Macromolecule nanotherapeutics: approaches and challenges

Long-Circulating Lipid Nanospheres Loaded with Flurbiprofen Axetil for Targeted Rheumatoid Arthritis Treatment

Background

Flurbiprofen axetil (FA) is a non-steroidal anti-inflammatory drug with good analgesic and anti-inflammatory effects. However, it suffers from poor solubility, short circulation time, and off-target binding profile, which significantly limit its clinical application. Here, we loaded FA into stealth lipid microspheres modified with the arginine-glycine-aspartic acid (RGD) peptide (cRGD-FA-SLM), and examined the therapeutic potential of the resulting platform for the treatment of rheumatoid arthritis (RA).

Methods

cRGD-FA-SLM was prepared by high pressure homogenization, and its toxicity and uptake by macrophages were examined using cultures of RAW264.7 cells. Hemolysis and hepatotoxicity tests were performed to assess the safety of the developed platform, while its pharmacokinetics, biodistribution, and therapeutic efficacy were investigated in a collagen-induced arthritis rat model.

Results

cRGD-FA-SLM showed homogeneous spherical morphology and efficient encapsulation of FA. The developed platform was non-toxic to normal macrophages and was selectively internalized by lipopolysaccharide-activated macrophages in vitro, while it distributed mainly to arthritic joints and significantly prolonged FA in circulation in vivo. cRGD-FA-SLM also significantly reduced the expression of prostaglandin E2 and alleviated joint edema and bone erosion, showing prolonged analgesic effects in arthritic rats.

Conclusion

cRGD-FA-SLM shows good inflammation-targeting ability and prolongs drug circulation in vivo, suggesting promise as an anti-inflammatory and analgesic agent for targeted RA treatment.

Nanomedicines: intervention in inflammatory pathways of cancer

Inflammation is a complex defense process that maintains tissue homeostasis. However, this complex cascade, if lasts long, may contribute to pathogenesis of several diseases. Chronic inflammation has been exhaustively studied in the last few decades, for its contribution in development and progression of cancer. The intrinsic limitations of conventional anti-inflammatory and anti-cancer therapies triggered the development of nanomedicines for more effective and safer therapies. Targeting inflammation and tumor cells by nanoparticles, encapsulated with active therapeutic agents, offers a promising outcome with patient survival. Considerable technological success has been achieved in this field through exploitation of tumor microenvironment, and recognition of molecules overexpressed on endothelial cells or macrophages, through enhanced vascular permeability, or by rendering biomimetic approach to nanoparticles. This review focusses on the inflammatory pathways in progression of a tumor, and advancement in nanotechnologies targeting these pathways. We also aim to identify the gaps that hinder the successful clinical translation of nanotherapeutics with further clinical studies that will allow oncologist to precisely identify the patients who may be benefited from nanotherapy at time when promotion or progression of tumor initiates. It is postulated that the nanomedicines, in near future, will shift the paradigm of cancer treatment and improve patient survival.

Carrier gas triggered controlled biolistic delivery of DNA and protein therapeutics from metal-organic frameworks

The efficacy and specificity of protein, DNA, and RNA-based drugs make them popular in the clinic; however, these drugs are often delivered via injection, requiring skilled medical personnel, and producing biohazardous waste. Here, we report an approach that allows for their controlled delivery, affording either a burst or slow release without altering the formulation. We show that when encapsulated within zeolitic-imidazolate framework eight (ZIF-8), the biomolecules are stable in powder formulations and can be inoculated with a low-cost, gas-powered "MOF-Jet" into living animal and plant tissues. Additionally, their release profiles can be modulated through judicious selection of the carrier gas used in the MOF-Jet. Our in vitro and in vivo studies reveal that when CO₂ is used, it creates a transient and weakly acidic local environment that causes a near-instantaneous release of the biomolecules through an immediate dissolution of ZIF-8. Conversely, when air is used, ZIF-8 biodegrades slowly, releasing the biomolecules over a week. This is the first example of controlled-biolistic delivery of biomolecules using ZIF-8, which provides a powerful tool for fundamental and applied science research.

