A. A. Goodarzi and P. A. Jeggo, The Repair and Signaling Responses to DNA Double-Strand Breaks, Adv Genet, vol.82, pp.1-45, 2013.
DOI : 10.1016/B978-0-12-407676-1.00001-9

L. Woodbine, A. R. Gennery, and P. A. Jeggo, The clinical impact of deficiency in DNA non-homologous end-joining, DNA Repair, vol.16, pp.84-96, 2014.
DOI : 10.1016/j.dnarep.2014.02.011

A. Ciccia and S. J. Elledge, The DNA Damage Response: Making It Safe to Play with Knives, Molecular Cell, vol.40, issue.2, pp.179-204, 2010.
DOI : 10.1016/j.molcel.2010.09.019

C. Jekimovs, Chemotherapeutic Compounds Targeting the DNA Double-Strand Break Repair Pathways: The Good, the Bad, and the Promising, Frontiers in Oncology, vol.110, issue.2, p.86, 2014.
DOI : 10.1073/pnas.1303800110

M. R. Lieber, The Mechanism of Double-Strand DNA Break Repair by the Nonhomologous DNA End-Joining Pathway, Annual Review of Biochemistry, vol.79, issue.1, pp.181-211, 2010.
DOI : 10.1146/annurev.biochem.052308.093131

K. K. Chiruvella, Z. Liang, and T. Wilson, Repair of Double-Strand Breaks by End Joining, Cold Spring Harbor Perspectives in Biology, vol.5, issue.5, p.12757, 2013.
DOI : 10.1101/cshperspect.a012757

S. K. Radhakrishnan, N. Jette, and S. P. Lees-miller, Non-homologous end joining: Emerging themes and unanswered questions, DNA Repair, vol.17, pp.2-8, 2014.
DOI : 10.1016/j.dnarep.2014.01.009

URL : http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4084493

C. A. Waters, N. T. Strande, D. W. Wyatt, J. M. Pryor, and D. A. Ramsden, Nonhomologous end joining: A good solution for bad ends, DNA Repair, vol.17, pp.39-51, 2014.
DOI : 10.1016/j.dnarep.2014.02.008

S. E. Critchlow, R. P. Bowater, and S. P. Jackson, Mammalian DNA double-strand break repair protein XRCC4 interacts with DNA ligase IV, Current Biology, vol.7, issue.8, pp.588-598, 1997.
DOI : 10.1016/S0960-9822(06)00258-2

URL : http://doi.org/10.1016/s0960-9822(06)00258-2

U. Grawunder, Activity of DNA ligase IV stimulated by complex formation with XRCC4 protein in mammalian cells, Nature, vol.388, pp.492-495, 1997.

M. Modesti, J. E. Hesse, and M. Gellert, DNA binding of Xrcc4 protein is associated with V(D)Jrecombination but not with stimulation of DNA ligase IV activity, The EMBO Journal, vol.18, issue.7, pp.2008-2018, 1999.
DOI : 10.1093/emboj/18.7.2008

M. Bryans, M. C. Valenzano, and T. D. Stamato, Absence of DNA ligase IV protein in XR-1 cells: evidence for stabilization by XRCC4, Mutation Research/DNA Repair, vol.433, issue.1, pp.53-58, 1999.
DOI : 10.1016/S0921-8777(98)00063-9

D. Davidson, L. Amrein, L. Panasci, and R. Aloyz, Small Molecules, Inhibitors of DNA-PK, Targeting DNA Repair, and Beyond, Frontiers in Pharmacology, vol.4, p.5, 2013.
DOI : 10.3389/fphar.2013.00005

D. A. Chistiakov, N. V. Voronova, and A. Chistiakov, Ligase IV syndrome, Ligase IV syndrome, pp.373-378, 2009.
DOI : 10.1016/j.ejmg.2009.05.009

A. E. Tomkinson, T. R. Howes, and N. Wiest, DNA ligases as therapeutic targets, Transl Cancer Res, vol.2, p.1219, 2013.

P. Y. Wu, Structural and Functional Interaction between the Human DNA Repair Proteins DNA Ligase IV and XRCC4, Molecular and Cellular Biology, vol.29, issue.11, pp.3163-3172, 2009.
DOI : 10.1128/MCB.01895-08

