Magnetic nanoparticles coated with polyphenols for spatio-temporally controlled cancer photothermal/immunotherapy

Opportunities and Challenges of Switchable Materials for Pharmaceutical Use

Switchable polymeric materials, which can respond to triggering signals through changes in their properties, have become a major research focus for parenteral controlled delivery systems. They may enable externally induced drug release or delivery that is adaptive to in vivo stimuli. Despite the promise of new functionalities using switchable materials, several of these concepts may need to face challenges associated with clinical use. Accordingly, this review provides an overview of various types of switchable polymers responsive to different types of stimuli and addresses opportunities and challenges that may arise from their application in biomedicine.

Buffet-style Cu(II) for enhance disulfiram-based cancer therapy

Studies have shown that disulfiram (DSF) can combine with Cu²⁺ to form bis(N, N-diethyldithiocarbamate) copper(II) complex (CuET) as antitumor drugs. However, there is insufficient endogenous Cu²⁺ dose to eradicate cancer cells selectively. Inspired by the buffet, we use Cu²⁺ doped hollow zeolitic imidazolate framework nanoparticles (HZIF_Cu) as the carrier and equipped with DSF and indocyanine green (ICG) and targeted by folic acid (FA) (D&I@HZIF_Cu-FA) to enhance DSF-based cancer therapy. D&I@HZIF_Cu-FA could effectively supply Cu²⁺ by a buffet-style, assisting the "DSF-to-CuET" transformation in the tumor. Additionally, self-supply Cu²⁺ could convert H₂O₂ into ·OH by triggering a Fenton-like reaction for chemo-dynamic therapy, and ICG achieves photothermal therapy for tumors under laser irradiation. This work provides a buffet-style for Cu²⁺ to make DSF a strong candidate for cancer treatment by combining chemotherapy, chemo-dynamic therapy, and photothermal therapy and inspires more research about its applications in tumor therapy.

Functional 2D Iron-Based Nanosheets for Synergistic Immunotherapy, Phototherapy, and Chemotherapy of Tumor

Immunotherapy efficacy has been limited by tumor-associated macrophages (TAMs), which are the most abundant immune regulatory cells infiltrating around tumor tissues. The repolarization of pro-tumor M2 TAMs to anti-tumor M1 TAMs is a very promising immunotherapeutic strategy for cancer therapy. In this manuscript, multifunctional 2D iron-based nanosheets (FeNSs) are synthesized via a simple hydrothermal method for the first time, which not only possess photothermal and photodynamic properties, but also can repolarize TAMs from M2 to M1. After modifying with polyethylene glycol and loading with bioreductive prodrug banoxantrone (AQ4N), abbreviated as _AP FeNSs, it can effectively repolarize TAMs from M2 to M1 and deliver AQ4N to tumor microenvironment (TME). Moreover, the repolarized M1 TAMs overexpress inducible nitric oxide synthase, which can convert nontoxic AQ4N to cytotoxic AQ4 under hypoxic TME, enabling immunomodulation-activated chemotherapy. A series of in vitro and in vivo results corroborate that _AP FeNSs effectively exert photothermal and photodynamic effects and repolarize M2 TAMs to M1 TAMs, releasing inflammatory factors and activating the chemotherapeutic effect, thereby realizing synergistic tumor therapy.

A supramolecular self-assembled nanomaterial for synergistic therapy of immunosuppressive tumor

Triple negative breast cancer (TNBC) is an immunosuppressive "cold" tumor that lacks immune cell infiltration and activation, resulting in a poor response to immune checkpoint blockade (ICB) therapies. In addition, TNBC is poorly responsive to targeted therapies due to the absence of efficient molecular targets. A strategy that can block molecular signal transduction, stimulate immunogenicity, and activate the immune response is a promising approach to achieve ideal clinical benefit. Herein, we designed and synthesized an aggregation-induced emission luminogen (AIEgen)-conjugated self-assembling peptide that targets epidermal growth factor receptor (EGFR), named TPA-FFG-LA. TPA-FFG-LA peptides form nanoassemblies on the surface of EGFR-positive TNBC cells and are internalized into cells through endocytosis, which inhibit EGFR signaling transduction and provoke lysosomal membrane permeabilization (LMP). Upon light irradiation, the aggregated AIEgens produce massive reactive oxygen species (ROS) to exacerbate LMP and trigger immunogenic cell death (ICD), resulting in elimination of residual EGFR-negative tumor cells and exerting long-term antitumor effects. The in vitro and in vivo experiments verified that TPA-FFG-LA nanoassemblies suppress tumor growth, provoke immune cell activation and infiltration, and cause EGFR degradation and LMP. These results suggest that the combination of supramolecular assembly induced molecular targeting effects and lysosome dysfunction with ICD-stimulated immune activation is a plausible strategy for the efficient therapy of immunosuppressive TNBC.

Nanoparticle-Based Drug Delivery Systems Targeting Tumor Microenvironment for Cancer Immunotherapy Resistance: Current Advances and Applications

Cancer immunotherapy has shown impressive anti-tumor activity in patients with advanced and early-stage malignant tumors, thus improving long-term survival. However, current cancer immunotherapy is limited by barriers such as low tumor specificity, poor response rate, and systemic toxicities, which result in the development of primary, adaptive, or acquired resistance. Immunotherapy resistance has complex mechanisms that depend on the interaction between tumor cells and the tumor microenvironment (TME). Therefore, targeting TME has recently received attention as a feasibility strategy for re-sensitizing resistant neoplastic niches to existing cancer immunotherapy. With the development of nanotechnology, nanoplatforms possess outstanding features, including high loading capacity, tunable porosity, and specific targeting to the desired locus. Therefore, nanoplatforms can significantly improve the effectiveness of immunotherapy while reducing its toxic and side effects on non-target cells that receive intense attention in cancer immunotherapy. This review explores the mechanisms of tumor microenvironment reprogramming in immunotherapy resistance, including TAMs, CAFs, vasculature, and hypoxia. We also examined whether the application of nano-drugs combined with current regimens is improving immunotherapy clinical outcomes in solid tumors.

"Motile-targeting" drug delivery platforms based on micro/nanorobots for tumor therapy

Traditional drug delivery systems opened the gate for tumor-targeted therapy, but they generally took advantage of enhanced permeability and retention or ligand-receptor mediated interaction, and thus suffered from limited recognition range (<0.5 nm) and low targeting efficiency (0.7%, median). Alternatively, micro/nanorobots (MNRs) may act as emerging "motile-targeting" drug delivery platforms to deliver therapeutic payloads, thereby making a giant step toward effective and safe cancer treatment due to their autonomous movement and navigation in biological media. This review focuses on the most recent developments of MNRs in "motile-targeting" drug delivery. After a brief introduction to traditional tumor-targeted drug delivery strategies and various MNRs, the representative applications of MNRs in "motile-targeting" drug delivery are systematically streamlined in terms of the propelling mechanisms. Following a discussion of the current challenges of each type of MNR in biomedical applications, as well as future prospects, several promising designs for MNRs that could benefit in "motile-targeting" drug delivery are proposed. This work is expected to attract and motivate researchers from different communities to advance the creation and practical application of the "motile-targeting" drug delivery platforms.

