Using Gold Nanoparticles To Disrupt the Tumor Microenvironment: An Emerging Therapeutic Strategy

Antibody and siRNA Nanocarriers to Suppress Wnt Signaling, Tumor Growth, and Lung Metastasis in Triple-Negative Breast Cancer

The paucity of targeted therapies for triple-negative breast cancer (TNBC) causes patients with this aggressive disease to suffer a poor clinical prognosis. A promising target for therapeutic intervention is the Wnt signaling pathway, which is activated in TNBC cells when extracellular Wnt ligands bind overexpressed Frizzled7 (FZD7) transmembrane receptors. This stabilizes intracellular β-catenin proteins that in turn promote transcription of oncogenes that drive tumor growth and metastasis. To suppress Wnt signaling in TNBC cells, we developed therapeutic nanoparticles (NPs) functionalized with FZD7 antibodies and β-catenin small interfering RNAs (siRNAs). The antibodies enable TNBC cell-specific binding and inhibit Wnt signaling by locking FZD7 receptors in a ligand unresponsive state, while the siRNAs suppress β-catenin through RNA interference. Compared to NPs coated with antibodies or siRNAs individually, NPs coated with both agents more potently reduce the expression of several Wnt related genes in TNBC cells, leading to greater inhibition of cell proliferation, migration, and spheroid formation. In two murine models of metastatic TNBC, the dual antibody/siRNA nanocarriers outperformed controls in terms of inhibiting tumor growth, metastasis, and recurrence. These findings demonstrate suppressing Wnt signaling at both the receptor and mRNA levels via antibody/siRNA nanocarriers is a promising approach to combat TNBC.

Bioresponsive nanocomplex integrating cancer-associated fibroblast deactivation and immunogenic chemotherapy for rebuilding immune-excluded tumors

Cancer-associated fibroblasts (CAFs) play a crucial role in creating an immunosuppressive environment and remodeling the extracellular matrix within tumors, leading to chemotherapy resistance and limited immune cell infiltration. To address these challenges, integrating CAFs deactivation into immunogenic chemotherapy may represent a promising approach to the reversal of immune-excluded tumor. We developed a tumor-targeted nanomedicine called the glutathione-responsive nanocomplex (GNC). The GNC co-loaded dasatinib, a CAF inhibitor, and paclitaxel, a chemotherapeutic agent, to deactivate CAFs and enhance the effects of immunogenic chemotherapy. Due to the modification with hyaluronic acid, the GNC preferentially accumulated in the tumor periphery and responsively released cargos, mitigating the tumor stroma as well as overcoming chemoresistance. Moreover, GNC treatment exhibited remarkable immunostimulatory efficacy, including CD8+ T cell expansion and PD-L1 downregulation, facilitating immune checkpoint blockade therapy. In summary, the integration of CAF deactivation and immunogenic chemotherapy using the GNC nanoplatform holds promise for rebuilding immune-excluded tumors.

Nanoparticles in tumor microenvironment remodeling and cancer immunotherapy

Cancer immunotherapy and vaccine development have significantly improved the fight against cancers. Despite these advancements, challenges remain, particularly in the clinical delivery of immunomodulatory compounds. The tumor microenvironment (TME), comprising macrophages, fibroblasts, and immune cells, plays a crucial role in immune response modulation. Nanoparticles, engineered to reshape the TME, have shown promising results in enhancing immunotherapy by facilitating targeted delivery and immune modulation. These nanoparticles can suppress fibroblast activation, promote M1 macrophage polarization, aid dendritic cell maturation, and encourage T cell infiltration. Biomimetic nanoparticles further enhance immunotherapy by increasing the internalization of immunomodulatory agents in immune cells such as dendritic cells. Moreover, exosomes, whether naturally secreted by cells in the body or bioengineered, have been explored to regulate the TME and immune-related cells to affect cancer immunotherapy. Stimuli-responsive nanocarriers, activated by pH, redox, and light conditions, exhibit the potential to accelerate immunotherapy. The co-application of nanoparticles with immune checkpoint inhibitors is an emerging strategy to boost anti-tumor immunity. With their ability to induce long-term immunity, nanoarchitectures are promising structures in vaccine development. This review underscores the critical role of nanoparticles in overcoming current challenges and driving the advancement of cancer immunotherapy and TME modification.

Microneedle-mediated delivery of Ziconotide-loaded liposomes fused with exosomes for analgesia

Ziconotide (ZIC) is an N-type calcium channel antagonist for treating severe chronic pain that is intolerable, or responds poorly to the administration of other drugs, such as intrathecal morphine and systemic analgesics. As it can only work in the brain and cerebrospinal fluid, intrathecal injection is the only administration route for ZIC. In this study, borneol (BOR)-modified liposomes (LIPs) were fused with exosomes from mesenchymal stem cells (MSCs) and loaded with ZIC to prepare microneedles (MNs) to improve the efficiency of ZIC across the blood-brain barrier. To evaluate local analgesic effects of MNs, the sensitivity of behavioral pain to thermal and mechanical stimuli was tested in animal models of peripheral nerve injury, diabetes-induced neuropathy pain, chemotherapy-induced pain, and ultraviolet-B (UV-B) radiation-induced neurogenic inflammatory pain. BOR-modified LIPs loaded with ZIC were spherical or nearly spherical, with a particle size of about 95 nm and a Zeta potential of -7.8 mV. After fusion with MSC exosomes, the particle sizes of LIPs increased to 175 nm, and their Zeta potential increased to -3.8 mV. The nano-MNs constructed based on BOR-modified LIPs had good mechanical properties and could effectively penetrate the skin to release drugs. The results of analgesic experiments showed that ZIC had a significant analgesic effect in different pain models. In conclusion, the BOR-modified LIP membrane-fused exosome MNs constructed in this study for delivering ZIC provide a safe and effective administration for chronic pain treatment, as well as great potential for clinical application of ZIC.

