FISH for N-myc Oncogene Amplification

Fluorescence in situ hybridization (FISH) for N-myc oncogene amplification is a molecular diagnostic test employed to detect the amplification of the N-myc oncogene in cells. The N-myc oncogene is a gene that can contribute to the transformation of a cell into a cancer cell when it is over-expressed or amplified. Amplification of the N-myc oncogene is associated with several types of cancer, most notably neuroblastoma.

The N-myc oncogene belongs to the Myc family of genes, which are known to be involved in the regulation of cell proliferation, differentiation, and apoptosis. Amplification of N-myc is an abnormality in which there are multiple copies of the gene. This is often associated with an aggressive tumor phenotype, and has been shown to have prognostic significance especially in neuroblastoma.

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• Test NameFISH for N-myc Oncogene Amplification
• Sample TypeParaffin embedded tissue blocks
• Preparations RequiredNo special preparation is needed for this test.
• Report Time7 days

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Neuroblastoma is a cancer that develops from immature nerve cells and most commonly affects children. The amplification of the N-myc oncogene is found in approximately 20-25% of neuroblastoma cases and is associated with advanced-stage disease, rapid tumor progression, and poor prognosis.

In the FISH test for N-myc amplification, a sample of blood, bone marrow, or tissue is obtained from the patient. This sample is then fixed on slides, and the DNA is denatured so that it can hybridize with fluorescently labeled probes that are specific to the N-myc gene.

The probes will bind to the regions of the DNA where the N-myc gene is located. Under a fluorescence microscope, the bound probes can be seen as fluorescent signals. In normal cells, there are generally two signals representing the two copies of the N-myc gene. However, in cells with N-myc amplification, multiple signals are seen due to the additional copies of the gene.

The amplification of the N-myc oncogene is considered a high-risk factor in neuroblastoma. Patients with this genetic alteration often have a more aggressive form of the disease, which is more difficult to treat. The presence of N-myc amplification can influence treatment decisions, as high-risk patients may require more aggressive therapy.

Besides neuroblastoma, N-myc amplification has also been observed in other malignancies, such as small cell lung cancer, retinoblastoma, and some brain tumors, although less frequently.

Treatment for cancers with N-myc amplification varies depending on the type and stage of the cancer. For neuroblastoma, a multimodal approach is often used, including chemotherapy, surgery, radiation therapy, stem cell transplant, and targeted therapies.

There is ongoing research on targeted therapies that specifically inhibit the N-myc oncogene. These therapies aim to block the action of the N-myc protein and thus reduce the proliferation of cancer cells.