Photothermal Nano-Vaccine Promoting Antigen Presentation and Dendritic Cells Infiltration for Enhanced Immunotherapy of Melanoma via Transdermal Microneedles Delivery

Immunotherapy has demonstrated the potential to cure melanoma, while the current response rate is still unsatisfactory in clinics. Extensive evidence indicates the correlation between the efficacy and pre-existing T-cell in tumors, whereas the baseline T-cell infiltration is lacking in low-response melanoma patients. Herein, we demonstrated the critical contribution of dendritic cells (DCs) on melanoma survival and baseline T-cell level, as well as the efficacy of immunotherapy. Capitalized on this fact, we developed a photothermal nano-vaccine to simultaneously promote tumor antigens presentation and DCs infiltration for enhanced immunotherapy. The nano-vaccine was composed of polyserotonin (PST) core and tannic acid (TA)/Mn2+ coordination-based metal-organic-framework (MOF) shell for β-catenin silencing DNAzyme loading, which was further integrated into dissolving microneedles to allow noninvasive and transdermal administration at melanoma skin. The nano-vaccine could rapidly penetrate skin upon microneedles insertion and exert a synergistically amplified photothermal effect to induce immunogenic cell death (ICD). The MOF shell then dissociated and released Mn2+ as a cofactor to self-activate DNAzyme for β-catenin suppression, which in turn caused a persistent CCL4 excretion to promote the infiltration of DCs into the tumor. Meanwhile, the liberated PST core could effectively capture and facilitate tumor antigens presentation to DCs. As a result, potent antitumor efficacies were achieved for both primary and distal tumors without any extra treatment, indicating the great promise of such a nano-vaccine for on-demand personalized immunotherapy of melanoma.

High Drug-Loading Nanomedicines for Tumor Chemo-Photo Combination Therapy: Advances and Perspectives

The combination of phototherapy and chemotherapy (chemo−photo combination therapy) is an excellent attempt for tumor treatment. The key requirement of this technology is the high drug-loading nanomedicines, which can load either chemotherapy drugs or phototherapy agents at the same nanomedicines and simultaneously deliver them to tumors, and play a multimode therapeutic role for tumor treatment. These nanomedicines have high drug-loading efficiency (>30%) and good tumor combination therapeutic effect with important clinical application potential. Although there are many reports of high drug-loading nanomedicines for tumor therapy at present, systematic analyses on those nanomedicines remain lacking and a comprehensive review is urgently needed. In this review, we systematically analyze the current status of developed high drug-loading nanomedicines for tumor chemo−photo combination therapy and summarize their types, methods, drug-loading properties, in vitro and in vivo applications. The shortcomings of the existing high drug-loading nanomedicines for tumor chemo−photo combination therapy and the possible prospective development direction are also discussed. We hope to attract more attention for researchers in different academic fields, provide new insights into the research of tumor therapy and drug delivery system and develop these nanomedicines as the useful tool for tumor chemo−photo combination therapy in the future.

Synthesis of multi-branched Au nanocomposites with distinct plasmon resonance in NIR-II window and controlled CRISPR-Cas9 delivery for synergistic gene-photothermal therapy

Clinical implementation of photothermal therapy (PTT) is mainly hampered by limited tissue penetration, undesirable thermal damage to normal tissues, and thermotolerence induced by heat shock proteins (HSPs). To overcome these obstacles, we constructed a novel gene-photothermal synergistic therapeutic nanoplatform composed of a multi-branched Au nanooctopus (AuNO) core and mesoporous polydopamine (mPDA) shell, followed by CRISPR-Cas9 ribonucleoprotein (RNP) loading and then polyethylene glycol-folic acid (PEG-FA) coating. AuNO was simply synthesized by adjusting the ratio of cetyltrimethylammonium chloride (CTAC) and cetyltrimethylammonium bromide (CTAB), which showed significant localized surface plasmon resonances in the NIR-II window, and exhibited an excellent tissue penetration capability and high photothermal conversion efficiency (PCE, 47.68%). Even, the PCE could be further increased to 66.17% by mPDA coating. Furthermore, the sequential modification of AuNO@mPDA using RNP and PEG-FA can down-regulate HSP90α expression at tumor sites, enhance apoptosis and reduce the heat resistance of cancer cells. The synergistic effect of enhanced photothermal capacity and reduced thermoresistance addressed the multiple limitations of PTT, and presented excellent in vitro and in vivo antitumor efficacy, having great potential for the clinical application of PTT.

Immunosonodynamic Therapy Designed with Activatable Sonosensitizer and Immune Stimulant Imiquimod

Sonodynamic therapy (SDT) has garnered extensive attention as a noninvasive treatment for deep tumors. Furthermore, imiquimod (R837), an FDA-approved toll-like receptor 7 agonist, is commonly used in clinical settings as an immune adjuvant. We prepared an activatable sonodynamic sensitizer platform (MR) based on glutathione-sensitive disulfide bonds linking Leu-MB, the reduced form of methylene blue (MB), and R837 to achieve efficient combinatory SDT and immunotherapy for tumors without harming normal tissues. We also used the amphiphilic polymer C₁₈PMH-PEG to create self-assembled MB-R837-PEG (MRP) nanoparticles for immunosonodynamic therapy (iSDT). iSDT is a cancer treatment that combines activatable SDT and immunotherapy. Our iSDT demonstrated an excellent sonodynamic effect only at the tumor site, demonstrating high specificity in killing tumor cells when compared to SDT reported in the literature. The iSDT improves its tumor-killing effect by inducing an immune response, which is accomplished by secreted immune adjuvants in the tumor site. MRP was selectively activated by glutathione in the tumor microenvironment to release MB and R837, exhibiting excellent antitumor sonodynamic and immune responses. In addition, when combined with an α-PD-L1 antibody for immune checkpoint blockade, this therapy effectively inhibited tumor metastasis. Furthermore, mice treated with iSDT and α-PD-L1 antibody did not develop tumors even after tumor reinoculation, indicating that long-term immune memory was achieved. The concept of sonodynamic sensitizer preparation as a next-generation iSDT based on a noninvasive synergistic therapeutic modality applicable in the near future is presented in this study.

