International Journal of Molecular Sciences Review The Roles of Cyclin-Dependent Kinases in Cell-Cycle Progression and Therapeutic Strategies in Human Breast Cancer 1,2, 1,2, 1,2, 1,2 1,2 Lei Ding y, Jiaqi Cao y, Wen Lin y, Hongjian Chen , Xianhui Xiong , Hongshun Ao 1,2, Min Yu 1,2, Jie Lin 1,2 and Qinghua Cui 1,2,* 1 Lab of Biochemistry & Molecular Biology, School of Life Sciences, Yunnan University, Kunming 650091, China;
[email protected] (L.D.);
[email protected] (J.C.);
[email protected] (W.L.);
[email protected] (H.C.);
[email protected] (X.X.);
[email protected] (H.A.);
[email protected] (M.Y.);
[email protected] (J.L.) 2 Key Lab of Molecular Cancer Biology, Yunnan Education Department, Kunming 650091, China * Correspondence:
[email protected] The authors contributed equally to this work. y Received: 31 December 2019; Accepted: 24 February 2020; Published: 13 March 2020 Abstract: Cyclin-dependent kinases (CDKs) are serine/threonine kinases whose catalytic activities are regulated by interactions with cyclins and CDK inhibitors (CKIs). CDKs are key regulatory enzymes involved in cell proliferation through regulating cell-cycle checkpoints and transcriptional events in response to extracellular and intracellular signals. Not surprisingly, the dysregulation of CDKs is a hallmark of cancers, and inhibition of specific members is considered an attractive target in cancer therapy. In breast cancer (BC), dual CDK4/6 inhibitors, palbociclib, ribociclib, and abemaciclib, combined with other agents, were approved by the Food and Drug Administration (FDA) recently for the treatment of hormone receptor positive (HR+) advanced or metastatic breast cancer (A/MBC), as well as other sub-types of breast cancer.