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Targeting the DNA Damage Response for Radiosensitization. CANCER DRUG DISCOVERY AND DEVELOPMENT 2020. [DOI: 10.1007/978-3-030-49701-9_9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Farago AF, Yeap BY, Stanzione M, Hung YP, Heist RS, Marcoux JP, Zhong J, Rangachari D, Barbie DA, Phat S, Myers DT, Morris R, Kem M, Dubash TD, Kennedy EA, Digumarthy SR, Sequist LV, Hata AN, Maheswaran S, Haber DA, Lawrence MS, Shaw AT, Mino-Kenudson M, Dyson NJ, Drapkin BJ. Combination Olaparib and Temozolomide in Relapsed Small-Cell Lung Cancer. Cancer Discov 2019; 9:1372-1387. [PMID: 31416802 PMCID: PMC7319046 DOI: 10.1158/2159-8290.cd-19-0582] [Citation(s) in RCA: 137] [Impact Index Per Article: 27.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Revised: 07/05/2019] [Accepted: 07/19/2019] [Indexed: 12/12/2022]
Abstract
Small-cell lung cancer (SCLC) is an aggressive malignancy in which inhibitors of PARP have modest single-agent activity. We performed a phase I/II trial of combination olaparib tablets and temozolomide (OT) in patients with previously treated SCLC. We established a recommended phase II dose of olaparib 200 mg orally twice daily with temozolomide 75 mg/m2 daily, both on days 1 to 7 of a 21-day cycle, and expanded to a total of 50 patients. The confirmed overall response rate was 41.7% (20/48 evaluable); median progression-free survival was 4.2 months [95% confidence interval (CI), 2.8-5.7]; and median overall survival was 8.5 months (95% CI, 5.1-11.3). Patient-derived xenografts (PDX) from trial patients recapitulated clinical OT responses, enabling a 32-PDX coclinical trial. This revealed a correlation between low basal expression of inflammatory-response genes and cross-resistance to both OT and standard first-line chemotherapy (etoposide/platinum). These results demonstrate a promising new therapeutic strategy in SCLC and uncover a molecular signature of those tumors most likely to respond. SIGNIFICANCE: We demonstrate substantial clinical activity of combination olaparib/temozolomide in relapsed SCLC, revealing a promising new therapeutic strategy for this highly recalcitrant malignancy. Through an integrated coclinical trial in PDXs, we then identify a molecular signature predictive of response to OT, and describe the common molecular features of cross-resistant SCLC.See related commentary by Pacheco and Byers, p. 1340.This article is highlighted in the In This Issue feature, p. 1325.
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Affiliation(s)
- Anna F Farago
- Massachusetts General Hospital Cancer Center, Boston, Massachusetts.
- Dana-Farber Cancer Center, Boston, Massachusetts
| | - Beow Y Yeap
- Massachusetts General Hospital Cancer Center, Boston, Massachusetts
- Dana-Farber Cancer Center, Boston, Massachusetts
| | | | - Yin P Hung
- Massachusetts General Hospital Cancer Center, Boston, Massachusetts
- Dana-Farber Cancer Center, Boston, Massachusetts
| | - Rebecca S Heist
- Massachusetts General Hospital Cancer Center, Boston, Massachusetts
- Dana-Farber Cancer Center, Boston, Massachusetts
| | - J Paul Marcoux
- Dana-Farber Cancer Center, Boston, Massachusetts
- Beth Israel Deaconess Medical Center, Boston, Massachusetts
| | - Jun Zhong
- Massachusetts General Hospital Cancer Center, Boston, Massachusetts
| | - Deepa Rangachari
- Dana-Farber Cancer Center, Boston, Massachusetts
- Department of Radiology, Massachusetts General Hospital, Boston, Massachusetts
| | - David A Barbie
- Dana-Farber Cancer Center, Boston, Massachusetts
- Beth Israel Deaconess Medical Center, Boston, Massachusetts
| | - Sarah Phat
- Massachusetts General Hospital Cancer Center, Boston, Massachusetts
| | - David T Myers
- Massachusetts General Hospital Cancer Center, Boston, Massachusetts
| | - Robert Morris
- Massachusetts General Hospital Cancer Center, Boston, Massachusetts
| | - Marina Kem
