The present invention includes compositions and methods of making and using an imaging label comprising an expression vector comprising a promoter and a nucleic acid insert operably linked to the promoter, wherein the insert encodes one or more short hairpin RNAs (shRNA) capable of inhibiting an expression of a target gene sequence that is a EWS-FLI1 fusion gene, a EWSR1-ERG fusion gene, or both in Ewing’s sarcoma via RNA interference wherein the one or more shRNA comprise a bifunctional RNA molecule that activates a cleavage-dependent and a cleavage-independent RNA-induced silencing complex for reducing the expression level of the target gene.本發明包括製造及使用包括表現載體之成像標記之組合物及方法,該表現載體包含啟動子及以操作方式連接至該啟動子之核酸插入物,其中該插入物編碼一或多種能夠經由RNA干擾法抑制靶基因序列(其係EWS-FLI1融合基因、EWSR1-ERG融合基因或此二者)在依汶氏(Ewings)肉瘤中之表現之短髮夾RNA(shRNA);其中該一或多種shRNA包括活化裂解依賴型及非裂解依賴型RNA誘導之沉默複合物,以減少該靶基因表現量之雙功能RNA分子。
