Methylation of ESR1 promoter induced by SNAI2-DNMT3B complex promotes epithelial-mesenchymal transition and correlates with poor prognosis in ERα-positive breast cancers.

Estrogen receptor α (ERα) serves as an essential therapeutic predictor for breast cancer (BC) patients and is regulated by epigenetic modification. Abnormal methylation of cytosine phosphoric acid guanine islands in the estrogen receptor 1 (ESR1) gene promoter could silence or decrease ERα expression. In ERα-negative BC, we previously found snail family transcriptional repressor 2 (SNAI2), a zinc-finger transcriptional factor, recruited lysine-specific demethylase 1 to the promoter to transcriptionally suppress ERα expression by demethylating histone H3 lysine 4 dimethylation (H3K4me2). However, the role of SNAI2 in ERα-positive BC remains elusive. In this study, we observed a positive correlation between SNAI2 and ESR1 methylation, and SNAI2 promoted ESR1 methylation by recruiting DNA methyltransferase 3 beta (DNMT3B) rather than DNA methyltransferase 1 (DNMT1) in ERα-positive BC cells. Subsequent enrichment analysis illustrated that ESR1 methylation is strongly correlated with cell adhesion and junction. Knocking down DNMT3B could partially reverse SNAI2 overexpression-induced cell proliferation, migration, and invasion. Moreover, high DNMT3B expression predicted poor relapse-free survival and overall survival in ERα-positive BC patients. In conclusion, this study demonstrated the novel mechanisms of the ESR1 methylation mediated with the SNAI2/DNMT3B complex and enhanced awareness of ESR1 methylation's role in promoting epithelial-mesenchymal transition in BC.

Glutathione-Exhausting Nanoprobes for NIR-II Fluorescence Imaging-Guided Surgery and Boosting Radiation Therapy Efficacy via Ferroptosis in Breast Cancer.

Breast-conserving surgery (BCS) is the standard of care for early breast cancer patients, while the high ratio of reoperation is still a challenge due to inaccurate margin assessments. In patients with locally advanced or advanced breast cancer, radiotherapy is an important treatment for local control or improvement of quality of life. However, enhancing sensitization to radiotherapy is an unmet medical need. To solve the above clinical predicaments, a glutathione (GSH) exhausting virus-like silicon dioxide nanoprobe with Gd coating and folic acid (FA) modification is designed. After loading ICG in the mesopores, the VGd@ICG-FA probe efficiently targets tumor cells with high resolution, due to its virus-like morphology and folate acid anchoring. Especially, the fabricated nanoprobe enables the identification of tiny cancers and navigates precise surgery under NIR-II fluorescence imaging. Moreover, after the nanoprobes enter into the cytoplasm of cancer cells, tetrasulfide linkages in the silica framework are broken under the triggering of high GSH concentrations. In turn, the broken framework exhausts GSH to disrupt intracellular reactive oxygen species (ROS) homeostasis, and Gd produces more ROS under radiotherapy, further activating ferroptosis, and resulting in the enhancement of radiotherapy in breast cancer. Therefore, our nanoprobe exhibits tremendous potential as a NIR-II fluorescence imaging agent with no systematic side effects for precise cancer surgery and nanotherapeutics for boosting radiation sensitivity in future clinical translation of breast cancer.

Tumor microenvironment enhanced NIR II fluorescence imaging for tumor precise surgery navigation via tetrasulfide mesoporous silica-coated Nd-based rare-earth nanocrystals.

In vivo fluorescent imaging by using the new contrast agents emitted at short-wavelength infrared region (NIR II, 1000-1700 â€‹nm) presents an unprecedent advantages in imaging sensitivity and spatial resolution over traditional near-infrared (NIR) light. Recently, Nd-based rare-earth nanocrystals have attracted considerable attention due to the high quantum yield (∼40%) of their emission at NIR II. However, undesirable capture by reticuloendothelial system to bring strong background signal is unsatisfying for tumor discrimination. Here, GSH-sensitive tetrasulfide bond incorporated mesoporous silica shell has entrusted onto Nd-based down-conversion nanocrystals (DCNPs) surface to totally quench the fluorescence of DCNPs. After RGD conjugation on the silica surface, the NIR II contrast agents could actively target to liver tumors. Then tetrasulfide bonds can be broken during the silica framework decomposing in cytoplasm under high GSH concentration to result in NIR II fluorescence explosive recover. Benefiting from this specific response under tumor microenvironment, the NIR II signal in other organs was markedly reduced, while the signal-to-background ratio is prominently enhanced in tumors. Then, solid liver tumors were successfully resected under the guidance of our GSH responsive NIR II fluorescent imaging with no recurrence after 20-day of surgery. Meanwhile, by combining with the ignorable side effects, the Nd-based nanoprobes vastly improved the imaging resolution of tumor margin, opening a paradigm of NIR II fluorescent imaging-guided surgery.

