Hyaluronan-Stabilized Redox-Sensitive Nanoassembly for Chemo-Gene Therapy and Dual T1/T2 MR Imaging in Drug-Resistant Breast Cancer Cells.

Tailoring combinatorial therapies along with real-time monitoring strategies has been the major focus of overcoming multidrug resistance in cancer. However, attempting to develop a multifunctional nanoplatform in a single construct leads to compromising therapeutic outcomes. Herein, we developed a simple, theranostic nanoassembly containing a hyaluronic acid-stabilized redox-sensitive (HART) polyethylenimine polyplex composed of a doxorubicin (DOX) intercalated Bcl-2 shRNA encoded plasmid along with a green-synthesized hausmannite (Mn3O4) and hematite (Fe3O4) nanoparticle (GMF). The highly stable HART nanoassembly has enhanced CD44-mediated intracellular uptake along with hyaluronidase (hylase) and redox-responsive drug-gene release. With Bcl-2 gene silencing induced by the successful delivery of HART in multidrug-resistant MCF7 breast cancer cells, the synergistic cytotoxic effect of Bcl-2 silencing and DOX was achieved. In addition, the HART nanoassembly containing GMF exhibited excellent dual MRI contrast (T1/T2) by reducing artifact signals. Overall, the HART nanoassembly with its enhanced theranostic properties has the potential to improve the therapeutic efficacy in future preclinical and clinical trials.

Peroxidase-Mimicking Nanoassembly Mitigates Lipopolysaccharide-Induced Endotoxemia and Cognitive Damage in the Brain by Impeding Inflammatory Signaling in Macrophages.

Oxidative stress during sepsis pathogenesis remains the most-important factor creating imbalance and dysregulation in immune-cell function, usually observed following initial infection. Hydrogen peroxide (H2O2), a potentially toxic reactive oxygen species (ROS), is excessively produced by pro-inflammatory immune cells during the initial phases of sepsis and plays a dominant role in regulating the pathways associated with systemic inflammatory immune activation. In the present study, we constructed a peroxide scavenger mannosylated polymeric albumin manganese dioxide (mSPAM) nanoassembly to catalyze the decomposition of H2O2 responsible for the hyper-activation of pro-inflammatory immune cells. In a detailed manner, we investigated the role of mSPAM nanoassembly in modulating the expression and secretion of pro-inflammatory markers elevated in bacterial lipopolysaccharide (LPS)-mediated endotoxemia during sepsis. Through a facile one-step solution-phase approach, hydrophilic bovine serum albumin reduced manganese dioxide (BM) nanoparticles were synthesized and subsequently self-assembled with cationic mannosylated disulfide cross-linked polyethylenimine (mSP) to formulate mSPAM nanoassembly. In particular, we observed that the highly stable mSPAM nanoassembly suppressed HIF1α expression by scavenging H2O2 in LPS-induced macrophage cells. Initial investigation revealed that a significant reduction of free radicals by the treatment of mSPAM nanoassembly has reduced the infiltration of neutrophils and other leukocytes in a local endotoxemia animal model. Furthermore, therapeutic studies in a systemic endotoxemia model demonstrated that mSPAM treatment reduced TNF-α and IL-6 inflammatory cytokines in serum, in turn circumventing organ damage done by the inflammatory macrophages. Interestingly, we also observed that the reduction of these inflammatory cytokines by mSPAM nanoassembly further prevented IBA-1 immuno-positive microglial cell activation in the brain and consequently improved the cognitive function of the animals. Altogether, the administration of mSPAM nanoassembly scavenged H2O2 and suppressed HIF1α expression in LPS-stimulated macrophages and thereby inhibited the progression of local and systemic inflammation as well as neuroinflammation in an LPS-induced endotoxemia model. This mSPAM nanoassembly system could serve as a potent anti-inflammatory agent, and we further anticipate its successful application in treating various inflammation-related diseases.

Nanoparticle-Based Phototriggered Cancer Immunotherapy and Its Domino Effect in the Tumor Microenvironment.