NFL-TBS.40-63 Peptide Gold Complex Nanovector: A Novel Therapeutic Approach to Increase Anticancer Activity by Breakdown of Microtubules in Pancreatic Adenocarcinoma (PDAC)

The role of the NFL-TBS.40-63 peptide is to destroy the microtubule network of target glioma cancer cells. Recently, we have conceived a gold-complex biotinylated NFL-TBS.40-63 (BIOT-NFL) to form a hybrid gold nanovector (BIOT-NFL-PEG-AuNPs). This methodology showed, for the first time, the ability of the BIOT-NFL-PEG-AuNPs to target the destruction of pancreatic cancer cells (PDAC) under experimental conditions, as well as detoxification and preclinical therapeutic efficacy regulated by the steric and chemical configuration of the peptide. For this aim, a mouse transplantation tumor model induced by MIA-PACA-2 cells was applied to estimate the therapeutic efficacy of BIOT-NFL-PEG-AuNPs as a nanoformulation. Our relevant results display that BIOT-NFL-PEG-AuNPs slowed the tumor growth and decreased the tumor index without effects on the body weight of mice with an excellent antiangiogenic effect, mediated by the ability of BIOT-NFL-PEG-AuNPs to alter the metabolic profiles of these MIA-PACA-2 cells. The cytokine levels were detected to evaluate the behavior of serum inflammatory factors and the power of BIOT-NFL-PEG-AuNPs to boost the immune system.

Nanomaterial-Based Drug Delivery Systems: A New Weapon for Cancer Immunotherapy

Cancer immunotherapy, a major breakthrough in cancer treatment, has been successfully applied to treat a number of tumors. However, given the presence of factors in the tumor microenvironment (TME) that impede immunotherapy, only a small proportion of patients achieve a good clinical response. With the ability to increase permeability and cross biological barriers, nanomaterials have been successfully applied to deliver immunotherapeutic agents, thus realizing the anti-cancer therapeutic potential of therapeutic agents. This has driven a wave of research into systems for the delivery of immunotherapeutic agents, which has resulted in widespread interest in nanomaterial-based drug delivery systems. Nanomaterial-based drug delivery systems are able to overcome the challenges from TME and thus achieve good results in cancer immunotherapy. If it can make a breakthrough in improving biocompatibility and reducing cytotoxicity, it will be more widely used in clinical practice. Different types of nanomaterials may also have some subtle differences in enhancing cancer immunotherapy. Moreover, delivery systems made of nanomaterials loaded with drugs, such as cytotoxic drugs, cytokines, and adjuvants, could be used for cancer immunotherapy because they avoid the toxicity and side effects associated with these drugs, thereby enabling their reuse. Therefore, further insights into nanomaterial-based drug delivery systems will provide more effective treatment options for cancer patients.

Cancer-associated fibroblasts: Origin, function, imaging, and therapeutic targeting

The tumor microenvironment (TME) is emerging as one of the primary barriers in cancer therapy. Cancer-associated fibroblasts (CAF) are a common inhabitant of the TME in several tumor types and play a critical role in tumor progression and drug resistance via different mechanisms such as desmoplasia, angiogenesis, immune modulation, and cancer metabolism. Due to their abundance and significance in pro-tumorigenic mechanisms, CAF are gaining attention as a diagnostic target as well as to improve the efficacy of cancer therapy by their modulation. In this review, we highlight existing imaging techniques that are used for the visualization of CAF and CAF-induced fibrosis and provide an overview of compounds that are known to modulate CAF activity. Subsequently, we also discuss CAF-targeted and CAF-modulating nanocarriers. Finally, our review addresses ongoing challenges and provides a glimpse into the prospects that can spearhead the transition of CAF-targeted therapies from opportunity to reality.

Nanomedicine Penetration to Tumor: Challenges, and Advanced Strategies to Tackle This Issue

Nanomedicine has been under investigation for several years to improve the efficiency of chemotherapeutics, having minimal pharmacological effects clinically. Ineffective tumor penetration is mediated by tumor environments, including limited vascular system, rising cancer cells, higher interstitial pressure, and extra-cellular matrix, among other things. Thus far, numerous methods to increase nanomedicine access to tumors have been described, including the manipulation of tumor micro-environments and the improvement of nanomedicine characteristics; however, such outdated approaches still have shortcomings. Multi-functional convertible nanocarriers have recently been developed as an innovative nanomedicine generation with excellent tumor infiltration abilities, such as tumor-penetrating peptide-mediated transcellular transport. The developments and limitations of nanomedicines, as well as expectations for better outcomes of tumor penetration, are discussed in this review.

Disabling partners in crime: Gold nanoparticles disrupt multicellular communications within the tumor microenvironment to inhibit ovarian tumor aggressiveness

The tumor microenvironment (TME) plays a key role in the poor prognosis of many cancers. However, there is a knowledge gap concerning how multicellular communication among the critical players within the TME contributes to such poor outcomes. Using epithelial ovarian cancer (EOC) as a model, we show how crosstalk among cancer cells (CC), cancer associated fibroblasts (CAF), and endothelial cells (EC) promotes EOC growth. We demonstrate here that co-culturing CC with CAF and EC promotes CC proliferation, migration, and invasion in vitro and that co-implantation of the three cell types facilitates tumor growth in vivo. We further demonstrate that disruption of this multicellular crosstalk using a gold nanoparticle (GNP) inhibits these pro-tumorigenic phenotypes in vitro as well as tumor growth in vivo. Mechanistically, GNP treatment reduces expression of several tumor-promoting cytokines and growth factors, resulting in inhibition of MAPK and PI3K-AKT activation and epithelial-mesenchymal transition - three key oncogenic signaling pathways responsible for the aggressiveness of EOC. The current work highlights the importance of multicellular crosstalk within the TME and its role for the aggressive nature of EOC, and demonstrates the disruption of these multicellular communications by self-therapeutic GNP, thus providing new avenues to interrogate the crosstalk and identify key perpetrators responsible for poor prognosis of this intractable malignancy.

