pH-Responsive Plasmon-Enhanced Persistent Luminescent ZnGa2O4:Cr3+ Nanopomegranate for Tumor Imaging

Research progress of CD73-adenosine signaling regulating hepatocellular carcinoma through tumor microenvironment

Adenosine signaling pathway is a kind of signal regulation hub widely existing in human body, which is involved in a series of physiological processes such as energy supply of body cells. CD73 is a highly concerned signaling protein in purine adenosine pathway, and its role in tumor development and prognosis has been paid more and more attention in recent years, especially in hepatocellular carcinoma (HCC). In this paper, the specific mechanism by which CD73-adenosine signaling regulates tumor microenvironment (TME) of liver cancer tumors was analyzed in detail, highlighting the importance of this pathway as a therapeutic target to combat tumor immunosuppression and enhance the anti-tumor immune response to prevent and treat hepatocellular carcinoma (HCC). In addition, a variety of current targeted therapeutic strategies for adenosine metabolic pathways are summarized, including the development of new drugs in the stage of preclinical research and clinical trials, and the mechanism of action, implementation possibility, and clinical effects of these therapies are discussed. By summarizing the latest scientific research results, in this review, we attempt to paint a panorama of the mechanism of adenosine action in tumor immunotherapy, with the aim to provide a solid theoretical basis and practical guidance for subsequent research and clinical application, ultimately promoting the development of more accurate and efficient tumor immunotherapy.

One-pot synthesis of enhanced dye-sensitized persistent luminescence nanoparticles to alleviate concentration quenching

ZnGa2O4:Cr3+ (ZGC) persistent luminescence (PersL) nanoparticles (PLNPs) are extensively researched in the fields of bioimaging and therapy due to their simple preparation and uniform morphology. Typically, the luminescence intensity increases with the Cr3+ concentration of luminescent ions up to an optimal range of 0.4-0.6%, beyond which concentration quenching often occurs, leading to a decrease in both intensity and lifetime. In this study, we introduce a one-pot solvothermal synthesis method to address the issue of concentration quenching by coating ZGCn PLNPs with an optimal concentration of the organic dye OAm-RhB, yielding ZGCn@OAm-RhB PLNPs. Here, OAm-RhB serves as a strong absorber, harvesting energy and subsequent energy transfer to Cr3+. Notably, the Cr3+ doping concentration can be increased to 1.2% without causing concentration quenching. Strikingly, the energy transfer efficiency between OAm-RhB and Cr3+ is up to 71%. ZGC1.2@OAm-RhB PLNPs significantly enhance the afterglow intensity by 60 times and extend the lifetime from 85.35 to 112.05 s. After modification with DSPE-PEG and HA, ZGC1.2@OAm-RhB@PEG@HA PLNPs were obtained, demonstrating good cellular uptake and precise tumor imaging, guiding complete tumor resection confirmed by H&E staining analysis. This strategy is anticipated to mitigate the concentration quenching of other PLNPs for improving PersL performance.

Persistent luminescence nanoparticles with high intensity for colorectal cancer surgery navigation and precision resection

Surgical resection remains the main treatment for malignant tumors. Image-guided surgery aims to remove tumor tissue completely while preserving normal tissue, thereby reducing tumor recurrence rates and injury. However, challenges like tissue autofluorescence, limited probe penetration and low contrast restrict its use. Near-infrared (NIR) persistent luminescent nanoparticles (PLNPs) provide a solution by emitting persistent luminescence (PersL) even after excitation ceases, thus circumventing autofluorescence and enabling deep tumor imaging. In this study, we prepared nano-sized (140 nm hydrodynamic size) Cr3+ doped zinc gallogermanate (ZGC) using a removable template method and modified it with folate acid to obtain ZGC-FA, which exhibits NIR (695 nm) PersL with a signal-to-noise ratio of 23.9 in vivo. We utilized a colon cancer model that selectively expressed luciferase for the first time to validate the guiding efficacy of ZGC-FA in precision surgical resection. Post-intraperitoneal injection at 50 minutes, the PersL closely matched the tumor boundaries, achieving an overlap rate of approximately 98%. Complete tumor resection was achieved under PersL guidance, with only 2.3% of healthy tissue removed. This research underscores the potential of ZGC-FA in the field of surgical oncology. The precision of the ZGC-FA guided surgical approach holds promise to enhance surgical outcomes and facilitate postoperative recovery in patients.

Enhancing Persistent Luminescence through Synergy between Optimal Electron Traps and Dye Sensitization

Due to their unique afterglow ability, long-wavelength-light rechargeable persistent luminescence (PersL) nanoparticles (PLNPs) have been emerging as an important category of imaging probes. Among them, ZnGa2O4:0.6% Cr3+ (ZGC) PLNPs have gained widespread recognition due to the ease of synthesis and uniform morphology. Unfortunately, the limited absorption arising from the low molar extinction coefficient of Cr3+ results in relatively low afterglow intensity and rapid decay after long-wavelength LED light irradiation. Herein, we discovered a strategy that boosting dye-sensitization performance was able to effectively amplify the PersL signal under white LED light. Specifically, Dil served as a highly efficient sensitizer for Cr3+, promoting the absorption of the excitation light. By adjusting the Pr dopant concentrations, ZGCP0.5 PLNPs with optimal trap densities were obtained, which showed the highest PersL intensity and dye-sensitized performance. Strikingly, ZGCP0.5-Dil PLNPs exhibited a 24.3-fold enhancement in intensity and a 2-fold prolongation of decay time over bare ZGC PLNPs through the synergy effect of optimal electron traps and dye sensitization. Photostable ZGCP0.5-Dil PLNPs enabled imaging of the HepG2 tumor and effectively guided tumor surgical resection verified by the H&E staining analysis. This strategy could be a significant reference in other dye-sensitization PLNPs to enhance longer-wavelength rechargeable PersL.