CD26/dipeptidyl peptidase IV regulates prostate cancer metastasis by degrading SDF-1/CXCL12.
Stromal derived factor-1 (SDF-1 or CXCL12) expressed by osteoblasts and endothelial cells, and its receptors CXCR4 and CXCR7/RDC1 are key molecular determinants in prostate cancer (PCa) metastasis. What drives PCa cells into the extravascular marrow space(s) once they make contact with the blood vessel endothelium, however remains unclear. Here, we evaluated whether degradation of CXCL12 facilitates PCa cell entry into the marrow cavity by locally lowering CXCL12 levels intravascularly. To explore this possibility, co-cultured conditioned media from PCa cells and endothelial cells were evaluated for their ability to degrade biotinylated CXCL12 (bCXCL12). Co-culture of PCa cells/endothelial cells resulted in greater digestion of CXCL12 than was achieved by either cell type alone, and this activity regulated invasion in vitro. The ability to degrade CXCL12 was not however observed in PCa and osteoblasts co-cultures. Fractionation and inhibitor studies suggested that the activity was CD26/dipeptidyl peptidase IV (DPPIV) and possibly other cysteine/serine proteases. By inhibiting CD26/DPPIV, invasion and metastasis of PCa cell lines were enhanced in in vitro and in vivo metastasis assays. Together, these data suggest that the degradation of CXCL12 by CD26/DPPIV may be involved in the metastatic cascades of PCa, and suggests that inhibition of CD26/DPPIV may be a trigger of PCa metastasis.
Department of Periodontics and Oral Medicine, University of Michigan School of Dentistry, Room 3307, 1011 North University Avenue, Ann Arbor, MI 48109-1078, USA.
Yan-Xi
YX
Sun
Elisabeth A
EA
Pedersen
Yusuke
Y
Shiozawa
Aaron M
AM
Havens
Younghun
Y
Jung
Jingcheng
J
Wang
Kenneth J
KJ
Pienta
Russell S
RS
Taichman
D000818:Animals; D054377:Chemokine CXCL12 / Q000032:analysis / Q000378:metabolism*; D018920:Coculture Techniques; D003546:Cysteine Endopeptidases / Q000502:physiology; D018819:Dipeptidyl Peptidase 4 / Q000502:physiology*; D006801:Humans; D008297:Male; D051379:Mice; D016513:Mice, SCID; D009362:Neoplasm Metastasis; D011471:Prostatic Neoplasms / Q000473:pathology*; D012697:Serine Endopeptidases / Q000502:physiology
C515255:CXCL12 protein, human; D054377:Chemokine CXCL12; D018819:Dipeptidyl Peptidase 4; D012697:Serine Endopeptidases; D003546:Cysteine Endopeptidases