Poly (ADP-ribose) polymerase (PARP) inhibitors have emerged as promising therapeutics for many diseases, including cancer, in clinical trials. One PARP inhibitor, olaparib (Lynparza, AstraZeneca), was recently approved by the FDA to treat ovarian cancer with mutations in BRCA genes. BRCA1 and BRCA2 have essential roles in repairing DNA double-strand breaks, and a deficiency of BRCA proteins sensitizes cancer cells to PARP inhibition. Here we show that the receptor tyrosine kinase c-Met associates with and phosphorylates PARP1 at Tyr907 (PARP1 pTyr907 or pY907). PARP1 pY907 increases PARP1 enzymatic activity and reduces binding to a PARP inhibitor, thereby rendering cancer cells resistant to PARP inhibition. The combination of c-Met and PARP1 inhibitors synergized to suppress the growth of breast cancer cells in vitro and xenograft tumor models, and we observed similar synergistic effects in a lung cancer xenograft tumor model. These results suggest that the abundance of PARP1 pY907 may predict tumor resistance to PARP inhibitors, and that treatment with a combination of c-Met and PARP inhibitors may benefit patients whose tumors show high c-Met expression and who do not respond to PARP inhibition alone.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4754671PMC
http://dx.doi.org/10.1038/nm.4032DOI Listing

Publication Analysis

Top Keywords

parp inhibitors
16
cancer cells
12
parp inhibition
12
parp
9
parp inhibitor
8
parp1 py907
8
combination c-met
8
xenograft tumor
8
parp1
7
cancer
6

Similar Publications

Background: Ovarian cancer (OC), particularly high-grade serous ovarian carcinoma (HGSOC), is the leading cause of mortality from gynecological malignancies worldwide. Despite the initial effectiveness of treatment, acquired resistance to poly(ADP-ribose) polymerase inhibitors (PARPis) represents a major challenge for the clinical management of HGSOC, highlighting the necessity for the development of novel therapeutic strategies. This study investigated the role of 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase 3 (PFKFB3), a pivotal regulator of glycolysis, in PARPi resistance and explored its potential as a therapeutic target to overcome PARPi resistance.

View Article and Find Full Text PDF

ZBP1-mediated PANoptosis is a crucial lethal form in diverse keratinocyte death modalities in UVB-induced skin injury.

Cell Death Dis

January 2025

Jiangsu Key Laboratory of Molecular Biology for Skin Diseases and STIs, Hospital for Skin Diseases, Institute of Dermatology, Chinese Academy of Medical Sciences & Peking Union Medical College, Nanjing, 210042, Jiangsu, China.

UVB irradiation induces diverse modalities of regulatory cell death in keratinocytes. Recently, the pattern of coexistence of pyroptosis, apoptosis, and necroptosis has been termed PANoptosis; however, whether PANoptosis occurs in keratinocytes in UVB-induced skin injury remains unclear. We observed that the key molecules of GSDMD-mediated pyroptosis, apoptosis, and necroptosis, which are N-terminal GSDMD, cleaved caspase-3/PARP, and phosphorylated MLKL, respectively, were elevated in keratinocytes of UVB-challenged mice and human skin tissue.

View Article and Find Full Text PDF

CHD6 has poly(ADP-ribose)- and DNA-binding domains and regulates PARP1/2-trapping inhibitor sensitivity via abasic site repair.

Nat Commun

January 2025

Robson DNA Science Centre, Charbonneau Cancer Institute, Department of Biochemistry & Molecular Biology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.

To tolerate oxidative stress, cells enable DNA repair responses often sensitive to poly(ADP-ribose) (PAR) polymerase 1 and 2 (PARP1/2) inhibition-an intervention effective against cancers lacking BRCA1/2. Here, we demonstrate that mutating the CHD6 chromatin remodeler sensitizes cells to PARP1/2 inhibitors in a manner distinct from BRCA1, and that CHD6 recruitment to DNA damage requires cooperation between PAR- and DNA-binding domains essential for nucleosome sliding activity. CHD6 displays direct PAR-binding, interacts with PARP-1 and other PAR-associated proteins, and combined DNA- and PAR-binding loss eliminates CHD6 relocalization to DNA damage.

View Article and Find Full Text PDF

Background: Black women and other minorities have higher age adjusted incidence risk for cervical and endometrial cancer than White women. However, the extent of racial and ethnic disparities in clinical trial enrollment among studies performed mainly in North America and Europe for gynecologic malignancy is unknown.

Objective: This study analyzed enrollment rates by race/ethnicity in trials that led to Food and Drug Administration (FDA) approvals for gynecological cancers from 2010 to 2024.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!