PROBLEM TO BE SOLVED: To provide compositions and methods for treating pathological conditions and diseases caused by the expression of a CD274/PD-L1 gene, e.g., a tumor such as ovarian cancer or melanoma, or an infectious disease such as viral hepatitis.SOLUTION: Described herein are double-stranded ribonucleic acid (dsRNA) compositions that cause the RNA-induced silencing complex (RISC)-mediated cleavage of RNA transcripts of the CD274/PD-L1 gene, and methods of inhibiting expression of CD274/PD-L using such dsRNA compositions.SELECTED DRAWING: Figure 1【課題】卵巣癌や黒色腫等の腫瘍、又はウイルス性肝炎等の感染症等のＣＤ２７４／ＰＤ－Ｌ１遺伝子の発現により引き起こされる病態及び疾患を治療するための組成物及び方法の提供。【解決手段】ＣＤ２７４／ＰＤ－Ｌ１遺伝子のＲＮＡ転写物のＲＮＡ誘発サイレンシング複合体（ＲＩＳＣ）の媒介による切断をもたらす二本鎖リボ核酸（ｄｓＲＮＡ）組成物、及びそのようなｄｓＲＮＡ組成物を使用してＣＤ２７４／ＰＤ－Ｌの発現を阻害する方法。【選択図】図１
