Tumoricidal activity of high-dose tumor necrosis factor-alpha is mediated by macrophage-derived nitric oxide burst and permanent blood flow shutdown.
This study investigates the role of tumor nitric oxide (NO) and vascular regulation in tumor ulceration following high-dose tumor necrosis factor-alpha (TNF) treatment. Using TNF-responsive (MethA) and nonresponsive (LL2) mouse tumors, tumor NO concentration was measured with an electrochemical sensor and tumor blood flow by Doppler ultrasound. Mice were also pretreated with a selective inducible nitric oxide synthase (iNOS) inhibitor, 1400 W. Tumors harvested from TNF-treated mice were cryosectioned and immunostained for murine macrophages, or/and iNOS. MethA tumor-bearing mice were depleted of macrophages. Pre- and post-TNF tumor NO levels were measured continuously, and mice were followed for gross tumor response. In MethA tumors, TNF caused a 96% response rate, and tumor NO concentration doubled. Tumor blood flow decreased to 3% of baseline by 4 hr and was sustained at 24 hr and 10 days post-TNF. Selective NO inhibition with 1400 W blocked NO rise and decreased response rate to 38%. MethA tumors showed tumor infiltration by macrophages post-TNF and the pattern of macrophage immunostaining overlapped with iNOS immunostaining. Depletion of macrophages inhibited tumor NO increase and response to TNF. LL2 tumors had a 0% response rate to TNF and exhibited no change in NO concentration. Blood flow decreased to 2% of baseline by 4 hr, recovered to 56% by 24 hr and increased to 232% by 10 days. LL2 tumors showed no infiltration by macrophages post-TNF. We conclude that TNF causes tumor infiltrating, macrophage-derived iNOS-mediated tumor NO rise and sustained tumor blood flow shutdown, resulting in tumor ulceration in the responsive tumor.
Menon
Chandrakala
C
Department of Surgery, University of Pennsylvania, Philadelphia, PA.
Bauer
Todd W
TW
Department of Surgery, University of Pennsylvania, Philadelphia, PA.
Kelley
Scott T
ST
Department of Surgery, University of Pennsylvania, Philadelphia, PA.
Raz
Dan J
DJ
Department of Surgery, University of Pennsylvania, Philadelphia, PA.
Bleier
Joshua I
JI
Department of Surgery, University of Pennsylvania, Philadelphia, PA.
Patel
Krina
K
Department of Surgery, University of Pennsylvania, Philadelphia, PA.
Steele
Kirsten
K
Department of Surgery, University of Pennsylvania, Philadelphia, PA.
Prabakaran
Indira
I
Department of Surgery, University of Pennsylvania, Philadelphia, PA.
Shifrin
Alexander
A
Department of Surgery, University of Pennsylvania, Philadelphia, PA.
Buerk
Donald G
DG
Department of Physiology, University of Pennsylvania, Philadelphia, PA.
Sehgal
Chandra M
CM
Department of Radiology, University of Pennsylvania, Philadelphia, PA.
Fraker
Douglas L
DL
Department of Surgery, University of Pennsylvania, Philadelphia, PA.
D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology*; D015815:Cell Adhesion Molecules / Q000378:metabolism; D045744:Cell Line, Tumor; D004002:Clodronic Acid / Q000008:administration & dosage / Q000494:pharmacology; D019040:E-Selectin / Q000378:metabolism; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005354:Fibrosarcoma / Q000098:blood supply* / Q000188:drug therapy* / Q000201:enzymology / Q000378:metabolism; D015971:Gene Expression Regulation, Enzymologic; D007150:Immunohistochemistry; D008081:Liposomes; D008264:Macrophages / Q000378:metabolism*; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D009569:Nitric Oxide / Q000378:metabolism*; D052247:Nitric Oxide Synthase Type II / Q000378:metabolism; D012039:Regional Blood Flow; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*; D019010:Vascular Cell Adhesion Molecule-1 / Q000378:metabolism
D000970:Antineoplastic Agents; D015815:Cell Adhesion Molecules; D019040:E-Selectin; D008081:Liposomes; D014409:Tumor Necrosis Factor-alpha; D019010:Vascular Cell Adhesion Molecule-1; D004002:Clodronic Acid; D009569:Nitric Oxide; D052247:Nitric Oxide Synthase Type II