SHARPIN Promotes TAK1 Expression And Activates JNKs Pathway In Mycosis Fungoides Progression

BackgroundSHARPIN ubiquitously expresses in multiple human tissues.SHARPIN subcellularly localizes in cytoplasm of cells,as well as in nucleus.Recently study showed that SHARPIN involves in the initiation and development of a variety of cancers.The etiology and pathogenesis of MF are elusive.Patients of patch or plaque stage of MF have an expectation of normal life,while patients of advanced stage,extensive and refractory MF experience a poor prognosis.It is important to probe the pathogenesis of MF for monitoring MF progression and improving the therapeutic effect of advanced MF.SHARPIN takes part in multiple tumors pathogenesis,however,role of SHARPIN in MF is unclear.JNKs play an oncogenic or anti-oncogenic role in cancers,whereas the role of JNKs pathway in the pathogenesis of MF remains largely unknown.The effect of SHARPIN on J-NKs pathway remains ambiguous.Objectives1.To probe SHARPIN expression and expression related progression,prognosis in MF;2.To demonstrate the molecular mechanism of JNKs signaling pathway regulated by SHARPIN in MF.Methods1.We analyzed SHARPIN expression and expression related prognosis in MF by data mining in GEO.2.We also detected SHARPIN expression and the JNKs pathway activity of MyLa2059 and CD4+T cells.The constructed SHARPIN overexpression and knockdown lentiviral vector were transfected in MyLa2059 respectively.The effects of SHARPIN overexpression or knockdown on the proliferation,apoptosis,and motility of MyLa2059 were evaluated,change of the critical molecules of JNKs pathway were also detected.293T cells were transfected with the constructed SHARPIN expression plasmid and TAKI-Promoter-Luc plasmid in two groups as follows:SHARPIN expression plasmid+TAK1-Promo ter-Luc plasmid,TAK1-Promoter-Luc plasmid;Luciferase assay was conducted to evaluate whether SHARPIN transactivates TAK1 and activates JNK pathway.Results1.By data mining,we compared SHARPIN expression in MF samples containing gain of 8q24.3,which was observed in 36%of MF samples,with that of no gain of 8q24.3 using GEO datasets,and found that SHARPIN expression was significantly increased in MF samples with gain of 8q24.3;moreover,overexpression of SHARPIN induced by gain of 8q24.3 associated with lower disease-specific survival rate in MF.2.SHARPIN expression in MyLa2059 was higher relative to CD4+T cells,constitutive activity of JNKs pathway was observed in MyLa2059.Compared to untransfected MyLa2059,transfected with SHARPIN overexpression lentiviral vector promoted proliferation,inhibited apoptosis,accelerated migration and invasion of MyLa2059,while transfected with SHARPIN knockdown lentiviral vector exhibited an opposite phenomena.Compared to untransfected MyLa2059,transfected with SHARPIN overexpression lentiviral vector showed an upregulated mRNA and protein expression of TAK1,JNK1,JNK2,p-JNK1,p-JNK2 and c-Jun,p-c-Jun.while transfected with SHARPIN knockdown lentiviral vector exhibited an opposite phenomena.Moreover,Luciferase assay showed that 293T cells transfected with SHARPIN expression plasmid+TAK1-Promoter-Luc plasmid exhibited a significantly higher luciferase value than only transfected with TAK1-Promoter-Luc plasmid.Conclusions1.The mRNA and protein expression of SHARPIN are upregulated in MF,which is related with a poor prognosis of MF;2.SHARPIN overexpression is positively associated with MF malignant phenotype by transactivating TAK1 and activating JNKs pathway sequentially.3.These findings may provide a potential biomarker for monitoring MF progression,predicting prognosis and a therapeutical target of MF.