Outgrowth of grafts containing different ratios of hormone-dependent and independent mouse mammary tumor cells.
The growth properties of grafts composed of different mixtures of hormone-dependent and independent GR mouse mammary tumor cells were investigated. Grafts containing only hormone-dependent mammary tumor cells yielded tumors in 4--6 weeks in estrone plus progesterone treated castrated mice, but not in castrated mice that were not treated with hormones. Grafts containing only autonomous mammary tumor cells yielded tumors in about 2 weeks in both hormone-treated and untreated castrated mice. Grafts containing mixtures of hormone-dependent and autonomous cells yielded tumors in 2 weeks both in hormone-treated and untreated castrates, even when the grafts contained predominantly hormone-dependent cells (up to 90%). These results indicate that the growth behavior of heterogeneous mammary tumor grafts that contain more than 10% autonomous cells, is essentially determined by these cells. Growth of the autonomous cells is not markedly affected by the presence of hormone-dependent cells in the grafts.
D000818:Animals; D004967:Estrogens / Q000502:physiology; D005260:Female; D008325:Mammary Neoplasms, Experimental / Q000188:drug therapy / Q000473:pathology*; D051379:Mice; D008815:Mice, Inbred Strains; D009368:Neoplasm Transplantation; D009376:Neoplasms, Hormone-Dependent / Q000473:pathology*; D011374:Progesterone / Q000502:physiology
D004967:Estrogens; D011374:Progesterone