- Massachusetts General Hospital Cancer Center, Boston, Massachusetts
| | | | | | - Subba R Digumarthy
- Dana-Farber Cancer Center, Boston, Massachusetts
- Howard Hughes Medical Institute, Bethesda, Maryland
| | - Lecia V Sequist
- Massachusetts General Hospital Cancer Center, Boston, Massachusetts
- Dana-Farber Cancer Center, Boston, Massachusetts
| | - Aaron N Hata
- Massachusetts General Hospital Cancer Center, Boston, Massachusetts
- Dana-Farber Cancer Center, Boston, Massachusetts
| | - Shyamala Maheswaran
- Massachusetts General Hospital Cancer Center, Boston, Massachusetts
- Dana-Farber Cancer Center, Boston, Massachusetts
| | - Daniel A Haber
- Massachusetts General Hospital Cancer Center, Boston, Massachusetts
- Dana-Farber Cancer Center, Boston, Massachusetts
- Harvard Medical School, Boston, Massachusetts
| | - Michael S Lawrence
- Massachusetts General Hospital Cancer Center, Boston, Massachusetts
- Dana-Farber Cancer Center, Boston, Massachusetts
| | - Alice T Shaw
- Massachusetts General Hospital Cancer Center, Boston, Massachusetts
- Dana-Farber Cancer Center, Boston, Massachusetts
| | - Mari Mino-Kenudson
- Massachusetts General Hospital Cancer Center, Boston, Massachusetts
- Dana-Farber Cancer Center, Boston, Massachusetts
| | - Nicholas J Dyson
- Massachusetts General Hospital Cancer Center, Boston, Massachusetts
- Dana-Farber Cancer Center, Boston, Massachusetts
| | - Benjamin J Drapkin
- Massachusetts General Hospital Cancer Center, Boston, Massachusetts.
- Dana-Farber Cancer Center, Boston, Massachusetts
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Lee TW, Wong WW, Dickson BD, Lipert B, Cheng GJ, Hunter FW, Hay MP, Wilson WR. Radiosensitization of head and neck squamous cell carcinoma lines by DNA-PK inhibitors is more effective than PARP-1 inhibition and is enhanced by SLFN11 and hypoxia. Int J Radiat Biol 2019; 95:1597-1612. [PMID: 31490091 DOI: 10.1080/09553002.2019.1664787] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Background and purpose: Poly(ADP-ribose)polymerase-1 (PARP1) and DNA-dependent protein kinase (DNA-PK) play key roles in the repair of radiation-induced DNA double strand breaks, but it is unclear which is the preferred therapeutic target in radiotherapy. Here we compare small molecule inhibitors of both as radiosensitizers of head and neck squamous cell carcinoma (HNSCC) cell lines.Methods: Two PARP1 inhibitors (olaparib, veliparib) and two DNA-PK inhibitors (KU57788, IC87361) were tested in 14 HNSCC cell lines and two non-tumorigenic lines (HEK-293 and WI-38/Va-13), with drug exposure for 6 or 24 h post-irradiation, using regrowth assays. For three lines (UT-SCC-54C, -74B, -76B), radiosensitization was also assessed by clonogenic assay under oxia and acute (6 h) anoxia, and for 54C cells under chronic hypoxia (0.2% O2 for 48 h). Relationships between sensitizer enhancement ratios (SER) and gene expression, assessed by RNA sequencing, were evaluated.Results: The inhibitors were minimally cytotoxic in the absence of radiation, with 74B and 54C cells the most sensitive to both olaparib and KU57788. Median SER values for each inhibitor at 1.1 µM were 1.12 (range 1.02-1.24) for olaparib, 1.08 (1.04-1.13) for veliparib, 1.35 (1.10-1.64) for IC87361 and 1.77 (1.41-2.38) for KU57788. The higher SER values for the DNA-PK inhibitors were observed with all cell lines (except HEK-293) and all concentrations tested and were confirmed by clonogenic assay. Radiosensitization by the DNA-PK inhibitors correlated with expression of SLFN11 mRNA. Radiosensitization by IC87361 and olaparib was significantly enhanced under acute anoxia and chronic hypoxia.Conclusions: The DNA-PK inhibitors KU57788 and IC87361 are more effective radiosensitizers than the PARP-1 inhibitors olaparib and veliparib at non-cytotoxic concentrations in HNSCC cell cultures and their activity is enhanced by SLFN11 and hypoxia.
