Designer vaccine nanodiscs for personalized cancer immunotherapy

Pancreatic tumor eradication via selective Pin1 inhibition in cancer-associated fibroblasts and T lymphocytes engagement

Cancer associated fibroblasts (CAFs) support tumors via multiple mechanisms, including maintaining the immunosuppressive tumor microenvironment and limiting infiltration of immune cells. The prolyl isomerase Pin1, whose overexpression in CAFs has not been fully profiled yet, plays critical roles in tumor initiation and progression. To decipher effects of selective Pin1 inhibition in CAFs on pancreatic cancer, here we formulate a DNA-barcoded micellular system (DMS) encapsulating the Pin1 inhibitor AG17724. DMS functionalized with CAF-targeting anti-FAP-α antibodies (antiCAFs-DMS) can selectively inhibit Pin1 in CAFs, leading to efficacious but transient tumor growth inhibition. We further integrate DNA aptamers (AptT), which can engage CD8+ T lymphocytes, to obtain a bispecific antiCAFs-DMS-AptT system. AntiCAFs-DMS-AptT inhibits tumor growth in subcutaneous and orthotopic pancreatic cancer models.

Pharmacological inhibition of the prolyl isomerase PIN1, highly expressed in cancer cells and cancer associated fibroblasts (CAF), has been proposed for cancer therapy. Here the authors report the design of a DNA-barcoded micellular system functionalized with antibodies targeting CAFs and a T cell recruiting aptamer to deliver the PIN1 inhibitor AG17724, showing antitumor response in preclinical models of pancreatic cancer.

Nanocarriers based on bacterial membrane materials for cancer vaccine delivery

Here we present a protocol for the construction and use of two types of nanocarrier based on bacterial membrane materials for cancer vaccine delivery. Cancer vaccines induce tumor regression through triggering the specific T-cell responses against tumor neoantigens, a process that can be enhanced by nanocarrier delivery. Inspired by the body's natural immune defenses against bacterial invasion, we have developed two different types of nanocarrier based on bacterial membrane materials, which employ genetically engineered outer-membrane vesicles (OMVs), or hybrid membrane vesicles containing bacterial cytoplasmic membrane, respectively. The OMV-based nanocarriers can rapidly display different tumor antigens through the surface modified Plug-and-Display system, suitable for customized cancer vaccines when the tumor neoantigens can be identified. The hybrid membrane-based nanocarriers are prepared through fusion of the bacterial cytoplasmic membrane and the primary tumor cell membrane from surgically removed tumor tissues, possessing unique advantages as personalized cancer vaccines when the neoantigens are not readily available. Compared with chemically synthesized nanocarriers such as liposomes and polymer without intrinsic adjuvant properties, owing to the large amounts of pathogen-associated molecular patterns, the two nanocarriers can activate the antigen-presenting cells while delivering multiple antigens, thus inducing effective antigen presentation and robust adaptive immune activation. Excluding bacterial culture and tumor tissue collection, the preparation of OMV- and hybrid membrane-based nanocarriers takes ~8 h and 10 h for tumor vaccine construction, respectively. We also detail how to use these nanocarriers to create cancer nanovaccines and evaluate their immunostimulatory and antitumor effects.

Multiepitope supramolecular peptide nanofibers eliciting coordinated humoral and cellular antitumor immune responses

Subunit vaccines inducing antibodies against tumor-specific antigens have yet to be clinically successful. Here, we use a supramolecular α-helical peptide nanofiber approach to design epitope-specific vaccines raising simultaneous B cell, CD8⁺ T cell, and CD4⁺ T cell responses against combinations of selected epitopes and show that the concurrent induction of these responses generates strong antitumor effects in mice, with significant improvements over antibody or CD8⁺ T cell-based vaccines alone, in both prophylactic and therapeutic subcutaneous melanoma models. Nanofiber vaccine-induced antibodies mediated in vitro tumoricidal antibody-dependent cellular cytotoxicity (ADCC) and antibody-dependent cellular phagocytosis (ADCP). The addition of immune checkpoint and phagocytosis checkpoint blockade antibodies further improved the therapeutic effect of the nanofiber vaccines against murine melanoma. These findings highlight the potential clinical benefit of vaccine-induced antibody responses for tumor treatments, provided that they are accompanied by simultaneous CD8⁺ and CD4⁺ responses, and they illustrate a multiepitope cancer vaccine design approach using supramolecular nanomaterials.

Therapeutic Cancer Vaccines—Antigen Discovery and Adjuvant Delivery Platforms

For decades, vaccines have played a significant role in protecting public and personal health against infectious diseases and proved their great potential in battling cancers as well. This review focused on the current progress of therapeutic subunit vaccines for cancer immunotherapy. Antigens and adjuvants are key components of vaccine formulations. We summarized several classes of tumor antigens and bioinformatic approaches of identification of tumor neoantigens. Pattern recognition receptor (PRR)-targeting adjuvants and their targeted delivery platforms have been extensively discussed. In addition, we emphasized the interplay between multiple adjuvants and their combined delivery for cancer immunotherapy.

Image-guided/improved diseases management: From immune-strategies and beyond

Timely and accurate assessment and diagnosis are extremely important and beneficial for all diseases, especially for some of the major human disease, such as cancers, cardiovascular diseases, infectious diseases, and neurodegenerative diseases. Limited by the variable disease microenvironment, early imperceptible symptoms, complex immune system interactions, and delayed clinical phenotypes, disease diagnosis and treatment are difficult in most cases. Molecular imaging (MI) techniques can track therapeutic drugs and disease sites in vivo and in vitro in a non-invasive, real-time and visible strategies. Comprehensive visual imaging and quantitative analysis based on different levels can help to clarify the disease process, pathogenesis, drug pharmacokinetics, and further evaluate the therapeutic effects. This review summarizes the application of different MI techniques in the diagnosis and treatment of these major human diseases. It is hoped to shed a light on the development of related technologies and fields.

In vivo fate and intracellular trafficking of vaccine delivery systems

With the pandemic of severe acute respiratory syndrome coronavirus 2, vaccine delivery systems emerged as a core technology for global public health. Given that antigen processing takes place inside the cell, the intracellular delivery and trafficking of a vaccine antigen will contribute to vaccine efficiency. Investigations focusing on the in vivo behavior and intracellular transport of vaccines have improved our understanding of the mechanisms relevant to vaccine delivery systems and facilitated the design of novel potent vaccine platforms. In this review, we cover the intracellular trafficking and in vivo fate of vaccines administered via various routes and delivery systems. To improve immune responses, researchers have used various strategies to modulate vaccine platforms and intracellular trafficking. In addition to progress in vaccine trafficking studies, the challenges and future perspectives for designing next-generation vaccines are discussed.

