Identification of Mithramycin Analogues with Improved Targeting of the EWS-FLI1 Transcription Factor.

Purpose: The goal of this study was to identify second-generation mithramycin analogues that better target the EWS-FLI1 transcription factor for Ewing sarcoma. We previously established mithramycin as an EWS-FLI1 inhibitor, but the compound's toxicity prevented its use at effective concentrations in patients.

Experimental Design: We screened a panel of mithralogs to establish their ability to inhibit EWS-FLI1 in Ewing sarcoma.