Ziziphus nummularia Attenuates the Malignant Phenotype of Human Pancreatic Cancer Cells: Role of ROS

Pancreatic cancer (PC) is the fourth leading cause of all cancer-related deaths. Despite major improvements in treating PC, low survival rate remains a major challenge, indicating the need for alternative approaches, including herbal medicine. Among medicinal plants is Ziziphus nummularia (family Rhamnaceae), which is a thorny shrub rich in bioactive molecules. Leaves of Ziziphus nummularia have been used to treat many pathological conditions, including cancer. However, their effects on human PC are still unknown. Here, we show that the treatment of human pancreatic ductal adenocarcinoma cells (Capan-2) with Ziziphus nummularia ethanolic extract (ZNE) (100–300 μg/mL) attenuated cell proliferation in a time- and concentration-dependent manner. Pretreatment with N-acetylcysteine, an ROS scavenger, attenuated the anti-proliferative effect of ZNE. In addition, ZNE significantly decreased the migratory and invasive capacity of Capan-2 with a concomitant downregulation of integrin α₂ and increased cell–cell aggregation. In addition, ZNE inhibited in ovo angiogenesis as well as reduced VEGF and nitric oxide levels. Furthermore, ZNE downregulated the ERK1/2 and NF-κB signaling pathways, which are known to drive tumorigenic and metastatic events. Taken together, our results suggest that ZNE can attenuate the malignant phenotype of Capan-2 by inhibiting hallmarks of PC. Our data also provide evidence for the potential anticancer effect of Ziziphus nummularia, which may represent a new resource of novel anticancer compounds, especially ones that can be utilized for the management of PC.     

Catalyst-Free Regio- and Diastereoselective Synthesis of Heterocyclic Nucleosides in the Eco-friendly Solvent 2-Methyltetrahydrofuran†

An efficient and practical synthesis of heterocyclic nucleosides is developed by a catalyst-free highly regioselective and diastereoselective [3+2] annulation of α-purine-substituted acrylates with nitrones. The reaction operates with excellent functional group tolerance, very mild reaction conditions, and with the green, sustainable, and eco-friendly 2-methyltetrahydrofuran (2-MeTHF) as solvent. Compared with other reactions of electron-deficient olefin dipolarophiles with nitrones, different regioselective cycloaddition products were observed in this work. This 1,3-dipolar cycloaddition reaction gives a series of isoxazolidinyl nucleosides in good to excellent yields with promising applications in biochemistry and medicinal chemistry.