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Affiliation(s)
- Tet Woo Lee
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand.,Maurice Wilkins Centre for Molecular Biodiscovery, Auckland, New Zealand
| | - Way Wua Wong
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand
| | - Benjamin D Dickson
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand
| | - Barbara Lipert
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand
| | - Gary J Cheng
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand
| | - Francis W Hunter
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand.,Maurice Wilkins Centre for Molecular Biodiscovery, Auckland, New Zealand
| | - Michael P Hay
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand.,Maurice Wilkins Centre for Molecular Biodiscovery, Auckland, New Zealand
| | - William R Wilson
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand.,Maurice Wilkins Centre for Molecular Biodiscovery, Auckland, New Zealand
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Targeting DNA Replication Stress and DNA Double-Strand Break Repair for Optimizing SCLC Treatment. Cancers (Basel) 2019; 11:cancers11091289. [PMID: 31480716 PMCID: PMC6770306 DOI: 10.3390/cancers11091289] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2019] [Revised: 08/22/2019] [Accepted: 08/27/2019] [Indexed: 12/12/2022] Open
Abstract
Small cell lung cancer (SCLC), accounting for about 15% of all cases of lung cancer worldwide, is the most lethal form of lung cancer. Despite an initially high response rate of SCLC to standard treatment, almost all patients are invariably relapsed within one year. Effective therapeutic strategies are urgently needed to improve clinical outcomes. Replication stress is a hallmark of SCLC due to several intrinsic factors. As a consequence, constitutive activation of the replication stress response (RSR) pathway and DNA damage repair system is involved in counteracting this genotoxic stress. Therefore, therapeutic targeting of such RSR and DNA damage repair pathways will be likely to kill SCLC cells preferentially and may be exploited in improving chemotherapeutic efficiency through interfering with DNA replication to exert their functions. Here, we summarize potentially valuable targets involved in the RSR and DNA damage repair pathways, rationales for targeting them in SCLC treatment and ongoing clinical trials, as well as possible predictive biomarkers for patient selection in the management of SCLC.
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Pilié PG, Gay CM, Byers LA, O'Connor MJ, Yap TA. PARP Inhibitors: Extending Benefit Beyond BRCA-Mutant Cancers. Clin Cancer Res 2019; 25:3759-3771. [PMID: 30760478 DOI: 10.1158/1078-0432.ccr-18-0968] [Citation(s) in RCA: 225] [Impact Index Per Article: 45.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Revised: 01/04/2019] [Accepted: 02/08/2019] [Indexed: 02/03/2023]
Abstract
A mounting body of evidence now indicates that PARP inhibitors have the potential to be used as a foundation for both monotherapy and combination strategies across a wide spectrum of molecular backgrounds and tumor types. Although PARP inhibitors as a class display many similarities, critical differences in structure can translate into differences in tolerability and antitumor activity that have important implications for the clinic. Furthermore, while PARP inhibitors have demonstrated a clear role in treating tumors with underlying homologous recombination deficiencies, there is now biological and early clinical evidence to support their use in other molecular subsets of cancer, including tumors associated with high levels of replication stress such as small-cell lung cancer. In this article, we highlight the key similarities and differences between individual PARP inhibitors and their implications for the clinic. We discuss data that currently support clinical strategies for extending the benefit of PARP inhibitors beyond BRCA-mutant cancers, toward broader populations of patients through the use of novel biomarkers of homologous recombination repair deficiency (HRD), as well as predictive biomarkers rooted in mechanisms of sensitivity outside of HRD. We also explore the potential application of PARP inhibitors in earlier treatment settings, including neoadjuvant, adjuvant, and even chemoprevention approaches. Finally, we focus on promising combination therapeutic strategies, such as those with other DNA damage response (DDR) inhibitors such as ATR inhibitors, immune checkpoint inhibitors, and non-DDR-targeted agents that induce "chemical BRCAness."
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Affiliation(s)
- Patrick G Pilié
- Department of Genitourinary Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Carl M Gay
- Department of Thoracic/Head and Neck Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Lauren A Byers
- Department of Thoracic/Head and Neck Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Mark J O'Connor
- Oncology Innovative Medicines and Early Clinical Development, AstraZeneca, Cambridge, United Kingdom
| | - Timothy A Yap
- Department of Thoracic/Head and Neck Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas.
