Combination of MHI148 Targeted Photodynamic Therapy and STING Activation Inhibits Tumor Metastasis and Recurrence.

Metastasis and recurrence are notable contributors to mortality associated with breast cancer. Although immunotherapy has shown promise in mitigating these risks after conventional treatments, its effectiveness remains constrained by significant challenges, such as impaired antigen presentation by dendritic cells (DCs) and inadequate T cell infiltration into tumor tissues. To address these limitations, we developed a multifunctional nanoparticle platform, termed GM@P, which consisted of a hydrophobic shell encapsulating the photosensitizer MHI148 and a hydrophilic core containing the STING agonist 2'3'-cGAMP. This design elicited robust type I interferon responses to activate antitumor immunity. The GM@P nanoparticles loaded with MHI148 specifically targeted breast cancer cells. Upon exposure to 808 nm laser irradiation, the MHI148-loaded nanoparticles produced toxic reactive oxygen species (ROS) to eradicate tumor cells through photodynamic therapy (PDT). Notably, PDT stimulated immunogenic cell death (ICD) to foster the potency of antitumor immune responses. Furthermore, the superior photoacoustic imaging (PAI) capabilities of MHI148 enabled the simultaneous visualization of diagnostic and therapeutic procedures. Collectively, our findings uncovered that the combination of PDT and STING activation facilitated a more conducive immune microenvironment, characterized by enhanced DC maturation, infiltration of CD8+ T cells, and proinflammatory cytokine release. This strategy stimulated local immune responses to augment systemic antitumor effects, offering a promising approach to suppress tumor growth, inhibit metastasis, and prevent recurrence.

Nitric oxide nano-reactor DNMF/PLGA enables tumor vascular microenvironment and chemo-hyperthermia synergetic therapy.

BACKGROUND: Breast cancer ranks first among malignant tumors, of which triple-negative breast cancer (TNBC) is characterized by its highly invasive behavior and the worst prognosis. Timely diagnosis and precise treatment of TNBC are substantially challenging. Abnormal tumor vessels play a crucial role in TNBC progression and treatment. Nitric oxide (NO) regulates angiogenesis and maintains vascular homeostasis, while effective NO delivery can normalize the tumor vasculature. Accordingly, we have proposed here a tumor vascular microenvironment remodeling strategy based on NO-induced vessel normalization and extracellular matrix collagen degradation with multimodality imaging-guided nanoparticles against TNBC called DNMF/PLGA. RESULTS: Nanoparticles were synthesized using a chemotherapeutic agent doxorubicin (DOX), a NO donor L-arginine (L-Arg), ultrasmall spinel ferrites (MnFe2O4), and a poly (lactic-co-glycolic acid) (PLGA) shell. Nanoparticle distribution in the tumor was accurately monitored in real-time through highly enhanced magnetic resonance imaging and photoacoustic imaging. Near-infrared irradiation of tumor cells revealed that MnFe2O4 catalyzes the production of a large amount of reactive oxygen species (ROS) from H2O2, resulting in a cascade catalysis of L-Arg to trigger NO production in the presence of ROS. In addition, DOX activates niacinamide adenine dinucleotide phosphate oxidase to generate and supply H2O2. The generated NO improves the vascular endothelial cell integrity and pericellular contractility to promote vessel normalization and induces the activation of endogenous matrix metalloproteinases (mainly MMP-1 and MMP-2) so as to promote extravascular collagen degradation, thereby providing an auxiliary mechanism for efficient nanoparticle delivery and DOX penetration. Moreover, the chemotherapeutic effect of DOX and the photothermal effect of MnFe2O4 served as a chemo-hyperthermia synergistic therapy against TNBC. CONCLUSION: The two therapeutic mechanisms, along with an auxiliary mechanism, were perfectly combined to enhance the therapeutic effects. Briefly, multimodality image-guided nanoparticles provide a reliable strategy for the potential application in the fight against TNBC.

Smart responsive Fe/Mn nanovaccine triggers liver cancer immunotherapy via pyroptosis and pyroptosis-boosted cGAS-STING activation.

