To extend the potential involvement of MUC1-C in driving SCLC cell-cycle progression, we focused on H69 and DMS53 cells and found that MUC1-C induces expression of CCNA2 (cyclin A2) and CDK1, which in concert regulate entry into mitosis (Supplementary Fig. S3C; ref. 30). This evidence concerns the gene CDK1 and small cell lung carcinoma.