Nanomaterial-Based Drug Delivery System Targeting Lymph Nodes

The lymphatic system plays an indispensable role in humoral balance, lipid metabolism, and immune regulation. The lymph nodes (LNs) are known as the primary sites of tumor metastasis and the metastatic LNs largely affected the prognosis of the patiens. A well-designed lymphatic-targeted system favors disease treatment as well as vaccination efficacy. In recent years, development of nanotechnologies and emerging biomaterials have gained increasing attention in developing lymph-node-targeted drug-delivery systems. By mimicking the endogenous macromolecules or lipid conjugates, lymph-node-targeted nanocarries hold potential for disease diagnosis and tumor therapy. This review gives an introduction to the physiological functions of LNs and the roles of LNs in diseases, followed by a review of typical lymph-node-targeted nanomaterial-based drug-delivery systems (e.g., liposomes, micelles, inorganic nanomaterials, hydrogel, and nanocapsules). Future perspectives and conclusions concerned with lymph-node-targeted drug-delivery systems are also provided.

Rational Vaccinology: Harnessing Nanoscale Chemical Design for Cancer Immunotherapy

Cancer immunotherapy is a powerful treatment strategy that mobilizes the immune system to fight disease. Cancer vaccination is one form of cancer immunotherapy, where spatiotemporal control of the delivery of tumor-specific antigens, adjuvants, and/or cytokines has been key to successfully activating the immune system. Nanoscale materials that take advantage of chemistry to control the nanoscale structural arrangement, composition, and release of immunostimulatory components have shown significant promise in this regard. In this Outlook, we examine how the nanoscale structure, chemistry, and composition of immunostimulatory compounds can be modulated to maximize immune response and mitigate off-target effects, focusing on spherical nucleic acids as a model system. Furthermore, we emphasize how chemistry and materials science are driving the rational design and development of next-generation cancer vaccines. Finally, we identify gaps in the field that should be addressed moving forward and outline future directions to galvanize researchers from multiple disciplines to help realize the full potential of this form of cancer immunotherapy through chemistry and rational vaccinology.

Nanotechnology-Based Diagnostic and Therapeutic Strategies for Neuroblastoma

Neuroblastoma (NB), as the most common extracranial solid tumor in childhood, is one of the critical culprits affecting children's health. Given the heterogeneity and invisibility of NB tumors, the existing diagnostic and therapeutic approaches are inadequate and ineffective in early screening and prognostic improvement. With the rapid innovation and development of nanotechnology, nanomedicines have attracted widespread attention in the field of oncology research for their excellent physiological and chemical properties. In this review, we first explored the current common obstacles in the diagnosis and treatment of NB. Then we comprehensively summarized the advancements in nanotechnology-based multimodal synergistic diagnosis and treatment of NB and elucidate the underlying mechanisms. In addition, a discussion of the pending challenges in biocompatibility and toxicity of nanomedicine was conducted. Finally, we described the development and application status of nanomaterials against some of the recognized targets in the field of NB research, and pointed out prospects for nanomedicine-based precision diagnosis and therapy of NB.

Lenalidomide bypasses CD28 co-stimulation to reinstate PD-1 immunotherapy by activating Notch signaling

Programmed cell death protein 1 (PD-1) checkpoint blockade therapy requires the CD28 co-stimulatory receptor for CD8⁺ T cell expansion and cytotoxicity. However, CD28 expression is frequently lost in exhausted T cells and during immune senescence, limiting the clinical benefits of PD-1 immunotherapy in individuals with cancer. Here, using a cereblon knockin mouse model that regains in vivo T cell response to lenalidomide, an immunomodulatory imide drug, we show that lenalidomide reinstates the anti-tumor activity of CD28-deficient CD8⁺ T cells after PD-1 blockade. Lenalidomide redirects the CRL4^Crbn ubiquitin ligase to degrade Ikzf1 and Ikzf3 in T cells and unleashes paracrine interleukin-2 (IL-2) and intracellular Notch signaling, which collectively bypass the CD28 requirement for activation of intratumoral CD8⁺ T cells and inhibition of tumor growth by PD-1 blockade. Our results suggest that PD-1 immunotherapy can benefit from a lenalidomide combination when treating solid tumors infiltrated with abundant CD28^- T cells.

Tracing New Landscapes in the Arena of Nanoparticle-Based Cancer Immunotherapy

Over the past two decades, unique and comprehensive cancer treatment has ushered new hope in the holistic management of the disease. Cancer immunotherapy, which harnesses the immune system of the patient to attack the cancer cells in a targeted manner, scores over others by being less debilitating compared to the existing treatment strategies. Significant advancements in the knowledge of immune surveillance in the last few decades have led to the development of several types of immune therapy like monoclonal antibodies, cancer vaccines, immune checkpoint inhibitors, T-cell transfer therapy or adoptive cell therapy (ACT) and immune system modulators. Intensive research has established cancer immunotherapy to be a safe and effective method for improving survival and the quality of a patient’s life. However, numerous issues with respect to site-specific delivery, resistance to immunotherapy, and escape of cancer cells from immune responses, need to be addressed for expanding and utilizing this therapy as a regular mode in the clinical treatment. Development in the field of nanotechnology has augmented the therapeutic efficiency of treatment modalities of immunotherapy. Nanocarriers could be used as vehicles because of their advantages such as increased surface areas, targeted delivery, controlled surface and release chemistry, enhanced permeation and retention effect, etc. They could enhance the function of immune cells by incorporating immunomodulatory agents that influence the tumor microenvironment, thus enabling antitumor immunity. Robust validation of the combined effect of nanotechnology and immunotherapy techniques in the clinics has paved the way for a better treatment option for cancer than the already existing procedures such as chemotherapy and radiotherapy. In this review, we discuss the current applications of nanoparticles in the development of ‘smart’ cancer immunotherapeutic agents like ACT, cancer vaccines, monoclonal antibodies, their site-specific delivery, and modulation of other endogenous immune cells. We also highlight the immense possibilities of using nanotechnology to accomplish leveraging the coordinated and adaptive immune system of a patient to tackle the complexity of treating unique disease conditions and provide future prospects in the field of cancer immunotherapy.

