BACKGROUND Pleuromutilin is a natural tricyclic, derived from the fungus, 
Pleurotus mutilus. This study aimed to investigate the effects of pleuromutilin 
on migration and proliferation of A2780 and Caov-3 human ovarian carcinoma cells 
and the growth of A2780 tumor xenografts in mice and the molecular mechanisms 
involved. MATERIAL AND METHODS A2780 and Caov-3 human ovarian carcinoma cells 
were cultured with and without 40, 160, and 200 μM of pleuromutilin. The Edu 
fluorescence assay, the wound-healing assay, and Matrigel were used to measure 
A2780 and Caov-3 cell proliferation, migration, invasion, and adhesion in vitro, 
respectively. Western blot measured protein levels of FAK, p-FAK, MMP-2, and 
MMP-9. A2780 cells were injected subcutaneously into mice to determine the 
effects of pleuromutilin on the growth of tumor xenografts. RESULTS 
Pleuromutilin significantly reduced A2780 and Caov-3 cell proliferation at 48 h 
in a dose-dependent manner (P<0.05), and at 200 μM, pleuromutilin reduced cell 
proliferation by 21.43% and 23.65%, respectively. Treatment of A2780 cells with 
pleuromutilin significantly reduced cell migration, invasion, and adhesion and 
the expression of p-FAK, MMP-2, and MMP-9 compared with untreated controls. In 
the mouse tumor xenograft model, treatment with pleuromutilin significantly 
reduced tumor size compared with the untreated group and inhibited tumor 
metastasis to the intestine, spleen, and peritoneal cavity. CONCLUSIONS In A2780 
and Caov-3 human ovarian carcinoma cells, pleuromutilin inhibited cell 
proliferation, migration, invasion, and adhesion in a dose-dependent manner, and 
reduced tumor growth and metastases in a mouse A2780 cell tumor xenograft model.