Ramucirumab induces apoptosis in Caco-2 cells via mitochondrial impairment and caspase activation

Amal M Al-Dogmi1, Khalid Mashay Al-Anazi1, Wajhul Qamar2

  • 1Department of Zoology, College of Science, King Saud University, P.O. Box 2455, 11451, Riyadh, Saudi Arabia.

Insights

Ramucirumab induces colorectal cancer cell death by triggering apoptosis through mitochondrial dysfunction and caspase activation, revealing anti-cancer effects beyond angiogenesis inhibition.

Area of Science:

  • Oncology
  • Molecular Biology
  • Cell Biology

Background:

  • Ramucirumab, a VEGFR-2 inhibitor, is known for anti-angiogenesis effects in various cancers.
  • Direct cytotoxic mechanisms of ramucirumab in colorectal cancer, particularly involving mitochondrial dysfunction and ROS-mediated apoptosis, require further elucidation.

Purpose of the Study:

  • To investigate the role of mitochondrial dysfunction, oxidative stress, and caspase activation in ramucirumab-induced cytotoxicity in Caco-2 colorectal cancer cells.

Main Methods:

  • Cell viability (MTT) and cytotoxicity (LDH) assays were performed.
  • Flow cytometry analyzed apoptosis and cell cycle distribution.
  • Staining assessed nuclear condensation, mitochondrial membrane potential (ΔΨm), and intracellular reactive oxygen species (ROS).
  • Expression of caspase-3, caspase-7, and VEGF levels were quantified.

Main Results:

  • Ramucirumab decreased Caco-2 cell viability (IC50 = 780 µg/ml) and increased LDH release.
  • Apoptosis significantly increased, with cell cycle arrest observed primarily in the S-phase.
  • Mitochondrial dysfunction (decreased ΔΨm), elevated ROS, and increased VEGF were noted.
  • Caspase-3 and caspase-7 activation indicated caspase-mediated apoptosis.

Conclusions:

  • Ramucirumab exhibits anti-cancer activity against Caco-2 cells by inducing cell cycle arrest and apoptosis.
  • The mechanism involves mitochondrial dysfunction and activation of the caspase pathway.
  • These findings suggest broader anti-tumor potential for ramucirumab beyond its anti-angiogenic properties.

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