Matches in SemOpenAlex for { <https://semopenalex.org/work/W2741832760> ?p ?o ?g. }
Showing items 1 to 97 of
97
with 100 items per page.
- W2741832760 endingPage "2340" @default.
- W2741832760 startingPage "2340" @default.
- W2741832760 abstract "Abstract Selective CDK4/6 inhibition is now part of standard treatment for HR+ breast cancer. There is a pressing need for a practical biomarker that can provide early indication of the biologic activity of these agents and correlate with clinical outcome. Expression of thymidine kinase (TK) occurs in actively proliferating cells, is E2F-dependent and is downregulated after CDK4/6 inhibitor-mediated G1 arrest. Here, we have investigated TK activity (TKA) as a pharmacodynamic marker for CDK4/6 inhibition in both preclinical and clinical contexts and demonstrate the potential of this assay as CDK4/6 inhibitors are further developed. TKA in response to the CDK 4/6 inhibitor palbociclib (palbo) was studied in cell culture, mouse models and samples from clinical studies. TKA was determined by the DiviTum Assay (Biovica, Sweden). In culture, the intracellular TKA and TK release in response to palbo were determined by analysis of cellular extracts and tissue culture media. In vivo, mice bearing human xenografts were treated with vehicle or palbo to determine effects on TKA in serum and in tumor extracts. Finally, serum TKA (s-TKA) was assayed in patient samples procured before and after palbo treatment in a Phase 1 study of palbo and the MEK inhibitor PD0325901 (NCT02022982). Palbo was administered on 3/4 (21 of every 28 days) or 4/4-week (continuous) schedules. In K562 cells, intracellular TKA levels exhibited a clear dose response to palbo. Reductions in TKA were seen at lower drug concentrations than those affecting cell viability. Similar results were observed in MCF-7 xenografts, where lower TKA in serum and tumor was observed after palbo treatment, whereas in E0771 xenografts, no change in TKA was observed. Clinically, serum samples were obtained before and at various time points after palbo exposure in 20 cancer patients. One patient, who discontinued study treatment at the end of cycle 1, demonstrated an increase in s-TKA. In contrast, for the other 19 patients, there was a marked decrease in s-TKA at day 21. Pre-treatment s-TKA values were higher than C1D21 (paired t-test, p<.0001). In 11 patients there was a reduction in s-TKA to below the assay detection limit. Five patients exhibited a reduction in s-TKA within the working range, with mean residual activity at day 21 of 32%. In the 6 patients receiving continuous palbo, s-TKA remained low after day 21. Of the 14 patients on the 3/4-week schedule, 9 exhibited an increasing level of s-TKA between day 21 and day 1 of cycle 2, consistent with reversible effects of palbo on cell cycle progression after cessation of exposure. These data suggest that s-TKA reflects MOA response to the selective CDK4/6 inhibitor palbo. The DiviTum assay may provide a practical, non-invasive tool for monitoring the effects of CDK4/6 inhibitors in both preclinical models and patients. We plan inclusion of the assay into additional studies to determine whether the assay can predict clinical outcome or portend development of resistance. Citation Format: Geoffrey Shapiro, Magnus Neumuller, Sara Lööf, Smaranda Bacanu, Takahiro Seki, John Hilton, Khan Do, Nicole Chau, Leena Gandhi, Joseph W. Gibson, Robert Distel, Pawel Niekrasz, Edward M. Suh, Mattias Bergqvist. Thymidine kinase activity as a response marker for CDK 4/6 inhibition [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2340. doi:10.1158/1538-7445.AM2017-2340" @default.
- W2741832760 created "2017-08-08" @default.
- W2741832760 creator A5019319557 @default.
- W2741832760 creator A5020504047 @default.
- W2741832760 creator A5036317188 @default.
- W2741832760 creator A5037469665 @default.
- W2741832760 creator A5041365902 @default.
- W2741832760 creator A5042493483 @default.
- W2741832760 creator A5045419282 @default.
- W2741832760 creator A5046031362 @default.
- W2741832760 creator A5055089158 @default.
- W2741832760 creator A5056540580 @default.
- W2741832760 creator A5064130641 @default.
- W2741832760 creator A5064871109 @default.
- W2741832760 creator A5070650433 @default.
- W2741832760 creator A5083813516 @default.
- W2741832760 date "2017-07-01" @default.
- W2741832760 modified "2023-10-01" @default.
- W2741832760 title "Abstract 2340: Thymidine kinase activity as a response marker for CDK 4/6 inhibition" @default.
- W2741832760 doi "https://doi.org/10.1158/1538-7445.am2017-2340" @default.
