Oops, you're using an old version of your browser so some of the features on this page may not be displaying properly.

MINIMAL Requirements: Google Chrome 24+Mozilla Firefox 20+Internet Explorer 11Opera 15–18Apple Safari 7SeaMonkey 2.15-2.23


35P - Increased sensitivity to olaparib by BRCA1/2 knockdown using a CRISPR/Cas9-mediated knock-in method in pancreatic cancer cell lines.


06 Oct 2021




Andréa Witz


Annals of Oncology (2021) 32 (suppl_6): S1345-S1371. 10.1016/annonc/annonc740


A. Witz1, J. Dardare2, M. Husson3, A. Francois4, J. Merlin4, P. Gilson1, A. Harlé1

Author affiliations

  • 1 Université de Lorraine CNRS UMR 7039 CRAN, Service de Biopathologie, Institut de Cancérologie de Lorraine, 54519 - Vandoeuvre les Nancy/FR
  • 2 Université de Lorraine CNRS UMR 7039 CRAN, Service de Biopathologie, Institut de Cancérologie de Lorraine, Vandoeuvre les Nancy/FR
  • 3 Institut de Cancérologie de Lorraine - Alexis Vautrin, 54519 - Vandoeuvre-les-Nancy/FR
  • 4 Institut de Cancérologie de Lorraine - Alexis Vautrin, 54519 - Vandoeuvre les Nancy/FR

Abstract 35P


Pancreatic cancer is one of the most incurable disease. About 80% of pancreatic adenocarcinoma are locally advanced at diagnosis or metastatic. Therefore, only 20% of patients undergo surgery and the majority have local relapse or metastasis. Chemotherapy regimens are used in adjuvant therapy with gemcitabine or FOLFIRINOX protocol, the standard of care for metastatic pancreatic cancer. Olaparib, a PARP inhibitor, is used as maintenance treatment in patient with metastatic pancreatic adenocarcinoma bearing a germline BRCA1/2 mutation. However, germline BRCA mutations have been described in less than 10% of patients with pancreatic adenocarcinoma. The objective of our study was to determine whether inducing a BRCA1/2 mutation in PDAC cells may restore sensitivity to olaparib.


We developed a CRISPR/Cas9-mediated knock-in technique to induce deleterious BRCA1 or BRCA2 mutations in pancreatic cancer cell lines. The c.763G>T (p.Glu255Ter) and c.2133C>A (p.Cys711Ter) mutations were selected to obtain truncated and non-functional BRCA1 and BRCA2 proteins respectively. A CRISPR/Cas9 ribonucleoprotein (RNP) was assembled for each mutation and transfected in two PDAC cell lines (T3M4 and Capan-2) and in a breast cancer cell lines (MCF7) as control.


Expected mutations were detected using ddPCR and NGS assays, proving the effectiveness of our CRISPR/Cas9 systems. Allelic frequencies were 90%, 65% and 20% for MCF7, T3M4 and Capan-2 cell-lines respectively. No off-target effects were found in the limit of the sequenced gene-panel. Calculated olaparib IC50 were significantly lower for all cell lines harboring a BRCA1 or a BRCA2 mutations compared to wild type BRCA1/2 cells (p<0.01).


We designed and validated a CRISPR-Cas9 system to induce in vitro deleterious BRCA1/2 genes mutations by knock-in in pancreatic cancer cell-lines and increase their sensitivity to olaparib. This strategy might offer an attractive therapeutic alternative for the management of patients with pancreatic cancer. Further investigations are needed to resolve CRISPR addressing issues in in vivo models and investigate both yield and toxicity.

Legal entity responsible for the study

Institut de Cancérologie de Lorraine.


Has not received any funding.


All authors have declared no conflicts of interest.

This site uses cookies. Some of these cookies are essential, while others help us improve your experience by providing insights into how the site is being used.

For more detailed information on the cookies we use, please check our Privacy Policy.

Customise settings
  • Necessary cookies enable core functionality. The website cannot function properly without these cookies, and you can only disable them by changing your browser preferences.