Gold Nanorods Conjugated with Doxorubicin and cRGD for Combined Anticancer Drug Delivery and PET Imaging

Zirconium-containing nanoscale coordination polymers for positron emission tomography and fluorescence-guided cargo delivery to triple-negative breast tumors

Nanoscale coordination polymer (NCP) is a class of hybrid materials formed by self-assembly of metal ions and organic ligands through coordination. The applications of NCP in biomedicine are quite extensive due to the diversity choice of metal ions and organic ligands. Here we designed Zr-P1 NCP based on Zr4+ selected as metal ion nodes and tetrakis(4-carboxyphenyl) ethylene as bridging ligands. Zr-P1 NCP was modified with functionalized pyrene derived polyethylene glycol (Py-PAA-PEG-Mal) on the surface and further conjugated with cRGD for active targeting of integrin αvβ3 overexpressed in triple-negative breast cancer. Doxorubicin was loaded on Zr-P1 NCP with encapsulation efficiency up to 22 % for the treatment of triple negative breast cancer. 89Zr-P1 NCP can be used for in vivo tumor imaging due to the fluorescence properties resulting from the enhanced aggregation-induced Emission (AIE) behavior of P1 ligands and its positron emission tomography (PET) capability. Cellular evaluation indicated that the functionalized Zr-P1@PEG-RGD presented a good function for tumor cell targeting imaging and doxorubicin could be targeted to triple negative breast cancer when it was loaded onto Zr-P1@PEG-RGD, which corroborated with the in vivo results. In summary, 89Zr-P1@PEG-RGD can serve as a biocompatible nanoplatform for fluorescence and PET image-guided cargo delivery. STATEMENT OF SIGNIFICANCE: Nanoscale coordination polymer (NCP) is a class of hybrid materials formed by self-assembly of metal ions and organic ligands through coordination. The diversity of available metals and ligand structures upon NCP synthesis plays an advantage in establishing multimodal imaging platforms. Here we designed 89Zr-P1@PEG-RGD NCP based on Zr4+ selected as metal ion nodes and tetrakis(4-carboxyphenyl) ethylene as bridging ligands. 89Zr-P1@PEG-RGD nanomaterials have positron emission tomography (PET) capability due to the incorporation of zirconium-89, which can be used for in vivo tumor imaging with high sensitivity. The chemotherapeutic drug DOX was loaded on Zr-P1 NCP for the treatment of triple-negative breast cancer, and dual modality imaging can provide visual guidance for drug delivery.

Dual-targeting CD44 and mucin by hyaluronic acid and 5TR1 aptamer for epirubicin delivery into cancer cells: Synthesis, characterization, in vitro and in vivo evaluation

One of the revolutionized cancer treatment is active targeting nanomedicines. This study aims to create a dual-targeted drug delivery system for Epirubicin (EPI) to cancer cells. Hyaluronic acid (HA) is the first targeting ligand, and 5TR1 aptamer (5TR1) is the second targeting ligand to guide the dual-targeted drug delivery system to the cancer cells. HA is bound to highly expressed receptors like CD44 on cancer cells. 5TR1, DNA aptamer, is capable of recognizing MUC1 glycoprotein, which is overexpressed in cancer cells. The process involved binding EPI and 5TR1 to HA using adipic acid dihydrazide (AA) as a linker. The bond between the components was confirmed using 1H NMR. The binding of 5TR1 to HA-AA-EPI was confirmed using gel electrophoresis. The particle size (132.6 ± 9 nm) and Zeta Potential (-29 ± 4.4 mV) were measured for the final nanoformulation (HA-AA-EPI-5TR1). The release of EPI from the HA-AA-EPI-5TR1 nanoformulation was also studied at different pH levels. In the acidic pH (5.4 and 6.5) release pattern of EPI from the HA-AA-EPI-5TR1 nanoformulation was higher than physiological pH (7.4). The cytotoxicity and cellular uptake of the synthetic nanoformula were evaluated using MTT and flow cytometry analysis. Flow cytometry and cellular cytotoxicity studies were exhibited in a negative MUC1-cell line (CHO) and two positive MUC1+cell lines (MCF-7 and C26). Results confirmed that there is a notable contrast between the dual-targeted (HA-AA-EPI-5TR1) and single-targeted (HA-AA-EPI) nanoformulation in MCF-7 and C26 cell lines (MUC1+). In vivo studies showed that HA-AA-EPI-5TR1 nanoformulation has improved efficiency with limited side effect in C26 tumor-bearing mice. Also, Fluorescence imaging and pathological evaluation showed reduced side effects in the heart tissue of mice receiving HA-AA-EPI-5TR1 than free EPI. So, this targeted approach effectively delivers EPI to cancer cells with reduced side effects.

Biodistribution and Targeted Antitumor Effects of Trastuzumab-Modified Gold Nanorods in Mice with Gastric Cancer

BACKGROUND AND OBJECTIVES

Targeted drug is often engulfed and cleared by the reticuloendothelial system in vivo, resulting in reduced treatment efficacy. This study aimed to explore the biodistribution and HER-2-targeted antitumor effects of trastuzumab-modified gold nanorods (Tra-AuNRs) in a gastric cancer animal model.

METHODS

Gold nanorods were synthesized using a seed-mediated growth method, and then subjected to trastuzumab-targeted modification. Elemental analysis, Fourier transform infrared spectroscopy, and Xray photoelectron spectroscopy were performed; UV-visible absorption peak, photothermal effects, morphology, and size distribution of Tra-AuNRs were characterized. The targeted killing effect of Tra- AuNRs on gastric cancer cells was assessed in vitro. Tra-AuNRs were injected intravenously and intratumorally into gastric cancer-bearing nude mice in vivo and their distribution was detected. Tumor growth inhibition rate and tumor apoptosis-related protein expression were compared between groups.

RESULTS

Tra-AuNRs presented a relatively uniform morphology with an average particle size of 59.9 nm and a longitudinal plasmon resonance absorption peak of 790 nm. The targeted killing rate of gastric cancer cells in vitro by Tra-AuNRs was 87.9%. After intravenous injection, Tra-AuNRs were mainly distributed in the liver, tumor, spleen, and lungs. Comparatively, Tra-AuNRs were mainly distributed in the tumor when intratumorally injected, with a tumor concentration of 6.42 μg/g after 24 h. The tumor growth inhibition rate reached 78.3% in the intratumoral injection group, with significantly higher BAX, BAD, and CASPASE-3 expression than that in the intravenous injection group.

CONCLUSION

The findings suggest that Tra-AuNRs can be used for HER-2-positive gastric cancer treatment. Intratumoral injection of Tra-AuNRs significantly increased the local tumor drug concentration and improved the molecular targeted antitumor growth effect in gastric cancer-bearing nude mice.

Nanoparticle biodistribution coefficients: A quantitative approach for understanding the tissue distribution of nanoparticles

The objective of this manuscript is to provide quantitative insights into the tissue distribution of nanoparticles. Published pharmacokinetics of nanoparticles in plasma, tumor and 13 different tissues of mice were collected from literature. A total of 2018 datasets were analyzed and biodistribution of graphene oxide, lipid, polymeric, silica, iron oxide and gold nanoparticles in different tissues was quantitatively characterized using Nanoparticle Biodistribution Coefficients (NBC). It was observed that typically after intravenous administration most of the nanoparticles are accumulated in the liver (NBC = 17.56 %ID/g) and spleen (NBC = 12.1 %ID/g), while other tissues received less than 5 %ID/g. NBC values for kidney, lungs, heart, bones, brain, stomach, intestine, pancreas, skin, muscle and tumor were found to be 3.1 %ID/g, 2.8 %ID/g, 1.8 %ID/g, 0.9 %ID/g, 0.3 %ID/g, 1.2 %ID/g, 1.8 %ID/g, 1.2 %ID/g, 1.0 %ID/g, 0.6 %ID/g and 3.4 %ID/g, respectively. Significant variability in nanoparticle distribution was observed in certain organs such as liver, spleen and lungs. A large fraction of this variability could be explained by accounting for the differences in nanoparticle physicochemical properties such as size and material. A critical overview of published nanoparticle physiologically-based pharmacokinetic (PBPK) models is provided, and limitations in our current knowledge about in vitro and in vivo pharmacokinetics of nanoparticles that restrict the development of robust PBPK models is also discussed. It is hypothesized that robust quantitative assessment of whole-body pharmacokinetics of nanoparticles and development of mathematical models that can predict their disposition can improve the probability of successful clinical translation of these modalities.

