BCL2 and leukemia: Evidence for a role for ZFP36L1 in BCL2 mRNA degradation came from mRNA degradation analysis following actinomycin D treatment in two different murine leukemia BCL1 cell lines, one of which had been stably transduced with a lentiviral vector expressing Zfp36l1-ShRNA and a second BCL1 cell line that had been stably transduced with control (empty vector) lentivirus [9].