Heavy-Atom-Modulated Supramolecular Assembly Increases Antitumor Potency against Malignant Breast Tumors via Tunable Cooperativity

PEGylated BODIPY Photosensitizer for Type I Dominant Photodynamic Therapy and Afterglow Imaging

Type I photodynamic therapy (PDT) exhibits outstanding therapeutic effects in hypoxic environments in tumors, but the design of type I photosensitizers (PSs), especially those with simple structures but dramatic properties, remains a challenge. Herein, we report a design strategy for developing type I PSs in one molecule with afterglow luminescence. As a proof concept, a 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY) PS (BIP) bearing water-soluble poly(ethylene glycol) (mPEG550) chains is synthesized, and BIP can self-assemble into nanoparticles (BIPNs). Interestingly, BIPNs exhibit an O2•--triggered afterglow luminescence, which is scarce, especially for BODIPY derivatives. BIPNs demonstrate outstanding type I dominant PDT at an ultralow dose under both hypoxic and normoxic environments, which can significantly inhibit tumor growth under irradiation. This work highlights a high-performance PS with afterglow luminescence and excellent PDT effects, underscoring the significant potential of versatile PSs in clinical tumor theranostics.

Dissecting Exciton Dynamics in pH-Activatable Long-Wavelength Photosensitizers for Traceable Photodynamic Therapy

Tumor-specific activatable long-wavelength (LW) photosensitizers (PSs) show promise in overcoming the limitations of traditional photodynamic therapy (PDT), such as systemic phototoxicity and shallow tissue penetration. However, their insufficient LW light absorption and low singlet oxygen quantum yield (Φ 1O2) usually require high laser power density to produce thermal energy and synergistically enhance PDT. The strong photothermal radiation causing acute pain significantly reduces patient compliance and hinders the broader clinical application of LW PDT. Through the exciton dynamics dissection strategy, we have developed a series of pH-activatable cyanine-based LW PSs (LET-R, R = H, Cl, Br, I), among which the activated LET-I exhibits strong light absorption at 808 nm and a remarkable 3.2-fold enhancement in Φ 1O2 compared to indocyanine green. Transient spectroscopic analysis and theoretical calculations confirmed its significantly promoted intersystem crossing and simultaneously enhanced LW fluorescence emission characteristics. These features enable the activatable fluorescence and photoacoustic dual-modal imaging-escorted complete photodynamic eradication of tumors by the folic acid (FA)-modified LET-I probe (LET-I-FA), under the ultralow 808 nm laser power density (0.2 W cm-2) for irradiation, without the need for photothermal energy synergy. This research presents a novel strategy of dissecting exciton dynamics to screen activatable LW PSs for traceable PDT.

Facilely Achieving Near-Infrared-II J-Aggregates through Molecular Bending on a Donor-Acceptor Fluorophore for High-Performance Tumor Phototheranostics

Constructing J-aggregated organic dyes represents a promising strategy for obtaining biomedical second near-infrared (NIR-II) emissive materials, as they exhibit red-shifted spectroscopic properties upon assembly into nanoparticles (NPs) in aqueous environments. However, currently available NIR-II J-aggregates primarily rely on specific molecular backbones with intricate design strategies and are susceptible to fluorescence quenching during assembly. A facile approach for constructing bright NIR-II J-aggregates using prevalent donor-acceptor (D-A) molecules is still lacking. In this study, we present a facile method that transforms D-A molecules into J-aggregates by simply bending the molecule through introducing a methyl group, enabling high-performance NIR-II phototheranostics. The TAA-BT-CN molecule exhibits hypsochromic-shift absorption upon forming H-aggregated NPs, while the designed mTAA-BT-CN with a bent structure demonstrates a bathochromic shift of over 100 nm in absorption upon forming J-aggregated NPs, leading to much enhanced NIR-II emission beyond 1100 nm. With respect to its H-aggregated counterpart with the aggregation-caused quenching (ACQ) phenomenon, the J-aggregated mTAA-BT-CN NPs exhibit a 7-fold increase in NIR-II fluorescence owing to their aggregation-induced emission (AIE) property as well as efficient generation of heat and reactive oxygen species under 808 nm light excitation. Finally, the mTAA-BT-CN NPs are employed for whole-body blood vessel imaging using NIR-II technology as well as imaging-guided tumor phototherapies. This study will facilitate the flourishing advancement of J-aggregates based on prevalent D-A-type molecules.

Glutathione-Depleted Photodynamic Nanoadjuvant for Triggering Nonferrous Ferroptosis to Amplify Radiotherapy of Breast Cancer

Radiotherapy plays a crucial role in the treatment of advanced breast cancer, but the increased antioxidant system, especially the rise in glutathione (GSH), presents a significant obstacle to its effectiveness. To address this challenge, a versatile GSH-depleted photodynamic nanoadjuvant is developed to augment the efficacy of radiotherapy for breast cancer treatment. This nanoadjuvant operates within the tumor microenvironment to effectively deplete intracellular GSH through a sequence of cascaded processes, including GSH exhaustion, biosynthetic inhibition, and photodynamic oxidation. This leads to a notable accumulation of lipid peroxides (LPO) and subsequent suppression of glutathione peroxidase 4 (GPX4) activity. Consequently, the combined GSH depletion induced by the nanoadjuvant markedly promotes nonferrous ferroptosis, thereby contributing to the augmentation of antitumor efficiency during radiotherapy in breast cancer. This work presents an innovative approach to designing and synthesizing biocompatible nanoadjuvants with the goal of improving the efficacy of radiotherapy for breast cancer in prospective clinical scenarios.

