title: Ubiquitous expression of MAKORIN-2 in normal and malignant hematopoietic cells and its growth promoting activity.
abstract: Makorin-2 (MKRN2) is a highly conserved protein and yet its functions are largely unknown. We investigated the expression levels of MKRN2 and RAF1 in normal and malignant hematopoietic cells, and leukemia cell lines. We also attempted to delineate the role of MKRN2 in umbilical cord blood CD34+ stem/progenitor cells and K562 cell line by over-expression and inhibition of MKRN2 through lentivirus transduction and shRNA nucleofection, respectively. Our results provided the first evidence on the ubiquitous expression of MKRN2 in normal hematopoietic cells, embryonic stem cell lines, primary leukemia and leukemic cell lines of myeloid, lymphoid, erythroid and megakaryocytic lineages. The expression levels of MKRN2 were generally higher in primary leukemia samples compared with those in age-matched normal BM cells. In all leukemia subtypes, there was no significant correlation between expression levels of MKRN2 and RAF1. sh-MKRN2-silenced CD34+ cells had a significantly lower proliferation capacity and decreased levels of the early stem/progenitor subpopulation (CFU-GEMM) compared with control cultures. Over-expression of MKRN2 in K562 cells increased cell proliferation. Our results indicated possible roles of MKRN2 in normal and malignant hematopoiesis.
authors.affiliation: Department of Paediatrics, The Chinese University of Hong Kong, Hong Kong.
authors.forename: King Yiu
authors.initials: KY
authors.lastname: Lee
authors.affiliation: Department of Paediatrics, The Chinese University of Hong Kong, Hong Kong.
authors.forename: Kathy Yuen Yee
authors.initials: KY
authors.lastname: Chan
authors.affiliation: Department of Anatomical and Cellular Pathology, The Chinese University of Hong Kong, Hong Kong.
authors.forename: Kam Sze
authors.initials: KS
authors.lastname: Tsang
authors.affiliation: Centre for Emerging Infectious Diseases, Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Hong Kong.
authors.forename: Yang Chao
authors.initials: YC
authors.lastname: Chen
authors.affiliation: Centre for Emerging Infectious Diseases, Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Hong Kong.
authors.forename: Hsiang-fu
authors.initials: HF
authors.lastname: Kung
authors.affiliation: Department of Paediatrics, The Chinese University of Hong Kong, Hong Kong.
authors.forename: Pak Cheung
authors.initials: PC
authors.lastname: Ng
authors.affiliation: Department of Paediatrics, The Chinese University of Hong Kong, Hong Kong.
authors.forename: Chi Kong
authors.initials: CK
authors.lastname: Li
authors.affiliation: Department of Paediatrics, The Chinese University of Hong Kong, Hong Kong.
authors.forename: Kam Tong
authors.initials: KT
authors.lastname: Leung
authors.affiliation: Department of Paediatrics, The Chinese University of Hong Kong, Hong Kong.
authors.forename: Karen
authors.initials: K
authors.lastname: Li
mesh_terms: D045744:Cell Line, Tumor; D002478:Cells, Cultured; D053595:Embryonic Stem Cells / Q000378:metabolism; D015870:Gene Expression; D020868:Gene Silencing; D006410:Hematopoiesis / Q000235:genetics*; D006412:Hematopoietic Stem Cells / Q000378:metabolism; D006801:Humans; D020014:K562 Cells; D007938:Leukemia / Q000235:genetics*; D007963:Leukocytes, Mononuclear / Q000378:metabolism*; D019908:Proto-Oncogene Proteins c-raf / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics; D034741:RNA, Small Interfering / Q000235:genetics; D012261:Ribonucleoproteins / Q000235:genetics* / Q000378:metabolism
chemical_list: C512670:MKRN2 protein, human; D012333:RNA, Messenger; D034741:RNA, Small Interfering; D012261:Ribonucleoproteins; D019908:Proto-Oncogene Proteins c-raf