CCND1 and cancer: Recently, it has been increasingly recognized that splicing dysregulation can lead to cancer because alternative splicing usually changes the function of translated proteins, potentially creating oncogenes or inactivating tumor suppressor genes.8 For instance, previous studies have reported that Cyclin D1 (CCND1) underwent alternative splicing, resulting in the generation of a special CCND1 isoform, cyclin D1b, which lacked Thr-286.