MEF2C and acute lymphoblastic leukemia: MEF2C is also overexpressed in ETP-ALLs but it was upregulated in only one CD2-Lmo2 T-ALL, concordant with the only leukemia overexpressing Tal1. We previously found that Mef2c was a cooperating oncogene with Lmo2 in AKXD T-ALLs where Tal1 upregulation was prominent suggesting that Mef2c may be co-mutated with Tal1 in human cases as well [26].