In this study, we evaluated the anti-cancer activity and potential molecular mechanism of 70% ethanol extracts of branches from Taxillus yadoriki parasitic to Neolitsea sericea (TN-NS-B) against human lung cancer cells, A549. TY-NS-B dose-dependently suppressed the growth of A549 cells. TY-NS-B decreased β-catenin protein level, but not mRNA level in A549 cells. The downregulation of β-catenin protein level by TY-NS-B was attenuated in the presence of MG132. Although TY-NS-B phosphorylated β-catenin protein, the inhibition of GSK3β by LiCl did not blocked the reduction of β-catenin by TY-NS-B. In addition, TY-NS-B decreased β-catenin protein in A549 cells transfected with Flag-tagged wild type β- catenin or Flag-tagged S33/S37/T41 mutant β-catenin construct. Our results suggested that TN-NS-B may downregulate β- catenin protein level independent on GSK3β-induced β-catenin phosphorylation. Based on these findings, TY-NS-B may be a potential candidate for the development of chemopreventive or therapeutic agents for human lung cancer.

Dendropanax morbifera Léveille (Araliaceae) is an endemic species growing in the south-western part of South Korea and has been used in folk medicine and health functional food. Several studies have indicated that extract of D. morbifera (DP) has cytotoxic activities on a number of human cancers, such as, breast cancer, lung cancer, hepatoma, and chorioepithelioma. Recently, polyacetylene and triterpene compounds have been isolated from the DP and showed to have anti-complement activity. β-Amyrin, α-amyrin, dendropanoxide, and β-sitosterol are isolated from DP. However, its biological activities in cancer have not yet been clearly elucidated. In this study, we evaluated the anti-cancer activity of isolated triterpenoids from the DP leaves by measuring the levels of cytotoxicity against MCF-7 human breast cancer and A549 human lung cancer cells. Six triterpenoids were isolated from the n-hexane fraction of DP leaves along with the known compounds. β-amyrin (1), α-amyrin (2), olean-12-en-3,24 β-diol (3), dendropanoxide (4), β-sitosterol (5), and stigmasterol (6). Compound 3 and 6 were isolated from DP for the first time. Cytotoxic activities of six compounds were evaluated against two human cancer cell lines by using the MTT in vitro assay. Among them, five compounds (1, 2, 4, 5, and 6) showed moderate cytotoxic activities toward the tested cell lines, and were safe to normal cells. Western blot analysis showed a decreased expression of anti-apoptotic protein Bcl-2 and increased levels of pro-apoptotic protein Bax in MCF-7 and A549 cells treated by β-amyrin and α-amyrin. Flow cytometry analysis confirmed that five compounds (1, 2, 4, 5, and 6) treatment increased populations of sub-G1 (apoptosis) phase. The results of the present study revealed that triterpenoids from DP have the potential for further development as anticancer agents.

This study investigated in vitro antioxidant, anti-inflammatory and cytotoxicity on human lung epithelial A549 cells of different solvent extracts from Jerusalem artichoke (Helianthus tuberosus L.) tuber. The EtOH extract contained amounts of phenolics (22.20 tannic acid equivalent ㎎/ɡ) and exhibited the highest antioxidant activity and anti-inflammatory activity. Several methods were employed for measure the antioxidant activity: 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity (IC50 = 206.79 ㎍/㎖), reducing power activity (21.26 ascorbic acid equivalent ㎎/ɡ) and total antioxidant activity (19.05 ascorbic acid equivalent ㎎/ɡ). Meantime, the EtOH extract inhibited the NO production completely with a concentration of 800 ㎍/㎖. Besides, the H2O extract exhibited more potent effect on human lung epithelial A549 cells. This study suggested that Jerusalem artichoke tuber had antioxidant, anti-inflammatory and cytotoxicity on human lung epithelial A549 cells.