In vivo visualization of fluorescence reflecting CDK4 activity in a breast cancer mouse model.

The CDK4/6-Rb axis is a crucial target of cancer therapy and several selective inhibitors of it have been approved for clinical application. However, current therapeutic efficacy evaluation mostly relies on anatomical imaging, which cannot directly reflect changes in drug targets, leading to a delay in the selection of optimal treatment. In this study, we constructed a novel fluorescent probe, CPP30-Lipo/CDKACT4, for real-time monitoring of CDK4 activity and the therapeutic efficacy of its inhibitor in HR+/HER2- breast cancer. CPP30-Lipo/CDKACT4 exhibited good optical stability and targetability. The signal of the probe in living cells decreased after CDK4 knockdown or palbociclib treatment. Moreover, the fluorescence intensity of the tumors after 7 days of palbociclib treatment was significantly lower than that before treatment, while no significant change in tumor diameter was observed under magnetic resonance imaging. Overall, we developed an innovative fluorescent probe that can monitor CDK4 activity and the early therapeutic response to CDK4 inhibitors in living cells and in vivo. It may provide a new strategy for evaluating antitumor therapeutic efficacy in a clinical context and for drug development.

Tumor-microenvironment triggered signal-to-noise boosting nanoprobes for NIR-IIb fluorescence imaging guided tumor surgery and NIR-II photothermal therapy.

High quantum yield quantum dots (QDs) with the emission in the sub-second near infrared window (NIR-IIb, 1500-1700 nm) can afford higher resolution, a deeper penetration depth and zero auto-fluorescence for bio-imaging. However, low tumor accumulation, the rapid renal clearance and potential toxicity impeding their biomedical applications. Here, we report a tumor microenvironment responsive hollowed virus-bionic MnO2 nanoshell with IR1061 loading in the cavity and QDs (PbS@CdS) anchoring on the surface for precise NIR-IIb fluorescence imaging guided tumor surgery and efficient NIR-II photothermal therapy. This QDs based nanoprobe could efficiently adhere on tumor cells to realize efficient tumor tissue accumulation. NIR-IIb fluorescence of tumor margin could be successfully delineating after extracellular weak acid triggered MnO2 biodegradation for IR1061 release with remarkable NIR-IIb signal-to-noise boosting. Then, it could facilitate complete dissection of various tumor models with the assistance of NIR-IIb fluorescence imaging. Moreover, the fascinating efficacy for micro-metastasis eradication via NIR-II photothermal effects can be achieved under NIR-IIb fluorescence imaging guidance. Specifically, in combination with negligible system toxicity, our nanoprobes showed great potential as a versatile NIR-IIb fluorescent imaging platform for precise tumor surgery and tumor therapy guidance for future clinical translation.

Fabrication of tumor targeting rare-earth nanocrystals for real-time NIR-IIb fluorescence imaging-guided breast cancer precise surgery.

The near-infrared fluorescence imaging has been integrated into the operating room to guide tumor resection, potentially reducing the positive margin rates in breast-conserving surgery (BCS). Relative to the widely used first near-infrared fluorescence imaging, imaging in the second near-infrared (NIR-II) region possesses higher contrast and deeper tissue penetration, particularly in the NIR-IIb window, offering many new opportunities for imaging-guided BCS. Here, we fabricated the c(RGDfC) functionalized erbium-based rare-earth nanoparticles (ErNPs@cRGD) with superior optical property in NIR-IIb region. Owing to deeper tissue penetration and efficient tumor targeting, ErNPs@cRGD-based NIR-IIb fluorescence imaging achieved enhanced signal-to-background ratios in tumor visualization, which was able to guide more complete tumor resection, identify multiple microtumors and distinguish malignant lesions from normal tissues in various mice models. Based on these, this NIR-IIb imaging strategy for surgical navigation can significantly reduce positive margin rates and improve prognosis, laying a foundation for the clinical resection of breast cancer.

