix, bone mineral and bone cells, give rise to complex disturbances of skeletal development, growth and homeostasis. Non-specific drug delivery using high-dose systemic administration may decrease therapeutic efficacy of drugs and increase the risk of toxic effects in non-skeletal tissues, which remain clinical challenges in the treatment of skeletal disorders. Thus, targeted delivery systems are urgently needed to achieve higher drug delivery efficiency, improve therapeutic efficacy in the targeted cells/tissues, and minimize toxicities in non-targeted cells/tissues. In this review, we summarize recent progress in the application of different targeting moieties and nanoparticles for targeted drug delivery in skeletal disorders, and also discuss the advantages, challenges and perspectives in their clinical translation.     

Doxorubicin loaded silica nanorattles actively seek tumors with improved anti-tumor effects

Silica nanorattles (SNs) have proven to be promising vehicles for drug delivery. In order to further enhance efficacy and minimize adverse effects, active targeted delivery to tumors is necessary. In this work, SNs modified with a tumor specific targeting ligand, folic acid (FA), was used as carrier of doxorubicin (DOX) (DOX-FA-SNs). Drug loading, cytotoxicity and cellular uptake of DOX-FA-SNs in vitro in human cervical carcinoma cells (HeLa cells) were evaluated. DOX-FA-SNs showed a higher cytotoxicity in human cervical carcinoma cells (HeLa cells) than DOX loaded carboxyl (-COOH) and poly(ethylene glycol) (PEG) modified SNs (DOX-COOH-SNs and DOX-PEG-SNs, respectively). However, DOX-FA-SNs showed lower cytotoxicity in folate receptor negative normal mouse fibroblast cells (L929 cells) compared with free DOX. In vivo tumor-targeted fluorescence imaging indicated specific tumor targeting and uptake of FA-SNs in nude mice bearing subcutaneous HeLa cell-derived xenograft tumors. In vivo anti-tumor experiments demonstrated that DOX-FA-SNs (10 mg kg(-1) of DOX) significantly regressed the tumor growth and reduced toxicity compared with free DOX. These results have great significance in developing and optimizing SNs as effective intracellular delivery and specific tumor targeting vehicles.     

HAI-178 antibody-conjugated fluorescent magnetic nanoparticles for targeted imaging and simultaneous therapy of gastric cancer

The successful development of safe and highly effective nanoprobes for targeted imaging and simultaneous therapy of in vivo gastric cancer is a great challenge. Herein we reported for the first time that anti-α-subunit of ATP synthase antibody, HAI-178 monoclonal antibody-conjugated fluorescent magnetic nanoparticles, was successfully used for targeted imaging and simultaneous therapy of in vivo gastric cancer. A total of 172 specimens of gastric cancer tissues were collected, and the expression of α-subunit of ATP synthase in gastric cancer tissues was investigated by immunohistochemistry method. Fluorescent magnetic nanoparticles were prepared and conjugated with HAI-178 monoclonal antibody, and the resultant HAI-178 antibody-conjugated fluorescent magnetic nanoparticles (HAI-178-FMNPs) were co-incubated with gastric cancer MGC803 cells and gastric mucous GES-1 cells. Gastric cancer-bearing nude mice models were established, were injected with prepared HAI-178-FMNPs via tail vein, and were imaged by magnetic resonance imaging and small animal fluorescent imaging system. The results showed that the α-subunit of ATP synthase exhibited high expression in 94.7% of the gastric cancer tissues. The prepared HAI-178-FMNPs could target actively MGC803 cells, realized fluorescent imaging and magnetic resonance imaging of in vivo gastric cancer, and actively inhibited growth of gastric cancer cells. In conclusion, HAI-178 antibody-conjugated fluorescent magnetic nanoparticles have a great potential in applications such as targeted imaging and simultaneous therapy of in vivo early gastric cancer cells in the near future.     

