Unravelling the clinicopathological and functional significance of replication protein A (RPA) heterotrimeric complex in breast cancers

Algethami, Mashael; Toss, Michael S.; Woodcock, Corinne L.; Jaipal, Chandar; Brownlie, Juliette; Shoqafi, Ahmed; Alblihy, Adel; Mesquita, Katia A.; Green, Andrew R.; Mongan, Nigel P.; Jeyapalan, Jennie N.; Rakha, Emad A.; Madhusudan, Srinivasan

Abstract

Replication Protein A (RPA), a heterotrimeric complex consisting of RPA1, 2, and 3 subunits, is a single-stranded DNA (ssDNA)-binding protein that is critically involved in replication, checkpoint regulation and DNA repair. Here we have evaluated RPA in 776 pure ductal carcinomas in situ (DCIS), 239 DCIS that co-exist with invasive breast cancer (IBC), 50 normal breast tissue and 4221 IBC. Transcriptomic [METABRIC cohort (n = 1980)] and genomic [TCGA cohort (n = 1090)] evaluations were completed. Preclinically, RPA deficient cells were tested for cisplatin sensitivity and Olaparib induced synthetic lethality. Low RPA linked to aggressive DCIS, aggressive IBC, and shorter survival outcomes. At the transcriptomic level, low RPA tumours overexpress pseudogene/lncRNA as well as genes involved in chemical carcinogenesis, and drug metabolism. Low RPA remains linked with poor outcome. RPA deficient cells are sensitive to cisplatin and Olaparib induced synthetic lethality. We conclude that RPA directed precision oncology strategy is feasible in breast cancers.

Citation

Algethami, M., Toss, M. S., Woodcock, C. L., Jaipal, C., Brownlie, J., Shoqafi, A., …Madhusudan, S. (2023). Unravelling the clinicopathological and functional significance of replication protein A (RPA) heterotrimeric complex in breast cancers. npj Breast Cancer, 9, Article 18. https://doi.org/10.1038/s41523-023-00524-3

• Journal Article Type: Article
• Acceptance Date: Mar 14, 2023
• Online Publication Date: Mar 30, 2023
• Publication Date: 2023
• Deposit Date: Apr 9, 2023
• Publicly Available Date: Apr 20, 2023
• Journal: npj Breast Cancer
• Electronic ISSN: 2374-4677
• Publisher: Springer Science and Business Media LLC
• Peer Reviewed: Peer Reviewed
• Volume: 9
• Article Number: 18
• DOI: https://doi.org/10.1038/s41523-023-00524-3
• Keywords: Pharmacology (medical), Radiology, Nuclear Medicine and imaging, Oncology
• Public URL: https://nottingham-repository.worktribe.com/output/19010351
• Publisher URL: https://www.nature.com/articles/s41523-023-00524-3