Polymorphic Supramolecular Therapeutic Platforms with Precise Dye/Drug Ratio to Perform Synergistic Chemo-Photo Anti-Tumor Therapy and Long-Term Immune Protection

Malignant tumor has become one of the hellish killers threatening the health of people around the world, its diagnosis and treatment has become the concerns of public. However, the optimal therapeutic dose, undesired side-effect, and long-term immune activation were key and bottleneck problems in tumor treatment. Herein, different batches of supramolecular therapeutic platforms, including vesicles, spherical nanoparticles, and cylindrical nanorods, with precise ratios of dye to drug (1:2) and multiple stimulus responsiveness were constructed by host-guest complexation between cyanine-camptothecin conjugates (IR780-CPT2) and β-cyclodextrin (β-CD) pendent hydrophilic copolymers. The reduction responsiveness, near-infrared photothermal conversion and singlet oxygen (1O2) generation performances endowed these platforms excellent cancer cells killing effect in both of in vitro cellular experiments and in vivo mice models. More importantly, without affecting the weight of mice, the maturation of dendritic cells, proliferation of T cells, up-regulation of high mobility group protein B1, and reduction of immunosuppressive regulatory T cells were detected after employing a synergistic chemo-photo therapy, demonstrating the body's immune effect was successfully activated. Thus, during the treatment of primary tumor, the distal tumor was also inhibited. We believe this work could provide a distinctive way to fabricate supramolecular theranostic platforms with different morphologies and improve antitumor and antimetastasis capabilities.

A Photoactivatable Self-Assembled Nanoagonist for Synergistic Therapy against Pancreatic Ductal Adenocarcinoma

Immunotherapy has revolutionized the cancer treatment paradigm, yet efficient immunotherapeutic responses against immune-cold/desert cancers remain challenging. Herein, we report that photoactivatable nanoagonists yield a potent antitumor synergy of photoimmunotherapy against pancreatic ductal adenocarcinoma (PDAC). The nanoagonist was fabricated by assembling an amphiphilic boron dipyrromethene-derived polymer conjugated with a Toll-like receptor agonist via a photocleavable linker and stimulator of interferon genes agonist. The nanoagonist enables light-induced generation of reactive oxygen species and on-demand release of the agonists to yield synergistic photoimmunotherapy. The produced tumor antigens promote dendritic cell maturation, which is further amplified by these agonists for eliciting adaptive immunity, accompanied by apparently abscopal and long-term memory effects. The nanoagonist further alleviates the fibrosis of tumor stroma and the immunosuppressive microenvironment, leading to the deep infiltrations of clinically used therapeutics and immune cells to yield preferable combinational treatments against PDAC models. These results provide valuable insights into activatable nanoparticles for cancer therapy against immune-desert cancers.

Temperature-Responsive "Nano-to-Micro" Transformed Polymersomes for Enhanced Ultrasound/Fluorescence Dual Imaging-Guided Tumor Phototherapy

The perfect integration of microbubbles for efficient ultrasound imaging and nanocarriers for intelligent tumor-targeting delivery remains a challenge in precise tumor theranostics. Herein, we exquisitely fabricated laser-activated and targeted polymersomes (abbreviated as FIP-NPs) for simultaneously encapsulating the photosensitizer indocyanine green (ICG) and the phase change agent perfluorohexane (PFH). The formulated FIP-NPs were nanosize and effectively accumulated into tumors as observed by ICG fluorescence imaging. When the temperature rose above 56 °C, the encapsulated PFH transformed from liquid to gas and the FIP-NPs underwent balloon-like enlargement without structure destruction. Impressively, the enlarged FIP-NPs fused with adjacent polymersomes to form even larger microparticles. This temperature-responsive "nano-to-micro" transformation and fusion process was clearly demonstrated, and FIP-NPs showed greatly improved ultrasound signals. More importantly, FIP-NPs achieved dramatic antitumor efficacy through ICG-mediated phototherapy. Taken together, the novel polymersomes achieved excellent ultrasound/fluorescence dual imaging-guided tumor phototherapy, providing an optimistic candidate for the application of tumor theranostics.

Easy but Efficient: Facile Approach to Molecule with Theoretically Justified Donor-Acceptor Structure for Effective Photothermal Conversion and Intravenous Photothermal Therapy

To accelerate the pace in the field of photothermal therapy (PTT), it is urged to develop easily accessible photothermal agents (PTAs) showing high photothermal conversion efficiency (PCE). As a proof-of-concept, hereby a conventional strategy is presented to prepare donor-acceptor (D-A) structured PTAs through cycloaddition-retroelectrocyclization (CA-RE) reaction, and the resultant PTAs give high PCE upon near-infrared (NIR) irradiation. By joint experimental-theoretical study, these PTAs exhibit prominent D-A structure with strong intramolecular charge transfer (ICT) characteristics and significantly twisting between D and A units which account for the high PCEs. Among them, the DMA-TCNQ exhibits the strongest absorption in NIR range as well as the highest PCE of 91.3% upon irradiation by 760-nm LED lamp (1.2 W cm-2). In vitro and in vivo experimental results revealed that DMA-TCNQ exhibits low dark toxicity and high phototoxicity after IR irradiation along with nude mice tumor inhibition up to 81.0% through intravenous therapy. The findings demonstrate CA-RE reaction as a convenient approach to obtain twisted D-A structured PTAs for effective PTT and probably promote the progress of cancer therapies.

