Squalene protects against oxidative DNA damage in MCF10A human mammary epithelial cells but not in MCF7 and MDA-MB-231 human breast cancer cells.
Until now, very little has been known about the antioxidant capacity of squalene and its effect on human breast tumourigenesis. In the present work, we investigated squalene's scavenging properties and its effect on cell proliferation, cell cycle profile, apoptosis, reactive oxygen species (ROS) level and oxidative DNA damage, using human breast cell lines. Our results showed that squalene neither possesses scavenging activity nor significantly alters cell proliferation rates, the cell cycle profile or cell apoptosis in human mammary epithelial cells (MCF10A), minimally invasive (MDA-MB-231) breast cancer cells, and highly invasive (MCF7) breast cancer cells. However, we found that squalene did exert the following effects on MCF10A epithelial cells in a dose-dependent manner: (a) it decreased intracellular ROS level, (b) it prevented H(2)O(2)-induced oxidative injury, and (c) it protected against oxidative DNA damage. Interestingly, squalene did not exert these effects on MCF7 and MDA-MB-231 cancer cells. Therefore, our data suggest that squalene, found in high amounts in virgin olive oils, could be partially responsible for the lower incidence of breast cancer in populations that consume the Mediterranean diet due to its protective activity against oxidative DNA damage in normal mammary cells.
Immunology Division, Department of Health Sciences, Faculty of Experimental Sciences, University of Jaén, Campus las Lagunillas s/n, 23071 Jaén, Spain.
Fernando
F
Warleta
María
M
Campos
Yosra
Y
Allouche
Cristina
C
Sánchez-Quesada
Jesús
J
Ruiz-Mora
Gabriel
G
Beltrán
José J
JJ
Gaforio
D017209:Apoptosis / Q000187:drug effects; D052160:Benzothiazoles / Q000737:chemistry; D001940:Breast / Q000187:drug effects* / Q000473:pathology; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000473:pathology; D002453:Cell Cycle / Q000187:drug effects; D002461:Cell Line, Transformed; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D004249:DNA Damage / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004336:Drug Antagonism; D004847:Epithelial Cells / Q000187:drug effects / Q000473:pathology; D005260:Female; D016166:Free Radical Scavengers / Q000737:chemistry / Q000494:pharmacology*; D006801:Humans; D006861:Hydrogen Peroxide / Q000494:pharmacology; D018384:Oxidative Stress; D013185:Squalene / Q000737:chemistry / Q000494:pharmacology*; D013451:Sulfonic Acids / Q000737:chemistry; D014410:Tumor Stem Cell Assay
D052160:Benzothiazoles; D016166:Free Radical Scavengers; D013451:Sulfonic Acids; C002502:2,2'-azino-di-(3-ethylbenzothiazoline)-6-sulfonic acid; D013185:Squalene; D006861:Hydrogen Peroxide