Magmas inhibits apoptosis in rat pituitary adenoma cell lines by impairing caspase activation

Program: Abstracts - Orals, Featured Poster Presentations, and Posters
Session: SAT 164-196-Pituitary
Basic/Clinical
Saturday, June 15, 2013: 1:45 PM-3:45 PM
Expo Halls ABC (Moscone Center)

Poster Board SAT-186
Maria Chiara Zatelli*1, Federico Tagliati2, Teresa Gagliano1 and Ettore Ciro degli Uberti1
1University of Ferrara, Ferrara, Italy, 2University of Ferrara, FERRARA, Italy
Magmas (mitochondria-associated protein involved in granulocyte-macrophage colony-stimulating factor signal transduction) is a nuclear gene that encodes for the mitochondrial import inner membrane translocase subunit Tim16. Magmas is overexpressed in the majority of human pituitary adenomas and in a mouse ACTH-secreting pituitary adenoma cell line. We here report that Magmas is highly expressed in two out of four rat pituitary adenoma cell lines and its expression levels inversely correlate to the extent of cellular response to pro-apoptotic stimuli (Starosporine) in terms of apoptosis activation and cell viability. Magmas overexpression in GH4C1 cells (GH4C1-M-DD cells) leads to an increase in cell viability and to a reduction in Staurosporine-induced apoptosis and DNA fragmentation, in parallel with the increase in Magmas protein expression. In addition, Staurosporine-induced translocation of cytochrome c from mitochondria to cytoplasm is greatly reduced in GH4C1-M-DD cells, where also caspase 9 and 3 activation is reduced. These results indicate that Magmas plays a pivotal role in mitochondrial cytochrome c release in response to pro-apoptotic stimuli and confirm and extend the finding that Magmas protects pituitary cells from apoptosis, suggesting its possible involvement in pituitary adenoma pathogenesis

Nothing to Disclose: MCZ, FT, TG, ECD

*Please take note of The Endocrine Society's News Embargo Policy at http://www.endo-society.org/endo2013/media.cfm