1. Academic Validation
  2. Pseudolaric acid B activates autophagy in MCF-7 human breast cancer cells to prevent cell death

Pseudolaric acid B activates autophagy in MCF-7 human breast cancer cells to prevent cell death

  • Oncol Lett. 2016 Mar;11(3):1731-1737. doi: 10.3892/ol.2016.4103.
Jinghua Yu 1 Chunhai Chen 2 Tianyang Xu 3 Minghui Yan 4 Bianbian Xue 5 Ying Wang 5 Chunyu Liu 2 Ting Zhong 6 Zengyan Wang 7 Xianying Meng 8 Donghua Hu 6 Xiaofang Yu 9
Affiliations

Affiliations

  • 1 Institute of Virology and AIDS Research, The First Hospital of Jilin University, Changchun, Jilin 130021, P.R. China.
  • 2 Department of Acupunture, The Affiliated Hospital of Changchun University of Chinese Medicine, Changchun, Jilin 130000, P.R. China.
  • 3 Department of Drug Analysis and Analytical Chemistry, Changchun University of Chinese Medicine, Changchun, Jilin 130117, P.R. China.
  • 4 Department of Biomedical Engineering, College of Pharmacy, Jilin University, Changchun, Jilin 130000, P.R. China.
  • 5 Department of Gastroenterology, The First Hospital of Jilin University, Changchun, Jilin 130021, P.R. China.
  • 6 Department of Medicinal Chemistry, Changchun University of Chinese Medicine, Changchun, Jilin 130117, P.R. China.
  • 7 Department of Internal Medicine, The First Hospital of Jilin University, Changchun, Jilin 130000, P.R. China.
  • 8 Department of Thyroid Surgery, The First Hospital of Jilin University, Changchun, Jilin 130021, P.R. China.
  • 9 Institute of Virology and AIDS Research, The First Hospital of Jilin University, Changchun, Jilin 130021, P.R. China; Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA.
Abstract

Pseudolaric acid B (PAB) has been demonstrated to exert antitumor effects in MCF-7 human breast Cancer cells. The present study aimed to investigate the mechanism of resistance to PAB-induced cell death. Following incubation with 4 µM of PAB for 3 days, the majority of MCF-7 cells became senescent, while some retained the same morphology as control cells, as assessed using a senescence detection kit. Additionally, 36 h of treatment with 4 µM of PAB increased the positive staining of Autophagy markers, as shown by monodansylcadaverine and acridine orange staining. Western blot analysis indicated that this treatment also increased expression of the autophagy-related proteins Beclin-1 and microtubule-associated protein 1 LIGHT chain 3. Furthermore, treatment with PAB and the Autophagy Inhibitor 3-methyl adenine significantly decreased the ratio of Autophagy, as assessed by flow cytometric analysis of monodansylcadaverine staining density (P<0.001), and increased the ratio of cell death, as assessed by MTT analysis (P<0.001). This indicated that Autophagy promotes cell survival as a resistance mechanism to PAB treatment. Additionally, the present study demonstrated that PAB treatment did not affect the mitochondrial membrane potential, which may be related to Autophagy. Increased Bcl-2 expression may explain why PAB did not affect the mitochondrial membrane potential. A Bcl-2 binding test demonstrated that PAB treatment inhibits the binding of Bcl-2 and Beclin-1, which may free Beclin-1 to participate in Autophagy. Therefore, the present study demonstrated that Autophagy may be activated by PAB treatment in human breast Cancer MCF-7 cells, contributing to resistance to cell death.

Keywords

MCF-7 human breast cancer cells; autophagy; pseudolaric acid B.

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