Potential through simplicity: thymidine kinase-1 as a biomarker for CDK4/6 inhibitors


We describe a potential role for thymidine kinase-1, a general marker of cellular proliferation, to act as a prognostic biomarker in patients receiving CDK4/6 inhibitors for advanced hormone receptor-positive, HER2-negative breast cancer, with early data suggesting that it may also provide early indication of treatment response.

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Both authors drafted and revised the paper and approved the final version for publication.

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Correspondence to Luca Malorni.

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Competing interests

L.M. has received research support from Novartis and Pfizer and is a consultant for Eli Lilly, Pfizer, and Novartis. Both authors have academically collaborated with Biovica International without any financial remuneration or contractual agreement.

Funding information

This work was partially supported by a grant from the Breast Cancer Research Foundation (grant number BCRF 19-037) and by a grant from Fondazione AIRC (IG 22869).

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McCartney, A., Malorni, L. Potential through simplicity: thymidine kinase-1 as a biomarker for CDK4/6 inhibitors. Br J Cancer 123, 176–177 (2020). https://doi.org/10.1038/s41416-020-0858-y

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