Recent developments in silver nanoparticles utilized for cancer treatment and diagnosis: a patent review

Nanotheranostics is a young but rapidly expanding science that incorporates elements of therapy and diagnostics in a unique and miniscule area of research. The potential to combine diagnostic and therapeutic abilities inside a complete unit opens up interesting possibilities for innovative biomedical research. Silver-based nanoparticles, for instance, are widely utilized as pharmacological and biomedical imaging molecules, and hence offer a lot of potential for the development of versatile targeted therapy compositions. These nanoparticles have been used for cancer diagnosis and cancer treatments recently. We evaluate major innovations based on silver nanotheranostics technologies in this review paper, with an emphasis on cancer treatment implications. The present review covers papers, from 2010 to 2020.

Surface Engineered Dendrimers: A Potential Nanocarrier for the Effective Management of Glioblastoma Multiforme

Gliomas are the most prevailing intracranial tumors, which account for approximately 36% of the primary brain tumors of glial cells. Glioblastoma multiforme (GBM) possesses a higher degree of malignancy among different gliomas. The blood-brain barrier (BBB) protects the brain against infections and toxic substances by preventing foreign molecules or unwanted cells from entering the brain parenchyma. Nano-carriers such as liposomes, nanoparticles, dendrimers, etc. boost the brain permeability of various anticancer drugs or other drugs. The favorable properties like small size, better solubility, and the modifiable surface of dendrimers have proven their broad applicability in the better management of GBM. However, in vitro and in vivo toxicities caused by dendrimers have been a significant concern. The presence of multiple functionalities on the surface of dendrimers enables the grafting of target ligand and/or therapeutic moieties. Surface engineering improves certain properties like targeting efficiency, pharmacokinetic profile, therapeutic effect, and toxicity reduction. This review will be focused on the role of different surface-modified dendrimers in the effective management of GBM.

The Emerging Role of Ultrasonic Nanotechnology for Diagnosing and Treatment of Diseases

Nanotechnology has been commonly used in a variety of applications in recent years. Nanomedicine has also gotten a lot of attention in the medical and treatment fields. Ultrasonic technology is already being used in research as a powerful tool for manufacturing nonmaterial and in the decoration of catalyst supports for energy applications and material processing. For the development of nanoparticles and the decoration of catalytic assisted powders with nanoparticles, low or high-frequency Ultrasonic are used. The Ultrasonic is frequently used in joint venture with the nanotechnology from the past few years and bring tremendous success in various diseases diagnosing and treatment. Numerous kinds of nanoparticles are fabricated with desired capabilities and targeted toward different targets. This review first highlights the Ultrasonic Treatment and processing of Nanoparticles for Pharmaceuticals. Next, we explain various nanoparticles with ultrasonic technology for different diagnosing and treatment of various diseases. Finally, we explain the challenges face by current approaches for their translation in clinics.

Advanced Optical Imaging-Guided Nanotheranostics towards Personalized Cancer Drug Delivery

Nanomedicine involves the use of nanotechnology for clinical applications and holds promise to improve treatments. Recent developments offer new hope for cancer detection, prevention and treatment; however, being a heterogenous disorder, cancer calls for a more targeted treatment approach. Personalized Medicine (PM) aims to revolutionize cancer therapy by matching the most effective treatment to individual patients. Nanotheranostics comprise a combination of therapy and diagnostic imaging incorporated in a nanosystem and are developed to fulfill the promise of PM by helping in the selection of treatments, the objective monitoring of response and the planning of follow-up therapy. Although well-established imaging techniques, such as Magnetic Resonance Imaging (MRI), Computed Tomography (CT), Positron Emission Tomography (PET) and Single-Photon Emission Computed Tomography (SPECT), are primarily used in the development of theranostics, Optical Imaging (OI) offers some advantages, such as high sensitivity, spatial and temporal resolution and less invasiveness. Additionally, it allows for multiplexing, using multi-color imaging and DNA barcoding, which further aids in the development of personalized treatments. Recent advances have also given rise to techniques permitting better penetration, opening new doors for OI-guided nanotheranostics. In this review, we describe in detail these recent advances that may be used to design and develop efficient and specific nanotheranostics for personalized cancer drug delivery.

A novel formulation of theranostic nanomedicine for targeting drug delivery to gastrointestinal tract cancer

Background

Theranostic nanomedicines contain a nanovehicle that has fluorescent properties and can be used for diagnostic, therapeutic and prognostic purposes. The transferrin receptor expression is 1000-fold higher in rapidly growing cancer cells as compared to the normal cells and, therefore, can be used in targeted drug delivery systems. The objective of the present study was to design a novel targeted gold nanoparticle (GNPs)-based theranostic formulation for gastrointestinal (GI) tract-related cancers. The synthesized GNPs were conjugated to transferrin and doxorubicin both separately and collectively to check their cytotoxic properties. The in vitro cytotoxicity of nanocomposites was observed against colon cancer cell line HCT-116. The doxorubicin conjugated nanocomposites showed almost the same cytotoxicity, but more effect at later hours (h). The IC50 and IC100 were 50 µg/ml and 250 µg/ml, respectively, equivalent to the doxorubicin weight for GNP theranostic nanomedicine.

Results

The maximum effect was observed after 12 h and nanomedicines were still active after 72 h of treatment. Our in vivo data proved that nanomedicine crossed all the barriers and was successfully delivered to the tumour cells. Theranostic nanomedicine’s (TNM) effect on body weight and survival rate on mice was many folds better than mice in pure doxorubicin group. It also showed almost 80% survival rate on day 40. The in vivo and in vitro results show the effects of prolonged drug release and the nanomedicine was not toxic to vital organs of the animal.

Conclusion

This is one of its kind studies in which a novel targeted nanomedicines approach was formulated for therapeutic as well as prognostic purposes against GI tract cancer.

Graphic Abstract

Computational study of therapeutic potential of phosphorene as a nano-carrier for drug delivery of nebivolol for the prohibition of cardiovascular diseases: a DFT study

Density functional theory (DFT) calculations were utilized to assess the drug delivery efficiency of phosphorene carrier for nebivolol drug to treat cardiovascular diseases. The optimized structures, excited state, and electronic properties of nebivolol, phosphorene, and nebivolol-phosphorene (nebivolol-PH) complex were considered to determine the drug delivery ability of phosphorene at the target site. The increased dipole moment (6.08 D) results in the higher solubility of the complex in polar solvents (water). Weak interactive forces between nebivolol and phosphorene were demonstrated by the non-covalent interaction (NCI) plot that facilitated the offloading of nebivolol at the targeted area. The analysis of frontier molecular orbitals (FMOs) revealed that during excitation, the charge was transferred from nebivolol as a higher occupied molecular orbital (HOMO) to phosphorene as a lower unoccupied molecular orbital (LUMO). Thus, the charge-transfer process was further studied by charge decomposition analysis (CDA). The calculated results at the excited state for the nebivolol-PH complex exhibited that the maximum wavelength (λmax) was red-shifted by 6 nm in the gas phase. The electron-hole theory and photoinduced electron transfer (PET) processes were carried out for the exploration of different excited states of the complex. Additionally, phosphorene with + 1 and - 1 charge states indicated the minor structural changes and provide the stable nebivolol-PH complex. This theoretical study also investigated that phosphorene can be exploited as an effective carrier for the delivery of a therapeutic agent as nebivolol to treat cardiovascular diseases. This work will also encourage the researchers to investigate the other 2D nanoparticles as a nano-drug delivery system (NDDS).

