Synthesis and characterization of a multifunctional gold-doxorubicin nanoparticle system for pH triggered intracellular anticancer drug release

Modified frankincense resin stabilized gold nanoparticles for enhanced antioxidant and synergetic activity in in-vitro anticancer studies

For the first time, Frankincense resin (FR) has been carboxymethylated to produce CMFR - AuNPs and the conjugate was utilized for the Doxorubicin drug loading. The carboxymethylation of the carboxylic, phenolic, and hydroxyl functional groups of FR has been developed into carboxymethylated Frankincense resin (CMFR). A novel CMFR-AuNPs was synthesized using the developed CMFR as a stabilizing and reducing agent. The antibacterial, antioxidant, and in-vitro anticancer activities were investigated by using CMFR-AuNPs and CMFR - AuNPs@DOX. CMFR-AuNPs demonstrated antioxidative properties by quenching DPPH radicals effectively. CMFR-AuNPs and DOX@CMFR-AuNPs demonstrated strong antibacterial activity against K. pneumoniae, S. aureus, B. subtilis, and E. coli. The cell viability was tested for CMFR -AuNPs at various concentrations of Dox-loaded CMFR -AuNPs (CMFR-AuNPs + Dox1, CMFR-AuNPs + Dox 2, & CMFR-AuNPs + Dox 3). The highest inhibition was observed on MCF-7 and HeLa cell lines using CMFR-AuNPs + Dox 3, respectively. Various techniques such as UV, FTIR, TGA, XRD, SEM, EDAX and TEM were used to characterize the designed CMFR and CMFR-AuNPs. After carboxy methylation, the amorphous nature of FR changed to crystallinity, as reflected in the XRD spectra. The XRD spectrum of the CMFR- AuNPs showed FCC structure due to the involvement of hydroxyl and carboxylic functional groups of CMFR strongly bound with the AuNPs. TGA results revealed that the CMFR is thermally more stable than FR. TEM revealed that CMFR - AuNPs were well dispersed, spherical, and hexagonal with an average diameter of 7 to 10 nm, while the size of doxorubicin loaded (DOX@CMFR-AuNPs) AuNPs was 11 to 13 nm. Green CMFR-AuNPs have the potential to enhance the drug loading and anticancer efficacy of drugs.

Advances in stimuli-responsive gold nanorods for drug-delivery and targeted therapy systems

In recent years, the use of gold nanorods (AuNRs) has garnered considerable attention in biomedical applications due to their unique optical and physicochemical properties. They have been considered as potential tools for the advanced treatment of diseases by various stimuli such as magnetic fields, pH, temperature and light in the fields of targeted therapy, imaging and drug delivery. Their biocompatibility and tunable plasmonic properties make them a versatile platform for a range of biomedical applications. While endogenous stimuli have limited cargo delivery control at specific sites, exogenous stimuli are a more favored approach despite their circumscribed penetration depth for releasing the cargo at the specific target. Dual/multi-stimuli responsive AuNTs can be triggered by multiple stimuli for enhanced control and specificity in biomedical applications. This review provides to provide a summary of the biomedical applications of stimuli-responsive AuNRs, including their endogenous and exogenous properties, as well as their dual/multi-functionality and potential for clinical delivery. This review provides a comprehensive review on the improvement of therapeutic efficacy and the effective control of drug release with AuNRs, highlights AuNRs design strategies in recent years, discusses the advantages or challenges so far in the field of AuNRs. Finally, we have addressed the clinical translation bio-integrated nanoassemblies (CTBNs) in this field.

Synthesis and toxicity assessment of Coffea arabica extract-derived gold nanoparticles loaded with doxorubicin in lung cancer cell cultures

Cancer is the second leading cause of death worldwide, despite the many treatments available, cancer patients face side effects that reduce their quality of life. Therefore, there is a need to develop novel strategies to increase the efficacy of treatments. In this study, gold nanoparticles obtained by green synthesis with Coffea arabica green bean extract were loaded with Doxorubicin, (a highly effective but non-specific drug) by direct interaction and using commercial organic ligands that allow colloidal dispersion at physiological and tumor pH. Conjugation of these components resulted in stable nanohybrids at physiological pH and a tumor pH release dependent, with a particle size less than 40 nm despite having the ligands and Doxorubicin loaded on their surface, which gave them greater specificity and cytotoxicity in H69 tumor cells.

Fabrication of hyaluronic acid-altered gold complex delivery for head and neck squamous cell carcinoma therapy with high antitumor efficacy and low in vivo toxicity

The use of multifunctional nanomedicines in the treatment of tumors is gaining popularity. Here, we constructed a nanodrug delivery system (HA/Au-PDA@CZT) that targets tumors and responds to pH and near-infrared (NIR) dual stimuli. By precisely interacting with an overexpressed CD44 receptor in specific cancer cells, hyaluronic acid (HA) is coated on the Au-PDA NP surface for tumor-targeting abilities. When exposed to NIR radiation, polydopamine (PDA) and gold nanoshells exhibit exceptional photothermal performance that has the potential to both accelerate and kill HLAC 78 head and neck squamous cell carcinoma cells. Antitumor investigations conducted in vivo and in vitro demonstrated that nanomedicine had remarkable synergistic benefits with chemotherapy and photothermal treatment. Only 25.2% of the cells in the HA/Au-PDA@CZT with a NIR irradiation group were viable. Any group's lowest tumor volume was shown in the tumor mice subjected to HA/Au-PDA@CZT with NIR at 0.3 ± 0.1. Consequently, for synergistic chemo-photothermal therapy, our logically designed nanoplatform would be the potential for a head and neck squamous tumor-targeting drug delivery system.

Review of Advances in Coating and Functionalization of Gold Nanoparticles: From Theory to Biomedical Application

Nanoparticles, especially gold nanoparticles (Au NPs) have gained increasing interest in biomedical applications. Used for disease prevention, diagnosis and therapies, its significant advantages in therapeutic efficacy and safety have been the main target of interest. Its application in immune system prevention, stability in physiological environments and cell membranes, low toxicity and optimal bioperformances are critical to the success of engineered nanomaterials. Its unique optical properties are great attractors. Recently, several physical and chemical methods for coating these NPs have been widely used. Biomolecules such as DNA, RNA, peptides, antibodies, proteins, carbohydrates and biopolymers, among others, have been widely used in coatings of Au NPs for various biomedical applications, thus increasing their biocompatibility while maintaining their biological functions. This review mainly presents a general and representative view of the different types of coatings and Au NP functionalization using various biomolecules, strategies and functionalization mechanisms.

