Targeting the giant cell tumor stromal cell: functional characterization and a novel therapeutic strategy.
Giant cell tumor of bone (GCTB) is a benign, locally destructive neoplasm, with tumors comprised of mesenchymal fibroblast-like stromal cells; monocytic, mononuclear cells of myeloid lineage; and the characteristic osteoclast-like, multinucleated giant cells. Hampering the study of the complex interaction of its constituent cell types is the propensity of longstanding, repeatedly passaged cell cultures to undergo phenotypic alteration and loss of osteoclast-inducing capacities. In this study, we employed a novel, single-step technique to purify freshly harvested stromal cells using a CD14-negative selection column. Using 9 freshly harvested GCTB specimens and the purified stromal cell component, we performed analyses for markers of osteoblast lineage and analyzed the capacity of the stromal cells to undergo osteoblastic differentiation and induce osteoclastogenesis in co-cultures with monocytic cells. Successful purification of the CD14-negative stromal cells was confirmed via flow cytometric analysis and immunocytochemistry. Osteogenic media upregulated the expression of osteocalcin, suggesting an osteoblastic lineage of the GCTB stromal cells. The effects of the Wnt pathway agonist, SB415286, and recombinant human bone morphogenetic protein (BMP)-2 on osteoblastogenesis varied among samples. Notably, osteogenic media and SB415286 reversed the receptor activator of NF-κB ligand (RANKL)/osteoprotegerin (OPG) expression ratio resulting in diminished osteoclastogenic capacity. Recombinant human BMP2 had the opposite effect, resulting in enhanced and sustained support of osteoclastogenesis. Targeting the giant cell tumor stromal cell may be an effective adjunct to existing anti-resorptive strategies.
Department of Surgery, Spectrum Health Medical Group/Michigan State University College of Human Medicine, Grand Rapids, Michigan, United States of America. matt.steensma@vai.org
Matthew R
MR
Steensma
Wakenda K
WK
Tyler
Allison G
AG
Shaber
Steven R
SR
Goldring
F Patrick
FP
Ross
Bart O
BO
Williams
John H
JH
Healey
P Edward
PE
Purdue
D000293:Adolescent; D000328:Adult; D000627:Aminophenols / Q000494:pharmacology / Q000627:therapeutic use; D019485:Bone Morphogenetic Proteins / Q000378:metabolism; D002454:Cell Differentiation / Q000187:drug effects; D002469:Cell Separation; D003470:Culture Media / Q000494:pharmacology; D005260:Female; D018212:Giant Cell Tumor of Bone / Q000188:drug therapy / Q000473:pathology* / Q000628:therapy*; D006801:Humans; D008024:Ligands; D008297:Male; D008301:Maleimides / Q000494:pharmacology / Q000627:therapeutic use; D008875:Middle Aged; D010006:Osteoblasts / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D010010:Osteoclasts / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D010012:Osteogenesis / Q000187:drug effects; D053244:Osteoprotegerin / Q000378:metabolism; D016133:Polymerase Chain Reaction; D053245:RANK Ligand / Q000378:metabolism; D017154:Stromal Cells; D060449:Wnt Signaling Pathway / Q000187:drug effects; D055815:Young Adult
C417520:3-(3-chloro-4-hydroxyphenylamino)-4-(4-nitrophenyl)-1H-pyrrole-2,5-dione; D000627:Aminophenols; D019485:Bone Morphogenetic Proteins; D003470:Culture Media; D008024:Ligands; D008301:Maleimides; D053244:Osteoprotegerin; D053245:RANK Ligand