Acute exposure to gold nanoparticles aggravates lipopolysaccharide-induced liver injury by amplifying apoptosis via ROS-mediated macrophage-hepatocyte crosstalk

Background

Gold nanoparticles (AuNPs) are increasingly utilized in industrial and biomedical fields, thereby demanding a more comprehensive knowledge about their safety. Current toxicological studies mainly focus on the unfavorable biological impact governed by the physicochemical properties of AuNPs, yet the consequences of their interplay with other bioactive compounds in biological systems are poorly understood.

Results

In this study, AuNPs with a size of 10 nm, the most favorable size for interaction with host cells, were given alone or in combination with bacterial lipopolysaccharide (LPS) in mice or cultured hepatic cells. The results demonstrated that co exposure to AuNPs and LPS exacerbated fatal acute liver injury (ALI) in mice, although AuNPs are apparently non-toxic when administered alone. AuNPs do not enhance systemic or hepatic inflammation but synergize with LPS to upregulate hepatic apoptosis by augmenting macrophage-hepatocyte crosstalk. Mechanistically, AuNPs and LPS coordinate to upregulate NADPH oxidase 2 (NOX2)-dependent reactive oxygen species (ROS) generation and activate the intrinsic apoptotic pathway in hepatic macrophages. Extracellular ROS generation from macrophages is then augmented, thereby inducing calcium-dependent ROS generation and promoting apoptosis in hepatocytes. Furthermore, AuNPs and LPS upregulate scavenger receptor A expression in macrophages and thus increase AuNP uptake to mediate further apoptosis induction.

Conclusions

This study reveals a profound impact of AuNPs in aggravating the hepatotoxic effect of LPS by amplifying ROS-dependent crosstalk in hepatic macrophages and hepatocytes.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s12951-021-01203-w.

Nanoplatforms for Sepsis Management: Rapid Detection/Warning, Pathogen Elimination and Restoring Immune Homeostasis

Sepsis, a highly life-threatening organ dysfunction caused by uncontrollable immune responses to infection, is a leading contributor to mortality in intensive care units. Sepsis-related deaths have been reported to account for 19.7% of all global deaths. However, no effective and specific therapeutic for clinical sepsis management is available due to the complex pathogenesis. Concurrently eliminating infections and restoring immune homeostasis are regarded as the core strategies to manage sepsis. Sophisticated nanoplatforms guided by supramolecular and medicinal chemistry, targeting infection and/or imbalanced immune responses, have emerged as potent tools to combat sepsis by supporting more accurate diagnosis and precision treatment. Nanoplatforms can overcome the barriers faced by clinical strategies, including delayed diagnosis, drug resistance and incapacity to manage immune disorders. Here, we present a comprehensive review highlighting the pathogenetic characteristics of sepsis and future therapeutic concepts, summarizing the progress of these well-designed nanoplatforms in sepsis management and discussing the ongoing challenges and perspectives regarding future potential therapies. Based on these state-of-the-art studies, this review will advance multidisciplinary collaboration and drive clinical translation to remedy sepsis.

Recent advances in nanoparticles mediated photothermal therapy induced tumor regression

Photothermal therapy (PTT) is a minimally invasive procedure for treating cancer. The two significant prerequisites of PTT are the photothermal therapeutic agent (PTA) and near-infrared radiation (NIR). The PTA absorbs NIR, causing hyperthermia in the malignant cells. This increased temperature at the tumor microenvironment finally results in tumor cell damage. Nanoparticles play a crucial role in PTT, aiding in the passive and active targeting of the PTA to the tumor microenvironment. Through enhanced permeation and retention effect and surface-engineering, specific targeting could be achieved. This novel delivery tool provides the advantages of changing the shape, size, and surface attributes of the carriers containing PTAs, which might facilitate tumor regression significantly. Further, inclusion of surface engineering of nanoparticles is facilitated through ligating ligands specific to overexpressed receptors on the cancer cell surface. Thus, transforming nanoparticles grants the ability to combine different treatment strategies with PTT to enhance cancer treatment. This review emphasizes properties of PTAs, conjugated biomolecules of PTAs, and the combinatorial techniques for a better therapeutic effect of PTT using the nanoparticle platform.

Tailoring therapeutic properties of silver nanoparticles for effective bacterial keratitis treatment

The formulation of nanoparticles with intrinsically therapeutic properties in a tailorable and appropriate manner is critical in nanomedicine for effective treatments of infectious diseases. Here, we present a biomedical strategy to formulate silver nanoparticles (AgNPs) as intrinsically therapeutic agents for the treatment of Staphylococcus aureus (S. aureus) keratitis. Specifically, AgNPs are controllably obtained as spheres, wrapped with a biopolymer, and varied in sizes. in vitro and in vivo studies indicate that biological interactions between the AgNPs and corneal keratocytes, S. aureus bacteria, and blood vessels are strongly determined by the particle sizes. As the size increased from 3.3 ± 0.7 to 37.2 ± 5.3 nm, the AgNPs exhibit better ocular biocompatibility and stronger antiangiogenic activity, but poorer bactericidal performance. In a rabbit model of S. Aureus-induced keratitis, intrastromal injection of AgNP formulations (single dose) show substantial influences of particle size on the treatment efficacy. As the trade-off, AgNPs with medium size of 15.0 ± 3.6 nm reveal as the best therapeutic agent that could offer ∼5.6 and ∼9.1-fold greater corneal thickness recovery respectively compared to those with smaller and larger sizes at 3 days post-administration. These findings suggest an important advance in structural design for formulating intrinsically therapeutic nano-agents toward the efficient management of infectious diseases.