Extracellular vesicle-based macromolecule delivery systems in cancer immunotherapy

Great attention has been paid to the impressive role the macromolecules played in cancer immunotherapy, however, the applications were largely limited by their poor circulation stability, low cellular uptake efficiency, and off-target effects. As an important messenger of intercellular communication, extracellular vesicles (EVs) exhibit unique advantages in macromolecule delivery compared to traditional synthetic carriers, offering new possibilities for modern drug delivery. These naturally derived carriers can achieve stable, efficient, and selective delivery of macromolecules and improve the efficacy and potentiality of macromolecular drugs in cancer immunotherapy. This review provides a brief overview of the unique features of EVs related to macromolecule delivery, the strategies and recent advances of using EVs as macromolecule delivery carriers in cancer immunotherapy.

Enhancing the Cellular Uptake of Macromolecules via Enzyme-Instructed Self-Assembly

Poor solubility, low cellular uptake, and poor cell selectivity are the main obstacles hampering the therapeutic potential and clinic application of macromolecules. To overcome these limitations, here we propose a chemical modification strategy of macromolecules based on enzyme-instructed self-assembly (EISA). By using protoporphyrin IX (PpIX) and its metal complex Zn-PpIX as the modification objects, we demonstrated that the integration of enzymatic transformation and molecular self-assembly of macromolecules successfully improved the solubility of macromolecules, enhancing their intracellular uptake selectively against cancer cells. The proposed strategy is potentially applicable as a general tool for the development of macromolecule-based nanomedicine.

Gap Junction-Mediated Delivery of Polymeric Macromolecules

Cellular delivery of therapeutic macromolecules such as proteins, peptides, and nucleic acids remains limited due to inefficient transport across the cellular plasma membrane. Gap junction channels, composed of connexin proteins, provide a mechanism for direct transfer of small molecules across membranes, and recent evidence suggests that the transfer of larger, polymer-like molecules such as microRNAs may be possible. Here, we report direct evidence of gap junction-mediated transfer of polymeric macromolecules. Specifically, we examined the transport of dextran chains with molecular weights ranging from 10 to 70 kDa. We found that dextran chains of up to 40 kDa can diffuse through at least five cell layers in a gap junction-dependent manner within a 30 min time frame. Further, we evaluated the ability of connectosomes, cell-derived vesicles containing functional connexin proteins, to be loaded with dextran chains. By opening connexon hemichannel pores within the membranes of connectosomes, we found that 10 kDa dextran was loaded into more than 90% of vesicles, with reduced levels of loading for dextran chains of larger molecular weight. Upon delivering 10 kDa dextran-loaded connectosomes to cells, we further found that connectosomes transferred these membrane-impermeable molecules to the cellular cytosol with dramatically improved efficiency in comparison to the delivery of free, unencapsulated dextran. Collectively, these results reveal that polymeric macromolecules can be delivered to cells via gap junctions, suggesting that the gap junction route may be useful for the delivery of polymeric therapeutic molecules, such as nucleic acids and peptides.

Biopolymer-based Carriers for DNA Vaccine Design

Over the last 30 years, genetically engineered DNA has been tested as novel vaccination strategy against various diseases, including human immunodeficiency virus (HIV), hepatitis B, several parasites, and cancers. However, the clinical breakthrough of the technique is confined by the low transfection efficacy and immunogenicity of the employed vaccines. Therefore, carrier materials were designed to prevent the rapid degradation and systemic clearance of DNA in the body. In this context, biopolymers are a particularly promising DNA vaccine carrier platform due to their beneficial biochemical and physical characteristics, including biocompatibility, stability, and low toxicity. This article reviews the applications, fabrication, and modification of biopolymers as carrier medium for genetic vaccines.

Preclinical models and technologies to advance nanovaccine development

The remarkable success of targeted immunotherapies is revolutionizing cancer treatment. However, tumor heterogeneity and low immunogenicity, in addition to several tumor-associated immunosuppression mechanisms are among the major factors that have precluded the success of cancer vaccines as targeted cancer immunotherapies. The exciting outcomes obtained in patients upon the injection of tumor-specific antigens and adjuvants intratumorally, reinvigorated interest in the use of nanotechnology to foster the delivery of vaccines to address cancer unmet needs. Thus, bridging nano-based vaccine platform development and predicted clinical outcomes the selection of the proper preclinical model will be fundamental. Preclinical models have revealed promising outcomes for cancer vaccines. However, only few cases were associated with clinical responses. This review addresses the major challenges related to the translation of cancer nano-based vaccines to the clinic, discussing the requirements for ex vivo and in vivo models of cancer to ensure the translation of preclinical success to patients.