URL : http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2682001

J. Cottarel, A noncatalytic function of the ligation complex during nonhomologous end joining, The Journal of Cell Biology, vol.15, issue.2, pp.173-186, 2013.
DOI : 10.1038/nsmb1261

S. Zhang, Congenital bone marrow failure in DNA-PKcs mutant mice associated with deficiencies in DNA repair, The Journal of Cell Biology, vol.193, issue.2, pp.295-305, 2011.
DOI : 10.1182/blood-2003-08-2955

X. Chen, Rational Design of Human DNA Ligase Inhibitors that Target Cellular DNA Replication and Repair, Cancer Research, vol.68, issue.9, pp.3169-3177, 2008.
DOI : 10.1158/0008-5472.CAN-07-6636

M. Srivastava, An Inhibitor of Nonhomologous End-Joining Abrogates Double-Strand Break Repair and Impedes Cancer Progression, Cell, vol.151, issue.7, pp.1474-1487, 2012.
DOI : 10.1016/j.cell.2012.11.054

M. Modesti, Tetramerization and DNA Ligase IV Interaction of the DNA Double-strand Break Repair Protein XRCC4 are Mutually Exclusive, Journal of Molecular Biology, vol.334, issue.2, pp.215-228, 2003.
DOI : 10.1016/j.jmb.2003.09.031

B. L. Sibanda, Crystal structure of an Xrcc4-DNA ligase IV complex, Nature Structural Biology, vol.8, issue.12, pp.1015-1019, 2001.
DOI : 10.1038/nsb725

T. Ochi, X. Gu, and T. L. Blundell, Structure of the Catalytic Region of DNA Ligase IV in Complex with an Artemis Fragment Sheds Light on Double-Strand Break Repair, Structure, vol.21, issue.4, pp.672-679, 2013.
DOI : 10.1016/j.str.2013.02.014

G. J. Williams, Structural insights into NHEJ: Building up an integrated picture of the dynamic DSB repair super complex, one component and interaction at a time, DNA Repair, vol.17, pp.110-120, 2014.
DOI : 10.1016/j.dnarep.2014.02.009

U. Grawunder, D. Zimmer, and M. R. Lieber, DNA ligase IV binds to XRCC4 via a motif located between rather than within its BRCT domains, Current Biology, vol.8, issue.15, pp.873-876, 1998.
DOI : 10.1016/S0960-9822(07)00349-1

M. J. Mcfadden, W. K. Lee, J. D. Brennan, and M. S. Junop, Delineation of key XRCC4/Ligase IV interfaces for targeted disruption of non-homologous end joining DNA repair, Proteins: Structure, Function, and Bioinformatics, vol.18, issue.2, pp.187-194, 2013.
DOI : 10.1002/prot.24349

K. R. Jones, Radiosensitization of MDA-MB-231 breast tumor cells by adenovirus-mediated overexpression of a fragment of the XRCC4 protein, Molecular Cancer Therapeutics, vol.4, issue.10, pp.1541-1547, 2005.
DOI : 10.1158/1535-7163.MCT-05-0193

J. H. Lin, A. L. Perryman, J. R. Schames, and J. A. Mccammon, The relaxed complex method: Accommodating receptor flexibility for drug design with an improved scoring scheme, Biopolymers, vol.4, issue.1, pp.47-62, 2003.
DOI : 10.1002/bip.10218

J. D. Durrant and J. A. Mccammon, Potential drug-like inhibitors of Group 1 influenza neuraminidase identified through computer-aided drug design, Computational Biology and Chemistry, vol.34, issue.2, pp.97-105, 2010.
DOI : 10.1016/j.compbiolchem.2010.03.005

J. R. Schames, Discovery of a Novel Binding Trench in HIV Integrase, Journal of Medicinal Chemistry, vol.47, issue.8, pp.1879-1881, 2004.
DOI : 10.1021/jm0341913

K. H. Barakat, Virtual Screening and Biological Evaluation of Inhibitors Targeting the XPA-ERCC1 Interaction, PLoS ONE, vol.4, issue.12, p.51329, 2012.
DOI : 10.1371/journal.pone.0051329.t002