Nanocarriers address intracellular barriers for efficient drug delivery, overcoming drug resistance, subcellular targeting and controlled release

The cellular barriers are major bottlenecks for bioactive compounds entering into cells to accomplish their biological functions, which limits their biomedical applications. Nanocarriers have demonstrated high potential and benefits for encapsulating bioactive compounds and efficiently delivering them into target cells by overcoming a cascade of intracellular barriers to achieve desirable therapeutic and diagnostic effects. In this review, we introduce the cellular barriers ahead of drug delivery and nanocarriers, as well as summarize recent advances and strategies of nanocarriers for increasing internalization with cells, promoting intracellular trafficking, overcoming drug resistance, targeting subcellular locations and controlled drug release. Lastly, the future perspectives of nanocarriers for intracellular drug delivery are discussed, which mainly focus on potential challenges and future directions. Our review presents an overview of intracellular drug delivery by nanocarriers, which may encourage the future development of nanocarriers for efficient and precision drug delivery into a wide range of cells and subcellular targets.

Advances in Electrochemical Biosensors for the Detection of Common Oral Diseases

Limiting and preventing oral diseases remains a major challenge to the health of populations around the world, so finding ways to detect early-stage diseases (e.g., caries, periodontal disease, and oral cancer) and aiding in their prevention has always been an important clinical treatment concept. The development and application of electrochemical detection technology can provide important support for the early detection and non-invasive diagnosis of oral diseases and make up for the shortcomings of traditional diagnostic methods, which are highly sensitive, non-invasive, cost-effective, and less labor-intensive. It detects specific disease markers in body fluids through electrochemical reactions, discovers early warning signals of diseases, and realizes rapid and reliable diagnosis. This paper comprehensively summarizes the development and application of electrochemical biosensors in the detection and diagnosis of common oral diseases in terms of application platforms, sensing types, and disease detection, and discusses the challenges faced by electrochemical biosensors in the detection of oral diseases as well as the great prospects for future applications, in the hope of providing important insights for the future development of electrochemical biosensors for the early detection of oral diseases.

Synergistic Phototherapy-Molecular Targeted Therapy Combined with Tumor Exosome Nanoparticles for Oral Squamous Cell Carcinoma Treatment

Oral squamous cell carcinoma (OSCC) contributes to more than 90% of all oral malignancies, yet the performance of traditional treatments is impeded by limited therapeutic effects and substantial side effects. In this work, we report a combinational treatment strategy based on tumor exosome-based nanoparticles co-formulating a photosensitizer (Indocyanine green) and a tyrosine kinase inhibitor (Gefitinib) (IG@EXOs) for boosting antitumor efficiency against OSCC through synergistic phototherapy-molecular targeted therapy. The IG@EXOs generate distinct photothermal/photodynamic effects through enhanced photothermal conversion efficiency and ROS generation, respectively. In vivo, the IG@EXOs efficiently accumulate in the tumor and penetrate deeply to the center of the tumor due to passive and homologous targeting. The phototherapy effects of IG@EXOs not only directly induce potent cancer cell damage but also promote the release and cytoplasmic translocation of Gefitinib for achieving significant inhibition of cell proliferation and tumor angiogenesis, eventually resulting in efficient tumor ablation and lymphatic metastasis inhibition through the synergistic phototherapy-molecular targeted therapy. We envision that the encouraging performances of IG@EXOs against cancer pave a new avenue for their future application in clinical OSCC treatment.

Tumor Microenvironment-Activated Nanocomposite for Self-Amplifying Chemodynamic/Starvation Therapy Enhanced IDO-Blockade Tumor Immunotherapy

Disrupting intracellular redox homeostasis combined with immune checkpoint blockade therapy is considered as an effective way to accelerate tumor cell death. However, suppressed tumor immune microenvironment and lower cargo delivery restrict the efficiency of tumor therapy. In this study, a multifunctional tumor microenvironment (TME)-responsive nanocomposite is constructed using manganese tetroxide (Mn3 O4 )-decorated disulfide-bond-incorporated dendritic mesoporous organosilica nanoparticles (DMONs) to co-deliver indoleamine 2,3-dioxygenase (IDO) inhibitor Epacadostat (IDOi) and glucose oxidase (GOx) following modification with polyethylene glycol. Owing to the responsiveness of Mn3 O4 -decorated DMONs to the mildly acidic and glutathione (GSH) overexpressed TME, the nanocomposite can rapidly decompose and release inner contents, thus substantially improving the cargo release ability. Mn3 O4 can effectively catalyze hydrogen peroxide (H2 O2 ) decomposition to generate oxygen, enhance the ability of GOx to consume glucose to produce H2 O2 , and further promote the generation of hydroxyl radicals (•OH) by Mn2+ . Furthermore, Mn2+ -mediated GSH depletion and the production of •OH can disrupt intracellular redox homeostasis, contributing to immunogenic cell death. Simultaneously, IDOi can inhibit IDO to reverse inhibited immune response. The results show that self-amplifying chemodynamic/starvation therapy combined IDO-blockade immunotherapy synergistically inhibits tumor growth and metastasis in vivo.