Regulation of tumor microenvironment for pancreatic cancer therapy

Pancreatic cancer (PC) is one kind of the most lethal malignancies worldwide, owing to its insidious symptoms, early metastases, and negative responses to current therapies. With an increasing understanding of pathology, the tumor microenvironment (TME) plays a significant role in ineffective treatment and poor prognosis of PC. Thus, a growing number of studies have focused on whether components of the TME could be effective targets for PC therapy. Biomaterials have been widely applied in cancer therapy, and numerous organic or inorganic biomaterials for TME regulation have been developed to inhibit the growth and metastasis of PC, as well as reverse therapeutic resistance. In this review, we discuss various biomaterials utilized to treat PC based on different components of the TME, including, but not limited to, extracellular matrix (ECM), abnormal tumor vascularization, and tumor-associated immune cells, as well as other unconventional therapeutic strategies. Besides, the perspectives on the underlying future of theranostic nanomedicines for PC therapy are also presented.

Diagnostic and Therapeutic Nanomedicine

Nanotechnology has been widely applied to medical interventions for prevention, diagnostics, and therapeutics of diseases, and the application of nanotechnology for medical purposes, which is called as a term "nanomedicine" has received tremendous attention. In particular, the design and development of nanoparticle for biosensors have received a great deal of attention, since those are most impactful area of clinical translation showing potential breakthrough in early diagnosis of diseases such as cancers and infections. For example, the nanoparticles that have intrinsic unique features such as magnetic responsive characteristics or photoluminescence can be utilized for noninvasive visualization of inner body. Drug delivery that makes use of drug-containing nanoparticles as a carrier is another field of study, in which the particulate form nanomedicine is given by parenteral administration for further systemic targeting to pathological tissues. In addition, encapsulation into nanoparticles gives the opportunity to secure the sensitive therapeutic payloads that are readily degraded or deactivated until reached to the target in biological environments, or to provide sufficient solubilization (e.g., to deliver compounds which have physicochemical properties that strongly limit their aqueous solubility and therefore systemic bioavailability). The nanomedicine is further intended to enhance the targeting index such as increased specificity and reduced false binding, thus improve the diagnostic and therapeutic performances. In this chapter, principles of nanomaterials for medicine will be thoroughly covered with applications for imaging-based diagnostics and therapeutics.

Nanoparticles as Smart Carriers for Enhanced Cancer Immunotherapy

Cancer immunotherapy has emerged as a promising strategy for the treatment of many forms of cancer by stimulating body's own immune system. This therapy not only eradicates tumor cells by inducing strong anti-tumor immune response but also prevent their recurrence. The clinical cancer immunotherapy faces some insurmountable challenges including high immune-mediated toxicity, lack of effective and targeted delivery of cancer antigens to immune cells and off-target side effects. However, nanotechnology offers some solutions to overcome those limitations, and thus can potentiate the efficacy of immunotherapy. This review focuses on the advancement of nanoparticle-mediated delivery of immunostimulating agents for efficient cancer immunotherapy. Here we have outlined the use of the immunostimulatory nanoparticles as a smart carrier for effective delivery of cancer antigens and adjuvants, type of interactions between nanoparticles and the antigen/adjuvant as well as the factors controlling the interaction between nanoparticles and the receptors on antigen presenting cells. Besides, the role of nanoparticles in targeting/activating immune cells and modulating the immunosuppressive tumor microenvironment has also been discussed extensively. Finally, we have summarized some theranostic applications of the immunomodulatory nanomaterials in treating cancers based on the earlier published reports.

Gold Nanoparticles: A New Golden Era in Oncology?

In recent years, the spectrum of possible applications of gold in diagnostics and therapeutic approaches in clinical practice has changed significantly, becoming surprisingly broad. Nowadays, gold-based therapeutic agents are used in the therapy of multiple human diseases, ranging from degenerative to infectious diseases and, in particular, to cancer. At the basis of these performances of gold, there is the development of new gold-based nanoparticles, characterized by a promising risk/benefit ratio that favors their introduction in clinical trials. Gold nanoparticles appear as attractive elements in nanomedicine, a branch of modern clinical medicine, which combines high selectivity in targeting tumor cells and low toxicity. Thanks to these peculiar characteristics, gold nanoparticles appear as the starting point for the development of new gold-based therapeutic strategies in oncology. Here, the new gold-based therapeutic agents developed in recent years are described, with particular emphasis on the possible applications in clinical practice as anticancer agents, with the aim that their application will give rise to a new golden age in oncology and a breakthrough in the fight against cancer.

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

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

Nanoparticles-encapsulated polymeric microneedles for transdermal drug delivery

Polymeric microneedles (MNs) have been leveraged as a novel transdermal drug delivery platform for effective drug permeation, which were widely used in the treatment of various diseases. However, issues including limited loading capacity of hydrophobic drugs, uncontrollable drug release rates, and monotonic therapeutic strategy hamper the further application of polymeric MNs. As a recent emerging research topic, drawing inspiration from the ways that nanomedicine integrated with MNs have opened new avenues for disease therapy. In this review, we examined the recent studies employing nanoparticles (NPs)-encapsulated polymeric MNs (NPs@MNs) for transdermal delivery of various therapeutic cargos, particularly focused on the application of NPs@MNs for diabetes therapy, infectious disease therapy, cancer therapy, and other dermatological disease therapy. We also provided an overview of the clinical potential and future translation of NPs@MNs.

Gold Nanoparticles in Glioma Theranostics

Despite many endeavors to treat malignant gliomas in the last decades, the median survival of patients has not significantly improved. The infiltrative nature of high-grade gliomas and the impermeability of the blood-brain barrier to the most therapeutic agents remain major hurdles, impeding an efficacious treatment. Theranostic platforms bridging diagnosis and therapeutic modalities aim to surmount the current limitations in diagnosis and therapy of glioma. Gold nanoparticles (AuNPs) due to their biocompatibility and tunable optical properties have widely been utilized for an assortment of theranostic purposes. In this Review, applications of AuNPs as imaging probes, drug/gene delivery systems, radiosensitizers, photothermal transducers, and multimodal theranostic agents in malignant gliomas are discussed. This Review also aims to provide a perspective on cancer theranostic applications of AuNPs in future clinical trials.

