EWSR1 and desmoplastic small round cell tumor: Strong nuclear staining for the WT1 C-terminus was detected in all samples probed (Fig. 5A), most likely representing EWS-WT1 in these novel DSRCT models, as a recent transcriptome profiling study has confirmed a lack of native WT1 transcripts in DSRCT (Hingorani et al., 2020).