Trends in iron oxide nanoparticles: a nano-platform for theranostic application in breast cancer

Breast cancer (BC) is the deadliest malignant disorder globally, with a significant mortality rate. The development of tolerance throughout cancer treatment and non-specific targeting limits the drug's response. Currently, nano therapy provides an interdisciplinary area for imaging, diagnosis, and targeted drug delivery for BC. Several overexpressed biomarkers, proteins, and receptors are identified in BC, which can be potentially targeted by using nanomaterial for drug/gene/immune/photo-responsive therapy and bio-imaging. In recent applications, magnetic iron oxide nanoparticles (IONs) have shown tremendous attention to the researcher because they combine selective drug delivery and imaging functionalities. IONs can be efficaciously functionalised for potential application in BC therapy and diagnosis. In this review, we explored the current application of IONs in chemotherapeutics delivery, gene delivery, immunotherapy, photo-responsive therapy, and bio-imaging for BC based on their molecular mechanism. In addition, we also highlighted the effect of IONs' size, shape, dimension, and functionalization on BC targeting and imaging. To better comprehend the functionalization potential of IONs, this paper provides an outline of BC cellular development. IONs for BC theranostic are also reviewed based on their clinical significance and future aspects.

Mussel-Inspired Ligand Clicking and Ion Coordination on 2D Black Phosphorus for Cancer Multimodal Imaging and Therapy

As a promising 2D nanocarrier, the biggest challenge of bare black phosphorus nanosheets (BP NSs) lies in the inherent instability, while it can be improved by surface modification strategies to a great extent. Considering the existing infirm BP NSs surface modification strategies, A mussels-inspired strong adhesive biomimetic peptide with azide groups for surface modification to increase the stability of BP NSs is synthesized. The azide groups on the peptide can quickly and precisely bind to the targeting ligand through click chemistry, solving the problem of nonspecificity of secondary modification of other mussel-mimicking materials. Besides, a catechol-Gd³⁺ coordination network is further constructed for magnetic resonance imaging (MRI) and inducing intracellular endo/lysosome escape. The fabricated BP-DOX@Gd/(DOPA)₄ -PEG-TL nanoplatform exhibits enhanced antitumor abilities through synergetic chemo/photothermal effects both in vitro and in vivo.

Polysialylated nanoinducer for precisely enhancing apoptosis and anti-tumor immune response in B-cell lymphoma

B-cell lymphoma is one of the most common types of lymphoma, and chemotherapy is still the current first-line treatment. However, due to the systemic side effects caused by chemotherapy drugs, traditional regimens have limitations and are difficult to achieve ideal efficacy. Recent studies have found that CD22 (also known as Siglec-2), as a specific marker of B-cells, is significantly up-regulated on B-cell lymphomas. Inspired by the specific recognition and binding of sialic acid residues by CD22, a polysialic acid (PSA)-modified PLGA nanocarrier (SAPC NP) designed to target B-cell lymphoma was fabricated. Mitoxantrone (MTO) was further loaded into SAPC NP through hydrophobic interactions to obtain polysialylated immunogenic cell death (ICD) nanoinducer (MTO@SAPC NP). Cellular experiments confirmed that MTO@SAPC NP could be specifically taken up by two types of CD22⁺ B lymphoma cells including Raji and Ramos cells, unlike the poor endocytic performance in other lymphocytes or macrophages. MTO@SAPC NP was determined to enhance the ICD and show better apoptotic effect on CD22⁺ cells. In the mouse model of B-cell lymphoma, MTO@SAPC NP significantly reduced the systemic side effects of MTO through lymphoma targeting, then achieved enhanced anti-tumor immune response, better tumor suppressive effect, and improved survival rate. Therefore, the polysialylated ICD nanoinducer provides a new strategy for precise therapy of B-cell lymphoma. STATEMENT OF SIGNIFICANCE: • Polysialic acid functionalized nanocarrier (SAPC NP) was designed and prepared. • SAPC NP is specifically endocytosed by two CD22⁺ B lymphoma cells. • Mitoxantrone-loaded nanoinducer (MTO@SAPC NP) promote immunogenic cell death and anti-tumor immune response. • "Polysialylation" is a potential new approach for precision treatment of B-cell lymphoma.

Vascular bursts-mediated tumor accumulation and deep penetration of spherical nucleic acids for synergistic radio-immunotherapy

While nanomedicines have attracted great interests for tumor therapy, their targeting and intra-tumoral penetrating efficiencies have been questioned. Here, we report a two-step low-dose radiotherapy (RT) strategy to realize significant accumulation and deep penetration of spherical nucleic acids (SNAs)-based nanomedicine for synergistic radio-immunotherapy. The first step RT was employed to recruit large amounts of macrophages into tumor. The tumor infiltrated macrophages not only served as nanoparticles drug depots, but also elicited dynamic bursts extravasation to enhance nanoparticles accumulation. We optimized the spatiotemporal combination of RT and SNAs administration for higher level of SNAs delivery, and the delivered SNAs promote M2-to-M1 phenotype switch of macrophages to increase phagocytosis of nanoparticles by 6-fold, resulting in positive feedback with even higher accumulation and intra-tumor penetration of SNAs. Through vascular bursts and macrophage repolarization, as high as 25-fold enhancement of nanoparticles accumulation was achieved as compared to passive targeting of nanoparticles, and the nanoparticles were eventually distributed throughout the tumor tissue with efficient deep penetration. Finally, SNAs in tumor simultaneously sensitized the second dose of RT and remodeled tumor immune microenvironment, resulting in a synergistic anticancer therapy in combination of anti-PD-L1 antibody (αPD-L1) with no noticeable side effects caused by either RT or αPD-L1.

Ag nanoparticles enhance immune checkpoint blockade efficacy by promoting of immune surveillance in melanoma

Immune checkpoint blockade (ICB) therapy, represented by programmed cell death protein 1 (PD-1) and its ligand (PD-L1) monoclonal antibodies (mAbs), has shown an obvious benefit for melanoma immunotherapy, but the overall response rate is still low. To find an effective combination therapy strategy, we successfully produced small size silver nanoparticles coated with sucrose (S-AgNPs) as potent adjuvants. The antitumor effects of S-AgNPs were tested in vitro and comparatively investigated in immunodeficient and immunocompetent mice with melanoma. Fluorescence-activated cell sorting and immunofluorescent staining analysis were conducted to identify the tumor microenvironments. The expression of PD-L1 in tumors was tested by multiple methods. The combination therapy and potential toxicity of S-AgNPs and PD-1 mAbs were assessed in melanoma-bearing mice. In our findings, S-AgNPs presented potent antitumor effects, good druggability and low systemic toxicity. Functionally, we found that S-AgNPs exhibited better antitumor effects in immunocompetent mice. Mechanistically, we showed that S-AgNPs suppress tumor cell proliferation by inducing cellular apoptosis and promote cytotoxic CD8+ T cell infiltration and activity. Preclinically, S-AgNPs showed excellent local antitumor activity and mild systemic immunotoxicity with PD-1 mAbs in the inhibition of melanoma proliferation, providing a novel clinical combination treatment strategy.

