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1.
Adv Mater ; : e2311283, 2024 Mar 15.
Article in English | MEDLINE | ID: mdl-38489768

ABSTRACT

Organ-selective drug delivery is expected to maximize the efficacy of various therapeutic modalities while minimizing their systemic toxicity. Lipid nanoparticles and polymersomes can direct the organ-selective delivery of mRNAs or gene editing machineries, but their delivery is limited to mostly liver, spleen, and lung. A platform that enables delivery to these and other target organs is urgently needed. Here, a library of glycocalyx-mimicking nanoparticles (GlyNPs) comprising five randomly combined sugar moieties is generated, and direct in vivo library screening is used to identify GlyNPs with preferential biodistribution in liver, spleen, lung, kidneys, heart, and brain. Each organ-targeting GlyNP hit show cellular tropism within the organ. Liver, kidney, and spleen-targeting GlyNP hits equipped with therapeutics effectively can alleviate the symptoms of acetaminophen-induced liver injury, cisplatin-induced kidney injury, and immune thrombocytopenia in mice, respectively. Furthermore, the differential organ targeting of GlyNP hits is influenced not by the protein corona but by the sugar moieties displayed on their surface. It is envisioned that the GlyNP-based platform may enable the organ- and cell-targeted delivery of therapeutic cargoes.

2.
BMC Cancer ; 24(1): 357, 2024 Mar 20.
Article in English | MEDLINE | ID: mdl-38509504

ABSTRACT

BACKGROUND: Biliary tract cancer (BTC) is a relatively rare but aggressive gastrointestinal cancer with a high mortality rate. Cancer stem cell (CSC) populations play crucial roles in tumor biology and are responsible for the low response to anti-cancer treatment and the high recurrence rate. This study investigated the role of Transgelin-2 (TAGLN2), overexpressed in CSC in BTC cells, and analyzed its expression in patient tissues and serum to identify potential new targets for BTC. METHODS: TAGLN2 expression was suppressed by small-interfering or short hairpin RNAs, and its effects on tumor biology were assessed in several BTC cell lines. Furthermore, the effects of TAGLN2 silencing on gemcitabine-resistant BTC cells, differentially expressed genes, proteins, and sensitivity to therapeutics or radiation were assessed. TAGLN2 expression was also assessed using western blotting and immunohistochemistry in samples obtained from patients with BTC to validate its clinical application. RESULTS: Suppression of TAGLN2 in BTC cell lines decreased cell proliferation, migration, invasion, and tumor size, in addition to a reduction in CSC features, including clonogenicity, radioresistance, and chemoresistance. TAGLN2 was highly expressed in BTC tissues, especially in cancer-associated fibroblasts in the stroma. Patients with a low stromal immunohistochemical index had prolonged disease-free survival compared to those with a high stromal immunohistochemical index (11.5 vs. 7.4 months, P = 0.013). TAGLN2 expression was higher in the plasma of patients with BTC than that in those with benign diseases. TAGLN2 had a higher area under the curve (0.901) than CA19-9, a validated tumor biomarker (0.799; P < 0.001). CONCLUSION: TAGLN2 plays a critical role in promoting BTC cell growth and motility and is involved in regulating BTC stemness. Silencing TAGLN2 expression enhanced cell sensitivity to radiation and chemotherapeutic drugs. The expression of TAGLN2 in patient tissue and plasma suggests its potential to serve as a secretory biomarker for BTC. Overall, targeting TAGLN2 could be an appropriate therapeutic strategy against advanced cancer following chemotherapy failure.


Subject(s)
Biliary Tract Neoplasms , Microfilament Proteins , Humans , Microfilament Proteins/genetics , Microfilament Proteins/metabolism , Muscle Proteins/genetics , Biomarkers, Tumor/genetics , Biomarkers, Tumor/metabolism , Biliary Tract Neoplasms/drug therapy , Biliary Tract Neoplasms/genetics , Cell Line, Tumor
3.
Front Chem ; 12: 1355636, 2024.
Article in English | MEDLINE | ID: mdl-38318111

ABSTRACT

Securinega alkaloids have intrigued chemists since the isolation of securinine in 1956. This family of natural products comprises a securinane subfamily with a piperidine substructure and norsecurinane alkaloids featuring a pyrrolidine core. From a biosynthetic perspective, the piperidine moiety in securinane alkaloids derives from lysine, whereas the pyrrolidine moiety in norsecurinane natural products originates from ornithine, marking an early biogenetic divergence. Herein, we introduce a single-atom deletion strategy that enables the late-stage conversion of securinane to norsecurinane alkaloids. Notably, for the first time, this method enabled the transformation of piperidine-based (allo)securinine into pyrrolidine-based (allo)norsecurinine. Straightforward access to norsecurinine from securinine, which can be readily extracted from the plant Flueggea suffruticosa, abundant across the Korean peninsula, holds promise for synthetic studies of norsecurinine-based oligomeric securinega alkaloids.

