Screening for compounds with morphological reversion activity on transformed cells.


It is known that products of oncogenes such as Src have transforming activity when expressed in mammalian cells. When srcts-NRK cells were cultured at 32 oC, spherical transformed cells were observed. In the other hand, flat normal cells were appeared at 39 oC in place of spherical cells, since srcts is inactivated at this temperature. Some compounds that have src inhibitory activity induce morphological reversion of srcts-NRK cells from spherical transformed cells to normal cells at 32 oC. Srcts-NRK cells maintained at 32 oC were seeded into a 96-well microtiter plate (2x104 cells/200ul/well) and cultured for 4 hours at 32 oC in 5 % CO2 atmosphere. Various concentrations of the compounds were added to srcts-NRK cells and the morphological reversion activity on srcts-NRK cells was measured under a microscope after 17 hours incubation at 32 oC. The activity were represented as the rate of normal flat cells in total cells.





Morphology of srcts-NRK cells.
Cells cultured at 39 oC(nonpermissive temperature) took the normal flat morphology (A). At 32 oC(permissive temperature), the cells took the transformed morphology (B). The transformed phenotype was reversed to the normal by the treatment with 17 ug/ml of phosmidosine. (C). (Ref:2)


  1. H. Takahashi, H. Osada, H. Koshino, M. Sasaki, R. Onose, M. Nakakoshi, M. Yoshihama, K. Isono
    Reveromycins, new inhibitors of eukaryotic cell growth. II. Biological activities.
    J. Antibiotics, 45, 1414-1419 (1992).

  2. N. Matsuura, R. Onose, H. Osada
    Morphology reversion activity of phosmidosine and phosmidosine B, a newly isolated derivative, on src transformed NRK cells.
    J. Antibiotics, 49, 361-365 (1996).

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