The Synthesis and Evaluation of RGD-Conjugated Chitosan Gel as Daily Supplement for Body Weight Control

(1) Background: Obesity is one of the most widespread chronic diseases and increases the risk of several other chronic diseases, especially type 2 diabetes. (2) Methods: Endobarrier is a new medical device what is worn in the small intestines for the treatment of type 2 diabetes and obesity. However, given the invasive and other adverse effects of the Endobarrier, we propose the use of RGD peptide conjugated with chitosan (RC) as an alternative. (3) Results: The FTIR and NMR spectrum showed RGD peptide was successfully conjugated on chitosan and RGD−CT is retained in the small intestine even after digestion. In vitro of wst-1 and live and dead staining studies show that the RGD−CT gel is highly biocompatible and non-toxic. Rats treated with the RGD−CT gel for a short term showed significant decrease change more than 30% in body weight, while the blood and hematic biometrics were within normal values. (4) Conclusions: The RGD−CT gel is safe, suitable for the short-term, reducing visceral fat rate health food to control weight. In the future, it is expected to develop a safe, long-term effective, flexibility of use and low-side-effect anti-obesity therapy in the era of precision medicine by further modification.

Multifunctional Gold Nanorod for Therapeutic Applications and Pharmaceutical Delivery Considering Cellular Metabolic Responses, Oxidative Stress and Cellular Longevity

Multifunctional gold nanorods (GNR) have drawn growing interest in biomedical fields because of their excellent biocompatibility, ease of alteration, and special optical properties. The great advantage of using GNR in medicine is their application to Photothermal therapy (PPTT), which is possible thanks to their ability to turn luminous energy into heat to cause cellular hyperthermia. For this purpose, the relevant articles between 1988 and 2020 were searched in databases such as John Wiley, Free paper, Scopus, Science Direct, and Springer to obtain the latest findings on multifunctional gold nanorods for therapeutic applications and pharmaceutical delivery. In this article, we review recent progress in diagnostic and therapeutic applications of multifunctional GNR, highlighting new information about their toxicity to various cellular categories, oxidative stress, cellular longevity, and their metabolic effects, such as the effect on the energy cycles and genetic structures. The methods for the synthesis and functionalization of GNR were surveyed. This review includes new information about GNR toxicity to various cellular categories and their metabolic effects.

Gold nanoparticles meet medical radionuclides

Thanks to their unique optical and physicochemical properties, gold nanoparticles have gained increased interest as radiosensitizing, photothermal therapy and optical imaging agents to enhance the effectiveness of cancer detection and therapy. Furthermore, their ability to carry multiple medically relevant radionuclides broadens their use to nuclear medicine SPECT and PET imaging as well as targeted radionuclide therapy. In this review, we discuss the radiolabeling process of gold nanoparticles and their use in (multimodal) nuclear medicine imaging to better understand their specific distribution, uptake and retention in different in vivo cancer models. In addition, radiolabeled gold nanoparticles enable image-guided therapy is reviewed as well as the enhancement of targeted radionuclide therapy and nanobrachytherapy through an increased dose deposition and radiosensitization, as demonstrated by multiple Monte Carlo studies and experimental in vitro and in vivo studies.

Dual-Stimuli-Responsive Nanotheranostics for Dual-Targeting Photothermal-Enhanced Chemotherapy of Tumor

Stimuli-responsive nanotheranostics have been widely explored for precision medicine. Here, we developed a pH/light dual-stimuli-responsive nanotheranostic agent for biological/physical dual-targeting photothermal-enhanced chemotherapy of U87MG tumor. This nanotheranostic agent was composed of the RGD (Arg-Gly-Asp) peptide, melanin-coated magnetic nanoparticles (MMNs), doxorubicin (DOX), and indocyanine green (ICG), denoted as RMDI. The tumor accumulation of RMDI was simultaneously improved through biological active targeting by RGD and physical magnetic targeting by an external magnetic field at tumor tissues, which was proven by in vivo photoacoustic/magnetic resonance/fluorescence (PA/MR/FL) trimodal imaging. Under dual stimuli of the tumor acidic microenvironment and laser irradiation, both DOX and ICG were released in a controlled fashion, demonstrating impressive therapeutic outcomes against U87MG tumor both in vitro and in vivo, respectively. Owing to the synergistic photothermal/chemotherapy, the dual-stimuli-responsive and dual-targeting nanotheranostic agent completely ablated U87MG tumor in vivo without any tumor recurrence and biotoxicity. This nanotheranostic agent exhibited great potential in multimodal imaging-guided synergistic therapy of cancer.

Doxorubicin (DOX) Gadolinium-Gold-Complex: A New Way to Tune Hybrid Nanorods as Theranostic Agent

INTRODUCTION

In this paper, we have designed and formulated, a novel synthesis of doxorubicin (DOX) loaded bimetallic gold nanorods in which gold salt (HAuCl4) is chelated with anthracycline (DOX), diacid polyethylene-glycol (PEG-COOH) and gadolinium salt (GdCl3 * 6 H2O) to form DOX IN-Gd-AuNRs compared with DOX ON-Gd-AuNRs in which the drug was grafted onto the bimetallic pegylated nanoparticle surface by electrostatic adsorption.

MATERIAL AND METHOD

The physical and chemical evaluation was performed by spectroscopic analytical techniques (Raman spectroscopy, UV-Visible and transmission electron microscopy (TEM)). Magnetic features at 7T were also measured. Photothermal abilities were assessed. Cytotoxicity studies on MIA PaCa-2, human pancreatic carcinoma and TIB-75 hepatocytes cell lines were carried out to evaluate their biocompatibility and showed a 320 fold higher efficiency for DOX after encapsulation.

RESULTS

Exhaustive physicochemical characterization studies were conducted showing a mid size of 20 to 40 nm diameters obtained with low polydispersity, efficient synthesis using seed mediated synthesis with chelation reaction with high scale-up, long duration stability, specific doxorubicin release with acidic pH, strong photothermal abilities at 808 nm in the NIR transparency window, strong magnetic r1 relaxivities for positive MRI, well adapted for image guided therapy and therapeutical purpose in biological tissues.

CONCLUSION

In this paper, we have developed a novel theranostic nanoparticle composed of gadolinium complexes to gold ions, with a PEG biopolymer matrix conjugated with antitumoral doxorubicin, providing multifunctional therapeutic features. Particularly, these nano conjugates enhanced the cytotoxicity toward tumoral MIAPaCa-2 cells by a factor of 320 compared to doxorubicin alone. Moreover, MRI T1 features at 7T enables interesting positive contrast for bioimaging and their adapted size for potential passive targeting to tumors by Enhanced Permeability Retention. Given these encouraging antitumoral and imaging properties, this bimetallic theranostic nanomaterial system represents a veritable promise as a therapeutic entity in the field of medicinal applications.

