title: Tumoricidal activity of high-dose tumor necrosis factor-alpha is mediated by macrophage-derived nitric oxide burst and permanent blood flow shutdown.
abstract: 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.
authors.affiliation: Department of Surgery, University of Pennsylvania, Philadelphia, PA.
authors.forename: Chandrakala
authors.initials: C
authors.lastname: Menon
authors.affiliation: Department of Surgery, University of Pennsylvania, Philadelphia, PA.
authors.forename: Todd W
authors.initials: TW
authors.lastname: Bauer
authors.affiliation: Department of Surgery, University of Pennsylvania, Philadelphia, PA.
authors.forename: Scott T
authors.initials: ST
authors.lastname: Kelley
authors.affiliation: Department of Surgery, University of Pennsylvania, Philadelphia, PA.
authors.forename: Dan J
authors.initials: DJ
authors.lastname: Raz
authors.affiliation: Department of Surgery, University of Pennsylvania, Philadelphia, PA.
authors.forename: Joshua I
authors.initials: JI
authors.lastname: Bleier
authors.affiliation: Department of Surgery, University of Pennsylvania, Philadelphia, PA.
authors.forename: Krina
authors.initials: K
authors.lastname: Patel
authors.affiliation: Department of Surgery, University of Pennsylvania, Philadelphia, PA.
authors.forename: Kirsten
authors.initials: K
authors.lastname: Steele
authors.affiliation: Department of Surgery, University of Pennsylvania, Philadelphia, PA.
authors.forename: Indira
authors.initials: I
authors.lastname: Prabakaran
authors.affiliation: Department of Surgery, University of Pennsylvania, Philadelphia, PA.
authors.forename: Alexander
authors.initials: A
authors.lastname: Shifrin
authors.affiliation: Department of Physiology, University of Pennsylvania, Philadelphia, PA.
authors.forename: Donald G
authors.initials: DG
authors.lastname: Buerk
authors.affiliation: Department of Radiology, University of Pennsylvania, Philadelphia, PA.
authors.forename: Chandra M
authors.initials: CM
authors.lastname: Sehgal
authors.affiliation: Department of Surgery, University of Pennsylvania, Philadelphia, PA.
authors.forename: Douglas L
authors.initials: DL
authors.lastname: Fraker
mesh_terms: 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
chemical_list: 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