It is interesting to note that the EBNA1-EMPTY plasmid was lost in vivo, even though it expresses the viral tethering protein EBNA1 and we did not see an increase in EBNA1 expression when the AGS-EBNA1-BART in vitro lines grew as tumors in the mice (not shown) Together these observations suggest that EBNA1 does not provide a detectable advantage to tumor growth in our system. Here, PROS1 is linked to neoplasm.