Immune system evasion by cancer cells is one of the hallmarks of cancers, and it occurs with the support of tumor-associated immune cells (TICs) in the tumor microenvironment that increase the growth and invasiveness of tumor cells. With recent advancements in the development of novel near-infrared (NIR)-responsive nanoparticles, specifically eradicating TICs or inducing an inflammatory immune response by activating killer T cells has become possible. This review will discuss the mechanisms and applications of phototriggered immunotherapy in detail. In addition, various nanoparticles employed in phototriggered immunotherapy for cancer treatment will be covered. Furthermore, the challenges and future directions of phototriggered nanoparticle development for anticancer immunotherapy will be briefly discussed.

A Lipophilic IR-780 Dye-Encapsulated Zwitterionic Polymer-Lipid Micellar Nanoparticle for Enhanced Photothermal Therapy and NIR-Based Fluorescence Imaging in a Cervical Tumor Mouse Model.

To prolong blood circulation and avoid the triggering of immune responses, nanoparticles in the bloodstream require conjugation with polyethylene glycol (PEG). However, PEGylation hinders the interaction between the nanoparticles and the tumor cells and therefore limits the applications of PEGylated nanoparticles for therapeutic drug delivery. To overcome this limitation, zwitterionic materials can be used to enhance the systemic blood circulation and tumor-specific delivery of hydrophobic agents such as IR-780 iodide dye for photothermal therapy. Herein, we developed micellar nanoparticles using the amphiphilic homopolymer poly(12-(methacryloyloxy)dodecyl phosphorylcholine) (PCB-lipid) synthesized via reversible addition-fragmentation chain transfer (RAFT) polymerization. The PCB-lipid can self-assemble into micelles and encapsulate IR-780 dye (PCB-lipid-IR-780). Our results demonstrated that PCB-lipid-IR-780 nanoparticle (NP) exhibited low cytotoxicity and remarkable photothermal cytotoxicity to cervical cancer cells (TC-1) upon near-infrared (NIR) laser irradiation. The biodistribution of PCB-lipid-IR-780 showed higher accumulation of PCB-lipid-IR-780 than that of free IR-780 in the TC-1 tumor. Furthermore, following NIR laser irradiation of the tumor region, the PCB-lipid-IR-780 accumulated in the tumor facilitated enhanced tumor ablation and subsequent tumor regression in the TC-1 xenograft model. Hence, these zwitterionic polymer-lipid hybrid micellar nanoparticles show great potential for cancer theranostics and might be beneficial for clinical applications.

Targeted treatment of gouty arthritis by biomineralized metallic nanozyme-mediated oxidative stress-mitigating nanotherapy.

Gouty arthritis is characterized by chronic deposition of monosodium urate (MSU) crystals in the joints and other tissues, resulting in the production of excess reactive oxygen species (ROS) and proinflammatory cytokines that intensify synovial inflammation. This condition is mainly associated with inflammatory M1 macrophage activation and oxidative stress production. Hence, gout symptoms can often be resolved by eliminating M1 macrophage activation and scavenging oxidative stress in the inflamed areas. Herein, we developed M1-macrophage-targeting biomineralized metallic nanozymes (FALNZs) that deplete oxidative stress and reduce the M1 macrophage levels to mitigate gouty arthritis. Intra-articular injection of the FALNZs targets inflammatory macrophages and suppresses ROS levels in joints with MSU-crystal-induced arthritis. In addition, the FALNZs alleviate joint swelling, inflammatory cytokine production, and pathological features of the joints. Overall, the proposed therapeutic approach is biocompatible and is an effective ROS scavenger for the treatment of gouty pathogenesis.

Mechanism of Action of Oxazoline-Based Antimicrobial Polymers Against Staphylococcus aureus: In Vivo Antimicrobial Activity Evaluation.

