Described herein are compositions and methods for the inhibition of miR-21 activity. The compositions have certain nucleoside modification patterns that yield potent inhibitors of miR-21 activity. The compositions may be used to inhibit miR-21, and also to treat diseases associated with abnormal expression of miR-21, such as fibrosis and cancer.本文描述用於抑制miR-21活性之組合物及方法。該等組合物具有某些產生miR-21活性之有效抑制劑的核苷修飾型態。該等組合物可用於抑制miR-21,以及治療與miR-21之異常表現相關之疾病,諸如纖維化及癌症。