The present invention includes compositions and methods of making and using 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 SRC-3 gene 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 SRC-3.本發明包含製造且利用表現載體之組合物及方法,該表現載體包括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干擾抑制SRC-3基因表現之短髮夾RNA(shRNA),其中該一或多種shRNA包括雙功能RNA分子,其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SRC-3表現量。