- W2741832760 hasPublicationYear "2017" @default.
- W2741832760 type Work @default.
- W2741832760 sameAs 2741832760 @default.
- W2741832760 citedByCount "2" @default.
- W2741832760 countsByYear W27418327602020 @default.
- W2741832760 crossrefType "journal-article" @default.
- W2741832760 hasAuthorship W2741832760A5019319557 @default.
- W2741832760 hasAuthorship W2741832760A5020504047 @default.
- W2741832760 hasAuthorship W2741832760A5036317188 @default.
- W2741832760 hasAuthorship W2741832760A5037469665 @default.
- W2741832760 hasAuthorship W2741832760A5041365902 @default.
- W2741832760 hasAuthorship W2741832760A5042493483 @default.
- W2741832760 hasAuthorship W2741832760A5045419282 @default.
- W2741832760 hasAuthorship W2741832760A5046031362 @default.
- W2741832760 hasAuthorship W2741832760A5055089158 @default.
- W2741832760 hasAuthorship W2741832760A5056540580 @default.
- W2741832760 hasAuthorship W2741832760A5064130641 @default.
- W2741832760 hasAuthorship W2741832760A5064871109 @default.
- W2741832760 hasAuthorship W2741832760A5070650433 @default.
- W2741832760 hasAuthorship W2741832760A5083813516 @default.
- W2741832760 hasConcept C111113717 @default.
- W2741832760 hasConcept C112705442 @default.
- W2741832760 hasConcept C121608353 @default.
- W2741832760 hasConcept C124320809 @default.
- W2741832760 hasConcept C126322002 @default.
- W2741832760 hasConcept C184235292 @default.
- W2741832760 hasConcept C185592680 @default.
- W2741832760 hasConcept C2775930923 @default.
- W2741832760 hasConcept C2779744173 @default.
- W2741832760 hasConcept C2781197716 @default.
- W2741832760 hasConcept C29537977 @default.
- W2741832760 hasConcept C502942594 @default.
- W2741832760 hasConcept C51853150 @default.
- W2741832760 hasConcept C530470458 @default.
- W2741832760 hasConcept C55493867 @default.
- W2741832760 hasConcept C71924100 @default.
- W2741832760 hasConcept C82495950 @default.
- W2741832760 hasConcept C98274493 @default.
- W2741832760 hasConceptScore W2741832760C111113717 @default.
- W2741832760 hasConceptScore W2741832760C112705442 @default.
- W2741832760 hasConceptScore W2741832760C121608353 @default.
- W2741832760 hasConceptScore W2741832760C124320809 @default.
- W2741832760 hasConceptScore W2741832760C126322002 @default.
- W2741832760 hasConceptScore W2741832760C184235292 @default.
- W2741832760 hasConceptScore W2741832760C185592680 @default.
- W2741832760 hasConceptScore W2741832760C2775930923 @default.
- W2741832760 hasConceptScore W2741832760C2779744173 @default.
- W2741832760 hasConceptScore W2741832760C2781197716 @default.
- W2741832760 hasConceptScore W2741832760C29537977 @default.
- W2741832760 hasConceptScore W2741832760C502942594 @default.
- W2741832760 hasConceptScore W2741832760C51853150 @default.
- W2741832760 hasConceptScore W2741832760C530470458 @default.
- W2741832760 hasConceptScore W2741832760C55493867 @default.
- W2741832760 hasConceptScore W2741832760C71924100 @default.
- W2741832760 hasConceptScore W2741832760C82495950 @default.
- W2741832760 hasConceptScore W2741832760C98274493 @default.
- W2741832760 hasIssue "13_Supplement" @default.
- W2741832760 hasLocation W27418327601 @default.
- W2741832760 hasOpenAccess W2741832760 @default.
- W2741832760 hasPrimaryLocation W27418327601 @default.
- W2741832760 hasRelatedWork W1593418262 @default.
- W2741832760 hasRelatedWork W2491062142 @default.
- W2741832760 hasRelatedWork W2529686719 @default.
- W2741832760 hasRelatedWork W2600199136 @default.
- W2741832760 hasRelatedWork W2913043020 @default.
- W2741832760 hasRelatedWork W3030916686 @default.
- W2741832760 hasRelatedWork W3159881570 @default.
- W2741832760 hasRelatedWork W3200026446 @default.
- W2741832760 hasRelatedWork W4243251494 @default.
- W2741832760 hasRelatedWork W4362546411 @default.
- W2741832760 hasVolume "77" @default.
- W2741832760 isParatext "false" @default.
- W2741832760 isRetracted "false" @default.
- W2741832760 magId "2741832760" @default.
- W2741832760 workType "article" @default.