Generation of Heart Muscle Cells From Blood or Skin Cells of Breast Cancer Patients

Inclusion criteria

• Female
• Age greater than 18 years
• Willing to participate in protocol procedures with signed informed consent
• Assessment of LVEE via echocardiogram, cardiac MRI, or MUGA

Subjects in the cardiotoxicity group (TOX) must meet the following criteria:

• History of HER2 positive breast cancer (stage I-IV)
• Prior/current treatment with anthracycline based chemotherapy followed by anti-HER2 directed therapy or anti-HER2 directed therapy alone
• Assessment of LVEF at baseline prior to initiation of anthracycline or anti-HER2 therapy and during anti-HER2 therapy via echocardiogram, cardiac MRI, or MUGA
• Prior confirmed diagnosis of cardiotoxicity associated with anti-HER2 based therapy, defined as a decrease in LVEF > 10% from baseline to < 53% with symptoms of heart failure (NYHA class II-IV).

Subjects in the no cardiotoxicity group (NO-TOX) must meet the following criteria:

• History of HER2 positive breast cancer (stage I-IV)
• Completion of planned anthracycline and anti-HER2 therapy, or anti-HER2 therapy alone
• No symptoms of heart failure (NYHA class II-IV) during and at the end of anthracycline and anti-HER2 therapy
• Assessment of LVEF at baseline prior to innitiation of anthracycline or anti-HER2 therapy and during anti-HER2 therapy via echocardiogram, cardiac MRI, or MUGA
• Normal LVEF >53% at each assessment during and at the end of trastuzumab therapy.
• Maximum absolute decrease in LVEF <5% from baseline during and at the end of trastuzumab therapy.
• LVEF assessment performed at baseline and at least two time points during trastuzumab therapy.

Exclusion criteria

• Unwilling or unable to give skin biopsies
• Contraindications to punch biopsy including but not limited to bleeding diathesis, as determined by the investigator.
• Known pre-existing CV disease prior to initiation of breast cancer therapy as determined by the investigator, including

• Obstructive coronary artery disease (stenosis >70%)
• Arrhythmia - paroxysmal or persistent atrial arrhythmias, sustained ventricular tachycardia (>30 seconds), ventricular fibrillation, or cardiac arrest
• Cardiomyopathy (EF <53%)
• Heart failure (NYHA class II-IV)
• Valvular heart disease with equal to or greater than moderate stenosis or regurgitation