Moreover, given USP18 is a major negative regulator of the IFN signaling pathway, chronic myeloid leukemia (CML) USP18 deficiency cells were found to be more antigenic, driving increased activation of cytotoxic T lymphocyte (CTLs) and were also more susceptible to irradiation [38]. This evidence concerns the gene USP18 and chronic myelogenous leukemia, BCR-ABL1 positive.