A Green Synthesis of Au-Ag Alloy Nanoparticles using Polydopamine Chemistry: Evaluation of their Anticancer Potency Towards Both MCF-7 Cells and their Cancer Stem Cells Subgroup

BACKGROUND

Limited chemotherapy efficacy and cancer stem cells (CSCs)-induced therapeutic resistance are major difficulties for tumour treatment. Adopting more efficient therapies to eliminate bulk-sensitive cancer cells and resistant CSCs is urgently needed.

METHODS

Based on the potential and functional complementarity of gold and silver nanoparticles (AuNPs or AgNPs) on tumour treatment, bimetallic NPs (alloy) have been synthesized to obtain improved or even newly emerging bioactivity from a combination effect. This study reported a facile, green and economical preparation of Au-Ag alloy NPs using biocompatible polydopamine (PDA) as a reductant, capping, stabilizing and hydrophilic agent.

RESULTS

These alloy NPs were quasi-spherical with rough surfaces and recorded in diameters of 80 nm. In addition, these alloy NPs showed good water dispersity, stability and photothermal effect. Compared with monometallic counterparts, these alloy NPs demonstrated a dramatically enhanced cytotoxic/pro-apoptotic/necrotic effect towards bulk-sensitive MCF-7 and MDA-MB-231 cells. The underlying mechanism regarding the apoptotic action was associated with a mitochondria-mediated pathway, as evidenced by Au3+/Ag+ mediated Mitochondria damage, ROS generation, DNA fragmentation and upregulation of certain apoptotic-related genes (Bax, P53 and Caspase 3). Attractively, these Au-Ag alloy NPs showed a remarkably improved inhibitory effect on the mammosphere formation capacity of MCF-7 CSCs.

CONCLUSION

All the positive results were attributed to incorporated properties from Au, Ag and PDA, the combination effect of chemotherapy and photothermal therapy and the nano-scaled structure of Au-Ag alloy NPs. In addition, the high biocompatibility of Au-Ag alloy NPs supported them as a good candidate in cancer therapy.

An application of carbohydrate polymers-based surface-modified gold nanoparticles for improved target delivery to liver cancer therapy - A systemic review

Gold nanoparticles have been broadly investigated as cancer diagnostic and therapeutic agents. Gold nanoparticles are a favorable drug delivery vehicle with their unique subcellular size and good biocompatibility. Chitosan, agarose, fucoidan, porphyran, carrageenan, ulvan and alginate are all examples of biologically active macromolecules. Since they are biocompatible, biodegradable, and irritant-free, they find extensive application in biomedical and macromolecules. The versatility of these compounds is enhanced because they are amenable to modification by functional groups like sulfation, acetylation, and carboxylation. In an eco-friendly preparation process, the biocompatibility and targeting of GNPs can be improved by functionalizing them with polysaccharides. This article provides an update on using carbohydrate-based GNPs in liver cancer treatment, imaging, and drug administration. Selective surface modification of several carbohydrate types and further biological uses of GNPs are focused on.

Nanoparticles in Medicine: Current Status in Cancer Treatment

Cancer is still a leading cause of deaths worldwide, especially due to those cases diagnosed at late stages with metastases that are still considered untreatable and are managed in such a way that a lengthy chronic state is achieved. Nanotechnology has been acknowledged as one possible solution to improve existing cancer treatments, but also as an innovative approach to developing new therapeutic solutions that will lower systemic toxicity and increase targeted action on tumors and metastatic tumor cells. In particular, the nanoparticles studied in the context of cancer treatment include organic and inorganic particles whose role may often be expanded into diagnostic applications. Some of the best studied nanoparticles include metallic gold and silver nanoparticles, quantum dots, polymeric nanoparticles, carbon nanotubes and graphene, with diverse mechanisms of action such as, for example, the increased induction of reactive oxygen species, increased cellular uptake and functionalization properties for improved targeted delivery. Recently, novel nanoparticles for improved cancer cell targeting also include nanobubbles, which have already demonstrated increased localization of anticancer molecules in tumor tissues. In this review, we will accordingly present and discuss state-of-the-art nanoparticles and nano-formulations for cancer treatment and limitations for their application in a clinical setting.

Targeted Doxorubicin-Loaded Dendronized Gold Nanoparticles

Dendronized nanoparticles, also called nanoparticle-cored dendrimers, combine the advantages of nanoparticles and dendrimers. These very stable and polyvalent nanoparticles can be used for diverse applications. One such application is drug delivery, because the dendrons can enhance the density of the payload. In this report, we describe the design of multifunctional gold nanoparticles (AuNPs) coated with poly(propylene imine) (PPI) dendrons that contain both prostate cancer active targeting and chemotherapeutic drugs. The PPI dendron is a good candidate for the design of drug delivery vehicles because of its ability to induce a proton sponge effect that will enhance lysosomal escape and intracellular therapeutic delivery. The chemotherapeutic drug used is doxorubicin (DOX), and it was linked to the dendron through a hydrazone acid-sensitive bond. Subsequent acidification of the AuNP system to a pH of 4-5 resulted in the release of 140 DOX drugs per nanoparticles. In addition, the PPI dendron was conjugated via "click" chemistry to an EphA2-targeting antibody fragment that has been shown to target prostate cancer cells. In vitro cell viability assays revealed an IC50 of 0.9 nM for the targeted DOX-bearing AuNPs after 48 h incubation with PC3 cells. These results are very promising upon optimization of the system.

Gold Nanoparticles: Construction for Drug Delivery and Application in Cancer Immunotherapy

Cancer immunotherapy is an innovative treatment strategy to enhance the ability of the immune system to recognize and eliminate cancer cells. However, dose limitations, low response rates, and adverse immune events pose significant challenges. To address these limitations, gold nanoparticles (AuNPs) have been explored as immunotherapeutic drug carriers owing to their stability, surface versatility, and excellent optical properties. This review provides an overview of the advanced synthesis routes for AuNPs and their utilization as drug carriers to improve precision therapies. The review also emphasises various aspects of AuNP-based immunotherapy, including drug loading, targeting strategies, and drug release mechanisms. The application of AuNPs combined with cancer immunotherapy and their therapeutic efficacy are briefly discussed. Overall, we aimed to provide a recent understanding of the advances, challenges, and prospects of AuNPs for anticancer applications.

