Pleiotropic variants (i.e. genetic polymorphisms influencing more than one phenotype) are often associated with cancer risk. A scan of pleiotropic variants was successfully conducted 10 years ago in relation to pancreatic ductal adenocarcinoma susceptibility. However, in the last decade, genetic association studies performed on several human traits have greatly increased the number of known pleiotropic variants. Based on the hypothesis that variants already associated with a least one trait have a higher probability of association with other traits, 61 052 variants reported to be associated by at least one genome-wide association study with at least one human trait were tested in the present study consisting of two phases (discovery and validation), comprising a total of 16 055 pancreatic ductal adenocarcinoma (PDAC) cases and 212 149 controls. The meta-analysis of the two phases showed two loci (10q21.1-rs4948550 (P = 6.52 × 10-5) and 7q36.3-rs288762 (P = 3.03 × 10-5) potentially associated with PDAC risk. 10q21.1-rs4948550 shows a high degree of pleiotropy and it is also associated with colorectal cancer risk while 7q36.3-rs288762 is situated 28,558 base pairs upstream of the Sonic Hedgehog (SHH) gene, which is involved in the cell-differentiation process and PDAC etiopathogenesis. In conclusion, none of the single nucleotide polymorphisms (SNPs) showed a formally statistically significant association after correction for multiple testing. However, given their pleiotropic nature and association with various human traits including colorectal cancer, the two SNPs showing the best associations with PDAC risk merit further investigation through fine mapping and ad hoc functional studies.

• Klíčová slova
• genetic susceptibility, pancreatic cancer, pleiotropy, single nucleotide polymorphism,
• MeSH
• celogenomová asociační studie MeSH
• duktální karcinom slinivky břišní * genetika   MeSH
• genetická pleiotropie * MeSH
• genetická predispozice k nemoci * MeSH
• jednonukleotidový polymorfismus MeSH
• lidé MeSH
• nádory slinivky břišní * genetika   MeSH
• studie případů a kontrol MeSH
• Check Tag
• lidé MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• metaanalýza MeSH

Targeting poly(ADP-ribose) glycohydrolase (PARG) is currently explored as a therapeutic approach to treat various cancer types, but we have a poor understanding of the specific genetic vulnerabilities that would make cancer cells susceptible to such a tailored therapy. Moreover, the identification of such vulnerabilities is of interest for targeting BRCA2;p53-deficient tumors that have acquired resistance to poly(ADP-ribose) polymerase inhibitors (PARPi) through loss of PARG expression. Here, by performing whole-genome CRISPR/Cas9 drop-out screens, we identify various genes involved in DNA repair to be essential for the survival of PARG;BRCA2;p53-deficient cells. In particular, our findings reveal EXO1 and FEN1 as major synthetic lethal interactors of PARG loss. We provide evidence for compromised replication fork progression, DNA single-strand break repair, and Okazaki fragment processing in PARG;BRCA2;p53-deficient cells, alterations that exacerbate the effects of EXO1/FEN1 inhibition and become lethal in this context. Since this sensitivity is dependent on BRCA2 defects, we propose to target EXO1/FEN1 in PARPi-resistant tumors that have lost PARG activity. Moreover, EXO1/FEN1 targeting may be a useful strategy for enhancing the effect of PARG inhibitors in homologous recombination-deficient tumors.

• Klíčová slova
• BRCA2, DNA Repair, EXO1, FEN1, PARG,
• MeSH
• "flap" endonukleasy genetika   metabolismus   terapeutické užití   MeSH
• enzymy opravy DNA genetika   MeSH
• exodeoxyribonukleasy genetika   MeSH
• glykosidhydrolasy genetika   metabolismus   MeSH
• lidé MeSH
• nádorový supresorový protein p53 * genetika   metabolismus   MeSH
• nádory * farmakoterapie   genetika   MeSH
• oprava DNA MeSH
• PARP inhibitory farmakologie   MeSH
• poškození DNA MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• "flap" endonukleasy MeSH
• enzymy opravy DNA MeSH
• EXO1 protein, human MeSH Prohlížeč
• exodeoxyribonukleasy MeSH
• FEN1 protein, human MeSH Prohlížeč
• glykosidhydrolasy MeSH
• nádorový supresorový protein p53 * MeSH
• PARP inhibitory MeSH