Antitumor efficacy of lidamycin against human multiple myeloma RPMI 8226 cells and the xenograft in nonobese diabetic/severe combined immunodeficiency mice

Aims: The aim of this study is to explore the antitumor efficacy of lidamycin (LDM) against human multiple myelomas (MM). Materials and Methods: Human MM RPMI 8226 cells and the xenograft model in nonobese diabetic/severe combined immunodeficient (NOD/SCID) mice were used to examine the antitumor activity of LDM. Results: Notably, LDM markedly suppressed the growth of human MM RPMI 8226 xenograft in NOD/SCID mice. In vitro , there was a significant reduction in cell proliferation after treatment with LDM. The overall growth inhibition correlated with the increase of apoptotic cells. The apoptosis-related proteins including caspase-3, 7, and 9 were activated, and poly adenosine diphosphate-ribose polymerase was cleaved. Further investigation revealed that cellular Bcl-2 and survivin decreased, whereas the level of Bax increased in the LDM-treated cells. Conclusions: LDM is highly effective against the growth of MM xenograft in NOD/SCID mice. The potent apoptosis.inducing effect of LDM may be mediated through caspase. and mitochondria.dependent pathway.