A ruthenium polypyridyl intercalator stalls DNA replication forks, radiosensitizes human cancer cells and is enhanced by Chk1 inhibition
Ruthenium(II) polypyridyl complexes can intercalate DNA with high affinity and prevent cell proliferation; however, the direct impact of ruthenium-based intercalation on cellular DNA replication remains unknown. Here we show the multi-intercalator [Ru(dppz)2(PIP)](2+) (dppz = dipyridophenazine, PIP ...
| Main Authors: | , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Nature Publishing Group
2016
|
| Online Access: | http://psasir.upm.edu.my/id/eprint/54929/1/A%20ruthenium%20polypyridyl%20intercalator%20stalls%20DNA%20replication%20forks%2C%20radiosensitizes%20human%20cancer%20cells%20and%20is%20enhanced%20by%20Chk1%20inhibition.pdf |
| _version_ | 1825931124540440576 |
|---|---|
| author | Gill, Martin R. Harun, Siti Norain Halder, Swagata Boghozian, Ramon A. Ramadan, Kristijan Ahmad, Haslina Vallis, Katherine A. |
| author_facet | Gill, Martin R. Harun, Siti Norain Halder, Swagata Boghozian, Ramon A. Ramadan, Kristijan Ahmad, Haslina Vallis, Katherine A. |
| author_sort | Gill, Martin R. |
| collection | UPM |
| description | Ruthenium(II) polypyridyl complexes can intercalate DNA with high affinity and prevent cell proliferation; however, the direct impact of ruthenium-based intercalation on cellular DNA replication remains unknown. Here we show the multi-intercalator [Ru(dppz)2(PIP)](2+) (dppz = dipyridophenazine, PIP = 2-(phenyl)imidazo[4,5-f][1,10]phenanthroline) immediately stalls replication fork progression in HeLa human cervical cancer cells. In response to this replication blockade, the DNA damage response (DDR) cell signalling network is activated, with checkpoint kinase 1 (Chk1) activation indicating prolonged replication-associated DNA damage, and cell proliferation is inhibited by G1-S cell-cycle arrest. Co-incubation with a Chk1 inhibitor achieves synergistic apoptosis in cancer cells, with a significant increase in phospho(Ser139) histone H2AX (γ-H2AX) levels and foci indicating increased conversion of stalled replication forks to double-strand breaks (DSBs). Normal human epithelial cells remain unaffected by this concurrent treatment. Furthermore, pre-treatment of HeLa cells with [Ru(dppz)2(PIP)](2+) before external beam ionising radiation results in a supra-additive decrease in cell survival accompanied by increased γ-H2AX expression, indicating the compound functions as a radiosensitizer. Together, these results indicate ruthenium-based intercalation can block replication fork progression and demonstrate how these DNA-binding agents may be combined with DDR inhibitors or ionising radiation to achieve more efficient cancer cell killing. |
| first_indexed | 2024-03-06T09:21:59Z |
| format | Article |
| id | upm.eprints-54929 |
| institution | Universiti Putra Malaysia |
| language | English |
| last_indexed | 2024-03-06T09:21:59Z |
| publishDate | 2016 |
| publisher | Nature Publishing Group |
| record_format | dspace |
| spelling | upm.eprints-549292018-06-12T08:19:53Z http://psasir.upm.edu.my/id/eprint/54929/ A ruthenium polypyridyl intercalator stalls DNA replication forks, radiosensitizes human cancer cells and is enhanced by Chk1 inhibition Gill, Martin R. Harun, Siti Norain Halder, Swagata Boghozian, Ramon A. Ramadan, Kristijan Ahmad, Haslina Vallis, Katherine A. Ruthenium(II) polypyridyl complexes can intercalate DNA with high affinity and prevent cell proliferation; however, the direct impact of ruthenium-based intercalation on cellular DNA replication remains unknown. Here we show the multi-intercalator [Ru(dppz)2(PIP)](2+) (dppz = dipyridophenazine, PIP = 2-(phenyl)imidazo[4,5-f][1,10]phenanthroline) immediately stalls replication fork progression in HeLa human cervical cancer cells. In response to this replication blockade, the DNA damage response (DDR) cell signalling network is activated, with checkpoint kinase 1 (Chk1) activation indicating prolonged replication-associated DNA damage, and cell proliferation is inhibited by G1-S cell-cycle arrest. Co-incubation with a Chk1 inhibitor achieves synergistic apoptosis in cancer cells, with a significant increase in phospho(Ser139) histone H2AX (γ-H2AX) levels and foci indicating increased conversion of stalled replication forks to double-strand breaks (DSBs). Normal human epithelial cells remain unaffected by this concurrent treatment. Furthermore, pre-treatment of HeLa cells with [Ru(dppz)2(PIP)](2+) before external beam ionising radiation results in a supra-additive decrease in cell survival accompanied by increased γ-H2AX expression, indicating the compound functions as a radiosensitizer. Together, these results indicate ruthenium-based intercalation can block replication fork progression and demonstrate how these DNA-binding agents may be combined with DDR inhibitors or ionising radiation to achieve more efficient cancer cell killing. Nature Publishing Group 2016-08-25 Article PeerReviewed text en http://psasir.upm.edu.my/id/eprint/54929/1/A%20ruthenium%20polypyridyl%20intercalator%20stalls%20DNA%20replication%20forks%2C%20radiosensitizes%20human%20cancer%20cells%20and%20is%20enhanced%20by%20Chk1%20inhibition.pdf Gill, Martin R. and Harun, Siti Norain and Halder, Swagata and Boghozian, Ramon A. and Ramadan, Kristijan and Ahmad, Haslina and Vallis, Katherine A. (2016) A ruthenium polypyridyl intercalator stalls DNA replication forks, radiosensitizes human cancer cells and is enhanced by Chk1 inhibition. Scientific Reports, 6. pp. 1-13. ISSN 2045-2322 10.1038/srep31973 |
| spellingShingle | Gill, Martin R. Harun, Siti Norain Halder, Swagata Boghozian, Ramon A. Ramadan, Kristijan Ahmad, Haslina Vallis, Katherine A. A ruthenium polypyridyl intercalator stalls DNA replication forks, radiosensitizes human cancer cells and is enhanced by Chk1 inhibition |
| title | A ruthenium polypyridyl intercalator stalls DNA replication forks, radiosensitizes human cancer cells and is enhanced by Chk1 inhibition |
| title_full | A ruthenium polypyridyl intercalator stalls DNA replication forks, radiosensitizes human cancer cells and is enhanced by Chk1 inhibition |
| title_fullStr | A ruthenium polypyridyl intercalator stalls DNA replication forks, radiosensitizes human cancer cells and is enhanced by Chk1 inhibition |
| title_full_unstemmed | A ruthenium polypyridyl intercalator stalls DNA replication forks, radiosensitizes human cancer cells and is enhanced by Chk1 inhibition |
| title_short | A ruthenium polypyridyl intercalator stalls DNA replication forks, radiosensitizes human cancer cells and is enhanced by Chk1 inhibition |
| title_sort | ruthenium polypyridyl intercalator stalls dna replication forks radiosensitizes human cancer cells and is enhanced by chk1 inhibition |
| url | http://psasir.upm.edu.my/id/eprint/54929/1/A%20ruthenium%20polypyridyl%20intercalator%20stalls%20DNA%20replication%20forks%2C%20radiosensitizes%20human%20cancer%20cells%20and%20is%20enhanced%20by%20Chk1%20inhibition.pdf |
| work_keys_str_mv | AT gillmartinr arutheniumpolypyridylintercalatorstallsdnareplicationforksradiosensitizeshumancancercellsandisenhancedbychk1inhibition AT harunsitinorain arutheniumpolypyridylintercalatorstallsdnareplicationforksradiosensitizeshumancancercellsandisenhancedbychk1inhibition AT halderswagata arutheniumpolypyridylintercalatorstallsdnareplicationforksradiosensitizeshumancancercellsandisenhancedbychk1inhibition AT boghozianramona arutheniumpolypyridylintercalatorstallsdnareplicationforksradiosensitizeshumancancercellsandisenhancedbychk1inhibition AT ramadankristijan arutheniumpolypyridylintercalatorstallsdnareplicationforksradiosensitizeshumancancercellsandisenhancedbychk1inhibition AT ahmadhaslina arutheniumpolypyridylintercalatorstallsdnareplicationforksradiosensitizeshumancancercellsandisenhancedbychk1inhibition AT valliskatherinea arutheniumpolypyridylintercalatorstallsdnareplicationforksradiosensitizeshumancancercellsandisenhancedbychk1inhibition AT gillmartinr rutheniumpolypyridylintercalatorstallsdnareplicationforksradiosensitizeshumancancercellsandisenhancedbychk1inhibition AT harunsitinorain rutheniumpolypyridylintercalatorstallsdnareplicationforksradiosensitizeshumancancercellsandisenhancedbychk1inhibition AT halderswagata rutheniumpolypyridylintercalatorstallsdnareplicationforksradiosensitizeshumancancercellsandisenhancedbychk1inhibition AT boghozianramona rutheniumpolypyridylintercalatorstallsdnareplicationforksradiosensitizeshumancancercellsandisenhancedbychk1inhibition AT ramadankristijan rutheniumpolypyridylintercalatorstallsdnareplicationforksradiosensitizeshumancancercellsandisenhancedbychk1inhibition AT ahmadhaslina rutheniumpolypyridylintercalatorstallsdnareplicationforksradiosensitizeshumancancercellsandisenhancedbychk1inhibition AT valliskatherinea rutheniumpolypyridylintercalatorstallsdnareplicationforksradiosensitizeshumancancercellsandisenhancedbychk1inhibition |