Translocation t(7;17)(p15;q21) is one of the most commonly occurring molecular markers of endometrial stromal tumors.
Translocation includes JAZF1 gene localized on the chromosome 7 and JJAZ1 gene (joined to JAZF1) (also SUZ12) located on chromosome 17. These genes belong to the "zinc-finger" family of transcription factors. JJAZ1 is also a member of "polycomb group" (PcG) family of proteins, with which it forms complexes that negatively regulate the expression of homeotic genes during embryogenesis. JAZF1 gene function is still unclear, however it is known that it encodes a transcriptional co-repressor, which binds to the "orphan" nuclear receptor TAK1.
In the chimeric gene, the N-terminal "zinc-finger" domain of JAZF1 gene with "zinc-finger" domains connects with the domain giving a signal to nuclear localization of JJAZ1 gene. The exact mechanism by which this gene product works in tumor transformation is not known.
To detect the translocation of t(7;17)(p15;q21), we use one-round RT-PCR (Fig. 1) followed by verification of the fusion product using a direct sequencing (Fig. 2).
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