Disulfiram modulated ROS–MAPK and NFκB pathways and targeted breast cancer cells with cancer stem cell-like properties

• Published in: British journal of cancer 2011-05, Vol.104 (10), p.1564-1574
• Main Authors: Yip, N C, Fombon, I S, Liu, P, Brown, S, Kannappan, V, Armesilla, A L, Xu, B, Cassidy, J, Darling, J L, Wang, W
• Format: Article
• Language: English
• Subjects: 631/67/71; 631/92/436/2388; 692/699/67/1347; Antineoplastic Agents - pharmacology; Biological and medical sciences; Biomedical and Life Sciences; Biomedicine; Breast Neoplasms - drug therapy; Breast Neoplasms - metabolism; Breast Neoplasms - pathology; Cancer Research; Cell Line, Tumor; Copper - pharmacology; Disulfiram - pharmacology; Drug Resistance; Electrophoretic Mobility Shift Assay; Epidemiology; Female; Gynecology. Andrology. Obstetrics; Humans; Mammary gland diseases; Medical sciences; Mitogen-Activated Protein Kinases - metabolism; Molecular Medicine; Neoplastic Stem Cells - drug effects; Neoplastic Stem Cells - metabolism; Neoplastic Stem Cells - pathology; NF-kappa B - metabolism; Oncology; Reactive Oxygen Species - metabolism; Translational Therapeutics; Tumors
• ISSN: 0007-0920; 1532-1827
• DOI: 10.1038/bjc.2011.126

Background: Previous studies indicate that disulfiram (DS), an anti-alcoholism drug, is cytotoxic to cancer cell lines and reverses anticancer drug resistance. Cancer stem cells (CSCs) are the major cause of chemoresistance leading to the failure of cancer chemotherapy. This study intended to examine the effect of DS on breast cancer stem cells (BCSCs). Methods: The effect of DS on BC cell lines and BCSCs was determined by MTT, western blot, CSCs culture and CSCs marker analysis. Results: Disulfiram was highly toxic to BC cell lines in vitro in a copper (Cu)-dependent manner. In Cu-containing medium (1  μ M ), the IC 50 concentrations of DS in BC cell lines were 200–500 n M . Disulfiram/copper significantly enhanced (3.7–15.5-fold) cytotoxicity of paclitaxel (PAC). Combination index isobologram analysis demonstrated a synergistic effect between DS/Cu and PAC. The increased Bax and Bcl2 protein expression ratio indicated that intrinsic apoptotic pathway may be involved in DS/Cu-induced apoptosis. Clonogenic assay showed DS/Cu-inhibited clonogenicity of BC cells. Mammosphere formation and the ALDH1 +VE and CD24 Low /CD44 High CSCs population in mammospheres were significantly inhibited by exposure to DS/Cu for 24 h. Disulfiram/copper induced reactive oxygen species (ROS) generation and activated its downstream apoptosis-related cJun N-terminal kinase and p38 MAPK pathways. Meanwhile, the constitutive NF κ B activity in BC cell lines was inhibited by DS/Cu. Conclusion: Disulfiram/copper inhibited BCSCs and enhanced cytotoxicity of PAC in BC cell lines. This may be caused by simultaneous induction of ROS and inhibition of NF κ B.