Manganese self-boosting hollow nanoenzymes with glutathione depletion for synergistic cancer chemo-chemodynamic therapy.

Chemodynamic therapy (CDT) has outstanding potential as a combination therapy to treat cancer. However, the effectiveness of CDT in the treatment of solid tumors is limited by the overexpression of glutathione (GSH) in the tumor microenvironment (TME). GSH overexpression diminishes oxidative stress and attenuates chemotherapeutic drug-induced apoptosis in cancer cells. To counter these effects, a synergistic CDT/chemotherapy cancer treatment, involving the use of a multifunctional bioreactor of hollow manganese dioxide (HMnO2) loaded with cisplatin (CDDP), was developed. Metal nanoenzymes that can auto-degrade to produce Mn2+ exhibit Fenton-like, GSH-peroxidase-like activity, which effectively depletes GSH in the TME to attenuate the tumor antioxidant capacity. In an acidic environment, Mn2+ catalyzed the decomposition of intra-tumor H2O2 into highly toxic ·OH as a CDT. HMnO2 with large pores, pore volume, and surface area exhibited a high CDDP loading capacity (>0.6 g-1). Treatment with CDDP-loaded HMnO2 increased the intratumor Pt-DNA content, leading to the up-regulation of γ-H2Aχ and an increase in tumor tissue damage. The decreased GSH triggered by HMnO2 auto-degradation protected Mn2+-generated ·OH from scavenging to amplify oxidative stress and enhance the efficacy of CDT. The nanoenzymes with encapsulated chemotherapeutic agents deplete GSH and remodel the TME. Thus, tumor CDT/chemotherapy combination therapy is an effective therapeutic strategy.

An antagonist-based two-photon fluorogenic probe for imaging metabotropic glutamate receptor 5 in neuronal cells.

The expression of metabotropic glutamate receptor 5 (mGluR5) is subject to developmental regulation and undergoes significant changes in neuropsychiatric disorders and diseases. Visualizing mGluR5 by fluorescence imaging is a highly desired innovative technology for biomedical applications. Nevertheless, there are substantial problems with the chemical probes that are presently accessible. In this study, we have successfully developed a two-photon fluorogenic probe, mGlu-5-TP, based on the structure of mGluR5 antagonist 6-methyl-2-(phenylethynyl)pyridine (MPEP). Due to this antagonist-based probe selectively recognizes mGluR5, high expression of mGluR5 on living SH-SY5Y human neuroblastoma cells has been detected during intracellular inflammation triggered by lipopolysaccharides (LPS). Of particular significance, the probe can be employed along with two-photon fluorescence microscopy to enable real-time visualization of the mGluR5 in Aß fiber-treated neuronal cells, thereby establishing a connection to the progression of Alzheimer's disease (AD). These results revealed that the probe can be a valuable imaging tool for studying mGluR5-related diseases in the nervous system.

Exploring the Association between Cathepsin B and Parkinson's Disease.

OBJECTIVE: The aim of this study is to investigate the association between Cathepsin B and Parkinson's Disease (PD), with a particular focus on determining the role of N-acetylaspartate as a potential mediator. METHODS: We used summary-level data from Genome-Wide Association Studies (GWAS) for a two-sample Mendelian randomization (MR) analysis, exploring the association between Cathepsin B (3301 cases) and PD (4681 cases). A sequential two-step MR approach was applied (8148 cases) to study the role of N-acetylaspartate. RESULTS: The MR analysis yielded that genetically predicted elevated Cathepsin B levels correlated with a reduced risk of developing PD (p = 0.0133, OR: 0.9171, 95% CI: 0.8563-0.9821). On the other hand, the analysis provided insufficient evidence to determine that PD affected Cathepsin B levels (p = 0.8567, OR: 1.0035, 95% CI: 0.9666-1.0418). The estimated effect of N-acetylaspartate in this process was 7.52% (95% CI = -3.65% to 18.69%). CONCLUSIONS: This study suggested that elevated Cathepsin B levels decreased the risk of developing PD, with the mediation effect of N-acetylaspartate. Further research is needed to better understand this relationship.

