ADAR1 exhibits oncogenic effects in an RNA-editing-dependent manner. (A) Cell growth curve of U266 (top) and KMS12BM (bottom) after ADAR1 knockdown and overexpression during a 5-day course. (B) Percentage cell population in different cell cycle phases of U266 and KMS12BM after ADAR1 knockdown and overexpression. (C) Representative images and the quantification of colonies formed in U266 (top) and KMS12BM (bottom) grown in methylcellulose-based media during a 7-14-day period. Each experiment was performed in triplicate, and data were expressed as the mean ± sd of triplicate wells. (D) Quantification of tumor volume and image of tumors formed in mice engrafted with U266-shCtrl and U266-shADAR1 at both the left and the right flanks, respectively (n = 5), and in mouse groups engrafted with OCIMY5-EV, OCIMY5-ADAR1-WT, or OCIMY5-ADAR1-Mutant (n = 15). (E) Western blot showing ADAR1 protein expression deriving from the harvested and lysed mouse tumors. **P < .05; ***P < .001.