Triple-Negative Breast Cancer: A Review of Conventional and Advanced Therapeutic Strategies

Triple-negative breast cancer (TNBC) cells are deficient in estrogen, progesterone and ERBB2 receptor expression, presenting a particularly challenging therapeutic target due to their highly invasive nature and relatively low response to therapeutics. There is an absence of specific treatment strategies for this tumor subgroup, and hence TNBC is managed with conventional therapeutics, often leading to systemic relapse. In terms of histology and transcription profile these cancers have similarities to BRCA-1-linked breast cancers, and it is hypothesized that BRCA1 pathway is non-functional in this type of breast cancer. In this review article, we discuss the different receptors expressed by TNBC as well as the diversity of different signaling pathways targeted by TNBC therapeutics, for example, Notch, Hedgehog, Wnt/b-Catenin as well as TGF-beta signaling pathways. Additionally, many epidermal growth factor receptor (EGFR), poly (ADP-ribose) polymerase (PARP) and mammalian target of rapamycin (mTOR) inhibitors effectively inhibit the TNBCs, but they face challenges of either resistance to drugs or relapse. The resistance of TNBC to conventional therapeutic agents has helped in the advancement of advanced TNBC therapeutic approaches including hyperthermia, photodynamic therapy, as well as nanomedicine-based targeted therapeutics of drugs, miRNA, siRNA, and aptamers, which will also be discussed. Artificial intelligence is another tool that is presented to enhance the diagnosis of TNBC.

Salinomycin-Loaded Iron Oxide Nanoparticles for Glioblastoma Therapy

Salinomycin is an antibiotic introduced recently as a new and effective anticancer drug. In this study, magnetic iron oxide nanoparticles (IONPs) were utilized as a drug carrier for salinomycin for potential use in glioblastoma (GBM) chemotherapy. The biocompatible polyethylenimine (PEI)-polyethylene glycol (PEG)-IONPs (PEI-PEG-IONPs) exhibited an efficient uptake in both mouse brain-derived microvessel endothelial (bEnd.3) and human U251 GBM cell lines. The salinomycin (Sali)-loaded PEI-PEG-IONPs (Sali-PEI-PEG-IONPs) released salinomycin over 4 days, with an initial release of 44% ± 3% that increased to 66% ± 5% in acidic pH. The Sali-IONPs inhibited U251 cell proliferation and decreased their viability (by approximately 70% within 48 h), and the nanoparticles were found to be effective in reactive oxygen species-mediated GBM cell death. Gene studies revealed significant activation of caspases in U251 cells upon treatment with Sali-IONPs. Furthermore, the upregulation of tumor suppressors (i.e., p53, Rbl2, Gas5) was observed, while TopII, Ku70, CyclinD1, and Wnt1 were concomitantly downregulated. When examined in an in vitro blood–brain barrier (BBB)-GBM co-culture model, Sali-IONPs had limited penetration (1.0% ± 0.08%) through the bEnd.3 monolayer and resulted in 60% viability of U251 cells. However, hyperosmotic disruption coupled with an applied external magnetic field significantly enhanced the permeability of Sali-IONPs across bEnd.3 monolayers (3.2% ± 0.1%) and reduced the viability of U251 cells to 38%. These findings suggest that Sali-IONPs combined with penetration enhancers, such as hyperosmotic mannitol and external magnetic fields, can potentially provide effective and site-specific magnetic targeting for GBM chemotherapy.

Fibroblasts in the Tumor Microenvironment

The implications of a tumor microenvironment in cancer initiation and progression have drawn interest in recent years. Within the tumor stroma, fibroblasts represent a predominant cell type and are responsible for the majority of extracellular components within the tumor microenvironment, such as matrix and soluble factors. A switch from quiescent fibroblasts to cancer-associated fibroblasts triggers a large variety of pro-tumorigenic signals that support tumor progression and shape the surrounding pathological stroma, with the remodeling of tissue architecture and repression of the local immune response. The heterogeneous nature of cancer-associated fibroblasts and their multiple functions are subject of active research as they could represent promising targets for cutting-edge therapeutic approaches to cancer and the tumor microenvironment.

Multifunctional gold nanoparticles as smart nanovehicles with enhanced tumour-targeting abilities for intracellular pH mapping and in vivo MR/fluorescence imaging

A number of multimodal agents have been developed for tumour imaging and diagnosis, but most of them cannot be used to study the detailed physiological or pathological changes in living cells at the same time. Herein, a series of pH-responsive magnetic resonance and fluorescence imaging (MRI/FI) dual-modal "nanovehicles" are developed and tested. These new dual-modal materials allow for intercellular pH sensing, and those with units that are dually sensitive towards both acidic and basic environments have the ability for intracellular pH mapping and can be used to quantify pH at the cellular level. In addition, detailed pH changes in organelles (including lysosomes and mitochondria) can be investigated at the same time. On the other hand, with the tumour-targeting peptide (cRGD)-modified dual-modal nanovehicles, in vivo tumour MR and fluorescence imaging, which is suitable for cancer diagnosis, can be achieved. Moreover, it has been proved that these materials can pass through the blood brain barrier (BBB). By combining the above mentioned promising properties, these novel multifunctional "nanovehicles" may provide a new method for studying the role of pH during cancer diagnosis and treatment.

