Toxic PARP trapping upon cAMP-induced DNA damage reinstates the efficacy of endocrine therapy and CDK4/6 inhibitors in treatment-refractory ER+ breast cancer

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Atıf İçin Kopyala

Saatci O., Cetin M., ÜNER M., Tokat U. M., Chatzistamou I., Ersan P. G., ...Daha Fazla

Nature Communications, cilt.14, sa.1, 2023 (SCI-Expanded)

• Yayın Türü: Makale / Tam Makale
• Cilt numarası: 14 Sayı: 1
• Basım Tarihi: 2023
• Doi Numarası: 10.1038/s41467-023-42736-y
• Dergi Adı: Nature Communications
• Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, BIOSIS, CAB Abstracts, Chemical Abstracts Core, Geobase, INSPEC, MEDLINE, Veterinary Science Database, Directory of Open Access Journals
• Hacettepe Üniversitesi Adresli: Evet

Özet

Resistance to endocrine therapy and CDK4/6 inhibitors, the standard of care (SOC) in estrogen receptor-positive (ER+) breast cancer, greatly reduces patient survival. Therefore, elucidating the mechanisms of sensitivity and resistance to SOC therapy and identifying actionable targets are urgently needed. Here, we show that SOC therapy causes DNA damage and toxic PARP1 trapping upon generation of a functional BRCAness (i.e., BRCA1/2 deficiency) phenotype, leading to increased histone parylation and reduced H3K9 acetylation, resulting in transcriptional blockage and cell death. Mechanistically, SOC therapy downregulates phosphodiesterase 4D (PDE4D), a novel ER target gene in a feedforward loop with ER, resulting in increased cAMP, PKA-dependent phosphorylation of mitochondrial COXIV-I, ROS generation and DNA damage. However, during SOC resistance, an ER-to-EGFR switch induces PDE4D overexpression via c-Jun. Notably, combining SOC with inhibitors of PDE4D, EGFR or PARP1 overcomes SOC resistance irrespective of the BRCA1/2 status, providing actionable targets for restoring SOC efficacy.