Nanotheranostics through Mitochondria-targeted Delivery with Fluorescent Peptidomimetic Nanohybrids for Apoptosis Induction of Brain Cancer Cells

Overview: Malignant brain tumors remain one of the greatest challenges faced by health professionals and scientists among the utmost lethal forms of cancer. Nanotheranostics can play a pivotal role in developing revolutionary nanoarchitectures with multifunctional and multimodal capabilities to fight cancer. Mitochondria are vital organelles to eukaryotic cells, which have been recognized as a significant target in cancer therapy where, by damaging the mitochondria, it will cause irreparable cell death or apoptosis. Methods: We designed and produced novel hybrid nanostructures comprising a fluorescent semiconductor core (AgInS2, AIS) and cysteine-modified carboxymethylcellulose (termed thiomer, CMC_Cys) conjugated with mitochondria-targeting peptides (KLA) forming a macromolecular shell for combining bioimaging and for inducing brain cancer cell (U-87 MG) death. Results: The optical and physicochemical properties of the nanoconjugates demonstrated suitability as photoluminescent nanostructures for cell bioimaging and intracellular tracking. Additionally, the results proved a remarkable killing activity towards glioblastoma cells of cysteine-bearing CMC conjugates coupled with KLA peptides through the half-maximal effective concentration values, approximately 70-fold higher compared to the conjugate analogs without Cys residues. Moreover, these thiomer-based pro-apoptotic drug nanoconjugates displayed higher lethality against U-87 MG cancer cells than doxorubicin, a model drug in chemotherapy, although extremely toxic. Remarkably, these peptidomimetic nanohybrids demonstrated a relative "protective effect" regarding healthy cells while maintaining high killing activity towards malignant brain cells. Conclusion: These findings pave the way for developing hybrid nanoarchitectures applied as targeted multifunctional platforms for simultaneous imaging and therapy against cancer while minimizing the high systemic toxicity and side-effects of conventional drugs in anticancer chemotherapy.

Delivery strategies for macromolecular drugs in cancer therapy

With the development of biotherapy, biomacromolecular drugs have gained tremendous attention recently, especially in drug development field due to the sophisticated functions in vivo. Over the past few years, a motley variety of drug delivery strategies have been developed for biomacromolecular drugs to overcome the difficulties in the druggability, e.g., the instability and easily restricted by physiologic barriers. The application of novel delivery systems to deliver biomacromolecular drugs can usually prolong the half-life, increase the bioavailability, or improve patient compliance, which greatly improves the efficacy and potentiality for clinical use of biomacromolecular drugs. In this review, recent studies regarding the drug delivery strategies for macromolecular drugs in cancer therapy are summarized, mainly drawing on the development over the last five years.

Fabrication of Poly(ethylene glycol) Capsules via Emulsion Templating Method for Targeted Drug Delivery

To reduce nonspecific interactions and circumvent biological barriers, low-fouling material of poly(ethylene glycol) (PEG) is most used for the modification of drug nanocarriers. Herein, we report the fabrication of PEG capsules via the free-radical polymerization of linear PEG or 8-arm-PEG using an emulsion templating method for targeted drug delivery. Doxorubicin (DOX) could be loaded in capsules via electrostatic interactions. The obtained capsules composed of 8-arm-PEG result in a lower cell association (2.2%) compared to those composed of linear PEG (7.3%) and, therefore, demonstrate the stealth property. The functionalization of cyclic peptides containing Arg-Gly-Asp (cRGD) on PEG capsules induce high cell targeting to U87 MG cells. A cell cytotoxicity assay demonstrates the biocompatibility of PEG capsules and high drug delivery efficacy of the targeted capsules. The reported capsules with the stealth and targeting property provide a potential platform for improved drug delivery.

