title: Human umbilical cord blood-derived mesenchymal stem cells (hUCB-MSC) inhibit the proliferation of K562 (human erythromyeloblastoid leukaemic cell line).
abstract: hUCB-MSC (human umbilical cord blood-derived mesenchymal stem cells) offer an attractive alternative to bone marrow-derived MSC for cell-based therapy by being less invasive a source of biological material. We have evaluated the effect of hUCB-MSC on the proliferation of K562 (an erythromyeloblastoid cell line) and the cytokine secretion pattern of hUCB-MSC. Co-culturing of hUCB-MSC and K562 resulted in inhibition of proliferation of K562 in a dose-dependent manner. However, the anti-proliferative effect was reduced in transwells, suggesting the importance of direct cell-to-cell contact. hUCB-MSC inhibited proliferation of K562, arresting them in the G0 /G1 phase. NO (nitric oxide) was not involved in the hUCB-MSC-mediated tumour suppression. The presence of IL-6 (interleukin 6) and IL-8 were obvious in the hUCB-MSC conditioned media, but no significant increase was found in 29 other cytokines. Th1 cytokines, IFNα (interferon α), Th2 cytokine IL-4 and Th17 cytokine, IL-17 were not secreted by hUCB-MSC. There was an increase in the number of hUCB-MSC expressing the latent membrane-bound form of TGFβ1 co-cultured with K562. The anti-proliferative effect of hUCB-MSC was due to arrest of the growth of K562 in the G0 /G1 phase. The mechanisms underlying increased IL-6 and IL-8 secretion and LAP (latency-associated peptide; TGFβ1) by hUCB-MSC remains unknown.
authors.affiliation: Immunology Laboratory, Department of Pathology, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia.
authors.forename: Malini
authors.initials: M
authors.lastname: Fonseka
authors.forename: Rajesh
authors.initials: R
authors.lastname: Ramasamy
authors.forename: Boon Chong
authors.initials: BC
authors.lastname: Tan
authors.forename: Heng Fong
authors.initials: HF
authors.lastname: Seow
mesh_terms: D002450:Cell Communication; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D064987:Cell- and Tissue-Based Therapy; D018920:Coculture Techniques; D003260:Contact Inhibition / Q000502:physiology*; D059585:G1 Phase Cell Cycle Checkpoints; D006801:Humans; D015850:Interleukin-6 / Q000378:metabolism*; D016209:Interleukin-8 / Q000378:metabolism*; D004915:Leukemia, Erythroblastic, Acute / Q000378:metabolism*; D059630:Mesenchymal Stem Cells / Q000378:metabolism*; D009569:Nitric Oxide; D053773:Transforming Growth Factor beta1 / Q000378:metabolism; D014470:Umbilical Cord / Q000166:cytology
chemical_list: D015850:Interleukin-6; D016209:Interleukin-8; C508960:TGFB1 protein, human; D053773:Transforming Growth Factor beta1; D009569:Nitric Oxide