On the other hand, BCR stimulation with external ligand has been shown to increase the expression of the cell cycle regulators MYC, CCND2, and CDK4 and to increase the percentage of CLL cells in the G1 phase of the cell cycle, suggesting that interactions with external autoantigens may provide the initial stimulus required for leukemic cell proliferation [76,77,78]. The gene discussed is BCR; the disease is B-cell chronic lymphocytic leukemia.