Hyaluronic acid-engineered Bcl-2 inhibitor nanocrystals for site-specific delivery to breast tumor cells

Aim: This investigation aims to repurpose venetoclax using hyaluronic acid-coated venetoclax nanocrystals (HA-VEN-NCs) to target breast cancer. Materials & methods: An antisolvent precipitation method was used to fabricate the nanocrystals and optimize them using central composite design. Hyaluronic acid (HA)-coated and -uncoated nanocrystals were compared in terms of in vitro drug release, cell line studies, CD44-expressing breast tumor cell binding capability and anticancer activity. Results: HA-VEN-NCs and venetoclax nanocrystals (VEN-NCs) showed pH-responsive drug-release behavior, exhibiting sustained release at pH 6.8. Our extensive in vitro cell line investigation showed that HA-VEN-NCs efficiently bind to CD44-expressing breast tumor cells and possess excellent anticancer activity (IC50: 2.00 μg/ml) compared with VEN-NCs. Conclusion: Our findings anticipate that HA-VEN-NCs could serve as valuable nanoplatforms for cancer treatments in the future.

pH-Sensitive Gold Nanorods for Non-Steroidal Anti-Inflammatory Drugs (NSAIDs) Delivery and DNA-Binding Studies

A facile experimental protocol for the synthesis of poly(ethylene glycol)-modified (PEGylated) gold nanorods (AuNRs@PEG) is presented as well as an effective drug loading procedure using the non-steroidal anti-inflammatory drug (NSAID) naproxen (NAP). The interaction of AuNRs@PEG and drug-loaded AuNRs (AuNRs@PEG@NAP) with calf-thymus DNA was studied at a diverse temperature revealing different interaction modes; AuNRs@PEG may interact via groove-binding and AuNRs@PEG@NAP may intercalate to DNA-bases. The cleavage activity of the gold nanoparticles for supercoiled circular pBR322 plasmid DNA was studied by gel electrophoresis while their affinity for human and bovine serum albumins was also evaluated. Drug-release studies revealed a pH-sensitive behavior with a release up to a maximum of 24% and 33% NAP within the first 180 min at pH = 4.2 and 6.8, respectively. The cytotoxicity of AuNRs@PEG and AuNRs@PEG@NAP was evaluated against MCF-7 and MDA-MB-231 breast cancer cell lines. The development of AuNRs as an efficient non-steroidal anti-inflammatory drugs (NSAIDs) delivery system for chemotherapy is still in its infancy. The present work can shed light and inspire other research groups to work in this direction.

Gold Nanosystems Covered with Doxorubicin/DNA Complexes: A Therapeutic Target for Prostate and Liver Cancer

Different gold nanosystems covered with DNA and doxorubicin (Doxo) were designed and synthesized for cancer therapy, starting from Au@16-Ph-16 cationic nanoparticles and DNA-Doxo complexes prepared under saturation conditions. For the preparation of stable, biocompatible, and small-sized compacted Au@16-Ph-16/DNA-Doxo nanotransporters, the conditions for the DNA-Doxo compaction process induced by gold nanoparticles were first explored using fluorescence spectroscopy, circular dichroism and atomic force microscopy techniques. The reverse process, which is fundamental for Doxo liberation at the site of action, was found to occur at higher C_Au@16-Ph-16 concentrations using these techniques. Zeta potential, dynamic light scattering and UV-visible spectroscopy reveal that the prepared compacted nanosystems are stable, highly charged and of adequate size for the effective delivery of Doxo to the cell. This fact is verified by in vitro biocompatibility and internalization studies using two prostate cancer-derived cell lines (LNCaP and DU145) and one hepatocellular carcinoma-derived cell line (SNU-387), as well as a non-tumor prostate (PNT2) cell line and a non-hepatocarcinoma hepatoblastoma cell line (Hep-G2) model used as a control in liver cells. However, the most outstanding results of this work are derived from the use of the C_I+N_I combined treatments which present strong action in cancer-derived cell lines, while a protective effect is observed in non-tumor cell lines. Hence, novel therapeutic targets based on gold nanoparticles denote high selectivity compared to conventional treatment based on free Doxo at the same concentration. The results obtained show the viability of both the proposed methodology for internalization of compacted nanocomplexes inside the cell and the effectiveness of the possible treatment and minimization of side effects in prostate and liver cancer.

Functionalized Silver and Gold Nanomaterials with Diagnostic and Therapeutic Applications

The functionalization of nanomaterials with suitable capping ligands or bioactive agents is an interesting strategy in designing nanosystems with suitable applicability and biocompatibility; the physicochemical and biological properties of these nanomaterials can be highly improved for biomedical applications. In this context, numerous explorations have been conducted in the functionalization of silver (Ag) and gold (Au) nanomaterials using suitable functional groups or agents to design nanosystems with unique physicochemical properties such as excellent biosensing capabilities, biocompatibility, targeting features, and multifunctionality for biomedical purposes. Future studies should be undertaken for designing novel functionalization tactics to improve the properties of Au- and Ag-based nanosystems and reduce their toxicity. The possible release of cytotoxic radicals or ions, the internalization of nanomaterials, the alteration of cellular signaling pathways, the translocation of these nanomaterials across the cell membranes into mitochondria, DNA damages, and the damage of cell membranes are the main causes of their toxicity, which ought to be comprehensively explored. In this study, recent advancements in diagnostic and therapeutic applications of functionalized Au and Ag nanomaterials are deliberated, focusing on important challenges and future directions.

Green Synthesis of Gold Nanoparticles and Study of Their Inhibitory Effect on Bulk Cancer Cells and Cancer Stem Cells in Breast Carcinoma

Chemo-resistance from cancer stem cells (CSCs) subpopulation is a current issue in cancer treatment. It is important to select alternative therapies to efficiently eradicate both bulk cancer cells and CSCs. Here, gold nanoparticles (AuNPs) have been selected regarding their biocompatibility, facile and controllable synthesis, potent anti-cancer activity and photothermal conversion performance. We reported a green synthesis of functionalized AuNPs using hyaluronic acid (HA) as a reductant, capping, stabilizing and hydrophilic substance. The resultant AuNPs were spherical-shaped with an average diameter of around 30 nm. These AuNPs displayed improved physico-chemical (yield, stability, photothermal effect) and biological properties (cellular uptake, cytotoxicity and apoptotic effect) against bulk MDA-MB-231 cells, in comparison with other organic anti-cancer drugs. The intensified bioactivity was dependent on a mitochondria-mediated cascade, reflected by the damage in mitochondria, oxidative stress, intensified Caspase 3 activity and increased/decreased expression of certain pro-apoptotic (Bax, P53, Caspase 3)/anti-apoptotic (Bcl-2) genes. Moreover, these AuNPs posed a dramatically improved inhibitory effect in cell viability and self-renewable capacity on CSC subpopulation. All the results were attributed from the nano-scaled structure of AuNPs and combined effect from NIR-induced hyperthermia. In addition, the biocompatible nature of these AuNPs supported them to be a potential candidate in the development of novel chemotherapeutic drugs.

