The tumorigenicity of LMW-E requires CDK2–associated kinase activity.

Athymic mice were injected with 1×107 76NE6-TetR cells with inducible expression for empty vector, EL, LMW-E, ELR130A, and LMW-ER130A. Doxycycline was added to drinking water containing 1% sucrose 24 hours after injection and replaced twice weekly. The diameter of the tumors were measured and recorded weekly. Tumor incidence rate was estimated with exact 95% confidence intervals and Fisher's exact tests were used to compare tumor incidence rate between/among groups (*p<0.0001: LMW-E 0 vs. LMW-E 500; vector 500 vs. LMW-E 500; EL 500 vs. LMW-E 500; LMW-E 500 vs. ELR130A 500; LMW-E 500 vs. LMW-ER130A).