4.
Sci Rep ; 14(1): 2942, 2024 02 05.
Article in English | MEDLINE | ID: mdl-38316853

ABSTRACT

To identify risk factors and biomarker for early recurrence in patients diagnosed with pancreatic cancer who undergo curative resection. Early recurrence after curative resection of pancreatic cancer is an obstacle to long-term survival. We retrospectively reviewed 162 patients diagnosed with pancreatic cancer who underwent curative resection. Early recurrence was defined as recurrence within 12 months of surgery. We selected S100A2 as a biomarker and investigated its expression using immunohistochemistry. Of the total, 79.6% (n = 129) of patients received adjuvant chemotherapy after surgery and 117 (72.2%) experienced recurrence, of which 73 (45.1%) experience early recurrence. In multivariate analysis, age < 60 years, presence of lymph node metastasis, and no adjuvant chemotherapy were significantly associated with early recurrence (all P < 0.05). The proportion of patients with high S100A2 expression (H-score > 5) was significantly lower in the early recurrence group (41.5% vs. 63.3%, P = 0.020). The cumulative incidence rate of early recurrence was higher in patients with an S100A2 H-score < 5 (41.5% vs. 63.3%, P = 0.012). The median overall survival of patients with higher S100A2 expression was longer than those with lower S100A2 expression (median 30.1 months vs. 24.2 months, P = 0.003). High-risk factors for early recurrence after surgery for pancreatic cancer include young age, lymph node metastasis, and no adjuvant therapy. Neoadjuvant treatment or intensive adjuvant therapy after surgery may improve the prognosis of patients with high-risk signatures. In patients who receive adjuvant therapy, high S100A2 expression is a good predictor.


Subject(s)
Pancreatic Neoplasms , Humans , Middle Aged , Retrospective Studies , Lymphatic Metastasis , Prognosis , Pancreatic Neoplasms/pathology , Chemotherapy, Adjuvant , Biomarkers , Neoplasm Recurrence, Local/pathology
5.
Genome Med ; 16(1): 20, 2024 Jan 31.
Article in English | MEDLINE | ID: mdl-38297291

ABSTRACT

BACKGROUND: Recent studies using single-cell transcriptomic analysis have reported several distinct clusters of neoplastic epithelial cells and cancer-associated fibroblasts in the pancreatic cancer tumor microenvironment. However, their molecular characteristics and biological significance have not been clearly elucidated due to intra- and inter-tumoral heterogeneity. METHODS: We performed single-cell RNA sequencing using enriched non-immune cell populations from 17 pancreatic tumor tissues (16 pancreatic cancer and one high-grade dysplasia) and generated paired spatial transcriptomic data from seven patient samples. RESULTS: We identified five distinct functional subclusters of pancreatic cancer cells and six distinct cancer-associated fibroblast subclusters. We deeply profiled their characteristics, and we found that these subclusters successfully deconvoluted most of the features suggested in bulk transcriptome analysis of pancreatic cancer. Among those subclusters, we identified a novel cancer cell subcluster, Ep_VGLL1, showing intermediate characteristics between the extremities of basal-like and classical dichotomy, despite its prognostic value. Molecular features of Ep_VGLL1 suggest its transitional properties between basal-like and classical subtypes, which is supported by spatial transcriptomic data. CONCLUSIONS: This integrative analysis not only provides a comprehensive landscape of pancreatic cancer and fibroblast population, but also suggests a novel insight to the dynamic states of pancreatic cancer cells and unveils potential therapeutic targets.