Advances in Development of Radiometal Labeled Amino Acid-Based Compounds for Cancer Imaging and Diagnostics

Radiolabeled biomolecules targeted at tumor-specific enzymes, receptors, and transporters in cancer cells represent an intensively investigated and promising class of molecular tools for the cancer diagnosis and therapy. High specificity of such biomolecules is a prerequisite for the treatment with a lower burden to normal cells and for the effective and targeted imaging and diagnosis. Undoubtedly, early detection is a key factor in efficient dealing with many severe tumor types. This review provides an overview and critical evaluation of novel approaches in the designing of target-specific probes labeled with metal radionuclides for the diagnosis of most common death-causing cancers, published mainly within the last three years. Advances are discussed such traditional peptide radiolabeling approaches, and click and nanoparticle chemistry. The progress of radiolabeled peptide based ligands as potential radiopharmaceuticals is illustrated via novel structure and application studies, showing how the molecular modifications reflect their binding selectivity to significant onco-receptors, toxicity, and, by that, practical utilization. The most impressive outputs in categories of newly developed structures, as well as imaging and diagnosis approaches, and the most intensively studied oncological diseases in this context, are emphasized in order to show future perspectives of radiometal labeled amino acid-based compounds in nuclear medicine.

Copper-64 labeled nanoparticles for positron emission tomography imaging: a review of the recent literature

INTRODUCTION

Nuclear medicine plays a crucial role for personalized therapy, mainly in oncology. Chemotherapy and radiotherapy present some disadvantages and research is shifting toward nanotechnology with significant improvements in therapy and diagnosis of several cancers. Indeed, nanoparticles can be tagged with different radioisotopes for single photon emission computed tomography (SPECT) and positron emission tomography (PET) imaging and for therapy. This review describes the current state of the art of ⁶⁴Copper-labeled nanoparticles for PET imaging of cancer.

EVIDENCE ACQUISITION

We performed a systematic analysis of literature using the terms "64CuCl<inf>2</inf>," "64Cu," "Copper" AND "nanoparticle" AND "PET" in online databases: i.e. PubMed/MEDLINE and Scopus. The search was limited to English papers and original articles. We excluded articles not in English language, abstracts, case reports, review articles and meeting presentations.

EVIDENCE SYNTHESIS

Amongst the 116 articles retrieved, 88 were excluded because reviews, or not in English, or only in-vitro studies or meeting presentations. We considered only 28 original papers. The most used nanoparticles are liposomes and they are mainly used in breast cancer although other animal models of cancer have been also investigated.

CONCLUSIONS

The results showed that nanoparticles can be considered a promising radiopharmaceutical for PET imaging of different type of cancer.

A general-purpose Nanohybrid fabricated by Polymeric Au(I)-peptide precursor to wake the function of Peptide Therapeutics

Peptide-derived nanocomposites have been exhibiting fascinating biological advantages, including but not limited to excellent biocompatibility, biological degradation, high targetability and subsequent potent therapeutic efficacy. While some successes have been achieved in the nanoengineering of peptide-based architectures with defined dimensions and medical functions, enormous challenges remain about clinical nano-pharmaceutics of peptides, especially those modulating intracellular protein-protein interactions (PPIs). Methods: We developed a general method to translate intracellular-PPI-targeted peptides into a bioavailable peptide-auric spheroidal nanohybrid (SNH), for which polymeric peptide-Auric precursors [Au1+-S-peptide]n are in-situ reduced on the surface of gold nanoseeds via a simple and mild reaction. As proofs of concept, three cytomembrane-impenetrable peptides with different physicochemical properties were successfully engineered into stable and tumor-specific SNH respectively. Results: To highlight the advantage of SNH, PMI, a hydrophobic and enzyme-intolerant peptide capable of p53 restoration, was selected to challenge the power of SNH in a colon tumor xenografts model. PMI-Au SNH in vivo suppressed tumor growth potently after three administrations: intravenous injection, intraperitoneal injection and gastric perfusion, and maintained a favorable therapeutic safety. Conclusion: This therapeutically feasible strategy of peptide nanoengineering will allow us to fabricate a series of nanomedicines to modulate carcinogenic PPIs that hide and multiply inside cells, and in all likelihood reinvigorate the development of peptide drug against wide varieties of human diseases.

Novel Chemo-Photothermal Therapy in Breast Cancer Using Methotrexate-Loaded Folic Acid Conjugated Au@SiO2 Nanoparticles

Low level laser therapy (LLLT) is known as a safe type of phototherapy to target tumor tissue/cells. Besides, using targeted nanoparticles increases the successfulness of cancer therapy. This study was designed for investigating the combined effect of folate (FA)/Methotrexate (MTX) loaded silica coated gold (Au@SiO2) nanoparticles (NPs) and LLLT on the fight against breast cancer.NPs were synthesized and characterized using FTIR, TEM and DLS-Zeta. The NPs had spherical morphology with mean diameter of around 25 nm and positive charge (+13.3 mV) while after conjugation with FA and MTX their net charge reduced to around -19.7 mV.Our findings in cell uptake studies clearly showed enhanced cellular uptake of NPs after FA and MTX loaded NPs in both breast cancer cell lines especially on MDA-MB-231 due to high expression of folate receptors. The results indicated that LLLT had a proliferative effect on both breast cancer cell lines but in the presence of engineered breast cancer targeted nanoparticle, the efficacy of combination chemo-photothermal therapy was significantly increased using MTT assay (p<0.05), DAPI staining, and cell cycle findings. The highest apoptotic effect on breast cancer cell lines was observed in the cells exposed to a combination of MTX-FA loaded Au@SiO2 NP and LLLT proved by DAPI staining and cell cycle(by increasing the cell arrest in subG0/G1). Taken together a combination of chemotherapy and LLLT improves the potential of breast cancer therapy with minimum side effects.

A glance over doxorubicin based-nanotherapeutics: From proof-of-concept studies to solutions in the market

Cancer is one of the leading causes of death worldwide and, as such, efforts are being done to find new chemotherapeutic drugs or, alternatively, novel approaches for the delivery of old ones. In this scope, when used as vehicles for drugs, nanomaterials may potentially maximize the efficacy of the treatment and reduce its side effects, for example by a change in drug's pharmacokinetics, cell targeting and/or specific stimuli-responsiveness. This is the case of doxorubicin (DOX) that presents a broad spectrum of activity and is one of the most widely used chemotherapeutic drugs as first-line treatment. Indeed, DOX is a very interesting example of a drug for which several nanosized delivery systems have been developed over the years. While it is true that some of these systems are already in the market, it is also true that research on this subject remains very active and that there is a continuing search for new solutions. In this sense, this review takes the example of doxorubicin, not so much with the focus on the drug itself, but rather as a case study around which very diverse and imaginative nanotechnology approaches have emerged.

Improving nanotherapy delivery and action through image-guided systems pharmacology

Despite recent advances in the translation of therapeutic nanoparticles (TNPs) into the clinic, the field continues to face challenges in predictably and selectively delivering nanomaterials for the treatment of solid cancers. The concept of enhanced permeability and retention (EPR) has been coined as a convenient but simplistic descriptor of high TNP accumulation in some tumors. However, in practice EPR represents a number of physiological variables rather than a single one (including dysfunctional vasculature, compromised lymphatics and recruited host cells, among other aspects of the tumor microenvironment) — each of which can be highly heterogenous within a given tumor, patient and across patients. Therefore, a clear need exists to dissect the specific biophysical factors underlying the EPR effect, to formulate better TNP designs, and to identify patients with high-EPR tumors who are likely to respond to TNP. The overall pharmacology of TNP is governed by an interconnected set of spatially defined and dynamic processes that benefit from a systems-level quantitative approach, and insights into the physiology have profited from the marriage between in vivo imaging and quantitative systems pharmacology (QSP) methodologies. In this article, we review recent developments pertinent to image-guided systems pharmacology of nanomedicines in oncology. We first discuss recent developments of quantitative imaging technologies that enable analysis of nanomaterial pharmacology at multiple spatiotemporal scales, and then examine reports that have adopted these imaging technologies to guide QSP approaches. In particular, we focus on studies that have integrated multi-scale imaging with computational modeling to derive insights about the EPR effect, as well as studies that have used modeling to guide the manipulation of the EPR effect and other aspects of the tumor microenvironment for improving TNP action. We anticipate that the synergistic combination of imaging with systems-level computational methods for effective clinical translation of TNPs will only grow in relevance as technologies increase in resolution, multiplexing capability, and in the ability to examine heterogeneous behaviors at the single-cell level.