Bio-Responsive Macromolecular Drug and Small-Molecular Drug Conjugates: Nanoparticulate Prodrugs for Tumor Microenvironment Heterogeneity Management and Therapeutic Response Enhancement

How to break through the poor response of current drug therapy, which often resulted from tumor microenvironment heterogeneity (TMH), remains an enormous challenge in the treatment of critical diseases. In this work, a practical solution on bio-responsive dual-drug conjugates for overcoming TMH and improving antitumor treatment, which integrates the advantages of macromolecular drugs and small-molecular drugs, is proposed. Nanoparticulate prodrugs based on small-molecular drug and macromolecular drug conjugates are designed as a robust weapon for programmable multidrug delivery at tumor-specific sites: the tumor microenvironment acid condition triggers delivery of macromolecular aptamer drugs (AX102) to manage TMH (including tumor stroma matrix, interstitial fluid pressure, vasculature network, blood perfusion, and oxygen distribution), and intracellular lysosomal acid condition activates rapid release of small-molecular drugs (doxorubicin and dactolisib) to enhance curative effects. As compared with doxorubicin chemotherapy, the tumor growth inhibition rate is enhanced by 47.94% after multiple tumor heterogeneity management. This work verifies that the nanoparticulate prodrugs facilitate TMH management and therapeutic response enhancements, as well as elucidates synergetic mechanisms for drug resistance reversal and metastasis inhibition. It is hoped that the nanoparticulate prodrugs will be an excellent demonstration of the co-delivery of small-molecular drugs and macromolecular drugs.

Activatable Graphene Quantum-Dot-Based Nanotransformers for Long-Period Tumor Imaging and Repeated Photodynamic Therapy

Photodynamic therapy (PDT) is considered as an emerging therapeutic modality against cancer with high spatiotemporal selectivity because the utilized photosensitizers (PSs) are only active and toxic upon light irradiation. To maximize its effectiveness, PDT is usually applied repetitively for ablating various tumors. However, the total overdose of PSs from repeated administrations causes severe side effects. Herein, acidity-activated graphene quantum dots-based nanotransformers (GQD NT) are developed as PS vehicles for long-period tumor imaging and repeated PDT. Under the guidance of Arg-Gly-Asp peptide, GQD NT targets to tumor tissues actively, and then loosens and enlarges in tumor acidity, thus promising long tumor retention. Afterwards, GQD NT transforms into small pieces for better penetration in tumor. Upon laser irradiation, GQD NT generates mild hyperthermia that enhances cell membrane permeability and further promotes the PSs uptake. Most intriguingly, the as-prepared GQD NT not only "turns-on" fluorescence/magnetic resonance signals, but also achieves efficient repeated PDT. Notably, the total PSs dose is reduced to 3.5 µmol kg^-1 , which is 10-30 times lower than that of other reported works. Overall, this study exploits a smart vehicle to enhance accumulation, retention, and release of PSs in tumors through programmed deformation, thus overcoming the overdose obstacle in repeated PDT.

Rational Design of Mesoporous Coordination Polymer Nanophotosensitizers for Photodynamic Tumor Ablation

Effective clinical practice of precise photodynamic therapy (PDT) is severely impeded by the inherent drawbacks and aggregation propensity of conventional photosensitizers. An all-in-one approach is highly desired to optimize structural features, photophysical properties, and pharmacokinetic behaviors of photosensitizers. Herein, we have fabricated mesoporous boron dipyrromethene-bridged coordination polymer nanophotosensitizers (BCP-NPs) for high-performance PDT via a unique solvent-assisted assembly strategy. Distinctive photophysical and structural characteristics of BCP-NPs confer enhanced photodynamic activities, together with high cellular uptake and ultrahigh stability. Moreover, BCP-NPs showed excellent tumor accumulation and prolonged tumor retention, achieving eradication of the triple-negative breast cancer (TNBC) model under low-power-density LED irradiation. This work has provided a valuable paradigm for the construction of mesoporous photoactive nanomaterials for biophotonic applications.

Ultra-Small Nano-Assemblies as Tumor-Targeted and Renal Clearable Theranostic Agent for Photodynamic Therapy

It is a challenge to design photosensitizers to balance between the tumor-targeting enrichment for precise treatment and efficient clearance within a reasonable timescale for reducing side effects. Herein, an ultra-small nano-photosensitizer 1a with excellent tumor-specific accumulation and renal clearance is reported. It is formed from the self-assembly of compound 1 bearing three triethylene glycol (TEG) arms and two pyridinium groups in water. The positively charged surface with neutral TEG coating enables 1a to efficiently target the tumor, with the signal-to-background ratio reaching as high as 11.5 after tail intravenous injection. The ultra-small size of 1a with an average diameter of 5.6 nm allows its fast clearance through kidney. Self-assembly also endows 1a with an 18.2-fold enhancement of reactive oxygygen species generation rate compared to compound 1 in organic solution. Nano-PS 1a manifests an excellent photodynamic therapy efficacy on tumor-bearing mouse models. This work provides a promising design strategy of photosensitizers with renal clearable and tumor-targeting ability.

