title: The effect of seal oil on paclitaxel induced cytotoxicity and apoptosis in breast carcinoma MCF-7 and MDA-MB-231 cell lines.
abstract: Some studies have suggested that omega-3 polyunsaturated fatty acids (PUFAs) have an inhibitory effect on the growth of cancer cells and therefore have the potential to increase the efficacy of cancer chemotherapeutic drugs. Considering that omega-3 PUFAs are present abundantly in harp seal oil, we investigated the effect of seal oil on the cytotoxicity and apoptosis induced by paclitaxel in 2 breast cancer cell lines, MCF-7 and MDA-MB-231, respectively. Cytotoxicity evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay revealed that the concentration of paclitaxel that is required for 50% inhibition of cell growth in the presence of seal oil was significantly lower than that of paclitaxel alone. Apoptosis assessment based on morphological changes and DNA fragmentation results indicated that more cells treated with paclitaxel in combination with seal oil underwent apoptosis than with paclitaxel alone. Western blot analysis showed that the expression of B cell lymphoma-2 (Bcl-2) protein, an apoptosis inhibitory protein, in both cell lines was decreased more significant by paclitaxel in combination with seal oil than by paclitaxel alone. In addition, seal oil alone was found to induce apoptosis in both cell lines tested, which appeared to be due to the increased intracellular lipid peroxides produced. It is therefore concluded that paclitaxel in combination with seal oil demonstrated enhanced cytotoxicity and apoptosis in MCF-7 and MDA-MB-231 cells compared to paclitaxel alone, and the use of seal oil may be beneficial in the treatment of breast cancer.
authors.affiliation: School of Pharmacy, Memorial, University of Newfoundland, St. John's, Newfoundland, A1B 3V6, Canada.
authors.forename: Zheyu
authors.initials: Z
authors.lastname: Wang
authors.forename: Krista
authors.initials: K
authors.lastname: Butt
authors.forename: Lili
authors.initials: L
authors.lastname: Wang
authors.forename: Hu
authors.initials: H
authors.lastname: Liu
mesh_terms: D000818:Animals; D000972:Antineoplastic Agents, Phytogenic / Q000627:therapeutic use*; D017209:Apoptosis / Q000187:drug effects; D015153:Blotting, Western; D001943:Breast Neoplasms / Q000188:drug therapy*; D045744:Cell Line, Tumor; D053938:DNA Fragmentation / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004357:Drug Synergism; D015525:Fatty Acids, Omega-3 / Q000494:pharmacology*; D005260:Female; D006801:Humans; D020287:In Situ Nick-End Labeling; D015227:Lipid Peroxidation / Q000187:drug effects; D017239:Paclitaxel / Q000627:therapeutic use*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism; D046048:Seals, Earless / Q000378:metabolism; D017392:Thiobarbituric Acid Reactive Substances / Q000032:analysis
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D015525:Fatty Acids, Omega-3; D019253:Proto-Oncogene Proteins c-bcl-2; D017392:Thiobarbituric Acid Reactive Substances; D017239:Paclitaxel