URL : https://hal.archives-ouvertes.fr/hal-00853978

J. J. Irwin and B. K. Shoichet, ZINC ??? A Free Database of Commercially Available Compounds for Virtual Screening, Journal of Chemical Information and Modeling, vol.45, issue.1, pp.177-182, 2005.
DOI : 10.1021/ci049714+

A. P. Hill and R. J. Young, Getting physical in drug discovery: a contemporary perspective on solubility and hydrophobicity, Drug Discovery Today, vol.15, issue.15-16, pp.648-655, 2010.
DOI : 10.1016/j.drudis.2010.05.016

O. Trott and A. J. Olson, AutoDock Vina: Improving the speed and accuracy of docking with a new scoring function, efficient optimization, and multithreading, Journal of Computational Chemistry, vol.17, pp.455-461, 2010.
DOI : 10.1002/jcc.21334

D. Rognan, Rational design of protein???protein interaction inhibitors, Med. Chem. Commun., vol.109, issue.suppl. 1, pp.51-60, 2015.
DOI : 10.1039/C4MD00328D

R. Galeazzi, Molecular Dynamics as a Tool in Rational Drug Design: Current Status and Some Major Applications, Current Computer Aided-Drug Design, vol.5, issue.4, pp.225-240, 2009.
DOI : 10.2174/157340909789577847

F. H. Niesen, H. Berglund, and M. Vedadi, The use of differential scanning fluorimetry to detect ligand interactions that promote protein stability, Nature Protocols, vol.4, issue.9, pp.2212-2221, 2007.
DOI : 10.1038/nprot.2006.202

R. Campos-olivas, NMR Screening and Hit Validation in Fragment Based Drug Discovery, Current Topics in Medicinal Chemistry, vol.11, issue.1, pp.43-67, 2011.
DOI : 10.2174/156802611793611887

P. Cimmperman, A Quantitative Model of Thermal Stabilization and Destabilization of Proteins by Ligands, Biophysical Journal, vol.95, issue.7, pp.3222-3231, 2008.
DOI : 10.1529/biophysj.108.134973

M. Khanna, Targeting Multiple Conformations Leads to Small Molecule Inhibitors of the uPAR??uPA Protein???Protein Interaction That Block Cancer Cell Invasion, ACS Chemical Biology, vol.6, issue.11, pp.1232-1243, 2011.
DOI : 10.1021/cb200180m

I. J. Enyedy, Discovery of Small-Molecule Inhibitors of Bcl-2 through Structure-Based Computer Screening, Journal of Medicinal Chemistry, vol.44, issue.25, pp.4313-4324, 2001.
DOI : 10.1021/jm010016f

W. Tian, Structure-Based Discovery of a Novel Inhibitor Targeting the ??-Catenin/Tcf4 Interaction, Biochemistry, vol.51, issue.2, pp.724-731, 2012.
DOI : 10.1021/bi201428h

M. A. Kuenemann, In silico design of low molecular weight protein???protein interaction inhibitors: Overall concept and recent advances, Progress in Biophysics and Molecular Biology, vol.119, issue.1, pp.20-32, 2015.
DOI : 10.1016/j.pbiomolbio.2015.02.006

L. P. Jordheim, Small Molecule Inhibitors of ERCC1-XPF Protein-Protein Interaction Synergize Alkylating Agents in Cancer Cells, Molecular Pharmacology, vol.84, issue.1, pp.12-24, 2013.
DOI : 10.1124/mol.112.082347

M. Hammel, Y. Yu, S. Fang, S. P. Lees-miller, and J. A. Tainer, XLF Regulates Filament Architecture of the XRCC4, Ligase IV Complex. Structure, vol.18, pp.1431-1442, 2010.

