Rhythm Mild-Temperature Photothermal Therapy Enhancing Immunogenic Cell Death Response in Oral Squamous Cell Carcinoma

Self-enhanced regulation of stable organic radicals with polypeptide nanoparticles for mild second near-infrared phototheranostics

Stable organic radicals have emerged as a promising option to enhance fluorescence quantum yield (QY), gaining traction in medical treatment due to their unique electronic transitions from the ground state (D0) to the doublet excited state (D1). We synthesized a stable dicyanomethyl radical with a NIR-II fluorescence QY of 0.86 %, surpassing many NIR-II organic dyes. Subsequently, amphiphilic polymer-encapsulated nanoparticles (NPs) containing the radical were created, achieving a NIR-II fluorescence QY of 0.32 %, facilitating high-contrast bio-imaging. These CNPPs exhibit self-enhanced photothermal properties, elevating photothermal conversion efficiency (PCE) from 43.5 % to 57.5 % under 915 nm laser irradiation. This advancement enables more efficient photothermal therapy (PTT) with lower dye concentrations and reduced laser power, enhancing both feasibility and safety. Through regular fractionated mild photothermal therapy, we observed the release of damage-associated molecular patterns (DAMPs) and an increase in cytokine expression, culminating in combined mild phototherapy (m-PTT)-mediated immunogenic cell death (ICD). Consequently, we developed an immunostimulatory tumor vaccine, showcasing a novel approach for refining photothermal agents (PTA) and optimizing the PTT process.

Immunogenic cell death-based cancer vaccines: promising prospect in cancer therapy

Tumor immunotherapy is a promising approach for addressing the limitations of conventional tumor treatments, such as chemotherapy and radiotherapy, which often have side effects and fail to prevent recurrence and metastasis. However, the effectiveness and sustainability of immune activation in tumor immunotherapy remain challenging. Tumor immunogenic cell death, characterized by the release of immunogenic substances, damage associated molecular patterns (DAMPs), and tumor associated antigens, from dying tumor cells (DTCs), offers a potential solution. By enhancing the immunogenicity of DTCs through the inclusion of more immunogenic antigens and stimulating factors, immunogenic cell death (ICD) based cancer vaccines can be developed as a powerful tool for immunotherapy. Integrating ICD nanoinducers into conventional treatments like chemotherapy, photodynamic therapy, photothermal therapy, sonodynamic therapy, and radiotherapy presents a novel strategy to enhance treatment efficacy and potentially improve patient outcomes. Preclinical research has identified numerous potential ICD inducers. However, effectively translating these findings into clinically relevant applications remains a critical challenge. This review aims to contribute to this endeavor by providing valuable insights into the in vitro preparation of ICD-based cancer vaccines. We explored established tools for ICD induction, followed by an exploration of personalized ICD induction strategies and vaccine designs. By sharing this knowledge, we hope to stimulate further development and advancement in the field of ICD-based cancer vaccines.

Macrophage-Capturing Self-Assembly Photosensitizer Nanoparticles Induces Immune Microenvironment Re-Programming and Golgi-Responsive Immunogenic Cell Death in Head and Neck Carcinoma

Head and neck carcinoma treatment is shifted toward the combination of therapy causing immune checkpoint blockade (ICB) and immunogenic cell death. In this study, a CSFRi-chimeric TAMCSFR+-targeting extracellular vesicle (EV@CSFRi) platform is developed and designed an intracellular protoporphyrin conjugated with RVRR peptide sequence for furin-cleavage to perform Golgi-targeting and generating ROS (GT-RG). The graphical abstract illustrates the self-assembly of GT-RG nanoparticles into nanofiber through the hydrophily of RVRR and hydrophobicity of RG, and the red line indicates the site of furin cleavage. As is shown in the Graphical abstract, the Golgi-targeting Protoporphyrin-RVRR platform is composed with CSFRi-chimeric extracellular vesicles and forms the tumor-responsive TAM-reprogramming bilayers (GT-RGEV@CSFRi). The GT-RGEV@CSFRi acted as a multifunctional theranostic platform, which can induce immunogenic cell death and further help modulate TAM, thus suppressing the HNC xenograft model by combination therapy with anti-PD-1.

Magnetic Hydroxyapatite-Coated Iron-Chromium Microspheres for Dental Surface Polishing and Plaque Removal

