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A Millimeter Scale Flexural Testing System for Measuring the Mechanical Properties of Marine Sponge Spicules
Published on: October 11, 2017
New 4-methylidene sterols from the marine sponge Theonella swinhoei
Fan Yang1, Yan-Yun Li1, Jie Tang1
1Research Center for Marine Drugs, State Key Laboratory of Oncogenes and Related Genes, Department of Pharmacy, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200127, China.
Abstract:
A series of 4-methylidene sterols including three new compounds 1-3, were isolated from the marine sponge Theonella swinhoei. The structures of new compounds were determined on the basis of spectroscopic analyses. Compounds 3, 5, and 6 showed cytotoxicities against U937, MCF-7, and PC-9 cancer cells with IC50 in the range of 1.6-8.8 μM. The new compound 3 exhibited remarkable proapoptotic activity in breast cancer cells. Mechanically, 3 significantly triggered reactive oxygen species (ROS) accumulation resulting in apoptosis and DNA damage in breast cancer cells.
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