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In this work, a series of cationic luminogens (designated as PSMP isomers) were developed based on the cyano positional isomerism strategy. The isomerism of the cyano substituent on the molecular skeleton can finely regulate the optical behaviour, the type of photoinduced reactive oxygen species (ROS), and mitochondria-targeted capability of isomers. Interestingly, PSMP-4, with the cyano group installed at an appropriate location, exhibits a special aggregation-induced emission effect and potent O2˙− generation efficacy through the type I photochemistry pathway. Notably, PSMP-4 can accumulate in mitochondria with high specificity. Taking advantage of its excellent photostability, PSMP-4 realizes in situ mitochondria imaging in a washing-free manner and sensitive response to the change of mitochondrial membrane potential. The integration of comprehensive photophysical properties and mitochondrial specificity enable PSMP-4 to successfully trigger the death of cancer cells through an efficient type I photodynamic therapy process both in vitro and in multicellular tumor spheroid models. [ABSTRACT FROM AUTHOR]

Simple Summary: Here, we show that the plant-derived product, sanguinarine, inhibited aerobic glycolysis and oxidative phosphorylation; which resulted in energy alternations and necroptosis of tumor cells. Moreover, we identify the PKM2/β-catenin axis as the main target in sanguinarine treatment against HCC development. Backgrounds: Abnormal metabolism is the hallmark of hepatocellular carcinoma. Targeting energy metabolism has become the major focus of cancer therapy. The natural product, sanguinarine, displays remarkable anti-tumor properties by disturbing energy homeostasis; however, the underlying mechanism has not yet been elucidated. Methods: The anticancer activity of sanguinarine was determined using CCK-8 and colony formation assay. Morphological changes of induced cell death were observed under electron microscopy. Necroptosis and apoptosis related markers were detected using western blotting. PKM2 was identified as the target by transcriptome sequencing. Molecular docking assay was used to evaluate the binding affinity of sanguinarine to the PKM2 molecule. Furthermore, Alb-CreERT2; PKM2loxp/loxp; Rosa26RFP mice was used to construct the model of HCC—through the intervention of sanguinarine in vitro and in vivo—to accurately explore the regulation effect of sanguinarine on cancer energy metabolism. Results: Sanguinarine inhibited tumor proliferation, metastasis and induced two modes of cell death. Molecular docking of sanguinarine with PKM2 showed appreciable binding affinity. PKM2 kinase activity and aerobic glycolysis rate declined, and mitochondrial oxidative phosphorylation was inhibited by sanguinarine application; these changes result in energy deficits and lead to necroptosis. Additionally, sanguinarine treatment prevents the translocation of PKM2 into the nucleus and suppresses the interaction of PKM2 with β-catenin; the transcriptional activity of PKM2/β-catenin signaling and its downstream genes were decreased. Conclusions: Sanguinarine showed remarkable anti-HCC activity via regulating energy metabolism by PKM2/β-catenin signaling. On the basis of these investigations, we propose that sanguinarine might be considered as a promising compound for discovery of anti-HCC drugs. [ABSTRACT FROM AUTHOR]

Lipid droplets (LDs), which are the hubs of lipid metabolism, play a critical role in maintaining cellular energy homeostasis. The construction of advanced photosensitizers (PSs) capable of manipulating LD‐mediated cell fate regulation is highly desirable though rarely reported. In this study, a near‐infrared emissive PS (DPCMP) with LDs specificity was synthesized and successfully applied to induce ferroptosis and apoptosis. DPCMP exhibited typical aggregation‐induced emission characteristics owing to its twisted molecular conformation. Excellent biocompatibility and suitable lipophilicity allowed DPCMP to specifically stain the LDs in living cells. Under white light illumination, the DPCMP displayed potent reactive oxygen species (ROS) generation capacity through both type I and II photochemistry. The massive accumulation of lethal ROS generated by DPCMP‐mediated photosensitization initiated lipid peroxidation, impaired cellular redox homeostasis, and led to endoplasmic reticulum oxidative stress, ultimately inhibiting cellular proliferation via concurrent ferroptosis and apoptosis in both living cancer cells and multicellular tumor spheroids. [ABSTRACT FROM AUTHOR]

Negative Poisson's ratio materials have the advantages of good shear resistance, dent resistance, and fracture resistance. Thus, they have great application potential in the manufacturing field with high requirements for material mechanical flexibility. However, negative Poisson's ratio materials are relatively rare. In this paper, the first principles calculation is used to study the single-layer P2/m-P phosphorene. It is found that when −5% to 5% strain is applied along the zigzag (Y) direction, there is a negative Poisson's ratio effect along the Z direction, and Poisson's ratio is −0.288, which is about ten times that of the single-layer black phosphorus (the negative Poisson's ratio of the single-layer black phosphorus is −0.027). Compared with black phosphorene, it has more potential applications in wearable and impact resistant equipment. [ABSTRACT FROM AUTHOR]