Antimicrobial-resistant pathogens have reached alarming levels, becoming one of the most pressing global health issues. Hence, new treatments are necessary for the fight against antimicrobial resistance. Synthetic nanoengineered antimicrobial polymers (SNAPs) have emerged as a promising alternative to antimicrobial peptides, overcoming some of their limitations while keeping their key features. Herein, a library of amphiphilic oxazoline-based SNAPs using cationic ring-opening polymerization (CROP) is designed. Amphipathic compounds with 70% cationic content exhibit the highest activity against clinically relevant Staphylococcus aureus isolates, maintaining good biocompatibility in vitro and in vivo. The mechanism of action of the lead compounds against S. aureus is assessed using various microscopy techniques, indicating cell membrane disruption, while the cell wall remains unaffected. Furthermore, a potential interaction of the compounds with bacterial DNA is shown, with possible implications on bacterial division. Finally, one of the compounds exhibits high efficacy in vivo in an insect infection model.

Biomineralized Nanoscavenger Abrogates Proinflammatory Macrophage Polarization and Induces Neutrophil Clearance through Reverse Migration during Gouty Arthritis.

The deposition of monosodium urate (MSU) crystals induces the overexpression of reactive oxygen species (ROS) and proinflammatory cytokines in residential macrophages, further promoting the infiltration of inflammatory leukocytes in the joints of gouty arthritis. Herein, a peroxidase-mimicking nanoscavenger was developed by forming manganese dioxide over albumin nanoparticles loaded with an anti-inflammatory drug, indomethacin (BIM), to block the secretion of ROS and COX2-induced proinflammatory cytokines in the MSU-induced gouty arthritis model. In the MSU-induced arthritis mouse model, the BIM nanoparticles alleviated joint swelling, which is attributed to the abrogation of ROS and inflammatory cytokine secretions from proinflammatory macrophages that induces neutrophil infiltration and fluid building up in the inflammation site. Further, the BIM nanoparticle treatment reduced the influx of macrophages and neutrophils in the injured region by blocking migration and inducing reverse migration in the zebrafish larva tail amputation model as well as in MSU-induced peritonitis and air pouch mouse models. Overall, the current strategy of employing biomineralized nanoscavengers for arthritis demonstrates clinical significance in dual blocking of peroxides and COX2 to prevent influx of inflammatory cells into the sites of inflammation.

Thermosusceptible Nitric-Oxide-Releasing Nitrogel for Strengthening Antitumor Immune Responses with Tumor Collagen Diminution and Deep Tissue Delivery during NIR Laser-Assisted Photoimmunotherapy.

Combined cancer immunotherapy has demonstrated promising potential with an amplified antitumor response and immunosuppressive tumor microenvironment (TME) modulation. However, one of the main issues that cause treatment failure is the poor diffusion and insufficient penetration of therapeutic and immunomodulatory agents in solid tumors. Herein, a cancer treatment approach that combines photothermal therapy (PTT) and nitric oxide (NO) gas therapy for tumor extracellular matrix (ECM) degradation, along with NLG919, an indoleamine 2,3-dioxygenase (IDO) inhibitor that reduces tryptophan catabolism to kynurenine, and DMXAA, a stimulator of interferon gene (STING) agonist that stimulates antigen cross-presentation, is proposed to overcome this issue. Upon NIR (808 nm) laser irradiation, NO-GEL achieved the desired thermal ablation by releasing sufficient tumor antigens through immunogenic cell death (ICD). NO delivery triggered local diffusion of excess NO gas for effectively degrading tumor collagen in the ECM, homogeneously delivered NLG919 throughout the tumor tissue, inhibited IDO expression that was upregulated by PTT, and reduced the immune suppressive activities. The sustained release of DMXAA prolonged dendritic cell maturation and CD8+ T cell activation against the tumor. In summary, NO-GEL therapeutics offer a significant tumor regression with PTT and STING agonist combination that stimulates a durable antitumor immune response. Additional unification of IDO inhibition during PTT supplements the immunotherapy by reducing the T cell apoptosis and immune suppressive cell infiltration to TME. NO-GEL with the STING agonist and IDO inhibitor is an effective therapeutic combination to counter possible limitations during solid tumor immunotherapy.

A sugar modified amphiphilic cationic nano-adjuvant ceased tumor immune suppression and rejuvenated peptide vaccine induced antitumor immunity in cervical cancer.

