Site-specific albumin tagging with NIR-II fluorogenic dye for high-performance and super-stable bioimaging.

Synthetic near-infrared-II (NIR-II) dyes are promising for deep tissue imaging, yet they are generally difficult to target a given biomolecule with high specificity. Furthermore, the interaction mechanism between albumin and cyanine molecules, which is usually regarded as uncertain "complexes" such as crosslinked nanoparticles, remains poorly understood. Methods: Here, we propose a new class of NIR-II fluorogenic dyes capable of site-specific albumin tagging for in situ albumin seeking/targeting or constructing high-performance cyanine@albumin probes. We further investigate the interaction mechanism between NIR-II fluorogenic dyes and albumin. Results: We identify CO-1080 as an optimal dye structure that produces a stable/bright NIR-II cyanine@albumin probe. CO-1080 exhibits maximum supramolecular binding affinity to albumin while catalyzing their covalent attachment. The probe shows exact binding sites located on Cys476 and Cys101, as identified by proteomic analysis and docking modeling. Conclusion: Our cyanine@albumin probe substantially improves the pharmacokinetics of its free dye counterpart, enabling high-performance NIR-II angiography and lymphography. Importantly, the site-specific labeling tags between NIR-II fluorogenic dyes and albumin occur under mild conditions, offering a specific and straightforward synthesis strategy for NIR-II fluorophores in the fields of targeting bioimaging and imaging-guided surgery.

Gut microbiota: A double-edged sword in immune checkpoint blockade immunotherapy against tumors.

Tumor cells can evade immune surveillance by expressing immune checkpoint molecule ligands, resulting in effective immune cell inactivation. Immune checkpoint blockades (ICBs) have dramatically improved survival of patients with multiple types of cancers. However, responses to ICB immunotherapy are heterogeneous with lower patient response rates. The advances have established that the gut microbiota can be as a promising target to overcome resistance to ICB immunotherapy. Furthermore, some bacterial species have shown to promote improved responses to ICBs. However, gut microbiota is critical in maintaining gut and systemic immune homeostasis. It not only promotes differentiation and function of immunosuppressive immune cells but also inhibits inflammatory cells via gut microbiota derived products such as short chain fatty acids (SCFAs), tryptophan (Trp) and bile acid (BA) metabolites, which play an important role in tumor immunity. Since the gut microbiota can either inhibit or enhance immune against tumor, it should be a double-edged sword in ICBs against tumor. In this review, we discuss the effects of gut microbiota on immune cells and also tumor cells, especially enhances of gut microbiota on ICB immunotherapy. These discussions can hopefully promote the development of ICB immunotherapy.

NIR-II Protein-Escaping Dyes Enable High-Contrast and Long-Term Prognosis Evaluation of Flap Transplantation.

Real-time vascular positioning, postoperative flap monitoring, and vascular reconstruction assessment are of great importance in flap transplantation. Cyanine dyes offer the advantage of high resolution in the Near-infrared-II (NIR-II) imaging window. However, the nonspecific binding of many cyanine dyes to endogenous albumin leads to high organ accumulation and skin absorption, resulting in low-quality imaging and poor reproducibility of contrast during long-term (e.g., 7 days) postoperative monitoring. Here, a novel strategy is proposed that can be widely applied to prevent protein binding for NIR-I/II Cl-containing cyanine dyes. This strategy produces protein-escaping dyes, ensuring high fluorescence enhancement in the blood with rapid clearance and no residual fluorescence, allowing for short-term repeatable injections for vascular imaging. This strategy in the perioperative monitoring of pedicle perforator flap models in mice and rats is successfully applied. Furthermore, leveraging the universality of this strategy, multiple nonoverlapping protein-escaping probes that achieve dual-excitation (808 and 1064 nm) interference-free imaging of nerve-vessel and tumor-vessel simultaneously are designed and synthesized. These protein-escaping dyes enable long-term repeatable dual-color imaging of tumor localization, resection, and tumor-vessel reconstruction at the wound site.

Immune signatures of the POLE mutation in endometrial carcinomas: a systematic study based on TCGA data and clinical cohort validation.