Design of One-for-All Near-Infrared Aggregation-Induced Emission Nanoaggregates for Boosting Theranostic Efficacy

Fluorescence-guided phototherapy, including photodynamic and photothermal therapy, is considered an emerging noninvasive strategy for cancer treatments. Organic molecules are promising theranostic agents because of their facile construction, simple modification, and good biocompatibility. Organic systems that integrated multifunctionalities in a single component and achieved high efficiency in both imaging and therapies are rarely reported as the inherently competitive energy relaxation pathways are hard to modulate, and fluorescence quenching occurs upon molecular aggregation. Herein, a versatile theranostic platform with near-infrared emission, high fluorescence quantum yield, robust reactive oxygen species production, and excellent photothermal conversion efficiency was developed based on an aggregation-induced emission luminogen, namely, TPA-TBT. In vivo studies revealed that the TPA-TBT nanoaggregates exhibit outstanding photodynamic and photothermal therapy efficacy to ablate tumors inoculated in a mouse model. This work offers a design strategy to develop one-for-all cancer theranostic agents by modulating and utilizing the relaxation energy of excitons in full.

A Self-Reinforcing Nanoplatform for Highly Effective Synergistic Targeted Combinatary Calcium-Overload and Photodynamic Therapy of Cancer

While calcium-overload-mediated therapy (COMT) is a promising but largely untapped therapeutic strategy, combinatory therapy greatly boosts treatment outcomes with integrated merits of different therapies. Herein, a BPQD@CaO₂ -PEG-GPC3Ab nanoplatform is formulated by integrating calcium peroxide (CaO₂ ) and black phosphorus quantum dot (BPQD, photosensitizer) with active-targeting glypican-3 antibody (GPC3Ab), for combinatory photodynamic therapy (PDT) and COMT in response to acidic pH and near-infrared (NIR) light, wherein CaO₂ serves as the reservoir of calcium ions (Ca²⁺ ) and hydrogen peroxide (H₂ O₂ ). Navigated by GPC3Ab to tumor cells at acidic pH, the nanoparticle disassembles to CaO₂ and BPQD; CaO₂ produces COMT Ca²⁺ and H₂ O₂ , while H₂ O₂ makes oxygen (O₂ ) to promote PDT; under NIR irradiation BPQD facilitates not only the conversion of O₂ to singlet oxygen (¹ O₂ ) for PDT, but also moderate hyperthermia to accelerate NP dissociation to CaO₂ and BPQD, and conversions of CaO₂ to Ca²⁺ and H₂ O₂ , and H₂ O₂ to O₂ , to enhance both COMT and PDT. After supplementary ionomycin treatment to induce intracellular Ca²⁺ bursts, the multimodal therapeutics strikingly induce hepatocellular carcinoma apoptosis, likely through the activation of the calpains and caspases 12, 9, and 3, up-regulation of Bax and down-regulation of Bcl-2 proteins. This nanoplatform enables a mutually-amplifying and self-reinforcing synergistic therapy.

Nanomaterials targeting macrophages in sepsis: A promising approach for sepsis management

Sepsis is a life-threatening organ dysfunction resulting from dysregulated host responses to infection. Macrophages play significant roles in host against pathogens and the immunopathogenesis of sepsis, such as phagocytosis of pathogens, secretion of cytokines, and phenotype reprogramming. However, the rapid progression of sepsis impairs macrophage function, and conventional antimicrobial and supportive treatment are not sufficient to restore dysregulated macrophages roles. Nanoparticles own unique physicochemical properties, surface functions, localized surface plasmon resonance phenomenon, passive targeting in vivo, good biocompatibility and biodegradability, are accessible for biomedical applications. Once into the body, NPs are recognized by host immune system. Macrophages are phagocytes in innate immunity dedicated to the recognition of foreign substances, including nanoparticles, with which an immune response subsequently occurs. Various design strategies, such as surface functionalization, have been implemented to manipulate the recognition of nanoparticles by monocytes/macrophages, and engulfed by them to regulate their function in sepsis, compensating for the shortcomings of sepsis traditional methods. The review summarizes the mechanism of nanomaterials targeting macrophages and recent advances in nanomedicine targeting macrophages in sepsis, which provides good insight for exploring macrophage-based nano-management in sepsis.

A water-soluble thiophene-croconaine dye with a high molar extinction coefficient for NIR fluorescence imaging-guided synergistic photothermal/photodynamic therapy of cancer

Phototherapeutic agents with near-infrared (NIR) fluorescence, strong reactive oxygen species generation and photothermal conversion capabilities are highly desirable for use in cancer therapy. Herein, a water-soluble NIR croconaine dye (TCR) with a thiophene-croconaine rigid core and two symmetric alkyl chains was designed and synthesized. TCR exhibits intense NIR absorption and fluorescence that peaked at 780 and 815 nm, respectively, with a high molar extinction coefficient of 1.19 × 10⁵ M^-1 cm^-1. Moreover, TCR has a high photothermal conversion efficiency of 77% and is capable of generating hydroxyl radicals (OH˙) under 735 nm laser irradiation. Based on these outstanding properties, TCR has proven its application in NIR fluorescence imaging-guided synergistic photothermal/photodynamic therapy of cancer.