Synergistic Radiosensitization by Gold Nanoparticles and the Histone Deacetylase Inhibitor SAHA in 2D and 3D Cancer Cell Cultures

Radiosensitizing agents are capable of augmenting the damage of ionizing radiation preferentially on cancer cells, thereby increasing the potency and the specificity of radiotherapy. Metal-based nanoparticles have recently gathered ground in radio-enhancement applications, owing to their exceptional competence in amplifying the cell-killing effects of irradiation. Our aim was to examine the radiosensitizing performance of gold nanoparticles (AuNPs) and the chromatin-modifying histone deacetylase inhibitor suberoylanilide hydroxamic acid (SAHA) alone and in combination. We observed that the colony-forming capability of cancer cells decreased significantly and the DNA damage, detected by γH2AX immunostaining, was substantially greater after combinational treatments than upon individual drug exposures followed by irradiation. Synergistic radiosensitizing effects of AuNPs and SAHA were proven on various cell lines, including radioresistant A549 and DU-145 cancer cells. 3D cultures often manifest radio- and drug-resistance, nevertheless, AuNPs in combination with SAHA could effectively enhance the potency of irradiation as the number of viable cells decreased significantly when spheroids received AuNP + SAHA prior to radiotherapy. Our results imply that a relaxed chromatin structure induced by SAHA renders the DNA of cancerous cells more susceptible to the damaging effects of irradiation-triggered, AuNP-released reactive electrons. This feature of AuNPs should be exploited in multimodal treatment approaches.

Gold nanoparticles stabilized by PEG-tagged imidazolium salts as recyclable catalysts for the synthesis of propargylamines and the cycloisomerization of γ-alkynoic acids

Water-soluble gold nanoparticles prepared in the presence of PEG-tagged tris-imidazolium bromide, containing Au(0) and Au(i) species, are reusable catalysts.

Advances of functional nanomaterials for cancer immunotherapeutic applications

Immunotherapy has made great progress by modulating the body's own immune system to fight against cancer cells. However, the low response rates of related drugs limit the development of immunotherapy strategies. Fortunately, the advantages of nanotechnology can just make up for this shortcoming. Nanocarriers of diverse systems are utilized to co-deliver antigens and adjuvants, combined with drugs for immunomodulatory, such as chemotherapy, radiotherapy, and photodynamic. Here we review recent studies on immunotherapy with biomimetic, organic, and inorganic nanomaterials. They are going to potentially overcome the drawbacks in cancer immunotherapy with delivering immunomodulatory drugs, delivering cancer vaccine, and monitoring the immune systems. This article is characterized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease.

Cell membrane protein functionalization of nanoparticles as a new tumor-targeting strategy

Nanoparticles have seen considerable popularity as effective tools for drug delivery. However, non-specific targeting continues to remain a challenge. Recently, biomimetic nanoparticles have emerged as an innovative solution that exploits biologically-derived components to improve therapeutic potential. Specifically, cell membrane proteins extracted from various cells (i.e., leukocytes, erythrocytes, platelets, mesenchymal stem cells, cancer) have shown considerable promise in bestowing nanoparticles with increased circulation and targeting efficacy. Traditional nanoparticles can be detected and removed by the immune system which significantly hinders their clinical success. Biomimicry has been proposed as a promising approach to overcome these limitations. In this review, we highlight the current trends in biomimetic nanoparticles and describe how they are being used to increase their chemotherapeutic effect in cancer treatment.

Cell membrane protein functionalization of nanoparticles as a new tumor-targeting strategy

Nanoparticles have seen considerable popularity as effective tools for drug delivery. However, non-specific targeting continues to remain a challenge. Recently, biomimetic nanoparticles have emerged as an innovative solution that exploits biologically-derived components to improve therapeutic potential. Specifically, cell membrane proteins extracted from various cells (i.e., leukocytes, erythrocytes, platelets, mesenchymal stem cells, cancer) have shown considerable promise in bestowing nanoparticles with increased circulation and targeting efficacy. Traditional nanoparticles can be detected and removed by the immune system which significantly hinders their clinical success. Biomimicry has been proposed as a promising approach to overcome these limitations. In this review, we highlight the current trends in biomimetic nanoparticles and describe how they are being used to increase their chemotherapeutic effect in cancer treatment.

Epigallocatechin Gallate-Gold Nanoparticles Exhibit Superior Antitumor Activity Compared to Conventional Gold Nanoparticles: Potential Synergistic Interactions

Epigallocatechin gallate (EGCG) possesses significant antitumor activity and binds to laminin receptors, overexpressed on cancer cells, with high affinity. Gold nanoparticles (GNPs) serve as excellent drug carriers and protect the conjugated drug from enzymatic metabolization. Citrate-gold nanoparticles (C-GNPs) and EGCG-gold nanoparticles (E-GNPs) were synthesized by reduction methods and characterized with UV-visible spectroscopy, transmission electron microscopy (TEM), and dynamic light scattering (DLS). Cytotoxicity of citrate, EGCG, C-GNPs, and E-GNPs was evaluated by the water-soluble tetrazolium salt (WST-1) assay. Nanoparticle cellular uptake studies were performed by TEM and atomic absorption spectroscopy (AAS). Dialysis method was employed to assess drug release. Cell viability studies showed greater growth inhibition by E-GNPs compared to EGCG or C-GNPs. Cellular uptake studies revealed that, unlike C-GNPs, E-GNPs were taken up more efficiently by cancerous cells than noncancerous cells. We found that E-GNP nanoformulation releases EGCG in a sustained fashion. Furthermore, data showed that E-GNPs induced more apoptosis in cancer cells compared to EGCG and C-GNPs. From the mechanistic standpoint, we observed that E-GNPs inhibited the nuclear translocation and transcriptional activity of nuclear factor-kappaB (NF-κB) with greater potency than EGCG, whereas C-GNPs were only minimally effective. Altogether, our data suggest that E-GNPs can serve as potent tumor-selective chemotoxic agents.