Background: POLE is a critical biomarker for endometrial cancer (ECs) prognosis and therapeutic decision. However, the immune infiltration and immunotherapy-related gene expression in the tumor microenvironment (TME) of POLE-mutated ECs remain unresolved. Methods: The TCGA database was used to characterize the TME of POLE mutants, which primarily included immune cells and co-expression genes. We used immunohistochemistry (IHC) to determine immune cell abundance and PD-L1 expression in 104 EC tissues, including 11 POLE mutants and 93 wild-type. Results: The bioinformatic study found significant differences in gene expression of the chemokine family, immune-cell markers, and lysozyme in POLE mutants, along with immune response activation. In POLE-mutated ECs, the abundance of CD4+T, CD8+T, M1 macrophages, and dendritic cells increased considerably. Furthermore, POLE mutations may enhance immune cell recruitment or activation and lymphocyte homing in ECs. POLE mutants also had increased expression of immune-checkpoint suppressor genes such as PD-L1, CTLA-4, TIM-3, and others. The tumor mutation burden (TMB) was higher in ECs with POLE mutation. In the validation cohort, we discovered that POLE mutations were related to the immune infiltration abundance of CD8+, CD4+, and Foxp3+ cells and PD-L1 expression by IHC. The prognosis of TCGA-ECs showed that the survival time of the CD8, CD4, PD-L1, or Foxp3 over-expression subgroup of the POLE mutants was significantly prolonged compared to the down-regulation subgroup or the POLE wild-type. Conclusion: The infiltration abundance of CD8+ T, CD4+ T, Foxp3+ T cells, and the expression of PD-L1 harbor crucial value for the prognosis or individualized therapy of POLE-mutated ECs.

Protein@Cyanine-Based NIR-II Lymphography Enables the Supersensitive Visualization of Lymphedema and Tumor Lymphatic Metastasis.

Visualization of the lymphatic system is clinically indispensable for the diagnosis and/or treatment of lymphatic diseases. Although indocyanine green (ICG) lymphography becomes an alternate imaging modality compared to traditional lymphoscintigraphy, it is still far from ideal due to the insufficient detection depth and low spatiotemporal resolution. Herein, protein@cyanine probes are rationally developed to solve the limitations of the current near-infrared-I (NIR-I) lymphography. The protein@cyanine probes are synthesized following a chlorine-containing dye-labeling strategy based on structure-selectivity (facile covalent binding between the dye and protein with a 1:1 molar ratio). As expected, the probes display exceptional NIR-II imaging ability with much-improved imaging contrast/resolution and controllable pharmacokinetics, superior to the clinical ICG. The protein@cyanine probes locate lymph nodes and delineate lymphatic vessels with super-high sensitivity and signal-to-background ratio, enabling real-time diagnosing lymphatic diseases such as lymphedema and tumor lymphatic metastasis. In particular, the NIR-II lymphography provides an opportunity to discover the disparate morbidity rate of primary lymphedema in different types of mice. Given the fact of lacking clinically transferable NIR-II probes, this work not only provides a promising strategy for enriching of the current library of NIR-II probes, but also promotes the clinical translation of NIR-II lymphography technology.

Establishment of a risk model by integrating hypoxia genes in predicting prognosis of esophageal squamous cell carcinoma.

BACKGROUND: Esophageal squamous cell carcinoma (ESCC) has a dismal prognosis, and hypoxia plays a key role in metastasis and proliferation of ESCC. Thus, we aimed to develop a hypoxia-based gene signature to assist in the treatment decisions and prognosis. METHODS: We performed consensus clustering analysis on samples from GSE53625 dataset from the Gene Expression Omnibus (GEO) database and used weighted gene co-expression network analysis to filter out candidate modules, which were then intersected with differentially expressed genes from clustered subgroups to obtain hypoxia-related genes (HRGs). After that, the aforementioned genes were used to construct risk score models and validated in The Cancer Genome Atlas (TCGA) database and Cox regression analysis were used to construct a nomogram. Immunohistochemical was used to detect protein expression levels of relevant genes. Moreover, the relationship between risk scores and tumor microenvironment was explored. RESULTS: A hypoxia risk model containing six genes (PNPLA1, CARD18, IL-18, SLC37A2, ADAMTS18, and FAM83C) was constructed by screening key HRGs. Poorer prognosis in the high-risk group than in the low-risk group. And Cox regression analysis showed that risk score was an independent prognostic factor. The nomogram based on risk scores could well predict 1-, 3-, and 5-year survival. P53, Wnt, and hypoxia signaling pathways may be some regulatory mechanisms of hypoxia associated with the tumor microenvironment. In addition, we confirmed the high expression of BGN and low expression of IL-18 in ESCC tissues. CONCLUSIONS: Our study determined the prognostic value of a 6-hypoxia gene signature and a prognostic model, providing potential prognostic predictors and therapeutic targets for ESCC.

