Effect of olaparib in combination with doxorubicin on MDA-MB-231 breast cancer cell line

REDONDO, ANALIA L; DE CAMPOS NEBEL, MARCELO; SOTTILE, MAYRA L; GOMEZ, LAURA C; DE PAOLA, MATILDE; VARGAS ROIG, LAURA M

Buenos Aires

Simposio; Buenos Aires Breast Cancer Symposium 2020; 2021

Breast cancer (BC) is the leading cause of cancer death in women in Argentina. Anthracycline-based regimens represent the major chemotherapeutic agents used in BC treatment. However, chemotherapy resistance development and adverse effects are still a challenge for the oncology. Poly [ADP-ribose] polymerase (PARP) is a key DNA repair protein mainly involved in base excision repair. Last years, PARP inhibitors (PARPi) have been approved for the treatment of BRCA-mutated BC. As PARP is involved in doxorubicin-induced cellular response, the aim of this work was to determine the effect of the PARPi olaparib on the sensitivity of BC cells to the anthracycline doxorubicin. MDA-MB-231 cells were treated with increasing concentrations of doxorubicin (5-40 nM), olaparib (1 µM) or doxorubicin and olaparib during 24 h. Clonogenic assay, viability assay and immunofluorescence were performed. Simultaneous administration of the drugs resulted in a combination index