LKB1 expression in CT-2A tumor and in contra-lateral normal brain and influence of 40%CR. a) Influence of 40% dietary restriction on LKB1 protein expression. CT-2A tumor implantation and diet treatment was the same as mentioned above. Endogenous amount of LKB1 was analyzed. CT-2A tumor has no expression for LKB1 whereas normal brain expresses it. Moreover, 40% CR increased the expression of LKB1 in normal brain tissue. b) Ratio of LKB1 to β-actin. A significant (p < 0.05) increase in LKB1 expression has been noticed in the brain of CR mice. Tissues from 3 independent mice were analyzed.