Subject(s)
Carcinoma, Pancreatic Ductal , Pancreatic Neoplasms , Humans , Transcriptome , Carcinoma, Pancreatic Ductal/genetics , Pancreatic Neoplasms/genetics , Pancreatic Neoplasms/pathology , Gene Expression Profiling , Prognosis , Tumor Microenvironment/genetics , Single-Cell Analysis , DNA-Binding Proteins/genetics , Transcription Factors/genetics
6.
Gastrointest Endosc ; 99(2): 214-223.e4, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37598866

ABSTRACT

BACKGROUND AND AIMS: Pancreatic steatosis (PS) may be a risk factor for acute pancreatitis. Whether it is also a risk factor for post-ERCP pancreatitis (PEP) has not been evaluated. This study aimed to determine the impact of PS on PEP development. METHODS: This multicenter prospective trial enrolled 786 consecutive patients who underwent contrast-enhanced abdominal CT and subsequent first-time ERCP. PS was evaluated based on pancreatic attenuation on unenhanced CT images. The risk of PS for the development of PEP was evaluated using a logistic regression model. RESULTS: Of 527 patients included in the study, 157 (29.8%) had PS and 370 (70.2%) did not. At 24 hours after ERCP, there was a significant difference in the PEP identified in 22 patients (14.0%) in the PS group and 23 patients (6.2%) in the "no PS" (NPS) group (P = .017). Diabetes and hypertension were more common in the PS group than in the NPS group; no differences in dyslipidemia were found. Patients with PS had a higher risk for the development of PEP than those with NPS (odds ratio, 2.09; 95% confidence interval, 1.08-4.03). No other variables were identified as risk factors for PEP. CONCLUSIONS: PS is a significant risk factor for PEP for which preventive measures should be considered. Standardized measurement protocols to assess PS by CT are needed. (Clinical trial registration number: KCT0006068.).


Subject(s)
Pancreatitis , Humans , Acute Disease , Cholangiopancreatography, Endoscopic Retrograde/adverse effects , Pancreatitis/epidemiology , Pancreatitis/etiology , Pancreatitis/prevention & control , Prospective Studies , Risk Factors , Tomography, X-Ray Computed
7.
Gut Liver ; 18(1): 184-191, 2024 Jan 15.
Article in English | MEDLINE | ID: mdl-37317559

ABSTRACT

Background/Aims: Endoscopic ultrasound-guided fine-needle aspiration/biopsy (EUS-FNA/B) is essential in diagnosing solid pancreatic lesions (SPLs), but without rapid on-site evaluation (ROSE), a repeat EUS-FNA/B is crucial for clarifying an inconclusive diagnosis. We aimed to evaluate factors associated with improved diagnostic performance of repeat EUS-FNA/B for initially inconclusive SPL diagnoses without ROSE. Methods: Of 5,894 patients subjected to EUS-FNA/B, 237 (4.0%) with an initially inconclusive diagnosis of SPLs were retrospectively enrolled from five tertiary medical centers between January 2016 and June 2021. Diagnostic performance and procedural factors of EUS-FNA/B were analyzed. Results: The diagnostic accuracies of first and repeat EUS-FNA/B were 96.2% and 67.6%, respectively. Of 237 patients with an inconclusive diagnosis from initial EUS-FNA/B, 150 were pathologically diagnosed after repeat EUS-FNA/B. In multivariate analysis of repeat EUS-FNA/B, tumor location (body/tail vs head: odds ratio [OR], 3.74; 95% confidence interval [CI], 1.48 to 9.46), number of needle passes (≥4 vs ≤3: OR, 4.80; 95% CI, 1.44 to 15.99), needle type (FNB vs FNA: OR, 3.26; 95% CI, 1.44 to 7.36), needle size (22 gauge vs 19/20 gauge: OR, 2.35; 95% CI, 1.19 to 4.62), and suction method (suction vs others: OR, 5.19; 95% CI, 1.30 to 20.75) were associated with a significantly improved diagnostic performance. Conclusions: Repeat EUS-FNA/B is essential for patients with an inconclusive EUS-FNA/B without ROSE. To improve the diagnostic performance of repeated EUS-FNA/B, it is recommended that 22-gauge FNB needles, ≥4 needle passes, and suction methods are used.


Subject(s)
Endoscopic Ultrasound-Guided Fine Needle Aspiration , Pancreatic Neoplasms , Humans , Endoscopic Ultrasound-Guided Fine Needle Aspiration/methods , Retrospective Studies , Pancreas/diagnostic imaging , Pancreas/pathology , Suction , Multivariate Analysis , Pancreatic Neoplasms/diagnostic imaging , Pancreatic Neoplasms/pathology
8.
Am J Gastroenterol ; 119(1): 183-190, 2024 Jan 01.
Article in English | MEDLINE | ID: mdl-37713527

