CDK4 and neoplasm: While we observed little to no difference in the expression levels of p16 (Cdkn2a) and Ccne1 in tumors of these genotypes, we did observe a decrease in Cdk4 (4.8-fold p<0.01) and a decrease in Ccnd1 mRNA (∼5.8-fold; p<0.01) in the Brg1-KO tumor cells compared with the WT tumor cells.