The role of CELF family in neurodevelopment and neurodevelopmental disorders.

RNA-binding proteins (RBPs) bind to RNAs and are crucial for regulating RNA splicing, stability, translation, and transport. Among these proteins, the CUGBP Elav-like family (CELF) is a highly conserved group crucial for posttranscriptional regulation by binding to CUG repeats. Comprising CELF1-6, this family exhibits diverse expression patterns and functions. Dysregulation of CELF has been implicated in various neural disorders, encompassing both neurodegenerative and neurodevelopmental conditions, such as Alzheimer's disease and autism. This article aims to provide a comprehensive summary of the CELF family's role in neurodevelopment and neurodevelopmental disorders. Understanding CELF's mechanisms may offer clues for potential therapeutic strategies by regulating their targets in neurodevelopmental disorders.

Cascading Detection of Hydrogen Sulfide and N-Acetyltransferase 2 in Hepatocellular Carcinoma Cells Using a Two-Photon Fluorescent Probe.

Hydrogen sulfide (H2S), a critical gas signaling molecule, and N-acetyltransferase 2 (NAT2), a key enzyme in drug metabolism, are both known active biomarkers for liver function. However, the interactions and effects of H2S and NAT2 in living cells or lesion sites remain unknown due to the lack of imaging tools to achieve simultaneous detection of these two substances, making it challenging to implement real-time imaging and precise tracking. Herein, we report an activity-based two-photon fluorescent probe, TPSP-1, for the cascade detection of H2S and NAT2 in living liver cells. Continuous conversion from TPSP-1 to TPSP-3 was achieved in liver cells and tissues. Significantly, leveraging the outstanding optical properties of this two-photon fluorescent probe, TPSP-1, has been effectively used to identify pathological tissue samples directly from clinical liver cancer patients. This work provides us with this novel sensing and two-photon imaging probe, which can be used as a powerful tool to study the physiological functions of H2S and NAT2 and will help facilitate rapid and accurate diagnosis and therapeutic evaluation of hepatocellular carcinoma.

Oxygen self-supplying small size magnetic nanoenzymes for synergistic photodynamic and catalytic therapy of breast cancer.

In recent years, tumor catalytic therapy based on nanozymes has attracted widespread attention. However, its application is limited by the tumor hypoxic microenvironment (TME). In this study, we developed oxygen-supplying magnetic bead nanozymes that integrate hemoglobin and encapsulate the photosensitizer curcumin, demonstrating reactive oxygen species (ROS)-induced synergistic breast cancer therapy. Fe3O4 magnetic bead-mediated catalytic dynamic therapy (CDT) generates hydroxyl radicals (˙OH) through the Fenton reaction in the tumor microenvironment. The Hb-encapsulated Fe3O4 magnetic beads can be co-loaded with the photosensitizer/chemotherapeutic agent curcumin (cur), resulting in Fe3O4-Hb@cur. Under hypoxic conditions, oxygen molecules are released from Fe3O4-Hb@cur to overcome the TME hypoxia, resulting in comprehensive effects favoring anti-tumor responses. Upon near-infrared (NIR) irradiation, Fe3O4-Hb@cur activates the surrounding molecular oxygen to generate a certain amount of singlet oxygen (1O2), which is utilized for photodynamic therapy (PDT) in cancer treatment. Meanwhile, we validated that the O2 carried by Hb significantly enhances the intracellular ROS level, intensifying the catalytic therapy mediated by Fe3O4 magnetic beads and inflicting lethal damage to cancer cells, effectively inhibiting tumor growth. Therefore, significant in vivo synergistic therapeutic effects can be achieved through catalytic-photodynamic combination therapy.

Metabolomics on depression: A comparison of clinical and animal research.