Significance of Capping Agents of Colloidal Nanoparticles from the Perspective of Drug and Gene Delivery, Bioimaging, and Biosensing: An Insight

The over-growth and coagulation of nanoparticles is prevented using capping agents by the production of stearic effect that plays a pivotal role in stabilizing the interface. This strategy of coating the nanoparticles’ surface with capping agents is an emerging trend in assembling multipurpose nanoparticles that is beneficial for improving their physicochemical and biological behavior. The enhancement of reactivity and negligible toxicity is the outcome. In this review article, an attempt has been made to introduce the significance of different capping agents in the preparation of nanoparticles. Most importantly, we have highlighted the recent progress, existing roadblocks, and upcoming opportunities of using surface modified nanoparticles in nanomedicine from the drug and gene delivery, bioimaging, and biosensing perspectives.

Gold Nanoparticle-Decorated Drug Nanocrystals for Enhancing Anticancer Efficacy and Reversing Drug Resistance Through Chemo-/Photothermal Therapy

Limited chemotherapeutic efficiency, drug resistance, and side effects are primary obstacles for cancer treatment. The development of co-delivery systems with synergistic treatment modes should be a promising strategy. Here, we fabricated a multifunctionalized nanocarrier with a combination of chemotherapeutic agents and gold nanoparticles (AuNPs), which could integrate chemo-photothermal therapy, thus enhancing overall anticancer efficacy, sensitizing drug-resistant cancer cells, and diminishing cancer stem cells (CSCs). To be specific, camptothecin nanocrystals (CPT NCs) were prepared as a platform, on the surface of which AuNPs were decorated and a hyaluronic acid layer acted as capping, stabilizing, targeting, and hydrophilic agents for CPT NCs, and reducing agents for AuNPs, providing a bridge connecting AuNPs to CPT. These AuNP-decorated CPT NCs exhibited good physico-chemical properties such as optimal sizes, payload, stability, and photothermal efficiency. Compared to other CPT formulations, they displayed considerably improved biocompatibility, selectivity, intracellular uptake, cytotoxicity, apoptosis induction activity, Pgp inhibitory capability, and anti-CSC activity, owing to a synergistic/cooperative effect from AuNPs, CPT, near-infrared treatment, pH/photothermal-triggered drug release, and nanoscaled structure. A mitochondrial-mediated signaling pathway is the underlying mechanism for cytotoxic and apoptotic effects from AuNP-decorated CPT NCs, in terms of mitochondrial dysfunction, intensified oxidative stress, DNA fragmentation, caspase 3 activation, upregulation of proapoptotic genes such as p53, Bax, and caspase 3, and lower levels of antiapoptotic Bcl-2.

A New Gold Nanoparticles and Paclitaxel Co-Delivery System for Enhanced Anti-Cancer Effect Through Chemo-Photothermal Combination

Limited chemotherapeutic efficiency, drug resistance and side effect are primary obstacles for cancer treatment. The development of co-delivery system with synergistic treatment modes should be a promising strategy. Here, we fabricated a multi-functionalized nanocarrier with a combination of chemotherapeutic agent and gold nanoparticles (AuNPs), which could integrate chemo-photothermal therapy and improve entire anti-cancer index. Particularly, Paclitaxel nanocrystals (PTX NC) were first fabricated as a platform, on surface of which AuNPs were decorated and polydopamine (PDA) layer act as capping, stabilizing and hydrophilic agents for PTX NC, providing a bridge connecting AuNPs to PTX. These AuNPs decorated PTX NC exhibited good physico-chemical properties like optimal sizes, stability and photothermal efficiency. Compared to other PTX formulations, they displayed considerably improved biocompatibility, selectivity, intracellular uptake, cytotoxicity, apoptosis induction activity and P-glycoprotein (Pgp) inhibitory capability, owing to a synergistic/ cooperative effect from AuNPs, PTX and NIR treatment, photothermal-triggered drug release and nano-scaled structure. Mitochondria-mediated signaling pathway is underlying mechanism for cytotoxic and apoptotic effect from AuNPs decorated PTX NC, in terms of Mitochondria damage, a loss of Mitochondrial membrane potential, intensified oxidative stress, DNA breakage, Caspase 3 activation, up-regulated expression in pro-apoptotic genes like p53, Caspase 3 and Bax and down-regulated level in anti-apoptotic gene like Bcl-2.

Fluorescent Silica Nanoparticles Targeting Mitochondria: Trafficking in Myeloid Cells and Application as Doxorubicin Delivery System in Breast Cancer Cells

Fluorescent silica nanoparticles (SiNPs) appear to be a promising imaging platform, showing a specific subcellular localization. In the present study, we first investigated their preferential mitochondrial targeting in myeloid cells, by flow cytometry, confocal microscopy and TEM on both cells and isolated mitochondria, to acquire knowledge in imaging combined with therapeutic applications. Then, we conjugated SiNPs to one of the most used anticancer drugs, doxorubicin (DOX). As an anticancer agent, DOX has high efficacy but also an elevated systemic toxicity, causing multiple side effects. Nanostructures are usually employed to increase the drug circulation time and accumulation in target tissues, reducing undesired cytotoxicity. We tested these functionalized SiNPs (DOX-NPs) on breast cancer cell line MCF-7. We evaluated DOX-NP cytotoxicity, the effect on the cell cycle and on the expression of CD44 antigen, a molecule involved in adhesion and in tumor invasion, comparing DOX-NP to free DOX and stand-alone SiNPs. We found a specific ability to release a minor amount of CD44+ extracellular vesicles (EVs), from both CD81 negative and CD81 positive pools. Modulating the levels of CD44 at the cell surface in cancer cells is thus of great importance for disrupting the signaling pathways that favor tumor progression.

