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1.
J Org Chem ; 89(4): 2741-2747, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38299344

RESUMO

Acyl radicals have been generated from the decarboxylation of α-oxocarboxylic acids by using a readily accessible organic pyrimidopteridine photoredox catalyst under ultraviolet-A (UV-A) light irradiation. These reactive acyl radicals were smoothly added to olefins such as styrenes and diverse Michael acceptors, with the assistance of H2O/D2O as hydrogen donors, enabling easy access to a diverse range of ketones/ß-deuterio ketones. A wide range of α-oxocarboxylic acids are compatible with this reaction, which shows a reliable, atom-economical, and eco-friendly protocol. Furthermore, postsynthetic diversifications and applications are presented.

2.
Chem Commun (Camb) ; 60(33): 4455-4458, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38563643

RESUMO

Herein, a novel and facile organic photosensitizer (thioxanthone)-mediated energy-transfer-enabled (EnT-enabled) dearomative [2+2] cycloaddition of aromatic heterocycles/maleimides for green synthesis of cyclobutane-fused polycyclic skeletons is reported. Mechanistic investigations revealed that different EnT pathways by triplet thioxanthone were initiated when different aromatic heterocycles participated in the reaction, giving the corresponding excited intermediates, which underwent the subsequent intermolecular [2+2] cycloaddition to access the desired highly functionalized cyclobutane-fused polycyclic skeletons.

3.
Clin Mol Hepatol ; 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39103994

RESUMO

Background: Intrahepatic cholangiocarcinoma (ICC) is a highly desmoplastic tumor with poor prognosis even after curative resection. We investigated the associations between the composition of the ICC stroma and immune cell infiltration and aimed to develop a stromal-immune signature to predict prognosis in surgically treated ICC. Patients and methods: We recruited 359 ICC patients and performed immunohistochemistry to detect α-smooth muscle actin (α-SMA), CD3, CD4, CD8, Foxp3, CD68, and CD66b. Aniline was used to stain collagen deposition. Survival analyses were performed to detect prognostic values of these markers. Recursive partitioning for a discrete-time survival tree was applied to define a stromal-immune signature with distinct prognostic value. We delineated an integrated stromal-immune signature based on immune cell subpopulations and stromal composition to distinguish subgroups with different recurrence-free survival (RFS) and overall survival (OS) time. Results: We defined four major patterns of ICC stroma composition according to the distributions of α-SMA and collagen: dormant (α-SMAlow/collagenhigh), fibrogenic (α-SMAhigh/collagenhigh), inert (α-SMAlow/collagenlow), and fibrolytic (α-SMAhigh/collagenlow). The stroma types were characterized by distinct patterns of infiltration by immune cells. We divided patients into six classes. Class I, characterized by high CD8 expression and dormant stroma, displayed the longest RFS and OS, whereas Class VI, characterized by low CD8 expression and high CD66b expression, displayed the shortest RFS and OS. The integrated stromal-immune signature was consolidated in a validation cohort. Conclusion: We developed and validated a stromal-immune signature to predict prognosis in surgically treated ICC. These findings provide new insights into the stromal-immune response to ICC.

4.
JAMA Netw Open ; 6(3): e231476, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36867406

RESUMO

Importance: BRAF variants are associated with tumor progression; however, the prevalence of BRAF variant subtypes and their association with disease characteristics, prognosis, and targeted therapy response in patients with intrahepatic cholangiocarcinoma (ICC) are largely unknown. Objective: To explore the association of BRAF variant subtypes with disease characteristics, prognosis, and targeted therapy response in patients with ICC. Design, Setting, and Participants: In this cohort study, 1175 patients who underwent curative resection for ICC from January 1, 2009, through December 31, 2017, were evaluated at a single hospital in China. Whole-exome sequencing, targeted sequencing, and Sanger sequencing were performed to identify BRAF variants. The Kaplan-Meier method and log-rank test were used to compare overall survival (OS) and disease-free survival (DFS). Univariate and multivariate analyses were performed using Cox proportional hazards regression. Associations between BRAF variants and targeted therapy response were tested in 6 BRAF-variant, patient-derived organoid lines and in 3 of the patient donors of those lines. Data were analyzed from June 1, 2021, to March 15, 2022. Interventions: Hepatectomy in patients with ICC. Main Outcomes and Measures: The association of BRAF variant subtypes with OS and DFS. Results: Of 1175 patients with ICC, the mean (SD) age was 59.4 (10.4) years and 701 (59.7%) were men. A total of 20 different subtypes of BRAF somatic variance affecting 49 patients (4.2%) were identified; V600E was the most frequent allele in this cohort, accounting for 27% of the identified BRAF variants, followed by K601E (14%), D594G (12%), and N581S (6%). Compared with patients with non-V600E BRAF variants, patients with BRAF V600E variants were more likely to have large tumor size (10 of 13 [77%] vs 12 of 36 [33%]; P = .007), multiple tumors (7 of 13 [54%] vs 8 of 36 [22%]; P = .04), and more vascular/bile duct invasion (7 of 13 [54%] vs 8 of 36 [22%]; P = .04). Multivariate analysis revealed that BRAF V600E variants, but not overall BRAF variants or non-V600E BRAF variants, were associated with poor OS (hazard ratio [HR], 1.87; 95% CI, 1.05-3.33; P = .03) and DFS (HR, 1.66; 95% CI, 1.03-2.97; P = .04). There were also broad differences among organoids with different BRAF variant subtypes in sensitivity to BRAF or MEK inhibitors. Conclusions and Relevance: The findings of this cohort study suggest that there are broad differences among organoids with different BRAF variant subtypes in sensitivity to BRAF or MEK inhibitors. Identifying and classifying BRAF variants may be able to help guide precise treatment for patients with ICC.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Proteínas Proto-Oncogênicas B-raf , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ductos Biliares Intra-Hepáticos , Estudos de Coortes , Quinases de Proteína Quinase Ativadas por Mitógeno , Prognóstico
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