Toggle Main Menu Toggle Search

Open Access padlockePrints

Pre-clinical evaluation of cyclin-dependent kinase 2 and 1 inhibition in anti-estrogen-sensitive and resistant breast cancer cells

Lookup NU author(s): Dr Nicola Johnson, Dr Johanne Bentley, Lan Wang, Professor Herbie Newell, Professor Craig Robson, Professor Nicola CurtinORCiD



BACKGROUND: Cellular proliferation, driven by cyclin-dependent kinases (CDKs) and their cyclin partners, is deregulated in cancer. Anti-estrogens, such as tamoxifen, antagonise estrogen-induced ER alpha transactivation of cyclin D1, resulting in reduced CDK4/6 activity, p27(Kip1)-mediated inhibition of CDK2 and growth arrest. We hypothesised that direct inhibition of CDK2 and CDK1 may overcome the major clinical problem of anti-estrogen resistance. METHODS: The cellular effects of CDK2/1 siRNA knockdown and purine-based CDK2/1 inhibitors, NU2058 and NU6102, were measured in anti-estrogen-sensitive and resistant breast cancer cell lines. RESULTS: CDK2 knockdown caused G1 accumulation, whereas CDK1 depletion caused G2/M slowing, and dual CDK1/2 depletion resulted in further G2/M accumulation and cell death in both anti-estrogen-sensitive and resistant cells, confirming CDK2 and CDK1 as targets for breast cancer therapy. In contrast to tamoxifen, which only affected hormone-sensitive cells, NU2058 and NU6102 reduced CDK2-mediated phosphorylation of pRb, E2F transcriptional activity and proliferation, ultimately resulting in cell death, in both anti-estrogen-sensitive and resistant cells. Both drugs caused G2/M arrest, reflective of combined CDK2/1 knockdown, with a variable degree of G1 accumulation. CONCLUSION: These studies confirm the therapeutic potential of CDK2 and CDK1 inhibitors for cancer therapy, and support their use as an alternative treatment for endocrine-resistant breast cancer. British Journal of Cancer (2010) 102, 342-350. doi:10.1038/sj.bjc.6605479 Published online 15 December 2009 (C) 2010 Cancer Research UK

Publication metadata

Author(s): Johnson N, Bentley J, Wang LZ, Newell DR, Robson CN, Shapiro GI, Curtin NJ

Publication type: Article

Publication status: Published

Journal: British Journal of Cancer

Year: 2010

Volume: 102

Issue: 2

Pages: 342-350

Date deposited: 15/07/2010

ISSN (print): 0007-0920

ISSN (electronic): 1532-1827

Publisher: Nature Publishing Group


DOI: 10.1038/sj.bjc.6605479


Altmetrics provided by Altmetric


Funder referenceFunder name
Breast Cancer Campaign
Cancer Research UK
P20 CA090578NIH
P50 CA089393NIH
R01 CA90687NIH