CCNE1 and breast cancer: For example, miRNAs, such as miR-497, miR-16, and miR-30c-2-3p, were reported to target and inhibit cell cycle regulator of G1-S transition, cyclin E1 leading to decreased cyclin E1 expression and suppression of proliferation by blocking BC cells from entering the S-phase of the cell cycle [89,90,91,92].