Dalpiciclib (SHR-6390) is a highly selective, orally bioavailable CDK4/6 inhibitor with comparable potencies against CDK4 (IC50=12.4 nM) and CDK6 (IC50=9.9 nM). Dalpiciclib exerts potent antitumor activity in esophageal squamous cell carcinoma by inhibiting phosphorylated tumor-suppressor retinoblastoma protein (Rb) and inducing G1 cell cycle arrest[1][2].
Dalpiciclib (SHR-6390) (0-4 μM) inhibits cell proliferation in a dose-dependent manner[2].Dalpiciclib (24 hours) significantly blocks phosphorylation of Rb at serine 780 in relative sensitive Eca 109 and KYSE-510 cell lines, but not in relative resistant Eca 9706 cell line.Dalpiciclib induces cell cycle arrest at G1 phase in Eca 109 and KYSE-510 cell lines[2].
Dalpiciclib (SHR-6390) (150 mg/kg; oral gavage; weekly for 3 weeks) shows antitumor activity against ESCC xenografts[2].Dalpiciclib combines with Paclitaxel (PTX) or Cisplatin (CDDP) offered synergistic inhibitory effects in ESCC xenografts[2].
[1]. Zhang P, et al. A phase 1 study of dalpiciclib, a cyclin-dependent kinase 4/6 inhibitor in Chinese patients with advanced breast cancer. Biomark Res. 2021;9(1):24. Published 2021 Apr 12.
[2]. Wang J, et al. CDK4/6 inhibitor-SHR6390 exerts potent antitumor activity in esophageal squamous cell carcinoma by inhibiting phosphorylated Rb and inducing G1 cell cycle arrest. J Transl Med. 2017;15(1):127. Published 2017 Jun 2.