1
|
Chang L, Huang J, Wang K, Li J, Yan R, Zhu L, Ye J, Wu X, Zhuang S, Li D, Zhang G. Targeting Rad50 sensitizes human nasopharyngeal carcinoma cells to radiotherapy. BMC Cancer 2016; 16:190. [PMID: 26951044 PMCID: PMC4782334 DOI: 10.1186/s12885-016-2190-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Accepted: 02/16/2016] [Indexed: 11/25/2022] Open
Abstract
BACKGROUND The Mre11-Rad50-Nbs1 (MRN) complex is well known for its crucial role in initiating DNA double strand breaks (DSBs) repair pathways to resistant irradiation (IR) injury and thus facilitating radioresistance which severely reduces radiocurability of nasopharyngeal cancer (NPC). Targeting native cellular MRN function would sensitize NPC cells to IR. METHODS A recombinant adenovirus containing a mutant Rad50 gene (Ad-RAD50) expressing Rad50 zinc hook domain but lacking the ATPase domain and the Mre11 interaction domain was constructed to disrupt native cellular MRN functions. The effects of Ad-RAD50 on the MRN functions were assessed in NPC cells lines using western blot, co-immunoprecipitation and confocal microscopy analyses. The increased radiosensitivity of transient Ad-RAD50 to IR was examined in NPC cells, including MTT assay, colony formation. The molecular mechanisms of radiosensitization were confirmed by neutral comet assay and western bolts. Nude mice subcutaneous injection, tumor growth curve and TUNEL assay were used to evaluate tumor regression and apoptosis in vivo. RESULTS Rad50 is remarkably upregulated in NPC cells after IR, implying the critical role of Rad50 in MRN functions. The transient expression of this mutant Rad50 decreased the levels of native cellular Rad50, Mre11 and Nbs1, weakened the interactions among these proteins, abrogated the G2/M arrest induced by DSBs and reduced the DNA repair ability in NPC cells. A combination of IR and mutant RAD50 therapy produced significant tumor cytotoxicity in vitro, with a corresponding increase in DNA damage, prevented proliferation and cell viability. Furthermore, Ad-RAD50 sensitized NPC cells to IR by causing dramatic tumor regression and inducing apoptosis in vivo. CONCLUSION Our findings define a novel therapeutic approach to NPC radiosensitization via targeted native cellular Rad50 disruption.
Collapse
Affiliation(s)
- Lihong Chang
- Department of Otolaryngology-Head & Neck Surgery, The Third Affiliated Hospital, Sun Yat-sen University, NO.600 Tianhe Road, Guangzhou, 510630, China.
| | - Jiancong Huang
- Department of Otolaryngology-Head & Neck Surgery, The Third Affiliated Hospital, Sun Yat-sen University, NO.600 Tianhe Road, Guangzhou, 510630, China.
| | - Kai Wang
- Department of Otolaryngology-Head & Neck Surgery, The Third Affiliated Hospital, Sun Yat-sen University, NO.600 Tianhe Road, Guangzhou, 510630, China.
- Department of Otorhinolaryngology-Head & Neck Surgery, The First People's Hospital of Foshan, Cancheng District, NO.81 Lingnan Bei Road, Foshan, 528000, China.
| | - Jingjia Li
- Department of Otolaryngology-Head & Neck Surgery, The Third Affiliated Hospital, Sun Yat-sen University, NO.600 Tianhe Road, Guangzhou, 510630, China.
| | - Ruicheng Yan
- Department of Otolaryngology-Head & Neck Surgery, The Third Affiliated Hospital, Sun Yat-sen University, NO.600 Tianhe Road, Guangzhou, 510630, China.
- Department of Otolaryngology-Head & Neck Surgery, Zengcheng District People's Hospital of Guangzhou (Boji-Affiliated Hospital of Sun Yat-sen University), Zengcheng District, NO.1 Guangming Dong Road, Guangzhou, 511300, China.
| | - Ling Zhu
- Department of Otolaryngology-Head & Neck Surgery, The Third Affiliated Hospital, Sun Yat-sen University, NO.600 Tianhe Road, Guangzhou, 510630, China.
- Department of Otolaryngology-Head & Neck Surgery, Nanhai Maternity and Child Healthcare Hospital, Nanhai District, NO.6 Guiping Xi Road, Foshan, 528000, China.
| | - Jin Ye
- Department of Otolaryngology-Head & Neck Surgery, The Third Affiliated Hospital, Sun Yat-sen University, NO.600 Tianhe Road, Guangzhou, 510630, China.
| | - Xifu Wu
- Department of Otolaryngology-Head & Neck Surgery, The Third Affiliated Hospital, Sun Yat-sen University, NO.600 Tianhe Road, Guangzhou, 510630, China.
| | - Shimin Zhuang
- Department of Otolaryngology-Head & Neck Surgery, The Third Affiliated Hospital, Sun Yat-sen University, NO.600 Tianhe Road, Guangzhou, 510630, China.
