Bacterial topoisomerase IV (ParE) is essential for DNA replication and serves as an attractive target for antibacterial drug development. The X-ray structure of the N-terminal 24 kDa ParE, ...responsible for ATP binding has been solved. Due to the accessibility of structural information of ParE, many potent ParE inhibitors have been discovered. In this study, a pyridylurea lead molecule against ParE of Escherichia coli (eParE) was characterized with a series of biochemical and biophysical techniques. More importantly, solution NMR analysis of compound binding to eParE provides better understanding of the molecular interactions between the inhibitor and eParE.
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•An N-terminal 24 kDa region of ParE from Escherichia coli (eParE) was obtained.•A bis-pyridylurea inhibitor exhibits an IC50 of 705 nM against eParE.•1H and 19F NMR confirmed eParE and inhibitor interactions.•Inhibitor binds to ATP binding site.
The atypical protein kinase C-iota (PKC-ι) enzyme is implicated in various cancers and has been put forward as an attractive target for developing anticancer therapy. A high concentration biochemical ...screen identified pyridine fragment weakly inhibiting PKC-ι with IC50 = 424 μM. Driven by structure–activity relationships and guided by docking hypothesis, the weakly bound fragment was eventually optimized into a potent inhibitor of PKC-ι (IC50= 270 nM). Through the course of the optimization, an intermediate compound was crystallized with the protein, and careful analysis of the X-ray crystal structure revealed a unique binding mode involving the post-kinase domain (C-terminal tail) of PKC-ι.
Biomarker studies using immunohistochemical (IHC) staining have not been successful for advanced hepatocellular carcinoma (HCC). We aimed to examine whether the tissue procurement process influences ...the protein expression levels detected by IHC.
Forty-two tissue pairs of HCC that had been both preoperatively biopsied and then surgically resected were included in the study. IHC staining was used to determine expression of target molecules, all of which were graded according to the percentage of positively stained tumor cells. The expression of beta-catenin was analyzed according to the localization of positive staining.
Biopsied and surgically resected tissues exhibited dissimilar phosphorylated extracellular signal regulated kinase (p-ERK) and phosphorylated AKT expression levels (kappa=0.025 and 0.153, respectively). On the contrary, p53 exhibited similar expression levels, and beta-catenin exhibited similar staining localization patterns in biopsied and surgically resected tissues (kappa=0.729 and 0.654, respectively).
Biopsied HCC tissues and their corresponding resected HCC tissues have inconsistent IHC-detected ERK and AKT expressions.
The discovery of a novel series of multi-receptor tyrosine kinase inhibitor is disclosed.
A series of azulene-based derivatives were synthesized as potent inhibitors for receptor tyrosine kinases ...such as FMS-like tyrosine kinase 3 (FLT-3). Systematic side chain modification of prototype
1a was carried out through SAR studies. Analogue
22 was identified from this series and found to be one of the most potent FLT-3 inhibitors, with good pharmaceutical properties, superior efficacy, and tolerability in a tumor xenograft model.
N-linked glycosylation of proteins is one of the post-translational modifications (PTMs) that shield tumor antigens from immune attack. Signaling lymphocytic activation molecule family 7 (SLAMF7) ...suppresses cancer cell phagocytosis and is an ideal target under clinical development. PTM of SLAMF7, however, remains less understood. In this study, we investigated the role of N-glycans on SLAMF7 in breast cancer progression. We identified seven N-linked glycosylation motifs on SLAMF7, which are majorly occupied by complex structures. Evolutionally conserved N98 residue is enriched with high mannose and sialylated glycans. Hyperglycosylated SLAMF7 was associated with STT3A expression in breast cancer cells. Inhibition of STT3A by a small molecule inhibitor, N-linked glycosylation inhibitor-1 (NGI-1), reduced glycosylation of SLAMF7, resulting in enhancing antibody affinity and phagocytosis. To provide an on-target effect, we developed an antibody-drug conjugate (ADC) by coupling the anti-SLAMF7 antibody with NGI-1. Deglycosylation of SLAMF7 increases antibody recognition and promotes macrophage engulfment of breast cancer cells. Our work suggests deglycosylation by ADC is a potential strategy to enhance the response of immunotherapeutic agents.