Nanotheranostic Strategies for Cancer Immunotherapy

Despite advancements in cancer immunotherapy, heterogeneity in tumor response impose barriers to successful treatments and accurate prognosis. Effective therapy and early outcome detection are critical as toxicity profiles following immunotherapies can severely affect patients' quality of life. Existing imaging techniques, including positron emission tomography, computed tomography, magnetic resonance imaging, or multiplexed imaging, are often used in clinics yet suffer from limitations in the early assessment of immune response. Conventional strategies to validate immune response mainly rely on the Response Evaluation Criteria in Solid Tumors (RECIST) and the modified iRECIST for immuno-oncology drug trials. However, accurate monitoring of immunotherapy efficacy is challenging since the response does not always follow conventional RECIST criteria due to delayed and variable kinetics in immunotherapy responses. Engineered nanomaterials for immunotherapy applications have significantly contributed to overcoming these challenges by improving drug delivery and dynamic imaging techniques. This review summarizes challenges in recent immune-modulation approaches and traditional imaging tools, followed by emerging developments in three-in-one nanoimmunotheranostic systems co-opting nanotechnology, immunotherapy, and imaging. In addition, a comprehensive overview of imaging modalities in recent cancer immunotherapy research and a brief outlook on how nanotheranostic platforms can potentially advance to clinical translations for the field of immuno-oncology is presented.

Nanomaterial-assisted CRISPR gene-engineering - A hallmark for triple-negative breast cancer therapeutics advancement

Triple-negative breast cancer (TNBC) is the most violent class of tumor and accounts for 20-24% of total breast carcinoma, in which frequently rare mutation occurs in high frequency. The poor prognosis, recurrence, and metastasis in the brain, heart, liver and lungs decline the lifespan of patients by about 21 months, emphasizing the need for advanced treatment. Recently, the adaptive immunity mechanism of archaea and bacteria, called clustered regularly interspaced short palindromic repeats (CRISPR) combined with nanotechnology, has been utilized as a potent gene manipulating tool with an extensive clinical application in cancer genomics due to its easeful usage and cost-effectiveness. However, CRISPR/Cas are arguably the efficient technology that can be made efficient via organic material-assisted approaches. Despite the efficacy of the CRISPR/Cas@nano complex, problems regarding successful delivery, biodegradability, and toxicity remain to render its medical implications. Therefore, this review is different in focus from past reviews by (i) detailing all possible genetic mechanisms of TNBC occurrence; (ii) available treatments and gene therapies for TNBC; (iii) overview of the delivery system and utilization of CRISPR-nano complex in TNBC, and (iv) recent advances and related toxicity of CRISPR-nano complex towards clinical trials for TNBC.

Supramolecular photodynamic agents for simultaneous oxidation of NADH and generation of superoxide radical

Given that Type-I photosensitizers (PSs) have hypoxia tolerance, developing general approaches to prepare Type-I PSs is of great importance, but remains a challenge. Here, we report a supramolecular strategy for the preparation of Type-I photodynamic agents, which simultaneously generate strong oxidizing cationic radicals and superoxide radicals, by introducing electron acceptors to the existing Type-II PSs. As a proof-of-concept, three electron acceptors were designed and co-assembled with a classical PS to produce quadruple hydrogen-bonded supramolecular photodynamic agents. The photo-induced electron transfer from the PS to the adjacent electron acceptor occurs efficiently, leading to the generation of a strong oxidizing PS^+• and an anionic radical of the acceptor, which further transfers an electron to oxygen to form O₂^-•. In addition, these photodynamic agents induce direct photocatalytic oxidation of NADH with a turnover frequency as high as 53.7 min^-1, which offers an oxygen-independent mechanism to damage tumors.

Boron Dipyrromethene-Based Phototheranostics for Near Infrared Fluorescent and Photoacoustic Imaging-Guided Synchronous Photodynamic and Photothermal Therapy of Cancer

The regulation of photochemical properties of phototheranostics, especially the absorption, fluorescence, singlet oxygen (¹O₂) generation, and photothermal conversion efficiency, is a hot research topic. Here, we designed and synthesized four boron dipyrromethene (BODIPY) derivatives with high absorption coefficients and intense fluorescence in the near-infrared (NIR) region. The substituted electron-donating group significantly improved ¹O₂ generation and fluorescence of BODIPYs, whereas the electron-withdrawing group boosts photothermal conversion. These hydrophobic BODIPYs were further coated with DSPE-PEG-2000 to form water dispersible nanoparticles (NPs). Among these BODIPY NPs, the B-OMe-NPs with methoxyl substituted at the meso-position showed the highest ¹O₂ generation, a photothermal conversion efficiency of 66.5%, and an NIR fluorescence peak at 809 nm. In vitro and in vivo experiments demonstrated that B-OMe-NPs might be used for NIR fluorescent and photoacoustic imaging-guided photodynamic and photothermal therapy of cancer.