Novel tumor-associated macrophage populations and subpopulations by single cell RNA sequencing.

Tumor-associated macrophages (TAMs) are present in almost all solid tumor tissues. 16They play critical roles in immune regulation, tumor angiogenesis, tumor stem cell activation, tumor invasion and metastasis, and resistance to therapy. However, it is unclear how TAMs perform these functions. With the application of single-cell RNA sequencing (scRNA-seq), it has become possible to identify TAM subpopulations associated with distinct functions. In this review, we discuss four novel TAM subpopulations in distinct solid tumors based on core gene signatures by scRNA-seq, including FCN1 +, SPP1 +, C1Q + and CCL18 + TAMs. Functional enrichment and gene expression in scRNA-seq data from different solid tumor tissues found that FCN1 + TAMs may induce inflammation; SPP1 + TAMs are potentially involved in metastasis, angiogenesis, and cancer cell stem cell activation, whereas C1Q + TAMs participate in immune regulation and suppression; And CCL18 + cells are terminal immunosuppressive macrophages that not only have a stronger immunosuppressive function but also enhance tumor metastasis. SPP1 + and C1Q + TAM subpopulations can be further divided into distinct populations with different functions. Meanwhile, we will also present emerging evidence highlighting the separating macrophage subpopulations associated with distinct functions. However, there exist the potential disconnects between cell types and subpopulations identified by scRNA-seq and their actual function.

Development and validation of nodal staging score in pN0 patients with esophageal squamous cell carcinoma: A population study from the SEER database and a single-institution cohort.

BACKGROUND: Patients with esophageal squamous cell carcinoma (ESCC) with lymph node metastasis may be misclassified as pN0 due to an insufficient number of lymph nodes examined (LNE). The purpose of this study was to confirm that patients with ESCC are indeed pN0 and to propose an adequate number for the correct nodal stage using the nodal staging score (NSS) developed by the beta-binomial model. METHODS: A total of 1249 patients from the Surveillance, Epidemiology, and End Results (SEER) database between 2000 and 2017, and 1404 patients diagnosed with ESCC in our database between 2005 and 2018 were included. The NSS was developed to assess the probability of pN0 status based on both databases. The effectiveness of NSS was verified using survival analysis, including Kaplan-Meier curves and Cox models. RESULTS: Many patients were misclassified as pN0 based on our algorithm due to insufficient LNE. As the number of LNE increased, false-negative findings dropped; accordingly, the NSS increased. In addition, NSS was an independent prognostic indicator for pN0 in patients with ESCC in the SEER database (hazard ratio [HR] 0.182, 95% confidence interval [CI] 0.046-0.730, p = 0.016) and our database (HR 0.215, 95% CI 0.055-0.842, p = 0.027). A certain number of nodes must be examined to achieve 90% of the NSS. CONCLUSIONS: NSS could determine the probability of true pN0 status for patients, and it was sufficient in predicting survival and obtaining adequate numbers for lymphadenectomy.

Clinicopathological Features, Staging Classification, and Clinical Outcomes of Esophageal Melanoma: Evaluation of a Pooled Case Series.

