What does trastuzumab do to HER2?

Herceptin works by blocking the effects of HER2 and encouraging the immune system (the body’s natural defences) to attack and kill the cancer cells.

What does HER2 low mean?

HER2-low is defined as IHC 1+ or IHC 2+ without HER2 gene amplification and compromises about 50 to 55% of all primary breast cancers [3, 4].

What is HER2 overexpression?

All these extra HER2 genes tell breast cells to make too many HER2 receptors (HER2 protein overexpression). This makes breast cells grow and divide in an uncontrolled way. Advertisement. Breast cancers with HER2 gene amplification or HER2 protein overexpression are called HER2-positive in the pathology report.

What is the mechanism of trastuzumab?

Mechanism of Action of Trastuzumab Trastuzumab consists of two antigen-specific sites that bind to the juxtamembrane portion of the extracellular domain of the HER2 receptor and that prevent the activation of its intracellular tyrosine kinase. The remainder of the antibody is human IgG with a conserved Fc portion.

Is HER2-negative metastatic?

When you have HER2-negative advanced (metastatic) breast cancer, treatment usually focuses on managing your disease, not curing the cancer. The goal is to help you live longer and have a better quality of life. This type of cancer is most often treated with systemic therapy.

What is HER2 heterogeneity?

HER2 heterogeneity was defined as either the presence of HER2 positivity in between 5% and 50% of tumor cells or the presence of an area of tumor testing HER2-negative.

What does hr2 negative mean?

When a breast cancer is HER2-negative, it means that the cancerous cells do not contain high levels of the protein HER2. There are many treatment options available for this type of breast cancer, but the outlook can vary.

Is HER2-negative better than positive?

Breast cancer cells with higher than normal levels of HER2 are called HER2-positive. These cancers tend to grow and spread faster than breast cancers that are HER2-negative, but are much more likely to respond to treatment with drugs that target the HER2 protein.

What is the MOA of trastuzumab?

As an antibody, one of the major mechanisms of trastuzumab is to attract immune cells to tumor sites that overexpress HER2, by a mechanism called antibody-dependent cellular cytotoxicity (ADCC).

What is trastuzumab target?

Herceptin (chemical name: trastuzumab) is a HER2 inhibitor targeted therapy. Herceptin works against HER2-positive breast cancers by blocking the ability of the cancer cells to receive chemical signals that tell the cells to grow.