PIK3R5 and in situ carcinoma: These CIS represent loci that are mutated in the process of tumorigenesis in the presence of an intact Cadm1 signaling pathway, and whose contribution to tumorigenesis is potentially rendered obsolete in the absence of Cadm1. Some of these genes, such as Pik3r5 and Malt1, have also been identified as CIS in leukemia/lymphomas from wildtype mice in other Sleeping Beauty transposon screens we have performed (unpublished data).