Hyaluronic Acid Stabilized Doxorubicin Nano-Precipitations for Osteosarcoma Treatment

Doxorubicin (Dox) is a wide-spectrum drug to treat different kinds of cancers. However, in clinical practice, Dox usually showed untargeted distributions to the other organs, which can cause serious side effects, such as cardiotoxity. Herein, the formulation of Dox into nanoparticles is critical to enhance its distribution to tumors. Herein, we used polysaccharide, hyaluronic acid, to stabilize the Dox to form nano-precipitations (PD NPs) for the therapy of osteosarcoma. The PD NPs showed enhanced drug accumulation to tumor cells and realized better anticancer effects than free drugs.

Novel Green Approaches for the Preparation of Gold Nanoparticles and Their Promising Potential in Oncology

The difficulty of achieving targeted drug delivery following administration of currently marketed anticancer therapeutics is a still a concern. Metallic nanoparticles (NPs) developed through nanotechnology breakthroughs appear to be promising in this regard. Research studies pertaining to gold NPs have indicated their promising applicability in cancer diagnosis, drug delivery and therapy. These NPs have also recently paved the path for precise drug delivery and site-specific targeting. Our review paper thus highlights the scope and impact of biogenetically generated gold nanoparticles (NPs) in cancer therapy. In a critical, constructive, and methodical manner, we compare the advantages offered by gold NPs over other metal NPs. Moreover, we also focus on novel ‘greener’ strategies that have been recently explored for the preparation of gold NPs and shed light on the disadvantages of conventional NP synthesis routes. Future prospects pertaining to the use of gold NPs in oncotherapy and domains that require further investigation are also addressed.

Organic/Inorganic Self-Assembled Hybrid Nano-Architectures for Cancer Therapy Applications

Since the conceptualization of nanomedicine, numerous nanostructure-mediated drug formulations have progressed into clinical trials for treating cancer. However, recent clinical trial results indicate such kind of drug formulations has a limited improvement on the antitumor efficacy. This is due to the biological barriers associated with those formulations, for example, circulation stability, extravasation efficiency in tumor, tumor penetration ability, and developed multi-drug resistance. When employing for nanomedicine formulations, pristine organic-based and inorganic-based nanostructures have their own limitations. Accordingly, organic/inorganic (O/I) hybrids have been developed to integrate the merits of both, and to minimize their intrinsic drawbacks. In this context, the recent development in O/I hybrids resulting from a self-assembly strategy will be introduced. Through such a strategy, organic and inorganic building blocks can be self-assembled via either chemical covalent bonds or physical interactions. Based on the self-assemble procedure, the hybridization of four organic building blocks including liposomes, micelles, dendrimers, and polymeric nanocapsules with five functional inorganic nanoparticles comprising gold nanostructures, magnetic nanoparticles, carbon-based materials, quantum dots, and silica nanoparticles will be highlighted. The recent progress of these O/I hybrids in advanced modalities for combating cancer, such as, therapeutic agent delivery, photothermal therapy, photodynamic therapy, and immunotherapy will be systematically reviewed.

Application of Gold Nanoparticle-Based Materials in Cancer Therapy and Diagnostics

Several metal nanoparticles have been developed for medical application. While all have their benefits, gold nanoparticles (AuNPs) are ideal in cancer therapy and diagnosis as they are chemically inert and minimally toxic. Several studies have shown the potential of AuNPs in the therapeutic field, as photosensitizing agents in sonochemical and photothermal therapy and as drug delivery, as well as in diagnostics and theranostics. Although there is a significant number of reviews on the application of AuNPs in cancer medicine, there is no comprehensive review on their application both in therapy and diagnostics. Therefore, considering the high number of studies on AuNPs’ applications, this review summarizes data on the application of AuNPs in cancer therapy and diagnostics. In addition, we looked at the influence of AuNPs’ shape and size on their biological properties. We also present the potential use of hybrid materials based on AuNPs in sonochemical and photothermal therapy and the possibility of their use in diagnostics. Despite their potential, the use of AuNPs and derivatives in cancer medicine still has some limitations. In this review, we provide an overview of the biological, physicochemical, and legal constraints on using AuNPs in cancer medicine.

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

Silver nanoparticles functionalized Paclitaxel nanocrystals enhance overall anti-cancer effect on human cancer cells

For chemotherapeutic drugs, precise tumor-targeting and high anti-cancer efficiency is equally important in order to enhance chemotherapy and reverse drug resistance. The combination of multifunctional agents to achieve synergy should be a promising strategy. In our study, we have successfully developed novel multifunctionalized drug nanocrystals to realize co-delivery of the organic drug Paclitaxel (PTX), inorganic silver nanoparticles (AgNPs) and a tumor targeting agent. To be specific, PTX nanocrystals were first prepared as a template, then coated with polydopamine (PDA). The PDA layer was utilized as the connection bridge to produce and deposit AgNPs in situ, and provide sites for tumor-targeting peptide NR1 (RGDARF) grafting. As a result, these NR1/AgNP-decorated drug nanocrystals exhibited dramatically improved cellular uptake efficiency, in vitro anti-cancer activity and an anti-migratory effect against a variety of cancer cells, which was attributable to the synergistic, or at least additive, effect of the AgNPs and PTX, enhanced cellular uptake efficiency through NR1-receptor interaction, pH-responsive drug release and the nanoscaled nature. In particular, high anti-cancer activity and low side effects from these NR1/AgNP-decorated PTX nanocrystals were well balanced in terms of good selectivity and biocompatibility. Moreover, these novel drug nanocrystals displayed strong apoptotic-inducing potency, resulting in cell membrane lysis, nuclear damage, mitochondria dysfunction, excessive ROS release and double-stranded DNA breakage. The potential acting mechanism and molecular basis of these novel drug nanocrystals is relevant to the regulation of mitochondria-mediated apoptosis with a greater Bax-to-Bcl-2 ratio and the activation of pro-apoptotic P53 and caspase 3.

A photoluminescent folic acid-derived carbon dot functionalized magnetic dendrimer as a pH-responsive carrier for targeted doxorubicin delivery

A fluorescent folic acid carbon dot-grafted magnetic dendrimer was synthesized as a potential carrier for targeted delivery of DOX drug in an acidic medium (pH 5). The carrier showed biodegradability, high colloidal stability, and good biocompatibility towards A549 cells.

