Induction of PTEN expression mediated by adenovirus(Ad-PTEN) in several types of cancer demonstrated to beeffective to downregulate PI3K/AKT pathway, consequently contributing toapoptosis induction, migration, and growth inhibition in tumor cell lines andtumor suppression in vivo (see summary data in Table S1).Nonetheless, this effect is more effective in cell lines with loss or mutatedPTEN in comparison to tumor cells carrying WTPTEN (Tanaka and Grossman,2003; Hamada et al., 1999;Tanaka et al., 2005; Rosser etal., 2004). This evidence concerns the gene PTEN and cancer.