Nanotechnology Approaches to Improving Cancer Immunotherapy

New advances in the research of clinical treatment and novel anticancer agents in tumor angiogenesis

In 1971, Folkman proposed that tumors could be limited to very small sizes by blocking angiogenesis. Angiogenesis is the generation of new blood vessels from pre-existing vessels, considered to be one of the important processes in tumor growth and metastasis. Angiogenesis is a complex process regulated by various factors and involves many secreted factors and signaling pathways. Angiogenesis is important in the transport of oxygen and nutrients to the tumor during tumor development. Therefore, inhibition of angiogenesis has become an important strategy in the clinical management of many solid tumors. Combination therapies of angiogenesis inhibitors with radiotherapy and chemotherapy are often used in clinical practice. In this article, we will review common targets against angiogenesis, the most common and up-to-date anti-angiogenic drugs and clinical treatments in recent years, including active ingredients from chemical and herbal medicines.

Engineering magnetic nano-manipulators for boosting cancer immunotherapy

Cancer immunotherapy has shown promising therapeutic results in the clinic, albeit only in a limited number of cancer types, and its efficacy remains less than satisfactory. Nanoparticle-based approaches have been shown to increase the response to immunotherapies to address this limitation. In particular, magnetic nanoparticles (MNPs) as a powerful manipulator are an appealing option for comprehensively regulating the immune system in vivo due to their unique magnetically responsive properties and high biocompatibility. This review focuses on assessing the potential applications of MNPs in enhancing tumor accumulation of immunotherapeutic agents and immunogenicity, improving immune cell infiltration, and creating an immunotherapy-sensitive environment. We summarize recent progress in the application of MNP-based manipulators to augment the efficacy of immunotherapy, by MNPs and their multiple magnetically responsive effects under different types of external magnetic field. Furthermore, we highlight the mechanisms underlying the promotion of antitumor immunity, including magnetically actuated delivery and controlled release of immunotherapeutic agents, tracking and visualization of immune response in real time, and magnetic regulation of innate/adaptive immune cells. Finally, we consider perspectives and challenges in MNP-based immunotherapy.

Trends and patterns in cancer nanotechnology research: A survey of NCI's caNanoLab and nanotechnology characterization laboratory

Cancer nanotechnologies possess immense potential as therapeutic and diagnostic treatment modalities and have undergone significant and rapid advancement in recent years. With this emergence, the complexities of data standards in the field are on the rise. Data sharing and reanalysis is essential to more fully utilize this complex, interdisciplinary information to answer research questions, promote the technologies, optimize use of funding, and maximize the return on scientific investments. In order to support this, various data-sharing portals and repositories have been developed which not only provide searchable nanomaterial characterization data, but also provide access to standardized protocols for synthesis and characterization of nanomaterials as well as cutting-edge publications. The National Cancer Institute's (NCI) caNanoLab is a dedicated repository for all aspects pertaining to cancer-related nanotechnology data. The searchable database provides a unique opportunity for data mining and the use of artificial intelligence and machine learning, which aims to be an essential arm of future research studies, potentially speeding the design and optimization of next-generation therapies. It also provides an opportunity to track the latest trends and patterns in nanomedicine research. This manuscript provides the first look at such trends extracted from caNanoLab and compares these to similar metrics from the NCI's Nanotechnology Characterization Laboratory, a laboratory providing preclinical characterization of cancer nanotechnologies to researchers around the globe. Together, these analyses provide insight into the emerging interests of the research community and rise of promising nanoparticle technologies.

Photoacoustic mediated multifunctional tumor antigen trapping nanoparticles inhibit the recurrence and metastasis of ovarian cancer by enhancing tumor immunogenicity

