Regiodivergent Hydrosilylation of Polar Enynes to Synthesize Site-Specific Silyl-Substituted Dienes.

Herein, we present catalyst-regulated switchable site-selective hydrosilylation of enynes, which are suitable for a wide range of alkyl and aryl substituted polar enynes and exhibit excellent functional group compatibility. Under the optimized conditions, silyl groups can be precisely installed at various positions of 1,3-dienes. While α- and γ-silylation products were obtained under platinum-catalytic systems, ß-silylation products were delivered with [Cp*RuCl]4 as catalyst. This process lead to the formation of 1,3-dienoates with diverse substitutions, which would pose challenges with other methodologies.

Biotoxicity of Halide Perovskites in Mice.

Halide perovskites are crystalline semiconductors with exceptional optoelectronic properties, rapidly developing toward large-scale applications. Lead (II) (Pb2+ ) is the core element used to prepare halide perovskites. Pb2+ can displace key 2+ elements, including calcium, zinc and iron, that regulate vital physiological functions. Sn2+ can replace Pb2+ within the perovskite structure and, if accidentally dispersed in the environment, it readily oxidizes to Sn4+ , which is compatible with physiological functions and thus potentially safe. The 3+ salt bismuth (III) (Bi3+ ) is also potentially safe for the same reason and useful to prepare double perovskites. Here, this work studies the biotoxicity of Pb, Sn, and Bi perovskites in mice for the first time. This work analyses histopathology and growth of mice directly exposed to perovskites and investigate the development of their offspring generation. This study provides the screening of organs and key physiological functions targeted by perovskite exposure to design specific studies in mammalians.

Synthesis and Transformation of Bis(silyl)-Substituted Conjugated Vinylallene Compounds.

We develop a copper-catalyzed disilylation of polysubstituted pent-1-en-4-yn-3-yl acetate derivatives, which in one pot furnishes the bis(silyl)-substituted vinylallenes in moderate yields under mild reaction conditions. The reaction shows broad substrate scope and single stereoselectivity. Besides, we develop a method to decrease the electrocyclization temperature of vinylallenes for the synthesis of methylenecyclobutenes by installing bis(silyl) substituents. And the effect of a silyl substituent on electrocyclization of vinylallenes was studied via DFT computation. The synthetic method features broad substrate scope and excellent stereoselectivity.

Regio- and enantioselective CuH-catalyzed 1,2- and 1,4-hydrosilylation of 1,3-enynes.

We report a copper-catalyzed ligand-controlled selective 1,2- and 1,4-hydrosilylation of 1,3-enynes, which furnishes enantiomerically enriched propargyl- and 1,2-allenylsilane products in high yields with excellent enantioselectivities (up to 99% ee). This reaction proceeds under mild conditions, shows broad substrate scope for both 1,3-enynes and trihydrosilanes, and displays excellent regioselectivities. Mechanistic studies based on deuterium-labeling reactions and density functional theory (DFT) calculations suggest that allenylcopper is the dominant reactive intermediate under both 1,2- and 1,4-hydrosilylation conditions, and it undergoes metathesis with silanes via selective four-membered or six-membered transition state, depending on the nature of the ligand. The weak interactions between the ligands and the reacting partners are found to be the key controlling factor for the observed regioselectivity switch. The origin of high enantiocontrol in the 1,4-hydrosilylation is also revealed by high level DLPNO-CCSD(T) calculations.

Synthesis of (E)-2-(1-(methoxyimino)ethyl)-2-phenylbenzofuran-3(2H)-ones from (E)-1-(benzofuran-2-yl)ethan-1-one O-methyl oximes and iodobenzenes via a palladium-catalyzed dearomative arylation/oxidation reaction.

A new method has been successfully developed that offers a facile and reliable approach for synthesizing (E)-2-(1-(methoxyimino)ethyl)-2-phenylbenzofuran-3(2H)-one, providing 28 compounds. This optimized process enables efficient preparation of a wide range of compounds using readily available (E)-1-(benzofuran-2-yl)ethan-1-one O-methyl oxime and iodobenzene, and provides alternative ideas for the structural modification of benzofuran ketones.

The Proliferative Role of Immune Checkpoints in Tumors: Double Regulation.