BACKGROUND: Depression is a major cause of suicide and mortality worldwide. This study aims to conduct a systematic review to identify metabolic biomarkers and pathways for major depressive disorder (MDD), a prevalent subtype of clinical depression. METHODS: We searched for metabolomics studies on depression published between January 2000 and January 2023 in the PubMed and Web of Science databases. The reported metabolic biomarkers were systematically evaluated and compared. Pathway analysis was implemented using MetaboAnalyst 5.0. RESULTS: We included 26 clinical studies on MDD and 78 metabolomics studies on depressive-like animal models. A total of 55 and 77 high-frequency metabolites were reported consistently in two-thirds of clinical and murine studies, respectively. In the comparison between murine and clinical studies, we identified 9 consistently changed metabolites (tryptophan, tyrosine, phenylalanine, methionine, fumarate, valine, deoxycholic acid, pyruvate, kynurenic acid) in the blood, 1 consistently altered metabolite (indoxyl sulfate) in the urine and 14 disturbed metabolic pathways in both types of studies. These metabolic dysregulations and pathways are mainly implicated in enhanced inflammation, impaired neuroprotection, reduced energy metabolism, increased oxidative stress damage and disturbed apoptosis, laying solid molecular foundations for MDD. LIMITATIONS: Due to unavailability of original data like effect-size results in many metabolomics studies, a meta-analysis cannot be conducted, and confounding factors cannot be fully ruled out. CONCLUSIONS: This systematic review delineated metabolic biomarkers and pathways related to depression in the murine and clinical samples, providing opportunities for early diagnosis of MDD and the development of novel diagnostic targets.

Multi-Omics Characteristics of Ferroptosis Associated with Colon Adenocarcinoma Typing and Survival.

BACKGROUND: Ferroptosis, an iron-dependent form of cell death, plays a crucial role in the progression of various cancers, including colon adenocarcinoma (COAD). However, the multi-omics signatures relevant to ferroptosis regulation in COAD diagnosis remain to be elucidated. METHODS: The transcriptomic, miRNAomic, and methylomic profiles of COAD patients were acquired from the Cancer Genome Atlas (TCGA). Ferroptosis activity in these patients was determined, represented by a ferroptosis score (FS), using single-sample gene set enrichment analysis (ssGSEA) based on the expression of ferroptosis-related genes. RESULTS: Results showed that the COAD patients with high-FS displayed favorable survival outcomes and heightened drug sensitivity. They also exhibited an up-regulation of genes involved in immune-related pathways (e.g., tumor necrosis factor signaling pathway), suggesting a correlation between immunity and ferroptosis in COAD progression. Furthermore, three survival prediction models were established based on 10 CpGs, 12 long non-coding RNAs (lncRNAs), and 14 microRNAs (miRNAs), respectively. These models demonstrated high accuracy in predicting COAD survival, achieving areas under the curve (AUC) >0.7. The variables used in the three models also showed strong correlations at different omics levels and were effective at discriminating between high-FS and low-FS COAD patients (AUC >0.7). CONCLUSIONS: This study identified different DNA methylation (DNAm), lncRNA, and miRNA characteristics between COAD patients with high and low ferroptosis activity. Furthermore, ferroptosis-related multi-omics signatures were established for COAD prognosis and classification. These insights present new opportunities for improving the efficacy of COAD therapy.

Anomalous origin of the left suprarenal, inferior phrenic arteries and left ovarian artery in a human cadaver.

This report addresses three variants identified within a female cadaver. Specifically, these were an anomalous origin of the right suprarenal artery, an abnormal bilateral ovarian vein branch, and a arterial tortuosity of the left ovarian artery. Indeed, the cadaver evinced abnormal origins in the case of the middle suprarenal artery (MSA), right inferior phrenic artery (IPA), and the renal capsule artery (emanating from the right renal artery). The MSA and IPA shared a common trunk with the inferior suprarenal artery. It was additionally observed that the right ovarian vein anastomoses the branches from the right kidney posterior inferior along with those to the renal fat capsule. Abnormal origin was evident in the case of the left ovarian artery, and arterial tortuosity was apparent in the lower region of the vessels. This report addresses both the clinical import of these variations and their likely causes. In the subdiaphragmatic region, surgical success and prognosis may be impacted by such anomalies; accordingly surgeons must be aware of anatomical variants of the ovarian and suprarenal arteries.

