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Background: Acquired resistance and adverse effects are some of the challenges faced by thousands of Luminal A breast cancer patients under tamoxifen (TMX) treatment. Some authors associate the overexpression of HOXB7 with TMX resistance in this molecular subtype, and the knockdown of this gene could be an effective strategy to regain TMX sensitivity. Therefore, we used calcium phosphate hybrid nanoparticles (HNP) for the delivery of short interfering RNA molecule (siRNA) complementary to the HOXB7 gene and evaluated the RNA interference (RNAi) effects associated with TMX treatment in breast cancer in vivo. Methods: HNP were prepared by the self-assembly of a methoxy-poly (ethylene glycol)-block-poly (L-glutamic acid) copolymer (PEG-pGlu) and the coprecipitation of CaPO4 to incorporate siRNA. The in vitro cell viability and migration were evaluated prior to in vivo experiments. Further, animals bearing early-stage and advanced Luminal A breast cancer were treated with HNP-siHOXB7, HNP-siHOXB7 + TMX, and TMX. Antitumoral activity and gene expression were evaluated following histopathological, hematological, and biochemical analysis. Results: The HNP were efficient in delivering the siRNA in vitro and in vivo, whilst HOXB7 silencing associated with TMX administration promoted controlled tumor growth, as well as a higher survival rate and reduction in immuno- and hepatotoxicity. Conclusions: Therefore, our findings suggest that HOXB7 can be an interesting molecular target for Luminal A breast cancer, especially associated with hormone therapy, aiming for adverse effect mitigation and higher therapeutic efficacy. [ABSTRACT FROM AUTHOR]

The Cu‐glutathione (GSH) redox system, essential in biology, is designed here as a supramacromolecular assembly in which the tetrahedral 18e Cu(I) center loses a thiol ligand upon adsorption onto ZIF‐8, as shown by EXAFS and DFT calculation, to generate a very robust 16e planar trigonal single‐atom Cu(I) catalyst. Synergy between Cu(I) and ZIF‐8, revealed by catalytic experiments and DFT calculation, affords CO2 conversion into high‐value‐added chemicals with a wide scope of substrates by reaction with terminal alkynes or propargyl amines in excellent yields under mild conditions and reuse at least 10 times without significant decrease in catalytic efficiency. [ABSTRACT FROM AUTHOR]

The generation of H2 from materials with a high content of H atoms is attractive for both sustainable energy and convenient hydrogenation. We report that the novel synthesized AuPd@ZIF-8-alloyed nanoparticles (ZIF = zeolitic imidazolate framework) in which the AuPd nanoparticles (NPs) have a size of 2.43 nm and are shown by Brunauer-Emmett-Teller (BET) surface to be encapsulated into ZIF-8. The AuPd and ZIF-8 nanoparticle is an excellent nanocatalyst for the evolution of H2 in the methanolysis reaction of aminoborane (AB) under visible light irradiation. Visible-light-induced acceleration is due to the Au plasmonic excitation provoking hot electron transfer from Au to Pd-substrate ensemble, whereas the reactions catalyzed by monometallic Au@ZIF-8 or Pd@ZIF-8 undergo only few minutes or no acceleration (respectively) under visible light irradiation. Three mol H2 per mol AB are produced in 6 min at 25 °C (TOF: 86.8 mol H2 molatom-1 min-1) with AuPd@ZIF-8 under visible light compared with incomplete H2 formation in 30 min in the dark. A comparison of various heterogeneous supports shows that the ZIF-8 encapsulation of the nanoalloy is by far the best support for this reaction. The large primary kinetic isotope effect (KIE) kH/kD = 3.4 with visible-light irradiation, the high turnover frequency (TOF) under light illumination (3.7 times higher than in the dark), and density functional theory (DFT) calculations confirm the mechanism and illustrate the more difficult O-H oxidative addition on Pd in methanol than in water in this process. This is due to the weaker acidity of methanol compared to that of water. Coupling labeling and tandem reactions with styrene hydrogenation showed that one H atom of H2 formed is provided by AB, while the other one is from methanol. The cleanness of the H2 generated and the recyclability of the NH4B(OMe)4 product render AB methanolysis attractive for lowtemperature H2 production devices and tandem reactions. [ABSTRACT FROM AUTHOR]

Hydrogen (H 2 ) generation and storage are actively investigated to provide a green source of energy, and formic acid (HCOOH), a major product obtained from the biomass, is regarded as a productive source of H 2 . Therefore, improvements in heterogeneous catalysts are called for. Here, a novel type of catalyst support is proposed involving simple addition of the mixture of metal ion precursors to core-shell ZIF-8@ZIF-67, followed by reduction with NaBH 4 , with performances surpassing those obtained using nanocatalysts in ZIF-8 or ZIF-67. The nanocatalysts Pd x Ag were optimized with ZIF-8@Pd 2 Ag 1 @ZIF-67 under visible-light illumination for selective HCOOH dehydrogenation involving a turnover frequency value of 430 h -1 under light irradiation at 353 K. These results also reveal the crucial roles of the Pd sites electronically promoted in the presence of visible light by the Ag plasmon resonance and the advantageous core-shell MOF structure. In order to examine the potential of extending this catalyst improvement principle to other catalytic reactions, 4-nitrophenol reduction, a benchmarking model of catalytic reaction, was tested, and the results also confirmed the superiority of the performance of ZIF-8@Pd 2 Ag 1 @ZIF-67 over Pd 2 Ag 1 @ZIF-8 and Pd 2 Ag 1 @ZIF-67, confirming the interest in the novel catalyst design.