Differences in gene expression of interaction partners of CDC2 in MCL subgroups. In this network figure, red indicates high expression and blue low expression in the subgroup "b" of the proliferation signature. White indicates no gene expression difference and grey the unavailability of the gene in our data set. "Cell division cycle 2" (CDC2) gene interacts in different manners with "cyclin D1" (CCND1), "cell division cycle 25C"(CDC25C), "proliferating cell nuclear antigen"(PCNA), "E2F transcription factor 1"(E2F1) and WEE1. CDC2 and CCND1 are both required for the G1/S transition. The genes WEE1 and CDC25C phosphorylate and dephosphorylate the complexes bound with CDC2 in a cell cycle regulating manner. The "proliferating cell nuclear antigen" (PCNA) is involved in DNA replication whereas "E2F transcription factor 1" (E2F1) controls cell cycle and mediates cell proliferation and apoptosis. A cell cycle regulated transcription activator "Nucleolin" (NCL) shows little difference.