The splicing factor SRSF1 [18] has a pleiotropic effect: it regulates splicing (enhancing or decreasing certain isoforms), regulates nonsense-mediated mRNA decay, has a role on RNA metabolism (translation), RNA protein binding, has a potential oncogenic role in cancer, regulates the mitosis among other processes [9, 19–21]. The gene discussed is SRSF1; the disease is cancer.