Opposite to the role of USP19 as a tumor suppressor, recent work has also established that antagonism of USP19 expression conferred a prominent antiproliferative and antitumorigenic response in diverse neoplasms: Ewing sarcoma, gastric, breast and colorectal cancers (Gierisch et al., 2019; Dong et al., 2020; Rossi et al., 2021; Zhu et al., 2021), suggesting pro-tumorigenic roles in these tissues. Here, USP19 is linked to Ewing sarcoma.