Human papilloma virus (HPV), one of the most common cancer-causing viruses, accounts for more than 90% of human anal and cervical cancers. Clinical studies have focused on adjuvant therapy with vaccines to improve therapeutic outcomes in patients with late-stage HPV-related cancers. In the present study, a mannose receptor (CD206) targeting a lithocholic acid-modified polyethylenimine (PEI) nano-adjuvant delivering the toll-like receptor 7/8 agonist, resiquimod (R848) (mLAPMi-R848), in a HPV E6- and E7-expressing TC-1 tumor murine model was developed. Peritumoral administration of mLAPMi resulted in enhanced accumulation in tumor/tumor-draining lymph nodes and significantly targeted antigen presenting cells like macrophage and dendritic cells. PEI-based nanocarriers can exploit the adjuvant potency of R848 and improve the antitumor immunity. Hence, co-administration of mLAPMi-R848 along with an E6E7 peptide in TC-1 tumor mice eradicated tumor burden and elicited splenocyte-induced cytotoxicity in TC-1 cancer cells. In a bilateral TC-1 tumor model, administration of mLAPMi-R848 and E6E7 peptide significantly suppressed both primary and secondary tumor burdens and improved the overall survival rate. Immune cell profiling revealed elevated levels of mature DCs and CD8+ T cells but reduced levels of tumor-associated immunosuppressive cells (TAICs) like myeloid derived suppressor cells (MDSCs) and regulatory T (Treg) cells in distal tumors. Overall, this study demonstrated that mLAPMi-R848 has improved the antitumor immunity of the peptide antigen against HPV-induced cancers by targeted immunodulation of antigen presenting cells (APCs) and reducing TAICs. Furthermore, this nano-adjuvant has the potential to offer a new treatment option for patients with cervical cancer and can be applied for the treatment of other HPV induced cancers.

Hyaluronan-coated Prussian blue nanoparticles relieve LPS-induced peritonitis by suppressing oxidative species generation in tissue-resident macrophages.

Excessive inflammatory response during sepsis causes irreversible damage to healthy tissues and results in multi-organ failure. During infection, bacterial endotoxin-triggered inflammatory responses in macrophages facilitate the recruitment of circulating leukocytes, including neutrophils and monocytes. A key component that aggravates the systemic inflammatory response is the generation of stable reactive oxygen species such as hydrogen peroxide (H2O2). In this study, we present a versatile strategy to reduce the activation of tissue-resident macrophages and prevent leukocyte infiltration in an LPS-induced endotoxemia model. We designed and synthesized hyaluronic acid-stabilized Prussian blue (HAPB) nanoparticles and validated their activity in the dismutation of H2O2 in LPS-induced tissue-resident macrophages. Hyaluronic acid provided stability and enhanced the intracellular uptake of insoluble Prussian blue via the CD44 receptor on LPS-activated macrophages. Following HAPB administration to an LPS-induced peritonitis murine model, the level of M1 inflammatory macrophage population decreased, and the infiltration of neutrophils along with monocytes was suppressed. Overall, we have developed biocompatible Prussian blue nanoparticles to ameliorate inflammatory stress in LPS-induced endotoxemia by scavenging the intracellular peroxide thereby inhibiting inflammatory cascade in tissue-resident macrophages. Therefore, HAPB nanoparticles may potentially be used as novel nano-stress relievers in sepsis. The nanomaterials may have clinical application in sepsis and in other inflammatory diseases involving peroxides as key inflammatory agents.

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.

Dual-stimuli-responsive albumin-polyplex nanoassembly for spatially controlled gene release in metastatic breast cancer.

