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Apigenin induces caspase-dependent apoptosis in human lung cancer A549 cells through Bax- and Bcl-2-triggered

Hsu-Feng Lu1, Yu-Jie Chie, Ming-Sung Yang

  • 1Department of Clinical Pathology, Cheng Hsin General Hospital, Taipei 112, Taiwan, R.O.C.

International Journal of Oncology
|April 30, 2010
PubMed

Insights

Apigenin triggers apoptosis in human lung cancer cells by damaging DNA and activating caspases. This natural compound disrupts mitochondrial function, leading to programmed cell death in A549 cells.

Area of Science:

  • Molecular Biology
  • Cell Biology
  • Biochemistry

Background:

  • The molecular mechanisms of apigenin-induced apoptosis in human lung cancer remain unclear.
  • Investigating signaling pathways is crucial for understanding apigenin's anti-cancer effects.

Purpose of the Study:

  • To elucidate the molecular mechanisms and signaling pathways of apigenin-induced cytotoxicity and apoptosis in A549 human lung cancer cells.
  • To determine the roles of reactive oxygen species (ROS), calcium ions (Ca2+), caspases, Bax proteins, and mitochondrial membrane potential.

Main Methods:

  • Cell viability assays, DAPI staining, Comet assay, and flow cytometry were used to assess apoptosis and DNA damage.
  • Western blotting analyzed protein levels (Bax, Bcl-2, caspases), and confocal microscopy tracked protein translocation.
  • Mitochondrial membrane potential and cytochrome c release were also evaluated.

Main Results:

  • Apigenin induced significant morphological changes, decreased cell viability, and dose- and time-dependent apoptosis in A549 cells.
  • Apigenin caused DNA condensation and damage, confirmed by DAPI staining and Comet assay.
  • The study identified caspase-3, -8, and -9 activation, indicating a caspase-dependent pathway, and observed mitochondrial dysfunction with cytochrome c, AIF, and Endo G release.

Conclusions:

  • Apigenin effectively induces apoptosis in human lung cancer cells (A549) through a caspase-dependent pathway.
  • Mitochondrial dysfunction and subsequent release of apoptotic factors are key events in apigenin-mediated cell death.
  • Apigenin shows potential as a therapeutic agent for lung cancer, warranting further investigation.

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