The New Role of HNF1A-NAS1/miR-214/INHBA Signaling Axis in Colorectal Cancer.

BACKGROUND: Colorectal cancer (CRC) is the third most common cancer and one of the leading causes of death worldwide. Seriously threatens human life and health. Previous studies have identified that inhibin ßA (INHBA) could induce tumorgenesis and progression of CRC through the regulation of the TGF-ß/Smad signal axis. The abnormal expression of INHBA is related to the poor prognosis of patients. The aim of this study was to identify the molecular mechanism of HNF1A-AS1 and miR-214 regulating INHBA and carcinogenesis through bioinformatics combined with experiments. METHODS: The expression of HNF1A-AS1, miRNA-214-5p, INHBA in pan-cancer and CRC were investigated in the Cancer Genome Atlas (TCGA). The correlation between HNF1A-AS1 and immune-related genes or miRNAs was explored via the Gene Expression Profiling Interactive Analysis (GEPIA) and volcano plots, respectively. The association between HNF1A-AS1 and differentially expressed miRNAs was constructed by TargetScan. The miRDB, miRWalk, and TargetScan databases were utilized to predict the target genes of hsa-miR-214. The expression of INHBA in tissues and cell lines of CRC was examined by RT-qPCR and western blot assay. RESULTS: The INHBA and HNF1A-AS1 expressions were increased in Colon adenocarcinoma (COAD) and Rectum adenocarcinoma (READ) of the TCGA database. Hsa-miR-214 was relatively less expressed in CRC tissues compared with para-cancer tissues. The expression of HNF1A-AS1 was negatively correlated with hsa-miR-214. INHBA was one of the target genes of hsa-miR-214 based on miRDB, miRWalk, and TargetScan databases. The specific binding sites of INHBA-3'UTR and miR-214-5p were identified by starBase. The expression level of INHBA was positively correlated with the T stage of tumor and negatively correlated with overall survival (OS) and disease-free survival (DFS) in CRC patients. The results of RT-qPCR and western blot indicated that the expression of INHBA in tissues and cell lines in CRC was higher than those in para-carcinoma tissues and normal colon cell lines, respectively. CONCLUSIONS: These findings suggested that HNF1A-AS1 and miRNA-214-5p were key upstream non-coding RNAs of INHBA. The HNF1A-AS1/miR-214/INHBA signal axis plays a significant role in the tumorgenesis and progression of CRC. By interfering with HNF1A-AS1 and INHBA genes on HT29 and SW480 cells, it was found that HNF1A-AS1 and INHBA genes may be important target genes in CRC.

Unraveling the prognostic significance and molecular characteristics of tumor-infiltrating B lymphocytes in clear cell renal cell carcinoma through a comprehensive bioinformatics analysis.