This research aimed to engineer magnetic hydroxyapatite-coated iron-chromium (HAp-FeCr) microspheres to enhance dental surface polishing and plaque elimination. Utilizing a tailored sol-gel approach, the HAp-FeCr microspheres were synthesized and exhaustively characterized via scanning electron microscopy, energy-dispersive X-ray spectroscopy, ζ-potential, X-ray diffractometry, and X-ray photoelectron spectroscopy methodologies. Key findings showcased that these microspheres retained their magnetic properties post-HAp coating, as evidenced by the magnetization curves. An innovative magnetic polishing system was developed, incorporating these microspheres and a 2000 rpm magnet. Comparative evaluations between traditional air-powder polishing and the proposed magnetic technique demonstrated the latter's superiority. Notably, the magnetic polishing led to a substantial reduction in dental plaque on the tooth surface, decreasing bacterial adhesion and early biofilm formation by Streptococcus gordonii and Lactobacillus acidophilus, where the most pronounced effects were observed in samples with elevated HAp content. A significant 60% reduction in dental plaque was achieved with the magnetic method relative to air-powder polishing. Furthermore, the HAp-FeCr microspheres' biocompatibility was verified through cytotoxicity tests and animal studies. In essence, the magnetic HAp-FeCr microspheres present a novel and efficient strategy for dental treatments, holding immense potential for improving oral health.

Doxorubicin-Based Ionic Nanomedicines for Combined Chemo-Phototherapy of Cancer

Synergistic combination therapy approach offers lots of options for delivery of materials with anticancer properties, which is a very promising strategy to treat a variety of malignant lesions with enhanced therapeutic efficacy. The current study involves a detailed investigation of combination ionic nanomedicines where a chemotherapeutic drug is coupled with a photothermal agent to attain dual mechanisms (chemotherapy (chemo) and photothermal therapy (PTT)) to improve the drug's efficacy. An FDA-approved Doxorubicin hydrochloride (DOX·HCl) is electrostatically attached with a near-infrared cyanine dye (ICG, IR783, and IR820), which serves as a PTT drug using ionic liquid chemistry to develop three ionic material (IM)-based chemo-PTT drugs. Carrier-free ionic nanomedicines (INMs) are derived from ionic materials (IMs). The photophysical properties of the developed combination IMs and their INMs were studied in depth. The phototherapeutic efficiency of the combination drugs was evaluated by measuring the photothermal conversion efficiency and singlet-oxygen quantum yield. The improved photophysical properties of the combination nanomedicines in comparison to their parent compounds significantly enhanced INMs' photothermal efficiency. Cellular uptake, dark and light toxicity studies, and cell death mechanisms of the chemo-PTT nanoparticles were also studied in vitro. The combination INMs exhibited enhanced cytotoxicity compared to their respective parent compounds. Moreover, the apoptosis cell death mechanism was almost doubled for combination nanomedicine than the free DOX, which is attributed to enhanced cellular uptake. Examination of the combination index and improved in vitro cytotoxicity results revealed a great synergy between chemo and PTT drugs in the developed combination nanomedicines.

Amplifying "eat me signal" by immunogenic cell death for potentiating cancer immunotherapy

Immunogenic cell death (ICD) is a unique mode of cell death, which can release immunogenic damage-associated molecular patterns (DAMPs) and tumor-associated antigens to trigger long-term protective antitumor immune responses. Thus, amplifying "eat me signal" during tumor ICD cascade is critical for cancer immunotherapy. Some therapies (radiotherapy, photodynamic therapy (PDT), photothermal therapy (PTT), etc.) and inducers (chemotherapeutic agents, etc.) have enabled to initiate and/or facilitate ICD and activate antitumor immune responses. Recently, nanostructure-based drug delivery systems have been synthesized for inducing ICD through combining treatment of chemotherapeutic agents, photosensitizers for PDT, photothermal transformation agents for PTT, radiosensitizers for radiotherapy, etc., which can release loaded agents at an appropriate dosage in the designated place at the appropriate time, contributing to higher efficiency and lower toxicity. Also, immunotherapeutic agents in combination with nanostructure-based drug delivery systems can produce synergetic antitumor effects, thus potentiating immunotherapy. Overall, our review outlines the emerging ICD inducers, and nanostructure drug delivery systems loading diverse agents to evoke ICD through chemoradiotherapy, PDT, and PTT or combining immunotherapeutic agents. Moreover, we discuss the prospects and challenges of harnessing ICD induction-based immunotherapy, and highlight the significance of multidisciplinary and interprofessional collaboration to promote the optimal translation of this treatment strategy.

Phytic acid-Cu2+ framework/Cu2-xS nanocomposites with heat-shock protein down-modulation ability for enhanced multimodal combination therapy