BACKGROUND: The prognosis for hepatocellular carcinoma (HCC) remains suboptimal, characterized by high recurrence and metastasis rates. Although metalloimmunotherapy has shown potential in combating tumor proliferation, recurrence and metastasis, current apoptosis-based metalloimmunotherapy fails to elicit sufficient immune response for HCC. RESULTS: A smart responsive bimetallic nanovaccine was constructed to induce immunogenic cell death (ICD) through pyroptosis and enhance the efficacy of the cGAS-STING pathway. The nanovaccine was composed of manganese-doped mesoporous silica as a carrier, loaded with sorafenib (SOR) and modified with MIL-100 (Fe), where Fe3+, SOR, and Mn2+ were synchronized and released into the tumor with the help of the tumor microenvironment (TME). Afterward, Fe3+ worked synergistically with SOR-induced immunogenic pyroptosis (via both the classical and nonclassical signaling pathways), causing the outflow of abundant immunogenic factors, which contributes to dendritic cell (DC) maturation, and the exposure of double-stranded DNA (dsDNA). Subsequently, the exposed dsDNA and Mn2+ jointly activated the cGAS-STING pathway and induced the release of type I interferons, which further led to DC maturation. Moreover, Mn2+-related T1 magnetic resonance imaging (MRI) was used to visually evaluate the smart response functionality of the nanovaccine. CONCLUSION: The utilization of metallic nanovaccines to induce pyroptosis-mediated immune activation provides a promising paradigm for HCC treatment.

Self-Reinforced Bimetallic Mito-Jammer for Ca2+ Overload-Mediated Cascade Mitochondrial Damage for Cancer Cuproptosis Sensitization.

Overproduction of reactive oxygen species (ROS), metal ion accumulation, and tricarboxylic acid cycle collapse are crucial factors in mitochondria-mediated cell death. However, the highly adaptive nature and damage-repair capabilities of malignant tumors strongly limit the efficacy of treatments based on a single treatment mode. To address this challenge, a self-reinforced bimetallic Mito-Jammer is developed by incorporating doxorubicin (DOX) and calcium peroxide (CaO2) into hyaluronic acid (HA) -modified metal-organic frameworks (MOF). After cellular, Mito-Jammer dissociates into CaO2 and Cu2+ in the tumor microenvironment. The exposed CaO2 further yields hydrogen peroxide (H2O2) and Ca2+ in a weakly acidic environment to strengthen the Cu2+-based Fenton-like reaction. Furthermore, the combination of chemodynamic therapy and Ca2+ overload exacerbates ROS storms and mitochondrial damage, resulting in the downregulation of intracellular adenosine triphosphate (ATP) levels and blocking of Cu-ATPase to sensitize cuproptosis. This multilevel interaction strategy also activates robust immunogenic cell death and suppresses tumor metastasis simultaneously. This study presents a multivariate model for revolutionizing mitochondria damage, relying on the continuous retention of bimetallic ions to boost cuproptosis/immunotherapy in cancer.

Decomposable Nanoagonists Enable NIR-Elicited cGAS-STING Activation for Tandem-Amplified Photodynamic-Metalloimmunotherapy.

Activation of the cyclic GMP-AMP synthase-stimulator of interferon genes (cGAS-STING) pathway has emerged as an efficient strategy to improve the therapeutic outcomes of immunotherapy. However, the "constantly active" mode of current STING agonist delivery strategies typically leads to off-target toxicity and hyperimmunity. To address this critical issue, herein a metal-organic frameworks-based nanoagonist (DZ@A7) featuring tumor-specific and near-infrared (NIR) light-enhanced decomposition is constructed for precisely localized STING activation and photodynamic-metalloimmunotherapy. The engineered nanoagonist enabled the generation of mitochondria-targeted reactive oxygen species under NIR irradiation to specifically release mitochondrial DNA (mtDNA) and inhibit the repair of nuclear DNA via hypoxia-responsive drugs. Oxidized tumor mtDNA serves as an endogenous danger-associated molecular pattern that activates the cGAS-STING pathway. Concurrently, NIR-accelerated zinc ions overloading in cancer cells further enhance the cGAS enzymatic activity through metalloimmune effects. By combining the synergistically enhanced activation of the cGAS-STING pathway triggered by NIR irradiation, the engineered nanoagonist facilitated the maturation of dendritic cells and infiltration of cytotoxic T lymphocytes for primary tumor eradication, which also established a long-term anti-tumor immunity to suppress tumor metastasis. Therefore, the developed nanoagonist enabled NIR-triggered, agonist-free, and tandem-amplified activation of the cGAS-STING pathway, thereby offering a distinct paradigm for photodynamic-metalloimmunotherapy.

