CCND2 and breast cancer: Overexpression of CCND2 has been linked to tumorigenesis and cancer progression, with aberrant expression or mutations identified in cancers such as thyroid cancer, lung cancer, and breast cancer (Park et al. 2010, Chen et al. 2018, Hung et al. 2018, Xia et al. 2018, Yuan et al. 2023, Jia et al. 2024).