CRISPR/Cas9-mediated knock-in of BRCA1/2 mutations restores response to olaparib in pancreatic cancer cell lines

Sci Rep. 2023 Oct 31;13(1):18741. doi: 10.1038/s41598-023-45964-w.

Abstract

Pancreatic cancer is one of the most aggressive diseases with a very poor outcome. Olaparib, a PARP inhibitor, as maintenance therapy showed benefits in patients with metastatic pancreatic adenocarcinoma bearing germline BRCA1/2 mutations. However, germline BRCA mutation has been described in only 4-7% of patients with pancreatic adenocarcinoma. A CRISPR/Cas9-mediated system was used to knock-in the c.763G > T p.(Glu255*) and c.2133C > A p.(Cys711*) mutations in cell lines to obtain truncated BRCA1 and BRCA2 proteins, respectively. A CRISPR/Cas9 ribonucleoprotein complex was assembled for each mutation and transfected into two pancreatic cell lines (T3M4 and Capan-2) and into a breast cancer cell lines (MCF7) as control. BRCA protein levels were significantly decreased in all BRCA-depleted cells (P < 0.05), proving the transfection efficiency of our CRISPR/Cas9 systems. As expected, the calculated olaparib IC50 were significantly reduced for all cell lines harbored BRCA1 or BRCA2 mutations compared to wild-type BRCA1/2 cells (P < 0.01). Furthermore, we observed a higher induction of apoptosis after 72 h olaparib treatment in BRCA-depleted cells than in wild-type cells. This strategy might offer new insights into the management of patients with pancreatic cancer and open up new perspectives based on the in vivo use of CRISPR/Cas9 strategy.

MeSH terms

  • Adenocarcinoma* / genetics
  • BRCA1 Protein / genetics
  • BRCA2 Protein / genetics
  • CRISPR-Cas Systems
  • Germ-Line Mutation
  • Humans
  • MCF-7 Cells
  • Mutation
  • Pancreatic Neoplasms* / drug therapy
  • Pancreatic Neoplasms* / genetics
  • Pancreatic Neoplasms* / pathology
  • Phthalazines / pharmacology

Substances

  • BRCA1 protein, human
  • BRCA1 Protein
  • olaparib
  • BRCA2 protein, human
  • BRCA2 Protein
  • Phthalazines