Bioanalysis of Targeted Nanoparticles in Monkey Plasma via LC-MS/MS

This work represents the first reporting of a comprehensive bioanalytical GLP methodology detailing the mass spectrometric quantitation of PF-05212384 dosed as a targeted polymeric encapsulated nanoparticle (PF-07034663) to monkeys. Polymeric nanoparticles are a type of drug formulation that enables the sustained release of an active therapeutic agent (payload) for targeted delivery to specific sites of action such as cancer cells. Through the careful design and engineering of the nanoparticle formulation, it is possible to improve the biodistribution and safety of a given therapeutic payload in circulation. However, the bioanalysis of nanoparticles is challenging due to the complexity of the nanoparticle drug formulation itself and the number of pharmacokinetic end points needed to characterize the in vivo exposure of the nanoparticles. Gedatolisib, also known as PF-05212384, was reformulated as an encapsulated targeted polymeric nanoparticle. The bioanalytical assays were validated to quantitate both total and released PF-05212384 derived from the encapsulated nanoparticle (PF-07034663). Assay performance calculated from quality control samples in three batch runs demonstrated intraday precision and accuracy within 10.3 and 12.2%, respectively, and interday precision and accuracy within 9.1 and 8.5%, respectively. This method leveraged automation to ease the burden of a laborious and complicated sample pretreatment and extraction procedure. The automated method was used to support a preclinical safety study in monkeys in which both released and total PF-05212384 concentrations were determined in over 1600 monkey plasma study samples via LC-MS/MS.

Engineering patient-specific cancer immunotherapies

Research into the immunological processes implicated in cancer has yielded a basis for the range of immunotherapies that are now considered the fourth pillar of cancer treatment (alongside surgery, radiotherapy and chemotherapy). For some aggressive cancers, such as advanced non-small-cell lung carcinoma, combination immunotherapies have resulted in unprecedented treatment efficacy for responding patients, and have become frontline therapies. Individualized immunotherapy, enabled by the identification of patient-specific mutations, neoantigens and biomarkers, and facilitated by advances in genomics and proteomics, promises to broaden the responder patient population. In this Perspective, we give an overview of immunotherapies leveraging engineering approaches, including the design of biomaterials, delivery strategies and nanotechnology solutions, for the realization of individualized cancer treatments such as nanoparticle vaccines customized with neoantigens, cell therapies based on patient-derived dendritic cells and T cells, and combinations of theranostic strategies. Developments in precision cancer immunotherapy will increasingly rely on the adoption of engineering principles.

Immunomodulatory Nanosystems

Immunotherapy has emerged as an effective strategy for the prevention and treatment of a variety of diseases, including cancer, infectious diseases, inflammatory diseases, and autoimmune diseases. Immunomodulatory nanosystems can readily improve the therapeutic effects and simultaneously overcome many obstacles facing the treatment method, such as inadequate immune stimulation, off-target side effects, and bioactivity loss of immune agents during circulation. In recent years, researchers have continuously developed nanomaterials with new structures, properties, and functions. This Review provides the most recent advances of nanotechnology for immunostimulation and immunosuppression. In cancer immunotherapy, nanosystems play an essential role in immune cell activation and tumor microenvironment modulation, as well as combination with other antitumor approaches. In infectious diseases, many encouraging outcomes from using nanomaterial vaccines against viral and bacterial infections have been reported. In addition, nanoparticles also potentiate the effects of immunosuppressive immune cells for the treatment of inflammatory and autoimmune diseases. Finally, the challenges and prospects of applying nanotechnology to modulate immunotherapy are discussed.

Nanoparticles for hematologic diseases detection and treatment

Nanotechnology, as an interdisciplinary science, combines engineering, physics, material sciences, and chemistry with the biomedicine knowhow, trying the management of a wide range of diseases. Nanoparticle-based devices holding tumor imaging, targeting and therapy capabilities are formerly under study. Since conventional hematological therapies are sometimes defined by reduced selectivity, low therapeutic efficacy and many side effects, in this review we discuss the potential advantages of the NPs' use in alternative/combined strategies. In the introduction the basic notion of nanomedicine and nanoparticles' classification are described, while in the main text nanodiagnostics, nanotherapeutics and theranostics solutions coming out from the use of a wide-ranging NPs availability are listed and discussed.

The role of nanoparticles in the improvement of systemic anticancer drug delivery

The systemic delivery of drugs to the body via circulation after oral administration is a preferred method of drug administration during cancer treatment given its ease of implementation. However, the physicochemical properties of many current anticancer drugs limit their effectiveness when delivered by systemic routes. The use of nanoparticles (NPs) has emerged as an effective means of overcoming the inherent limitations of systemic drug delivery. We provide herein an overview of various NP formulations that facilitate improvements in the efficacy of various anticancer drugs compared with the free drug. This review will be useful to the reader who is interested in the role NP technology is playing in shaping the future of chemotherapeutic drug delivery and disease treatment.