Dual-binding nanoparticles improve the killing effect of T cells on solid tumor

Adoptive cell therapy (ACT) was one of the most promising anti-tumor modalities that has been confirmed to be especially effective in treating hematological malignancies. However, the clinical efficacy of ACT on solid tumor was greatly hindered by the insufficient tumor-infiltration of cytotoxic CD8 + T cells. Herein, we constructed a nanoplatform termed dual-binding magnetic nanoparticles (DBMN) that comprised PEG-maleimide (Mal), hyaluronic acid (HA) and Fe3O4 for adoptive T cell-modification and ACT-sensitization. After a simple co-incubation, DBMN was anchored onto the cell membrane (Primary linking) via Michael addition reaction between the Mal and the sulfhydryl groups on the surface of T cells, generating magnetized T cells (DBMN-T). Directed by external magnetic field and in-structure Fe3O4, DBMN-T was recruited to solid tumor where HA bond with the highly expressed CD44 on tumor cells (Secondary Linking), facilitating the recognition and effector-killing of tumor cells. Bridging adoptive T cells with host tumor cells, our DBMN effectively boosted the anti-solid tumor efficacy of ACT in a mouse model and simultaneously reduced toxic side effects.

Heptamethine Cyanine-Loaded Nanomaterials for Cancer Immuno-Photothermal/Photodynamic Therapy: A Review

The development of strategies capable of eliminating metastasized cancer cells and preventing tumor recurrence is an exciting and extremely important area of research. In this regard, therapeutic approaches that explore the synergies between nanomaterial-mediated phototherapies and immunostimulants/immune checkpoint inhibitors have been yielding remarkable results in pre-clinical cancer models. These nanomaterials can accumulate in tumors and trigger, after irradiation of the primary tumor with near infrared light, a localized temperature increase and/or reactive oxygen species. These effects caused damage in cancer cells at the primary site and can also (i) relieve tumor hypoxia, (ii) release tumor-associated antigens and danger-associated molecular patterns, and (iii) induced a pro-inflammatory response. Such events will then synergize with the activity of immunostimulants and immune checkpoint inhibitors, paving the way for strong T cell responses against metastasized cancer cells and the creation of immune memory. Among the different nanomaterials aimed for cancer immuno-phototherapy, those incorporating near infrared-absorbing heptamethine cyanines (Indocyanine Green, IR775, IR780, IR797, IR820) have been showing promising results due to their multifunctionality, safety, and straightforward formulation. In this review, combined approaches based on phototherapies mediated by heptamethine cyanine-loaded nanomaterials and immunostimulants/immune checkpoint inhibitor actions are analyzed, focusing on their ability to modulate the action of the different immune system cells, eliminate metastasized cancer cells, and prevent tumor recurrence.

A Perfect Pair: Stabilized Black Phosphorous Nanosheets Engineering with Antimicrobial Peptides for Robust Multidrug Resistant Bacteria Eradication

Black phosphorus (BP) nanosheets emerged as promising 2D nanomaterial that have been applied to eradicate antibiotic-resistant bacteria. However, their applications are limited by intrinsic ambient instability. Here, the ε-poly-l-lysine (ε-PL)-engineered BP nanosheets are constructed via simple electrostatic interaction to cater the demand for passivating BP with amplified antibacterial activity. The dual drug-delivery complex named BP@ε-PL can closely anchor onto the surface of bacteria, leading to membrane disintegration. Subsequently, in situ hyperthermia generated by BP under near-infrared (NIR) irradiation can precisely eradicate pathogenic bacteria. In vitro antibacterial studies verify the rapid disinfection ability of BP@ε-PL against Methicillin-resistant Staphylococcus aureus (MRSA) within 15 min. Moreover, ε-PL can serve as an effective protector to avoid chemical degradation of bare BP. The in vivo antibacterial study shows that a 99.4% antibacterial rate in a MRSA skin infection model is achieved, which is accompanied by negligible toxicity. In conclusion, this work not merely provides a new conjecture for protecting the BP, but also opens a novel window for synergistic antibiotic-resistant bacteria therapy based on antimicrobial peptides and 2D photothermal nanomaterial.

Trauma-Responsive Scaffold Synchronizing Oncolysis Immunization and Inflammation Alleviation for Post-Operative Suppression of Cancer Metastasis

Tumor surgery can create an inflammatory trauma to aggravate residual tumor "seed" to colonize pre-metastatic niches (PMNs) "soil" at secondary sites, thereby promoting post-operative metastasis. However, two-pronged strategies for post-surgical elimination of asynchronous "seeds" and "soil" at different regions are currently lacking. Here, we have designed a hydrogel that can be injected into a resection cavity, where it immediately forms a scaffold and gradually degrades responding to enriched reactive oxygen species at adjacent trauma for local delivery and on-demand release of autologous cancer cells succumbing to oncolysis (ACCO) and anti-inflammatory agent. The autologous cell source self-provides a whole array of tumor-associated antigens, and the oncolysis orchestration of a subcellular cascade confers a self-adjuvanting property, together guaranteeing high immunogenicity of the ACCO vaccine that enables specific antitumor immunization. In parallel, inflammation alleviation exerted bidirectional functions to reshape the local immune landscape and resuscitate ACCO, leading to the eradication of residual tumor "seeds" while simultaneously intercepting the "seed-soil" crosstalk to normalize distant lung leading to regression of pre-existing PMN "soil". As a result, regional and metastatic recurrence were completely thwarted. Together, this framework synchronizing oncolysis immunization and inflammation alleviation provides an effective option for post-operative suppression of metastasis.

Sonosensitizer nanoplatform-mediated sonodynamic therapy induced immunogenic cell death and tumor immune microenvironment variation

Epithelial ovarian cancer (EOC) is one of the most lethal gynecologic malignancies, and effective treatments are still lacking due to drug tolerance and tumor recurrence. In this study, we aimed to investigate the effects of sonodynamic therapy (SDT) on ovarian cancer and its potential mechanism. Folate receptor-targeted and ultrasound-responsive nanoparticles (NPs) were constructed using PLGA-PEG-FA (PLGA: poly (lactic-co-glycolic) acid, polyethylene glycol (PEG), FA: folate), the reactive oxygen species (ROS)-generating sonosensitizer IR780 and the oxygen-carrying material perfluorohexane (PFH), termed IRO@FA NPs. The antitumor effect of NPs triggered by ultrasound (US) was measured by an apoptosis assay in a C57/BL6 mouse model. Immunochemistry and flow cytometry were used to detect the proportion of CD3⁺ T, CD4⁺ T, CD8⁺ T cells and activated dendritic cells (DCs) in spleens and tumor tissues to assess variation in the immune response. Moreover, endoplasmic reticulum (ER) stress and immunogenic cell death (ICD) markers (high mobility group protein box-1, ATP and calreticulin) were detected to identify potential mechanisms. The results showed that IRO@FA NP-mediated SDT promoted ID8 cell apoptosis both in vitro and in vivo. The densities of CD3⁺ and CD8⁺ T lymphocytes and inflammatory markers were upregulated in tumor tissues. IRO@FA NP-mediated SDT prompted DC maturation and T lymphocyte infiltration by inducing ID8 cell ICD.