The Photodynamic Effect of Different Size ZnO Nanoparticles on Cancer Cell Proliferation In Vitro

Nanomaterials have widely been used in the field of biological and biomedicine, such as tissue imaging, diagnosis and cancer therapy. In this study, we explored the cytotoxicity and photodynamic effect of different-sized ZnO nanoparticles to target cells. Our observations demonstrated that ZnO nanoparticles exerted dose-dependent and time-dependent cytotoxicity for cancer cells like hepatocellular carcinoma SMMC-7721 cells in vitro. Meanwhile, it was observed that UV irradiation could enhance the suppression ability of ZnO nanoparticles on cancer cells proliferation, and these effects were in the size-dependent manner. Furthermore, when ZnO nanoparticles combined with daunorubicin, the related cytotoxicity of anticancer agents on cancer cells was evidently enhanced, suggesting that ZnO nanoparticles could play an important role in drug delivery. This may offer the possibility of the great potential and promising applications of the ZnO nanoparticles in clinical and biomedical areas like photodynamic cancer therapy and others.     

Nanoparticles of Poly(Lactide-Co-Glycolide)-d-a-Tocopheryl Polyethylene Glycol 1000 Succinate Random Copolymer for Cancer Treatment

Cancer is the leading cause of death worldwide. Nanomaterials and nanotechnologies could provide potential solutions. In this research, a novel biodegradable poly(lactide-co-glycolide)-d-a-tocopheryl polyethylene glycol 1000 succinate (PLGA-TPGS) random copolymer was synthesized from lactide, glycolide and d-a-tocopheryl polyethylene glycol 1000 succinate (TPGS) by ring-opening polymerization using stannous octoate as catalyst. The obtained random copolymers were characterized by ¹H NMR, FTIR, GPC and TGA. The docetaxel-loaded nanoparticles made of PLGA-TPGS copolymer were prepared by a modified solvent extraction/evaporation method. The nanoparticles were then characterized by various state-of-the-art techniques. The results revealed that the size of PLGA-TPGS nanoparticles was around 250 nm. The docetaxel-loaded PLGA-TPGS nanoparticles could achieve much faster drug release in comparison with PLGA nanoparticles. In vitro cellular uptakes of such nanoparticles were investigated by CLSM, demonstrating the fluorescence PLGA-TPGS nanoparticles could be internalized by human cervix carcinoma cells (HeLa). The results also indicated that PLGA-TPGS-based nanoparticles were biocompatible, and the docetaxel-loaded PLGA-TPGS nanoparticles had significant cytotoxicity against Hela cells. The cytotoxicity against HeLa cells for PLGA-TPGS nanoparticles was in time- and concentration-dependent manner. In conclusion, PLGA-TPGS random copolymer could be acted as a novel and promising biocompatible polymeric matrix material applicable to nanoparticle-based drug delivery system for cancer chemotherapy.     

Microfluidic fabrication of cationic curcumin nanoparticles as an anti-cancer agent

Curcumin nanoparticles of less than 50 nm in diameter are accessible using a continuous flow microfluidic rotating tube processor (RTP) under scalable conditions, at room temperature. A mixture of DDAB and Pluronic F127 renders higher stability of the curcumin nanoparticles in physiological pH 7.4 for up to eight hours. The nanoparticles have enhanced cytotoxicity in estrogens receptor negative and positive breast cancer cell lines compared with free curcumin.     

Controlled release of curcumin from thiolated starch-coated iron oxide magnetic nanoparticles: An in vitro evaluation

Thiolated starch-coated iron oxide nanoparticles containing curcumin were developed to investigate their cytotoxicity on lymphocytes and cancer cell lines. These nanoparticles were prepared using different concentrations of thiolated starch to study the effect of polymer coating on various properties of nanoparticles, namely, yield percentage, particle size, drug encapsulation, etc. Zeta potential confirmed the stability of nanoparticles. The nanoparticles with 5% polymer coating showed drug encapsulation efficiency up to 78%, while loading efficiency was higher than 80%. The cytotoxicity assay revealed excellent compatibility of the system with lymphocyte cells while considerable amount of cytotoxicity on cancer cell lines.     