Photovoltaic molecules with ultra-high light energy utilization for near-infrared laser triggered synergetic photodynamic and photothermal therapy

Photovoltaic molecules possess strong absorption in the near-infrared (NIR) region and are suitable for NIR laser-triggered phototherapy. Herein, the star molecule IEICO of organic photovoltaic materials, which has a narrow bandgap and large A-D-A conjugated structure, was prepared into water dispersive nanoparticles (NPs) through a simple self-assembly method. The obtained IEICO NPs showed a strong NIR absorption peak at 800 nm and a high ¹O₂ quantum yield of 11% and photothermal conversion efficiency of 85.4% under 808 nm laser irradiation. The ultra-high light energy utilization efficacy (∼96.4%) of the IEICO NPs enables their excellent phototherapeutic effect on tumors. The present work suggested the huge application potential of organic photovoltaic materials in the biomedical field.

Enhancing Photodynamic Therapy Efficacy Against Cancer Metastasis by Ultrasound-Mediated Oxygen Microbubble Destruction to Boost Tumor-Targeted Delivery of Oxygen and Renal-Clearable Photosensitizer Micelles

Hypoxic tumor microenvironment and nonspecific accumulation of photosensitizers are two key factors that limit the efficacy of photodynamic therapy (PDT). Herein, a strategy of oxygen microbubbles (MBs) boosting photosensitizer micelles is developed to enhance PDT efficacy and inhibit tumor metastasis by self-assembling renal-clearable ultrasmall poly(ethylene glycol)-modified protoporphyrin IX micelles (PPM) and perfluoropentane (PFP)-doped oxygen microbubbles (OPMBs), followed by ultrasound imaging-guided OPMB destruction to realize the tumor-targeted delivery of PPM and oxygen in tumor. Doping PFP into oxygen MBs increases the production of MBs and stability of oxygen MBs, allowing for persistent circulation in blood. Following co-injection, destruction of OPMBs with ultrasound leads to ∼2.2-fold increase of tumor-specific PPM accumulation. Furthermore, the burst release of oxygen by MB destruction improves tumor oxygenation from 22 to 50%, which not only raises the production of singlet oxygen but also significantly reduces the expression of hypoxia-inducible factor-1 alpha and related genes, thus preventing angiogenesis and epithelial-mesenchymal transition. It is verified that this strategy effectively eradicates orthotopic breast cancer and inhibits lung metastasis. Furthermore, the survival rate of mice bearing orthotopic pancreatic tumor is significantly extended by such interventional PDT strategy. Therefore, the combination of ultrasmall PPM and OPMBs represents a simple but effective strategy in overcoming the limitations of PDT.

Transformable Gallium-Based Liquid Metal Nanoparticles for Tumor Radiotherapy Sensitization

The past decades have witnessed an increasing interest in the exploration of room temperature gallium-based liquid metal (LM) in the field of microfluidics, soft robotics, electrobiology, and biomedicine. Herein, this study for the first time reports the utilization of nanosized gallium-indium eutectic alloys (EGaIn) as a radiosensitizer for enhancing tumor radiotherapy. The sodium alginate (Alg) functionalized EGaIn nanoparticles (denoted as EGaIn@Alg NPs) are prepared via a simple one-step synthesis method. The coating of Alg not only prevents the aggregation and oxidation of EGaIn NPs in an aqueous solution but also enables them low cytotoxicity, good biocompatibility, and in-situ formation of gels in the Ca²⁺ enriched tumor physiological microenvironment. Due to the metallic nature and high density, EGaIn can increase the generation of reactive oxygen species under the irradiation of X-ray, which can not only directly promote DNA damage and cell apoptosis, but also show an efficient tumor inhibition rate in vivo. Moreover, EGaIn@Alg NPs hold good performance as computed tomography (CT) and photoacoustic tomography (PAT) imaging contrast agents. This work provides an alternative nanotechnology strategy for tumor radiosensitization and also enlarges the biomedical application of gallium-based LM.

JAC1 targets YY1 mediated JWA/p38 MAPK signaling to inhibit proliferation and induce apoptosis in TNBC

Triple negative breast cancer (TNBC) is a type of breast cancer with poor prognosis, and has no ideal therapeutic target and ideal medicine. Downregulation of JWA is closely related to the poor overall survival in many cancers including TNBC. In this study, we reported at the first time that JWA gene activating compound 1 (JAC1) inhibited the proliferation of TNBC in vitro and in vivo experimental models. JAC1 specifically bound to YY1 and eliminated its transcriptional inhibition of JWA gene. The rescued JWA induced G1 phase arrest and apoptosis in TNBC cells through the p38 MAPK signaling pathway. JAC1 also promoted ubiquitination and degradation of YY1. In addition, JAC1 disrupted the interaction between YY1 and HSF1, and suppressed the oncogenic role of HSF1 in TNBC through p-Akt signaling pathway. In conclusion, JAC1 suppressed the proliferation of TNBC through the JWA/P38 MAPK signaling and YY1/HSF1/p-Akt signaling. JAC1 maybe a potential therapeutic agent for TNBC.

