Robotic Mammosphere Assay for High-Throughput Screening in Triple-Negative Breast Cancer

• Published in: SLAS discovery 2017-08, Vol.22 (7), p.827-836
• Main Authors: Fitzpatrick, P. A., Akrap, N., Söderberg, E. M. V., Harrison, H., Thomson, G. J., Landberg, G.
• Format: Article
• Language: English
• Subjects: Antineoplastic Agents - pharmacology; Apoptosis - drug effects; Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology; cancer and cancer drugs; Cancer and Oncology; Cancer och onkologi; Cell Line, Tumor; cell-based assays; Chemistry; Female; high-content screening; High-Throughput Screening Assays - methods; Humans; identification; inhibitor; Neoplastic Stem Cells - pathology; Pyrans - pharmacology; resistance; Robotic Surgical Procedures - methods; stem cells; target; Triple Negative Breast Neoplasms - drug therapy; Triple Negative Breast Neoplasms - pathology
• ISSN: 2472-5552; 2472-5560
• DOI: 10.1177/2472555217692321

In order to identify novel treatment principles specifically affecting cancer stem cells in triple-negative breast cancer, we have developed a high-throughput screening method based on the mammosphere and anoikis resistance assays allowing us to screen compounds using a functional readout. The assay was validated against manual protocols and through the use of positive controls, such as the response to hypoxia and treatment with the known cancer stem cell–targeting compound salinomycin. Manual and robotic procedures were compared and produced similar results in cell handling, cell cultures, and counting techniques, with no statistically significant difference produced from either method. The variance between samples processed manually versus robotically was no greater than 0.012, while Levene’s test of significance was 0.2, indicating no significant difference between mammosphere data produced manually or robotically. Through the screening of 989 FDA-approved drugs and a follow-up screen assessing the antineoplastic subgroup, we have identified three therapeutic compounds with the ability to modulate the breast cancer stem cell fraction in the triple-negative breast cancer cell line MDA-MB-231, highlighting their potential usage as stem cell–specific adjuvant treatments.