Nanoparticle-Mediated Remodeling of the Tumor Microenvironment to Enhance Immunotherapy

Nanoscience has long been lauded as a method through which tumor-associated barriers could be overcome. As successful as cancer immunotherapy has been, limitations associated with the tumor microenvironment or side effects of systemic treatment have become more apparent. In this Review, we seek to lay out the therapeutic challenges associated with the tumor microenvironment and the ways in which nanoscience is being applied to remodel the tumor microenvironment and increase the susceptibility of many cancer types to immunotherapy. We detail the nanomedicines on the cutting edge of cancer immunotherapy and how their interactions with the tumor microenvironment make them more effective than systemically administered immunotherapies.

Research progress of novel inorganic nanometre materials carriers in nanomedicine for cancer diagnosis and treatment

Nanomedicine, as the new achievement in combination of nanotechnology and medical science, has the potential to accurately monitor tumor for early diagnosis and dramatically improve the targeted, long-lasting and combinational therapy. Compared with traditional chemotheraphy, nanomedicine would effectively improve the drug accumulation and controlled release in the tumor sites to improve the therapeutic effect. Recently, all kinds of nanomedicines are designed and synthesized for tumor diagnosis and treatment based on inorganic nanocarriers, such as quantum dots, gold nanoparticles, silicon nanoparticles and so on. They might be adjusted and promoted their properties by core-shell structure, surface modification and other strategies. In this review, the inorganic nanometre materials as nanodrug carriers applied in tumor diagnosis and treatment were summarized; nanodrug carriers design strategies and mechanisms of tumor diagnosis and treatment were introduced in detail, the future and several questions still need to resolve about inorganic nanodrugs in tumor diagnosis and treatment of clinical application was prospected.

Intracellular Delivery of Gold Nanocolloids Promoted by a Chemically Conjugated Anticancer Peptide

We report on the ability of a chemically synthesized anticancer peptide, SVS-1, to promote the rapid uptake of gold nanorods (AuNRs) and gold nanoparticles (AuNPs) by live HeLa cells. For this, AuNPs and AuNRs, surface ligated with a multicoordinating polymer that presents several amine groups per ligand, are simultaneously reacted with SVS-1 and Texas-Red dye; the latter allows fluorescence visualization of the nanocrystals. Using epifluorescence microscopy, we find that incubation of the SVS-1-conjugated AuNPs and AuNRs with a model cancer cell line yields extended staining throughout the cell cytoplasm, even at low conjugate concentrations (∼0.1 nM). Furthermore, uptake is specific to the SVS-1-conjugated nanocrystals. Additional endocytosis inhibition experiments, where cells have been incubated with the conjugates at 4 °C or in the presence of endocytic inhibitors, show that significant levels of conjugate uptake persist. These results combined indicate an uptake mechanism that does not necessarily rely on endocytosis, a promising finding with implications for the use of nanomaterials in the field of biology and nanomedicine.

Quantum Dots-Based Multifunctional Nano-Prodrug Fabricated by Ingenious Self-Assembly Strategies for Tumor Theranostic

The rapid developments of quantum dots (QDs)-based nanoagents for imaging tumor and tracking drug delivery have been proven to be reliable nanodiagnostic techniques. Although abundant types of QD nanoagents have been developed for fighting against cancer, it still is a challenge to control their quality and achieve prefect repetition due to the complicated synthetic steps. The precise intermolecular self-assembly (SA) may afford a facile and low-cost strategy for this challenge. Herein, a pH and H₂O₂ dual-sensitive Sb-cyclodextrin (CD)-doxorubicin (DOX) molecule was designed to construct a QD-based theranostic prodrug (named as Sb-CD-DOX-ZAISe/ZnS) via host-guest strategy (1st SA strategy), in which QDs water-transfer and drug-uploading were integrated well. That is, the nano-prodrug (NPD) inherited highly luminescent properties from "host" QDs for bioimaging, as well as environment sensitivities from "guest" Sb-CD-DOX for drug release. Experimental results indicate that the Sb-CD-DOX-ZAISe/ZnS exhibited effectively passive tumor-targeting and could provide clear imaging for malignant tumors in metaphase or advanced stages; meanwhile, after coating with folic acid (FA) through electric attraction (2nd SA strategy), the final Sb-CD-DOX-ZAISe/ZnS@FA NPD showed expected pH-controlled negative-to-positive charge reversal ability and a better curative effect compared with free DOX. Hence, fabricating nanocomposites by highly efficient self-assembly strategies is favorable toward inorganic nanoparticles-based prodrug delivery system for tumor-targeting theranostic.

Therapeutics for Inflammatory-Related Diseases Based on Plasmon-Activated Water: A Review

It is recognized that the properties of liquid water can be markedly different from those of bulk one when it is in contact with hydrophobic surfaces or is confined in nano-environments. Because our knowledge regarding water structure on the molecular level of dynamic equilibrium within a picosecond time scale is far from completeness all of water's conventionally known properties are based on inert "bulk liquid water" with a tetrahedral hydrogen-bonded structure. Actually, the strength of water's hydrogen bonds (HBs) decides its properties and activities. In this review, an innovative idea on preparation of metastable plasmon-activated water (PAW) with intrinsically reduced HBs, by letting deionized (DI) water flow through gold-supported nanoparticles (AuNPs) under resonant illumination at room temperature, is reported. Compared to DI water, the created stable PAW can scavenge free hydroxyl and 2,2-diphenyl-1-picrylhydrazyl radicals and effectively reduce NO release from lipopolysaccharide-induced inflammatory cells. Moreover, PAW can dramatically induce a major antioxidative Nrf2 gene in human gingival fibroblasts. This further confirms its cellular antioxidative and anti-inflammatory properties. In addition, innovatively therapeutic strategy of daily drinking PAW on inflammatory-related diseases based on animal disease models is demonstrated, examples being chronic kidney disease (CKD), chronic sleep deprivation (CSD), and lung cancer.

