Photothermal-Triggered Sulfur Oxide Gas Therapy Augments Type I Photodynamic Therapy for Potentiating Cancer Stem Cell Ablation and Inhibiting Radioresistant Tumor Recurrence

Applications of Hydrogels in Osteoarthritis Treatment

This review critically evaluates advancements in multifunctional hydrogels, particularly focusing on their applications in osteoarthritis (OA) therapy. As research evolves from traditional natural materials, there is a significant shift towards synthetic and composite hydrogels, known for their superior mechanical properties and enhanced biodegradability. This review spotlights novel applications such as injectable hydrogels, microneedle technology, and responsive hydrogels, which have revolutionized OA treatment through targeted and efficient therapeutic delivery. Moreover, it discusses innovative hydrogel materials, including protein-based and superlubricating hydrogels, for their potential to reduce joint friction and inflammation. The integration of bioactive compounds within hydrogels to augment therapeutic efficacy is also examined. Furthermore, the review anticipates continued technological advancements and a deeper understanding of hydrogel-based OA therapies. It emphasizes the potential of hydrogels to provide tailored, minimally invasive treatments, thus highlighting their critical role in advancing the dynamic field of biomaterial science for OA management.

Platelet Membrane Biomimetic Manganese Carbonate Nanoparticles Promote Breast Cancer Stem Cell Clearance for Sensitized Radiotherapy

Introduction

The presence of cancer stem cells (CSCs) significantly limits the therapeutic efficacy of radiotherapy (RT). Efficient elimination of potential CSCs is crucial for enhancing the effectiveness of RT.

Methods

In this study, we developed a biomimetic hybrid nano-system (PMC) composed of MnCO3 as the inner core and platelet membrane (PM) as the outer shell. By exploiting the specific recognition properties of membrane surface proteins, PMC enables precise targeting of CSCs. Sonodynamic therapy (SDT) was employed using manganese carbonate nanoparticles (MnCO3 NPs), which generate abundant reactive oxygen species (ROS) upon ultrasound (US) irradiation, thereby impairing CSC self-renewal capacity and eradicating CSCs. Subsequent RT effectively eliminates common tumor cells.

Results

Both in vitro cell experiments and in vivo animal studies demonstrate that SDT mediated by PMC synergistically enhances RT to selectively combat CSCs while inhibiting tumor growth without noticeable side effects.

Discussion

Our findings offer novel insights for enhancing the efficacy and safety profiles of RT.

Recent advances in sulfur dioxide releasing nanoplatforms for cancer therapy

Sulfur dioxide (SO2), long considered to be a harmful atmospheric pollutant, has recently been posited as the fourth gasotransmitter, as it is produced endogenously in mammals and has important pathophysiological effects. The field of tumor therapy has witnessed a paradigm shift with the emergence of SO2-based gas therapy. This has been possible because SO2 is a potent glutathione consumer that can promote the production of reactive oxygen species, eventually leading to oxidative-stress-induced cancer cell death. Nevertheless, this therapeutic gas cannot be directly administrated in gaseous form. Thus, various nano formulations incorporating SO2 donors or prodrugs capable of storing and releasing SO2 have been developed in an attempt to achieve active/passive intratumoral accumulation and SO2 release in the tumor microenvironment. In this review article, the advances over the past decade in nanoplatforms incorporating sulfur SO2 prodrugs to provide controlled release of SO2 for cancer therapy are summarized. We first describe the synthesis of polypeptide SO2 prodrugs to overcome multiple drug resistance that was pioneered by our group, followed by other macromolecular SO2 prodrug structures that self-assemble into nanoparticles for tumor therapy. Second, we describe nanoplatforms composed of various small-molecule SO2 donors with endogenous or exogenous stimuli responsiveness, including thiol activated, acid-sensitive, and ultraviolet or near-infrared light-responsive SO2 donors, which have been used for tumor inhibition. Combinations of SO2 gas therapy with photodynamic therapy, chemotherapy, photothermal therapy, sonodynamic therapy, and nanocatalytic tumor therapy are also presented. Finally, we discuss the current limitations and challenges and the future outlook for SO2-based gas therapy. STATEMENT OF SIGNIFICANCE: Gas therapy is attracting increasing attention in the scientific community because it is a highly promising strategy against cancer owing to its inherent biosafety and avoidance of drug resistance. Sulfur dioxide (SO2) is recently found to be produced endogenously in mammals with important pathophysiological effects. This review summarizes recent advances in SO2 releasing nanosystems for cancer therapy, including polymeric prodrugs, endogenous or exogenous stimulus-activated SO2 donors delivered by nanoplatform and combination therapy strategies.

Recent advances in aggregation-induced emission-active type I photosensitizers with near-infrared fluorescence: From materials design to therapeutic platform fabrication

Near-infrared (NIR) fluorescence imaging-guided photodynamic therapy (PDT) technology plays an important role in treating various diseases and still attracts increasing research interests for developing novel photosensitizers (PSs) with outstanding performances. Conventional PSs such as porphyrin and rhodamine derivatives have easy self-aggregation properties in the physiological environment due to their inherent hydrophobic nature caused by their rigid molecular structure that induces strong intermolecular stacking π-π interaction, leading to serious fluorescence quenching and cytotoxic reactive oxygen species (ROS) reduction. Meanwhile, hypoxia is an inherent barrier in the microenvironment of solid tumors, seriously restricting the therapeutic outcome of conventional PDT. Aforementioned disadvantages should be overcome urgently to enhance the therapeutic effect of PSs. Novel NIR fluorescence-guided type I PSs with aggregation-induced emission (AIE), which features the advantages of improving fluorescent intensity and ROS generation efficiency at aggregation as well as outstanding oxygen tolerance, bring hope for resolving aforementioned problems simultaneously. At present, plenty of research works fully demonstrates the advancement of AIE-active PDT based on type I PSs. In this review, cutting-edge advances focusing on AIE-active NIR type I PSs that include the aspects of the photochemical mechanism of type I ROS generation, various molecular structures of reported type I PSs with NIR fluorescence and their design strategies, and typical anticancer applications are summarized. Finally, a brief conclusion is obtained, and the underlying challenges and prospects of AIE-active type I PSs are proposed.