Possible contribution of aminopeptidase N (APN/CD13) to invasive potential enhanced by interleukin-6 and soluble interleukin-6 receptor in human osteosarcoma cell lines.
This study aimed at clarifying the role of Aminopeptidase N (APN), a Zn2+-dependent ectopeptidase localized on the cell surface of human osteosarcoma cell lines treated with proinflammatory cytokines. We investigated the proinflammatory cytokines interleukin-1 beta (IL-1beta), IL-6 and tumor necrosis factor alpha (TNF-alpha) as well as the anti-inflammatory cytokine transforming growth factor beta (TGF-beta) for their influence on APN regulation. Soluble IL-6 receptor (sIL-6R) was always used together with IL-6 to achieve a stable effect. In addition, the invasive potential of the osteosarcoma cell lines MG63 and HOS was examined. Competitive RT-PCR and Ala-pNA activity assays revealed that IL-6 and sIL-6R significantly increased the mRNA expression and activity of APN in both osteosarcoma cell lines. Although IL-1beta significantly stimulated APN mRNA expression in both cell lines, it influenced the enzyme activity only in MG63. TNF-alpha and TGF-beta, however, had an effect neither on mRNA expression nor on the enzyme activity of APN in both cell lines. In the Matrigel invasion assay, IL-6 and sIL-6R significantly up-regulated the transmigration of these cell lines, whereas other cytokines did not. The up-regulated invasion was inhibited by bestatin, a specific inhibitor of APN. Cellular migration correlated highly with APN activity (r = 0.79, P < 0.002). These findings suggest that APN contributes to the invasive potential of human osteosarcomas enhanced by IL-6 and SIL-6R.
Kido
A
A
Department of Pathology, Otto-von-Guericke University Magdeburg, Germany. akirakid@naramed-u.ac.jp
Krueger
S
S
Haeckel
C
C
Roessner
A
A
D001859:Bone Neoplasms / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology*; D018826:CD13 Antigens / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D007375:Interleukin-1 / Q000494:pharmacology; D015850:Interleukin-6 / Q000737:chemistry / Q000494:pharmacology; D009361:Neoplasm Invasiveness; D012516:Osteosarcoma / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology*; D018123:Receptors, Interleukin / Q000737:chemistry; D019947:Receptors, Interleukin-6; D011993:Recombinant Fusion Proteins / Q000737:chemistry; D016212:Transforming Growth Factor beta / Q000494:pharmacology; D014407:Tumor Cells, Cultured; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
D007375:Interleukin-1; D015850:Interleukin-6; D018123:Receptors, Interleukin; D019947:Receptors, Interleukin-6; D011993:Recombinant Fusion Proteins; D016212:Transforming Growth Factor beta; D014409:Tumor Necrosis Factor-alpha; C104543:interleukin 6-interleukin 6 receptor fusion protein, recombinant; D018826:CD13 Antigens