Introduction: Clear cell renal cell carcinoma (ccRCC) is a prevalent subtype of kidney cancer that exhibits a complex tumor microenvironment, which significantly influences tumor progression and immunotherapy response. In recent years, emerging evidence has underscored the involvement of tumor-infiltrating B lymphocytes (TIL-Bs), a crucial component of adaptive immunity, and their roles in ccRCC as compared to other tumors. Therefore, the present study endeavors to systematically explore the prognostic and molecular features of TIL-Bs in ccRCC. Methods: Initially, xCell algorithm was used to predict TIL-Bs in TCGA-KIRC and other ccRCC transcriptomic datasets. The Log-Rank test and Cox regression were applied to explore the relationship of B-cells with ccRCC survival. Then, we used WGCNA method to identify important modules related to TIL-Bs combining Consensus subcluster and scRNA-seq data analysis. To narrow down the prospective biomarkers, a prognostic signature was proposed. Next, we explored the feature of the signature individual genes and the risk-score. Finally, the potential associations of signature with clinical phenotypes and drugs were investigated. Results: Preliminary, we found ccRCC survival was negatively associated with TIL-Bs, which was confirmed by other datasets. Afterwards, ten co-expression modules were identified and a distinct ccRCC cluster was subsequently detected. Moreover, we assessed the transcriptomic alteration of B-cell in ccRCC and a relevant B-cell subtype was also pinpointed. Based on two core modules (brown, red), a 10-gene signature (TNFSF13B, SHARPIN, B3GAT3, IL2RG, TBC1D10C, STAC3, MICB, LAG3, SMIM29, CTLA4) was developed in train set and validated in test sets. These biomarkers were further investigated with regards to their differential expression and correlation with immune characteristics, along with risk-score related mutations and pathways. Lastly, we established a nomogram combined tumor grade and discovered underlying drugs according to their sensitivity response. Discussion: In our research, we elucidated the remarkable association between ccRCC and B-cells. Then, we detected several key gene modules, together with close patient subcluster and B-cell subtype,which could be responsible for the TIL-Bs in ccRCC. Moreover, we proposed a 10-gene signature and investigated its molecular features from multiple perspectives. Overall, understanding the roles of TIL-Bs could aid in the immunotherapeutic approaches for ccRCC, which deserve further research to clarify the implications for patient prognosis and treatment.

A high-field cellular DNP-supported solid-state NMR approach to study proteins with sub-cellular specificity.

Studying the structural aspects of proteins within sub-cellular compartments is of growing interest. Dynamic nuclear polarization supported solid-state NMR (DNP-ssNMR) is uniquely suited to provide such information, but critically lacks the desired sensitivity and resolution. Here we utilize SNAPol-1, a novel biradical, to conduct DNP-ssNMR at high-magnetic fields (800 MHz/527 GHz) inside HeLa cells and isolated cell nuclei electroporated with [13C,15N] labeled ubiquitin. We report that SNAPol-1 passively diffuses and homogenously distributes within whole cells and cell nuclei providing ubiquitin spectra of high sensitivity and remarkably improved spectral resolution. For cell nuclei, physical enrichment facilitates a further 4-fold decrease in measurement time and provides an exclusive structural view of the nuclear ubiquitin pool. Taken together, these advancements enable atomic interrogation of protein conformational plasticity at atomic resolution and with sub-cellular specificity.

Locally advanced rectal cancer with dMMR/MSI-H may be excused from surgery after neoadjuvant anti-PD-1 monotherapy: a multiple-center, cohort study.

Objective: Examine patients with locally advanced rectal cancer (LARC) with deficient mismatch repair (dMMR) or microsatellite instability-high (MSI-H) who received neoadjuvant immunotherapy (nIT), and compare the outcomes of those who chose a watch-and-wait (WW) approach after achieving clinical complete response (cCR) or near-cCR with those who underwent surgery and were confirmed as pathological complete response (pCR). Methods: LARC patients with dMMR/MSI-H who received nIT were retrospectively examined. The endpoints were 2-year overall survival (OS), 2-year disease-free survival (DFS), local recurrence (LR), and distant metastasis (DM). The efficacy of programmed cell death protein-1 (PD-1) inhibitor, immune-related adverse events (irAEs), surgery-related adverse events (srAEs), and enterostomy were also recorded. Results: Twenty patients who received a PD-1 inhibitor as initial nIT were examined. Eighteen patients (90%) achieved complete response (CR) after a median of 7 nIT cycles, including 11 with pCR after surgery (pCR group), and 7 chose a WW strategy after evaluation as cCR or near-cCR (WW group). Both groups had median follow-up times of 25.0 months. Neither group had a case of LR or DM, and the 2-year DFS and OS in each group was 100%. The two groups had similar incidences of irAEs (P=0.627). In the pCR group, however, 2 patients (18.2%) had permanent colostomy, 3 (27.3%) had temporary ileostomy, and 2 (18.2%) had srAEs. Conclusion: Neoadjuvant PD-1 blockade had high efficacy and led to a high rate of CR in LARC patients with dMMR/MSI-H. A WW strategy appears to be a safe and reliable option for these patients who achieve cCR or near-cCR after nIT.

