Expression of girdersofactin filaments (Girdin) in pituitary adenomasand its role in promoting cell proliferation / 第二军医大学学报

ABSTRACT

Objective To investigate the expression of girders of actin filaments (Girdin) in pituitary adenomas, and its role in promoting cell proliferation and the related molecular mechanism. Methods Two prolactinoma, growth hormone adenoma and non-functioning pituitary adenoma tissues, and one normal pituitary gland tissue were collected. The protein expression of Girdin in the different tissues was detected by Western blotting, and then the expression of Girdin was further confirmed by immunofluorescence. Rat pituitary tumor cell lines GH3 cell model with Girdin knockdown and overexpression was established by RNA interference and overexpression of Girdin, respectively. The protein expression of Girdin and Akt and phosphorylation level of Akt in the GH3 cell models were detected by Western blotting. The function and biological behavior of Girdin in pituitary adenomas tissues were studied by cell proliferation assay and cell apoptosis assay. Results The expression of Girdin in the non-functioning pituitary adenomas was the highest, followed by growth hormone pituitary adenomas. The high expression of Girdin in the non-functioning pituitary adenomas was also verified by immunofluorescence assay. RNA interference and overexpression of Girdin effectively knocked down and increased the expression of Girdin, respectively, accompanied by the simultaneous changes of Akt phosphorylation. In addition, overexpression of Girdin promoted the proliferation of GH3 cells. Conclusion Girdin is highly expressed in non-functioning pituitary adenomas and can promote the proliferation of pituitary adenoma cell by regulating the Akt phosphorylation.