The metallo-intercalator [Ru(dppz)2(PIP)]2+ renders BRCA wild-type triple-negative breast cancer cells hypersensitive to PARP inhibition

There is a need to improve and extend the use of clinically-approved poly(ADP-ribose) polymerase (PARP) inhibitors (PARPi), including for BRCA wild-type triple-negative breast cancer (TNBC). The demonstration that ruthenium(II) polypyridyl complex (RPC) metallo-intercalators can rapidly stall DNA re...

Full description

Bibliographic Details
Main Authors: Yusoh, NA, Leong, SW, Chia, SL, Harun, SN, Rahman, MB, Vallis, KA, Gill, MR, Ahmad, H
Format: Journal article
Language:English
Published: American Chemical Society 2020
_version_ 1797074812959457280
author Yusoh, NA
Leong, SW
Chia, SL
Harun, SN
Rahman, MB
Vallis, KA
Gill, MR
Ahmad, H
author_facet Yusoh, NA
Leong, SW
Chia, SL
Harun, SN
Rahman, MB
Vallis, KA
Gill, MR
Ahmad, H
author_sort Yusoh, NA
collection OXFORD
description There is a need to improve and extend the use of clinically-approved poly(ADP-ribose) polymerase (PARP) inhibitors (PARPi), including for BRCA wild-type triple-negative breast cancer (TNBC). The demonstration that ruthenium(II) polypyridyl complex (RPC) metallo-intercalators can rapidly stall DNA replication fork progression provides the rationale for their combination alongside DNA damage response (DDR) inhibitors to achieve synergism in cancer cells. The aim of the present study was to evaluate use of the multi-intercalator [Ru(dppz)2(PIP)]2+ (dppz = dipyrido[3,2-a:2′,3′-c]phenazine, PIP = (2-(phenyl)imidazo[4,5-f][1,10]phenanthroline, Ru-PIP) alongside the PARP inhibitors (PARPi) olaparib and NU1025. Cell proliferation and clonogenic survival assays indicated a synergistic relationship between Ru-PIP and olaparib in MDA-MB-231 TNBC and MCF7 human breast cancer cells. Strikingly, low dose Ru-PIP renders both cell lines hypersensitive to olaparib, with a 300-fold increase in olaparib potency in TNBC; the largest non-genetic PARPi enhancement effect described to date. Negligible impact on the viability of normal human fibroblasts was observed for any combination tested. Increased levels of DNA double-strand break (DSB) damage and olaparib abrogation of Ru-PIP activated pChk1 signalling is consistent with PARPi-facilitated collapse of Ru-PIP-associated stalled replication forks. This results in enhanced G2/M cell-cycle arrest, apoptosis and decreased cell motility for the combination treatment compared to single-agent conditions. This work establishes that an RPC metallo-intercalator can be combined with PARPi for potent synergy in BRCA-proficient breast cancer cells, including TNBC.
first_indexed 2024-03-06T23:41:38Z
format Journal article
id oxford-uuid:6f87ce75-4a70-4fac-8582-f89c73f7f119
institution University of Oxford
language English
last_indexed 2024-03-06T23:41:38Z
publishDate 2020
publisher American Chemical Society
record_format dspace
spelling oxford-uuid:6f87ce75-4a70-4fac-8582-f89c73f7f1192022-03-26T19:31:08ZThe metallo-intercalator [Ru(dppz)2(PIP)]2+ renders BRCA wild-type triple-negative breast cancer cells hypersensitive to PARP inhibitionJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:6f87ce75-4a70-4fac-8582-f89c73f7f119EnglishSymplectic Elements at OxfordAmerican Chemical Society2020Yusoh, NALeong, SWChia, SLHarun, SNRahman, MBVallis, KAGill, MRAhmad, HThere is a need to improve and extend the use of clinically-approved poly(ADP-ribose) polymerase (PARP) inhibitors (PARPi), including for BRCA wild-type triple-negative breast cancer (TNBC). The demonstration that ruthenium(II) polypyridyl complex (RPC) metallo-intercalators can rapidly stall DNA replication fork progression provides the rationale for their combination alongside DNA damage response (DDR) inhibitors to achieve synergism in cancer cells. The aim of the present study was to evaluate use of the multi-intercalator [Ru(dppz)2(PIP)]2+ (dppz = dipyrido[3,2-a:2′,3′-c]phenazine, PIP = (2-(phenyl)imidazo[4,5-f][1,10]phenanthroline, Ru-PIP) alongside the PARP inhibitors (PARPi) olaparib and NU1025. Cell proliferation and