CCND1 and neoplasm: Regulation of nuclear pre-mRNA domain containing 1B (RPRD1B), also named cell-cycle-related and expression-elevated protein in tumor (CREPT) or C20ORF77, is located on chromosome 20q11 and can bind to RNA polymerase on the cyclin D1 gene, resulting in the formation of a cyclin D1 ring structure, which can promote transcription (Lu et al., 2012; Wang et al., 2014).