Development and Preclinical Evaluation of a Near-Infrared Fluorescence Probe Based on Tailored Hepatitis B Core Particles for Imaging-Guided Surgery in Breast Cancer.

Purpose: Tumor-free surgical margin is crucial but challenging in breast-conserving surgery (BCS). Fluorescence imaging is a promising strategy for surgical navigation that can reliably assist the surgeon with visualization Of the tumor in real-time. Notably, finding an optimized fluorescent probe has been a challenging research topic. Herein, we developed a novel near-infrared (NIR) fluorescent probe based on tailored Hepatitis B Core virus-like protein (HBc VLP) and presented the preclinical imaging-guided surgery. Methods: The RGD-HBc160 VLP was synthesized by genetic engineering followed encapsulation of ICG via disassembly-reassembly. The applicability of the probe was tested for cell and tissue binding capacities through cell-based plate assays, xenograft mice model, and MMTV-PyVT mammary tumor transgenic mice. Subsequently, the efficacy of RGD-HBc160/ICG-guided surgery was evaluated in an infiltrative tumor-bearing mouse model. The protein-induced body's immune response was further assessed. Results: The prepared RGD-HBc160/ICG showed outstanding integrin αvß3 targeting ability in vitro and in vivo. After intravenous administration of probe, the fluorescence guidance facilitated more complete tumor resection and improved overall survival Of the infiltrative tumor-bearing mice. The probe also showed the excellent capability to differentiate between benign and malignant breast tissues in the mammary tumor transgenic mice. Interestingly, the ingenious tailoring of HBc VLP could not only endow its tumor-targeting ability towards integrin αvß3 but also significantly reduce the humoral and cellular immune response. Conclusion: The RGD-HBc160/ICG holds promise as an effective tool to delineate tumor margin. These results have translational potential to achieve margin-negative resection and improve the stratification of patients for a potentially curative.

Biodegradable Nanoprobe for NIR-II Fluorescence Image-Guided Surgery and Enhanced Breast Cancer Radiotherapy Efficacy.

Positive resection margin frequently exists in breast-conserving treatment (BCT) of early-stage breast cancer, and insufficient therapeutic efficacy is common during radiotherapy (RT) in advanced breast cancer patients. Moreover, a multimodal nanotherapy platform is urgently required for precision cancer medicine. Therefore, a biodegradable cyclic RGD pentapeptide/hollow virus-like gadolinium (Gd)-based indocyanine green (R&HV-Gd@ICG) nanoprobe is developed to improve fluorescence image-guided surgery and breast cancer RT efficacy. R&HV-Gd exhibits remarkably improved aqueous stability, tumor retention, and target specificity of ICG, and achieves outstanding magnetic resonance/second near-infrared (NIR-II) window multimodal imaging in vivo. The nanoprobe-based NIR-II fluorescence image guidance facilitates complete tumor resection, improves the overall mouse survival rate, and effectively discriminates between benign and malignant breast tissues in spontaneous breast cancer transgenic mice (area under the curve = 0.978; 95% confidence interval: 0.952, 1.0). Moreover, introducing the nanoprobe to tumors generated more reactive oxygen species under X-ray irradiation, improved RT sensitivity, and reduced mouse tumor progression. Notably, the nanoprobe is biodegradable in vivo and exhibits accelerated bodily clearance, which is expected to reduce the potential long-term inorganic nanoparticle toxicity. Overall, the nanoprobe provides a basis for developing precision breast cancer treatment strategies.

Surgical Navigation for Malignancies Guided by Near-Infrared-II Fluorescence Imaging.

Near-infrared (NIR) fluorescence imaging is an emerging noninvasive imaging modality, with unique advantages in guiding tumor resection surgery, thanks to its high sensitivity and instantaneity. In the past decade, studies on the conventional NIR window (NIR-I, 750-900 nm) have gradually focused on the second NIR window (NIR-II, 1000-1700 nm). With its reduced light scattering, photon absorption, and auto-fluorescence qualities, NIR-II fluorescence imaging significantly improves penetration depths and signal-to-noise ratios in bio-imaging. Recently, several studies have applied NIR-II imaging to navigating cancer surgery, including localizing cancers, assessing surgical margins, tracing lymph nodes, and mapping important anatomical structures. These studies have exemplified the significant prospects of this new approach. In this review, several NIR-II fluorescence agents and some of the complex applications for guiding cancer surgeries are summarized. Future prospects and the challenges of clinical translation are also discussed.