Heterojunction engineered bioactive chlorella for cascade promoted cancer therapy

The hypoxic tumor microenvironment is one of most major hurdles restraining the anti-tumor efficiency of photodynamic therapy (PDT). Herein, active photosynthetic Chlorophyceae (Chlorella, Chl) functionalized with black phosphorus nanosheets (BPNSs) through polyaspartic acid (PASP) and Fe³⁺ mediating "Lego building method" are utilized for photocatalyzed oxygen-evolving to realize photosynthesis enhanced synergistic photodynamic/chemodynamic/immune therapy. The Chl cells with inherent photosynthesis and distinct metabolites are able to ameliorate tumor hypoxia, enhance immune cells infiltration, and stimulate the proliferation and maturation of immune cells. BPNSs loaded on the surface of Chl cells construct a type-II heterojunction with the chlorophyll in Chl cells, which improves the conversion efficiency of light through thoroughly separating photo-excited electrons and holes for ¹O₂ generation and O₂ evolution, respectively. Additionally, the lock between "Lego bricks", Fe³⁺, can both consume glutathione (GSH) and catalyze Fenton reaction with H₂O₂ to generate ·OH, mediating chemodynamic therapy (CDT). Moreover, Chl@BP-Fe also exhibited high biocompatibility and potential biodegradability, guaranteeing high potential for clinic applications of this synergistic photodynamic/chemodynamic/immune therapy.

Architecting polyelectrolyte hydrogels with Cu-assisted polydopamine nanoparticles for photothermal antibacterial therapy

Polydopamine nanoparticles (PDA NPs) are an appealing biomimetic photothermal agent for photothermal antibacterial treatment because of their long-term safety, excellent photostability, accessible manufacturing, and good biodegradability. However, the low photothermal conversion efficiency (PCE) of PDA NPs requires high-power and long-term near-infrared light irradiation, which severely restricts their practical application. In this work, PDA@Cu NPs were fabricated by growing Cu NPs in situ on the surface of PDA and then introduced into a polyelectrolyte hydrogel precursor (cationic polyethyleneimine/anionic pectin, named as CPAP). The formulated photothermal platform possessed a high PCE (55.4%), almost twice as much as pure PDA NPs (30.8%). Moreover, the designed CPAP/PDA@Cu captured and killed some bacteria by electrostatic adsorption, which helped enhance the antibacterial performance. As expected, the formed CPAP/PDA@Cu that combined the advantageous features of PDA@Cu NPs (high PCE) and CPAP matrix (inherent antibacterial activity and preventing NPs aggregation) can efficiently kill bacteria both in vitro and in vivo under the help of near-infrared laser irradiation. Taken together, this study offers a promising strategy for constructing a facile and safe PDA-based photothermal agent for photothermal antibacterial therapy.

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A facile polyelectrolyte photothermal antibacterial platform (CPAP) was synthesized.

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CPAP is composed of polyethyleneimine, pectin and polydopamine@Cu nanoparticles.

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CPAP displayed good biocompatibility and tunable physicochemical properties.

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CPAP possessed outstanding high-efficiency bacteria-killing capability.

Engineered gold/black phosphorus nanoplatforms with remodeling tumor microenvironment for sonoactivated catalytic tumor theranostics

The imbalance between oxidants and antioxidants in cancer cells would evoke oxidative stress-induced cell death, which has been demonstrated to be highly effective in treating malignant tumors. Sonodynamic therapy (SDT) adopts ultrasound (US) as the excitation source to induce the production of reactive oxygen species (ROS), which emerges as a noninvasive therapeutic strategy with deep tissue penetration depth and high clinical safety. Herein, we construct novel sonoactivated oxidative stress amplification nanoplatforms by coating MnO2 on Au nanoparticle-anchored black phosphorus nanosheets and decorating soybean phospholipid subsequently (Au/BP@MS). The Au/BP@MS exhibit increased ROS generation efficiency under US irradiation in tumor tissues due to Au/BP nanosensitizer-induced improvement of electron-hole separation as well as MnO2-mediated O2 generation and GSH depletion, thus leading to notable inhibition effect on tumor growth. Moreover, tumor microenvironment-responsive biodegradability of Au/BP@MS endows them with enhanced magnetic resonance imaging guidance and clinical potential for cancer theranostics.

Current advances in the imaging of atherosclerotic vulnerable plaque using nanoparticles

Vulnerable atherosclerotic plaques of the artery wall that pose a significant risk of cardio-cerebral vascular accidents remain the global leading cause of morbidity and mortality. Thus, early delineation of vulnerable atherosclerotic plaques is of clinical importance for prevention and treatment. The currently available imaging technologies mainly focus on the structural assessment of the vascular wall. Unfortunately, several disadvantages in these strategies limit the improvement in imaging effect. Nanoparticle technology is a novel diagnostic strategy for targeting and imaging pathological biomarkers. New functionalized nanoparticles that detect hallmarks of vulnerable plaques are promising for advance further control of this critical illness. The review aims to address the current opportunities and challenges for the use of nanoparticle technology in imagining vulnerable plaques.

