[Suppression of tumor growth by peritoneal macrophages isolated from mice treated with carboxyethylgermanium sesquioxide (Ge-132)].
In a murine model it has been shown that the antitumor activity of carboxyethylgermanium sesquioxide (Ge-132) can be depleted by administration of macrophage (M phi) blockers. In the present study, the role that M phi play in the antitumor activity of the compound was investigated. Oral administration of Ge-132 in mice was demonstrated to be effective in activating M phi (Ge-132-cytotoxic M phi), and the cytotoxic activity of these M phi appeared in the peritoneal cavity of mice 48 hours after the oral administration of the compound. Co-cultivation of RL male-1 leukemia or Ehrlich carcinoma cells with Ge-132-cytotoxic M phi in vitro resulted in marked suppression of the growth of tumor cells. The transfer of peritoneal exudate cells (PEC), or purified M phi fractions of PEC from Ge-132-treated mice to mice bearing Ehrlich or RL male-1 ascites tumors resulted in significant protection. However, when the cytotoxic M phi were depleted by carbonyl-iron treatment in vitro, no antitumor effect was demonstrated in mice bearing Ehrlich or RL male-1 ascites tumors. Macrophage fractions obtained from PEC of Ge-132-treated mice exhibited an inhibitory effect against certain tumors both in vivo and in vitro suggesting that the antitumor effect of Ge-132 observed in vivo resulted from the activation of M phi.
D000284:Administration, Oral; D000818:Animals; D000970:Antineoplastic Agents / Q000008:administration & dosage / Q000494:pharmacology*; D002286:Carcinoma, Ehrlich Tumor / Q000276:immunology* / Q000473:pathology; D003602:Cytotoxicity, Immunologic; D005857:Germanium / Q000008:administration & dosage / Q000494:pharmacology*; D007942:Leukemia, Experimental / Q000276:immunology* / Q000473:pathology; D008114:Liver Neoplasms, Experimental / Q000276:immunology* / Q000473:pathology; D008262:Macrophage Activation / Q000187:drug effects; D008264:Macrophages / Q000276:immunology*; D051379:Mice; D009942:Organometallic Compounds / Q000008:administration & dosage / Q000494:pharmacology*; D010529:Peritoneal Cavity / Q000166:cytology; D011422:Propionates
D000970:Antineoplastic Agents; D009942:Organometallic Compounds; D011422:Propionates; D005857:Germanium; C066750:propagermanium