DUX4 and sarcoma: Another study using a xenograft mouse model orthotopically injected with NIH3T3 mouse fibroblasts expressing CIC–DUX4 showed that the CIC–DUX4 proteins promote tumor growth and metastasis via the upregulation of CCNE1 and ETV4, respectively, suggesting that these proteins drive tumorigenesis and metastasis in sarcomas via distinct regulatory programs39.