ABSTRACT

INTRODUCTION: The incidence of postendoscopic retrograde cholangiopancreatography (ERCP) infections is reported to be up to 18% in patients with biliary obstruction. Antibiotic prophylaxis may reduce the risk of infectious complications after ERCP; however, the clinical value of prophylactic antibiotics in ERCP remains controversial. METHODS: We conducted a double-blind, placebo-controlled, randomized trial to investigate whether the use of prophylactic antibiotics would reduce infectious complications after ERCP in patients with biliary obstruction. We randomly assigned patients in a 1:1 ratio to receive either a single dose of 1 g intravenous cefoxitin or normal saline as a placebo 30 minutes before undergoing ERCP. The primary outcome was the incidence of infectious complications after ERCP. RESULTS: We enrolled 378 patients, and 189 patients were assigned to each group. The risk of infectious complications after ERCP was 2.8% (5 of 176 patients) in the antibiotic prophylaxis group and 9.8% (17 of 173 patients) in the placebo group (risk ratio, 0.29; 95% confidence interval [CI], 0.11-0.74, P = 0.0073). The incidence rates of bacteremia were 2.3% (4 of 176 patients) and 6.4% (11 of 173 patients), respectively (risk ratio, 0.36; 95% CI, 0.12-1.04; P = 0.0599). The incidence rate of cholangitis was 1.7% (3 of 176 patients) in the antibiotic prophylaxis group and 6.4% (11 of 173 patients) in the placebo group (risk ratio, 0.27; 95% CI, 0.08-0.87; P = 0.0267). DISCUSSION: Antibiotic prophylaxis before ERCP in patients with biliary obstruction resulted in a significantly lower risk of infectious complications, especially cholangitis, than placebo ( ClinicalTrials.gov trial number NCT02958059).


Subject(s)
Cholangitis , Cholestasis , Humans , Cholangiopancreatography, Endoscopic Retrograde/adverse effects , Antibiotic Prophylaxis/adverse effects , Cholestasis/prevention & control , Cholestasis/complications , Cholangitis/epidemiology , Cholangitis/etiology , Cholangitis/prevention & control , Anti-Bacterial Agents/therapeutic use
9.
Biochim Biophys Acta Biomembr ; 1866(1): 184218, 2024 01.
Article in English | MEDLINE | ID: mdl-37634858

ABSTRACT

Transportan 10 (TP10) is a 21-residue, cationic, α-helical cell-penetrating peptide that can be used as a delivery vector for various bioactive molecules. Based on recent confocal microscopy studies, it is believed that TP10 can translocate across neutral lipid membrane passively, possibly as a monomer, without the formation of permanent pore. Here, we performed extensive molecular dynamics (MD) simulations of TP10W (Y3W variant of TP10) to find the microscopic details of binding, folding and insertion of TP10W to transmembrane state in POPC bilayer. Binding study with CHARMM36 force field showed that TP10W initially binds to the membrane surface in unstructured configuration, but it spontaneously folds into α-helical conformation under the lipid head groups. Further insertion of TP10W, changing from a surface bound state to a vertically oriented transmembrane state, was investigated via umbrella simulations. The resulting free energy profile shows a relatively small barrier between two states, suggesting a possible translocation pathway as a monomer. In fact, unbiased simulation of transmembrane TP10W revealed how a charged Lys side chain can move from one leaflet to the other without a significant free energy cost. Finally, we compared the results of TP10W simulations with those of point mutated variants (TP10W-K12A18 and TP10W-K19L) to understand the effect of charge distribution on the peptide. It was observed that such a conservative mutation can cause noticeable changes in the conformations of both surface bound and transmembrane states. The results of present study will be discussed in relation to the experimentally observed activities of TP10W against neutral membrane.


Subject(s)
Cell-Penetrating Peptides , Cell-Penetrating Peptides/chemistry , Molecular Dynamics Simulation , Recombinant Fusion Proteins , Lipids
10.
Yonsei Med J ; 65(1): 34-41, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38154478