99mTc-Methionine Gold Nanoparticles as a Promising Biomaterial for Enhanced Tumor Imaging

Methionine-gold nanoparticles (MGNs) was synthesized by conjugating methionine via dithiocarbamate linkage to gold nanoparticles (GNPs), prepared simultaneously by one pot modified Burst method. Formation of MGNs was confirmed by UV-visible spectroscopy and appearance of new IR bands in the range of 934 cm^-1 to 1086 cm^-1 and shifting of N-C,S-S and S-C-S stretching, confirms the involvement of '-S-C-S-' group of methionine dithiocarbamate with GNPs. The presence of Au in MGNs was confirmed by EDXA spectrum, whereas TEM, SAED and XRD revealed that MGNs are nanocrystalline (~13 nm) and have face-centered cubic structure. MGNs was labeled with ^99mTc (TMGNs) with radiolabeling efficiency greater than 99% using 300 μg of stannous chloride, pH 7 and 90.6 MBq of ^99mTcO₄. The stability data showed that the conjugate will remain infrangible in systemic circulation and in acidic microenvironment of tumor. The blood kinetic profile of TMGN in rabbits and biodistribution studies in EAT tumor bearing balb/c mice showed longer in vivo circulation and slow clearance compared to radiolabeled methionine (TM). TMGN demonstrated nearly three-fold higher tumor accumulation (3.9 ± 0.35% ID/g), 2-fold lower tumor saturation dose (1.0 μg/kg) and higher tumor retention compared with TM. Data showed that the TMGN tumor: blood ratio (1.05) is nearly 2.5-fold higher than TM (0.44), whereas TMGN tumor: muscle ratio (97.5) is nearly 8-fold higher than TM (11.6). In conclusion, TMGN showed excellent tumor targeting and has promising prospects as a SPECT-radiopharmaceutical for imaging tumors.

Nanocarrier anticancer drug-conjugates cause higher cellular deformations: culpable for mischief

Here we report nanocarrier-anticancer drug conjugates culpable for cellular deformations, critically evidenced through image-based analysis as a measure of karyoplasmic ratio (KR) and nuclear surface area (NSA). Multiwalled carbon nanotubes (MWCNTs) were coordinated additionally with Fe3O4 nanoparticles (NPs) to evaluate the symbiotic influence, and further conjugated to Dox for evaluating the cellular kinetics and for measuring cell deformations. Cellular entry kinetics of the CNT (CNT-Dox and CNT-Cys-Fe3O4-Dox) nanocarriers and their efficiency in nuclear localization were evaluated using cervical cancer (HeLa) cells. Of note, the Dox-bound nanocarriers showed significantly enhanced cell toxicity over the free form of the drug. CNT-Dox and CNT-Cys-Fe3O4-Dox influx occurred within 4 hours, while maximum cellular retention of Dox was observed for CNT-Dox at 24 h. However, the highest KR (∼0.51) was observed for CNT-Dox within 8 hours indicating similar cellular deformations using nanocarrier anticancer drug-conjugates to that of free Dox (KR ∼0.50) at 4 hours. In addition, we observed increased NSA at 4 h in Dox treatment whereas in the case of the Dox conjugated nanocarrier, increased NSA was noted at 8 h treatment. At 8 h exposure of HeLa cells with Dox conjugates, we observed that the cells fall into distinct regions of the morphospace with respect to KR and NSA. Conclusively, nano delivery systems considered for clinical and biomedical translations must take into account the possible negative influences imparting higher cellular deformations and secondary adverse effects over the free form of the drug.

Multi-transformable nanocarrier with tumor extracellular acidity-activated charge reversal, size reduction and ligand reemergence for in vitro efficient doxorubicin loading and delivery

Various nanoparticles as drug delivery system provide significant improvements in the cancer treatment. However, their clinical success remains elusive in large part due to their inability to overcome both systemic and tumor tissue barriers. The nanosystems with nanoproperty-transformability (surface, size, stability and target) hold great promise for achieving enhanced delivery efficacy. However, currently available systems that are mainly polymer-based assemblies usually suffer from the intrinsic drawbacks of poor stability, premature leakage and low drug loading as well as limited transformability. In this study, we designed a facile strategy to build a novel multi-transformable MSNs@GO nanosystem for efficient doxorubicin (DOX) loading and delivery. This novel nanosystem was well characterized and investigated in vitro. The results indicated that the MSNs@GO can realize a very high drug loading ability due to the large pore surface area of MSNs and the demonstrated donor-acceptor (boron‑nitrogen) coordination interactions between phenylboronic acid-containing nanocarriers and electron donor-containing DOX. More importantly, the novel nanocarriers can simultaneously achieve charge reversal, size reduction and ligand reemergence by shielding/deshielding transition via acid-cleavable dynamic boronate bonds under in vitro simulated acidic microenvironment of tumor tissues, opening a new avenue for improving delivery efficiency of chemotherapeutics.

Hyaluronic Acid-Coated Camptothecin Nanocrystals for Targeted Drug Delivery to Enhance Anticancer Efficacy

Tumor-targeted drug delivery via chemotherapy is very effective on cancer treatment. For potential anticancer agent such as Camptothecin (CPT), high chemotherapeutic efficacy and accurate tumor targeting are equally crucial. Inspired by special CD44 binding capability from hyaluronic acid (HA), in this study, novel HA-coated CPT nanocrystals were successfully prepared by an antisolvent precipitation method for tumor-targeted delivery of hydrophobic drug CPT. These HA-coated CPT nanocrystals demonstrated high drug loading efficiency, improved aqueous dispersion, prolonged circulation, and enhanced stability resulting from their nanoscaled sizes and hydrophilic HA layer. Moreover, as compared to crude CPT and naked CPT nanocrystals, HA-coated CPT nanocrystals displayed dramatically enhanced in vitro anticancer activity, apoptosis-inducing potency against CD44 overexpressed cancer cells, and lower toxic effect toward normal cells due to pH-responsive drug release behavior and specific HA-CD44 mediated endocytosis. Additionally, HA-coated CPT nanocrystals performed fairly better antimigration activity and biocompatibility. The possible molecular mechanism regarding this novel drug formulation might be linked to intrinsic mitochondria-mediated apoptosis by an increase of Bax to Bcl-2 ratio and upregulation of P53. Consequently, HA-coated CPT nanocrystals are expected to be an effective nanoplatform in drug delivery for cancer therapy.

