Small Molecule Inhibitors of ERCC1-XPF Protein-Protein Interaction Synergize Alkylating Agents in Cancer Cells

Abstract

The benefit of cancer chemotherapy based on alkylating agents is limited because of the action of DNA repair enzymes, which mitigate the damage induced by these agents. The interaction between the proteins ERCC1 and XPF involves two major components of the nucleotide excision repair pathway. Here, novel inhibitors of this interaction were identified by virtual screening based on available structures with use of the National Cancer Institute diversity set and a panel of DrugBank small molecules. Subsequently, experimental validation of the in silico screening was undertaken. Top hits were evaluated on A549 and HCT116 cancer cells. In particular, the compound labeled NSC 130813 [4-[(6-chloro- 2-methoxy-9-acridinyl)amino]-2-[(4-methyl-1-piperazinyl)methyl]]was shown to act synergistically with cisplatin and mitomycin C; to increase UVC-mediated cytotoxicity; to modify DNA repair as indicated by the staining of phosphorylated H2AX; and to disrupt interaction between ERCC1 and XPF in cells. In addition, using the Biacore technique, we showed that this compound interacts with the domain of XPF responsible for interaction with ERCC1. This study shows that small molecules targeting the protein-protein interaction of ERCC1 and XPF can be developed to enhance the effects of alkylating agents on cancer cells.

Catechols and 3-hydroxypyridones as inhibitors of the DNA repair complex ERCC1-XPF

“…2 We sought to identify novel inhibitors of ERCC1-XPF using a high-throughput fluorescencebased in vitro endonuclease assay 3 and one of the hits obtained was compound 1 (Figure 1) with an IC50 value of approximately 30 µM and modest ligand efficiency. The catechol motif is present in known nuclease inhibitors 4 and although the dibromo-substitution and hydrazone motif were considered undesirable, 1 showed good selectivity for ERCC1-XPF in counterscreen assays against the nucleases FEN-1 and DNase I.…”

DNA Repair Endonucleases: Physiological Roles and Potential as Drug Targets

“…117 A virtual screen of potential inhibitors of the ERCC1-XPF interaction using available crystal structures and subsequent in vitro studies in lung, breast, and colon cancer cell lines identified a novel inhibitor of the ERCC1-XPF interaction, NERI02. 118 The specificity of NERI02 remains unclear; however, it has been shown to act synergistically with both cisplatin and mitomycin C (MMC). This may be due to it binding directly with DNA and therefore potentiating platinum sensitivity.…”

Baby Steps Toward Modelling The Full human Programmed Death-1 (PD-1) Pathway

“…With this limitation, molecular modelling and computer simulations can offer a comprehensive and alternative approach to understand these interactions [16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35] . Although there have been previous attempts to model the hPD-1/hPD-L1 and hPD-1/hPD-L2 complexes, none of these models correlated well with available experimental data.…”