Improvement of Thermal Stability of Amphipathic Peptide-Phospholipid Nanodiscs via Lateral Association of α-Helices by Disulfide Cross-Linking

Amphipathic α-helical peptides have been reported to form discoidal particles or nanodiscs with phospholipids, in which a lipid bilayer patch is encircled by peptides. Peptide-based nanodiscs have broad applicability because of their ease of preparation, size flexibility, and structural plasticity. We previously revealed that the nanodiscs formed by apolipoprotein-A-I-derived peptide 18A showed temperature-dependent structural destabilization above the gel-to-liquid-crystalline phase transition temperature of the lipid bilayer. It has been suggested that this destabilization is due to the migration of peptides bound to the edge of the discs to the bilayer surface. In this study, we designed a peptide that could stabilize nanodisc structures against the phase transition of lipid bilayers by disulfide cross-linking of peptides. An 18A-dimer cross-linked by a proline residue, 37pA (Ac-18A-P-18A-CONH₂), also showed thermal destabilization of nanodiscs like 18A. However, cross-linking the sides of the two α-helices of the cysteine-substituted analogue 37pA-C2 with disulfide bonds led to the formation of nanodiscs that were more stable to temperature changes. This stabilizing effect was mainly due to the formation of a cyclic 37pA-C2 monomer by intramolecular disulfide cross-linking. These results suggest that the lateral association of two α-helices, which is the basis of the double-belt structure, is an important factor for the implementation of stable nanodiscs. The results of this study will help in development of more stable nanoparticles with membrane proteins in the future.

Bioinspired vaccines to enhance MHC class-I antigen cross-presentation

Cross-presentation of exogenous antigen on MHC class-I is a crucial process for generating a CD8⁺ T cell response, and is therefore an important design consideration in the development of T-cell-engaging vaccines against viruses, intracellular bacteria, and cancers. Here, we briefly summarize known cross-presentation pathways and highlight how synthetic vaccines can be engineered to enhance MHC-I presentation of exogenous peptide and protein antigens by professional antigen-presenting cells (APCs). In particular, we summarize how molecular engineering and nanotechnology are being harnessed to enhance antigen delivery to lymph nodes and to cross-presenting dendritic cells, to bypass endosomal trafficking of exogenous antigen to promote delivery of antigen to the cytosol of APCs, and to coordinate the delivery of antigen with immune-stimulating adjuvants that can act synergistically to augment antigen cross-presentation.

Local scaffold-assisted delivery of immunotherapeutic agents for improved cancer immunotherapy

Cancer immunotherapy, which reprograms a patient's own immune system to eradicate cancer cells, has been demonstrated as a promising therapeutic strategy clinically. Immune checkpoint blockade (ICB) therapies, cytokine therapies, cancer vaccines, and chimeric antigen receptor (CAR) T cell therapies utilize immunotherapy techniques to relieve tumor immune suppression and/or activate cellular immune responses to suppress tumor growth, metastasis and recurrence. However, systemic administration is often hampered by limited drug efficacy and adverse side effects due to nonspecific tissue distribution of immunotherapeutic agents. Advancements in local scaffold-based delivery systems facilitate a controlled release of therapeutic agents into specific tissue sites through creating a local drug reservoir, providing a potent strategy to overcome previous immunotherapy limitations by improving site-specific efficacy and minimizing systemic toxicity. In this review, we summarized recent advances in local scaffold-assisted delivery of immunotherapeutic agents to reeducate the immune system, aiming to amplify anticancer efficacy and minimize immune-related adverse events. Additionally, the challenges and future perspectives of local scaffold-assisted cancer immunotherapy for clinical translation and applications are discussed.

Single-component nanodiscs via the thermal folding of amphiphilic graft copolymers with the adjusted flexibility of the main chain

Nanodiscs have attracted considerable attention as structural scaffolds for membrane-protein research and as biomaterials in e.g. drug-delivery systems. However, conventional disc-fabrication methods are usually laborious, and disc fabrication via the self-assembly of amphiphiles is difficult. Herein, we report the formation of polymer nanodiscs based on the self-assembly of amphiphilic graft copolymers by adjusting the persistence length of the main chain. Amphiphilic graft copolymers with a series of different main-chain persistence lengths were prepared and these formed, depending on the persistence length, either rods, discs, or vesicles. Notably, polymer nanodiscs were formed upon heating a chilled polymer solution without the need for any additives, and the thus obtained nanodiscs were used to solubilize a membrane protein during cell-free protein synthesis. Given the simplicity of this disc-fabrication method and the ability of these discs to solubilize membrane proteins, this study considerably expands the fundamental and practical scope of graft-copolymer nanodiscs and demonstrates their utility as tools for studying the structure and function of membrane proteins.

Drug delivery for metabolism targeted cancer immunotherapy

Drug delivery vehicles have made a great impact on cancer immunotherapies in clinics and pre-clinical research. Notably, the science of delivery of cancer vaccines and immunotherapeutics, modulating immune cell functions has inspired development of several successful companies and clinical products. Interestingly, these drug delivery modalities not only modulate the function of immune cells (often quantified at the mRNA and protein levels), but also modulate the metabolism of these cells. Specifically, cancer immunotherapy often leads to activation of different immune cells such as dendritic cells, macrophages and T cells, which is driven by energy metabolism of these cells. Recently, there has been a great excitement about interventions that can directly modulate the energy metabolism of these immune cells and thus affect their function and in turn lead to a robust cancer immune response. Here we review few strategies that have been tested in clinic and pre-clinical research for generating effective metabolism-associated cancer therapies and immunotherapies.

Two-Pronged Intracellular Co-Delivery of Antigen and Adjuvant for Synergistic Cancer Immunotherapy

Nanovaccines have emerged as promising alternatives or complements to conventional cancer treatments. Despite the progresses, specific co-delivery of antigen and adjuvant to their corresponding intracellular destinations for maximizing the activation of antitumor immune responses remains a challenge. Herein, a lipid-coated iron oxide nanoparticle is delivered as nanovaccine (IONP-C/O@LP) that can co-deliver peptide antigen and adjuvant (CpG DNA) into cytosol and lysosomes of dendritic cells (DCs) through both membrane fusion and endosome-mediated endocytosis. Such two-pronged cellular uptake pattern enables IONP-C/O@LP to synergistically activate immature DCs. Iron oxide nanoparticle also exhibits adjuvant effects by generating intracellular reactive oxygen species, which further promotes DC maturation. IONP-C/O@LP accumulated in the DCs of draining lymph nodes effectively increases the antigen-specific T cells in both tumor and spleen, inhibits tumor growth, and improves animal survival. Moreover, it is demonstrated that this nanovaccine is a general platform of delivering clinically relevant peptide antigens derived from human papilloma virus 16 to trigger antigen-specific immune responses in vivo.