Studies that have attempted to validate the staging systems and the predictors of survival for patients with primary malignant melanoma of the esophagus (PMME) have been underpowered given their scarcity and small scale. We aimed to review a large number of PMME cases to know more about its clinicopathological features, TNM staging systems, and survival predictors of PMME. Case reports on PMME were extracted from PubMed/Medline through bibliography search and our center. A total of 287 PMME cases were identified. The majority of the patient population was male (72.08%). The most common location of PMME was the lower esophagus (50.62%) and middle esophagus (35.39%). Among the patients, 82.28% received surgical intervention. The median overall survival (OS) duration was 15 months (0.5-244). The American Joint Commission on Cancer staging classification (AJCC) for the mucosal melanoma of the upper aerodigestive tract with stage IVB and IVC integrated in stage IVA showed better distribution of OS than that for esophageal carcinoma. T stage, N stage, and surgery had significant impacts on OS duration in univariate analysis. However, only T stage and N stage were identified as independent factors for OS duration in the multivariate Cox models. PMME is an aggressive tumor with poor prognosis. The AJCC staging system for mucosal melanoma with stage IVB and IVC integrated in stage IVA may be a better option for staging PMME patients. T stage and N stage are independent factors for OS.

CSF2RB Is a Unique Biomarker and Correlated With Immune Infiltrates in Lung Adenocarcinoma.

Background: The tumor microenvironment plays an important role in the occurrence and development of tumors. However, there are gaps in understanding the molecular and cellular interactions between tumor cells and the immune tumor microenvironment (TME). The aim of this study was to identify a novel gene that played an important role in the tumor microenvironment of lung adenocarcinoma (LUAD). Methods: The gene expression profile and clinical data for LUAD were downloaded from TCGA database. First, we used the ESTIMATE algorithm to evaluate the immune and stromal scores accordingly. Also, we analyzed differentially expressed immune-related genes (IRGs) in the high and low immune/stromal score groups. Then, we used the protein-protein interaction network (PPI network) and a univariate Cox regression analysis to identify the hub gene. After that, we analyzed the relationship between CSF2RB expression and TNM stage/prognosis. Furthermore, gene set enrichment analysis (GSEA) was used to analyze the pathway regulated by CSF2RB and the Pearson correlation analysis method was used to analyze the correlation between the CSF2RB and immune cells. Finally, we used Western blot, real-time quantitative PCR (RT-qPCR), and immunohistochemistry (IHC) to validate CSF2RB expression in cancer and para-cancerous tissues. Results: We identified that CSF2RB played an important role in the tumor microenvironment of LUAD. The expression of CSF2RB in tumor tissues was lower than that in normal tissues. Furthermore, the Kaplan-Meier plotter showed that a low CSF2RB expression was associated with poor survival and multivariate COX regression analysis revealed that the CSF2RB gene was an independent risk factor for prognosis, independent of whether patients received chemotherapy or radiotherapy. More importantly, a high expression of CSF2RB was related to early T, N, and clinical stages. GSEA analysis revealed that CSF2RB associated with diverse immune-related pathways, including T-cell receptor signaling pathway, Toll-like receptor signaling pathway, and B-cell receptor signaling pathway. CSF2RB expression levels were also positively related with the levels of infiltrating CD4+ T cells, macrophages, NK cells, and monocytes in LUAD. Finally, tumor tissues from LUAD patients were used for the assessment of CSF2RB expression. It was significantly lower in tumor sites than in adjacent normal tissues, which was consistent with data analysis. Conclusion: CSF2RB effectively predicted the prognosis of patients with lung adenocarcinoma which could also be a potential target for cancer treatment and prevention. However, further studies are required to elucidate the function and regulatory mechanisms of CSF2RB and to develop some novel treatment strategies.

Influences of Ligand Backbone Substituents on Phosphinecarbonylpalladium and -nickel Catalysts for Ethylene Polymerization and Copolymerization with Polar Monomers.

A series of phosphinecarbonylpalladium and -nickel catalysts bearing various substituents on the ligand backbone were prepared, characterized, and used in ethylene polymerization and copolymerization with polar monomers. The Pd and Ni catalysts can achieve high activities as well as high polymer molecular weights in both ethylene polymerization and copolymerization with polar monomers. The electron-donating group from the carbonyl side can effectively increase the polymer molecular weights. Utilization of a cyclic backbone structure can increase the catalytic activities at the expense of the polymer molecular weights. Moreover, installation of a pyridyl moiety in the ligand backbone can enable Lewis acid responsiveness and can enhance the polymerization activities. These results suggest the importance of the ligand backbone for the properties of catalysts in ethylene polymerization and copolymerization reactions.

