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TRANSCRIPT
ROLE OF HER2 IN THE BREAST CANCER
Presented by:
Ayesha AyubTrainee Technologist
OUTLINE:
Introduction Gene HER2 Gene Diagnostic Test Treatment Conclusion
What is GENE ?
Genes are segments of DNA located on chromosomes.
Genes contain the codes for the production of specific proteins.
HER2 Gene ? HER2 stands for Human
Epidermal growth factor Receptor 2.
It is present on chromosome no 17.
HER2 is a protein on the surface of all normal cells in your body.
HER2 helps regulate the way cells grow and divide into other cells.
NORMAL HER2 vs CANCEROUS HER2
YES ! Normal Cells have HER2 Gene !
The difference is: Receptor over expression Dysregulation of receptor activation.
Diagnostic Tests
There are two tests for the detection of HER2 gene:
IHC TEST( immunohistochemistry) FISH Testing( fluorescence in situ hybridization)
Tests are usually performed on biopsy samples obtained by either fine-needle aspiration, core needle biopsy, vacuum-assisted breast biopsy, or surgical excision.
IMMUNOHISTOCHEMISTRY
It’s a prognostic test. IHC is a protein-based test that is used to
provide an assessment of the amount of HER2 protein receptors on the surface of the cancer cells.
IHC is the most commonly used test to see if a tumor has too much of the HER2 receptor protein on the surface of the cancer cells.
Scoring for an IHC from 0 to 3+.
INTERPRETATIONS OF IMMUNOHISTOCHEMISTRY
FISH TESTING FISH is a gene-based test used to determine the
number of HER2 genes in the cells of the tumor. In HER2-positive breast cancer if there are too many copies of the HER2 gene, the gene is “amplified."
This test can be used to visualize specific genes or portions of genes.
FISH is considered more accurate than IHC.
INTERPRETATION
OF
FISH
NEGATIVE HER2 AMPLIFICATION:
Treatment
There are some treatments available specifically for HER2-positive breast cancer.
The most commonly used medication is Herceptin (chemical name: trastuzumab), which works by attaching itself to the HER2 receptors on breast cancer cells and blocking them from receiving growth signals.
By blocking these signals, Herceptin may help to slow or even stop the growth of the breast cancer.
In addition to blocking HER2 receptors, Herceptin can also help fight breast cancer by alerting the immune system to destroy cancer cells onto which it is attached.
Mode Of Action
Conclusion
HER2-positive breast cancer is a breast cancer that tests positive for human epidermal growth factor receptor 2 (HER2), which promotes the growth of cancer cells.
In about 1 of every 5 breast cancers, the cancer cells make an excess of HER2 due to a gene mutation. This is a gene mutation that occurs only in the cancer cells and is not a type of mutation that you can inherit from a parent.
HER2-positive breast cancers tend to be more aggressive than other types of breast cancer.
They're also less responsive to hormone treatment. However, treatments that specifically target HER2 are very effective.
