Herstellung und Charakterisierung von Tetracyclin-induzierbaren, MIF-antisense-exprimierenden Glioma-Transfektanten

Immunohistochemical assays show a marked upregulation of the expression of macrophage migration inhibition protein (MIF) in glioblastoma cells. Here like in other tumor species MIF seems to play an important role in tumor growth, but the exact mechanism is yet unknown. For a better understanding of the MIF-function, an inducible gene expression system (Tet-On system) was established by double-stable transfection in different human and murine glioma cell lines (LN18, LN229, and RGL3 respectively). These transfectants produce MIF-antisense-RNA under the control of a tetracycline responsive promotor. The aim of this study was to inhibit the endogenous MIF protein expression by formation of RNA-RNA-hybrids. Although my data showed a clear increase of MIF-antisense-production in the observed transfectants after addition of doxycycline, the level of MIF protein in the cells remained constant. As a result I conclude that for this kind of tumor the combination of Tet-On system and antisense technique is not suitable to inhibit the MIF protein expression.