Efficient 18.8 T MAS-DNP NMR reveals hidden side chains in amyloid fibrils.

Amyloid fibrils are large and insoluble protein assemblies composed of a rigid core associated with a cross-ß arrangement rich in ß-sheet structural elements. It has been widely observed in solid-state NMR experiments that semi-rigid protein segments or side chains do not yield easily observable NMR signals at room temperature. The reasons for the missing peaks may be due to the presence of unfavorable dynamics that interfere with NMR experiments, which result in very weak or unobservable NMR signals. Therefore, for amyloid fibrils, semi-rigid and dynamically disordered segments flanking the amyloid core are very challenging to study. Here, we show that high-field dynamic nuclear polarization (DNP), an NMR hyperpolarization technique typically performed at low temperatures, can circumvent this issue because (i) the low-temperature environment (~ 100 K) slows down the protein dynamics to escape unfavorable detection regime, (ii) DNP improves the overall NMR sensitivity including those of flexible side chains, and (iii) efficient cross-effect DNP biradicals (SNAPol-1) optimized for high-field DNP (≥ 18.8 T) are employed to offer high sensitivity and resolution suitable for biomolecular NMR applications. By combining these factors, we have successfully established an impressive enhancement factor of ε ~ 50 on amyloid fibrils using an 18.8 T/ 800 MHz magnet. We have compared the DNP efficiencies of M-TinyPol, NATriPol-3, and SNAPol-1 biradicals on amyloid fibrils. We found that SNAPol-1 (with ε ~ 50) outperformed the other two radicals. The MAS DNP experiments revealed signals of flexible side chains previously inaccessible at conventional room-temperature experiments. These results demonstrate the potential of MAS-DNP NMR as a valuable tool for structural investigations of amyloid fibrils, particularly for side chains and dynamically disordered segments otherwise hidden at room temperature.

Coupling of microplastic contamination in organisms and the environment: Evidence from the tidal flat ecosystem of Hangzhou Bay, China.

Microplastics are a new type of contaminant, widely defined as fragmented plastics with the longest dimension or diameter less than 5 mm, that are widely distributed, difficult to degrade, and easily adsorb other pollutants. Estuaries are key habitats where terrestrial microplastics flow in water runoff and import into the ocean. The ubiquitous use of plastics has resulted in a massive amount of plastic waste that is released and accumulated in bay ecosystems, posing serious ecological impacts. The study of microplastic contamination in Hangzhou Bay, the estuary of the Qiantang River, has important theoretical value in ecology and environmental science. Microplastic contamination in the tidal flats and organisms of Hangzhou Bay is serious and microplastic characteristics (type, size, and polymer type) in organisms were significantly correlated with those in the environmental media. Spatial autocorrelation was found in the abundance of microplastics in marine and tidal flat sediments of Hangzhou Bay, China, but no spatial autocorrelation was found in the sediment environment as a whole. The microplastic abundance in each organism in this study was not statistically correlated by weight or by individual count with its corresponding trophic level (P = 0.239 > 0.05; P = 0.492 > 0.05, respectively). Our study suggests a coupling relationship of microplastic contamination between organisms and the environment and can provide essential data and a scientific foundation for the study of microplastics pollution in Hangzhou Bay, as well as provide important evidence for the ecological and health risk assessment of microplastics.