Oral delivery of non-viral nucleic acid-based therapeutics - do we have the guts for this?

Gene therapy with RNA and pDNA-based drugs is limited by poor enzymatic stability and poor cellular permeation. The delivery of nucleic acids, in particular by the oral route, remains a major hurdle. This review will focus on the barriers to the oral delivery of nucleic acids and the strategies, in particular formulation strategies, which have been developed to overcome these barriers. Due to their very low oral bioavailability, the most obvious and most investigated biomedical applications for their oral delivery are related to the local treatment of inflammatory bowel diseases and colorectal cancers. Preclinical data but not yet clinical studies support the potential use of the oral route for the local delivery of formulated nucleic acid-based drugs.

Gene Therapy

Gene therapy medicinal products (GTMPs) are one of the most promising biopharmaceuticals, which are beginning to show encouraging results. The broad clinical research activity has been addressed mainly to cancer, primarily to those cancers that do not respond well to conventional treatment. GTMPs to treat rare disorders caused by single-gene mutations have also made important advancements toward market availability, with eye and hematopoietic system diseases as the main applications.Nucleic acid-marketed products are based on both in vivo and ex vivo strategies. Apart from DNA-based therapies, antisense oligonucleotides, small interfering RNA, and, recently, T-cell-based therapies have been also marketed. Moreover, the gene-editing tool CRISPR is boosting the development of new gene therapy-based medicines, and it is expected to have a substantial impact on the gene therapy biopharmaceutical market in the near future.However, despite the important advancements of gene therapy, many challenges have still to be overcome, which are discussed in this book chapter. Issues such as efficacy and safety of the gene delivery systems and manufacturing capacity of biotechnological companies to produce viral vectors are usually considered, but problems related to cost and patient affordability must be also faced to ensure the success of this emerging therapy. Graphical Abstract.

The therapeutic potential of RNA regulation in neurological disorders

INTRODUCTION

Gene regulation is the term used to describe the mechanisms by which a cell increases or decreases the amount of a gene product (RNA or protein). In complex organs such as the brain, gene regulation is of the utmost importance; aberrations in the regulation of specific genes can lead to neurological disorders. Understanding these mechanisms can create new strategies for targeting these disorders and progress is being made. Two drugs that function at the RNA level (nusinersen and eteplirsen) have now been approved by the FDA for the treatment of Spinomuscular atrophy and Duchenne muscular dystrophy, respectively; several other compounds for neurological disease are currently being investigated in preclinical studies and clinical trials. Areas covered: We highlight how gene regulation at the level of RNA molecules can be used as a therapeutic strategy to treat neurological disorders. We provide examples of how such an approach is being studied or used and discuss the current hurdles. Expert opinion: Targeting gene expression at the RNA level is a promising strategy to treat genetic neurological disorders. Safe administration, long-term efficacy, and potential side effects, however, still need careful evaluation before RNA therapeutics can be applied on a larger scale.

Cationic Liposomes Carrying siRNA: Impact of Lipid Composition on Physicochemical Properties, Cytotoxicity and Endosomal Escape

In recent year, cationic liposomes have gained a lot of attention for siRNA delivery. Despite this, intracellular barriers as endosomal escape and cytosolic delivery of siRNA still represent a challeng, as well as the cytotoxicity due to cationic lipids. To address these issues, we developed four liposomal formulations, composed of two different cationic lipids (DOTAP and DC-Cholesterol) and different ratio of co-lipids (cholesterol and DOPE). The objective is to dissect these impacts on siRNA efficacy and cytotoxicity. Liposomes were complexed to siRNA at six different N/P molar ratios, physico-chemical properties were characterized, and consequently, N/P 2.5, 5 and 10 were selected for in vitro experiments. We have shown that cytotoxicity is influenced by the N/P ratio, the concentration of cationic lipid, as well as the nature of the cationic lipid. For instance, cell viability decreased by 70% with liposomes composed of DOTAP/Cholesterol/DOPE 1/0.75/0.5 at a N/P ratio 10, whereas the same formulation at a N/P ratio of 2.5 was safe. Interestingly, we have observed differences in terms of mRNA knock-down efficiency, whereas the transfection rate was quite similar for each formulation. Liposomes containing 50% of DOPE induced a mRNA silencing of around 80%. This study allowed us to highlight crucial parameters in order to develop lipoplexes which are safe, and which induce an efficient intracytoplasmic release of siRNA.

