DETECTION OF INAPPARENT NODULE-TRANSFORMED CELLS IN MAMMARY-GLAND TISSUES OF VIRGIN FEMALE BALB-CFC3H MICE

  • 1 January 1978
    • journal article
    • research article
    • Vol. 38  (7) , 2103-2111
Abstract
Inapparent nodule-transformed cells were recovered from morphologically normal mammary tissue from virgin female BALB/cfC3H/Crgl (mouse mammary tumor-positive) mice before the appearance of hyperplastic alveolar nodules (HAN) or tumors, by the cell dissociation technique. Mammary tissues were dissociated by collagenase (0.1%), hyaluronidase (0.1%) and pronase (1.25%). Aliquots of 105 viable cells in 0.01 ml medium were injected into the gland-free mammary fat pads of 3-wk-old female syngeneic mice. After 10 wk the outgrowths were examined and classified as ductal, HAN, tumor or combinations of these types. The presence of HAN outgrowths indicated the presence of nodule-transformed cells in the donor mammary tissues. Nodule-transformed cells were recovered from 2-mo.-old donors, and the number of HAN outgrowths increased with donor age. Overt HAN and tumors did not appear in virgin female BALB/cfC3H/Crgl mice younger than 8-9 mo. of age. Inapparent nodule-transformed cells occurred long before the appearance of HAN or tumors and the numbers of transformed cells increased with donor age.