ABSTRACT

PURPOSE: Cannulation of the major papilla is the most challenging part of endoscopic retrograde cholangiopancreatography (ERCP) for which physician-controlled wire-guided cannulation (PCWGC) and assistant-controlled wire-guided cannulation (ACWGC) are used as the cannulation techniques. PCWGC can reportedly save up to about 30% of the labor cost by reducing the number of assistants. This study aims to compare the safety and efficacy of PCWGC and ACWGC. MATERIALS AND METHODS: Of the 2151 patients aged >20 years (4193 cases) who underwent ERCP at Yonsei University Medical Center between January 2015 and December 2016, 989 were included in this study. RESULTS: Among efficacy outcomes, cannulation success rate, rate of precut sphincterotomy (PCWGC vs. ACWGC: 21.3% vs. 25.9%), bile duct cannulation time (PCWGC vs. ACWGC: median 3.0 minutes vs. 3.6 minutes), and total procedure time (PCWGC vs. ACWGC: median 13.6 minutes vs. 13.1 minutes) were not significantly different. Among safety outcomes, lower rates of post-ERCP pancreatitis were observed with PCWGC than with ACWGC (PCWGC vs. ACWGC: 5.8% vs. 8.8%, p=0.128). Among other post-ERCP adverse events (bleeding, perforation, and cholangitis), the difference was not significant between the groups. Radiation exposure (total dose area product, PCWGC vs. ACWGC: median 1979.9 µGym² vs. 2062.0 µGym², p=0.194) and ERCP cost excluding labor cost (PCWGC vs. ACWGC: $1576 vs. $1547, p=0.606) were not significantly different. CONCLUSION: Requiring less assistants, PCWGC showed comparable efficacy and safety to ACWGC. PCWGC can be considered as an alternative option, especially in facilities lacking manpower and resources.


Subject(s)
Cholangiopancreatography, Endoscopic Retrograde , Physicians , Humans , Cholangiopancreatography, Endoscopic Retrograde/adverse effects , Catheterization/adverse effects , Catheterization/methods , Sphincterotomy, Endoscopic/adverse effects , Sphincterotomy, Endoscopic/methods , Hemorrhage/etiology
11.
Gut Liver ; 2023 Dec 22.
Article in English | MEDLINE | ID: mdl-38130162

ABSTRACT

Background/Aims: : Palliative chemotherapy (PC) is not standardized for patients with advanced ampulla of Vater adenocarcinoma (AA). This multicenter, retrospective study evaluated first-line PC outcomes in patients with AA. Methods: : Patients diagnosed with AA between January 2010 and December 2020 who underwent PC were enrolled from 10 institutions. Overall survival (OS) and progression-free survival (PFS) according to the chemotherapy regimen were analyzed. Results: : Of 255 patients (mean age, 64.0±10.0 years; male, 57.6%), 14 (5.5%) had locally advanced AA and 241 (94.5%) had metastatic AA. Gemcitabine plus cisplatin (GP) was administered as first-line chemotherapy to 192 patients (75.3%), whereas capecitabine plus oxaliplatin (CAPOX) was administered to 39 patients (15.3%). The median OS of all patients was 19.8 months (95% confidence interval [CI], 17.3 to 22.3), and that of patients who received GP and CAPOX was 20.4 months (95% CI, 17.2 to 23.6) and 16.0 months (95% CI, 11.2 to 20.7), respectively. The median PFS of GP and CAPOX patients were 8.4 months (95% CI, 7.1 to 9.7) and 5.1 months (95% CI, 2.5 to 7.8), respectively. PC for AA demonstrated improved median outcomes in both OS and PFS compared to conventional bile duct cancers that included AA. Conclusions: : While previous studies have shown mixed prognostic outcomes when AA was analyzed together with other biliary tract cancers, our study unveils a distinct clinical prognosis specific to AA on a large scale with systemic anticancer therapy. These findings suggest that AA is a distinct type of tumor, different from other biliary tract cancers, and AA itself could be expected to have a favorable response to PC.

12.
Commun Chem ; 6(1): 252, 2023 Nov 16.
Article in English | MEDLINE | ID: mdl-37973829

ABSTRACT

Coordination complexes, particularly metalloproteins, highlight the significance of metal-sulfur bonds in biological processes. Their unique attributes inspire efforts to synthetically reproduce these intricate metal-sulfur motifs. Here, we investigate the synthesis and characterization of copper(I)-thioether coordination complexes derived from copper(I) halides and the chiral cyclic ß-amino acid trans-4-aminotetrahydrothiophene-3-carboxylic acid (ATTC), which present distinctive structural properties and ligand-to-metal ratios. By incorporating ATTC as the ligand, we generated complexes that feature a unique chiral conformation and the capacity for hydrogen bonding, facilitating the formation of distinct geometric structures. Through spectroscopic analyses and density functional theory (DFT) calculations, we studied the complexes' optical properties, including their emission bands and variable second-harmonic generation (SHG) efficiencies, which vary based on the halide used. Our findings underscore the potential of the ATTC ligand in creating unusual coordination complexes and pave the way for further investigations into their potential applications, particularly within materials science.

