An Acceptor-π-Donor Structured Organic Chromophore for NIR Triggered Thermal Ablation of Tumor via DNA Damage-Mediated Apoptosis

4D Printing for Biomedical Applications

4D (bio-)printing endows 3D printed (bio-)materials with multiple functionalities and dynamic properties. 4D printed materials have been recently used in biomedical engineering for the design and fabrication of biomedical devices, such as stents, occluders, microneedles, smart 3D-cell engineered microenvironments, drug delivery systems, wound closures, and implantable medical devices. However, the success of 4D printing relies on the rational design of 4D printed objects, the selection of smart materials, and the availability of appropriate types of external (multi-)stimuli. Here, this work first highlights the different types of smart materials, external stimuli, and design strategies used in 4D (bio-)printing. Then, it presents a critical review of the biomedical applications of 4D printing and discusses the future directions of biomedical research in this exciting area, including in vivo tissue regeneration studies, the implementation of multiple materials with reversible shape memory behaviors, the creation of fast shape-transformation responses, the ability to operate at the microscale, untethered activation and control, and the application of (machine learning-based) modeling approaches to predict the structure-property and design-shape transformation relationships of 4D (bio)printed constructs.

Superior Photophysical and Photosensitizing Properties of Nanoaggregates of Weakly Emissive Dyes for Use in Bioimaging and Photodynamic Therapy

The development of luminescent dyes based on 1,1,4,4-tetracyanobuta-1,3-dienes (TCBDs) is an active research area, and a quantum yield (ΦF) of 7.8% has been achieved so far in cyclohexane by appending a fluorophore. Our novel method radically refines weakly emissive 2,3-disubstituted TCBD (phenyl-TCBD 1) (ΦF = 2.3% in CH3CN) into a water-soluble, biocompatible nanoformulation as highly emissive aggregates 1NPs ⊂ PF-127 with ΦF = 7.9% in H2O and without fluorophore conjugation. Characterization of 1NPs ⊂ PF-127 was carried out using various spectroscopic techniques, and its predominant size was found to be 80-100 nm according to transmission electron microscopy and dynamic light scattering techniques. Spectroscopic studies including Fourier transform infrared spectroscopy revealed that aggregated phenyl-TCBD particles were encapsulated in a nonluminescent triblock copolymer (PF-127)-based nanomicelles with the TCBD entrapment efficiency of 77%. With increasing water fraction, the phenyl-TCBD nanoaggregates exhibited a 3-fold higher quantum yield, a greater lifetime, and a red shift (155 nm). This remarkable enhancement in red emissivity enabled them to be used as a bioprobe for bioimaging applications and in photodynamic therapy to selectively target cancer cell lines with singlet oxygen generation capability (ΦΔ = 0.25). According to the MTT assay, compared to the native molecular form (1229 nM), the aggregated 1NPs ⊂ PF-127 (13.51 nM) exhibited dose-dependent cell death when exposed to light with 91-fold increased activity. The histoarchitectures of various vital organs (liver, kidneys, heart, lungs, and spleen) were intact when tested for in vivo biocompatibility. This study has significant implications for developing nonplanar push-pull chromophore-based dyes as biosensors and with potential applications beyond bioimaging.

Nanoparticle-Based Photothermal Therapy for Breast Cancer Noninvasive Treatment

Rapid advancements in materials science and nanotechnology, intertwined with oncology, have positioned photothermal therapy (PTT) as a promising noninvasive treatment strategy for cancer. The breast's superficial anatomical location and aesthetic significance render breast cancer a particularly pertinent candidate for the clinical application of PTT following melanoma. This review comprehensively explores the research conducted on the various types of nanoparticles employed in PTT for breast cancer and elaborates on their specific roles and mechanisms of action. The integration of PTT with existing clinical therapies for breast cancer is scrutinized, underscoring its potential for synergistic outcomes. Additionally, the mechanisms underlying PTT and consequential modifications to the tumor microenvironment after treatment are elaborated from a medical perspective. Future research directions are suggested, with an emphasis on the development of integrative platforms that combine multiple therapeutic approaches and the optimization of nanoparticle synthesis for enhanced treatment efficacy. The goal is to push the boundaries of PTT toward a comprehensive, clinically applicable treatment for breast cancer.

Chidamide stacked in magnetic polypyrrole nano-composites counter thermotolerance and metastasis for visualized cancer photothermal therapy

Photothermal therapy (PTT) has become one of the most promising therapies in cancer treatment as its noninvasiveness, high selectivity, and favorable compliance in clinic. However, tumor thermotolerance and distal metastasis reduce its efficacy, becoming the bottleneck of applying PTT in clinic. In this study, a chidamide-loaded magnetic polypyrrole nanocomposite (CMPP) has been fabricated as a visualized cancer photothermal agent (PTA) to counter tumor thermotolerance and metastasis. The efficacy of CMPP was characterized by in vitro and in vivo assays. As a result, this kind of magnetic polypyrrole nanocomposites were black spherical nanoparticles, possessing a favorable photothermal effect and the suitable particle size of 176.97 ± 1.45 nm with a chidamide loading rate of 12.92 ± 0.45%. Besides, comparing with PTT, CMPP exhibited significantly higher cytotoxicity and cellular apoptosis rate in two tumor cell lines (B16-F10 and HepG2). In vivo study, the mice showed obvious near-infrared (NIR) and magnetic resonance imaging (MRI) dual-modal imaging at tumor sites and sentinel lymph nodes (SLNs); on the other hand, magnetic targeting guided CMPP achieved a cure level on melanoma-bearing mice through preventing metastasis and thermotolerance. Overall, with high loading efficiency of chidamide and strong magnetic targeting to tumor sites and SLNs, CMPP could significantly raise efficiency of PTT by targeting tumor thermotolerance and metastasis, and this strategy may be exploited therapeutically to upgrade PTT with MPP as one of appropriate carriers for histone deacetylase inhibitors (HDACis).

Combination of Photothermal Therapy with Anti-Inflammation Therapy Attenuates the Inflammation Tumor Microenvironment and Weakens Immunosuppression for Enhancement Antitumor Treatment

Photothermal therapy has gained widespread attention in cancer treatment, although its efficacy is suppressed due to the inflammatory response and immunosuppression, resulting in a discounted therapeutic effect. In this contribution, a high-performance NIR absorption organic small chromophore is developed, which is encapsulated into Pluronic F-127 to fabricate NIR absorption organic nanoparticles (TTM NPs) with excellent photothermal conversion efficiency (51.49%) for photothermal therapy. TTM NPs based photothermal therapy are combined with Aspisol, a kind of nonsteroidal anti-inflammatory drug, to weaken the inflammation and immunosuppression tumor microenvironment and enhance the antitumor effect. The results prove that the combination therapy realizes effective thermal elimination of primary tumors, inhibition of distant tumors, and suppression of tumor metastasis. The data show that combination therapy can suppress the expression of inflammatory factors, enhance dendritic cell activation and maturation, reverse the immunosuppression, facilitate T cell infiltration, and restore antitumor cytotoxic T lymphocyte activity. This study provides a paradigm to extend the development of photothermal therapy.