Confining donor conformation distributions for efficient thermally activated delayed fluorescence with fast spin-flipping.

Fast spin-flipping is the key to exploit the triplet excitons in thermally activated delayed fluorescence based organic light-emitting diodes toward high efficiency, low efficiency roll-off and long operating lifetime. In common donor-acceptor type thermally activated delayed fluorescence molecules, the distribution of dihedral angles in the film state would have significant influence on the photo-physical properties, which are usually neglected by researches. Herein, we find that the excited state lifetimes of thermally activated delayed fluorescence emitters are subjected to conformation distributions in the host-guest system. Acridine-type flexible donors have a broad conformation distribution or bimodal distribution, in which some conformers feature large singlet-triplet energy gap, leading to long excited state lifetime. Utilization of rigid donors with steric hindrance can restrict the conformation distributions in the film to achieve degenerate singlet and triplet states, which is beneficial to efficient reverse intersystem crossing. Based on this principle, three prototype thermally activated delayed fluorescence emitters with confined conformation distributions are developed, achieving high reverse intersystem crossing rate constants greater than 106 s-1, which enable highly efficient solution-processed organic light-emitting diodes with suppressed efficiency roll-off.

The essential roles of small non-coding RNAs and RNA modifications in normal and malignant hematopoiesis.

Hematopoietic stem cells (HSCs) developing from mesoderm during embryogenesis are important for the blood circulatory system and immune system. Many factors such as genetic factors, chemical exposure, physical radiation, and viral infection, can lead to the dysfunction of HSCs. Hematological malignancies (involving leukemia, lymphoma, and myeloma) were diagnosed in more than 1.3 million people globally in 2021, taking up 7% of total newly-diagnosed cancer patients. Although many treatments like chemotherapy, bone marrow transplantation, and stem cell transplantation have been applied in clinical therapeutics, the average 5-year survival rate for leukemia, lymphoma, and myeloma is about 65%, 72%, and 54% respectively. Small non-coding RNAs play key roles in a variety of biological processes, including cell division and proliferation, immunological response and cell death. With the development of technologies in high-throughput sequencing and bioinformatic analysis, there is emerging research about modifications on small non-coding RNAs, as well as their functions in hematopoiesis and related diseases. In this study, we summarize the updated information of small non-coding RNAs and RNA modifications in normal and malignant hematopoiesis, which sheds lights into the future application of HSCs into the treatment of blood diseases.

Single-cell sequencing reveals the immune microenvironment landscape related to anti-PD-1 resistance in metastatic colorectal cancer with high microsatellite instability.

BACKGROUND: The objective response rate of microsatellite instability-high (MSI-H) metastatic colorectal cancer (mCRC) patients with first-line anti-programmed cell death protein-1 (PD-1) monotherapy is only 40-45%. Single-cell RNA sequencing (scRNA-seq) enables unbiased analysis of the full variety of cells comprising the tumor microenvironment. Thus, we used scRNA-seq to assess differences among microenvironment components between therapy-resistant and therapy-sensitive groups in MSI-H/mismatch repair-deficient (dMMR) mCRC. Resistance-related cell types and genes identified by this analysis were subsequently verified in clinical samples and mouse models to further reveal the molecular mechanism of anti-PD-1 resistance in MSI-H or dMMR mCRC. METHODS: The response of primary and metastatic lesions to first-line anti-PD-1 monotherapy was evaluated by radiology. Cells from primary lesions of patients with MSI-H/dMMR mCRC were analyzed using scRNA-seq. To identify the marker genes in each cluster, distinct cell clusters were identified and subjected to subcluster analysis. Then, a protein‒protein interaction network was constructed to identify key genes. Immunohistochemistry and immunofluorescence were applied to verify key genes and cell marker molecules in clinical samples. Immunohistochemistry, quantitative real-time PCR, and western blotting were performed to examine the expression of IL-1ß and MMP9. Moreover, quantitative analysis and sorting of myeloid-derived suppressor cells (MDSCs) and CD8+ T cells were performed using flow cytometry. RESULTS: Tumor responses in 23 patients with MSI-H/dMMR mCRC were evaluated by radiology. The objective response rate was 43.48%, and the disease control rate was 69.57%. ScRNA-seq analysis showed that, compared with the treatment-resistant group, the treatment-sensitive group accumulated more CD8+ T cells. Experiments with both clinical samples and mice indicated that infiltration of IL-1ß-driven MDSCs and inactivation of CD8+ T cells contribute to anti-PD-1 resistance in MSI-H/dMMR CRC. CONCLUSIONS: CD8+ T cells and IL-1ß were identified as the cell type and gene, respectively, with the highest correlation with anti-PD-1 resistance. Infiltration of IL-1ß-driven MDSCs was a significant factor in anti-PD-1 resistance in CRC. IL-1ß antagonists are expected to be developed as a new treatment for anti-PD-1 inhibitor resistance.