Cancer remains a serious social health problem, and immunotherapy has become the major treatments in tumor treatment. Additionally, improving the efficiency and safety of treatment is necessary. Further, more therapy targets are warranted for future tumor treatments. In this review, in addition to examining the currently recognized role of immune regulation, we focus on the proliferative role of 15 immune checkpoints in various tumors, including PD1, PD-L1, FGL1, CD155, CD47, SIRPα, CD276, IDO1, SIGLEC-15, TIM3, Galectin-9, CD70, CD27, 4-1BBL, and HVEM. We managed to conclude that various immune checkpoints such as PD1/PD-L1, FGL1, CD155, CD47/SIRPα, CD276, and SIGLEC-15 all regulate the cell cycle, and specifically through Cyclin D1 regulation. Furthermore, a variety of signal pathways engage in proliferation regulation, such as P13K, AKT, mTOR, and NK-κB, which are also the most common pathways involved in the regulation of immune checkpoint proliferation. Currently, only PD1/PD-L1, CD47/SIRPα, TIM3/Galectin-9, and CD70/CD27 checkpoints have been shown to interact with each other to regulate tumor proliferation in pairs. However, for other immune checkpoints, the role of their receptors or ligands in tumor proliferation regulation is still unknown, and we consider the enormous potential in this area. An increasing number of studies have validated the various role of immune checkpoints in tumors, and based on this literature review, we found that most of the immune checkpoints play a dual regulatory role in immunity and proliferation. Therefore, the related pathways in proliferation regulation can served the role of therapy targets in tumor therapy. Further, great potential is displayed by IDO1, SIGLEC-15, 4-1BBL, and HVEM in tumor proliferation regulation, which may become novel therapy targets in tumor treatment.

Dual immunological and proliferative regulation of immune checkpoint FGL1 in lung adenocarcinoma: The pivotal role of the YY1-FGL1-MYH9 axis.

Rational: Lung cancer is the most common tumor worldwide, with the highest mortality rate and second highest incidence. Immunotherapy is one of the most important treatments for lung adenocarcinoma (LUAD); however, it has relatively low response rate and high incidence of adverse events. Herein, we explored the therapeutic potential of fibrinogen-like protein 1 (FGL1) for LUAD. Methods: Data from GEPIA and ACLBI databases were assessed to explore gene-gene correlations and tumor immune infiltration patterns. A total of 200 patients with LUAD were recruited. FGL1 levels in the serum and cellular supernatant were determined by enzyme-linked immunosorbent assay. In vitro and in vivo experiments were performed to assess the effect FGL1 on the proliferation of LUAD cells. Cocultures were performed to explore the effect of FGL1 knockdown in lung cancer cells on T cells, concerning cytokine secretion and viability. PROMO and hTFtarget databases were used for transcription factor prediction. Quantitative polymerase chain reaction (qPCR), chromatin immunoprecipitation, and dual luciferase reporter assays were performed to validate the identified transcription factor of FGL1. Immunoprecipitation, mass spectrometry and gene ontology analysis were performed to explore the downstream partners of FGL1. Results: FGL1 expression in LUAD was positively associated with PDL1, but not for PD1 expression. Moreover, FGL1 was positively associated with the CD3D expression and negatively associated with FOXP3, S100A9, and TPSB2 within the tumor site. FGL1 promotes the secretion of interleukin-2 by T cells in vitro, simultaneously inducing their apoptosis. Indeed, YY1 is the upstream molecule of FGL1 was found to be transcriptionally regulated by YY1 and to directly by to MYH9 to promote the proliferation of LUAD cells in vitro and in vivo. Conclusions: FGL1 is involved in the immunological and proliferative regulation of LUAD cells by controlling the secretion of important immune-related cytokines via the YY1-FGL1-MYH9 axis. Hence, targeting FGL1 in LUAD may pave the way for the development of new immunotherapies for tackling this malignancy.

IGSF11 and VISTA: a pair of promising immune checkpoints in tumor immunotherapy.

