The IGH/MAF Plus v2 Translocation, Dual Fusion Probe consists of the IGH probe mix, labelled in green, proximal to the Constant and within the Variable segment of the IGH region and the MAF probe mix, labelled in red, that encompasses the MAF gene and flanking regions as well as the WWOX gene.
MAF (MAF bZIP transcription factor) gene is located at 16q23 and IGH (immunoglobulin heavy locus) at 14q32.3. Approximately 50-60% of multiple myeloma (MM) cases are associated with translocations involving IGH and one of several partners including CCND1, NSD2 (WHSC1) and FGFR3, CCND3, MAF or MAFB1. The t(14;16)(q32.3;q23) translocation is a recurrent translocation seen in 2-10% of MMs1.
The majority of the breakpoints occur within the last intron of WWOX (WW domain containing oxidoreductase), centromeric to MAF. These breakpoints have a dual impact of positioning the IGH enhancer near MAF and disrupting the WWOX gene2. Gene expression profiling of myeloma cell lines revealed that MAF caused transactivation of cyclin D2 (a promoter of cell cycle progression), thus enhancing proliferation of myeloma cells3.
According to the literature, MM patients harbouring the t(14;16) appear to have a more aggressive clinical outcome4,5.
The CytoCell® IGH/MAF Plus v2 Translocation, Dual Fusion Probe is a qualitative, non-automated, fluorescence in situ hybridisation (FISH) test used to detect chromosomal rearrangements between the 14q32.3 region on chromosome 14 and the 16q23 region on chromosome 16 in Carnoy’s solution (3:1 methanol/acetic acid) fixed haematologically-derived cell suspensions from patients with confirmed or suspected multiple myeloma (MM).
This device is designed as an adjunct to other clinical and histopathological tests in recognised diagnostic and clinical care pathways, where knowledge of IGH::MAF translocation status would be important for clinical management.
This device is designed to detect rearrangements with breakpoints in the region covered by the red and green clones in this probe set, which includes the IGH and MAF regions. Breakpoints outside of this region, or variant rearrangements wholly contained within this region, may not be detected with this device.
This device is not intended for: use as a stand-alone diagnostic, use as a companion diagnostic, prenatal testing, population-based screening, near-patient testing, or self-testing.
This device has not been validated for sample types, disease types, or purposes outside of those stated in the intended purpose.
It is intended as an adjunct to other diagnostic laboratory tests and therapeutic action should not be initiated on the basis of the FISH result alone.
Reporting and interpretation of FISH results should be performed by suitably qualified staff, consistent with professional standards of practice, and should take into consideration other relevant test results, clinical and diagnostic information.
This device is intended for laboratory professional use only.
Failure to adhere to the protocol may affect the performance and lead to false positive/negative results.
We have successfully used CytoCell haematology probes over the last 5 years and were looking for the same quality and consistency for our FISH pathology screening. OGT worked closely with us to help our lab evaluate – and later validate – CytoCell pathology probes. CytoCell is now our primary FISH probe supplier. Results have been excellent and we were able to consolidate our workflow to follow a single, streamlined protocol.
Dr Mary Nordberg
Molecular Pathology Director, Delta Pathology Group, USA