Lipid-based nanoparticles for treatment of cancer

Investigators were continuously creating novel nanotechnologies to address unmet requirements throughout the administration of therapeutic medicines & imaging agents for cancer treatment & diagnostics, appropriately. LNPs(Lipid nanoparticles) are legitimate particulates (approx. 100 nm in size) gathered from various lipid as well as other biochemical compounds which overall functionality to resolve biological barriers (biobarriers), allowing LNPs to selectively collect somewhere outside of disease-target cells again for responsive therapeutics. Most pharmaceutically important compounds were insoluble throughout water solutions, were chemical & physiologically unstable, or have toxicities. Among the most potential drug carrier for bioactive organic compounds is LBNPs (Lipid based nanoparticles) technologies. Its present use in chemotherapy have transformed treatment for cancer by increasing the antitumor effect of a number of chemotherapeutics. Because they may be created using naturally occurring sources, LBNPs have great temporal and thermal stability, maximum load potential, simplicity of preparations, cheap manufacturing costs, & big manufacturing output. Furthermore, combining chemotherapeutic drugs with LNPs reduces active therapeutic dosage and toxicities, lowers treatment resistance, & raises drug concentration in tumour cells while reducing concentrations in normal tissue. LBNPs were widely studied in cancer treatment, both in vitro and in vivo, with encouraging outcomes in certain clinical trials. This study provides an overview of the many types of LBNPs which have been created in latest years and their applications and contributions in different types of cancers.

Emerging vaccine nanotechnology: From defense against infection to sniping cancer

Looking retrospectively at the development of humanity, vaccination is an unprecedented medical landmark that saves lives by harnessing the human immune system. During the ongoing coronavirus disease 2019 (COVID-19) pandemic, vaccination is still the most effective defense modality. The successful clinical application of the lipid nanoparticle-based Pfizer/BioNTech and Moderna mRNA COVID-19 vaccines highlights promising future of nanotechnology in vaccine development. Compared with conventional vaccines, nanovaccines are supposed to have advantages in lymph node accumulation, antigen assembly, and antigen presentation; they also have, unique pathogen biomimicry properties because of well-organized combination of multiple immune factors. Beyond infectious diseases, vaccine nanotechnology also exhibits considerable potential for cancer treatment. The ultimate goal of cancer vaccines is to fully mobilize the potency of the immune system as a living therapeutic to recognize tumor antigens and eliminate tumor cells, and nanotechnologies have the requisite properties to realize this goal. In this review, we summarize the recent advances in vaccine nanotechnology from infectious disease prevention to cancer immunotherapy and highlight the different types of materials, mechanisms, administration methods, as well as future perspectives.

Intratumoral administration of STING-activating nanovaccine enhances T cell immunotherapy

BACKGROUND

Cancer vaccines are able to achieve tumor-specific immune editing in early-phase clinical trials. However, the infiltration of cytotoxic T cells into immune-deserted tumors is still a major limiting factor. An optimized vaccine approach to induce antigen-specific T cells that can perform robust tumor infiltration is important to accelerate their clinical translation. We previously developed a STING-activating PC7A nanovaccine that produces a strong anti-tumor T cell response on subcutaneous injection. This study systematically investigated the impact of administration methods on the performance of nanovaccines.

METHODS

Tumor growth inhibition by intratumoral delivery and subcutaneous delivery of nanovaccine was investigated in TC-1 human papillomavirus-induced cancer model and B16-OVA melanoma model. Nanovaccine distribution in vivo was detected by clinical camera imaging, systemic T cell activation and tumor infiltration were tested by in vivo cytotoxicity killing assay and flow cytometry. For mechanism analysis, T cell recruitment was investigated by in vivo migration blocking assay, multiplex chemokine array, flow cytometry, RT-qPCR, chemotaxis assay and gene knockout mice.

RESULTS

Nanovaccine administration was found to alter T cell production and infiltration in tumors. Intratumoral delivery of nanovaccines displayed superior antitumor effects in multiple tumor models compared with subcutaneous delivery. Mechanistic investigation revealed that intratumoral administration of the nanovaccine significantly increased the infiltration of antigen-specific T cells in TC-1 tumors, despite the lower systemic levels of T cells compared with subcutaneous injection. The inhibition of tumor growth by nanovaccines is primarily dependent on CD8⁺ cytotoxic T cells. Nanovaccine accumulation in tumors upregulates CXCL9 expression in myeloid cells in a STING dependent manner, leading to increased recruitment of IFNγ-expressing CD8⁺ T cells from the periphery, and IFNγ reciprocally stimulates CXCL9 expression in myeloid cells, resulting in positive feedback between myeloid-CXCL9 and T cell-IFNγ to promote T cell recruitment. However, the STING agonist alone could not sustain this effect in the presence of a systemic deficiency in antigen-specific T cells.

CONCLUSIONS

Our results demonstrate that intratumoral administration of PC7A nanovaccine achieved stronger antitumor immunity and efficacy over subcutaneous injection. These data suggest intratumoral administration should be included in the therapeutic design in the clinical use of nanovaccine.

Well-Defined Mannosylated Polymer for Peptide Vaccine Delivery with Enhanced Antitumor Immunity

Peptide-based cancer vaccines offer production and safety advantages but have had limited clinical success due to their intrinsic instability, rapid clearance, and low cellular uptake. Nanoparticle-based delivery vehicles can improve the in vivo stability and cellular uptake of peptide antigens. Here, a well-defined, self-assembling mannosylated polymer is developed for anticancer peptide antigen delivery. The amphiphilic polymer is prepared by reversible addition-fragmentation chain transfer (RAFT) polymerization, and the peptide antigens are conjugated to the pH-sensitive hydrophobic block through the reversible disulfide linkage for selective release after cell entry. The polymer-peptide conjugates self-assemble into sub-100 nm micelles at physiological pH and dissociate at endosomal pH. The mannosylated micellar corona increases the accumulation of vaccine cargoes in the draining inguinal lymph nodes and facilitates nanoparticle uptake by professional antigen presenting cells. In vivo studies demonstrate that the mannosylated micelle formulation improves dendritic cell activation and enhances antigen-specific T cell responses, resulting in higher antitumor immunity in tumor-bearing mice compared to free peptide antigen. The mannosylated polymer is therefore a simple and promising platform for the delivery of peptide cancer vaccines.

Advanced Biomaterials for Cell-Specific Modulation and Restore of Cancer Immunotherapy

The past decade has witnessed the explosive development of cancer immunotherapies. Nevertheless, low immunogenicity, limited specificity, poor delivery efficiency, and off-target side effects remain to be the major limitations for broad implementation of cancer immunotherapies to patient bedside. Encouragingly, advanced biomaterials offering cell-specific modulation of immunological cues bring new solutions for improving the therapeutic efficacy while relieving side effect risks. In this review, focus is given on how functional biomaterials can enable cell-specific modulation of cancer immunotherapy within the cancer-immune cycle, with particular emphasis on antigen-presenting cells (APCs), T cells, and tumor microenvironment (TME)-resident cells. By reviewing the current progress in biomaterial-based cancer immunotherapy, here the aim is to provide a better understanding of biomaterials' role in targeting modulation of antitumor immunity step-by-step and guidelines for rationally developing targeting biomaterials for more personalized cancer immunotherapy. Moreover, the current challenge and future perspective regarding the potential application and clinical translation will also be discussed.