Current advances in the development of natural meniscus scaffolds: innovative approaches to decellularization and recellularization.

The increasing rate of injuries to the meniscus indicates the urgent need to develop effective repair strategies. Irreparably damaged menisci can be replaced and meniscus allografts represent the treatment of choice; however, they have several limitations, including availability and compatibility. Another approach is the use of artificial implants but their chondroprotective activities are still not proved clinically. In this situation, tissue engineering offers alternative natural decellularized extracellular matrix (ECM) scaffolds, which have shown biomechanical properties comparable to those of native menisci and are characterized by low immunogenicity and promising regenerative potential. In this article, we present an overview of meniscus decellularization methods and discuss their relative merits. In addition, we comparatively evaluate cell types used to repopulate decellularized scaffolds and analyze the biocompatibility of the existing experimental models. At present, acellular ECM hydrogels, as well as slices and powders, have been explored, which seems to be promising for partial meniscus regeneration. However, their inferior biomechanical properties (compressive and tensile stiffness) compared to natural menisci should be improved. Although an optimal decellularized meniscus scaffold still needs to be developed and thoroughly validated for its regenerative potential in vivo, we believe that decellularized ECM scaffolds are the future biomaterials for successful structural and functional replacement of menisci.

Serum uric acid levels in patients with myasthenia gravis are inversely correlated with disability.

Uric acid (UA), the final product of purine metabolism, has been reported to be reduced in patients with various neurological disorders and is considered to be a possible indicator for monitoring the disability and progression of multiple sclerosis. However, it remains unclear whether there is a close relationship between UA and myasthenia gravis (MG), or whether UA is primarily deficient or secondarily reduced because of its peroxynitrite scavenging activity. We investigated the correlation between serum UA levels and the clinical characteristics of MG. We assessed 338 serum UA levels obtained in 135 patients with MG, 47 patients with multiple sclerosis, and 156 healthy controls. In addition, we compared serum UA levels when MG patients were stratified according to disease activity and classifications performed by the Myasthenia Gravis Foundation of America, age of onset, duration, and thymus histology (by means of MRI or computed tomography). MG patients had significantly lower serum UA levels than the controls (P<0.001). Moreover, UA levels in patients with MG were inversely correlated with disease activity and disease progression (P=0.013). However, UA levels did not correlate significantly with disease duration, age of onset, and thymus histology. Our findings suggest that serum level of UA was reduced in patients with MG and serum UA might be considered a surrogate biomarker of MG disability and progression.

Low antioxidant status of serum bilirubin, uric acid, albumin and creatinine in patients with myasthenia gravis.

OBJECTIVE: Oxidative stress and low antioxidant status play a major role in the pathogenesis of inflammatory and autoimmune diseases. Myasthenia gravis (MG) is an autoimmune condition targeting the neuromuscular junction, and its antioxidant status is still controversial. Our study aimed to investigate the correlation between the clinical characteristics of MG and the serum antioxidant status of bilirubin (Tbil, Dbil and Ibil), uric acid, albumin and creatinine. MATERIALS AND METHODS: We measured serum antioxidant molecule levels of bilirubin (Tbil, Dbil and Ibil), uric acid, albumin and creatinine in 380 individuals, including 166 MG and 214 healthy controls. RESULTS: We found that MG patients had significantly lower serum levels of bilirubin (Tbil, Dbil and Ibil), uric acid, albumin and creatinine than healthy controls, whether male or female. Moreover, it was also shown in our study that uric acid, albumin and creatinine levels in patients with MG were correlated with disease activity and classifications performed by the Myasthenia Gravis Foundation of America. CONCLUSION: Our findings demonstrated that serum levels of bilirubin (Tbil, Dbil and Ibil), uric acid, albumin and creatinine were reduced in patients with MG. This suggested an active oxidative process in MG patients who had low antioxidant status.