Combining MYC and BCL2 testing by FISH (Fluorescence In Situ Hybridization) is a molecular diagnostic approach used to assess the genetic abnormalities in cancer cells, particularly in lymphomas and some types of solid tumors. This combined FISH analysis involves the evaluation of two different genes: MYC (c-Myc) and BCL2 (B-cell lymphoma 2), both of which are involved in cell growth and apoptosis regulation. Here’s how the combination of MYC and BCL2 testing by FISH typically works:
- Sample Collection: A tissue sample, often obtained through a biopsy or surgical procedure, is collected from the patient. This tissue sample contains cancer cells.
- Tissue Preparation: The collected tissue sample is processed and prepared for FISH analysis. This includes fixing the tissue and preparing thin sections on glass slides.
- FISH Probe Preparation: Specific DNA probes are designed to target the MYC gene region and the BCL2 gene region. These probes are labeled with distinct fluorescent molecules that emit different colors when exposed to specific wavelengths of light. The MYC probe is usually labeled with one color, while the BCL2 probe is labeled with another color
- Hybridization: The tissue sample is incubated with both the MYC and BCL2 DNA probes. If there are abnormalities in either the MYC or BCL2 genes, such as gene rearrangements or amplifications, the corresponding DNA probes will bind to the target sequences.
- Fluorescent Labeling: When the DNA probes bind to the target MYC and BCL2 gene sequences, they emit fluorescent signals in their respective colors.
- Imaging and Analysis: The tissue sample is examined under a fluorescent microscope, which can distinguish between the different fluorescent signals emitted by the MYC and BCL2 probes. The presence of altered patterns of fluorescence signals in either the MYC or BCL2 genes indicates genetic abnormalities, such as translocations, rearrangements, or amplifications.
The combined MYC and BCL2 FISH analysis is particularly important in the diagnosis and classification of various types of lymphomas, such as double-hit lymphomas. These lymphomas are characterized by concurrent MYC and BCL2 gene abnormalities and are associated with aggressive disease behavior.
In addition to diagnosis, this combined FISH analysis can help guide treatment decisions. For example, lymphomas with both MYC and BCL2 abnormalities may require more intensive therapies or different treatment approaches than lymphomas with a single gene abnormality.
As with other FISH tests, the interpretation of combined MYC and BCL2 FISH results should be conducted by experienced pathologists or oncologists who are familiar with the clinical context and guidelines for the specific cancer being evaluated. These results are often used in conjunction with other diagnostic and prognostic factors to tailor treatment plans for individual patients
