Enhanced antitumor effect of recombinant human tumor necrosis factor in combination with recombinant human granulocyte colony-stimulating factor in BALB/c mice.
The synergistic antitumor effect of tumor necrosis factor (TNF) and granulocyte colony-stimulating factor (G-CSF) was investigated. G-CSF was administered subcutaneously to BALB/c mice inoculated with Meth-A cells at a dose of 2.5 micrograms/day for 5 consecutive days. When TNF (1 x 10(3) U) was administered intravenously to mice which had been pretreated with G-CSF, tumor growth showed a 74.1% inhibition 17 days after the tumor cell inoculation, compared to that of untreated mice. In this experiment, G-CSF significantly (P < 0.025) enhanced the antitumor effect of TNF. The in vitro cytotoxicity of TNF (10 U/ml) towards Meth-A cells was increased about 5.2-fold in the presence of neutrophils (E/T = 50) as compared to the cytotoxicity obtained with TNF alone. A combination of TNF and G-CSF (50 ng/ml) in the presence of neutrophils, resulted in a 2.1 times greater cytotoxicity against Meth-A cells as compared to that obtained without G-CSF. Significant augmenting effects of G-CSF on superoxide (O2-) production by TNF-stimulated neutrophils were observed. These observation suggest that the neutrophil plays an important role in the antitumor action of TNF on Meth-A cells, and that the antitumor effect of TNF is enhanced by combination with G-CSF.
Maeda
M
M
Department of Internal Medicine (Section 4), Sapporo Medical College.
Watanabe
N
N
Tsuji
N
N
Tsuji
Y
Y
Okamoto
T
T
Sasaki
H
H
Akiyama
S
S
Niitsu
Y
Y
D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology; D004354:Drug Screening Assays, Antitumor; D004357:Drug Synergism; D005260:Female; D016179:Granulocyte Colony-Stimulating Factor / Q000008:administration & dosage / Q000494:pharmacology*; D007958:Leukocyte Count; D051379:Mice; D008807:Mice, Inbred BALB C; D009368:Neoplasm Transplantation; D009504:Neutrophils / Q000187:drug effects; D011994:Recombinant Proteins / Q000494:pharmacology; D013481:Superoxides / Q000032:analysis; D014407:Tumor Cells, Cultured; D014409:Tumor Necrosis Factor-alpha / Q000008:administration & dosage / Q000494:pharmacology*
D000970:Antineoplastic Agents; D011994:Recombinant Proteins; D014409:Tumor Necrosis Factor-alpha; D013481:Superoxides; D016179:Granulocyte Colony-Stimulating Factor