Formulation of simvastatin within high density lipoprotein enables potent tumour radiosensitisation

Preclinical, clinical and epidemiologic studies have established the potent anticancer and radiosensitisation effects of HMG-CoA reductase inhibitors (statins). However, the low bioavailability of oral statin formulations is a key barrier to achieving effective doses within tumour. To address this issue and ascertain the radiosensitisation potential of simvastatin, we developed a parenteral high density lipoprotein nanoparticle (HDL NP) formulation of this commonly used statin. A scalable method for the preparation of the simvastatin-HDL NPs was developed using a 3D printed microfluidic mixer. This enables the production of litre scale amounts of particles with minimal batch to batch variation. Simvastatin-HDL NPs enhanced the radiobiological response in 2D/3D head and neck squamous cell carcinoma (HNSCC) in vitro models. The simvastatin-HDL NPs radiosensitisation was comparable to that of 10 and 5 times higher doses of free drug in 2D and 3D cultures, respectively, which could be partially explained by more efficient cellular uptake of the statin in the nanoformulation as well as by the inherent biological activity of the HDL NPs on the cholesterol pathway. The radiosensitising potency of the simvastatin-HDL nanoformulation was validated in an immunocompetent MOC-1 HNSCC tumour bearing mouse model. This data supports the rationale of repurposing statins through reformulation within HDL NPs. Statins are safe and readily available molecules including as generic, and their use as radiosensitisers could lead to much needed effective and affordable approaches to improve treatment of solid tumours.

Therapeutic Vaccines Targeting Neoantigens to Induce T-Cell Immunity against Cancers

Cancer immunotherapy has achieved multiple clinical benefits and has become an indispensable component of cancer treatment. Targeting tumor-specific antigens, also known as neoantigens, plays a crucial role in cancer immunotherapy. T cells of adaptive immunity that recognize neoantigens, but do not induce unwanted off-target effects, have demonstrated high efficacy and low side effects in cancer immunotherapy. Tumor neoantigens derived from accumulated genetic instability can be characterized using emerging technologies, such as high-throughput sequencing, bioinformatics, predictive algorithms, mass-spectrometry analyses, and immunogenicity validation. Neoepitopes with a higher affinity for major histocompatibility complexes can be identified and further applied to the field of cancer vaccines. Therapeutic vaccines composed of tumor lysates or cells and DNA, mRNA, or peptides of neoantigens have revoked adaptive immunity to kill cancer cells in clinical trials. Broad clinical applicability of these therapeutic cancer vaccines has emerged. In this review, we discuss recent progress in neoantigen identification and applications for cancer vaccines and the results of ongoing trials.

Triggering Immune System With Nanomaterials for Cancer Immunotherapy

Cancer is a major cause of incidence rate and mortality worldwide. In recent years, cancer immunotherapy has made great progress in the preclinical and clinical treatment of advanced malignant tumors. However, cancer patients will have transient cancer suppression reaction and serious immune related adverse reactions when receiving immunotherapy. In recent years, nanoparticle-based immunotherapy, which can accurately deliver immunogens, activate antigen presenting cells (APCs) and effector cells, provides a new insight to solve the above problems. In this review, we discuss the research progress of nanomaterials in immunotherapy including nanoparticle-based delivery systems, nanoparticle-based photothermal and photodynamic immunotherapy, nanovaccines, nanoparticle-based T cell cancer immunotherapy and nanoparticle-based bacteria cancer immunotherapy. We also put forward the current challenges and prospects of immunomodulatory therapy.

Lymph node-targeted neoantigen nanovaccines potentiate anti-tumor immune responses of post-surgical melanoma

Background

Neoantigens are considered ideal targets for immunotherapy, especially tumor vaccine, because of their strong specificity and immunogenicity. Here, we developed a neoantigen nanovaccine used liposomes with lymph-node targeting characteristic.

Methods

Our nanovaccine was composed of neoantigens, an amphiphilic liposome and an adjuvant Montanide™ ISA 51. Small animal imaging system and immunofluorescence staining were used to identify the distribution of nanovaccines. A subcutaneous-tumor-resection mouse model of melanoma was established to evaluate the anti-tumor efficacy. Flow cytometry was performed to assay the immune responses initiated by nanovaccines.

Results

Nanovaccines could traffic to lymph nodes, be uptaken by CD11c⁺ DCs and promote DCs maturity. After the treatment of our neoantigen nanovaccines, the average recurrence time was extended from 11 to 16 days and the median survival time was even prolonged 7.5 days relative to the control group (NS group). Nanovaccines increased neoantigen-specific T cells to 10-fold of free vaccines, and upregulated Th1 cytokines, such as IFN-γ and TNF-α. The anti-tumor activity of spleen lymphocytes in the nanovaccine group was significantly stronger than that of other groups. However, some immune-inhibitory cells or molecules in tumor microenvironment have been detected upregulated under the immune pressure of neoantigen nanovaccines, such as Tregs and PD-L1. The efficacy of the neoantigen nanovaccine combined with anti-PD1 antibody or Treg inhibiting peptide P60 was better than that of the single treatment.

Conclusions

We developed a general vaccine strategy, triggering specific T cell responses, and provided feasible combination strategies for better anti-tumor efficacy.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s12951-022-01397-7.

Immune evader cancer stem cells direct the perspective approaches to cancer immunotherapy

Exploration of tumor immunity leads to the development of immune checkpoint inhibitors and cell-based immunotherapies which improve the clinical outcomes in several tumor types. However, the poor clinical efficacy of these treatments observed for other tumors could be attributed to the inherent complex tumor microenvironment (TME), cellular heterogeneity, and stemness driven by cancer stem cells (CSCs). CSC-specific characteristics provide the bulk tumor surveillance and resistance to entire eradication upon conventional therapies. CSCs-immune cells crosstalk creates an immunosuppressive TME that reshapes the stemness in tumor cells, resulting in tumor formation and progression. Thus, identifying the immunological features of CSCs could introduce the therapeutic targets with powerful antitumor responses. In this review, we summarized the role of immune cells providing CSCs to evade tumor immunity, and then discussed the intrinsic mechanisms represented by CSCs to promote tumors' resistance to immunotherapies. Then, we outlined potent immunotherapeutic interventions followed by a perspective outlook on the use of nanomedicine-based drug delivery systems for controlled modulation of the immune system.

