Generation and control of metastasis in experimental tumor systems; inhibition of experimental metastases by a tilorone analogue.
The role of the chemical compound RMI 10,874DA (3,6-bis[2-(dimethylamino)-ethoxyl]-9H-xanthene-9-one dihydrochloride) in the abrogation of the metastatic spread of tumor cells was studied. Pre-treatment of BALB/c mice with the RMI 10,874DA compound (referred to below as tilorone analogue) completely eliminated lung colonization of an H-2-negative (GR9.B9) MCA-induced fibrosarcoma clone in an experimental metastasis assay. Other murine tumors, including H-2-positive and H-2-negative chemically induced fibrosarcoma clones and B16 melanoma, were also sensitive to the treatment; orally administered tilorone analogue given one day before the i.v. injection of tumor cells markedly inhibited lung colonization. The effect was not due to direct toxicity of tilorone analogue on tumor cells, but instead it was dependent on NK cells; this was suggested by the finding that anti-asialo GM, treatment of mice abrogated the effect of tilorone analogue. Kinetic studies of splenic NK activity in tilorone-treated mice showed a rapid boosting of NK-cell activity, the greatest stimulation occurring the day before removal of splenocytes for 51Cr-release assay against YAC-I target cells. These kinetics correlated with the inhibition of in vivo lung colonization after tilorone analogue treatment. Inhibition of experimental tumor metastasis was dose-dependent and was observed when animals were treated the day before or the day after tumor-cell injection. Furthermore, repeated treatment of mice with this tilorone analogue significantly reduced lung colonization.
Department of Análisis Clínicos e Inmunología, Hospital Virgen de las Nieves, Universidad de Granada, Spain.
I
I
Algarra
M
M
Pérez
P
P
Höglund
J J
JJ
Gaforio
H G
HG
Ljunggren
F
F
Garrido
D000818:Animals; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D005677:G(M1) Ganglioside / Q000276:immunology; D007106:Immune Sera / Q000494:pharmacology; D007694:Killer Cells, Natural / Q000187:drug effects / Q000502:physiology; D008175:Lung Neoplasms / Q000188:drug therapy / Q000556:secondary; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D009362:Neoplasm Metastasis / Q000517:prevention & control*; D009374:Neoplasms, Experimental / Q000188:drug therapy* / Q000473:pathology / Q000556:secondary*; D013154:Spleen / Q000166:cytology / Q000187:drug effects; D013994:Tilorone / Q000031:analogs & derivatives*; D013997:Time Factors; D014966:Xanthenes / Q000493:pharmacokinetics / Q000627:therapeutic use; D044004:Xanthones
D000970:Antineoplastic Agents; D007106:Immune Sera; D014966:Xanthenes; D044004:Xanthones; D005677:G(M1) Ganglioside; C081584:RMI 10874DA; C018835:asialo GM1 ganglioside; D013994:Tilorone