Figure 6.

Twist and Dermo1 promote colony formation in soft agar. C8 MEFs were infected with retroviruses that direct the expression of LacZ, Twist, Dermo1, or Bcl-2. Infected cells were plated in soft agar, and colony formation was assessed after 2 weeks (as indicated). The LacZ-expressing cells form only a few, small colonies. Cells infected with Twist, Dermo1, or Bcl-2 form large colonies similar to those that are observed on expression of dominant-interfering alleles of p53. Expression of Twist or Dermo1 enhances colony formation by approximately five to sevenfold.