QIMR Berghofer

CX-5461 Enhances the Efficacy of APR-246 via Induction of DNA Damage and Replication Stress in Triple-Negative Breast Cancer.

Abstract

Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer lacking targeted therapy. Here, we evaluated the anti-cancer activity of APR-246, a P53 activator, and CX-5461, a RNA polymerase I inhibitor, in the treatment of TNBC cells. We tested the efficacy of individual and combination therapy of CX-5461 and APR-246 in vitro, using a panel of breast cancer cell lines. Using publicly available breast cancer datasets, we found that components of RNA Pol I are predominately upregulated in basal-like breast cancer, compared to other subtypes, and this upregulation is associated with poor overall and relapse-free survival. Notably, we found that the treatment of breast cancer cells lines with CX-5461 significantly hampered cell proliferation and synergistically enhanced the efficacy of APR-246. The combination treatment significantly induced apoptosis that is associated with cleaved PARP and Caspase 3 along with Annexin V positivity. Likewise, we also found that combination treatment significantly induced DNA damage and replication stress in these cells. Our data provide a novel combination strategy by utilizing APR-246 in combination CX-5461 in killing TNBC cells that can be further developed into more effective therapy in TNBC therapeutic armamentarium.

Authors Makhale, Ashwini; Nanayakkara, Devathri; Raninga, Prahlad; Khanna, Kum Kum; Kalimutho, Murugan
Journal INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
Pages
Volume 22
Date 1/01/2021
Grant ID
Funding Body
URL http://www.ncbi.nlm.nih.gov/pubmed/?term=10.3390/ijms22115782