CDKN1A and breast cancer: Moreover, ellagic acid present in pomegranate can inhibit the proliferation of breast cancer cells MCF-7 by increasing the expression of cyclin-dependent kinase inhibitors (p21, Cip1, p15 and p19) (44), as well as proliferation of ovarian cells ES-2 and PA-1 by increasing p53 and p21 levels, leading to cell cycle arrest in the G1 phase (45).