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Background: The failure of novel therapies effective in preclinical animal models largely reflects the fact that current models do not really mimic the pathological/therapeutic features of glioblastoma (GBM), in which the most effective temozolomide chemoradiotherapy (RT/TMZ) regimen can only slightly extend survival. How to improve RT/TMZ efficacy remains a major challenge in clinic. Methods: Syngeneic G422TN-GBM model mice were subject to RT/TMZ, surgery, piperlongumine (PL), αPD1, glutathione. Metabolomics or transcriptomics data from G422TN-GBM and human GBM were used for gene enrichment analysis and estimation of ROS generation/scavenging balance, oxidative stress damage, inflammation and immune cell infiltration. Overall survival, bioluminescent imaging, immunohistochemistry, and immunofluorescence staining were used to examine therapeutic efficacy and mechanisms of action. Results: Here we identified that glutathione metabolism was most significantly altered in metabolomics analysis upon RT/TMZ therapies in a truly refractory and reliable mouse triple-negative GBM (G422TN) preclinical model. Consistently, ROS generators/scavengers were highly dysregulated in both G422TN-tumor and human GBM. The ROS-inducer PL synergized surgery/TMZ, surgery/RT/TMZ or RT/TMZ to achieve long-term survival (LTS) in G422TN-mice, but only one LTS-mouse from RT/TMZ/PL therapy passed the rechallenging phase (immune cure). Furthermore, the immunotherapy of RT/TMZ/PL plus anti-PD-1 antibody (αPD1) doubled LTS (50%) and immune-cured (25%) mice. Glutathione completely abolished PL-synergistic effects. Mechanistically, ROS reduction was associated with RT/TMZ-resistance. PL restored ROS level (mainly via reversing Duox2/Gpx2), activated oxidative stress/inflammation/immune responses signature genes, reduced cancer cell proliferation/invasion, increased apoptosis and CD3+/CD4+/CD8+ T-lymphocytes in G422TN-tumor on the basis of RT/TMZ regimen. Conclusion: Our findings demonstrate that PL reverses RT/TMZ-reduced ROS and synergistically resets tumor microenvironment to cure GBM. RT/TMZ/PL or RT/TMZ/PL/αPD1 exacts effective immune cure in refractory GBM, deserving a priority for clinical trials. [ABSTRACT FROM AUTHOR]

A visible‐light‐driven and room temperature photo‐Wolff‐Kischner reaction of sulfur ylides and N‐tosylhydrazones has been developed for the first time to provide modular access to alkene synthesis. The high functional group tolerance and broad substrate scope were demonstrated by more than 60 examples. Both E‐ and Z‐olefinic stereochemistry in the products could be controlled with excellent stereoselectivity. A series of mechanistic studies support that the reaction should proceed through a radical‐carbanion crossover pathway, specifically involving addition of photo‐generated sulfur ylide radical cations to N‐tosylhydrazones to form carbanions and subsequent Wolff‐Kischner process. [ABSTRACT FROM AUTHOR]

The 2,3‐dihydrobenzofuran ring systems are a privileged class of oxygen heterocycles, and their synthesis continues to attract considerable effort. Herein, a visible‐light‐driven photoredox‐catalyzed radical multicomponent cyclization of 2‐vinyl phenols, N‐alkoxypyridinium salts, and sulfur ylides is described. The key to the reaction success involves the use of both N‐alkoxypyridinium salts and sulfur ylides as radical precursors. This redox‐neutral protocol features good functional group tolerance, easily available starting materials, simple operation, and mild reaction conditions, enabling the modular synthesis of various 2,3‐disubstituted dihydrobenzofurans. Mechanistic studies have also elucidated some of the aspects associated with the key radical intermediates. [ABSTRACT FROM AUTHOR]

Low-cost formate salt was used as the reductant and part of the carboxyl source in a visible-light-driven dicarboxylation of diverse alkenes, including simple styrenes. The highly competing hydrocarboxylation side reaction was successfully overridden. Good yields of products were obtained under mild reaction conditions at ambient temperature and pressure of CO 2 . The dual role of formate salt may stimulate the discovery of a range of new transformations under mild and friendly conditions., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Objective: To investigate the frequency, karyotype characteristics and prognosis significance of monosomal karyotype (MK) in newly diagnosed MDS patients., Methods: The clinical, laboratorial and follow-up data of 202 MDS patients received the chromosome karyotype test in Department of Hematology, Ningbo Hospital of Zhejiang University from 2009 to 2018 were analyzed retrospectively, the monosomal karyotype features, clinical characteristics and their effects on the prognosis of MDS patients also were analyzed., Results: Among 202 cases of MDS, 25 (12.38%) confirmed to be the MK. The abnormality of chromosome 5 (60.00%), 7 (56.00%), 17 (56.00%), 15 (56.00%), 13 (40.00%) and 20（40.00%）were common in monosomal karyotype. MK + -MDS (MDS with monosomal karyotype) patients had higher bone marrow blast percentage than MK - -MDS (MDS without monosomal karyotype) patients, the median are 6.25% and 3.00% (P＜0.01) respectively, but there were no difference in age, sex, hemoglobin level, white blood cell count, neutrophile granulocyte percentage, platelet count, blood blast percentage, serum ferritin, folic acid and vitaminB12 between MK + -MDS and MK - -MDS. The overall survival time of MK + -MDS and MK - -MDS patiens with chromosome 3, 5, 7, 13, 15, 17 abnormalities was significantly shorter than MK - -MDS and AK+MK - -MDS patients (MDS with abnormal karyotype but without monosomal karyotype) , the MK + -MDS patients had a median survival time of 7.33 months, but the median survival time had not been reached in MK - -MDS and AK+MK - -MDS patients had not been reached by the end of the follow-up, and could not be assessed (P＜0.01)., Conclusion: The monosomal karyotype is a poor prognosis factor for newly-diagnosed MDS patients. The poor prognosis suggested by monosomal karyotype may be related with the abnormality of 3, 5, 7, 13, 15 and 17 chromosome.