Pim1 enhances tumorigenicity of aggressive human prostate cancer cells (DU145) in vitro and in vivo. (A) Soft agar assay shows increased in vitro tumorigenicity of Pim1-expressing DU145 cells. When control or Pim1-expressing DU145 cells were subcutaneously grafted in nude mice (nu/nu), the latter developed larger tumor in size (B and C). (D) Kaplan-Meier survival analysis demonstrates significantly accelerated tumor onset by Pim1 expression. Numbers in the parentheses indicate the number of replicates or grafts in each group. *P < 0.01, **P < 0.05.