Antitumor activity of polyoxomolybdate, [NH3Pr1]6[Mo7O24]•3H2O, against, human gastric cancer model

Polyoxometalates are negatively charged inorganic compounds which contain metal ions such as tungsten, molybdenum, vanadium etc. and which make clusters with the surrounding oxygen atoms. [NH3Pri](6)[Mo7O24]center dot 3H(2)O (PM-8) was found to be a significant antitumor polyoxomolybdates. It had already been reported that the PM-8 suppressed the growth of Co-4 human colon cancer, MX-I human breast cancer and OAT human lung cancer xenografted in nude mice. However, the mechanism of the antitumor activity has not been clarified. In this study, the antitumor activity of one of the metal oxide clusters (polyoxometalates), hexabis(isopropylammonium) heptamolybdate trihydrate, [NH3Pri](6)[Mo7O24]center dot 3H(2)O (PM-8) were shown in an MTS assay. DNA ladder formation and detection of apoptotic bodies in nuclei were revealed that antitumor activity of PM-8 in MKN45 cells was due to apoptosis. It is concluded that the observation of significant tumor growth suppression of PM-8 in MKN45-bearing mice results from the induction of apoptosis. PM-8 shows promise as a novel anti-cancer agent. (c) 2006 Elsevier SAS. All rights reserved.