MYC and cancer: The expression of miR-17-92 cluster is precisely regulated in malignant tumors by many transcriptional factors including MYC proto-oncogene, bHLH transcription factor (C-MYC), MYCN proto-oncogene, bHLH transcription factor (N-MYC), E2F transcription factor 1 (E2F1), and E2F transcription factor 3 (E2F3)3.