Poly-amino acids coated gold nanorod and doxorubicin for synergistic photodynamic therapy and chemotherapy in ovarian cancer cells

In this work, we have successfully designed and formulated a doxorubicin-loaded polypeptide-based multilayer assembled gold nanorod (DH-GNR). We have hypothesized that near-infrared (NIR) laser irradiation of DH-GNR will combine the benefits of chemotherapy and photothermal therapy. The GNR was surface functionalized with poly-glutamic acid (PGA) and poly-l-Lysine (PLL) with a final layer of hyaluronic acid (HA) that could also serve as a targeting ligand toward the overexpressed CD44 receptors in ovarian cancer cells. The zigzag ζ potential of nanoparticle is a proof of successful assembly of alternative polymers on the GNR surface. NIR irradiation exhibited a burst release of drug in pH 7.4 and pH 5.0 buffer conditions. The combination of doxorubicin (DOX)-based chemotherapy and GNR-based photothermal therapy exhibited a synergistic effect in killing the SKOV3 cancer cells. DH-GNR(+NIR) induced a 82.5% apoptosis (combined early and late apoptosis) compared with only 35.2 and 38.5% for DOX or DH-GNR(-NIR) treated cell group. Results clearly suggest that the excessive reactive oxygen species (ROS) generation in DH-GNR (+NIR) might be responsible for the cell apoptosis and cell death. The promising anticancer effect of DH-GNR will be of great potential in the treatment of ovarian cancers and worth further development for treating other malignant tumors.

Bubble-Manipulated Local Drug Release from a Smart Thermosensitive Cerasome for Dual-Mode Imaging Guided Tumor Chemo-Photothermal Therapy

Thermosensitive liposomes have demonstrated great potential for tumor-specific chemotherapy. Near infrared (NIR) dyes loaded liposomes have also shown improved photothermal effect in cancer theranostics. However, the instability of liposomes often causes premature release of drugs or dyes, impeding their antitumor efficacy. Herein, we fabricated a highly stable thermo-responsive bubble-generating liposomal nanohybrid cerasome with a silicate framework, combined with a NIR dye to achieve NIR light stimulated, tumor-specific, chemo-photothermal synergistic therapy. Methods: In this system, NIR dye of 1,1'-Dioctadecyl-3,3,3',3'- Tetramethylindotricarbocyanine iodide (DiR) with long carbon chains was self-assembled with a cerasome-forming lipid (CFL) to encapsulate ammonium bicarbonate (ABC), which was further used for actively loading doxorubicin (DOX), affording a thermosensitive and photosensitive DOX-DiR@cerasome (ABC). Results: The resulting cerasome could disperse well in different media. Upon NIR light mediated thermal effect, ABC was decomposed to generate CO2 bubbles, resulting in a permeable channel in the cerasome bilayer that significantly enhanced DOX release. After intravenous injection into tumor-bearing mice, DOX-DiR@cerasome (ABC) could be efficiently accumulated at the tumor tissue, as monitored by DiR fluorescence, lasting for more than 5 days. NIR light irradiation was then performed at 36h to locally heat the tumors, resulting in immediate CO2 bubble generation, which could be clearly detected by ultrasound imaging, facilitating the monitoring process of controlled release of the drug. Significant antitumor efficacy could be obtained for the DOX-DiR@cerasome (ABC) + laser group, which was further confirmed by tumor tissue histological analysis.

Next-generation nanotheranostics targeting cancer stem cells

Cancer is depicted as the most aggressive malignancy and is one the major causes of death worldwide. It originates from immortal tumor-initiating cells called 'cancer stem cells' (CSCs). This devastating subpopulation exhibit potent self-renewal, proliferation and differentiation characteristics. Dynamic DNA repair mechanisms can sustain the immortality phenotype of cancer to evade all treatment strategies. To date, current conventional chemo- and radio-therapeutic strategies adopted against cancer fail in tackling CSCs. However, new advances in nanotechnology have paved the way for creating next-generation nanotheranostics as multifunctional smart 'all-in-one' nanoparticles. These particles integrate diagnostic, therapeutic and targeting agents into one single biocompatible and biodegradable carrier, opening up new avenues for breakthroughs in early detection, diagnosis and treatment of cancer through efficient targeting of CSCs.

Triggered RNAi Therapy Using Metal Inorganic Nanovectors

The administration of small interfering RNA (siRNA) is a very interesting therapeutic option to treat genetic diseases such as Alzheimer's or some types of cancer, but its effective delivery still remains a challenge. Herein, Au nanorod (GNR)-based platforms functionalized with polyelectrolyte layers were developed and analyzed as potential siRNA nanocarriers. The polymeric layers were successfully assembled on the particle surfaces by means of the layer-by-layer assembly technique through the alternating deposition of oppositely charged poly(styrene)sulfonate, PSS, poly(lysine), PLL, and siRNA biopolymers, with a final hyaluronic acid layer in order to provide the nanoconstructs with a potential targeting ability as well as colloidal stability in physiological medium. Once the hybrid nanocarriers were obtained, the cargo release, their colloidal stability in physiological-relevant media, cytotoxicity, cellular internalization and uptake, and knockdown activity were studied. The present hybrid particles release the genetic material inside cells by means of a protease-assisted and/or a light-triggered release mechanism in order to control the delivery of the oligonucleotides on demand. In addition, the hybrid nanovectors were observed to be nontoxic to cells and could efficiently deliver the genetic material in the cell cytoplasms. The GNR-based nanocarriers proposed here can provide a suitable environment to load and protect a sufficient amount of the genetic material to allow an efficient and sustained knockdown gene expression for long (up to 93% for 72 h), thanks to the slow degradation of PLL, without the observation of adverse side toxic effects. It was also found that the silencing activity was enhanced with the number of siRNA layers assembled in the nanoplatforms.

Dual Responsive Polymersomes for Gold Nanorod and Doxorubicin Encapsulation: Nanomaterials with Potential Use as Smart Drug Delivery Systems

In the present study, poly(ethylene glycol)-b-poly(N,N-diethylaminoethyl methacrylate) (PEG-b-PDEAEM) amphiphilic block copolymers were synthetized by reversible addition-fragmentation chain transfer (RAFT) polymerization using two different macro chain transfer agents containing PEG of 2000 and 5000 g/mol and varying the length of the PDEAEM segment. From the obtained block copolymers, polymersome type nanometric aggregates were obtained by two different techniques. By direct dispersion, particle diameters around 200 nm were obtained, while by solvent exchange using THF and water, the obtained diameters were around 100 nm. These block copolymers were used to encapsulate gold nanorods and doxorubicin (DOX) with good efficiencies to obtain nanomaterials with potential use as dual stimuli-sensitive drug delivery systems for combined anticancer therapies. Drug delivery studies showed that the release rate of DOX was accelerated when the pH was lowered from 7.4 to 5.8 and also when the systems were irradiated with a NIR laser at pH 7.4. The combination of lower pH and near infrared (NIR) irradiation resulted in higher drug release only in the case of polymersomes with lower molecular weight PEG.

