There is precedence for this observation, as several core spliceosome components have been reported to regulate alternative splicing in addition to serving as components of the canonical spliceosome, and spliceosome components including SF3B1, U2AF1, SRSF2 and hnRNPA1, among others, are often targeted by somatic mutation in cancer [124,125,126]. This evidence concerns the gene HNRNPA1 and cancer.