Nanotheranostic agents capable of simultaneously enabling real-time tracking and precise treatment at tumor sites play an increasingly pivotal role in the field of medicine. In this article, we report a novel near-infrared-II window (NIR-II) emitting downconversion rare-earth nanoparticles (RENPs) to improve image-guided therapy for breast cancer. The developed α-NaErF4@NaYF4 nanoparticles (α-Er NPs) have a diameter of approximately 24.1 nm and exhibit superior biocompatibility and negligible toxicity. RENPs exhibit superior imaging quality and photothermal conversion efficiency in the NIR-II range compared to clinically approved indocyanine green (ICG). Under 808 nm laser irradiation, the α-Er NPs achieve significant tumor imaging performance and photothermal effects in vivo in a mouse model of breast cancer. Simultaneously, it combines X-ray computed tomography (CT) and ultrasound (US) tri-modal imaging to guide therapy for cancer. The integration of NIR-II imaging technology and RENPs establishes a promising foundation for future medical applications.

The high morbidity and mortality of cancer pose a severe challenge to human health. Traditional diagnostic and therapeutic strategies still exhibit obvious limitations in early diagnostic sensitivity, therapeutic precision, and real-time monitoring of treatment efficacy. The development of nanotechnology has provided novel solutions for precision cancer theranostics. Among nanomaterials, gold nanoparticles (AuNPs) have become a research hotspot in tumor nanomedicine due to their tunable size and morphology, excellent localized surface plasmon resonance (LSPR) effect, and favorable biocompatibility. However, despite encouraging preclinical outcomes, several challenges hinder their clinical translation, including an incomplete understanding of long-term toxicity, complex in vivo biological interactions, the lack of standardized evaluation protocols, and regulatory uncertainties and manufacturing reproducibility issues. This paper systematically reviews the physicochemical and biological mechanisms of AuNPs in cancer theranostics, and summarizes the latest research advances of AuNPs in cancer detection and diagnosis (including biomarker detection and multimodal imaging) as well as in therapeutic fields, covering photothermal therapy (PTT), photodynamic therapy (PDT), radiosensitization, targeted drug and nucleic acid delivery, and immunotherapy-assisted strategies. Furthermore, we discuss the development of intelligent and stimuli-responsive theranostic nanoplatforms based on AuNPs, and outline their future prospects in precision medicine and personalized cancer therapy, with particular emphasis on the requirements for clinical translation, including safety evaluation, large-scale production, and regulatory approval pathways.

Contrast-induced acute kidney injury (CIAKI) is a common complication with limited treatments. Intermedin (IMD), a peptide belonging to the calcitonin gene-related peptide family, promotes vasodilation and endothelial stability, but its role in mitigating CIAKI remains unexplored. This study investigates the protective effects of IMD in CIAKI, focusing on its mechanisms, particularly the cAMP/Rac1 signaling pathway. Human umbilical vein endothelial cells (HUVECs) were treated with iohexol to simulate kidney injury in vitro. The protective effects of IMD were assessed using CCK8 assay, flow cytometry, ELISA, and Western blotting. A CIAKI rat model was utilized to evaluate renal peritubular capillary endothelial cell injury and renal function through histopathology, immunohistochemistry, immunofluorescence, Western blotting, and transmission electron microscopy. In vitro, IMD significantly enhanced HUVEC viability and mitigated iohexol-induced toxicity by preserving intercellular adhesion junctions and activating the cAMP/Rac1 pathway, with Rac1 inhibition attenuating these protective effects. In vivo, CIAKI caused severe damage to peritubular capillary endothelial cell junctions, impairing renal function. IMD treatment markedly improved renal function, an effect negated by Rac1 inhibition. IMD protects against renal injury in CIAKI by activating the cAMP/Rac1 pathway, preserving peritubular capillary endothelial integrity and alleviating acute renal injury from contrast media. These findings suggest that IMD has therapeutic potential in CIAKI and highlight the cAMP/Rac1 pathway as a promising target for preventing contrast-induced acute kidney injury in at-risk patients, ultimately improving clinical outcomes.

