PML and cancer: Although a developmental role for TRIM19 in the brain remains to be uncovered, SUMOylation [a suggested function of TRIM19 (Chu and Yang, 2011; Guo et al., 2014)] is extensive during brain development, particularly in the hippocampus, and TRIM19 has been implicated in driving the stem-like properties in the context of cancer (Henley et al., 2014; Zhou and Bao, 2014).