Importance of T-cells and macrophages in the antitumor activity of carboxyethylgermanium sesquioxide (Ge-132).
The purpose of this study was to investigate the effective mechanisms of Ge-132, an organogermanium compound with immunomodulatory activity, on experimental murine ascites tumors. The antitumor effects of Ge-132 were observed when mice inoculated with Ehrlich carcinoma (allogeneic) or RL male 1 leukemia (syngeneic) cells were treated orally. However, Ge-132 had no activity on EL-4 lymphoma (syngeneic) or Meth A fibrosarcoma (syngeneic). The antitumor activity of Ge-132 was not observed when tumor-bearing mice were treated with trypan blue, carrageenan, or monoclonal anti-Thy 1.2 antibody. However, when natural killer (NK) cells were eliminated from mice bearing RL male 1 or Ehrlich ascites tumors by treatment with anti-asialo GM1 antiserum, the antitumor activity of the compound was unchanged. This suggests that Ge-132 was effective against certain ascites tumors regardless of whether the tumor was syngeneic or allogeneic. Furthermore, its effect might be expressed through host defense mechanisms, including macrophages and/or T-cells.
D000818:Animals; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D002286:Carcinoma, Ehrlich Tumor / Q000188:drug therapy* / Q000276:immunology / Q000473:pathology; D005260:Female; D005857:Germanium / Q000627:therapeutic use*; D007694:Killer Cells, Natural / Q000187:drug effects; D008212:Lymphocyte Depletion; D008264:Macrophages / Q000187:drug effects* / Q000276:immunology; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D009942:Organometallic Compounds / Q000627:therapeutic use*; D011422:Propionates; D013601:T-Lymphocytes / Q000187:drug effects* / Q000276:immunology
D000970:Antineoplastic Agents; D009942:Organometallic Compounds; D011422:Propionates; D005857:Germanium; C066750:propagermanium