- Department of Otolaryngology-Head & Neck Surgery, The Sixth Affiliated Hospital of Sun Yat-sen University, NO.26 Yuancun Erheng Road, Guangzhou, 510655, China.
| | - Daqing Li
- Department of Otorhinolaryngology-Head & Neck Surgery, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA.
| | - Gehua Zhang
- Department of Otolaryngology-Head & Neck Surgery, The Third Affiliated Hospital, Sun Yat-sen University, NO.600 Tianhe Road, Guangzhou, 510630, China.
| |
Collapse
|
2
|
Oplustilova L, Wolanin K, Mistrik M, Korinkova G, Simkova D, Bouchal J, Lenobel R, Bartkova J, Lau A, O’Connor MJ, Lukas J, Bartek J. Evaluation of candidate biomarkers to predict cancer cell sensitivity or resistance to PARP-1 inhibitor treatment. Cell Cycle 2012; 11:3837-50. [PMID: 22983061 PMCID: PMC3495826 DOI: 10.4161/cc.22026] [Citation(s) in RCA: 123] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Impaired DNA damage response pathways may create vulnerabilities of cancer cells that can be exploited therapeutically. One such selective vulnerability is the sensitivity of BRCA1- or BRCA2-defective tumors (hence defective in DNA repair by homologous recombination, HR) to inhibitors of the poly(ADP-ribose) polymerase-1 (PARP-1), an enzyme critical for repair pathways alternative to HR. While promising, treatment with PARP-1 inhibitors (PARP-1i) faces some hurdles, including (1) acquired resistance, (2) search for other sensitizing, non-BRCA1/2 cancer defects and (3) lack of biomarkers to predict response to PARP-1i. Here we addressed these issues using PARP-1i on 20 human cell lines from carcinomas of the breast, prostate, colon, pancreas and ovary. Aberrations of the Mre11-Rad50-Nbs1 (MRN) complex sensitized cancer cells to PARP-1i, while p53 status was less predictive, even in response to PARP-1i combinations with camptothecin or ionizing radiation. Furthermore, monitoring PARsylation and Rad51 foci formation as surrogate markers for PARP activity and HR, respectively, supported their candidacy for biomarkers of PARP-1i responses. As to resistance mechanisms, we confirmed the role of the multidrug resistance efflux transporters and its reversibility. More importantly, we demonstrated that shRNA lentivirus-mediated depletion of 53BP1 in human BRCA1-mutant breast cancer cells increased their resistance to PARP-1i. Given the preferential loss of 53BP1 in BRCA-defective and triple-negative breast carcinomas, our findings warrant assessment of 53BP1 among candidate predictive biomarkers of response to PARPi. Overall, this study helps characterize genetic and functional determinants of cellular responses to PARP-1i and contributes to the search for biomarkers to exploit PARP inhibitors in cancer therapy.
Collapse
Affiliation(s)
- Lenka Oplustilova
- Danish Cancer Society Research Center; Copenhagen, Denmark
- AstraZeneca; iMed Oncology; Macclesfield, Cheshire, UK
| | - Kamila Wolanin
- Danish Cancer Society Research Center; Copenhagen, Denmark
| | - Martin Mistrik
- Institute of Molecular and Translational Medicine; Faculty of Medicine and Dentistry; Palacky University; Olomouc, Czech Republic
| | - Gabriela Korinkova
- Institute of Molecular and Translational Medicine; Faculty of Medicine and Dentistry; Palacky University; Olomouc, Czech Republic
| | - Dana Simkova
- Institute of Molecular and Translational Medicine; Faculty of Medicine and Dentistry; Palacky University; Olomouc, Czech Republic
| | - Jan Bouchal
- Institute of Molecular and Translational Medicine; Faculty of Medicine and Dentistry; Palacky University; Olomouc, Czech Republic
| | - Rene Lenobel
- Laboratory of Growth Regulators; Palacky University Olomouc; Olomouc, Czech Republic
| | | | - Alan Lau
- AstraZeneca; iMed Oncology; Macclesfield, Cheshire, UK
| | | | - Jiri Lukas
- Danish Cancer Society Research Center; Copenhagen, Denmark
- Novo Nordisk Foundation Center for Protein Research; Faculty of Health and Medical Sciences; University of Copenhagen; Copenhagen, Denmark
| | - Jiri Bartek
- Danish Cancer Society Research Center; Copenhagen, Denmark
- Institute of Molecular and Translational Medicine; Faculty of Medicine and Dentistry; Palacky University; Olomouc, Czech Republic
| |
Collapse
|
3
|
Carson CT, Orazio NI, Lee DV, Suh J, Bekker-Jensen S, Araujo FD, Lakdawala SS, Lilley CE, Bartek J, Lukas J, Weitzman MD. Mislocalization of the MRN complex prevents ATR signaling during adenovirus infection. EMBO J 2009; 28:652-62. [PMID: 19197236 PMCID: PMC2666027 DOI: 10.1038/emboj.2009.15] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2008] [Accepted: 12/23/2008] [Indexed: 01/13/2023] Open