BackgroundThe resuscitation guidelines indicate pre-arrival dispatcher-assisted telephone CPR (DATCPR) instructions and measurement to increase the proportion of bystander CPR (BCPR), however the ...impact of those guidelines on survival is not well known.ObjectiveTo describe the impact of a comprehensive bundle of DATCPR on BCPR and survival from OHCA in a horizontal computerized-aided dispatch (CAD) system.MethodsA centralize CAD system in a metropolitan EMS is studied. Routinely in system the time from call to ambulance dispatch should be within 60 seconds. The audio recordings of confirmed OHCAs were reviewed using a standardized format linked with EMS and hospital process and outcome data. The proportions of BCPR and survival six months after implementation (P1) of a bundle that included guideline-based protocol changes, staff training, computerized audit, feedback to providers and leadership rebuilt are compared with that of the same month period in the prior year as control group (P0), using regression analysis for statistics.ResultsThere were 1437 OHCAs 665 P0, 772 P1; 64% male, median age 62 (IQR47-74)(Table 1). The rate of BCPR went from 20.6% in P0 to 35.0% in P1 (p<0.001). Outcome of ROSC (return to spontaneous circulation) upon hospital arrival was significantly higher in P1 (10.4%) compared to P0 (6.6% p=0.037), as was good neurological outcome (CPC 1or25.5% in P1 vs. 2.6% in P0 p=0.029). Survival to hospital discharge was higher in P1 (8.3%, vs. P06.4%) but not statistically significant. After adjusting for witnessed arrest, shockable rhythms, age, sex, and pre-hospital time intervals, good neurological outcome were still significantly higher in P1 vs. P0 adjusted odds ratios2.1 (95% 1.1-4.4).ConclusionsThe implementation of a comprehensive bundle of DATCPR in a metropolitan horizontal dispatch system was associated with significant improvements in the rates of BCPR and good neurologic outcome after OHCA.
Perovskite Solar Cells
In article number 2300988, Lee, Hsieh, Lu, Lin, and co‐workers synthesized three star‐shaped cyclopentadithiophene derivatives, with or without fluorine atoms incorporated, and ...applied them as hole‐transporting materials in the fully scalable fabrication of perovskite solar cells (PSCs) using the thermal‐assisted bar‐coating method. The PSCs fabricated from such films delivered a high power conversion efficiency of 18.49% on a large scale with encouraging long‐term stability.
Figures 1 and 2 were incorrectly switched. (2013) Correction: A Hormone Receptor-Based Transactivator Bridges Different Binary Systems to Precisely Control Spatial-Temporal Gene Expression in ...Drosophila.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Abstract Background: Current tumor models face challenges in accurately replicating the intricate and dynamic conditions of the tumor microenvironment (TME), limiting predictions of drug efficacy in ...drug development and personalized treatment. Furthermore, the continuous and real-time observation of drug responses variations resulting from tumor heterogeneity poses challenges in existing models, including patient-derived organoids and animal models. To address these limitations, our study introduces a novel approach through a tumor-microenvironment-on-chip (TMoC) that combines 3D tissue cultivation and a circulation system, incorporating physiological gradients of oxygen and nutrients. Serving as a tool to faithfully replicate the intricate TME, TMoC facilitates highly accurate drug screening for enhanced therapeutic precision. Method: Based on organ-on-chip and microfluidic systems, our platform reconstructs the cellular heterogeneity of the TME using tumor tissue-dissociated cells in collagen I or Matrigel within a strip-shaped 3D cultivation space, enabling simple analysis of regional responses. A circulation system, powered by a peristaltic pump, aids medication and immune cell entry for combination immunotherapy assessment. Real-time apoptosis analysis via fluorescence microscopy and sample retrieval for in-depth analysis are enabled. In drug screening, TMoC results are compared with mouse model outcomes and medication records for various cancers and treatments. Result: TMoC reconstructed physiological-like gradients, including oxygen levels, and facilitated the infiltration of cytotoxic CD8+ T cells, providing a distinctive model for assessing the synergistic impact of immune checkpoint inhibitors and chemotherapy drugs. Additionally, tissues cultured in TMoC retained their original cellular composition. TMoC demonstrated efficacy in drug screening across various cancer models, including breast, pancreatic, and colorectal cancers. In clinical studies, tumor tissue-derived cells from patients were cultivated on the TMoC, and the treating results are subsequently compared with clinical outcomes. Whether in animal models or clinical cases, the drug screening outcomes of TMoC consistently aligned with in vivo drug responses. Conclusion: The TMoC offering a platform that modeling some complex characteristics of TME. With applications in drug screening and clinical studies, it shows promising correlations between TMoC and in vivo responses. Citation Format: Chiao-Min Lin, Hsaun-Yu Mu, Li-An Chu, Ya-Hui Lin, Ji Li, Chao-Yu Liu, Hsi-Chien Huang, Sheng-Liang Cheng, Tsung-Ying Lee, Hsin Mei Lee, Hsin-Min Chen, Yun-Jen Tsai, Tzu-Hung Hsiao, Kee-Ming Man, Yunching Chen, Jen-Huang Huang. Tumor-microenvironment-on-chip: an ex vivo drug screening platform enabling real-time observation of regional tumor responses during drug development and clinical treatments abstract. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6771.
