Herceptin, a recombinant humanized anti-ERBB2 monoclonal antibody, induces cardiomyocyte death

Area of Science:

• Oncology
• Cardiology
• Molecular Biology

Background:

• Trastuzumab is an effective anti-cancer therapy targeting ERBB2/HER2.
• Adverse cardiac events are a known side effect of trastuzumab treatment.

Purpose of the Study:

• To investigate the molecular mechanisms underlying trastuzumab-induced cardiac dysfunction.
• To explore the role of the MDM2/p53 axis in trastuzumab's cardiotoxic effects.

Main Methods:

• Assessing p53 protein levels and apoptosis markers in response to trastuzumab.
• Investigating the interaction between trastuzumab, ERBB2, and MDM2.
• Evaluating the involvement of ERK1/2 and Akt signaling pathways.

Main Results:

• Trastuzumab treatment elevated p53 protein levels and increased apoptosis, evidenced by higher cleaved caspase-3.
• Cardiac function was diminished in conjunction with elevated p53.
• MDM2 was identified as a potential regulatory target of anti-ERBB2 antibodies, implicating the MDM2/p53 axis in cardiac outcomes.
• These MDM2/p53-mediated events were independent of ERK1/2 and Akt signaling.

Conclusions:

• Adverse cardiac events associated with trastuzumab may result from impaired p53 degradation due to negative regulation of MDM2.
• This impairment promotes apoptosis and leads to cardiac dysfunction.
• Targeting the MDM2/p53 pathway could offer therapeutic strategies to mitigate cardiotoxicity during anti-cancer treatment.