Increased number of mesenchymal stem cell-like cells in peripheral blood of patients with bone sarcomas.
OBJECTIVE
The number of peripheral blood mesenchymal stem cells (PBMSCs) may increase under pathological conditions. We sought to compare the number of MSC-like cells in the peripheral blood of patients with bone sarcomas with healthy controls and to analyze related cytokines in the peripheral blood plasma.


METHODS
Peripheral blood mononuclear cells (PBMNs) of patients with bone sarcomas and control subjects were isolated for culture and analyzed by flow cytometry for MSC phenotype. Cytokines in the plasma obtained after cell separation were analyzed using enzyme-linked immunosorbent assay (ELISA). Annexin-V and beta-galactosidase staining were used to investigate whether the cells died from apoptosis or senescence.


RESULTS
Flow cytometric analysis demonstrated an >9-fold increase in the number of cells with MSC-like phenotypes (CD34(-), CD45(-), CD105(+)) in patients with bone sarcomas compared with control subjects (p<0.05). ELISA results showed that concentrations of hepatocyte growth factor (HGF) and vascular endothelial growth factor (VEGF) in patients with bone sarcomas were statistically higher than those in the control subjects (p<0.05), whereas there was no significant difference in plasma concentrations of leptin and stromal cell-derived factor 1 between the two groups. A significant, positive correlation between the percentages of PBMSC-like cells and concentrations of HGF in all samples (R=0.618; p=0.011). Annexin-V staining of MSC-like cells was positive, whereas beta-galactosidase staining was negative.


CONCLUSIONS
Peripheral blood of patients with bone sarcomas has more cells with MSC phenotypes than blood of healthy persons. The increased number is accompanied by increased HGF and VEGF in the plasma.
Department of Orthopedic Surgery, Shanghai Ninth People's Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, PR China.
Zhen-Yu
ZY
Bian
Gang
G
Li
Yao-Kai
YK
Gan
Yong-Qiang
YQ
Hao
Wen-Ting
WT
Xu
Ting-Ting
TT
Tang
D000293:Adolescent; D000328:Adult; D017304:Annexin A5 / Q000378:metabolism; D017209:Apoptosis / Q000502:physiology; D001859:Bone Neoplasms / Q000097:blood* / Q000473:pathology*; D002452:Cell Count; D054377:Chemokine CXCL12 / Q000097:blood; D005260:Female; D017228:Hepatocyte Growth Factor / Q000097:blood; D006801:Humans; D020738:Leptin / Q000097:blood; D008297:Male; D059630:Mesenchymal Stem Cells / Q000473:pathology*; D008875:Middle Aged; D012509:Sarcoma / Q000097:blood* / Q000473:pathology*; D042461:Vascular Endothelial Growth Factor A / Q000097:blood; D055815:Young Adult; D001616:beta-Galactosidase / Q000378:metabolism
D017304:Annexin A5; D054377:Chemokine CXCL12; C066855:HGF protein, human; D020738:Leptin; C467484:VEGFA protein, human; D042461:Vascular Endothelial Growth Factor A; D017228:Hepatocyte Growth Factor; D001616:beta-Galactosidase