By transiently transfected into A549 cell using a luciferase reporter vector containing the 3′UTR fragment, we found that the miR-661 instead of control miRNAs conferred reduced luciferase activity of wild-type RB1 (Wt RB1-3′UTR) to NSCLC cells (P < 0.001) (Fig. 4b), while luciferase activity of mut RB1-3′UTR was not affected by miR-661 nor control miRNAs. This evidence concerns the gene RB1 and non-small cell lung carcinoma.