- Khalifa Institute for Personalized Cancer Therapy, The University of Texas MD Anderson Cancer Center, Houston, Texas
- Department of Investigational Cancer Therapeutics (Phase I Program), The University of Texas MD Anderson Cancer Center, Houston, Texas
- The Institute for Applied Cancer Science, The University of Texas MD Anderson Cancer Center, Houston, Texas
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Laird J, Lok BH, Carney B, Kossatz S, de Stanchina E, Reiner T, Poirier JT, Rudin CM. Positron-Emission Tomographic Imaging of a Fluorine 18-Radiolabeled Poly(ADP-Ribose) Polymerase 1 Inhibitor Monitors the Therapeutic Efficacy of Talazoparib in SCLC Patient-Derived Xenografts. J Thorac Oncol 2019; 14:1743-1752. [PMID: 31195178 DOI: 10.1016/j.jtho.2019.05.032] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Revised: 05/15/2019] [Accepted: 05/29/2019] [Indexed: 01/04/2023]
Abstract
INTRODUCTION Inhibitors of poly-(ADP)-ribose polymerase (PARP) are promising therapeutics for SCLC. We tested whether PARP inhibitor (PARPi) target engagement as measured by a fluorine 18-radiolabeled PARPi ([18F]PARPi) has the potential to predict drug efficacy in vivo. METHODS Tumor growth inhibition during daily talazoparib treatment was evaluated in mice engrafted with SCLC patient-derived xenografts to evaluate talazoparib efficacy at multiple doses. Mice were intravenously injected with [18F]PARPi radiotracer at multiple timepoints after single doses of oral talazoparib to quantitatively assess the extent to which talazoparib could reduce tumor radiotracer uptake and positron-emission tomographic (PET)/computer tomographic activity. Tumors were harvested and tumor poly-(ADP) ribose level was measured by enzyme-linked immunosorbent assay. RESULTS A dose range of talazoparib with differential therapeutic efficacy was established, with significant delay in time to reach 1000 mm3 for tumors treated with 0.3 mg/kg (p = 0.02) but not 0.1 mg/kg talazoparib. On PET/computed tomography with [18F]PARPi, reduction in [18F]PARPi uptake after talazoparib dosing was consistent with talazoparib clearance, with reduction in PET activity attenuating over 24 hours. Talazoparib target engagement, measured by maximum tumor PET uptake, increased in a dose-dependent manner (3.9% versus 2.1% injected dose/g for 0.1 and 0.3 mg/kg at 3 hours post-talazoparib, p = 0.003) and correlated with PARP enzymatic activity among individual tumors as measured by total tumor poly-(ADP) ribose (p = 0.04, R = 0.62 at 1 hour post-talazoparib). CONCLUSIONS PET imaging using [18F]PARPi has the potential to be a powerful tool in treatment monitoring by assessing PARPi target engagement in real-time.
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Affiliation(s)
- James Laird
- Molecular Pharmacology Program and Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, New York; New York University School of Medicine, New York, New York
| | - Benjamin H Lok
- Molecular Pharmacology Program and Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, New York; Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Brandon Carney
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York; Department of Chemistry, Hunter College and PhD Program in Chemistry, The Graduate Center of the City University of New York, New York, New York
| | - Susanne Kossatz
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Elisa de Stanchina
- Antitumor Assessment Core Facility, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Thomas Reiner
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York; Department of Radiology, Weill Cornell Medical College, New York, New York; Chemical Biology Program, Memorial Sloan Kettering Cancer Center, New York, New York
| | - John T Poirier
- Molecular Pharmacology Program and Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Charles M Rudin
- Molecular Pharmacology Program and Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, New York; Department of Medicine, Weill Cornell Medical College, New York, New York.
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DuRoss AN, Neufeld MJ, Landry MR, Rosch JG, Eaton CT, Sahay G, Thomas CR, Sun C. Micellar Formulation of Talazoparib and Buparlisib for Enhanced DNA Damage in Breast Cancer Chemoradiotherapy. ACS APPLIED MATERIALS & INTERFACES 2019; 11:12342-12356. [PMID: 30860347 PMCID: PMC7213279 DOI: 10.1021/acsami.9b02408] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Chemoradiation is an effective combined modality therapeutic approach that utilizes principles of spatial cooperation to combat the adaptability associated with cancer and to potentially expand the therapeutic window. Optimal therapeutic efficacy requires intelligent selection and refinement of radiosynergistic pharmaceutical agents, enhanced delivery methods, and temporal consideration. Here, a monodisperse sub-20 nm mixed poloxamer micelle (MPM) system was developed to deliver hydrophobic drugs intravenously, in tandem with ionizing radiation. This report demonstrates in vitro synergy and enhanced radiosensitivity when two molecularly targeted DNA repair inhibitors, talazoparib and buparlisib, are encapsulated and combined with radiation in a 4T1 murine breast cancer model. Evaluation of in vivo biodistribution and toxicity exhibited no reduction in particle accumulation upon radiation and a lack of both acute and chronic toxicities. In vivo efficacy studies suggested the promise of combining talazoparib, buparlisib, and radiation to enhance survival and control tumor growth. Tissue analysis suggests enhanced DNA damage leading to apoptosis, thus increasing efficacy. These findings highlight the challenges associated with utilizing clinically relevant inclusion criteria and treatment protocols because complete tumor regression and extended survival were masked by an aggressively metastasizing model. As with clinical treatment regimens, the findings here establish a need for further optimization of this multimodal platform.