13.
Front Oncol ; 13: 1206565, 2023.
Article in English | MEDLINE | ID: mdl-37736542

ABSTRACT

Objective: Early chemoresistance and tumor mass progression are associated with poor prognosis in pancreatic ductal adenocarcinoma (PDAC). Circulating tumor cells (CTCs) have been studied as potential predictors of treatment response and prognosis in PDAC; however, this approach has yet to be applied in clinical practice. The aim of our study was to investigate the phenotypic characteristics of CTCs and determine their predictive value for PDAC progression. Methods: We prospectively enrolled 40 patients who were pathologically diagnosed with PDAC and collected blood samples at diagnosis, 2 months after diagnosis, and during disease progression or recurrence. We used a microfabricated filter-based enrichment system to retrieve and analyze CTCs, which were classified using immunofluorescence staining (CD45, EpCAM, and vimentin). Results: Our study included 20 women and 20 men (median age, 66 years). Overall, 45% of the patients (18/40) had disseminated disease, and 77.5% (31/40) received chemotherapy. Multivariate analysis revealed that the total CTC count and carbohydrate antigen 19-9 level at 2 months after diagnosis were associated with disease progression (P<0.05). Linear mixed model analysis revealed that the total CTC count and vimentin-positive CTCs were significantly correlated with treatment response during chemotherapy (P=0.024 and 0.017, respectively). Kaplan-Meier analysis showed that total CTC positivity at 2 months was significantly associated with poor progression-free survival (P=0.038). Conclusion: Our study's findings suggest that CTCs can serve as predictive biomarkers of clinical outcomes in patients with PDAC receiving palliative chemotherapy. In particular, the total CTC count and vimentin-positive CTCs showed changes associated with the chemotherapy response.

14.
Adv Mater ; 35(52): e2305753, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37722669

ABSTRACT

Designing chiral channels in organic frameworks presents an ongoing challenge due to the intricate control of size, shape, and functionality required. A novel approach is presented, which crafts enantiomeric chiral channels in metal-peptide networks (MPNs) by integrating short foldamer ligands with CuI clusters. The MPN structure serves as a 3D blueprint for host-guest chemistry, fostering modular substitution to refine chiral channel properties at the atomic scale. Incorporating hydrogen bond networks augments guest molecule interactions with the channel surface. This approach expedites enantiomer discrimination in racemic mixtures and incites adaptable guest molecules to take on specific axially chiral conformations. Distinct from traditional metal-organic frameworks (MOFs) and conventional reticular architectures, this foldamer-based methodology provides a predictable and customizable host-guest interaction system within a 3D topology. This innovation sets the stage for multifunctional materials that merge host-guest interaction systems with metal-complex properties, opening up potential applications in catalysis, sensing, and drug delivery.

15.
Angew Chem Int Ed Engl ; 62(39): e202305196, 2023 09 25.
Article in English | MEDLINE | ID: mdl-37309575

ABSTRACT

We introduce a novel cyclic ß-amino acid, trans-(3S,4R)-4-aminotetrahydrothiophene-3-carboxylic acid (ATTC), as a versatile building block for designing peptide foldamers with controlled secondary structures. We synthesized and characterized a series of ß-peptide hexamers containing ATTC using various techniques, including X-ray crystallography, circular dichroism, and NMR spectroscopy. Our findings reveal that ATTC-containing foldamers can adopt 12-helical conformations similar to their isosteres and offer the possibility of fine-tuning their properties via post-synthetic modifications. In particular, chemoselective conjugation strategies demonstrate that ATTC provides unique post-synthetic modification opportunities, which expand their potential applications across diverse research areas. Collectively, our study highlights the versatility and utility of ATTC as an alternative to previously reported cyclic ß-amino acid building blocks in both structural and functional aspects, paving the way for future research in the realm of peptide foldamers and beyond.


