title: The role of microRNAs in normal and malignant hematopoiesis.
abstract: MicroRNAs are small non-coding RNAs that act at the post-transcriptional level, regulating protein expression by repressing translation or destabilizing mRNA target. Because of their discovery, microRNAs have been associated with almost every normal cell function, including proliferation, differentiation and apoptosis. Several lines of evidence suggest that they have an important role in normal hematopoiesis as exemplified by the role of mir-155 and mir-150 in the differentiation of B and T lymphocytes, the suppressive role of mir-221 and mir-222 in erythroid differentiation, the inhibitory effect of mir-181 on hematopoietic differentiation and the induction of myeloid differentiation by mir-223. Moreover, they play a role both as oncogenes, probably by a variety of mechanisms, namely through elimination of tumor suppressor proteins, or as tumor suppressor genes by targeting oncogenic mRNAs. Their aberrant expression has been associated with solid tumors and hematopoietic malignancies as suggested by the frequent deletion of mir-15a and mir-16-1 in chronic lymphocytic leukemia, the increased levels of mir-155 in diffuse large B-cell lymphomas and the increased levels of mir-181 in acute myeloid leukemia M1 and M2. The purpose of this review is to summarize current knowledge on the role of microRNAs in normal hematopoiesis and hematopoietic malignancies and, moreover, to highlight their role as potential therapeutic tools.
authors.affiliation: Second Department of Internal Medicine, University of Athens, University General Hospital "Attikon", Haidari, Greece.
authors.forename: Diamantina
authors.initials: D
authors.lastname: Vasilatou
authors.forename: Sotirios
authors.initials: S
authors.lastname: Papageorgiou
authors.forename: Vassiliki
authors.initials: V
authors.lastname: Pappa
authors.forename: Efstathios
authors.initials: E
authors.lastname: Papageorgiou
authors.forename: John
authors.initials: J
authors.lastname: Dervenoulas
mesh_terms: D000818:Animals; D002471:Cell Transformation, Neoplastic / Q000235:genetics; D015536:Down-Regulation; D015672:Erythroid Precursor Cells / Q000166:cytology; D005786:Gene Expression Regulation / Q000235:genetics*; D015972:Gene Expression Regulation, Neoplastic / Q000235:genetics; D016147:Genes, Tumor Suppressor; D019337:Hematologic Neoplasms / Q000235:genetics* / Q000473:pathology; D006410:Hematopoiesis / Q000235:genetics*; D006801:Humans; D007448:Invertebrates / Q000235:genetics; D008214:Lymphocytes / Q000166:cytology; D051379:Mice; D035683:MicroRNAs / Q000037:antagonists & inhibitors / Q000235:genetics / Q000502:physiology*; D022423:Myeloid Cells / Q000166:cytology; D009363:Neoplasm Proteins / Q000096:biosynthesis / Q000235:genetics; D009857:Oncogenes; D012334:RNA, Neoplasm / Q000037:antagonists & inhibitors / Q000235:genetics
chemical_list: D035683:MicroRNAs; D009363:Neoplasm Proteins; D012334:RNA, Neoplasm