Fabrication of subunit nanovaccines by physical interaction

Vaccines can improve the quality of human life by preventing the burden of infectious diseases. Also, vaccination is becoming a powerful medication for preventing and treating tumors. Various vaccines have been developed based on the origin of the antigens. Herein, we focus on the subunit vaccines whose antigens are proteins or peptides. The advantage of subunit vaccines is safety for recipients; however, the immunogenicity of subunit antigens is relatively low. Nanoparticular delivery systems have been applied to improve the immunocompetence of subunit vaccines by targeting lymph nodes, and effectively present antigens to immune cells. Moreover, adding appropriate molecular adjuvants may strengthen the antigens to elicit immune response. In this perspective article, we first elucidate the characteristics of immunity induced by subunit nanovaccines and then summarize the strategies to fabricate subunit nanovaccines with delivering materials. Herein we highlight non-covalent interaction to fabricate nanoparticular subunit vaccines.

Bacteria as Nanoparticle Carriers for Immunotherapy in Oncology

The use of nanocarriers to deliver antitumor agents to solid tumors must overcome biological barriers in order to provide effective clinical responses. Once within the tumor, a nanocarrier should navigate into a dense extracellular matrix, overcoming intratumoral pressure to push it out of the diseased tissue. In recent years, a paradigm change has been proposed, shifting the target of nanomedicine from the tumoral cells to the immune system, in order to exploit the natural ability of this system to capture and interact with nanometric moieties. Thus, nanocarriers have been engineered to interact with immune cells, with the aim of triggering specific antitumor responses. The use of bacteria as nanoparticle carriers has been proposed as a valuable strategy to improve both the accumulation of nanomedicines in solid tumors and their penetration into the malignancy. These microorganisms are capable of propelling themselves into biological environments and navigating through the tumor, guided by the presence of specific molecules secreted by the diseased tissue. These capacities, in addition to the natural immunogenic nature of bacteria, can be exploited to design more effective immunotherapies that yield potent synergistic effects to induce efficient and selective immune responses that lead to the complete eradication of the tumor.

Nanodisc-Mediated Conversion of Virustatic Antiviral Antibody to Disrupt Virus Envelope in Infected Cells

Many antibody-based antivirals, including broadly neutralizing antibodies (bnAbs) against various influenza virus strains, suffer from limited potency. A booster of the antiviral activity of an antibody is expected to facilitate development of antiviral therapeutics. In this study, a nanodisc (ND), a discoidal lipid bilayer encircled by membrane scaffold proteins, is engineered to provide virucidal properties to antibodies, thereby augmenting their antiviral activity. NDs carrying the Fc-binding peptide sequence form an antibody-ND complex (ANC), which can co-endocytose into cells infected with influenza virus. ANC efficiently inhibits endosome escape of viral RNA by dual complimentary mode of action. While the antibody moiety in an ANC inhibits hemagglutinin-mediated membrane fusion, its ND moiety destroys the viral envelope using free hemagglutinins that are not captured by antibodies. Providing virus-infected host cells with the ability to self-eliminate by the synergistic effect of ANC components dramatically amplifies the antiviral efficacy of a bnAb against influenza virus. When the efficacy of ANC is assessed in mouse models, administration of ANCs dramatically reduces morbidity and mortality compared to bnAb alone. This study is the first to demonstrate the novel nanoparticle ANC and its role in combating viral infections, suggesting that ANC is a versatile platform applicable to various viruses.

GSH-Responsive Metal-Organic Framework for Intratumoral Release of NO and IDO Inhibitor to Enhance Antitumor Immunotherapy

Immunotherapy brings great benefits for tumor therapy in clinical treatments but encounters the severe challenge of low response rate mainly because of the immunosuppressive tumor microenvironment. Multifunctional nanoplatforms integrating effective drug delivery and medical imaging offer tremendous potential for cancer treatment, which may play a critical role in combinational immunotherapy to overcome the immunosuppressive microenvironment for efficient tumor therapy. Here, a nanodrug (BMS-SNAP-MOF) is prepared using glutathione (GSH)-sensitive metal-organic framework (MOF) to encapsulate an immunosuppressive enzyme indoleamine 2,3-dioxygenase (IDO) inhibitor BMS-986205, and the nitric oxide (NO) donor s-nitrosothiol groups. The high T1 relaxivity allows magnetic resonance imaging to monitor nanodrug distribution in vivo. After the nanodrug accumulation in tumor tissue via the EPR effect and subsequent internalization into tumor cells, the enriched GSH therein triggers cascade reactions with MOF, which disassembles the nanodrug to rapidly release the IDO-inhibitory BMS-986205 and produces abundant NO. Consequently, the IDO inhibitor and NO synergistically modulate the immunosuppressive tumor microenvironment with increase CD8⁺ T cells and reduce Treg cells to result in highly effective immunotherapy. In an animal study, treatment using this theranostic nanodrug achieves obvious regressions of both primary and distant 4T1 tumors, highlighting its application potential in advanced tumor immunotherapy.

Mannan-decorated pathogen-like polymeric nanoparticles as nanovaccine carriers for eliciting superior anticancer immunity

Using nanotechnology for cancer vaccine design holds great promise because of the intrinsic feature of nanoparticles in being captured by antigen-presenting cells (APCs). However, there are still obstacles in current nanovaccine systems in achieving efficient tumor therapeutic effects, which could partially be attributed to the unsatisfactory vaccine carrier design. Herein, we report a mannan-decorated pathogen-like polymeric nanoparticle as a protein vaccine carrier for eliciting robust anticancer immunity. This nanovaccine was constructed as a core-shell structure with mannan as the shell, polylactic acid-polyethylenimine (PLA-PEI) assembled nanoparticle as the core, and protein antigens and Toll-like receptor 9 (TLR9) agonist CpG absorbed onto the PLA-PEI core via electrostatic interactions. Compared to other hydrophilic materials, mannan decoration could greatly enhance the lymph node draining ability of the nanovaccine and promote the capturing by the CD8⁺ dendritic cells (DCs) in the lymph node, while PLA-PEI as the inner core could enhance antigen endosome escape thus promoting the antigen cross-presentation. In addition, mannan itself as a TLR4 agonist could synergize with CpG for maximally activating the DCs. Excitingly, we observed in several murine tumor models that using this nanovaccine alone could elicit robust immune response in vivo and result in superior anti-tumor effects with 50% of mice completely cured. This study strongly evidenced that mannan decoration and a rationally designed nanovaccine system could be quite robust in tumor vaccine therapy.