Target-specific delivery of oxaliplatin to HER2-positive gastric cancer cells in vivo using oxaliplatin-au-fe3o4-herceptin nanoparticles

Gastric cancer is the fourth most common malignancy globally. In order to decrease the dosage and side effects of conventional chemotherapy, and achieve improved benefits from molecular targeted therapy, novel drug delivery systems were developed in the present study. Oxaliplatin-Au-Fe₃O₄-Herceptin^® acts as a dual-functional nanoparticles (NPs) conjugate and possesses the capability of human epithelial growth factor receptor 2 (HER2) targeting and oxaliplatin delivery. The 8-20 nm Au-Fe₃O₄ were synthesized by decomposing iron pentacarbonyl on the surfaces of Au NPs in the presence of oleic acid and oleylamine. Following being coated with polyethylene glycol, the NPs possessed a ζ-potential of 13.8±1.6 mV and were demonstrated to exhibit no cytotoxicity when Fe concentration is <100 µg/ml via an MTS assay. Mass spectrometry analysis detected a peak at m/z 148,000, and Nuclear Magnetic Resonance indicated peaks at δ 3.51 (8.00H, s, 3-H), 2.97-3.02 (3.80H, t, 2-H) and 2.72-2.76 (3.72H, t, 1-H) following successful loading with Herceptin and oxaliplatin probes. A drug release assay via dialysis cassettes demonstrated that 25% of the oxaliplatin was released at pH 8.0, however >58% was released at pH 6.0 following 4 h incubation, indicating its pH-dependent release characteristic. The active targeting feature of oxaliplatin-Au-Fe₃O₄-Herceptin was verified in a subcutaneous xenograft mouse model containing SGC-7901 cells via detecting aggregated low intensity in T₂-weighted magnetic resonance imaging, which was further confirmed by immunohistochemistry. Therefore, oxaliplatin-Au-Fe₃O₄-Herceptin is a promising multifunctional platform for simultaneous magnetic traceable and HER2 targeted chemotherapy for gastric cancer.

Nanotherapeutics in oral and parenteral drug delivery: Key learnings and future outlooks as we think small

Nanotechnology ushered the field of medicine in to a new era. Miniaturization, increased surface area, and the unique physicochemical properties in the nano dimension were explored for new applications. Pharmaceutical industry picked up the technology and early success came fast for oral drug delivery through improvement in dissolution properties of the active molecules. Many products were launched using the nanocrystal technology on the oral side. Further development of polymeric nanoparticles led to wide spread research of nanocarriers for parenteral delivery. While considerable efforts have gone in the last two decades for testing nanoparticles for tumor targeting, delivery into tumors has remained challenging and suboptimal. Inadequate in vivo models that didn't accurately reflect the age and vascularity of human tumors, and inability to reproducibly target therapeutic drugs to the tissue of interest due to intrinsic biodistribution of the particles and hence side effects, limited the number of studies that advanced to the clinic. Our article addresses the questions commonly asked by scientific researchers in nanomedicine: "Has nanoparticle technology yielded on its initial promise that scientists predicted towards improving therapeutic index and avoid toxicity by delivering molecules to target tissues or was it more of wishful thinking that had several roadblocks?" We answer this question by linking the relevance of nanoparticles to cancer immunotherapy. The advent of immunotherapy has begun to show the potential applicability of nanoparticles in a different light, to target the immune system. In this approach, nanoparticles may positively influence the immune system rather than create the targeted "magic bullet". Utilizing the intrinsic properties of nanoparticles for immune targeting as opposed to targeting the tumor can bring about a positive difference due to the underlying complex cancer mechanisms that can potentially overlap with the heterogeneous biodistribution of nanoparticles towards improving the acquired and innate immune responses. In this review, we have followed the progress of nanotechnology in pharmaceutical applications with key insights from oral and parenteral drug delivery, and how to modify our thinking to better utilize nanoparticles for immuno-oncology. In contrast to conventional "local" tumor targeting by nanoparticles, we propose a new mechanism whereby nanoparticles trigger priming of the T cells towards tumor destruction. The heterogenous biodistribution of nanoparticles lends itself to stimulating immune cells systemically in a "global" manner and with the right therapeutic combinations will be able to trigger tumor antigens to continually activate, retain memory effects and destroy tumor cells.