For example, conserved helix-loop-helix ubiquitous kinase (CHUK), which is also known as IKK1, a protein kinase that plays an important role in pancreatic cancer and prostate cancer by regulating the NF-kB transcription factor, has two indels that may disrupt targeting by miR-223; RB1 contains one indel in target site of miR-335; STAT3 contains two indels in target sites of miR-9 and miR-125b; and FOXO1 and EFGR have indels in target sites of miR-9 and miR-7 respectively. Here, RB1 is linked to prostate cancer.