Comparison of the effects of recombinant adenovirus-mediated expression ofwildtype p53 and p27(Kip1) on cell cycle and apoptosis in SUDHL-1 cells derived from anaplastic large cell lymphoma

Recombinant adenoviruses expressing wild-type p53 (AdWTp53) and p27(Kip1) ( Adp27) were used to compare the effects on cell cycle and apoptosis in SUDH L-1 cells derived from human anaplastic large cell lymphoma. Cells infected with AdWTp53 and Adp27 showed high level of wild-type p53 and p27(Kip1) ex pression, respectively. The expression of these proteins resulted in G1 arr est after 24 h of infection. Although the cells persisted in G1 arrest in b oth cell populations after 48 and 72 h of infection, the level of apoptosis assessed by TUNEL analysis was higher in cells infected with AdWTp53. Inte restingly, apoptosis was more pronounced in cells infected with Adp27 after the initial 24 h and reached a steady state at 48 and 72 h. A lower MOI of Adp27 resulted in G1 arrest associated with a low level of apoptosis in SU DHL-1 cells after 48 h of infection. This was correlated with lower express ion of p27(Kip1). We postulate that the time-lag and the different level of apoptosis occurring in SUDHL-1 cells infected with AdWTp53 and Adp27 are c learly related to the intrinsic biochemical pathways solicited. In this con text our study provides a model to investigate these pathways and better un derstand the biology of this particular lymphoma. Our data also support a p otential application of Adp27 for gene therapy of this lymphoma similarly t o AdWTp53 as previously shown.