Subject(s)
Peptides , Sulfides , Peptides/chemistry , Protein Structure, Secondary , Magnetic Resonance Spectroscopy , Amino Acids/chemistry , Crystallography, X-Ray
16.
Angew Chem Int Ed Engl ; 62(34): e202304815, 2023 08 21.
Article in English | MEDLINE | ID: mdl-37310766

ABSTRACT

Common medications for treating inflammatory bowel disease (IBD) have limited therapeutic efficacy and severe adverse effects. This underscores the urgent need for novel therapeutic approaches that can effectively target inflamed sites in the gastrointestinal tract upon oral administration, exerting potent therapeutic efficacy while minimizing systemic effects. Here, we report the construction and in vivo therapeutic evaluation of a library of anti-inflammatory glycocalyx-mimicking nanoparticles (designated GlyNPs) in a mouse model of IBD. The anti-inflammatory GlyNP library was created by attaching bilirubin (BR) to a library of glycopolymers composed of random combinations of the five most naturally abundant sugars. Direct in vivo screening of 31 BR-attached anti-inflammatory GlyNPs via oral administration into mice with acute colitis led to identification of a candidate GlyNP capable of targeting macrophages in the inflamed colon and effectively alleviating colitis symptoms. These findings suggest that the BR-attached GlyNP library can be used as a platform to identify anti-inflammatory nanomedicines for various inflammatory diseases.


Subject(s)
Colitis , Inflammatory Bowel Diseases , Nanoparticles , Animals , Mice , Glycocalyx , Colitis/drug therapy , Inflammatory Bowel Diseases/drug therapy , Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/therapeutic use
17.
Sci Rep ; 13(1): 7300, 2023 05 05.
Article in English | MEDLINE | ID: mdl-37147417

ABSTRACT

Gallbladder stones (GS) is associated with an increased risk of cardiovascular disease. However, the relationship between cholecystectomy for GS and acute coronary syndrome (ACS) is unknown. We investigated the ACS risk in patients with GS and its association with cholecystectomy. Data from the Korean National Health Insurance Service-National Sample Cohort from 2002 to 2013 was extracted. Overall, 64,370 individuals were selected through a 1:3 propensity score matching. Patients were stratified into two groups for comparison: the gallstone group, GS patients with or without cholecystectomy; and the control group, patients without GS or cholecystectomy. The gallstone group exhibited a higher risk of ACS than the control group (hazard ratio [HR], 1.30; 95% confidence interval [CI] 1.15-1.47; P < 0.0001). In the gallstone group, individuals without cholecystectomy had a higher risk of ACS development (HR: 1.35, 95% CI 1.17-1.55, P < 0.0001). Patients with GS with diabetes, hypertension, or dyslipidemia, had a higher risk of developing ACS than GS patients without the metabolic diseases (HR: 1.29, P < 0.001). The risk did not significantly differ after cholecystectomy compared to those without GS (HR: 1.15, P = 0.1924), but without cholecystectomy, the risk of ACS development was significantly higher than control group (1.30, 95% CI 1.13-1.50, P = 0.0004). Among patients without above metabolic disorders, cholecystectomy was still associated with increased ACS risk in the gallstone group (HR: 2.93, 95% CI 1.27-6.76, P = 0.0116). GS increased the risk of ACS. The effect of cholecystectomy on ACS risk differs according to the presence or absence of metabolic disorders. Thus, the decision to perform cholecystectomy for GS should consider both the ACS risk and the underlying disorders.


Subject(s)
Acute Coronary Syndrome , Diabetes Mellitus , Gallstones , Humans , Gallstones/complications , Gallstones/epidemiology , Gallstones/surgery , Cohort Studies , Acute Coronary Syndrome/epidemiology , Acute Coronary Syndrome/surgery , Acute Coronary Syndrome/complications , Cholecystectomy/adverse effects , Risk Factors
18.
J Am Coll Surg ; 237(3): 501-512, 2023 09 01.
Article in English | MEDLINE | ID: mdl-37222437

ABSTRACT

BACKGROUND: The role of adjuvant chemotherapy (AC) in patients with ampullary adenocarcinoma (AA) remains controversial. This study aimed to determine if AC could improve the prognosis of patients with resected AA. STUDY DESIGN: This study enrolled patients diagnosed with AA at 9 tertiary teaching hospitals. Patients who did and did not receive AC were matched 1:1 using propensity score. The overall survival (OS) and recurrence-free survival (RFS) were compared between the 2 groups. RESULTS: Of the 1,057 patients with AA, 883 underwent curative-intent pancreaticoduodenectomy, and 255 received AC. Because patients with advanced-stage AA received AC more frequently, the no AC group unexpectedly had a longer OS (not reached vs 78.6 months; p < 0.001) and RFS (not reached vs 18.7 months; p < 0.001) than did the AC group in the unmatched cohort. In the propensity score-matched cohort (n = 296), no difference between the 2 groups in terms of OS (95.9 vs 89.8 months, p = 0.303) and RFS (not reached vs 25.5 months; p = 0.069) was found. By subgroup analysis, patients with advanced stage (pT4 or pN1-2) showed longer OS in the AC group than in the no AC group (not reached vs 15.7 months, p = 0.007: 89.8 vs 24.2 months, p = 0.006, respectively). There was no difference in RFS according to AC in the propensity score-matched cohort. CONCLUSIONS: Given its favorable long-term outcomes, AC can be recommended for patients with resected AA, especially those in the advanced stage (pT4 or pN1-2).


