PMID- 32429458 OWN - NLM STAT- MEDLINE DCOM- 20210224 LR - 20210224 IS - 2073-4409 (Electronic) IS - 2073-4409 (Linking) VI - 9 IP - 5 DP - 2020 May 16 TI - Fractionation-Dependent Radiosensitization by Molecular Targeting of Nek1. LID - 10.3390/cells9051235 [doi] LID - 1235 AB - NIMA (never-in-mitosis gene A)-related kinase 1 (Nek1) is shown to impact on different cellular pathways such as DNA repair, checkpoint activation, and apoptosis. Its role as a molecular target for radiation sensitization of malignant cells, however, remains elusive. Stably transduced doxycycline (Dox)-inducible Nek1 shRNA HeLa cervix and siRNA-transfected HCT-15 colorectal carcinoma cells were irradiated in vitro and 3D clonogenic radiation survival, residual DNA damage, cell cycle distribution, and apoptosis were analyzed. Nek1 knockdown (KD) sensitized both cell lines to ionizing radiation following a single dose irradiation and more pronounced in combination with a 6 h fractionation (3 x 2 Gy) regime. For preclinical analyses we focused on cervical cancer. Nek1 shRNA HeLa cells were grafted into NOD/SCID/IL-2Rgammac-/- (NSG) mice and Nek1 KD was induced by Dox-infused drinking water resulting in a significant cytostatic effect if combined with a 6 h fractionation (3 x 2 Gy) regime. In addition, we correlated Nek1 expression in biopsies of patients with cervical cancer with histopathological parameters and clinical follow-up. Our results indicate that elevated levels of Nek1 were associated with an increased rate of local or distant failure, as well as with impaired cancer-specific and overall survival in univariate analyses and for most endpoints in multivariable analyses. Finally, findings from The Cancer Genome Atlas (TCGA) validation cohort confirmed a significant association of high Nek1 expression with a reduced disease-free survival. In conclusion, we consider Nek1 to represent a novel biomarker and potential therapeutic target for drug development in the context of optimized fractionation intervals. FAU - Freund, Isabel AU - Freund I AD - Department of Radiotherapy and Oncology, University Hospital, Goethe University Frankfurt, Theodor-Stern-Kai 7, 60590 Frankfurt am Main, Germany. AD - Radiation Biology and DNA Repair, Technical University of Darmstadt, Schnittspahnstrasse 13, 64287 Darmstadt, Germany. FAU - Hehlgans, Stephanie AU - Hehlgans S AD - Department of Radiotherapy and Oncology, University Hospital, Goethe University Frankfurt, Theodor-Stern-Kai 7, 60590 Frankfurt am Main, Germany. FAU - Martin, Daniel AU - Martin D AD - Department of Radiotherapy and Oncology, University Hospital, Goethe University Frankfurt, Theodor-Stern-Kai 7, 60590 Frankfurt am Main, Germany. FAU - Ensminger, Michael AU - Ensminger M AD - Radiation Biology and DNA Repair, Technical University of Darmstadt, Schnittspahnstrasse 13, 64287 Darmstadt, Germany. FAU - Fokas, Emmanouil AU - Fokas E AD - Department of Radiotherapy and Oncology, University Hospital, Goethe University Frankfurt, Theodor-Stern-Kai 7, 60590 Frankfurt am Main, Germany. AD - Frankfurt Cancer Institute (FCI), Theodor-Stern-Kai 7, Goethe University Frankfurt am Main, 60590 Frankfurt am Main, Germany. AD - German Cancer Research Center (DKFZ), ImNeuenheimer Feld 280, 69120 Heidelberg, Germany. AD - German Cancer Consortium (DKTK) partner site: Frankfurt, 60590 Frankfurt am Main, Germany. FAU - Rodel, Claus AU - Rodel C AD - Department of Radiotherapy and Oncology, University Hospital, Goethe University Frankfurt, Theodor-Stern-Kai 7, 60590 Frankfurt am Main, Germany. AD - Frankfurt Cancer Institute (FCI), Theodor-Stern-Kai 7, Goethe University Frankfurt am Main, 60590 Frankfurt am Main, Germany. AD - German Cancer Research Center (DKFZ), ImNeuenheimer Feld 280, 69120 Heidelberg, Germany. AD - German Cancer Consortium (DKTK) partner site: Frankfurt, 60590 Frankfurt am Main, Germany. FAU - Lobrich, Markus AU - Lobrich M AD - Radiation Biology and DNA Repair, Technical University of Darmstadt, Schnittspahnstrasse 13, 64287 Darmstadt, Germany. FAU - Rodel, Franz AU - Rodel F AD - Department of Radiotherapy and Oncology, University Hospital, Goethe University Frankfurt, Theodor-Stern-Kai 7, 60590 Frankfurt am Main, Germany. AD - Frankfurt Cancer Institute (FCI), Theodor-Stern-Kai 7, Goethe University Frankfurt am Main, 60590 Frankfurt am Main, Germany. AD - German Cancer Research Center (DKFZ), ImNeuenheimer Feld 280, 69120 Heidelberg, Germany. AD - German Cancer Consortium (DKTK) partner site: Frankfurt, 60590 Frankfurt am Main, Germany. LA - eng PT - Journal Article PT - Research Support, Non-U.S. Gov't DEP - 20200516 PL - Switzerland TA - Cells JT - Cells JID - 101600052 RN - 0 (H2AX protein, human) RN - 0 (Histones) RN - EC 2.7.11.1 (NIMA-Related Kinase 1) SB - IM MH - Animals MH - Cell Fractionation/*methods MH - Cell Survival MH - Clone Cells MH - HeLa Cells MH - Histones/metabolism MH - Humans MH - Mice, Inbred NOD MH - Mice, SCID MH - *Molecular Targeted Therapy MH - Multivariate Analysis MH - NIMA-Related Kinase 1/*metabolism MH - Prognosis MH - *Radiation Tolerance MH - Treatment Outcome PMC - PMC7291120 OTO - NOTNLM OT - Nek1 OT - cervical cancer OT - colorectal cancer OT - fractionation OT - prognostic marker OT - radiosensitization OT - xenograft COIS- The authors declare no conflict of interest. The funders had no role in the design of the study, in the collection, analyses, or interpretation of data, in the writing of the manuscript, and in the decision to publish the results. EDAT- 2020/05/21 06:00 MHDA- 2021/02/25 06:00 PMCR- 2020/05/01 CRDT- 2020/05/21 06:00 PHST- 2020/04/24 00:00 [received] PHST- 2020/05/14 00:00 [revised] PHST- 2020/05/15 00:00 [accepted] PHST- 2020/05/21 06:00 [entrez] PHST- 2020/05/21 06:00 [pubmed] PHST- 2021/02/25 06:00 [medline] PHST- 2020/05/01 00:00 [pmc-release] AID - cells9051235 [pii] AID - cells-09-01235 [pii] AID - 10.3390/cells9051235 [doi] PST - epublish SO - Cells. 2020 May 16;9(5):1235. doi: 10.3390/cells9051235.