CCND1 is more frequently deregulated than CCND2 and CCND3 in both solid and haematological cancers [46], and is over-expressed and upregulated in multiple cancers, including head and neck squamous carcinoma [47], mantle cell lymphoma [48], pancreatic cancer [49], melanoma [50], non-small cell lung cancer [51], gastric cancer [52], colorectal cancer [53], endometrial cancer [54], and over 50% of human breast cancers [55]. Here, CCND2 is linked to breast cancer.