Abstract
The protein kinases ataxia-telangiectasia mutated (ATM) and ATM-Rad3 related (ATR) are activated in response to DNA damage, genotoxic stress and virus infections. Here we show that during infection with wild-type adenovirus, ATR and its cofactors RPA32, ATRIP and TopBP1 accumulate at viral replication centres, but there is minimal ATR activation. We show that the Mre11/Rad50/Nbs1 (MRN) complex is recruited to viral centres only during infection with adenoviruses lacking the early region E4 and ATR signaling is activated. This suggests a novel requirement for the MRN complex in ATR activation during virus infection, which is independent of Mre11 nuclease activity and recruitment of RPA/ATR/ATRIP/TopBP1. Unlike other damage scenarios, we found that ATM and ATR signaling are not dependent on each other during infection. We identify a region of the viral E4orf3 protein responsible for immobilization of the MRN complex and show that this prevents ATR signaling during adenovirus infection. We propose that immobilization of the MRN damage sensor by E4orf3 protein prevents recognition of viral genomes and blocks detrimental aspects of checkpoint signaling during virus infection.
Collapse
Affiliation(s)
- Christian T Carson
- Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, CA, USA
- Graduate Program, Division of Biology, University of California, San Diego, CA, USA
| | - Nicole I Orazio
- Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, CA, USA
- Graduate Program, Division of Biology, University of California, San Diego, CA, USA
| | - Darwin V Lee
- Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, CA, USA
| | - Junghae Suh
- Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, CA, USA
| | - Simon Bekker-Jensen
- Centre for Genotoxic Stress Research, Institute of Cancer Biology, Danish Cancer Society, Copenhagen, Denmark
| | - Felipe D Araujo
- Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, CA, USA
| | - Seema S Lakdawala
- Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, CA, USA
- Graduate Program, Division of Biology, University of California, San Diego, CA, USA
| | - Caroline E Lilley
- Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, CA, USA
| | - Jiri Bartek
- Centre for Genotoxic Stress Research, Institute of Cancer Biology, Danish Cancer Society, Copenhagen, Denmark
| | - Jiri Lukas
- Centre for Genotoxic Stress Research, Institute of Cancer Biology, Danish Cancer Society, Copenhagen, Denmark
| | - Matthew D Weitzman
- Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, CA, USA
| |
Collapse
|
4
|
Abstract
The protein complex including Mre11, Rad50, and Nbs1 (MRN) functions in DNA double-strand break repair to recognize and process DNA ends as well as signal for cell cycle arrest. Amino acid sequence similarity and overall architecture make Rad50 a member of the structural maintenance of chromosome (SMC) protein family. Like SMC proteins, Rad50 function depends on ATP binding and hydrolysis. All current evidence indicates that ATP binding and hydrolysis cause architectural rearrangements in SMC protein complexes that are important for their functions in organizing DNA. In the case of the MRN complex, the functional significance of ATP binding and hydrolysis are not yet defined. Here we review the data on the ATP-dependent activities of MRN and their possible mechanistic significance. We present some speculation on the role of ATP for function of the MRN complex based on the similarities and differences in the molecular architecture of the Rad50-containing complexes and the SMC complexes condensin and cohesin.
Collapse
Affiliation(s)
- Eri Kinoshita
- Department of Cell Biology and Genetics, Erasmus University Medical Center, Box 2040, 3000 CA Rotterdam, The Netherlands
| | - Eddy van der Linden
- Department of Cell Biology and Genetics, Erasmus University Medical Center, Box 2040, 3000 CA Rotterdam, The Netherlands
| | - Humberto Sanchez
- Department of Cell Biology and Genetics, Erasmus University Medical Center, Box 2040, 3000 CA Rotterdam, The Netherlands
| | - Claire Wyman
- Department of Cell Biology and Genetics, Erasmus University Medical Center, Box 2040, 3000 CA Rotterdam, The Netherlands. Department of Radiation Oncology, Erasmus University Medical Center, Box 2040, 3000 CA Rotterdam, The Netherlands. Department of Cell Biology and Genetics, Erasmus MC, PO Box 2040, 3000 DR Rotterdam, The Netherlands
| |
Collapse
|