Subject(s)
Adenocarcinoma , Ampulla of Vater , Common Bile Duct Neoplasms , Pancreatic Neoplasms , Humans , Chemotherapy, Adjuvant , Adenocarcinoma/drug therapy , Adenocarcinoma/surgery , Common Bile Duct Neoplasms/drug therapy , Common Bile Duct Neoplasms/surgery , Cohort Studies , Retrospective Studies
19.
Gastroenterology ; 165(1): 133-148.e17, 2023 Jul.
Article in English | MEDLINE | ID: mdl-36907523

ABSTRACT

BACKGROUND & AIMS: Pancreatic ductal adenocarcinoma (PDA), with its highly metastatic propensity, is one of the most lethal subtypes of pancreatic cancer. Although recent large-scale transcriptomic studies have demonstrated that heterogeneous gene expressions play an essential role in determining molecular phenotypes of PDA, biological cues for and consequences of distinct transcriptional programs remain unclear. METHODS: We developed an experimental model that enforces the transition of PDA cells toward a basal-like subtype. We combined epigenome and transcriptome analyses with extensive in vitro and in vivo evaluations of tumorigenicity to demonstrate the validity of basal-like subtype differentiation in association with endothelial-like enhancer landscapes via TEA domain transcription factor 2 (TEAD2). Finally, we used loss-of-function experiments to investigate the importance of TEAD2 in regulating reprogrammed enhancer landscape and metastasis in basal-like PDA cells. RESULTS: Aggressive characteristics of the basal-like subtype are faithfully recapitulated in vitro and in vivo, demonstrating the physiological relevance of our model. Further, we showed that basal-like subtype PDA cells acquire a TEAD2-dependent proangiogenic enhancer landscape. Genetic and pharmacologic inhibitions of TEAD2 in basal-like subtype PDA cells impair their proangiogenic phenotypes in vitro and cancer progression in vivo. Last, we identify CD109 as a critical TEAD2 downstream mediator that maintains constitutively activated JAK-STAT signaling in basal-like PDA cells and tumors. CONCLUSIONS: Our findings implicate a TEAD2-CD109-JAK/STAT axis in the basal-like differentiated pancreatic cancer cells and as a potential therapeutic vulnerability.


Subject(s)
Carcinoma, Pancreatic Ductal , Pancreatic Neoplasms , Humans , Pancreatic Neoplasms/pathology , Carcinoma, Pancreatic Ductal/pathology , Pancreas/pathology , Cell Differentiation , Gene Expression Regulation, Neoplastic , TEA Domain Transcription Factors , Pancreatic Neoplasms
20.
Phys Chem Chem Phys ; 25(10): 7466-7476, 2023 Mar 08.
Article in English | MEDLINE | ID: mdl-36848062

ABSTRACT

With the introduction of artificial peptides as antimicrobial agents and organic catalysts, numerous efforts have been made to design foldamers with desirable structures and functions. Computational tools are a helpful proxy for revealing the dynamic structures at atomic resolution and understanding foldamer's complex structure-function relationships. However, the performance of conventional force fields in predicting the structures of artificial peptides has not been systematically evaluated. In this study, we critically assessed three popular force fields, AMBER ff14SB, CHARMM36m, and OPLS-AA/L, in predicting conformational propensities of a ß-peptide foldamer at monomer and hexamer levels. Simulation results were compared to those obtained from quantum chemistry calculations and experimental data. We also utilised replica exchange molecular dynamics simulations to investigate the energy landscape of each force field and assess the similarities and differences between force fields. We compared different solvent systems in the AMBER ff14SB and CHARMM36m frameworks and confirmed the unanimous role of hydrogen bonds in shaping energy landscapes. We anticipate that our data will pave the way for further improvements to force fields and for understanding the role of solvents in peptide folding, crystallisation, and engineering.


Subject(s)
Amino Acids , Molecular Dynamics Simulation , Crystallization , Hydrogen Bonding , Peptides , Solvents
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