Clinical scale synthesis of intrinsically radiolabeled and cyclic RGD peptide functionalized 198Au nanoparticles for targeted cancer therapy

INTRODUCTION

The emerging concept of intrinsically radiolabeled nanoparticles has the potential to transform the preclinical and clinical studies by improving the in vivo stability and demonstrating minimal alteration in the inherent pharmacokinetics of the nanoparticles. In this paper, a simple and efficient single-step method for clinical scale synthesis of intrinsically radiolabeled ¹⁹⁸Au nanoparticles conjugated with cyclic arginine-glycine-aspartate peptide (¹⁹⁸AuNP-RGD) is reported for potential use in targeted cancer therapy.

METHODS

Large radioactive doses (>37 GBq) of ¹⁹⁸AuNP-RGD were synthesized by reaction of ¹⁹⁸Au-HAuCl₄ with cyclic RGD peptide. The synthesized nanoparticles were characterized by various analytical techniques. In vitro cell binding studies were carried out in B16F10 (murine melanoma) cell line. Biodistribution studies were carried out in melanoma tumor bearing C57BL/6 mice to demonstrate the tumor targeting ability of ¹⁹⁸AuNP-RGD. The therapeutic efficacy of ¹⁹⁸AuNP-RGD was evaluated by carrying out systematic tumor regression studies in melanoma tumor bearing mice after intravenous administration of the radioactive doses.

RESULTS

Well dispersed and biocompatible nanoparticles (~12.5 nm diameter) could be synthesized with excellent radiochemical and colloidal stability. In vitro studies exhibited the cell binding affinity and specificity of ¹⁹⁸AuNP-RGD towards melanoma cell line. A high uptake of 8.7 ± 2.1%ID/g in the tumor was observed within 4 h post-injection (p.i.). Significant decrease in tumor uptake of ¹⁹⁸AuNP-RGD (2.9 ± 0.8%ID/g) at 4 h p.i. on co-injection of a blocking dose of the peptide suggested that tumor localization of the intrinsically radiolabeled nanoparticles was receptor mediated. Administration of 37.0 MBq of ¹⁹⁸AuNP-RGD resulted in significant regression of tumor growth with no apparent body weight loss over a period of 15 d.

CONCLUSIONS

Overall, these promising results demonstrate the suitability of ¹⁹⁸AuNP-RGD as an advanced functional nanoplatform for targeted cancer therapy.

Gold nanorods: from anisotropy to opportunity. An evolution update

Gold nanoparticles have drawn attention to nanomedicine for many years due to their physicochemical properties, which include: good stability; biocompatibility; easy surface chemistry and superior magnetic; and last, electronic properties. All of these properties distinguish gold nanoparticles as advantageous carriers to be exploited. The challenge to develop new gold nanostructures has led to anisotropy, a new property to exploit for various medical applications: diagnostic and imaging strategies as well as therapeutic options. Gold nanorods are the most studied anisotropic gold nanoparticles because of the presence of two absorption peaks according to their longitudinal and transversal plasmon resonances. The longitudinal surface plasmonic resonance can provide the absorption in the near-infrared region and this is an important aspect of using gold nanorods for medical purposes.

Bimetallic gold nanorods with enhanced biocorona formation for doxorubicin loading and sustained release

The biomedical applicability of gold nanorods (AuNRs) arises due to their interesting optical and photothermal properties, which can result in the formation of a protein corona layer when exposed to the physiological system. The current study focuses on the effect of bimetallic coatings of AuNRs (AuNRs@Pd and AuNRs@Cu) on protein corona formation, and the potential application of protein-coronated bimetallic AuNRs was investigated for doxorubicin (dox) loading, release, and in vitro cytotoxicity analysis. Two significant proteins in blood serum, namely, human serum albumin (HSA) and transferrin, were chosen for the protein coronation. The variations in the protein adsorption patterns of monometallic and bimetallic AuNRs were studied based on the protein adsorption, zeta potential, and particle size measurements. A higher adsorption of hard and soft corona was observed for HSA due to their higher abundance and reactivity. The enhanced electropositive nature of these bimetals promoted higher corona formation (AuNR@Pd > AuNR@Cu > AuNRs) when compared with bare AuNRs, which in turn correlated with higher dox loading. The higher corona on bimetallic AuNRs helped to overcome the burst release of dox over a period of 48 h (AuNRs@Pd > AuNR@Cu > AuNRs) when compared to the respective monometallic AuNRs, and the dox release was slightly increased when tested in human plasma. Furthermore, a significant decrease in the cytotoxicity of protein-coronated bimetallic AuNRs as compared to monometallic AuNRs was also observed. Thus, it can be suggested that the use of engineered protein corona on bimetallic nanostructures can open new areas of research for cancer therapeutics.

Gold nanostructures as cancer theranostic probe: promises and hurdles

Gold nanostructures (GNSts) have emerged as substitute for conventional contrast agents in imaging techniques and therapeutic probes due to their tunable surface plasmon resonance and optical properties in near-infrared region. Thus GNSts provide platform for the amalgamation of diagnosis and treatment (theranostics) into a single molecule for a more precise treatment. Hence, the article talks about the application of GNSts in imaging techniques and provide a holistic view on differently shaped GNSts in cancer theranostics. However, with promises GNSts also face various hurdles for their use as theranostic probe which are primarily associated with toxicity. Finally, the article attempts to discuss the challenges faced by GNSts and the way ahead that need to be traversed to place them in nanomedicine.

Molecular-Level "Observations" of the Behavior of Gold Nanoparticles in Aqueous Solution and Interacting with a Lipid Bilayer Membrane

We use coarse-grained molecular dynamics simulations to "observe" details of interactions between ligand-covered gold nanoparticles and a lipid bilayer model membrane. In molecular dynamics simulations, one puts the individual atoms and groups of atoms of the physical system to be "observed" into a simulation box, specifies the forms of the potential energies of interactions between them (ultimately quantum based), and lets them individually move classically according to Newton's equations of motion, based on the forces arising from the assumed potential energy forms. The atoms that are chemically bonded to each other stay chemically bonded, following known potentials (force fields) that permit internal degrees of freedom (internal rotation, torsion, vibrations), and the interactions between nonbonded atoms are simplified to Lennard-Jones forms (in our case) and coulombic (where electrical charges are present) in which the parameters are previously optimized to reproduce thermodynamic properties or are based on quantum electronic calculations. The system is started out at a reasonable set of coordinates for all atoms or groups of atoms, and then permitted to develop according to the equations of motion, one small step (usually 10 fs time step) at a time, for millions of steps until the system is at a quasi-equilibrium (usually reached after hundreds of nanoseconds). We then let the system play out its motions further for many nanoseconds to observe the behavior, periodically taking snapshots (saving all positions and energies), and post-processing the snapshots to obtain various average descriptions of the system. Alkanethiols of various lengths serve as examples of hydrophobic ligands and methyl-terminated PEG with various numbers of monomer units serve as examples of hydrophilic ligands. Spherical gold particles of various diameters as well as gold nanorods form the core to which ligands are attached. The nanoparticles are characterized at the molecular level, especially the distributions of ligand configurations and their dependence on ligand length, and surface coverage. Self-assembly of the bilayer from an isotropic solution and observation of membrane properties that correspond well to experimental values validate the simulations. The mechanism of permeation of a gold NP coated with either a hydrophobic or a hydrophilic ligand, and its dependence on surface coverage, ligand length, core diameter, and core shape, is investigated. Lipid response such as lipid flip-flops, lipid extraction, and changes in order parameter of the lipid tails are examined in detail. The mechanism of permeation of a PEGylated nanorod is shown to occur by tilting, lying down, rotating, and straightening up. The nature of the information provided by molecular dynamics simulations permits understanding of the detailed behavior of gold nanoparticles interacting with lipid membranes which in turn helps to understand why some known systems work better than others and aids the design of new particles and improvement of methods for preparing existing ones.