Origanum vulgare mediated green synthesis of biocompatible gold nanoparticles simultaneously possessing plasmonic, antioxidant and antimicrobial properties

Purpose

The leaves and flowering stem of Origanum vulgare contain essential oils, flavonoids, phenolic acids and anthocyanins. We propose a new, simple, one-pot, O. vulgare extract (OVE) mediated green synthesis method of biocompatible gold nanoparticles (AuNPs) possessing improved antioxidant, antimicrobial and plasmonic properties.

Materials and methods

Different concentrations of OVEs were used to reduce gold ions and to synthetize biocompatible spherical AuNPs. Their morphology and physical properties have been investigated by means of transmission electron microscopy, ultraviolet-visible absorption spectroscopy, photon correlation spectroscopy and Fourier transform infrared spectroscopy, whereas their plasmonic properties have been tested using surface-enhanced Raman spectroscopy (SERS). The antioxidant properties of nanoparticles (NPs) have been evaluated by 2,2-diphenyl-1-picrylhydrazyl radical scavenging assay, and the antimicrobial tests were performed using the disk diffusion assay. Their cytotoxicity has been assessed by means of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay.

Results

The experimental results confirmed the successful synthesis of biocompatible, spherical, plasmonic NPs having a mean diameter of ~40 nm and an outstanding aqueous stability. This new class of NPs exhibits a very good antioxidant activity and presents interesting inhibitory effects against Staphylococcus aureus and Candida albicans. Due to their plasmonic properties, AuNPs are used as SERS substrates for the detection of a test molecule (methylene blue) up to a concentration of 10^-7 M and a pharmaceutical compound (propranolol) in solution. Cytotoxicity assays revealed that AuNPs are better tolerated by normal human dermal fibroblast cells, while the melanoma cancer cells are more sensitive.

Conclusion

The biocompatible AuNPs synthetized using OVEs showed significant bactericidal and antimycotic activities, the most sensitive microorganisms being S. aureus and C. albicans, both commonly involved in various dermatological infections. Moreover, the significant antioxidant effect might recommend their use for protective and/or preventive effect in various skin inflammatory conditions, including the reduction in side effects in dermatological infections. Meanwhile, the as-synthesized biocompatible AuNPs can be successfully used as SERS substrates for the detection of pharmaceutical compounds in aqueous solutions.

Nanotechnology Strategies To Advance Outcomes in Clinical Cancer Care

Ongoing research into the application of nanotechnology for cancer treatment and diagnosis has demonstrated its advantages within contemporary oncology as well as its intrinsic limitations. The National Cancer Institute publishes the Cancer Nanotechnology Plan every 5 years since 2005. The most recent iteration helped codify the ongoing basic and translational efforts of the field and displayed its breadth with several evolving areas. From merely a technological perspective, this field has seen tremendous growth and success. However, an incomplete understanding of human cancer biology persists relative to the application of nanoscale materials within contemporary oncology. As such, this review presents several evolving areas in cancer nanotechnology in order to identify key clinical and biological challenges that need to be addressed to improve patient outcomes. From this clinical perspective, a sampling of the nano-enabled solutions attempting to overcome barriers faced by traditional therapeutics and diagnostics in the clinical setting are discussed. Finally, a strategic outlook of the future is discussed to highlight the need for next-generation cancer nanotechnology tools designed to address critical gaps in clinical cancer care.

Current Challenges of Cancer Anti-angiogenic Therapy and the Promise of Nanotherapeutics

With growing interest in cancer therapeutics, anti-angiogenic therapy has received considerable attention and is widely administered in several types of human cancers. Nonetheless, this type of therapy may induce multiple signaling pathways compared with cytotoxics and lead to worse outcomes in terms of resistance, invasion, metastasis, and overall survival (OS). Moreover, there are important challenges that limit the translation of promising biomarkers into clinical practice to monitor the efficiency of anti-angiogenic therapy. These pitfalls emphasize the urgent need for discovering alternative angiogenic inhibitors that target multiple angiogenic factors or developing a new drug delivery system for the current inhibitors. The great advantages of nanoparticles are their ability to offer effective routes that target the biological system and regulate different vital processes based on their unique features. Limited studies so far have addressed the effectiveness of nanoparticles in the normalization of the delicate balance between stimulating (pro-angiogenic) and inhibiting (anti-angiogenic) factors. In this review, we shed light on tumor vessels and their microenvironment and consider the current directions of anti-angiogenic and nanotherapeutic treatments. To the best of our knowledge, we consider an important effort in the understanding of anti-angiogenic agents (often a small volume of metals, nonmetallic molecules, or polymers) that can control the growth of new vessels.

Nanoparticles for modulating tumor microenvironment to improve drug delivery and tumor therapy

Tumor microenvironment (TME) plays a critical role in tumorigenesis, tumor invasion and metastasis. TME is composed of stroma, endothelial cells, pericytes, fibroblasts, smooth muscle cells, and immune cells, which is characterized by hypoxia, acidosis, and high interstitial fluid pressure. Due to the important role of TME, we firstly reviewed the composition of TME and discussed the impact of TME on tumor progression, drug and nanoparticle delivery. Next, we reviewed current strategies developed to modulate TME, including modulating tumor vasculature permeability, tumor associated macrophage phenotypes, tumor associated fibroblasts, tumor stroma components, tumor hypoxia, and multiple interventions simultaneously. Also, potential problems and future directions of TME modulation strategy have been discussed.

Diverse Applications of Nanomedicine

The design and use of materials in the nanoscale size range for addressing medical and health-related issues continues to receive increasing interest. Research in nanomedicine spans a multitude of areas, including drug delivery, vaccine development, antibacterial, diagnosis and imaging tools, wearable devices, implants, high-throughput screening platforms, etc. using biological, nonbiological, biomimetic, or hybrid materials. Many of these developments are starting to be translated into viable clinical products. Here, we provide an overview of recent developments in nanomedicine and highlight the current challenges and upcoming opportunities for the field and translation to the clinic.