Fig. 5: Transcriptional effects of TFCP2 fusions.

a Relative FUS-TFCP2 and ALK mRNA expression in MCF10A cells stably transduced with FUS-TFCP2. Mean ± SEM (n = 3 independently transduced cell lines). Source data are provided in the Source Data file. b Number of genes significantly deregulated in MCF10A and SCP-1 cells transduced with FUS-TFCP2 or EWSR1-TFCP2 versus cells transduced with EV (log2(fold-change) >1.0 or <–1.0), as determined by RNA-seq. c Genes significantly deregulated in MCF10A and SCP-1 cells transduced with FUS-TFCP2 or EWSR1-TFCP2 versus cells transduced with EV (log2(fold-change) >1.0 or <–1.0 in at least three cell lines), as determined by RNA-seq. d Expression of genes from c in FUS/EWSR1-TFCP2-positive sarcoma samples, indicated as percentiles of expression across the entire MASTER cohort. e, f Genome browser images of ALK (e) and TERT (f) showing enrichment peaks obtained by ACT-seq with an anti-HA antibody (Cell Signaling) in MCF10A cells stably expressing EV, HA-TFCP2, or HA-FUS-TFCP2. g Genome browser image showing aberrant transcription originating from the second intron of TERT in patient TFCP2-HD-1. The first two exons were not transcribed. Instead, multiple novel intronic transcription start sites (red alignments) and antisense transcription (blue reads) were found around putative TFCP2 binding sites (bottom) detected by HOMER using the known Tcfcp2l1 binding motif. h Domain structure of full-length TERT (top) and the TERT variant predicted to be translated from mRNA lacking exons 1 and 2 (bottom). The domain structure was adapted from Chan et al.⁶⁵. CTE C-terminal extension, RT reverse transcriptase, TEN TERT-essential N-terminal, TRBD telomerase RNA-binding domain. i Western blot with tumor tissue from five patients and HeLa cells with an antibody binding to the C-terminus of TERT. Protein masses in kDa are shown on the left. Uncropped blots are provided in the Source Data file.