Myeloid-Derived Suppressor Cells in Immune Microenvironment Promote Progression of Esophagogastric Junction Adenocarcinoma.

Adenocarcinoma of the esophagogastric junction (AEG) is a fatal disease. Accumulating evidence indicates that, for a comprehensive understanding of AEG, studies should be conducted not only to investigate tumor cells, but also the tumor microenvironment (TME). In this study, we collected AEG patient data from The Cancer Genome Atlas, and used the CIBERSORT algorithm to analyze tumor-infiltrating immune cell profiles. The levels of CD8+ T cells and M0 and M2 macrophages were relatively high in AEG tissues. M2 macrophages were abundant in G3 tumors, and neutrophils were associated with poor prognosis. Myeloid-derived suppressor cells (MDSCs) represent a heterogeneous population of immunosuppressive cells which share a similar origin to neutrophils and macrophages. We further analyzed the levels of MDSCs in AEG patients and healthy donors (HD) using flow cytometry. MDSC levels were elevated at tumor sites, with polymorphonuclear MDSCs (PMN-MDSCs) being the predominant subtype. Circulating MDSCs partly represented cells at the tumor site. We observed that PMN-MDSC levels at tumor sites were positively correlated with advanced staging, low grade, lymph node metastasis, and HER2- status. Immunohistochemistry and immunofluorescence analyses indicated that activation of the STAT3 and NF-κB pathways in MDSCs may be a potential mechanism for cancer progression. Our studies provided a comprehensive perspective involving tumor-infiltrating immune cells, and detailed insights into the proportion of MDSCs in AEG and their clinical significance. Together, these findings may improve our current understanding of cancer progression involving tumor-infiltrating immune cells in the TME.

Prevention of underfeeding during enteral nutrition after gastrectomy in adult patients with gastric cancer: an evidence utilization project.

BACKGROUND: Enteral nutrition is commonly used in patients with gastric cancer after a partial or full gastrectomy since it is safe to use and nutrient delivery is in line with human physiological characteristics. However, enteral feeding often leads to deficiency, when the actual intake of the patient is lower than the target demand, which seriously affects the recovery of patients. OBJECTIVE: To implement the best practice for preventing and managing underfeeding during enteral nutrition, and to improve the nutritional status of patients with gastric cancer. METHODS: The current study was conducted following the Joanna Briggs Institute Practical Application of Clinical Evidence System program. Phase one referred to the development of the project, consisting of the generation of the best evidence, mainly based on literature review and discussions within a panel of experts. Phase two was the implementation of the project, including baseline audit, training of enteral nutrition and change of clinical practice. Phase three was a postimplementation reaudit. The intake of enteral nutrition was observed in the first 3 days, and feeding intolerance of enteral nutrition was observed within the first week of enteral nutrition. Data were collected using self-designed questionnaires. The nutritional status of patients was measured using Patient-Generated Subjective Global Assessment (PG-SGA) at admission, and 1 week after surgery. RESULTS: A total of 60 patients with gastric cancer and 10 registered nurses were enrolled in this study. The compliance rate for all audit criteria increased postimplementation. The feeding rate of enteral nutrition postimplementation was higher than the baseline audit on the third day, 54.29% (±12.01) vs. 42.89% (±10.63), and the incidence of underfeeding was lower (30%, n = 30) than the baseline audit (76.67%, n = 30). Furthermore, the feeding intolerance postimplementation (26.67%, n = 30) was lower than the baseline audit (76.67%, n = 30) within 1 week of enteral nutrition. The PG-SGA scores were not significantly different between the baseline audit and postimplementation on the day of admission, while the scores were lower postimplementation (12.90 ±â€Š1.47) compared with the baseline audit (14.00 ±â€Š1.82). CONCLUSION: In this study, we performed an audit of the clinical nursing quality, which can guide nurses to accurately identify obstacles to the implementation of enteral nutrition, and standardize the implementation and management process, thereby improving the quality of nursing and the nutritional status of patients. RELEVANCE TO CLINICAL PRACTICE: The evidence-based practice might optimize the enteral nutrition process, enhance the efficacy of enteral nutrition, and improve the nutritional status of patients. Medical staff should develop an individualized nutritional support protocol for patients based on the results of nutritional status assessments.