Tumor-associated macrophages in cancer: recent advancements in cancer nanoimmunotherapies

Cancer immunotherapy has emerged as a novel cancer treatment, although recent immunotherapy trials have produced suboptimal outcomes, with durable responses seen only in a small number of patients. The tumor microenvironment (TME) has been shown to be responsible for tumor immune escape and therapy failure. The vital component of the TME is tumor-associated macrophages (TAMs), which are usually associated with poor prognosis and drug resistance, including immunotherapies, and have emerged as promising targets for cancer immunotherapy. Recently, nanoparticles, because of their unique physicochemical characteristics, have emerged as crucial translational moieties in tackling tumor-promoting TAMs that amplify immune responses and sensitize tumors to immunotherapies in a safe and effective manner. In this review, we mainly described the current potential nanomaterial-based therapeutic strategies that target TAMs, including restricting TAMs survival, inhibiting TAMs recruitment to tumors and functionally repolarizing tumor-supportive TAMs to antitumor type. The current understanding of the origin and polarization of TAMs, their crucial role in cancer progression and prognostic significance was also discussed in this review. We also highlighted the recent evolution of chimeric antigen receptor (CAR)-macrophage cell therapy.

pH-Sensitive and Charge-Reversal Polymeric Nanoplatform Enhanced Photothermal/Photodynamic Synergistic Therapy for Breast Cancer

As reported, breast cancer is one of the most common malignancies in women and has overtaken lung cancer as the most commonly diagnosed cancer worldwide by 2020. Currently, phototherapy is a promising anti-tumor therapy due to its fewer side effects, less invasiveness, and lower cost. However, its application in cancer therapeutics is limited by the incomplete therapeutic effect caused by low drug penetration and monotherapy. Herein, we built a charge-reversal nanoplatform (Ce6-PLGA@PDA-PAH-DMMA NPs), including polydopamine (PDA) and chlorin e6 (Ce6) for enhancing photothermal/photodynamic synergistic therapy. The PAH-DMMA charge-reversal layer enabled Ce6-PLGA@PDA-PAH-DMMA NPs to have long blood circulation at the normal physiological environment and to successfully realize charge reversal under the weakly acidic tumor microenvironment, improving cellular uptake. Besides, in vitro tests demonstrated that Ce6-PLGA@PDA-PAH-DMMA NPs had high photothermal conversion and greater anti-tumor activity than no charge-reversal nanoparticles, which overcame the limited tumor therapeutic efficacy of PTT or photodynamic therapy alone. Overall, the design of pH-responsive and charge-reversal nanoparticles (Ce6-PLGA@PDA-PAH-DMMA NPs) provided a promising approach for synergistic PTT/PDT therapy against breast cancer.

Symphony of nanomaterials and immunotherapy based on the cancer-immunity cycle

The immune system is involved in the initiation and progression of cancer. Research on cancer and immunity has contributed to the development of several clinically successful immunotherapies. These immunotherapies often act on a single step of the cancer–immunity cycle. In recent years, the discovery of new nanomaterials has dramatically expanded the functions and potential applications of nanomaterials. In addition to acting as drug-delivery platforms, some nanomaterials can induce the immunogenic cell death (ICD) of cancer cells or regulate the profile and strength of the immune response as immunomodulators. Based on their versatility, nanomaterials may serve as an integrated platform for multiple drugs or therapeutic strategies, simultaneously targeting several steps of the cancer–immunity cycle to enhance the outcome of anticancer immune response. To illustrate the critical roles of nanomaterials in cancer immunotherapies based on cancer–immunity cycle, this review will comprehensively describe the crosstalk between the immune system and cancer, and the current applications of nanomaterials, including drug carriers, ICD inducers, and immunomodulators. Moreover, this review will provide a detailed discussion of the knowledge regarding developing combinational cancer immunotherapies based on the cancer–immunity cycle, hoping to maximize the efficacy of these treatments assisted by nanomaterials.

Fabrication of human serum albumin–imprinted photothermal nanoparticle for enhanced immunotherapy

Photothermal nanoparticles have been confirmed to induce antitumor immune response and turn “cold tumor” into “hot tumor”. However, their delivery efficacy to tumors is limited by the elimination from the...

Dual peptide nanoparticles platform for enhanced antigen-specific immune tolerance for treatment of experimental autoimmune encephalomyelitis

Current therapeutic strategies for autoimmune diseases including multiple sclerosis (MS) are directed toward nonspecific immunosuppression which has severe side effects. The induction of antigen-specific tolerance becomes an ideal therapy for...

Nanoparticles with rough surface improve the therapeutic effect of photothermal immunotherapy against melanoma

Photothermal therapy has been intensively investigated for treating cancer in recent years. However, the long-term therapeutic outcome remains unsatisfying due to the frequently occurred metastasis and recurrence. To address this challenge, immunotherapy has been combined with photothermal therapy to activate anti-tumor immunity and relieve the immunosuppressive microenvironment within tumor sites. Here, we engineered silica-based core‒shell nanoparticles (JQ-1@PSNs-R), in which silica cores were coated with the photothermal agent polydopamine, and a bromodomain-containing protein 4 (BRD4) inhibitor JQ-1 was loaded in the polydopamine layer to combine photothermal and immune therapy for tumor elimination. Importantly, to improve the therapeutic effect, we increased the surface roughness of the nanoparticles by hydrofluoric acid (HF) etching during the fabrication process, and found that the internalization of JQ-1@PSNs-R was significantly improved, leading to a strengthened photothermal killing effect as well as the increased intracellular delivery of JQ-1. In the animal studies, the multifunctional nanoparticles with rough surfaces effectively eradicated melanoma via photothermal therapy, successfully activated tumor-specific immune responses against residual tumor cells, and further prevented tumor metastasis and recurrence. Our results indicated that JQ-1@PSNs-R could serve as an innovative and effective strategy for combined cancer therapy.

Nanoparticle Systems for Cancer Phototherapy: An Overview

Photodynamic therapy (PDT) and photothermal therapy (PTT) are photo-mediated treatments with different mechanisms of action that can be addressed for cancer treatment. Both phototherapies are highly successful and barely or non-invasive types of treatment that have gained attention in the past few years. The death of cancer cells because of the application of these therapies is caused by the formation of reactive oxygen species, that leads to oxidative stress for the case of photodynamic therapy and the generation of heat for the case of photothermal therapies. The advancement of nanotechnology allowed significant benefit to these therapies using nanoparticles, allowing both tuning of the process and an increase of effectiveness. The encapsulation of drugs, development of the most different organic and inorganic nanoparticles as well as the possibility of surfaces' functionalization are some strategies used to combine phototherapy and nanotechnology, with the aim of an effective treatment with minimal side effects. This article presents an overview on the use of nanostructures in association with phototherapy, in the view of cancer treatment.

Heat-Confined Tumor-Docking Reversible Thermogel Potentiates Systemic Antitumor Immune Response During Near-Infrared Photothermal Ablation in Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC) features immunologically "cold" tumor microenvironments with limited cytotoxic T lymphocyte (CTL) infiltration. Although ablation therapies have demonstrated modulation of "cold" TNBC tumors to inflamed "hot" tumors, recruitment of myeloid derived suppressor cells (MDSCs) at the tumors post ablation therapies prevents the infiltration of CTLs and challenge the antitumor potentials of T-cell therapies. Here, a thermal ablation immunotherapy strategy is developed to prevent the immune suppressive effects of MDSCs during photothermal ablation and induce a durable systemic antitumor immunity to eradicate TNBC tumors. An injectable pluronic F127/hyaluronic acid (HA)-based hydrogel embedded with manganese dioxide (BM) nanoparticles and TLR7 agonist resiquimod (R848) (BAGEL-R848), is synthesized to induce in situ laser-assisted gelation of the hydrogel and achieve desired ablation temperatures at a low laser-exposure time. Upon 808-nm laser irradiation, a significant reduction in the tumor burden is observed in BAGEL-R848-injected 4T1 tumor-bearing mice. The ablation induced immunogenic cell death and sustained release of R848 from BAGEL-R848 promotes dendritic cell maturation and reduced MDSCs localization in tumors. In addition, inflammatory M1 macrophages and CD8+IFN+ CTL are enriched in distant tumors in bilateral 4T1 tumor model, preventing metastatic tumor growth and signifying the potential of BAGEL-R848 to treat TNBC.