Review on marine carbohydrate-based gold nanoparticles represented by alginate and chitosan for biomedical application

Gold nanoparticles (AuNPs) have been attracted considerable attention in cancer therapy, drug delivery and other applications due to their unique physical, chemical, and optical properties. Marine carbohydrates are important biological macromolecules that widely exist in marine algae and animals, such as alginate, carrageenan, porphyran, fucoidan, ulvan, agarose, and chitosan. Their excellent properties, such as biocompatibility, biodegradability and no irritation, make them widely used in biomedicine and nanomaterials fields. More importantly, they can be easily modified by functional groups, such as sulfation, acetylation, and carboxylation, to further extend their applications. The marine carbohydrates functionalized AuNPs can increase their biocompatibility and targeting in a green preparation method. Here, we review recent advances on marine carbohydrate-based AuNPs for cancer therapy, imaging, drug delivery and other biomedical fields. The topics of selective surface modification in different carbohydrates and further biomedical applications of AuNPs are also discussed.

Gold Nanocomplex Strongly Modulates the PI3K/Akt Pathway and Other Pathways in MCF-7 Breast Cancer Cell Line

Conjugating drugs with gold nanoparticles (GNP) is a key strategy in cancer therapy. Herein, the potential inhibition of the phosphatidylinositol 3-kinase (PI3K)/Akt pathway, and other pathways of the MCF-7 cell-line, was investigated upon treatment with gold nanorods (GNR) conjugated with a PI3K inhibitor drug. The results revealed that the coupling of GNR with the drug drastically modulated the expression of PI3Kα at the gene and protein levels compared to the drug or GNR alone. The PI3Kα pathway is involved in tumor progression and development through the mediation of different mechanisms such as apoptosis, proliferation, and DNA damage. Treatment with the nanocomplex significantly affected the gene expression of several transcription factors responsible for cell growth and proliferation, apoptotic pathways, and cell cycle arrest. Furthermore, the gene expression of different regulatory proteins involved in cancer progression and immune responses were significantly modified upon treatment with the nanocomplex compared to the free drug or GNR alone.

Acid-labile anhydride-linked doxorubicin-doxorubicin dimer nanoparticles as drug self-delivery system with minimized premature drug leakage and enhanced anti-tumor efficacy

Acid-labile anhydride-linked doxorubicin-doxorubicin dimers (D-DOX) were designed as doxorubicin-doxorubicin conjugate-based drug self-delivery systems (DSDSs) with high drug content for tumor intracellular pH-triggered release, by conjugating doxorubicin (DOX) with various anhydrides, such as maleic anhydride (MAH), succinic anhydride (suc), and 2,3-dimethylmaleic anhydride (DMMAH). With the similar diameter of about 200 nm, the D-DOXMAH showed better pH-triggered DOX release and was thus selected for the further investigation. The D-DOX-5 nanoparticles with desirable average hydrodynamic diameter (Dh) of 162 nm and high drug content of 51.20% were obtained via self-assembly by a facile dialysis technique, with the PEGylated dimer (D-DOXMAH-S-PEG) as surfactant. The cumulative DOX release from the proposed D-DOX nanoparticles reached 40.6% within 36 h in the simulated tumor intracellular acidic micro-environment, while the premature drug leakage was only 4.5% in the simulated normal physiological medium. The MTT results indicated the proposed DSDS possessed an enhanced anti-tumor efficacy for the HepG2 cancer cell than the free DOX.

Cell deformation and acquired drug resistance: elucidating the major influence of drug-nanocarrier delivery systems

Cancer diagnosis and its stage-wise assessment are determined through invasive solid tissue biopsies. Conversely, cancer imaging is enriched through emission tomography and longitudinal high-resolution analysis for the early detection of cancer through altered cell morphology and cell-deformation. Similarly, in post multiple chemo-cycle exposures, the tumor regression and progression thereafter are not well understood. Here, we report chemo-cycles of doxorubicin (Dox) carrying nanoparticles (NPs) to be highly indicative of cell deformation and a progressive indicator of phenotypic expressions of acquired drug resistance (ADR). We designed graphene (G) based nanocarriers by chemically conjugating multiple components: (i) G; (ii) iron oxide (Fe3O4) NPs; and (iii) Dox through a cysteine (Cys) linker (G-Dox and G-Cys-Fe3O4-Dox). Although Dox underwent cell diffusion, the G-based nanocarriers followed a receptor-mediated endocytosis which created a profound impact on the cell membrane integrity. ADR owing to Dox and G-based nanocarriers was analyzed through a cytotoxicity assay, cell morphology deformation parameters and cellular uptake kinetic patterns. Interestingly, after the third chemo-cycle, G-Dox incubated cells showed the greatest decrease in the alteration of the nuclear surface area (NSA) of ∼28%, a ∼40% reduction of the cell surface area (CSA) and a ∼32% increase in the cell roundness (CRd). Our results suggested that the G-based nanocarriers induced the cell deformation process, subsequently resulting in ADR. Although the G-based nanocarriers initiated ADR, G-Dox was most cytotoxic to cancer cells and induced the maximum cell morphology deformation within our scope of study. This outcome implies caution is needed when using G-based nanocarriers and other multi-component nanosystems for Dox delivery as they lead to possible phenotypic expressions of drug resistance in cancer cells.

Lytic peptide-grafted beta-cyclodextrin polymer based nano-scaled drug delivery system with enhanced camptothecin anti-cancer efficacy

The aqueous solubility of drug molecules is closely related to its bioactivity like bioavailability and subsequent therapeutic index, especially in the case of hydrophobic drugs like camptothecin (CPT), a potential broad-spectrum anti-cancer agent. Enhanced anti-cancer activity and selectivity of CPT are equally important. Inspired by host-guest effect and drug combination regimen, we developed a novel tumor lytic peptide incorporated drug delivery system by forming beta-cyclodextrin polymer (BCDp) based inclusion complex in nano-scaled size. In this study, BCDp formed inclusion complex with CPT and then a lytic-type peptide (ZH) was grafted. The resulting combinational formulation of BCDp, CPT and ZH, named as ZH-BCDp-CPT inclusion complex, demonstrated greater solubility resulting from its nano-scaled size, amorphous solid state and inclusion structure. Moreover, ZH facilitated quick internalization of conjugated drug via cell membrane lysis, leading to efficient intracellular drug delivery. This novel drug formulation was featured with prolonged circulation, enhanced anti-cancer efficacy, selectivity, anti-cell migration activity and better biocompatibility in comparison with crude CPT and binary BCDp-CPT inclusion complex, all of which were attributed to a cooperative action between ZH and BCDp-CPT inclusion complex. Our results suggested ZH-BCDp-CPT inclusion complex induced cell apoptosis by up-regulation of Bax and P53 and down-regulation of Bcl-2, primarily involved in the mitochondrial pathways.

