CHANGES IN MICROFILAMENT AND FOCAL ADHESION DISTRIBUTION WITH LOSS OF ANDROGEN RESPONSIVENESS IN CULTURED MAMMARY-TUMOR CELLS

Google Scholar
  • 1 January 1981
    • journal article
    • research article
    • Vol. 41  (1) , 263-269
Abstract
Shionogi 115 mouse mammary tumor cells were studied. The androgen-unresponsive cells had extensive, prominent microfilament bundles and focal adhesions on the lower cell surface, and also showed strict anchorage dependence for growth. Microfilament bundles and focal adhesions were absent from androgen-responsive cells, which were able to grow in suspension culture. Differences were also apparent in fibronectin expression, the androgen-unresponsive cells having more of this glycoprotein detectable on their surfaces than the androgen-responsive cells. The androgen-responsive and -unresponsive cells had similar microtubule arrays. During the transition from the androgen-responsive to the androgen-unresponsive phenotype, the androgen-responsive cells gradually took on the characteristics of androgen-unresponsive cells as judged by cellular morphology or the presence of focal adhesions and microfilament bundles. At intermediate stages in this process, characteristics of both cell types were visible in the cell populations. At the stage in which all androgen-responsive characteristics were lost, the cells were no longer androgen sensitive. The loss of androgen responsiveness in Shionogi 115 mouse mammary tumor cells is correlated with changes at the cell membrane and the microfilament component of the cytoskeleton.