V. T. Chu, Increasing the efficiency of homology-directed repair for CRISPR-Cas9-induced precise gene editing in mammalian cells, Nature Biotechnology, vol.3, issue.5, pp.543-548, 2015.
DOI : 10.1126/science.1231143

T. Maruyama, Increasing the efficiency of precise genome editing with CRISPR-Cas9 by inhibition of nonhomologous end joining, Nature Biotechnology, vol.3, issue.5, pp.538-542, 2015.
DOI : 10.1534/genetics.114.169771

S. N. Andres, M. Modesti, C. J. Tsai, G. Chu, and M. S. Junop, Crystal Structure of Human XLF: A Twist in Nonhomologous DNA End-Joining, Molecular Cell, vol.28, issue.6, pp.1093-1101, 2007.
DOI : 10.1016/j.molcel.2007.10.024

M. S. Junop, Crystal structure of the Xrcc4 DNA repair protein and implications for end joining, The EMBO Journal, vol.19, issue.22, pp.5962-5970, 2000.
DOI : 10.1093/emboj/19.22.5962

V. Summa, Discovery of Raltegravir, a Potent, Selective Orally Bioavailable HIV-Integrase Inhibitor for the Treatment of HIV-AIDS Infection, Journal of Medicinal Chemistry, vol.51, issue.18, pp.5843-5855, 2008.
DOI : 10.1021/jm800245z

Z. Wang, Hydroxyl may not be indispensable for raltegravir: Design, synthesis and SAR Studies of raltegravir derivatives as HIV-1 inhibitors, European Journal of Medicinal Chemistry, vol.50, pp.361-369, 2012.
DOI : 10.1016/j.ejmech.2012.02.015

G. R. Humphrey, Development of a Second-Generation, Highly Efficient Manufacturing Route for the HIV Integrase Inhibitor Raltegravir Potassium, Organic Process Research & Development, vol.15, issue.1, pp.73-83, 2011.
DOI : 10.1021/op100257r

U. C. Singh and P. A. Kollman, An approach to computing electrostatic charges for molecules, Journal of Computational Chemistry, vol.77, issue.2, pp.129-145, 1984.
DOI : 10.1002/jcc.540050204

J. B. Baell and G. A. Holloway, New Substructure Filters for Removal of Pan Assay Interference Compounds (PAINS) from Screening Libraries and for Their Exclusion in Bioassays, Journal of Medicinal Chemistry, vol.53, issue.7, pp.2719-2740, 2010.
DOI : 10.1021/jm901137j

J. B. Baell and M. A. Walters, Chemistry: Chemical con artists foil drug discovery, Nature, vol.513, issue.7519, pp.481-483, 2014.
DOI : 10.1038/513481a

G. M. Rishton, Reactive compounds and in vitro false positives in HTS, Drug Discovery Today, vol.2, issue.9, pp.382-384, 1997.
DOI : 10.1016/S1359-6446(97)01083-0

S. W. Muchmore, J. J. Edmunds, K. D. Stewart, and P. J. Hajduk, Cheminformatic Tools for Medicinal Chemists, Journal of Medicinal Chemistry, vol.53, issue.13, pp.4830-4841, 2010.
DOI : 10.1021/jm100164z

G. M. Rishton, Nonleadlikeness and leadlikeness in biochemical screening, Drug Discovery Today, vol.8, issue.2, pp.86-96, 2003.
DOI : 10.1016/S1359644602025722

M. Mcgann, FRED and HYBRID docking performance on standardized datasets, Journal of Computer-Aided Molecular Design, vol.49, issue.8, pp.897-906, 2012.
DOI : 10.1007/s10822-012-9584-8

B. R. Miller, : An Efficient Program for End-State Free Energy Calculations, Journal of Chemical Theory and Computation, vol.8, issue.9, pp.3314-3321, 2012.
DOI : 10.1021/ct300418h

J. Ryckaert, G. Ciccotti, and H. J. Berendsen, Numerical integration of the cartesian equations of motion of a system with constraints: molecular dynamics of n-alkanes, Journal of Computational Physics, vol.23, issue.3, pp.327-341, 1977.
DOI : 10.1016/0021-9991(77)90098-5

A. We, P. Demange, and P. Ramos, The authors thank Dr Neil Johnson for the careful reading of the manuscript. This work was supported by grants from the « Institut National du Cancer » (PLBio2010 XXL-screen program) and the « Ligue Nationale Contre le Cancer, Equipe labellisée 2013). GM was supported by PhD fellowships from Ministère et de l' enseignement supérieur et de la Recherche