NAB2-STAT6

Extensive studies done on these tumours depicted that the majority of the SFT and HPC share NAB2 and STAT6 genes fusion, inversions at Chromosome 12q13. Other diagnostic markers that diagnose SFT may include Ki-67 labelling, MIB-1 labelling, CD34 and TFE3. In combination with STAT6, these markers can be used to identify SFT and differentiate them from other tumours. Clinical sequencing of the whole-exome and transcriptome of SFT patients revealed NAB2-STAT6 fusion to be the leading cause of this disease. The fusion between a transcriptional repressor (NAB2) and transcriptional activator (STAT6) initiates the transformation of a transcription repressor to the transcriptional activator and enhances EGF-induced promoter activity. Studies performed on mouse fibroblast cell line NIH-3T3 cells revealed that transfection of NAB2-STAT6 fusion gene enhances cell proliferation and migration in this cell line. Microarray analysis on Early growth response protein 1 (EGR-1) targeted genes: NAB1, NAB2, IGF2, FGF2, PDGFD, FGFR1, and NTRK1 were highly expressed in patients with recurrent SFT. Their expression was confirmed using Qualitative PCR (qPCR). Park.et.al (2020) identified the relationship between the NAB2-STAT6 fusion and PI3K/Akt pathway. The fusion gene induces the expression of the EGR-1 target gene IGF2 via the PI3K/Akt pathway [19]. IGF2 via PI3K/Akt signalling pathway has a role in cancer stem cell survival and cancer stemness [20]. This recent study on IGF2 and SFT suggests that IGF2 can also be used as a marker to identify SFT but further studies are required to suggest whether or not IGF2 can be used as a target to treat SFT.