RBL2 and neoplasm: Several other down-regulated genes such as Hes6 (inhibits cell proliferation), Rbl2 (tumour suppressor and inhibitor of E2F target genes) and Id1 (a bHLH transcription factor that regulates cell proliferation by supressing p21 or Cdkn1a, a CDKs inhibitor) were also observed as the putative targets of rno-miR-503, -214 and -146b and -503.