Format

Send to

Choose Destination
Cytokine. 2009 Dec;48(3):203-11. doi: 10.1016/j.cyto.2009.07.006. Epub 2009 Aug 7.

Expression patterns of leptin receptor (OB-R) isoforms and direct in vitro effects of recombinant leptin on OB-R, leptin expression and cytokine secretion by human hematopoietic malignant cells.

Author information

1
Division of Hematology, Department of Internal Medicine, Medical School, University of Patras, Patras, Greece. mouzaki@med.upatras.gr

Abstract

Several studies have implicated leptin in the pathophysiology of neoplasias. We investigated the direct effect of leptin on malignant hematopoietic tissue that included: primary acute myeloid leukemia (AML) cells, leukemic cell lines and bone marrow biopsies from multiple myeloma (MM) patients. PBMC, T-cells, B-cells and monocytes from healthy subjects served as controls. We defined the patterns of OB-R isoform expression in AML cells and leukemic cell lines in comparison to control cells by RT-PCR. rLeptin upregulated the expression of OB-R and endogenous leptin in AML blasts and certain cell lines but not in control cells. Cytometric Bead Array analysis of pro- and anti-inflammatory cytokines showed that rleptin upregulates IL-6 secretion by AML cells, various cytokines by the leukemic cell lines tested and IL-10 secretion by control PBMC, contributed by monocytes. Western immunoblotting revealed that the effect of rleptin was independent of JAK-2/phospho-JAK-2 protein levels. Finally, MM biopsies stained positive for leptin and, to a lesser extend, OB-R. Immunoreactivity was confined mostly to the nucleus of the myeloma cells. Normal myelocytes, promyelocytes and megakaryocytes stained weakly positive, and erythroid cells were constantly negative. We propose that the leptin/OB-R system is strongly and directly involved in supporting the growth of hematopoietic malignancies.

PMID:
19665393
DOI:
10.1016/j.cyto.2009.07.006
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center