Synergistic chemo-photothermal cancer therapy of pH-responsive polymeric nanoparticles loaded IR825 and DTX with charge-reversal property

IR825 is a kind of near-infrared (NIR) small molecule cyanine dye and has distinct near-infrared absorbance and excellent thermal conversion performance. Due to poor stability and insufficient therapy efficacy, various nano-systems have been developed as delivery vehicles for NIR dyes to improve their application in tumor treatment. Herein, we developed an intelligent polymer drug vehicle (Mal-PAH-PEG-DMMA/ poly (ethylene imine) - poly(ε-caprolactone) block polymers, MPPD/PEI-PCL) based on pH-responsive charge-reversal to deliver docetaxel (DTX) and photosensitizer (IR825) for chemo-photothermal combination therapy (MPPD@IR825/DTX NPs). MPPD@IR825/DTX NPs could undergo charge conversion in a slightly acidic microenvironment (pH 6.8), resulted in strong electrostatic repulsion to withdraw the shell of the polymer nanoparticles (MPPD), enhanced cellular uptake and increased drug release. MPPD@IR825/DTX NPs demonstrated nanoscale in size with good mono-dispersity and stability, triggered DTX release in response to acid environment and NIR stimulation, in the same time providing excellent photothermal conversion efficiency. In vitro and In vivo experiments confirmed that charge-reversal polymeric nanoparticles improved antitumor efficiency in 4T1 tumor cell modal than non-charge-reversal polymeric nanoparticles. Furthermore, in comparison with chemotherapy or photothermal therapy in a single treatment mode, chemo-photothermal combination therapy of MPPD@IR825/DTX NPs with laser irradiation showed highly efficient tumor ablation. In addition, the polymeric nanoparticles exhibited good biocompatibility and safety. Therefore, the design of charge-reversal polymeric nanoparticles (MPPD@IR825/DTX NPs) provides a new strategy and promising application for targeting and synergistic chemo-photothermal combination therapy.

Were magnetic materials useful in cancer therapy?

Cancer is one of the major challenges fronting the biomedical basic researches in our time. The study and development of effective therapeutic strategies for cancer therapy are vital. Among the many probable core constituents of nanoparticles, magnetite-based nanoparticles have been widely studied for cancer therapy owing to their inherent magnetic features, multifunctional design, biodegradable and biocompatible properties. Magnetic nanoparticles have been also designed for utilizing as contrast enhancer agents for magnetic resonance imaging, drug delivery systems, and most recently as a therapeutic element in inducing cellular death in tumor ablation therapies. This review aimed to provide an overview of the various applications of magnetic nanoparticles and recent achievements in developing these advanced materials for cancer therapy.

Charge-reversal biodegradable MSNs for tumor synergetic chemo/photothermal and visualized therapy

Given the difficulties of biodegradation of mesoporous silica nanoparticles (NPs), enrichment and penetration of tumor sites, and real-time monitoring of the treatment process, we developed a kind of mannose-doping doxorubicin-loading mesoporous silica nanoparticle (MSN-Man-DOX) and coated by polydopamine-Gd³⁺ (PDAGd) metal-phenolic networks, as well as modified by poly (2-Ethyl-2-Oxazoline) (PEOz), constructing a novel nanomedicine MSN-Man-DOX@PDA-Gd-PEOz. Its pH-responsive charge reversal, photothermal, biodegradation, drug release, and magnetic resonance imaging (MRI) properties were evaluated in vitro. Cellular uptake, tumor penetration, lysosomal escape properties, as well as cell safety and toxicity of the nanoplatform were investigated through cell experiments. Finally, the MRI, organ distribution, photothermal condition, and comprehensive anti-tumor therapy in vivo were evaluated comprehensively through animal experiments. Research results showed that MSN-Man-DOX@PDA-Gd-PEOz had outstanding tumor enrichment and penetration abilities, which can produce excellent treatment effects through the synergistic effect of chemotherapy and photothermal therapy (PTT) with the function of magnetic resonance imaging contrast agent for disease monitoring. Besides, after finishing the therapeutic effect MSN-Man-DOX@PDA-Gd-PEOz can be biodegraded, so it had a good prospect of clinical application.

Long-Term Stable Near-Infrared-Short-Wave-Infrared Photodetector Driven by the Photothermal Effect of Polypyrrole Nanostructures

Polypyrrole (PPy) is a conductive polymer and widely applied in different applications owing to its broadband absorption in the UV-visible, near-infrared (NIR), and short-wave-infrared (SWIR) spectrum, excellent conductivity, and strong photothermal effect. In this work, we explored for the first time the photothermal effect of PPy nanoparticles (PPy-NPs) in a photothermal-induced detector structure and developed a new type of air-stable hybrid PPy-NPs/Pt photodetector (PD) with NIR/SWIR sensitivity. By combining PPy-NPs with a platinum (Pt)-resistive pattern, we fabricated PPy-NPs/Pt PDs that are sensitive to illumination in the wavelength range from 800 to 2000 nm. Under the illumination of λ = 1.5 μm, the maximum photoresponsivity was measured to be ∼1.3 A/W with a 131 μs photoresponse rise time. Owing to the excellent material stability from both PPy-NPs and the Pt pattern, the current photodetectors show long-term stable photoresponsivity when they were stored in air without encapsulation. The results suggest that the PPy-NPs/Pt hybrid PDs are promising candidates for a new type of low-cost and broadband due to their multiple advantages such as free of toxic heavy metals, air stability, and solution processing.