Background: Atherosclerotic diseases, including coronary heart disease and cerebrovascular disease, are leading causes of morbidity and mortality worldwide. Atherosclerosis is a chronic vascular condition marked by the accumulation of lipid plaque within arterial walls. These plaques can become unstable and rupture, leading to thrombosis and subsequent cardiovascular events. Therefore, early identification of vulnerable plaque is critical for preventing such events. Objectives: This study aims to develop a novel imaging platform for atherosclerotic plaque by designing a molecular imaging probe based on fluorescent molecules that target lipid necrotic cores. The goal is to specifically detect high-risk plaque, enabling early diagnosis and intervention. Methods: Bioinformatic analysis and immunofluorescence were used to detect CD36 expression in human carotid plaque. CD36pep-ICG was synthesized using the Fmoc solid-phase peptide method. A series of experiments was conducted to characterize the probe’s properties. To assess imaging performance, probe concentration gradients were tested using FLI equipment. Ex vivo imaging was performed on atherosclerotic mice and treatment models to evaluate the probe’s targeting ability and effectiveness in monitoring disease progression. Results: The CD36 expression was significantly elevated in the core of plaque compared to distal regions. The CD36pep-ICG probe, specifically designed to target lipids, was successfully synthesized and exhibited excellent fluorescence properties. In animal models, FLI imaging demonstrated that the CD36pep-ICG probe selectively accumulated in atherosclerotic plaque, enabling precise plaque detection. Moreover, the probe was used to monitor the therapeutic efficacy of anti-atherosclerotic drugs. Conclusions: The CD36pep-ICG probe developed in this study is an effective molecular imaging tool for the specific identification of vulnerable atherosclerotic plaque, offering a novel approach for early diagnosis and treatment. Additionally, the probe shows promise in tracking the therapeutic effects of the drug, potentially advancing the precision treatment of cardiovascular diseases.

Background: Contrast-induced acute kidney injury (CIAKI) is a common complication in hospital-acquired renal conditions, yet its pathogenesis remains unclear and effective treatments are limited. Intermedin (IMD), a peptide related to the calcitonin gene, exhibits vasodilatory and endothelial barrier-stabilizing effects via the calcitonin receptor-like receptor (CLR). However, the potential of IMD in mitigating CIAKI has not been thoroughly investigated. Aims: This study aimed to delineate the protective role of IMD in CIAKI through both in vitro and in vivo models, with a particular focus on elucidating the underlying mechanisms, specifically the cAMP/Rac1 signaling pathway. Methods: Human umbilical vein endothelial cells (HUVECs) were treated with iohexol to simulate kidney injury in vitro. The protective effects of IMD were evaluated using the CCK8 assay, flow cytometry, ELISA, and western blotting. A CIAKI rat model was developed to assess renal peritubular capillary endothelial cell injury and renal function using a range of techniques, including histopathology, immunohistochemistry, immunofluorescence, western blotting, and transmission electron microscopy. Results: In vitro, IMD significantly enhanced HUVEC viability and mitigated iohexol-induced toxicity by preserving intercellular adhesion junctions and activating the cAMP/Rac1 pathway. The protective effects of IMD were attenuated by Rac1 inhibition. In vivo, CIAKI caused considerable damage to peritubular capillary endothelial cell junctions, leading to impaired renal function. IMD treatment markedly improved renal function, an effect that was abolished by Rac1 inhibition. Conclusion: IMD protects against renal injury in CIAKI by activating the cAMP/Rac1 pathway, thereby preserving the integrity of peritubular capillary endothelial cells and mitigating acute renal injury induced by contrast media. These findings underscore the therapeutic potential of IMD in CIAKI and emphasize the critical role of the cAMP/Rac1 pathway in renal protection.