Stimuli-responsive polymeric nanoparticles are useful for overcoming challenges such as transfection efficiency and the specific and safe delivery of genes to cancer cells. Transfection outcomes can be improved through spatially and temporally controlled gene release. We formulated a nanoassembly comprising a disulfide-crosslinked polyethylenimine (ssPEI) conjugated with a tumor-specific cell-penetrating peptide (DS 4-3) (SPD) polyplex and bovine serum albumin (BSA)-loaded IR780 (BI) nanoparticle, thereby forming a dual-stimulus-triggered, tumor-penetrating and gene-carrying nanoassembly (BI-SPD) via electrostatic complexing. BI-SPD nanoassembly were composed of highly stable nanosized complexes with an average size of 457 ±â€¯27.5 nm, exhibiting an up to two-fold enhanced transfection efficiency with no sign of potential cytotoxicity in breast cancer cells. Moreover, upon laser irradiation, a four-fold increase in transfection efficiency was achieved due to the rapid endosomal escape of polyplexes triggered by the local heat induced by the BI-SPD nanoassembly. Additionally, the high redox environment in tumor cells facilitated the disassembly of the SPD polyplex for efficient plasmid release in the cytosol. The BI-SPD nanoassembly also exhibited high penetration and enhanced photothermally triggered gene expression in the 4T1 spheroid model. This BI-SPD nanoassembly has the potential to enhance the expression of therapeutic genes in tumor models without causing significant toxicity to surrounding healthy tissues, since it has shown higher tumor targeting and accumulation in the 4T1 tumor in mice model.

Self-Assembled, Adjuvant/Antigen-Based Nanovaccine Mediates Anti-Tumor Immune Response against Melanoma Tumor.

Malignant melanoma is a highly aggressive type of cancer that requires radical treatment strategies to inhibit the cancer cell progression and metastasis. In recent years, preclinical research and clinical trials on melanoma treatment have been considerably focused on the adjuvant-based immunotherapy for enhancing the immune response of innate immune cells against cancer cells. However, the clinical outcome of these adjuvant-based treatments is inadequate due to an improper delivery system for these immune activators to reach the target site. Hence, we developed a vaccine formulation containing tumor lysate protein (TL) and poly I:C (PIC) complexed with positively charged poly (sorbitol-co-polyethylenimine (PEI) (PSPEI). The resulting ionic PSPEI-polyplexed antigen/adjuvant (PAA) (PSPEI-PAA) nanocomplexes were stable at the physiological condition, are non-toxic, and have enhanced intracellular uptake of antigen and adjuvant in immature dendritic cells leading to dendritic cell maturation. In the murine B16F10 tumor xenograft model, PSPEI-PAA nanocomplexes significantly suppressed tumor growth and did not exhibit any noticeable sign of toxicity. The level of matured dendritic cells (CD80+/CD86+ cells) in the tumor draining lymph node of PSPEI-PAA treated tumor mice were enhanced and therefore CD8+ T cells infiltration in the tumor were enriched. Additionally, the cytotoxic T lymphocytes (CTLs) assay involving co-culturing of splenocytes isolated from the PSPEI-PAA-treated mice with that of B16F10 cells significantly revealed enhanced cancer killing by the TL-reactivated CTLs compared to untreated control mice bearing tumor. Therefore, we strongly believe that PSPEI-PAA nanocomplexes could be an efficient antigen/adjuvant delivery system and enhance the antitumor immune response against melanoma tumor in the future clinical trials.

Trigger-Responsive Gene Transporters for Anticancer Therapy.

In the current era of gene delivery, trigger-responsive nanoparticles for the delivery of exogenous nucleic acids, such as plasmid DNA (pDNA), mRNA, siRNAs, and miRNAs, to cancer cells have attracted considerable interest. The cationic gene transporters commonly used are typically in the form of polyplexes, lipoplexes or mixtures of both, and their gene transfer efficiency in cancer cells depends on several factors, such as cell binding, intracellular trafficking, buffering capacity for endosomal escape, DNA unpacking, nuclear transportation, cell viability, and DNA protection against nucleases. Some of these factors influence other factors adversely, and therefore, it is of critical importance that these factors are balanced. Recently, with the advancements in contemporary tools and techniques, trigger-responsive nanoparticles with the potential to overcome their intrinsic drawbacks have been developed. This review summarizes the mechanisms and limitations of cationic gene transporters. In addition, it covers various triggers, such as light, enzymes, magnetic fields, and ultrasound (US), used to enhance the gene transfer efficiency of trigger-responsive gene transporters in cancer cells. Furthermore, the challenges associated with and future directions in developing trigger-responsive gene transporters for anticancer therapy are discussed briefly.