• 1 January 1979
    • journal article
    • research article
    • Vol. 39  (5) , 1511-1517
Abstract
Ornithine decarboxylase (ODC) production was used as an indicator of mitotic activity in neoplastic cells removed from murine hosts at progressive stages of growth. Cells from 3 ascites cancers and 1 fibrosarcoma were tested and showed declining ODC production with progressive growth. The cells were incubated with serum or malignant effusion fluid taken from the murine hosts at progressive stages of growth. For 2-3 wk after tumor implantation, sera and, in particular, ascites fluids increasingly stimulated ODC production in cells at all stages of growth. With advancing disease, without the malignant growth having reached a stationary phase, the collected fluids decreasingly stimulated ODC production in the cells. The stimulating factor(s) in host serum and malignant effusion fluid were not tumor specific in the combination tested.