Driven by the high protein levels of SF3B1 in HR T-ALL samples and E7107-inflicted alterations in DDR, we used combinations of splicing factor inhibitors and chemotherapeutic drugs such as topoisomerase I inhibitors, topoisomerase II inhibitors, and mitoxantrone as single-agent treatments or in combination with E7107 to assess growth inhibition (Fig. 5, A to D, and fig. Here, SF3B1 is linked to acute lymphoblastic leukemia.