Although Malat1 is not essential in living mice maintained under normal breeding conditions (Nakagawa et al., 2012; Zhang et al., 2012), MALAT1 has an important role in the study of human cancer: MALAT1 is overexpressed in many solid tumors (Lin et al., 2007; Gutschner et al., 2013a). Here, MALAT1 is linked to cancer.