Adenovirus-mediated wild-type p53 gene transfer induces apoptosis and inhibits proliferation of human uveal melanoma cells

Purpose. To test the effect of a replication-deficient adenovirus (Ad) vector carrying wild-type p53 cDNA (AdCMV.p53) on the growth of 3 human uveal melanoma cell lines: SP-6.5, MKT-BR and OMM-1. Methods. Endogenous p53 mutations were assessed by PCR-SSCP on exons 5 to 9 of the p53 gene. Cells were infected eather with AdCMV.p53, with the control virus AdCMV.Null. (100 pfu/cell) or were uninfected. Expression of p53 was detected by Western Blot up to 7 days after infection. Proliferation was assessed by cell counting. The occurrence of apoptosis was evaluated by Tdt Biotin dUTP Nick-end Labeling (TUNEL) test and DNA gel electrophoresis. Results. Endogenous p53 mutations were detected only in exons 5 and 8 on OMM-1 cells. AdCMV.p53 infection enhanced p53 expression vs both infected and uninfected controls at 1, 3, 5 and 7 days after the beginning of experiments. Both infected and uninfected controls exhibited similar proliferation rates and at 3 days AdCMV.p53-infected cells were 27.3+-2.7%, 54.4+-6.5% and 16.3+-1.6% of controls for SP-6.5, MKT-BR and OMM-1 cell lines respectively (p