NIR Activated Multimodal Therapeutics Based on Metal-Phenolic Networks-Functionalized Nanoplatform for Combating against Multidrug Resistance and Metastasis.

Multidrug resistance (MDR) and metastasis in cancer have become increasingly serious problems since antitumor efficiency is greatly restricted by a single therapeutic modality and the insensitive tumor microenvironment (TME). Herein, metal-phenolic network-functionalized nanoparticles (t-P@TFP NPs) are designed to realize multiple therapeutic modalities and reshape the TME from insensitive to sensitive under multimodal imaging monitoring. After a single irradiation, a near-infrared laser-activated multistage reaction occurs. t-P@TFP NPs trigger the phase transition of perfluoropentane (PFP) to release tannic acid (TA)/ferric ion (Fe3+ )-coated paclitaxel (PTX) and cause hyperthermia in the tumor region to efficiently kill cancer cells. Additionally, PTX is released after the disassembly of the TA-Fe3+ film by the abundant adenosine triphosphate (ATP) in the malignant tumor, which concurrently inhibits ATP-dependent drug efflux to improve sensitivity to chemotherapeutic agents. Furthermore, hyperthermia-induced immunogenic cell death (ICD) transforms "cold" tumors into "hot" tumors with the assistance of PD-1/PD-L1 blockade to evoke antitumor immunogenicity. This work carefully reveals the mechanisms underlying the abilities of these multifunctional NPs, providing new insights into combating the proliferation and metastasis of multidrug-resistant tumors.

Nanoenabled Tumor Energy Metabolism Disorder via Sonodynamic Therapy for Multidrug Resistance Reversal and Metastasis Inhibition.

Cancer multidrug resistance (MDR) is an important reason that results in chemotherapy failure. As a main mechanism of MDR, overexpressed P-glycoprotein (P-gp) utilizes adenosine triphosphate (ATP) to actively pump chemotherapy drugs out of cells. In addition, metabolic reprogramming of drug-resistant tumor cells (DRTCs) exacerbates the specific hypoxic microenvironment and promotes tumor metastasis and recurrence. Therefore, we propose a novel sonodynamic therapy (SDT) paradigm to induce energy metabolism disorder and drug resistance change of DRTCs. A US-controlled "Nanoenabled Energy Metabolism Jammer" (TL@HPN) is designed using perfluoropentane (PFP) adsorbing oxygen in the core, and a targeting peptide (CGNKRTR) is attached to the liposome as the delivery carrier shell to incorporate hematoporphyrin monomethyl ether (HMME) and paclitaxel (PTX). The TL@HPN with ultrasonic/photoacoustic imaging (PAI/USI) precisely controlled the release of drugs and oxygen after being triggered by ultrasound (US), which attenuated the hypoxic microenvironment. SDT boosted the reactive oxygen species (ROS) content in tumor tissues, preferentially inducing mitochondrial apoptosis and maximizing immunogenic cell death (ICD). Persistently elevated oxidative stress levels inhibited ATP production and downregulated P-gp expression by disrupting the redox balance and electron transfer of the respiratory chain. We varied the effect of TL@HPN combined with PD-1/PD-L1 to activate autoimmunity and inhibit tumor metastasis, providing a practical strategy for expanding the use of SDT-mediated tumor energy metabolism.