The hypoimmunogenicity of tumors is one of the main bottlenecks of cancer immunotherapy. Enhancing tumor immunogenicity can improve the efficacy of tumor immunotherapy by increasing antigen exposure and presentation, and establishing an inflammatory microenvironment. Here, a multifunctional antigen trapping nanoparticle with indocyanine green (ICG), aluminum hydroxide (Al(OH)3) and oxaliplatin (OXA) (PPIAO) has been developed for tumor photoacoustic/ultrasound dual-modality imaging and therapy. The combination of photothermal/photodynamic therapy and chemotherapy induced tumor antigen exposure and release through immunogenic death of tumor cells. A timely capture and storage of antigens by aluminum hydroxide enabled dendritic cells to recognize and present those antigens spatiotemporally. In an ovarian tumor model, the photoacoustic-mediated PPIAO NPs combination therapy achieved a transition from "cold tumor" to "hot tumor" that promoted more CD8+ T lymphocytes activation in vivo and intratumoral infiltration, and successfully inhibited the growth of primary and metastatic tumors. An in situ tumor vaccine effect was produced from the treated tumor tissue, assisting mice against the recurrence of tumor cells. This study provided a simple and effective personalized tumor vaccine strategy for better treatment of metastatic and recurrent tumors. The developed multifunctional tumor antigen trapping nanoparticles may be a promising nanoplatform for integrating multimodal imaging monitoring, tumor treatment, and tumor vaccine immunotherapy.

Co-delivery of Interleukin-12 and Doxorubicin Loaded Nano-delivery System for Enhanced Immunotherapy with Polarization toward M1-type Macrophages

Chemo-immunotherapy has gained increasing attention as one of the most promising combination therapy strategies to battle cancer. In this study, the therapeutic nanoparticles (TNPs) co-delivering doxorubicin (DOX) and IL-12 (IL-12) were developed for chemo-immunotherapy combination therapy on liver cancer. TNPs were synthesized based on the ionic interactions between cationic chitosan (Ch) and anionic poly-(glutamic acid) (PGA). DOX and IL-12 loaded in TNPs presented prolonged circulation in blood, efficient accumulation in tumors, and internalization in tumor cells. After that, DOX and IL-12 were co-released in the tumor microenvironment. The locally responsive property of TNPs could subsequently re-educate macrophages. More significantly, TNPs with no obvious side effects can remarkably inhibit the H22 tumor growth in vivo. A low dosage of loaded IL-12 in TNPs can effectively polarize macrophages toward the M1 phenotype to reduce tumor burden, further enhancing the antitumor efficacy. Our results suggest that the self-stabilized TNPs could be a secure and effective drug carrier for intravenous administration when deprived of protective agents.

Recent advances in porous nanomaterials-based drug delivery systems for cancer immunotherapy

Cancer immunotherapy is a novel therapeutic regimen because of the specificity and durability of immune modulations to treat cancers. Current cancer immunotherapy is limited by some barriers such as poor response rate, low tumor specificity and systemic toxicities. Porous nanomaterials (PNMs) possess high loading capacity and tunable porosity, receiving intense attention in cancer immunotherapy. Recently, novel PNMs based drug delivery systems have been employed in antitumor immunotherapy to enhance tissue or organ targeting and reduce immune-related adverse events. Herein, we summarize the recent progress of PNMs including inorganic, organic, and organic–inorganic hybrid ones for cancer immunotherapy. The design of PNMs and their performance in cancer immunotherapy are discussed in detail, with a focus on how those designs can address the challenges in current conventional immunotherapy. Lastly, we present future directions of PNMs for cancer immunotherapy including the challenges and research gaps, providing new insights about the design of PNMs for efficient cancer immunotherapy with better performance as powerful weapons against tumors. Finally, we discussed the relevant challenges that urgently need to be addressed in clinical practice, coupled with corresponding solutions to these problems.

Applications of Extracellular Vesicles in Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC) is the most aggressive and refractory subtype of breast cancer, often occurring in younger patients with poor clinical prognosis. Given the current lack of specific targets for effective intervention, the development of better treatment strategies remains an unmet medical need. Over the last decade, the field of extracellular vesicles (EVs) has grown tremendously, offering immense potential for clinical diagnosis/prognosis and therapeutic applications. While TNBC-EVs have been shown to play an important role in tumorigenesis, chemoresistance and metastasis, they could be repurposed as potential biomarkers for TNBC diagnosis and prognosis. Furthermore, EVs from various cell types can be utilized as nanoscale drug delivery systems (NDDS) for TNBC treatment. Remarkably, EVs generated from specific immune cell subsets have been shown to delay solid tumour growth and reduce tumour burden, suggesting a new immunotherapy approach for TNBC. Intrinsically, EVs can cross the blood-brain barrier (BBB), which holds great potential to treat the brain metastases diagnosed in one third of TNBC patients that remains a substantial clinical challenge. In this review, we present the most recent applications of EVs in TNBC as diagnostic/prognostic biomarkers, nanoscale drug delivery systems and immunotherapeutic agents, as well as discuss the associated challenges and future directions of EVs in cancer immunotherapy.