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Affiliation(s)
- Allison N. DuRoss
- Department of Pharmaceutical Sciences, College of Pharmacy, Oregon State University, Portland, OR 97201, USA
| | - Megan J. Neufeld
- Department of Pharmaceutical Sciences, College of Pharmacy, Oregon State University, Portland, OR 97201, USA
| | - Madeleine R. Landry
- Department of Pharmaceutical Sciences, College of Pharmacy, Oregon State University, Portland, OR 97201, USA
| | - Justin G. Rosch
- Department of Pharmaceutical Sciences, College of Pharmacy, Oregon State University, Portland, OR 97201, USA
| | - Colin T. Eaton
- Department of Pharmaceutical Sciences, College of Pharmacy, Oregon State University, Portland, OR 97201, USA
| | - Gaurav Sahay
- Department of Pharmaceutical Sciences, College of Pharmacy, Oregon State University, Portland, OR 97201, USA
- Department of Biomedical Engineering, School of Medicine, Oregon Health & Science University, Portland, OR 97201, USA
| | - Charles R. Thomas
- Department of Radiation Medicine, School of Medicine, Oregon Health & Science University, Portland, OR 97239, USA
| | - Conroy Sun
- Department of Pharmaceutical Sciences, College of Pharmacy, Oregon State University, Portland, OR 97201, USA
- Department of Radiation Medicine, School of Medicine, Oregon Health & Science University, Portland, OR 97239, USA
- Corresponding author: (C. Sun)
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Zhang S, Chao HH, Wang X, Zhang Z, Lee EYC, Lee MYWT. Loss of the p12 subunit of DNA polymerase delta leads to a defect in HR and sensitization to PARP inhibitors. DNA Repair (Amst) 2019; 73:64-70. [PMID: 30470508 PMCID: PMC6312503 DOI: 10.1016/j.dnarep.2018.11.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Revised: 11/08/2018] [Accepted: 11/08/2018] [Indexed: 01/07/2023]
Abstract
Human DNA polymerase δ is normally present in unstressed, non-dividing cells as a heterotetramer (Pol δ4). Its smallest subunit, p12, is transiently degraded in response to UV damage, as well as during the entry into S-phase, resulting in the conversion of Pol δ4 to a trimer (Pol δ3). In order to further understand the specific cellular roles of these two forms of Pol δ, the gene (POLD4) encoding p12 was disrupted by CRISPR/Cas9 to produce p12 knockout (p12KO) cells. Thus, Pol δ4 is absent in p12KO cells, leaving Pol δ3 as the sole source of Pol δ activity. GFP reporter assays revealed that the p12KO cells exhibited a defect in homologous recombination (HR) repair, indicating that Pol δ4, but not Pol δ3, is required for HR. Expression of Flag-tagged p12 in p12KO cells to restore Pol δ4 alleviated the HR defect. These results establish a specific requirement for Pol δ4 in HR repair. This leads to the prediction that p12KO cells should be more sensitive to chemotherapeutic agents, and should exhibit synthetic lethal killing by PARP inhibitors. These predictions were confirmed by clonogenic cell survival assays of p12KO cells treated with cisplatin and mitomycin C, and with the PARP inhibitors Olaparib, Talazoparib, Rucaparib, and Niraparib. The sensitivity to PARP inhibitors in H1299-p12KO cells was alleviated by expression of Flag-p12. These findings have clinical significance, as the expression levels of p12 could be a predictive biomarker of tumor response to PARP inhibitors. In addition, small cell lung cancers (SCLC) are known to exhibit a defect in p12 expression. Analysis of several SCLC cell lines showed that they exhibit hypersensitivity to PARP inhibitors, providing evidence that loss of p12 expression could represent a novel molecular basis for HR deficiency.
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Affiliation(s)
- Sufang Zhang
- Department of Biochemistry and Molecular Biology, New York Medical College, Valhalla, NY 10595, United States
| | - Hsiao Hsiang Chao
- Department of Biochemistry and Molecular Biology, New York Medical College, Valhalla, NY 10595, United States
| | - Xiaoxiao Wang
- Department of Biochemistry and Molecular Biology, New York Medical College, Valhalla, NY 10595, United States
| | - Zhongtao Zhang
- Department of Biochemistry and Molecular Biology, New York Medical College, Valhalla, NY 10595, United States
| | - Ernest Y C Lee
- Department of Biochemistry and Molecular Biology, New York Medical College, Valhalla, NY 10595, United States
| | - Marietta Y W T Lee
- Department of Biochemistry and Molecular Biology, New York Medical College, Valhalla, NY 10595, United States.
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