Thiostrepton is a cyclic peptide antibiotic, densely packed with thiazoles and other structurally intriguing moieties. Thiostrepton exhibits antibiotic activity through blockade of ribosome turnover after an elongation step in protein synthesis by inhibiting both the dissociation of elongation factor G (EF-G) from the ribosome and the release of inorganic phosphate from EF-G following GTP hydrolysis. Thiostrepton is also described to show efficacy against cancer cell growth through downregulation of the forkhead box M1 (FOXM1) transcription factor, commonly overexpressed in many malignancies. Thiostrepton is an inhibitor of FOXM1 Thiostrepton is a cyclic peptide antibiotic, densely packed with thiazoles and other structurally intriguing moieties. Thiostrepton exhibits antibiotic activity through blockade of ribosome turnover after an elongation step in protein synthesis by inhibiting both the dissociation of elongation factor G (EF-G) from the ribosome and the release of inorganic phosphate from EF-G following GTP hydrolysis. Thiostrepton is also described to show efficacy against cancer cell growth through downregulation of the forkhead box M1 (FOXM1) transcription factor, commonly overexpressed in many malignancies. Thiostrepton is an inhibitor of FOXM1 A protein synthesis-inhibiting antibiotic