Surface-engineered smart nanocarrier-based inhalation formulations for targeted lung cancer chemotherapy: a review of current practices

Lung cancer is the second most common and lethal cancer in the world. Chemotherapy is the preferred treatment modality for lung cancer and prolongs patient survival by effective controlling of tumor growth. However, owing to the nonspecific delivery of anticancer drugs, systemic chemotherapy has limited clinical efficacy and significant systemic adverse effects. Inhalation routes, on the other hand, allow for direct delivery of drugs to the lungs in high local concentrations, enhancing their anti-tumor activity with minimum side effects. Preliminary research studies have shown that inhaled chemotherapy may be tolerated with manageable adverse effects such as bronchospasm and cough. Enhancing the anticancer drugs deposition in tumor cells and limiting their distribution to other healthy cells will therefore increase their clinical efficacy and decrease their local and systemic toxicities. Because of the controlled release and localization of tumors, nanoparticle formulations are a viable option for the delivery of chemotherapeutics to lung cancers via inhalation. The respiratory tract physiology and lung clearance mechanisms are the key barriers to the effective deposition and preservation of inhaled nanoparticle formulations in the lungs. Designing and creating smart nanoformulations to optimize lung deposition, minimize pulmonary clearance, and improve cancerous tissue targeting have been the subject of recent research studies. This review focuses on recent examples of work in this area, along with the opportunities and challenges for the pulmonary delivery of smart nanoformulations to treat lung cancers.

A NIR-triggered multifunctional nanoplatform mediated by Hsp70 siRNA for chemo-hypothermal photothermal synergistic therapy

Recently, hypothermal photothermal therapy (HPTT) seemed essential for the future clinical transformation of cancer optical therapies. However, at a lower working temperature, heat shock proteins (HSPs) seriously affect the anti-tumor effect of HPTT. This work reports a reasonable design of a dual-responsive nanoplatform for the synergistic treatment of chemotherapy and HPTT. We adopted a one-step method to wrap indocyanine green (ICG) into imidazole skeleton-8 (ZIF-8) and further loaded it with the chemotherapy drug doxorubicin (DOX). Furthermore, we introduced Hsp-70 siRNA to block the affection of HSPs at an upstream node, thereby avoiding the side effects of traditional heat shock protein inhibitors. The prepared ZIF-8@ICG@DOX@siRNA nanoparticles (ZID-Si NPs) could significantly improve the stability of siRNA to effectively down-regulate the expression of HSP70 protein during the photothermal therapy, thus realizing the pH-controlled and NIR-triggered release of the chemotherapeutical drug DOX. Moreover, tumors were also imaged accurately by ICG wrapped in ZID-Si nanoparticles. After the evaluation of the in vitro and in vivo photothermal effect as well as the anti-tumor activity, we found that the added Hsp-70 siRNA enhanced the synergistic anti-cancer activity of HPTT and chemotherapy. In summary, this work holds great potential in cancer treatment, and suggests better efficacy of synergistic chemo/HPTT than the single-agent therapy.

All-purpose nanostrategy based on dose deposition enhancement, cell cycle arrest, DNA damage, and ROS production as prostate cancer radiosensitizer for potential clinical translation

Radiotherapy (RT) is one of the main treatments for men with prostate cancer (PCa). To date, numerous sophisticated nano-formulations as radiosensitizers have been synthesized with inspiring therapeutic effects both in vitro and in vivo; however, almost all the attention has been paid on the enhanced dose deposition effect by secondary electrons of nanomaterials with high atomic numbers (Z); despite this, cell-cycle arrest, DNA damage, and also reactive oxygen species (ROS) production are critical working mechanisms that account for radiosensitization. Herein, an 'all-purpose' nanostrategy based on dose deposition enhancement, cell cycle arrest, and ROS production as prostate cancer radiosensitizer for potential clinical translation was proposed. The rather simple structure of docetaxel-loaded Au nanoparticles (NPs) with prostate specific membrane antigen (PSMA) ligand conjugation have been successfully synthesized. Enhanced cellular uptake achieved via the selective internalization of the NPs by PCa cells with positive PSMA expression could guarantee enhanced dose deposition. Moreover, the as-synthesized nanosystem could effectively arrest the cell cycle at G2/M phases, which would reduce the ability of DNA damage repair for more irradiation sensitive of the PCa cells. Moreover, the G2/M phase arrest would further promote cascade retention and the enrichment of NPs within the cells. Furthermore, ROS generation and double strand breaks greatly promoted by NPs under irradiation (IR) could also provide an underlying basis for effective radiosensitizers. In vitro and in vivo investigations confirmed the as-synthesized NPs as an effective nano-radiosensitizer with ideal safety. More importantly, all moieties within the present nanosystem have been approved by FDA for the purpose of PCa treatment, thus making it highly attractive for clinical translation.

Magnetic systems for cancer immunotherapy

Immunotherapy is a rapidly developing area of cancer treatment due to its higher specificity and potential for greater efficacy than traditional therapies. Immune cell modulation through the administration of drugs, proteins, and cells can enhance antitumoral responses through pathways that may be otherwise inhibited in the presence of immunosuppressive tumors. Magnetic systems offer several advantages for improving the performance of immunotherapies, including increased spatiotemporal control over transport, release, and dosing of immunomodulatory drugs within the body, resulting in reduced off-target effects and improved efficacy. Compared to alternative methods for stimulating drug release such as light and pH, magnetic systems enable several distinct methods for programming immune responses. First, we discuss how magnetic hyperthermia can stimulate immune cells and trigger thermoresponsive drug release. Second, we summarize how magnetically targeted delivery of drug carriers can increase the accumulation of drugs in target sites. Third, we review how biomaterials can undergo magnetically driven structural changes to enable remote release of encapsulated drugs. Fourth, we describe the use of magnetic particles for targeted interactions with cellular receptors for promoting antitumor activity. Finally, we discuss translational considerations of these systems, such as toxicity, clinical compatibility, and future opportunities for improving cancer treatment.

Dextran-Curcumin Nanosystems Inhibit Cell Growth and Migration Regulating the Epithelial to Mesenchymal Transition in Prostate Cancer Cells

Functional nanocarriers which are able to simultaneously vectorize drugs to the site of interest and exert their own cytotoxic activity represent a significant breakthrough in the search for effective anticancer strategies with fewer side effects than conventional chemotherapeutics. Here, we propose previously developed, self-assembling dextran-curcumin nanoparticles for the treatment of prostate cancer in combination therapy with Doxorubicin (DOXO). Biological effectiveness was investigated by evaluating the cell viability in either cancer and normal cells, reactive oxygen species (ROS) production, apoptotic effect, interference with the cell cycle, and the ability to inhibit cell migration and reverse the epithelial to mesenchymal transition (EMT). The results proved a significant enhancement of curcumin efficiency upon immobilization in nanoparticles: IC50 reduced by a half, induction of apoptotic effect, and improved ROS production (from 67 to 134%) at low concentrations. Nanoparticles guaranteed a pH-dependent DOXO release, with a more efficient release in acidic environments. Finally, a synergistic effect between nanoparticles and Doxorubicin was demonstrated, with the free curcumin showing additive activity. Although in vivo studies are required to support the findings of this study, these preliminary in vitro data can be considered a proof of principle for the design of an effective therapy for prostate cancer treatment.