CDKN1A and hepatocellular carcinoma: Moreover, miR-221 targets are the E2F transcription factor 1 (E2F1), the phosphatase and tensin homolog (PTEN) and the cyclin-dependent kinase inhibitor 1 (CDKN1A), all belonging to critical cancer related pathways in HCC as well as other types of cancer including melanoma [212].