CCND1 and breast cancer: Besides, many proteins involved in tumor development in BC also showed high degree values, such as CASP3 and epidermal growth factor receptor (EGFR) (degrees of both are 47), MYC and VEGFA (degrees of both are 45), cyclin D1 (CCND1) (degree = 40), erb-b2 receptor tyrosine kinase 2 (ERBB2) (degree = 37), mechanistic target of rapamycin kinase (mTOR) (degree = 34), PPARG (degree = 33) and so on.