CCND1 and precursor B-cell acute lymphoblastic leukemia: Alteration of CDK-encoding genes or their partner cyclins can lead to their overexpression, amplification and translocation, e.g., cyclin D1 alterations are observed in chronic lymphocytic leukemia (CLL), B-cell acute lymphocytic leukemia (B-ALL), mantle cell lymphoma (MCL), and multiple myeloma (MM).