The Progress of Traditional Chinese Medicine in the Treatment of Aplastic Anemia.

Aplastic anemia (AA) is a common hematologic disease that is characterized by hematopoietic failure of the bone marrow and pancytopenia of the peripheral blood, which can be divided into severe and non-severe aplastic ane-mia, or acute and chronic aplastic anemia according to the severity of the disease and the progress of the clinical course. During the past years, the advantages of Traditional Chinese Medicine (TCM) on the treatment of AA have been well clarified and its theory system has been improved as well. This review is mainly on representing the pathogenesis, therapeutic principle and method, research progression, and advantages of TCM on AA.

Label-free and sequence-specific DNA detection down to a picomolar level with carbon nanotubes as support for probe DNA.

This study describes a simple and label-free electrochemical impedance spectroscopic (EIS) method for sequence-specific detection of DNA by using single-walled carbon nanotubes (SWNTs) as the support for probe DNA. SWNTs are confined onto gold electrodes with mixed self-assembly monolayers of thioethanol and cysteamine. Single-stranded DNA (ssDNA) probe is anchored onto the SWNT support through covalent binding between carboxyl groups at the nanotubes and amino groups at 5' ends of ssDNA. Hybridization of target DNA with the anchored probe DNA greatly increases the interfacial electron-transfer resistance (R(et)) at the double-stranded DNA (dsDNA)-modified electrodes for the redox couple of Fe(CN)(6)(3-/4-), which could be used for label-free and sequence-specific DNA detection. EIS results demonstrate that the utilization of SWNTs as the support for probe DNA substantially increases the surface loading of probe DNA onto electrode surface and thus remarkably lowers the detection limit for target DNA. Under the conditions employed here, R(et) is linear with the concentration of target DNA within a concentration range from 1 to 10 pM with a detection limit down to 0.8 pM (S/N=3). This study may offer a novel and label-free electrochemical approach to sensitive sequence-specific DNA detection.

Cu@Au alloy nanoparticle as oligonucleotides labels for electrochemical stripping detection of DNA hybridization.

Synthesis of the novel Cu@Au alloy nanoparticle and its application in an electrochemical DNA hybridization detection assay is described in this article. We report a low-temperature method for generating core-shell particles consisting of a core of Cu and a thin layer of Au shell that can be readily functionalized with oligonucleotides. Core-shell Cu@Au particles were successfully labeled to a 5'-alkanethiol capped oligonucleotides probe that is related to the colitoxin gene. The DNA genetic sensing assay relies on the electrostatic adsorption of target oligonucleotides onto conducting polypyrrole (PPy) surface at the glassy carbon electrode (GCE), and its hybridization to the alloy particle-oligonucleotides DNA probe. Hybridization events between probe and target were monitored by the release of the copper metal atoms anchored on the hybrids by oxidative metal dissolution and the indirectly determination of the solubilized Cu2+ ions by sensitive anodic stripping voltammetry (ASV). The detection limit is 5.0 pmol l(-1) of target oligonucleotides. The Cu@Au core-shell nanoparticles combining the surface modification properties of Au with the good electrochemical activity of Cu core shows their perspective application in the electrochemical DNA hybridization analysis assay.

Cadmium sulfide nanocluster-based electrochemical stripping detection of DNA hybridization.

A novel, sensitive electrochemical DNA hybridization detection assay, using cadmium sulfide (CdS) nanoclusters as the oligonucleotide labeling tag, is described. The assay relies on the hybridization of the target DNA with the CdS nanocluster oligonucleotide DNA probe, followed by the dissolution of the CdS nanoclusters anchored on the hybrids and the indirect determination of the dissolved cadmium ions by sensitive anodic stripping voltammetry (ASV) at a mercury-coated glassy carbon electrode (GCE). The results showed that only a complementary sequence could form a double-stranded dsDNA-CdS with the DNA probe and give an obvious electrochemical response. A three-base mismatch sequence and non-complementary sequence had negligible response. The combination of the large number of cadmium ions released from each dsDNA hybrid with the remarkable sensitivity of the electrochemical stripping analysis for cadmium at mercury-film GCE allows detection at levels as low as 0.2 pmol L(-1) of the complementary sequence of DNA.