Biflavonoids from Selaginella doederleinii as Potential Antitumor Agents for Intervention of Non-Small Cell Lung Cancer
Fenghua Kang, Sha Zhang, Dekun Chen, Jianbing Tan, Min Kuang, Jinlin Zhang, Guangyuan Zeng, Kang Xu, Zhen‐Xing Zou, Guishan Tan
Abstract
Four new biflavonoids (1–4) were isolated from Selaginella doederleinii together with a known biflavonoid derivative (5). Their structures contained a rare linker of individual flavones to each other by direct C-3-O-C-4′′′ bonds, and were elucidated by extensive spectroscopic data, including HRESIMS, NMR and ECD data. All isolates significantly inhibited the proliferation of NSCLC cells (IC50 = 2.3–8.4 μM) with low toxicity to non-cancer MRC-5 cells, superior to the clinically used drug DDP. Furthermore, the most active compound 3 suppressed XIAP and survivin expression, promoted upregulation of caspase-3/cleaved-caspase-3, as well as induced cell apoptosis and cycle arrest in A549 cells. Together, our findings suggest that 3 may be worth studying further for intervention of NSCLC.