title: Alterations of circulating bone marrow-derived VEGFR-2+ progenitor cells in isolated limb perfusion with or without rhTNF-α.
abstract: BACKGROUND
  Circulating endothelial progenitor cells (cEPCs) as recruited to the angiogenic vascular system of malignant tumors have been proposed as a biomarker in malignancies. The effect of antitumor chemotherapy on cEPCs is not fully understood. We examined the level of cEPCs, vascular endothelial growth factor (VEGF), and angiopoietin-2 in the blood of sarcoma and melanoma patients before and after isolated limb perfusion (ILP) with or without recombinant human tumor necrosis factor-α (rhTNF-α).
  
  
  METHODS
  Twenty-two patients, 11 each with soft tissue sarcoma or recurrent melanoma of the limb, were recruited. ILP was performed with rhTNF-α/melphalan (TNF) or melphalan only (no TNF). Fifteen healthy volunteers served as control subjects. Blood was sampled before and up to 6 weeks after ILP. Peripheral blood mononuclear cells were isolated by density gradient centrifugation, and annexin V-negative cells were characterized as cEPCs by triple staining for CD133(+), CD34, and VEGFR-2(+).
  
  
  RESULTS
  Before treatment, cEPC numbers were significantly increased in sarcoma (0.179 ± 0.190 %) and melanoma patients (0.110 ± 0.073 %) versus healthy controls (0.025 ± 0.018 %; P < 0.01), but did not differ significantly between sarcoma and melanoma patients. cEPC decreased significantly after ILP in patients with no TNF compared to pretreatment values (P < 0.05) and were significantly lower at 4 h, 48 h, and 1 week compared to ILP with TNF (P < 0.05). Values 6 weeks after ILP were significantly lower than before ILP in both investigated groups (P < 0.01).
  
  
  CONCLUSIONS
  ILP with TNF results in activation of bone marrow-derived EPCs compared to ILP without TNF. Alteration of cEPCs and angiopoietin-2 by rhTNF-α might account for the cytotoxicity and hemorrhagic effects on tumor vessels during limb perfusion procedures.
authors.affiliation: Division of Surgical Oncology and Thoracic Surgery, Department of Surgery, Mannheim University Medical Center, Heidelberg University, Heidelberg, Germany. kai.nowak@umm.de
authors.forename: Kai
authors.initials: K
authors.lastname: Nowak
authors.forename: Nicole
authors.initials: N
authors.lastname: Jachol
authors.forename: Neysan
authors.initials: N
authors.lastname: Rafat
authors.forename: Elena
authors.initials: E
authors.lastname: Joas
authors.forename: Grietje Ch
authors.initials: GCh
authors.lastname: Beck
authors.forename: Peter
authors.initials: P
authors.lastname: Hohenberger
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D001853:Bone Marrow / Q000378:metabolism / Q000473:pathology*; D016022:Case-Control Studies; D002478:Cells, Cultured; D010478:Chemotherapy, Cancer, Regional Perfusion; D002945:Cisplatin / Q000008:administration & dosage; D003131:Combined Modality Therapy; D004730:Endothelium, Vascular / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D004797:Enzyme-Linked Immunosorbent Assay; D005121:Extremities; D005260:Female; D005434:Flow Cytometry; D005500:Follow-Up Studies; D064368:Healthy Volunteers; D006801:Humans; D008297:Male; D008545:Melanoma / Q000378:metabolism / Q000473:pathology* / Q000628:therapy; D008558:Melphalan / Q000008:administration & dosage; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000378:metabolism / Q000473:pathology / Q000628:therapy; D009367:Neoplasm Staging; D011379:Prognosis; D011994:Recombinant Proteins / Q000627:therapeutic use*; D012509:Sarcoma / Q000378:metabolism / Q000473:pathology* / Q000628:therapy; D013234:Stem Cells / Q000187:drug effects / Q000378:metabolism / Q000473:pathology*; D014409:Tumor Necrosis Factor-alpha / Q000008:administration & dosage*; D040301:Vascular Endothelial Growth Factor Receptor-2 / Q000378:metabolism*; D055815:Young Adult
chemical_list: D011994:Recombinant Proteins; D014409:Tumor Necrosis Factor-alpha; D040301:Vascular Endothelial Growth Factor Receptor-2; D002945:Cisplatin; D008558:Melphalan