Water-soluble heparin-PTX conjugates for cancer targeting

Targeted drug delivery to cancer cells or tumor vasculature is an attractive approach to treating cancer. We here report the synthesis of an anticancer drug conjugate composed of paclitaxel (PTX) and polysaccharide heparin through the reaction of aminated PTX with the carboxyl group of heparin. The structure of the conjugates was identified by ¹H NMR and FT-IR measurements. Heparin-PTX conjugates have high solubility in aqueous solutions. Unlike physically encapsulated drugs, heparin-PTX can self-assemble to form spherical nanoparticles in aqueous solution as characterized by Transmission Electron Microscopy (TEM). Size distribution of the nanoparticles as determined by Dynamic Light Scattering (DLS) was in the range of 200-400 nm depending on the coupling ratio of PTX to heparin molecules. The anticoagulant activity of heparin-PTX conjugates was decreased compared to that of heparin, thereby reducing hemorrhagic side effects. Cellular uptake of the nanoparticles was significantly enhanced compared to heparin as visualized by Confocal Laser Scanning Microscopy (CLSM). Furthermore, heparin-PTX conjugate nanoparticles exhibited higher cytotoxicity against KB cancer cells than did free PTX. The cytotoxicity of nanoparticles was found to depend on the amount of PTX conjugated to heparin as well as the conjugate concentration. Thus, conjugation of PTX to heparin may be useful for the solubilization and targeted delivery of PTX to solid tumors.     

Thiolated chitosan-modified PLA-PCL-TPGS nanoparticles for oral chemotherapy of lung cancer

Oral chemotherapy is a key step towards ‘chemotherapy at home’, a dream of cancer patients, which will radically change the clinical practice of chemotherapy and greatly improve the quality of life of the patients. In this research, three types of nanoparticle formulation from commercial PCL and self-synthesized d-α-tocopheryl polyethylene glycol 1000 succinate (PLA-PCL-TPGS) random copolymer were prepared in this research for oral delivery of antitumor agents, including thiolated chitosan-modified PCL nanoparticles, unmodified PLA-PCL-TPGS nanoparticles, and thiolated chitosan-modified PLA-PCL-TPGS nanoparticles. Firstly, the PLA-PCL-TPGS random copolymer was synthesized and characterized. Thiolated chitosan greatly increases its mucoadhesiveness and permeation properties, thus increasing the chances of nanoparticle uptake by the gastrointestinal mucosa and improving drug absorption. The PLA-PCL-TPGS nanoparticles were found by FESEM that they are of spherical shape and around 200 nm in diameter. The surface charge of PLA-PCL-TPGS nanoparticles was reversed from anionic to cationic after thiolated chitosan modification. The thiolated chitosan-modified PLA-PCL-TPGS nanoparticles have significantly higher level of the cell uptake than that of thiolated chitosan-modified PLGA nanoparticles and unmodified PLA-PCL-TPGS nanoparticles. In vitro cell viability studies showed advantages of the thiolated chitosan-modified PLA-PCL-TPGS nanoparticles over Taxol® in terms of cytotoxicity against A549 cells. It seems that the mucoadhesive nanoparticles can increase paclitaxel transport by opening tight junctions and bypassing the efflux pump of P-glycoprotein. In conclusion, PLA-PCL-TPGS nanoparticles modified by thiolated chitosan could enhance the cellular uptake and cytotoxicity, which revealed a potential application for oral chemotherapy of lung cancer.     

Study on the visible-light-induced photokilling effect of nitrogen-doped TiO2 nanoparticles on cancer cells

Nitrogen-doped TiO2 (N-TiO2) nanoparticles were prepared by calcining the anatase TiO2 nanoparticles under ammonia atmosphere. The N-TiO2 showed higher absorbance in the visible region than the pure TiO2. The cytotoxicity and visible-light-induced phototoxicity of the pure- and N-TiO2 were examined for three types of cancer cell lines. No significant cytotoxicity was detected. However, the visible-light-induced photokilling effects on cells were observed. The survival fraction of the cells decreased with the increased incubation concentration of the nanoparticles. The cancer cells incubated with N-TiO2 were killed more effectively than that with the pure TiO2. The reactive oxygen species was found to play an important role on the photokilling effect for cells. Furthermore, the intracellular distributions of N-TiO2 nanoparticles were examined by laser scanning confocal microscopy. The co-localization of N-TiO2 nanoparticles with nuclei or Golgi complexes was observed. The aberrant nuclear morphologies such as micronuclei were detected after the N-TiO2-treated cells were irradiated by the visible light.     