The pathogenic biomarker alcohol dehydrogenase protein is involved in Bacillus cereus virulence and survival against host innate defence

Bacillus cereus is a spore forming bacteria recognized among the leading agents responsible for foodborne outbreaks in Europe. B. cereus is also gaining notoriety as an opportunistic human pathogen inducing local and systemic infections. The real incidence of such infection is likely underestimated and information on genetic and phenotypic characteristics of the incriminated strains is generally scarce. We have recently analyzed a large strain collection of varying pathogenic potential. Screening for biomarkers to differentiate among clinical and non-clinical strains, a gene encoding an alcohol dehydrogenase-like protein was identified among the leading candidates. This family of proteins has been demonstrated to be involved in the virulence of several bacterial species. The relevant gene was knocked out to elucidate its function with regards to resistance to host innate immune response, both in vitro and in vivo. Our results demonstrate that the adhB gene plays a significant role in resistance to nitric oxide and oxidative stress in vitro, as well as its pathogenic ability with regards to in vivo toxicity. These properties may explain the pathogenic potential of strains carrying this newly identified virulence factor.

Tumor microenvironment: a prospective target of natural alkaloids for cancer treatment

Malignant tumor has become one of the major diseases that seriously endangers human health. Numerous studies have demonstrated that tumor microenvironment (TME) is closely associated with patient prognosis. Tumor growth and progression are strongly dependent on its surrounding tumor microenvironment, because the optimal conditions originated from stromal elements are required for cancer cell proliferation, invasion, metastasis and drug resistance. The tumor microenvironment is an environment rich in immune/inflammatory cells and accompanied by a continuous, gradient of hypoxia and pH. Overcoming immunosuppressive environment and boosting anti-tumor immunity may be the key to the prevention and treatment of cancer. Most traditional Chinese medicine have been proved to have good anti-tumor activity, and they have the advantages of better therapeutic effect and few side effects in the treatment of malignant tumors. An increasing number of studies are giving evidence that alkaloids extracted from traditional Chinese medicine possess a significant anticancer efficiency via regulating a variety of tumor-related genes, pathways and other mechanisms. This paper reviews the anti-tumor effect of alkaloids targeting tumor microenvironment, and further reveals its anti-tumor mechanism through the effects of alkaloids on different components in tumor microenvironment.

The Application of and Strategy for Gold Nanoparticles in Cancer Immunotherapy

Immunotherapy of malignant tumor is a verified and crucial anti-tumor strategy to help patients with cancer for prolonging prognostic survival. It is a novel anticancer tactics that activates the immune system to discern and damage cancer cells, thereby prevent them from proliferating. However, immunotherapy still faces many challenges in view of clinical efficacy and safety issues. Various nanomaterials, especially gold nanoparticles (AuNPs), have been developed not only for anticancer treatment but also for delivering antitumor drugs or combining other treatment strategies. Recently, some studies have focused on AuNPs for enhancing cancer immunotherapy. In this review, we summarized how AuNPs applicated as immune agents, drug carriers or combinations with other immunotherapies for anticancer treatment. AuNPs can not only act as immune regulators but also deliver immune drugs for cancer. Therefore, AuNPs are candidates for enhancing the efficiency and safety of cancer immunotherapy.

The potential antimalarial efficacy of hemocompatible silver nanoparticles from Artemisia species against P. falciparum parasite