Abstract Objectives: Mesenchymal-type colorectal cancer (CRC), characterized by strong stromal infiltration and immune tolerance, resists immune checkpoint blockade and has poor outcomes. ...Cancer-associated fibroblasts (CAFs), abundant in tumor stroma, actively remodel the extracellular matrix (ECM), modulate immune evasion, and drive tumor progression. We have recently identified thioredoxin domain-containing protein 5 (TXNDC5), a protein disulfide isomerase (PDI), as a critical mediator of fibroblast activation and ECM remodeling in organ fibrosis. We hypothesized that TXNDC5 could contribute to fibroblast activation, stroma formation and disease progression in cancer, especially in the stroma-enriched fibrogenic mesenchymal-type CRC. Methods: Transcriptome databases of CRC were re-analyzed to determine the clinical relevance of TXNDC5. Experimentally, CRC was induced in mouse lines by azoxymethane (AOM) and dextran sulfate sodium (DSS) stimuli, a model sharing multiple characteristics with human mesenchymal-type CRC. Human colonic fibroblast line CCD-18co was used to investigate the molecular mechanisms by which TXNDC5 regulates colonic fibroblast activities. Fibroblast-specific TXNDC5 knockout (Col1a2-Cre/ERT2*TXNDC5fl/fl) mice were generated, combining with single-cell RNA sequencing analyses on AOM/DSS-induced CRC tumors in these animals, to clarify how fibroblast TXNDC5 impact tumor microenvironment, CRC progression and response to immune checkpoint blockade. Findings: TXNDC5 was predominantly expressed in stromal fibroblasts of human and mouse CRC. Fibroblast-specific deletion of Txndc5 lessened CAF activation, attenuated tumor fibrosis and reduced tumor burden in AOM/DSS-induced CRC. Mechanistically, increased TXNDC5 levels augments TGFβ signaling in CAF by post-translational stabilization of TGFBR1 through its PDI activity. In addition, deletion of Txndc5 in CAFs led to less tumor desmoplasia, decompressed tumor vessels and attenuated intra-tumoral hypoxia, thereby easing immune tolerance and increasing cytotoxic T cell infiltration in CRC. Single-cell transcriptome analysis revealed a marked change of intra-tumoral immune cell populations upon fibroblast-specific deletion of TXNDC5, shifting from myeloid-derived suppressive cells to cytotoxic tumor-infiltrating lymphocytes. Importantly, depletion of TXNDC5 in CAFs potentiated the anti-tumor effects of immune checkpoint blockade with anti-PD1 therapy in CRC. Conclusions: Our data suggest an important yet previously unrecognized role of fibroblast TXNDC5 in CRC progression, through enhancing CAF activation, stroma formation and immune escape. Combining immune checkpoint blockade with TXNDC5 deletion synergistically improved anti-tumor effects in CRC. Targeting TXNDC5, therefore, can be a novel therapeutic approach for CRC patients. Citation Format: Kai-Lin Cheng, Chih-I Chen, Shu-Han Yu, Huai-Wen Liang, Yi-Wei Tsai, Chen-Ting Hung, Yu-Shan Lin, Yi-Shiuan Tzeng, Sung-Jan Lin, Yueh-Feng Wu, Jen-Kuang Lee, Chia-Hui Yu, Shuei-Liong Lin, Shih-Yu Chen, Tzu-Tang Wei, Yun-Ju Huang, Ruey-Hwa Chen, Ching-Chow Chen, Kai-Chien Yang. Targeting TXNDC5 in stromal fibroblasts resolves desmoplasia and resistance to immune checkpoint blockade in mesenchymal-type colorectal cancer abstract. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 285.
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