Mild-temperature photothermal therapy (mPTT) has shown some advantages over traditional photothermal therapy, such as reducing the damage to surrounding healthy tissues and minimizing side effects. Nevertheless, cancer cells can easily repair damage caused by mild hyperthermia due to heat shock proteins (HSPs). Thus, it is imperative to maximize the mPTT efficiency by down-regulating HSPs overexpression and combining other cancer treatments. Herein, we report the synthesis of phytic acid (PA)-Cu2+ framework/copper sulfide (Cu2-xS) nanocomposites (abbreviated as PA-Cu/Cu2-xS NPs) as the novel therapeutic platform that can down-regulate HSPs overexpression for enhanced multimodal mPTT/chemodynamic therapy (CDT)/chemotherapy. PA-Cu/Cu2-xS NPs were prepared through self-assembly and in-situ vulcanization strategy, resulting in irregular-shaped particles with an approximate size of 100 nm. PA-Cu/Cu2-xS NPs display a plasmon effect from Cu2-xS, which enhances near-infrared (NIR) absorption and possesses excellent photothermal conversion efficiency (41.7%). Moreover, PA-Cu/Cu2-xS NPs exhibit Fenton-like reaction activity resulting from the Cu ions for CDT, and the reaction activity can be further improved 1.3 times due to mild hyperthermia during mPTT. Furthermore, the generated hydroxyl radical (•OH) can effectively decrease HSPs level to enhance mPTT. PA-Cu/Cu2-xS NPs can also serve as a drug delivery system, and they are capable of loading doxorubicin (DOX) with a loading ability (20.7%). Combining mPTT/CDT/chemotherapy exhibits significant inhibition of tumor growth. This approach can serve as a basis for designing more exquisite platforms that combine mPTT with other therapies to achieve more effective cancer treatment.

Iron, Ferroptosis, and Head and Neck Cancer

Ferroptosis is an iron-dependent regulatory form of cell death characterized by the accumulation of intracellular reactive oxygen species and lipid peroxidation. It plays a critical role not only in promoting drug resistance in tumors, but also in shaping therapeutic approaches for various malignancies. This review aims to elucidate the relationship between ferroptosis and head and neck cancer treatment by discussing its conceptual framework, mechanism of action, functional aspects, and implications for tumor therapy. In addition, this review consolidates strategies aimed at improving the efficacy of head and neck cancer treatment through modulation of ferroptosis, herein serving as a valuable reference for advancing the treatment landscape for this patient population.

Lipid-Polymer Hybrid Nanoparticles with Both PD-L1 Knockdown and Mild Photothermal Effect for Tumor Photothermal Immunotherapy

In developing countries, the incidence of colorectal cancer (CRC) is on the rise. The combination of programmed cell death ligand-1 (PD-L1) siRNA (siPD-L1) and mild photothermal therapy (PTT) is a promising strategy for CRC treatment. In this study, dopamine-modified polyethylenimine (PEI) was prepared to fabricate an IR780 and siPD-L1 codelivery lipid-polymer hybrid nanoparticle (lip@PSD-siP) for the photothermal immunotherapy of CRC. The modification of dopamine can significantly reduce the cytotoxicity of PEI. lip@PSD-siP can be effectively taken up by CT26 cells and successfully escaped from lysosomes after entering the cells for 4 h. After CT26 cells were transfected with lip@PSD-siP, the PD-L1 positive cell rate decreased by 82.4%, and its PD-L1 knockdown effect was significantly stronger than the positive control Lipo3000-siP. In vivo studies showed that lip@PSD-siP-mediated mild PTT and efficient PD-L1 knockdown exhibited primary and distal tumor inhibition, metastasis delay, and rechallenged tumor inhibition. The treatment with lip@PSD-siP significantly promoted the maturation of dendritic cells in lymph nodes. The amount of T cell infiltration in the tumor tissues increased significantly, and the frequency of CD8+ T cells and CD4+ T cells was significantly higher than that of other groups. The percentage of immunosuppressive regulatory cells (Tregs) in the tumor tissue on the treatment side decreased by 88% compared to the PBS group, and the proportion of CD8+CD69+ T cells in the distal tumor tissue was 2.8 times that of the PBS group. The memory T cells of mice in the long-term antitumor model were analyzed. The results showed that after treatment with lip@PSD-siP, the frequency of effector memory T cells (Tem cells) significantly increased, suggesting the formation of immune memory.

Nanoparticles as drug delivery systems in the treatment of oral squamous cell carcinoma: current status and recent progression

Oral squamous cell carcinoma (OSCC) is a common human malignancy with an estimated incidence of around 377,713 new cases worldwide in 2020. Despite the advance in clinical management, some of OSCC patients still miss the opportunity of completable resection of tumor, and have to accept medical therapies, e.g., chemotherapy, radiotherapy, or immunotherapy when the disease develops into the advanced stage. However, these therapies have been reported to be far from ideal due to the low efficiency of conventional delivery approaches. To obtain a better therapeutic effect, considerable attempts have been made toward to develop an effective drug delivery system (DDS). Nanoparticles (NPs) including inorganic NPs, polymer NPs, lipid NP, extracellular vesicles and cell membrane-based NPs have been evaluated as the better DDS candidates that can specifically accumulate in the tumor microenvironment along with a large amount of blood vessels. Emerging evidence suggested that NPs formulated with anticancer drugs including chemotherapeutic drugs, radiotherapy and immunotarget antibodies could remarkably improve the release and increase concentration of these drugs at the tumor site and show a better therapeutic efficacy, suggesting that NPs might serve as promising DDSs in the treatment of OSCC. Therefore, we have conducted this review to summarize recent progression and current status of diverse NPs as DDSs in this research field.