Malaria represents one of the most common infectious diseases which becoming an impellent public health problem worldwide. Antimalarial classical medications include quinine-based drugs, like chloroquine, and artesunate, a derivative of artemisinin, a molecule found in the plant Artemisia annua. Such therapeutics are very effective but show heavy side effects like drug resistance. In this study, "green" silver nanoparticles (AgNPs) have been prepared from two Artemisia species (A. abrotanum and A. arborescens), traditionally used in folk medicine as a remedy for different conditions, and their potential antimalarial efficacy have been assessed. AgNPs have been characterized by UV-Vis, dynamic light scattering and zeta potential, FTIR, XRD, TEM and EDX. The structural characterization has demonstrated the spheroidal shape of nanoparticles and dimensions under 50 nm, useful for biomedical studies. Zeta potential analysis have shown the stability and dispersion of green AgNPs in aqueous medium without aggregation. AgNPs hemocompatibility and antimalarial activity have been studied in Plasmodium falciparum cultures in in vitro experiments. The antiplasmodial effect has been assessed using increasing doses of AgNPs (0.6 to 7.5 μg/mL) on parasitized red blood cells (pRBCs). Obtained data showed that the hemocompatibility of AgNPs is related to their synthetic route and depends on the administered dose. A. abrotanum-AgNPs (1) have shown the lowest percentage of hemolytic activity on pRBCs, underlining their hemocompatibility. These results are in accordance with the lower levels of parasitemia observed after A. abrotanum-AgNPs (1) treatment respect to A. arborescens-AgNPs (2), and AgNPs (3) derived from a classical chemical synthesis. Moreover, after 24 and 48 hours of A. abrotanum-AgNPs (1) treatment, the parasite growth was locked in the ring stage, evidencing the effect of these nanoparticles to hinder the maturation of P. falciparum. The anti-malarial activity of A. abrotanum-AgNPs (1) on pRBCs was demonstrated to be higher than that of A. arborescens-AgNPs (2).

Recent advances in combinatorial cancer therapy via multifunctionalized gold nanoparticles

The diverse behavior of nanogold in the therapeutic field is related to its unique size and shape. Nanogold offers improvements in modern diagnostic and therapeutic implications, increases disease specificity and targeted drug delivery, and is relatively economical compared with other chemotherapeutic protocols. The diagnosis of cancer and photothermal therapy improve drastically with the implementation of nanotechnology. Different types of nanoparticles, that is, gold silica nanoshells, nanorods and nanospheres of diverse shapes and geometries, are used widely in the photothermal therapy of cancerous cells and nodules. Numerous reviews have been published on the therapeutic applications of gold nanoparticles, but studies on combinatorial applications of nanogold in cancer therapy are limited. This review focuses on the combinatorial cancer therapy using optical properties of nanogold with different shapes and geometries, and their therapeutic applications in cancer diagnosis, photothermal therapy, cancer imaging and targeted drug delivery.

Microfluidic-Based Immunomodulation of Immune Cells Using Upconversion Nanoparticles in Simulated Blood Vessel-Tumor System

The goal of cancer immunotherapy is the selective killing of malignant cells by the cooperated efforts of immune cells at the primary and secondary sites. Here, we developed folic acid and secondary lymphoid tissue chemokine-loaded mesoporous silica-modified upconversion nanoparticle construct as a targeting, delivery, and imaging system to attract immune cells to folate receptor-expressing tumor cells. The effectiveness of the nanoparticles in targeting dendritic cells and T cells to the tumor compartment was tested in a vasculature-tumor interface model constructed from the co-culture of endothelial cells and ovarian cancer cells, in different interconnected channels in a microfluidic device. In comparison to the unconjugated nanoparticles, the folic acid-conjugated nanoparticles efficiently diffuse across the engineered blood vessel and specifically target the folate receptor-expressing ovarian cancer cells. The developed microfluidic platform was further used to demonstrate increased dendritic cell and T cell migration toward the ovarian cancer cell channel induced by the presence of the chemokine- and folic acid-loaded nanoparticles. The nanoparticle construct did not exhibit any significant cyto- and hemotoxicity. This proof of concept showed the potential of the nanoparticles to target cancer cells as well as to recruit dendritic cells and T cells to tumor sites to augment the weak host immune response.

Interactions of Nanoparticles and Biosystems: Microenvironment of Nanoparticles and Biomolecules in Nanomedicine

Nanotechnology is a multidisciplinary science covering matters involving the nanoscale level that is being developed for a great variety of applications. Nanomedicine is one of these attractive and challenging uses focused on the employment of nanomaterials in medical applications such as drug delivery. However, handling these nanometric systems require defining specific parameters to establish the possible advantages and disadvantages in specific applications. This review presents the fundamental factors of nanoparticles and its microenvironment that must be considered to make an appropriate design for medical applications, mainly: (i) Interactions between nanoparticles and their biological environment, (ii) the interaction mechanisms, (iii) and the physicochemical properties of nanoparticles. On the other hand, the repercussions of the control, alter and modify these parameters in the biomedical applications. Additionally, we briefly report the implications of nanoparticles in nanomedicine and precision medicine, and provide perspectives in immunotherapy, which is opening novel applications as immune-oncology.

