Journal of Life Science (생명과학회지)

Korean Society of Life Science (한국생명과학회)
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Conjugated Linoleic Acid Induces Apoptosis by Activating AMPK in MCF-7 Breast Cancer Cells

MCF-7 유방암 세포에서 AMPK 활성에 의한 conjugated linoleic acid의 apoptosis 유도에 관한 연구

  • Lin, Sun-Kyo (Marketing iBIO) ;
  • Kim, Hyun-Sook (Department of Pathology College of Medicine, Kyung Hee University) ;
  • Park, Ock-Jin (Department of Food and Nutrition, College of Life Science and Nano Technology, Hannam University) ;
  • Kim, Young-Min (Department of Biological Sciences, College of Life Science and Nano Technology, Hannam University)
  • 인선교 (iBIO 마케팅부) ;
  • 김현숙 (경희대학교 의과대학 병리학교실) ;
  • 박옥진 (한남대학교 생명나노과학대학 식품영양학과) ;
  • 김영민 (한남대학교 생명나노과학대학 생명과학과)
  • Published : 2008.12.30
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Abstract

Conjugated linoleic acid (CLA) is a naturally occurring compound found in dairy and beef products. It has been shown to suppress cancer cells and to induce apoptosis. Practically, there is emerging evidence that CLA can inhibit chemically induced carcinogenesis in various tissues. However, the molecular mechanisms of CLA on human MCF-7 breast cancer cells have not been clearly explained yet. In this report, we investigated the anti-cancer activity of CLA in MCF-7 cells. It was found that CLA could inhibit the growth of the MCF-7 cells and induce apoptosis, through modulating AMP-activated protein kinase (AMPK) and cyclooxygenase-2 (COX-2). AMPK acts as a cellular fuel gauge and responds to decreased cellular energy status by inhibiting ATP-consuming pathways and increasing ATP-synthesis. CLA treatment with variable concentrations and different time of same-dose CLA on MCF-7 cells resulted in a strong activation of AMPK and an inhibition of COX-2 expression. It supports that CLA induces apoptosis in CLA-treated MCF 7 cells. Therefore, the effects of CLA induced COX-2 expression via activating AMPK can provide new possibility into the understanding the molecular mechanisms of anti-cancer component.

본 연구는 쇠고기와 유제품에 들어 있는 CLA의 항암효과를 조사하기 위하여 수행되었다. 이 실험을 위하여 MCF-7 인체 유방암 세포주를 사용하였으며, CLA를 처리했을 때 MCF-7 세포의 증식은 CLA의 농도가 증가할수록, 또한 일정한 농도에서는 시간이 경과함에 따라 의존적으로 억제되었다. 이와 같이 암세포의 증식이 억제되는 이유는 Hoechst 33342 염색을 이용한 chromatin staining 및 ROS의 활성 측정실험 결과, apoptosis와 연관이 있는 것으로 확인되었다. CLA 처리에 의한 apoptosis가 AMPK 및 COX-2 단백질의 활성 발현과는 어떤 연관성이 있는지를 조사하기 위하여 Western blot 실험을 실시한 결과, CLA 처리에 따라 AMPK의 활성이 증가되었고, COX-2의 발현은 감소됨으로써, MCF-7 세포에서 apoptosis가 유도되었다는 것을 알 수 있었다. 본 연구를 통하여 조사한 CLA의 항암효과로부터, 향후 다른 식품에 포함된 성분들에서도 암세포의 증식 억제와 apoptosis의 유도를 연구할 수 있는 기초 자료를 제시한 것이라고 할 수 있다.

Keywords

References

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