Show simple item record

dc.contributor.authorKoh, Siang-Boon
dc.contributor.authorCourtin, Aurélie
dc.contributor.authorBoyce, Richard J
dc.contributor.authorBoyle, Robert G
dc.contributor.authorRichards, Frances M
dc.contributor.authorJodrell, Duncan I
dc.date.accessioned2015-07-02T14:18:35Z
dc.date.available2015-07-02T14:18:35Z
dc.date.issued2015-09-01
dc.identifier.citationCancer Research 2015, 75(17), 3583-3595. doi: 10.1158/0008-5472.CAN-14-3347
dc.identifier.issn0008-5472
dc.identifier.urihttps://www.repository.cam.ac.uk/handle/1810/248827
dc.description.abstractCombining cell-cycle checkpoint kinase inhibitors with the DNA-damaging chemotherapeutic agent gemcitabine offers clinical appeal, with a mechanistic rationale based chiefly on abrogation of gemcitabine-induced G2-M checkpoint activation. However, evidence supporting this mechanistic rationale from chemosensitization studies has not been consistent. Here we report a systematic definition of how pancreatic cancer cells harboring mutant p53 respond to this combination therapy, by combining mathematical models with large-scale quantitative biologic analyses of single cells and cell populations. Notably, we uncovered a dynamic range of mechanistic effects at different ratios of gemcitabine and CHK1 inhibitors. Remarkably, effective synergy was attained even where cells exhibited an apparently functional G2-M surveillance mechanism, as exemplified by a lack of both overt premature CDK1 activation and S-phase mitotic entry. Consistent with these findings, S-G2 duration was extended in treated cells, leading to a definable set of lineage-dependent catastrophic fates. At synergistic drug concentrations, global replication stress was a distinct indicator of chemosensitization as characterized molecularly by an accumulation of S-phase cells with high levels of hyperphosphorylated RPA-loaded single-stranded DNA. In a fraction of these cells, persistent genomic damage was observed, including chromosomal fragmentation with a loss of centromeric regions that prevented proper kinetochore-microtubule attachment. Together, our results suggested a "foot-in-the-door" mechanism for drug synergy where cells were destroyed not by frank G2-M phase abrogation but rather by initiating a cumulative genotoxicity that deregulated DNA synthesis.
dc.description.sponsorshipThis study was funded by Cancer Research UK via Institute Senior Group Leader funding (C14303/A17197) to DI Jodrell, and by Sentinel Oncology through an award from Innovate UK.
dc.languageEnglish
dc.language.isoen
dc.publisherAmerican Association for Cancer Research (AACR)
dc.subjectCHK1
dc.subjectgemcitabine
dc.subjectsynergy
dc.subjectcell cycle checkpoint
dc.subjectDNA damage response
dc.titleCHK1 Inhibition Synergizes with Gemcitabine Initially by Destabilizing the DNA Replication Apparatus.
dc.typeArticle
dc.description.versionThis is the author accepted manuscript. The final version is available from American Association for Cancer Research via http://dx.doi.org/10.1158/0008-5472.CAN-14-3347
prism.endingPage3595
prism.publicationDate2015
prism.publicationNameCancer Res
prism.startingPage3583
prism.volume75
dc.rioxxterms.funderCRUK
dc.rioxxterms.projectidC14303/A17197
dcterms.dateAccepted2015-06-01
rioxxterms.versionofrecord10.1158/0008-5472.CAN-14-3347
rioxxterms.licenseref.urihttp://www.rioxx.net/licenses/all-rights-reserved
rioxxterms.licenseref.startdate2015-09-01
dc.contributor.orcidRichards, Fran [0000-0001-7947-7853]
dc.contributor.orcidJodrell, Duncan [0000-0001-9360-1670]
dc.identifier.eissn1538-7445
rioxxterms.typeJournal Article/Review
pubs.funder-project-idCancer Research UK (CB4270)
cam.issuedOnline2015-07-03
rioxxterms.freetoread.startdate2016-09-01


Files in this item

Thumbnail

This item appears in the following Collection(s)

Show simple item record