The sustained expansion of a tumor mass requires new blood vessel formation to provide rapidly proliferating tumor cells with an adequate supply of oxygen and nutrients. Hypoxia-inducible factor-1 (HIF-1) plays an essential role in tumor angiogenesis and growth by regulating the transcription of genes in response to hypoxic stress. This study was designed to investigate the effects of melatonin on tumor growth and angiogenesis, as well as the mechanism underlying the antitumor activities of melatonin. In this study, we show that the administration of melatonin inhibits tumor growth and blocks tumor angiogenesis in mice. Moreover, melatonin diminished the expression of the HIF-1α protein within the tumor mass during tumorigenesis. Our findings suggest that melatonin is a promising anti-angiogenic therapeutic agent targeting HIF-1α in cancer. Considering that HIF-1α is overexpressed in a majority of human cancers, melatonin could offer a potent therapeutic agent for cancer.

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A Z-scheme CeO2–AgI photocatalyst was successfully fabricated and its photocatalytic mechanism has been unraveled.

Facile preparation of metal–organic framework (MOF) derived earth-abundant nickel phosphide (Ni2P) by a simple, cost-effective procedure is described. Ni2P is recognized as a suitable replacement for expensive noble metal cocatalysts used for H2 production by water splitting. Ni2P nanoparticles were used to prepare a Ni2P/CdS composite with improved photocatalytic properties. Crystal structure and surface morphology studies showed that Ni-MOF spheres readily transform into Ni2P particles, and TEM images indicated the presence of Ni2P nanoparticles on CdS. The optical properties and charge carrier dynamics of the composite material exhibited better visible light absorption and improved suppression of charge carrier recombination. X-ray photoelectron spectra confirmed the presence of Ni2P on CdS. The synthesized materials were tested for photocatalytic hydrogen production with lactic acid as a scavenger under irradiation in a solar simulator. The rate of H2 production with Ni2P/CdS was 62 times greater than that with pure CdS. The superior activity of the composite material is attributed to the ability of Ni2P to separate the photoexcited charge carriers from CdS and provide good electrical conductivity. The optimized composite material also exhibited better photocatalytic activity than Pt cocatalyzed CdS. Based on the experimental results, a possible electron–hole transfer mechanism is proposed.

p-Coumaric acid, a hydroxy derivative of cinnamic acid, has been known to possess antioxidant and anticancer activities. Despite its potential contribution to chemopreventive effects, the mechanism by which p-coumaric acid exerts its antiangiogenic actions remains elusive. In this study, we revealed that p-coumaric acid inhibited the sprouting of endothelial cells in rat aortic rings and inhibited the tube formation and migration of endothelial cells. We observed that p-coumaric acid could downregulate mRNA expression levels of the key angiogenic factors vascular endothelial growth factor and basic fibroblast growth factor. Also, we demonstrated that p-coumaric acid inhibited both the AKT and ERK signaling pathways, which are known to be crucial for angiogenesis. Using a mouse model, we also showed that p-coumaric acid effectively suppressed tumor growth in vivo by lowering hemoglobin contents. Collectively, these findings indicate that p-coumaric acid possesses potent anticancer properties due to the inhibition of angiogenesis in vivo.

A facile, green protocol for the synthesis of self-assembled 3D porous ZnS-graphene aerogels (ZnS-GAs)using vitamin-C to obtain a 3D network of supramolecular hybrid nanostructured materials was developed.Structural, morphological, and optical measurements demonstrate that the ZnS-GAs nanostructures have good crystallinity, and the graphene nanosheets are densely decorated by ZnS nanostructures. The photocatalytic properties of ZnS-GAs were assessed based on photocatalytic degradation of methylene blue (MB) and Cr(VI) under simulated sunlight irradiation. Superior photocatalytic performance was achieved with the ZnS-GAs compared to bare ZnS. This enhancement is ascribed to efficient charge transfer from ZnS to the graphene sheets. Overall, the present work provides new insight into the green synthesis of 3D ZnS-GAs, and the developed composites are highly active photocatalysts with stable cycling that can be exploited in environmentally friendly applications.

This work demonstrates the facile synthesis of CdS/RGO-MoS2@CoP photocatalyst for H2 production via water splitting.

This work demonstrates a novel design strategy for MCTMPs with applications as sunlight-driven photocatalysts for hydrogen production through water splitting.