Multidrug resistant tumors-aimed theranostics on the basis of strong electrostatic attraction between resistant cells and nanomaterials

The gene expression of resistant cells usually raises the negative potential of cell membranes. Utilizing the strong electrostatic attraction of resistant cells with nanomaterials, multidrug resistance tumors-aimed theranostics is demonstrated.

Gold nanorod-encapsulated biodegradable polymeric matrix for combined photothermal and chemo-cancer therapy

PURPOSE

A biocompatible nanocomplex system co-encapsulated with gold nanorods (AuNRs) and doxorubicin (DOX) was investigated for its potentials on the combined photothermal- and chemotherapy.

MATERIALS AND METHODS

Hydrophobic AuNRs were synthesized by the hexadecyltrimethyl-ammonium bromide (CTAB)-mediated seed growth method, and then, they received two-step surface modifications of polyethylene glycol (PEG) and dodecane. The AuNR/DOX/poly(lactic-co-glycolic acid) (PLGA) nanocomplexes were prepared by emulsifying DOX, AuNR, and PLGA into aqueous polyvinyl alcohol solution by sonication. Human serum albumin (HSA) was used to coat the nanocomplexes to afford HSA/AuNR/DOX-PLGA (HADP). Size and surface potential of the HADP nanocomplexes were determined by using a Zetasizer. Cytotoxicity and cellular uptake of the HADP were analyzed by using MTT assay and flow cytometry, respectively. In vitro anticancer effects of the HADP were studied on various cancer cell lines. To assess the therapeutic efficacy, CT26 tumor-bearing mice were intravenously administered with HADP nanocomplexes and laser treatments, followed by monitoring of the tumor growth and body weight.

RESULTS

Size and surface potential of the HADP nanocomplexes were 245.8 nm and -8.6 mV, respectively. Strong photothermal effects were verified on the AuNR-loaded PLGA nanoparticles (NPs) in vitro. Rapid and repeated drug release from the HADP nanocomplexes was successfully achieved by near-infrared (NIR) irradiations. HSA significantly promoted cellular uptake of the HADP nanocomplexes to murine colon cancer cells as demonstrated by cell imaging and flow cytometric studies. By combining photothermal and chemotherapy, the HADP nanocomplexes exhibited strong synergistic anticancer effects in vitro and in vivo.

CONCLUSION

An NIR-triggered drug release system by encapsulating hydrophobic AuNR and DOX inside the PLGA NPs has been successfully prepared in this study. The HADP NPs show promising combined photothermal- and chemotherapeutic effects without inducing undesired side effects on a murine colon cancer animal model.

PEGylated hydrazided gold nanorods for pH-triggered chemo/photodynamic/photothermal triple therapy of breast cancer

Integration of multimodal therapies into one nanoplatform holds great promise to overcome the drawbacks of conventional single-modal therapy and pursues enhanced anticancer efficacy. Herein, we developed a PEGylated gold nanorods (GNRs)-based nanoplatform (GNRs-MPH^-ALA/DOX-PEG) with pH-responsive drug release property for triple-combined chemotherapy (CT), photodynamic therapy (PDT) and photothermal therapy (PTT) of breast cancer. GNRs were first decorated with mercaptopropionylhydrazide (MPH) and thiol-terminated monomethoxyl poly(ethylene glycol) (mPEG-SH) via Au-thiol linkage, and subsequently conjugated with chemotherapeutant doxorubicin (DOX) and pro-photosensitizer 5-aminolevulinic acid (ALA) through acid-liable hydrazone bonds between drugs and MPH molecules. The resulting nanoplatform GNRs-MPH^-ALA/DOX-PEG exhibited excellent stability in physiological solutions and pH-responsive DOX and ALA release behaviors. In vitro studies showed that GNRs-MPH^-ALA/DOX-PEG could efficiently enter human breast cancer MCF-7 cells and release DOX and ALA into cytoplasm. Furthermore, DOX could locate in the cell nucleus and ALA was productively metabolized into protoporphyrin IX (PpIX). Upon near-infrared (NIR) irradiation, PpIX produced enough reactive oxygen species for PDT and meanwhile GNRs could efficiently induce hyperthermia for PTT. Compared with single CT and dual-modal CT/PDT or CT/PTT treatment, the triple-combined CT/PDT/PTT treatment could more efficiently kill MCF-7 cells via a superadditive antitumor effect. Furthermore, the circulation half-life of GNRs-MPH^-ALA/DOX-PEG in the blood was as long as approximately 52 min and it exhibited a tumor accumulation of 3.3%. The triple-combined CT/PDT/PTT treatment could completely suppress tumor growth without obvious systemic toxicity. Our study paves a new avenue for multimodal therapy of breast cancer. STATEMENT OF SIGNIFICANCE: The development of a simple but effective strategy to construct a versatile nanoplatform for multi-combined therapy still remains an enormous challenge. In this work, we developed a novel and simple nanoplatform GNRs-MPH^-ALA/DOX-PEG with pH-responsive drug release for triple-combined chemotherapy (CT), photodynamic therapy (PDT) and photothermal therapy (PTT) of breast cancer. The nanoplatform could be efficiently internalized by MCF-7 cells. The intracellular GNRs-MPH^-ALA/DOX-PEG could release DOX for CT, induce hyperthermia for PTT and generate high levels of ROS for PTT. Compared with single CT and dual-modal CT/PDT or CT/PTT treatments, the triple-combined CT/PDT/PTT treatment could more efficiently kill MCF-7 cells via a superadditive antitumor effect. Furthermore, upon triple-combined CT/PDT/PTT treatment, the tumor growth was completely suppressed without obvious systemic toxicity.

Gold Nanorod-Based Nanohybrids for Combinatorial Therapeutics

In this work, multifunctional nanocarriers consisting of poly(sodium-4-styrenesulfonate) (PSS)/doxorubicin (DOXO)/poly-l-lysine hydrobromide (PLL)/hyaluronic acid (HA)-coated and (PSS/DOXO/PLL)₂/HA-coated gold nanorods were assembled by the layer-by-layer technique with the aims of coupling the plasmonic photothermal properties of the metal nanoparticles for plasmonic hyperthermia and the chemoaction of drug DOXO for potential intended combinatorial cancer therapeutics in the future as well as providing different strategies for the controlled and sustained release of the cargo drug molecules. To do that, DOXO could be successfully loaded onto the hybrid nanoconstructs through electrostatic interactions with high efficiencies of up to ca. 78.3 ± 6.9% for the first formed drug layer and 56 ± 13% for the second one, with a total efficiency for the whole system [(PSS/DOXO/PLL)₂/HA-coated NRs] of ca. 65.7 ± 1.4%. Nanohybrid internalization was observed to be enhanced by the outer HA layer, which is able to target the CD44 receptors widely overexpressed in some types of cancers as lung, breast, or ovarian ones. Hence, these nanohybrid systems might be versatile nanoplatforms to simultaneously deliver sufficient heat for therapeutic plasmonic hyperthermia and the anticancer drug. Two controlled mechanisms were proposed to modulate the release of the chemodrug, one by means of the enzymatic degradable character of the PLL layer and another by the modulation of the interactions between the polymeric layers through the exploitation of the optical properties of the hybrid particles under near infrared (NIR) laser irradiation. The combination of this bimodal therapeutic approach exerted a synergistic cytotoxic effect on both HeLa and MDA-MB-231 cancer cells in vitro. Cell death mechanisms were also analyzed, elucidating that plasmonic photothermal therapy induces cell necrosis, whereas DOXO activates the cell apoptotic pathway. Therefore, the present NIR laser-induced targeted cancer thermo/chemotherapy represents a novel targeted anticancer strategy with easy control on demand and suitable therapeutic efficacy.