Antigen epitope-TLR7/8a conjugate as self-assembled carrier-free nanovaccine for personalized immunotherapy

Epitope-based vaccine is a promising personalized cancer immunotherapy; however, a simple and effective approach for its bulk manufacturing is challenging. Current vaccination strategies complicate the process by introducing unnecessary components such as additional delivery carriers, and assembly units. Herein, a type of toll-like receptor 7/8 agonist-epitope conjugate (termed as TLR7/8a-epitope) has been developed as a self-assembled and carrier-free nano vaccine platform, which effectively introduces the antigen and adjuvant with maximum precision, resulting in significantly enhanced dendritic cells (DCs) activation through the MyD88-dependent TLR signaling pathway. TLR7/8a-epitope nanovaccine can prolong the local retention and increase drainage efficiency into the lymph node, eliciting a significantly higher level of CD8 T-cell immunity than those of conventional vaccine formulations. The immunization with TLR7/8a-epitope nanovaccine in mice can not only resist the invasion of B16 cancer cells, but also produce significant therapeutic effects against established B16 melanoma tumors. Therefore, the TLR7/8a-epitope nanovaccine, developed by the direct chemical conjugation of antigen peptide with immunoadjuvant, has great advantages of clear and leanest compositions, controllable and definite preparation process, and remarkable therapeutic effects, representing a new appraoch for personalized cancer immunotherapy. STATEMENT OF SIGNIFICANCE: Herein, a kind of toll-like receptor 7/8 agonist-epitope conjugate was developed and spontaneously self-assemble into nanostructure in aqueous solution without the use of any additional constituents, which can be termed as unique carrier-free nanovaccine platform, providing effectually the leanest vaccine components with maximally and precisely loading of antigen and adjuvant. Significantly, the nanovaccine augmented the immunogenicity of antigenic peptide by increasing DCs activation through MyD88-mediated TLR signaling pathways and promoting T-cell priming. Moreover, nanovaccines could prolong the local retention and further increase the efficiency of drainage into dLNs, which was contributing to efficient initiation of epitope-specific memory and effector T-cell immune responses, leading to effective prophylactic and therapeutic antitumor effects.

Synthetic polymer material modified by d-peptide and its targeted application in the treatment of non-small cell lung cancer

Liposomes functionalized with targeted material offer a breakthrough compared with passive drug delivery. Here, we designed a polymer material, VAP-PEG₃₃₅₀-DSPE (VAP-PEG-DSPE), modified with a d-peptide VAP ligand that combines tumor-homing VAP with GRP78 receptor, a cancer marker on the membranes of many cancer cells. This paper establishes a docetaxel-loaded lipid nanodisk modified with multifunctional material to evaluate its anti-NSCLC efficacy in vivo. Additionally, the present study verified that VAP-conjugated nanodisks adapt to the developed tumor vasculature of the lung cancer microenvironment, making it a promising nanocarrier for NSCLC-targeting therapy. Moreover, in vitro and in vivo experiments demonstrated the targeting ability of VAP-DISK/DTX to tumor cells. Lung slices of mice also demonstrated the safety of VAP-DISK/DTX. The encapsulation efficiency of docetaxel-disks (VAP-DISK/DTX) was as high as 92.46±4.48%. Encapsulating anti-cancer drugs in lipid nanoparticles is thus an effective mechanism to change the pharmacokinetic and pharmacodynamic characteristics of drugs.

A Minimalist Binary Vaccine Carrier for Personalized Postoperative Cancer Vaccine Therapy

In recent years, significant evolutions have been made in applying nanotechnologies for prophylactic and therapeutic cancer vaccine design. However, the clinical translation of nanovaccines is still limited owing to their complicated compositions and difficulties in the spatiotemporal coordination of antigen-presenting cell activation and antigen cross-presentation. Herein, a minimalist binary nanovaccine (BiVax) is designed that integrates innate stimulating activity into the carrier to elicit robust antitumor immunity. The authors started by making a series of azole molecules end-capped polyethylenimine (PEI-M), and were surprised to find that over 60% of the PEI-M polymers have innate stimulating activity via activation of the stimulator of interferon genes pathway. PEI-4BImi, a PEI-M obtained from a series of polymers, elicits robust antitumor immune responses when used as a subcutaneously injected nanovaccine by simply mixing with ovalbumin antigens, and this BiVax system performs much better than the traditional ternary vaccine system, as well as, commercialized aluminum-containing adjuvants. This system also enables the fast preparation of personalized BiVax by compositing PEI-4BImi with autologous tumor cell membrane protein antigens, and a 60% postoperative cure rate is observed when combined with immune checkpoint inhibitors.

Peptidic microarchitecture-trapped tumor vaccine combined with immune checkpoint inhibitor or PI3Kγ inhibitor can enhance immunogenicity and eradicate tumors

Background

With the rapid development of immune checkpoint inhibitors and neoantigen (NeoV)-based personalized tumor vaccines, tumor immunotherapy has shown promising therapeutic results. However, the limited efficacy of available tumor vaccines impedes the development of personalized tumor immunotherapy. In this study, we developed a novel tumor vaccine system and proposed combined therapeutic strategies for improving treatment effects.

Methods

We developed a novel tumor vaccine system comprising a newly synthesized peptidic microarchitecture (PMA) with high assembly efficacy. The PMA-trapped neoantigen vaccine was developed to codeliver tumor neoantigen and the Toll-like receptor 9 agonist CpG (NeoV), abbreviated as PMA-NeoV. A microfluidic chip was used to produce PMA particles in a uniform and precise manner. Vaccine effectiveness was investigated both in vitro and in vivo. The combined immunotherapeutic effect of PMA-NeoV with anti-programmed cell death ligand 1 antibody (aPD-L1) or with the phosphatidylinositol 3‑kinase γ (PI3Kγ) inhibitor IPI-549 was further tested in MC38 mouse tumor model.

Results

PMA-NeoV not only promoted codelivery of the tumor vaccine but also potentiated vaccine immunogenicity. Moreover, compared with free NeoV, PMA-NeoV significantly increased the number of tumor-infiltrating lymphocytes, promoted the neoantigen-specific systemic immune response, and suppressed murine colon MC38 tumor growth. Furthermore, PMA-NeoV increased the expression of programmed cell death receptor-1 on T lymphocytes, and in combination with aPD-L1 eradicated seven of eight MC38 tumors by rescuing exhausted T lymphocytes. Moreover, we combined the PMA-NeoV with the IPI-549, a molecular switch that controls immune suppression, and found that this combination significantly suppressed tumor growth and eradicated five of eight inoculated tumors, by switching suppressive macrophages to their active state and activating T cells to prime a robust tumor immune microenvironment.

Conclusions

We developed a tumor vaccine delivery system and presented a promising personalized tumor vaccine-based therapeutic regimen in which a tumor vaccine delivery system is combined with an aPD-L1 or PI3Kγ inhibitor to improve tumor immunotherapy outcomes.