A Photosensitizer Discretely Loaded Nanoaggregate with Robust Photodynamic Effect for Local Treatment Triggers Systemic Antitumor Responses

Photodynamic therapy (PDT), is a rising star for suppression of in situ and metastatic tumors, yet it is impeded by low ROS production and off-target phototoxicity. Herein, an aggregation degree editing strategy, inspired by gene editing, was accomplished by the coordination of an aggregation degree editor, p(MEO₂MA₁₆₀-co-OEGMA₄₀)-b-pSS₃₀ [POEGS; MEO₂MA = 2-(2-methoxyethoxy)ethyl methacrylate, OEGMA = oligo(ethylene glycol) methacrylate; pSS = poly(styrene sulfonate)] and indocyanine green (ICG) to nontoxic Mg²⁺, forming an ICG discretely loaded nanoaggregate (ICG-DNA). Optimization of the ICG aggregation degree [POEGS/ICG (P/I) = 6.55] was achieved by tuning the P/I ratio, alleviating aggregation-caused-quenching (ACQ) and photobleaching concurrently. The process boosts the PDT efficacy, spurring robust immunogenic cell death (ICD) and systemic antitumor immunity against primary and metastatic immunogenic "cold" 4T1 tumors via intratumoral administration. Moreover, the temperature-sensitive phase-transition property facilitates intratumoral long-term retention of ICG-DNA, reducing undesired phototoxicity to normal tissues; meanwhile, the photothermal-induced tumor oxygenation further leads to an augmented PDT outcome. Thus, this simple strategy improves PDT efficacy, boosting the singlet oxygen quantum yield (Φ_Δ)-dependent ICD effect and systemic antitumor responses via local treatment.

Leveraging BODIPY nanomaterials for enhanced tumor photothermal therapy

In the past ten years, photothermal therapy (PTT) has attracted widespread attention in tumor treatment due to its non-invasiveness and little side effects. PTT utilizes heat produced by photothermal agents under the irradiation of near-infrared light to kill tumor cells. Boron-dipyrromethene (BODIPY), an organic phototherapy agent, has been widely used in tumor phototherapy due to its higher molar extinction coefficient, robust photostability and good phototherapy effect. However, there are some issues in the application of BODIPY for tumor PTT, such as low photothermal conversion efficiency and short absorption wavelength. In this review, we focus on the latest development of BODIPY nanomaterials for overcoming the above problems and enhancing the PTT effect.

Highly Efficient Far-Red/NIR-Absorbing Neutral Ir(III) Complex Micelles for Potent Photodynamic/Photothermal Therapy

A critical issue in photodynamic therapy (PDT) is inadequate reactive oxygen species (ROS) generation in tumors, causing inevitable survival of tumor cells that usually results in tumor recurrence and metastasis. Existing photosensitizers frequently suffer from relatively low light-to-ROS conversion efficiency with far-red/near-infrared (NIR) light excitation due to low-lying excited states that lead to rapid non-radiative decays. Here, a neutral Ir(III) complex bearing distyryl boron dipyrromethene (BODIPY-Ir) is reported to efficiently produce both ROS and hyperthermia upon far-red light activation for potentiating in vivo tumor suppression through micellization of BODIPY-Ir to form "Micelle-Ir". BODIPY-Ir absorbs strongly at 550-750 nm with a band maximum at 685 nm, and possesses a long-lived triplet excited state with sufficient non-radiative decays. Upon micellization, BODIPY-Ir forms J-type aggregates within Micelle-Ir, which boosts both singlet oxygen generation and the photothermal effect through the high molar extinction coefficient and amplification of light-to-ROS/heat conversion, causing severe cell apoptosis. Bifunctional Micelle-Ir that accumulates in tumors completely destroys orthotopic 4T1 breast tumors via synergistic PDT/photothermal therapy (PTT) damage under light irradiation, and enables remarkable suppression of metastatic nodules in the lungs, together without significant dark cytotoxicity. The present study offers an emerging approach to develop far-red/NIR photosensitizers toward potent cancer therapy.

Overcoming Tumor Hypoxia through Multiple Pathways Using an All-in-One Polymeric Therapeutic Agent to Enhance Synergistic Cancer Photo/Chemotherapy Effects

Hypoxia is a significant characteristic of tumors, which causes aggressive tumor growth and strong therapy resistance. Inspired by the improved therapeutic efficacy of synergistic treatment, herein, an all-in-one polymeric therapeutic agent was developed, which could overcome tumor hypoxia through multiple pathways. Multiple therapeutic agents were incorporated into the polymer, including the singlet oxygen (¹O₂) carrier unit to store cytotoxic reactive oxygen species, the photosensitized and photothermal unit to trigger the capture and release of ¹O₂, and the hypoxia-responsive prodrug unit to maintain a long-term tumor inhibition. In addition, the hydrophilic polyethylene glycol unit was also introduced to improve water-solubility and biocompatibility. Importantly, this study achieved the capture and controllable release of ¹O₂ just by regulating the power of an 808 nm laser for the first time, which is more convenient and flexible than previous works. As expected, the as-prepared copolymer displayed reduced oxygen dependence, accompanied with promising synergistic anti-tumor and anti-recurrence efficacies under hypoxic in vitro and in vivo environments. Consequently, this synergistic anti-hypoxia strategy may open up new avenues in the design of all-in-one therapeutic platforms for promoting the development of accurate, efficient, and long-acting treatment in clinical studies.

Stimuli-activated molecular photothermal agents for cancer therapy

Taking advantage of activatable and imaging-guided properties, stimuli-activated molecular photothermal agents (MPTAs) have drawn great attention in photothermal therapy (PTT) over the past decades. In this review, the recent progress in the study of stimuli-activated MPTAs is summarized from different stimuli, including pH, bioactive small molecules, and enzymes. The features and challenges of stimuli-activated MPTAs are also discussed. This review aims to motivate readers to design and synthesise more efficient MPTAs.