Immunotherapy has become the major treatment for tumors in clinical practice, but some intractable problems such as the low response rate and high rates of immune-related adverse events still hinder the progress of tumor immunotherapy. Hence, it is essential to explore additional immunotherapy treatment targets. In this review, we focus on the structure, expression and expression-related mechanisms, interactions, biological functions and the progress in preclinical/clinical research of IGSF11 and VISTA in tumors. We cover the progress in recent research with this pair of immune checkpoints in tumor immune regulation, proliferation, immune resistance and predictive prognosis. Both IGSF11 and VISTA are highly expressed in tumors and are modulated by various factors. They co-participate in the functional regulation of immune cells and the inhibition of cytokine production. Besides, in the downregulation of IGSF11 and VISTA, both inhibit the growth of some tumors. Preclinical and clinical trials all emphasize the predictive role of IGSF11 and VISTA in the prognosis of tumors, and that the predictive role of the same gene varies from tumor to tumor. At present, further research is proving the enormous potential of IGSF11 and VISTA in tumors, and especially the role of VISTA in tumor immune resistance. This may prove to be a breakthrough to solve the current clinical immune resistance, and most importantly, since research has focused on VISTA but less on IGSF11, IGSF11 may be the next candidate for tumor immunotherapy.

The downregulation of fibrinogen-like protein 1 inhibits the proliferation of lung adenocarcinoma via regulating MYC-target genes.

Background: The mechanisms involved in the malignant progression of lung adenocarcinoma (LUAD) are still inconclusive. Fibrinogen-like protein 1 (FGL1) and LAG3 are a pair of immune checkpoints that create an inhibitory immune microenvironment in tumors. However, other roles of FGL1 in LUAD have not been extensively studied. Our study aims to explore the role of FGL1 in the malignant progression of LUAD and to provide new therapeutic targets and strategies for LUAD treatment. Methods: Differential gene expression of FGL1 was analyzed using the Gene Expression Profiling Interactive Analysis (GEPIA), Oncomine, UALCAN, and Gene Expression Omnibus (GEO) databases. A pan-cancer analysis was conducted using the Oncomine, TIMER, and UALCAN databases. A total of 140 tumor tissues and paired normal tissues were collected, IHC and immunofluorescence staining were used to explore the expression of FGL1. GeneMANIA database and STRING database were used to analyze gene-gene interaction and protein-protein interaction, respectively. A mutation analysis was conducted using the cBioPortal database, and an immune infiltration analysis was conducted using the TIMER database. A survival analysis was carried out using the GEPIA and PrognoScan database. The knockdown of FGL1 was confirmed by western blot (WB) and immunofluorescence staining. Cell proliferation was tested by cell cycle analysis and real-time cell analysis. RNA sequencing (RNA-seq) was used to explore the differential genes of FGL1 knockdown in LUAD cells. Results: Multiple databases showed that FGL1 was highly expressed in LUAD. The results of IHC indicated that FGL1 was highly expressed in the cytoplasm of LUAD cells. FGL1 was negatively associated with immune infiltration in LUAD. The main mutation of FGL1 is deep deletion, the altered group and high expression group indicated poor prognosis. The downregulation of FGL1 lead to a significantly decreased percentage of PC9 cells in S phase, but had little effect on the proliferation of Jurkat T cells. RNA-seq and GSEA analysis indicated that the differential genes were mainly enriched in MYC-target genes, which suggested that the downregulation of FGL1 inhibited cell proliferation by regulating MYC-target genes. Conclusions: FGL1 exerts in LUAD proliferation in addition to immune regulation. The downregulation of FGL1 inhibits the proliferation of LUAD cells by regulating MYC-target genes. Thus, FGL1 may be a novel therapeutic target in LUAD.

A New Esophagogastric Anastomosis for McKeown Esophagectomy in Esophageal Cancer.

For McKeown esophagectomy, hand-sewn and mechanical esophagogastric anastomosis techniques have been improved for constructing esophagogastrostomy. However, postoperative anastomosis-related complication rates remain high in patients undergoing cervical anastomosis. Here, we report an original and reliable hand-sewn cervical tunnel esophagogastric anastomosis technique to maximally reduce cervical anastomotic leakage and stricture rates after McKeown esophagectomy. The key features and innovations of cervical tunnel esophagogastric anastomosis are the right gastroepiploic artery as the center for the esophagogastric anastomosis to reduce ischemia, sufficient width of the anastomotic site for anastomosis without stricture, enfolding of the anastomotic site by the tunnel, and tension- and rotation-free anastomosis.