Effective inhibitory activity against MCF-7, A549 and HepG2 cancer cells by a phosphomolybdate based hybrid solid.

A novel Strandberg type polyoxomolybdate based organic–inorganic hybrid solid, [{4,4′-H2bpy}{4,4′-Hbpy}2{H2P2Mo5O23}]·5H2O (1) has been synthesized and structurally characterized by the single crystal X-ray diffraction technique. The structure consists of a discrete type phosphomolybdate cluster, [H2P2Mo5O23]4−, connected with three protonated 4,4′-bipyridine molecules by strong hydrogen bonding interactions. The In vitro anti-tumoral activity of compound (1) was tested against human breast cancer (MCF-7), human lung cancer (A549) and human liver cancer (HepG2) cells. The Strandberg type cluster was used against the MCF-7 and A549 cancer cells for the first time hitherto. It shows considerable inhibitory effect with IC50 values of 33.79 μmol L−1, 25.17 μmol L−1, and 32.11 μmol L−1 against HepG2, A549 and MCF-7 respectively. The anti-tumoral activity of 1 was also found to be comparable with that of a routinely used chemotherapeutic agent, methotrexate (MTX), with an IC50 value of 42.03 μmol L−1 for HepG2, 26.93 μmol L−1 for A549 and 49.79 μmol L−1 for MCF-7. The anti-proliferation activity is mediated by the arrest of the A549 and HepG2 cells in the S phase and MCF-7 in the G2/M phase of the cell cycle as suggested by flow cytometry. Results suggest that apoptosis and necrosis pathways ultimately lead to the death of the cancer cells.