Design and Simulated Electrical Properties of a Proposed Implanted-Epi Silicon 3D-Spherical Electrode Detector.

A new type of 3D electrode detector, named here as the Implanted-Epi Silicon 3D-Spherical Electrode Detector, is proposed in this work. Epitaxial and ion implantation processes can be used in this new detector, allowing bowl-shaped electrodes to penetrate the silicon completely. The distance between the bowl cathode and the central collection electrode is basically the same, thus the total depletion voltage of Implanted-Epi Silicon 3D-Spherical Electrode Detectors is no longer directively correlated with the thickness of the silicon wafer, but only related to the electrode spacing. In this work, we model the device physics of this new structure and use a simulation program to conduct a systematic 3D simulation of its electrical characteristics, including electric potential and electric field distributions, electron concentration profile, leakage current, and capacitance, and compare it to the traditional 3D detectors. The theoretical and simulation study found that the internal electric potential of the new detector was smooth and no potential saddle point was found. The electric field is also uniform, and there is no zero field and a low electric field area. Compared with the traditional silicon 3D electrode detectors, the full depletion voltage is greatly reduced and the charge collection efficiency is improved. As a large electrode spacing (up to 500 µm) can be realized in the Implanted-Epi Silicon 3D-Spherical Electrode Detector thanks to their advantage of a greatly reduced full depletion voltage, detectors with large pixel cells (and thus small dead volume) can be developed for applications in photon science (X-ray, among others).

Effects of mowing on Pb accumulation and transport in Cynodon dactylon (L.) Pers.

Bermudagrass is a perennial herb with the potential to remediate Pb pollution in soils, and it has mechanical resistance to shearing. However, the effects of mowing on Pb absorption and accumulation in bermudagrass are still unclear. In this study, we investigated the effects of different quantities (0, 1, 2, 4 applications) of mowing treatments under 200 mg L-1 Pb application on Pb accumulation and transport in bermudagrass and explored the related mechanisms. Compared to the Pb treatment, all of the mowing treatments greatly decreased root Pb concentration/accumulation, significantly enhanced Pb concentrations/accumulations in stubble stems and stubble leaves, and ultimately promoted Pb enrichment and transport. Of the treatments in this study, two applications of mowing best promoted Pb enrichment, and four applications of mowing best promoted Pb transport efficiency. Furthermore, mowing mediated the microdistribution and physiological patterns of Pb in bermudagrass and affected the Pb transport by changing the subcellar distribution patterns and chemical forms of Pb in various tissues. Additionally, mowing promoted the transport of all mineral elements and showed a synergistic relationship with Pb absorption and transport. The change in mineral element metabolism patterns may be an important reason why mowing promoted Pb accumulation in bermudagrass. Our study provides the first comprehensive evidence regarding mowing facilitating the absorption, accumulation and transport of Pb in bermudagrass. Moderate mowing may be an effective strategy to assist in soil Pb remediation using bermudagrass.