Tat-functionalized Ag-Fe3O4 nano-composites as tissue-penetrating vehicles for tumor magnetic targeting and drug delivery

In this paper, we prepared a dual functional system based on dextrin-coated silver nanoparticles which were further attached with iron oxide nanoparticles and cell penetrating peptide (Tat), producing Tat-modified Ag-Fe₃O₄ nanocomposites (Tat-FeAgNPs). To load drugs, an –SH containing linker, 3-mercaptopropanohydrazide, was designed and synthesized. It enabled the silver carriers to load and release doxorubicin (Dox) in a pH-sensitive pattern. The delivery efficiency of this system was assessed in vitro using MCF-7 cells, and in vivo using null BalB/c mice bearing MCF-7 xenograft tumors. Our results demonstrated that both Tat and externally applied magnetic field could promote cellular uptake and consequently the cytotoxicity of doxorubicin-loaded nanoparticles, with the IC₅₀ of Tat-FeAgNP-Dox to be 0.63 µmol/L. The in vivo delivery efficiency of Tat-FeAgNP carrying Cy5 to the mouse tumor was analyzed using the in vivo optical imaging tests, in which Tat-FeAgNP-Cy5 yielded the most efficient accumulation in the tumor (6.7±2.4% ID of Tat-FeAgNPs). Anti-tumor assessment also demonstrated that Tat-FeAgNP-Dox displayed the most significant tumor-inhibiting effects and reduced the specific growth rate of tumor by 29.6% (P = 0.009), which could be attributed to its superior performance in tumor drug delivery in comparison with the control nanovehicles.

Glutathione detonated and pH responsive nano-clusters of Au nanorods with a high dose of DOX for treatment of multidrug resistant cancer

Effects of nanosized drug delivery systems on cancer are often compromised due to their low drug loadings, premature drug release and multi-drug resistance (MDR). Herein, we reported a glutathione detonated and pH responsive nano-cluster of Au nanorods (AuNRs) with chemotherapeutic doxorubicin (DOX) and pre-chemosensitizer polycurcumin to treat MCF-7/ADR cells. The nano-cluster was prepared by self-assembling of AuNRs conjugated with DOX and amphiphilic poly(curcumin-co-dithiodipropionic acid)-b-biotinylated poly(ethylene glycol) via an emulsion/solvent evaporation technique, termed AuNR Cluster. The AuNR Cluster had a high drug loading (31.5% DOX), presenting much better aqueous solubility and stability at physiological pH than their individual AuNRs. The AuNR Cluster could be detonated to be their individual AuNRs at an intracellular concentration level of glutathione (GSH) (5 mM) and triggered to release DOX at an acidic pH (pH 6.8 or 5.0), which effectively facilitated cellular uptake of DOX (607 vs 356 a.u. for AuNRs at 12 h) and inhibited DOX efflux (471.33 vs 39.17 a.u. for free DOX at 24 h). The IC₅₀ value of DOX against MCF-7/ADR cells for AuNR Cluster was 4.15 µg/mL, much lower than that for free DOX (90.97 µg/mL). The AuNR Cluster took much more photothermal effects than their corresponding AuNRs and presented enhanced anti-tumor effect (IC₅₀: 2.61 µg/mL) under 808 nm laser irradiation.

STATEMENT OF SIGNIFICANCE

Nano-sized drug delivery systems for anti-MDR cancer is still a challenging task. Herein, AuNR Cluster was self-assembled by individual AuNRs via emulsion/solvent evaporation technique, having a structure consisting of hydrophobic DOX/PCDA-AuNR core and hydrophilic biotin-PEG chain shell. AuNR Cluster is detonated to disintegrate and yield its individual AuNRs at an intracellular concentration level of glutathione (5 mM) and triggered to release DOX at an acidic pH (6.8 or 5.0). In comparison with its individual AuNRs, AuNR Cluster has better water solubility and stability, greater photothermal effects under NIR irradiation, bigger cytotoxicity against MCF-7/ADR cells. AuNR Cluster is expected to be a potential nanomedicine for treatment of MDR cancer.

pH-Sensitive Multiligand Gold Nanoplatform Targeting Carbonic Anhydrase IX Enhances the Delivery of Doxorubicin to Hypoxic Tumor Spheroids and Overcomes the Hypoxia-Induced Chemoresistance

Hypoxia is a common feature of solid tumors contributing to resistance to chemotherapy. Selective delivery of chemotherapeutic drugs to hypoxic tumor niche remains an unsolved issue. For this purpose, we constructed a gold nanoplatform targeting carbonic anhydrase IX (CA IX) epitope, which is overexpressed in hypoxic tumor cells versus in normal tissues. We designed compatible low-molecular weight carbonic anhydrase inhibitor (CAI) ligands and doxorubicin (Dox) ligands and optimized protocols for efficient decoration of gold nanoparticles (Au NPs) to achieve both good targeting ligand density and optimum drug loading, while preserving colloidal stability. The optimized Dox-HZN-DTDP@Au NPs-LA-PEG2000-CAI (THZN) nanoplatform was proved to be very efficient toward killing HT-29 tumor cells, especially under hypoxic conditions, as compared with the nontargeting nanoplatform. This also mediated the effective release of doxorubicin in the lysosomes following internalization, as revealed by confocal microscopy. Furthermore, using tumor spheroids as a representative model for hypoxic solid tumors, our THZN nanoplatform enhanced the selective delivery of doxorubicin up to 2.5 times and minimized chemoresistance, showing better tumor drug penetration as compared to that in free drug treatment. Our technology is the first CA IX-targeting gold nanoplatform for efficient delivery of doxorubicin to hypoxic tumors in a controlled fashion, with the perspective to improve the therapy of solid tumors and minimize chemoresistance.

Endogenous pH-responsive nanoparticles with programmable size changes for targeted tumor therapy and imaging applications

Nanotechnology-based antitumor drug delivery systems, known as nanocarriers, have demonstrated their efficacy in recent years. Typically, the size of the nanocarriers is around 100 nm. It is imperative to achieve an optimum size of these nanocarriers which must be designed uniquely for each type of delivery process. For pH-responsive nanocarriers with programmable size, changes in pH (~6.5 for tumor tissue, ~5.5 for endosomes, and ~5.0 for lysosomes) may serve as an endogenous stimulus improving the safety and therapeutic efficacy of antitumor drugs. This review focuses on current advanced pH-responsive nanocarriers with programmable size changes for anticancer drug delivery. In particular, pH-responsive mechanisms for nanocarrier retention at tumor sites, size reduction for penetrating into tumor parenchyma, escaping from endo/lysosomes, and swelling or disassembly for drug release will be highlighted. Additional trends and challenges of employing these nanocarriers in future clinical applications are also addressed.

Recent biomedical applications of gold nanoparticles: A review

Recent advances in nanotechnology are as a result of the development of engineered nanoparticles. Efficiently, metallic nanoparticles have been widely exploited for biomedical application and among them, gold nanoparticles (AuNPs) are highly remarkable. Consequent upon their significant nature, spherical and gold nanorods (Au NRs) nanoparticles attract extreme attention. Their intrinsic features such as optical, electronic, physicochemical and, surface plasmon resonance (SPR); which can be altered by changing the characterizations of particles such as shape, size, aspect ratio, or environment; ease of synthesis and functionalization properties have resulted to various applications in different fields of biomedicine such as sensing, targeted drug delivery, imaging, photothermal and photodynamic therapy as well as the modulation of two or three applications. This article reviewed the popular AuNPs synthesis methods and mentioned their established applications in various demands, especially in biological sensing.