A Novel Docetaxel-Loaded Poly (ε-Caprolactone)/Pluronic F68 Nanoparticle Overcoming Multidrug Resistance for Breast Cancer Treatment

Multidrug resistance (MDR) in tumor cells is a significant obstacle to the success of chemotherapy in many cancers. The purpose of this research is to test the possibility of docetaxel-loaded poly (ε-caprolactone)/Pluronic F68 (PCL/Pluronic F68) nanoparticles to overcome MDR in docetaxel-resistance human breast cancer cell line. Docetaxel-loaded nanoparticles were prepared by modified solvent displacement method using commercial PCL and self-synthesized PCL/Pluronic F68, respectively. PCL/Pluronic F68 nanoparticles were found to be of spherical shape with a rough and porous surface. The nanoparticles had an average size of around 200 nm with a narrow size distribution. The in vitro drug release profile of both nanoparticle formulations showed a biphasic release pattern. There was an increased level of uptake of PCL/Pluronic F68 nanoparticles in docetaxel-resistance human breast cancer cell line, MCF-7 TAX30, when compared with PCL nanoparticles. The cytotoxicity of PCL nanoparticles was higher than commercial Taxotere^® in the MCF-7 TAX30 cell culture, but the differences were not significant (p > 0.05). However, the PCL/Pluronic F68 nanoparticles achieved significantly higher level of cytotoxicity than both of PCL nanoparticles and Taxotere^® (p < 0.05), indicating docetaxel-loaded PCL/Pluronic F68 nanoparticles could overcome multidrug resistance in human breast cancer cells and therefore have considerable potential for treatment of breast cancer.     

Delivery of cisplatin by folic acid-targeted liposomal nanoparticles into liver cancer cell line

This study aimed to prepare cisplatin-loaded PEGylated liposomal nanoparticles targeted with folic acid and evaluate their efficacy on liver cancer cell line PLC/PRF/5 (Alexander hepatoma cell line). Nanoparticles were prepared by reverse phase evaporation technique and characterized by dynamic light scattering, scanning electron microscopy, transmission electron microscopy, inductively coupled plasma optical emission spectrometry, Fourier transform infrared spectroscopy, and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide techniques. Nanoscale particles with appropriate drug encapsulation efficiency (13%) were prepared. Cytotoxicity results indicated that the superior potency of targeted cisplatin-loaded nanoparticles compared to the nontargeted counterpart with 23% more cytotoxicity. Findings of this study confirmed the potency of targeted PEGylated liposomal nanoparticles.     

Smart Lipid–Polysaccharide Nanoparticles for Targeted Delivery of Doxorubicin to Breast Cancer Cells

In this study, actively-targeted (CD44-receptors) and dual stimuli (pH/redox)-responsive lipid–polymer nanoparticles were proposed as a delivery vehicle of doxorubicin hydrochloride in triple negative breast cancer cell lines. A phosphatidylcholine lipid film was hydrated with a solution of oxidized hyaluronic acid and doxorubicin, chosen as model drug, followed by a crosslinking reaction with cystamine hydrochloride. The obtained spherical nanoparticles (mean diameter of 30 nm) were found to be efficiently internalized in cancer cells by a receptor-mediated endocytosis process, and to modulate the drug release depending on the pH and redox potential of the surrounding medium. In vitro cytotoxicity assays demonstrated the safety and efficacy of the nanoparticles in enhancing the cytotoxic effect of the free anticancer drug, with the IC₅₀ values being reduced by two and three times in MDA-MB-468 and MDA-MB-231, respectively. The combination of self-assembled phospholipid molecules with a polysaccharide counterpart acting as receptor ligand, and stimuli-responsive chemical moieties, was carried out on smart multifunctional nanoparticles able to actively target breast cancer cells and improve the in vitro anticancer activity of doxorubicin.