In Vitro Drug Release and Biocatalysis from pH-Responsive Gold Nanoparticles Synthesized Using Doxycycline

pH-sensitive doxycycline gold nanoparticles (doxy-AuNPs) are reported here to act as effective drug nanocarriers and as biocatalysts. The AuNPs were synthesized with doxy as the reducing and capping agent. Various parameters were optimized to find the best conditions for the synthesis of doxy-AuNPs, and these were characterized with UV-vis, X-ray diffraction (XRD), FTIR, and transmission electron microscopy (TEM). Doxy-AuNPs were then loaded with the anticancer drug doxorubicin (DOX), where 70% of the initially available drug was loaded within 24 h. Furthermore, pH-dependent drug release was measured at 60% with in vitro measurements in phosphate-buffered saline (PBS). In addition, the doxy-AuNPs were applied as a biocatalyst. Oxidation of dopamine was taken as a model reaction to determine the catalytic activity of doxy-AuNPs. Almost complete oxidation of dopamine occurred in 5 min, which indicates the fast response of synthesized doxy-AuNPs as a biocatalyst. Hence, doxy-AuNPs are a versatile platform for drug loading and biocatalyst.

Utilization of green formulation technique and efficacy estimation on cell line studies for dual anticancer drug therapy with niosomes

The aim of the present study was to prepare niosome formulations for the simultaneous encapsulation, dual drug therapy, of two anticancer drugs by the ecological probe sonication method. Poloxamer and sorbitan monostearate were used as surface active agents in niosomes, and the water soluble doxorubicin and poorly-water soluble paclitaxel were used as anticancer drugs. Thorough physicochemical analysis were performed for the niosomes, and their cytotoxicity and activity were evaluated on MCF-7 and PC3-MM2 cancer cell lines. Prepared niosomes were small in size with sizes ranging from 137 nm to 893 nm, and entrapment efficiencies were high, ranging from 91.24% to 99.99%. During the four weeks stability testing, the particle size remained stable. The niosomal formulations showed in vitro sustained drug release profiles for doxorubicin and clearly increased the dissolution rate of poorly water soluble paclitaxel. The incorporation of both the drugs into niosomes improved cell penetration and antiproliferative activity of the drugs PC3-MM2 cell lines. As a conclusion, doxorubicin and paclitaxel loaded niosome formulations resulted in relatively stable, small sized niosomes with improved drug release profiles, low toxicity, better cell penetration and antiproliferative activity. The niosomes showed synergistic effect due to the presence of both drugs, which can overcome multidrug resistance.

Insights into the Cellular Uptake, Cytotoxicity, and Cellular Death Modality of Phospholipid-Coated Gold Nanorods toward Breast Cancer Cell Lines

Gold nanorods (GNRs) have gained pronounced recognition in the diagnosis and treatment of cancers driven by their distinctive properties. Herein, a gold-based nanosystem was prepared by utilizing a phospholipid moiety linked to thiolated polyethylene glycol, 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-PEG-SH, as a surface decorating agent. The synthesized phospholipid-PEG-GNRs displayed good colloidal stability upon exposure to the tissue culture medium. Cytotoxicity of phospholipid-PEG-GNRs was investigated toward MCF-7 and T47D breast cancer cells using sulforhodamine B test. The results revealed that phospholipid-PEG-GNRs demonstrated  high cytotoxicity to MCF-7 cells compared to T47D cells, and minimal cytotoxicity to human dermal fibroblasts. The cellular uptake studies performed by imaging and quantitative analysis demonstrated  massive internalization of phospholipid-coated GNRs into  MCF-7 cells in comparison to T47D cells. The cellular death modality of cancer cells after treatment with phospholipid-PEG-GNRs was evaluated using mitochondrial membrane potential assay (JC-1 dye), gene expression analysis, and flow cytometry study. The overall results suggest that phospholipid-modified GNRs enhanced mainly the cellular apoptotic events in MCF-7 cells in addition to necrosis, whereas cellular necrosis and suppression of cellular invasion contributed to the cellular death modality in the T47D cell line upon treatment with phospholipid-PEG-GNRs. The phospholipid-coated GNRs interact in a different manner with breast cancer cell lines and could be considered for breast cancer treatment.

Ruthenium dendrimers against acute promyelocytic leukemia: in vitro studies on HL-60 cells

Coordination of ruthenium arene fragments on carbosilane dendrimers' surface greatly increases their antitumor properties. Newly synthetized ruthenium dendrimers are water-soluble, monodisperse and stable. Since carbosilane dendrimers are good carriers of drugs and genes, the presence of ruthenium in their structure makes them promising candidates for new drug delivery systems with improved antitumor potential. Carbosilane ruthenium dendrimers are more toxic to cancer cells than normal cells. Results of several in vitro studies applied here indicate that carbosilane ruthenium dendrimers induce apoptosis in promyelocytic leukemia HL-60 cells.

Epirubicin-loaded marine carrageenan oligosaccharide capped gold nanoparticle system for pH-triggered anticancer drug release

Gold nanoparticles (AuNPs) and the pH stimuli-responsive drug delivery system have been extensively applied in cancer treatment. Carrageenan derived from marine red algae shows a promising application prospect for drug delivery as a nanomaterial for its biodegradability, abundance, and non-toxicity. Carrageenan oligosaccharide (CAO) was used as a biocompatible reductant for green synthesis of CAO-AuNPs, and the obtained CAO-AuNPs were further used as a delivery system for pH-triggered delivery of epirubicin (EPI). The EPI-CAO-AuNPs were demonstrated to be spherical and homogeneous with mean diameter of 141 ± 6 nm by means of electron microscopy and Malvern particle size analyzer. Results showed that the release of EPI from EPI-CAO-AuNPs was significant under acidic condition that simulated cancer environment, while it was negligible under physiological pH in vitro. Confocal laser scanning microscope and flow cytometry analysis showed that EPI-CAO-AuNPs were localized in cellular nucleus and induced more apoptosis of HCT-116 and HepG2 cells than free EPI. A new pH-triggered anticancer drug release was achieved by EPI-CAO-AuNPs system for the first time. The developed EPI-CAO-AuNPs nanosystem shows a promising prospect for pH-triggered delivery of antitumor drugs, and our work provides a new idea for targeted drug delivery by using biocompatible marine carbohydrates as nanomaterial.