clonogenic survival assays indicated a synergistic relationship between Ru-PIP and olaparib in MDA-MB-231 TNBC and MCF7 human breast cancer cells. Strikingly, low dose Ru-PIP renders both cell lines hypersensitive to olaparib, with a 300-fold increase in olaparib potency in TNBC; the largest non-genetic PARPi enhancement effect described to date. Negligible impact on the viability of normal human fibroblasts was observed for any combination tested. Increased levels of DNA double-strand break (DSB) damage and olaparib abrogation of Ru-PIP activated pChk1 signalling is consistent with PARPi-facilitated collapse of Ru-PIP-associated stalled replication forks. This results in enhanced G2/M cell-cycle arrest, apoptosis and decreased cell motility for the combination treatment compared to single-agent conditions. This work establishes that an RPC metallo-intercalator can be combined with PARPi for potent synergy in BRCA-proficient breast cancer cells, including TNBC.
spellingShingle Yusoh, NA
Leong, SW
Chia, SL
Harun, SN
Rahman, MB
Vallis, KA
Gill, MR
Ahmad, H
The metallo-intercalator [Ru(dppz)2(PIP)]2+ renders BRCA wild-type triple-negative breast cancer cells hypersensitive to PARP inhibition
title The metallo-intercalator [Ru(dppz)2(PIP)]2+ renders BRCA wild-type triple-negative breast cancer cells hypersensitive to PARP inhibition
title_full The metallo-intercalator [Ru(dppz)2(PIP)]2+ renders BRCA wild-type triple-negative breast cancer cells hypersensitive to PARP inhibition
title_fullStr The metallo-intercalator [Ru(dppz)2(PIP)]2+ renders BRCA wild-type triple-negative breast cancer cells hypersensitive to PARP inhibition
title_full_unstemmed The metallo-intercalator [Ru(dppz)2(PIP)]2+ renders BRCA wild-type triple-negative breast cancer cells hypersensitive to PARP inhibition
title_short The metallo-intercalator [Ru(dppz)2(PIP)]2+ renders BRCA wild-type triple-negative breast cancer cells hypersensitive to PARP inhibition
title_sort metallo intercalator ru dppz 2 pip 2 renders brca wild type triple negative breast cancer cells hypersensitive to parp inhibition
work_keys_str_mv AT yusohna themetallointercalatorrudppz2pip2rendersbrcawildtypetriplenegativebreastcancercellshypersensitivetoparpinhibition
AT leongsw themetallointercalatorrudppz2pip2rendersbrcawildtypetriplenegativebreastcancercellshypersensitivetoparpinhibition
AT chiasl themetallointercalatorrudppz2pip2rendersbrcawildtypetriplenegativebreastcancercellshypersensitivetoparpinhibition
AT harunsn themetallointercalatorrudppz2pip2rendersbrcawildtypetriplenegativebreastcancercellshypersensitivetoparpinhibition
AT rahmanmb themetallointercalatorrudppz2pip2rendersbrcawildtypetriplenegativebreastcancercellshypersensitivetoparpinhibition
AT valliska themetallointercalatorrudppz2pip2rendersbrcawildtypetriplenegativebreastcancercellshypersensitivetoparpinhibition
AT gillmr themetallointercalatorrudppz2pip2rendersbrcawildtypetriplenegativebreastcancercellshypersensitivetoparpinhibition
AT ahmadh themetallointercalatorrudppz2pip2rendersbrcawildtypetriplenegativebreastcancercellshypersensitivetoparpinhibition
AT yusohna metallointercalatorrudppz2pip2rendersbrcawildtypetriplenegativebreastcancercellshypersensitivetoparpinhibition
AT leongsw metallointercalatorrudppz2pip2rendersbrcawildtypetriplenegativebreastcancercellshypersensitivetoparpinhibition
AT chiasl metallointercalatorrudppz2pip2rendersbrcawildtypetriplenegativebreastcancercellshypersensitivetoparpinhibition
AT harunsn metallointercalatorrudppz2pip2rendersbrcawildtypetriplenegativebreastcancercellshypersensitivetoparpinhibition
AT rahmanmb metallointercalatorrudppz2pip2rendersbrcawildtypetriplenegativebreastcancercellshypersensitivetoparpinhibition
AT valliska metallointercalatorrudppz2pip2rendersbrcawildtypetriplenegativebreastcancercellshypersensitivetoparpinhibition
AT gillmr metallointercalatorrudppz2pip2rendersbrcawildtypetriplenegativebreastcancercellshypersensitivetoparpinhibition
AT ahmadh metallointercalatorrudppz2pip2rendersbrcawildtypetriplenegativebreastcancercellshypersensitivetoparpinhibition