Identification of Neoantigens in Cancer Cells as Targets for Immunotherapy

The clinical benefits of immune checkpoint blockage (ICB) therapy have been widely reported. In patients with cancer, researchers have demonstrated the clinical potential of antitumor cytotoxic T cells that can be reinvigorated or enhanced by ICB. Compared to self-antigens, neoantigens derived from tumor somatic mutations are believed to be ideal immune targets in tumors. Candidate tumor neoantigens can be identified through immunogenomic or immunopeptidomic approaches. Identification of neoantigens has revealed several points of the clinical relevance. For instance, tumor mutation burden (TMB) may be an indicator of immunotherapy. In various cancers, mutation rates accompanying neoantigen loads may be indicative of immunotherapy. Furthermore, mismatch repair-deficient tumors can be eradicated by T cells in ICB treatment. Hence, immunotherapies using vaccines or adoptive T-cell transfer targeting neoantigens are potential innovative strategies. However, significant efforts are required to identify the optimal epitopes. In this review, we summarize the recent progress in the identification of neoantigens and discussed preclinical and clinical studies based on neoantigens. We also discuss the issues remaining to be addressed before clinical applications of these new therapeutic strategies can be materialized.

Case Report: Pathological Complete Response in a Lung Metastasis of Phyllodes Tumor Patient Following Treatment Containing Peptide Neoantigen Nano-Vaccine

Some of the mutant peptides produced by gene mutation transcription and translation have the ability to induce specific T cells, which are called new antigens. Neoantigen-based peptide, DNA, RNA, and dendritic cell vaccines have been used in the clinic. In this paper, we describe a lung metastasis of a phyllodes tumor patient demonstrating pathological complete response following treatment containing personalized multi-epitope peptide neoantigen nano-vaccine. Based on whole-exome sequencing (WES), RNA sequencing, and new antigen prediction, several mutated peptide fragments were predicted to bind to the patient’s human leukocyte antigen (HLA) allotypes, including ten peptides with high predicted binding affinity for six genes. The pulmonary metastases remained stable after the four cycles of anti-PD1 and anlotinib. After the addition of the multi-epitope peptide neoantigen nano-vaccine, the tumor began to collapse and contracture developed, accompanied by a decrease of tumor markers to normal, and complete pathological remission was achieved. With the use of the vaccination, recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) was used every time, and low-dose cyclophosphamide was injected every 3 weeks to improve efficacy. Peripheral blood immune monitoring demonstrated immune reactivity against a series of peptides, with the most robust post-vaccine T-cell response detected against the HLA-DRB1*0901-restricted SLC44A5 V54F peptide.

An in Silico Approach to Reveal the Nanodisc Formulation of Doxorubicin

Molecular dynamic behaviors of nanodisc (ND) formulations of free doxorubicin (DOX) and DOX conjugated lipid prodrug molecules were investigated by molecular dynamics (MD) simulations. We have unveiled how formulation design affects the drug release profile and conformational stability of ND assemblies. Our simulation results indicate that free DOX molecules loaded in the ND system experienced rapid dissociation due to the unfavorable orientation of DOX attached to the lipid surface. It is found that DOX tends to form aggregates with higher drug quantities. In contrast, lipidated DOX-prodrugs incorporated in ND formulations exhibited sufficient ND conformational stability. The drug loading capacity is dependent on the type of lipid molecules grafted on the DOX-prodrug, and the drug loading quantities in a fixed area of NDs follow the order: DOX-BMPH-MP > DOX-BMPH-TC > DOX-BMPH-PTE. To gain further insight into the dynamic characteristics of ND formulations governed by different kinds of lipidation, we investigated the conformational variation of ND components, intermolecular interactions, the solvent accessible surface area, and individual MSP1 residue flexibility. We found that the global conformational stability of DOX-prodrug-loaded ND assemblies is influenced by the molecular flexibility and lipidated forms of DOX-prodrug. We also found that the spontaneous self-aggregation of DOX-prodrugs with increasing quantities on ND could reduce the membrane fluidity and enhance the conformational stability of ND formulations.

Recent Advance of Nanomaterial-Mediated Tumor Therapies in the Past Five Years

Cancer has posed a major threat to human life and health with a rapidly increasing number of patients. The complexity and refractory of tumors have brought great challenges to tumor treatment. In recent years, nanomaterials and nanotechnology have attracted more attention and greatly improved the efficiency of tumor therapies and significantly prolonged the survival period, whether for traditional tumor treatment methods such as radiotherapy, or emerging methods, such as phototherapy and immunotherapy, sonodynamic therapy, chemodynamic therapy and RNA interference therapeutics. Various monotherapies have obtained positive results, while combination therapies are further proposed to prevent incomplete eradication and recurrence of tumors, strengthen tumor killing efficacy with minimal side effects. In view of the complementary promotion effects between different therapies, it is vital to utilize nanomaterials as the link between monotherapies to achieve synergistic performance. Further development of nanomaterials with efficient tumor-killing effect and better biosafety is more in line with the needs of clinical treatment. In a word, the development of nanomaterials provides a promising way for tumor treatment, and here we will review the emerging nanomaterials towards radiotherapy, phototherapy and immunotherapy, and summarized the developed nanocarriers applied for the tumor combination therapies in the past 5 years, besides, the advances of some other novel therapies such as sonodynamic therapy, chemodynamic therapy, and RNA interference therapeutics have also been mentioned.

Gene Regulation Using Nanodiscs Modified with HIF-1-α Antisense Oligonucleotides

Delivery of nucleic acids can be hindered by multiple factors including nuclease susceptibility, endosome trapping, and clearance. Multiple nanotechnology scaffolds have offered promising solutions, and among these, lipid-based systems are advantageous because of their high biocompatibility and low toxicity. However, many lipid nanoparticle systems still have issues regarding stability, rapid clearance, and cargo leakage. Herein, we demonstrate the use of a synthetic nanodisc (ND) scaffold functionalized with an anti-HIF-1-α antisense oligonucleotide (ASO) to reduce HIF-1-α mRNA transcript levels. We prepared ND conjugates by using a mixture of phosphoglycerolipids with phosphocholine and phosphothioethanol headgroups that self-assemble into a ∼13 × 5 nm discoidal structure upon addition of a 22-amino-acid ApoA1 mimetic peptide. Optimized reaction conditions yield 15 copies of the anti-HIF-1-α ASO DNA covalently conjugated to the thiolated phospholipids using maleimide-thiol chemistry. We show that DNA-ND conjugates are active, nuclease resistant, and rapidly internalized into cells to regulate HIF-1-α mRNA levels without the use of transfection agents. DNA-ND uptake is partially mediated through Scavenger Receptor B1 and the ND conjugates show enhanced knockdown of HIF-1-α compared to that of the soluble ASOs in multiple cell lines. Our results demonstrate that covalently functionalized NDs may offer an improved platform for ASO therapeutics.