Activation Status and Biological Effects Analysis of STAT3 Signaling Pathway and Its Negative Regulator PIAS3 in Gliomas / 中国医科大学学报

ABSTRACT

Objective To discuss the activation and biological effects of STAT3 signaling pathway and its negative regulator PIAS3 in glioma cells. Methods Immunohistochemistry(IHC)was used to test the expression of p?STAT3 and PIAS3 in gliomas. AG490(60μmol/L),the in?hibitor of STAT3 signaling pathway,was used to treat U118 and U87 cells for 24/48 h,and the method of MTT assay was taken to evaluate the pro?liferation after AG490 treatment. The expression of p?STAT3 and PIAS3 was also examined by immunofluorescence(IF). Results There was no obvious significance between p?STAT3 and PIAS3 in nuclei or cytoplasm at different grades of gliomas. Whereas,p?STAT3 and PIAS3 were nega?tively correlated in the nuclei of vary grades malignancy gliomas. After AG490 treatment,U118 cells showed no obvious quantitative changes. How?ever,U87 cells showed obvious growth inhibition. IF results showed that there was no significant change at the levels of p?STAT3 and PIAS3 after AG490 treatment in U118 cells. However,the expression of p?STAT3 in the nuclei was down?regulated,and PIAS3 showed obvious nuclear translo?cation in U87 cells. Conclusion Nuclear translocation of PIAS3 plays the key role in modulating JAK/STAT signaling activation and inhibiting glioma cells proliferation.