The Anti-Proliferation Activity and Mechanism of Action of K(12)[V(18)O(42)(H(2)O)]∙6H(2)O on Breast Cancer Cell Lines

Polyoxometalates (POMs) are inorganic clusters that possess potential anti-bacterial, anti-viral, and anti-tumor activities. Herein, the in vitro anti-proliferation activities of K(12)[V(18)O(42)(H(2)O)]∙6H(2)O (V(18)) have been investigated on the MCF-7 and MDA-MB-231 cell lines. The results indicated that V(18) could inhibit the proliferation of MCF-7 (IC(50), 11.95 μM at 48 h) in a dose-dependent manner compared to the positive control, 5-fluorouracil (5-Fu, p < 0.05). The anti-proliferation activity of V(18) might be mediated by arrest of the MCF-7 cells in the G(2)/M phase and induction of apoptosis and necrosis. Moreover, V(18) can effectively quench the fluorescence of ctDNA. The binding mode between them may be groove or outside stacking binding. V(18) can also effectively quench the intrinsic fluorescence of bovine serum albumin (BSA) and human serum albumin (HSA) via static quenching, and changed the conformation of BSA and HSA.