Tailoring Nanomaterials for Targeting Tumor-Associated Macrophages

Advances in the field of nanotechnology together with an increase understanding of tumor immunology have paved the way for the development of more personalized cancer immuno-nanomedicines. Nanovehicles, due to their specific physicochemical properties, are emerging as key translational moieties in tackling tumor-promoting, M2-like tumor-associated macrophages (TAMs). Cancer immuno-nanomedicines target TAMs primarily by blocking M2-like TAM survival or affecting their signaling cascades, restricting macrophage recruitment to tumors and re-educating tumor-promoting M2-like TAMs to the tumoricidal, M1-like phenotype. Here, the TAM effector mechanisms and strategies for targeting TAMs are summarized, followed by a focus on the mechanistic considerations in the development of novel immuno-nanomedicines. Furthermore, imaging TAMs with nanoparticles so as to forecast a patient's clinical outcome, describing treatment options, and observing therapy responses is also discussed. At present, strategies that target TAMs are being investigated not only at the basic research level but also in early clinical trials. The significance of TAM-targeting biomaterials is highlighted, with the goal of facilitating future clinical translation.

Antioxidant and toxicity studies of biosynthesized cerium oxide nanoparticles in rats

PURPOSE

The purpose of this study was to investigate the acute toxic potential of cerium oxide nanoparticles (CNPs) synthesized by pullulan in adult male Wistar rats.

PATIENTS AND METHODS

Thirty male Wistar rats randomly were divided into five experimental groups of six animals each. The animals were received 50, 100, 200, and 400 mg/kg CNPs for 14 consecutive days. At the end of the experiment, the rats were euthanized and histopathological evaluation of the liver and renal tissues, as well ass, the markers of serum oxidative stress including thiobarbituric acid reactive substances, total sulfhydryl content, and antioxidant capacity (using ferric reducing/antioxidant power assay) were assessed. Hematological parameters and the activity of liver function enzymes were also measured.

RESULTS

The results of this study showed that CNPs caused no significant changes in the activity of liver enzymes, hepatic and renal histopathology and hematological parameters, while significantly improved serum redox status.

CONCLUSION

Acute administration of pullulan-mediated CNPs is safe and possess antioxidant activity.

Integrating nanomedicine into clinical radiotherapy regimens

While the advancement of clinical radiotherapy was driven by technological innovations throughout the 20th century, continued improvement relies on rational combination therapies derived from biological insights. In this review, we highlight the importance of combination radiotherapy in the era of precision medicine. Specifically, we survey and summarize the areas of research where improved understanding in cancer biology will propel the field of radiotherapy forward by allowing integration of novel nanotechnology-based treatments.

Vγ9Vδ2 T Cells as Strategic Weapons to Improve the Potency of Immune Checkpoint Blockade and Immune Interventions in Human Myeloma

The advent of immune checkpoint (ICP) blockade has introduced an unprecedented paradigm shift in the treatment of cancer. Though very promising, there is still a substantial proportion of patients who do not respond or develop resistance to ICP blockade. In vitro and in vivo models are eagerly needed to identify mechanisms to maximize the immune potency of ICP blockade and overcome primary and acquired resistance to ICP blockade. Vγ9Vδ2 T cells isolated from the bone marrow (BM) from multiple myeloma (MM) are excellent tools to investigate the mechanisms of resistance to PD-1 blockade and to decipher the network of mutual interactions between PD-1 and the immune suppressive tumor microenvironment (TME). Vγ9Vδ2 T cells can easily be interrogated to dissect the progressive immune competence impairment generated in the TME by the long-lasting exposure to myeloma cellss. BM MM Vγ9Vδ2 T cells are PD-1⁺ and anergic to phosphoantigen (pAg) stimulation; notably, single agent PD-1 blockade is insufficient to fully recover their anti-tumor activity in vitro indicating that additional players are involved in the anergy of Vγ9Vδ2 T cells. In this mini-review we will discuss the value of Vγ9Vδ2 T cells as investigational tools to improve the potency of ICP blockade and immune interventions in MM.