Versican is a large chondroitin sulphate proteoglycan produced by several tumour cell types, including high-grade glioma. The increased expression of certain versican isoforms in the extracellular matrix (ECM) plays a role in tumour cell growth, adhesion and migration. Transforming growth factor-b2 (TGF-b2) is an important modulator of glioma invasion, partially by remodeling the ECM. However, it is unknown whether it interacts with versican during malignant progression of glioma cells. Here, we analysed the effect of TGF-b2 on the expression of versican isoforms. The expression of versican V0/V1 was upregulated by TGF-b2 detected by quantitative polymerase chain reaction and immunoprecipitation, whereas V2 was not induced. Using time-lapse scratch and spheroid migration assays, we observed that the glioma migration rate is significantly increased by exogenous TGF-b2 and inhibited by TGF-b2-specific antisense oligonucleotides. Interestingly, an antibody specific for the DPEAAE region of glycosaminoglycan-b domain of versican was able to reverse the effect of TGF-b2 on glioma migration in a dose-dependent manner. Taken together, we report here that TGF-b2 triggers the malignant phenotype of high-grade gliomas by induction of migration, and that this effect is, at least in part, mediated by versican V0/V1.

In our series, Tenascin-C and TGF-beta1 were expressed in the vast majority of high-grade gliomas. We could not detect a correlation of one of the proteins with time to progression. Nevertheless, we describe induction of Tenascin-C by TGF-beta1, possibly providing a mechanism for the invasion of high-grade gliomas into healthy parenchyma.

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