[Increased amounts of IL-10 mRNA in anaplastic astrocytomas and glioblastoma multiforme].

Interleukin 10 (Il-10) was initially discovered on the basis of its ability to suppress cytokine synthesis. Additionally, it can exert immunosuppressive effects on a variety of cell types. Since patients with malignant gliomas present with a general impairment of the immune system, we sought to investigate if IL-10 is expressed in the glioma tissue. Using RT-PCR, IL-10 mRNA levels were determined in 37 glial tumors of different grades including 2 recurrencies, 3 specimens from normal brain tissue and 3 glioblastoma cell lines. Expression of IL-10 mRNA was demonstrable in all tumors as well as in normal brain. High grade tumors and recurrent cases expressed significantly higher amounts of IL-10 specific mRNA compared to low grade tumors, while 2 out of 3 cell lines showed only weak constitutive expression. We suggest, that IL-10 may contribute to the progression of astrocytomas by allowing the tumor cells to attenuate the T-cell immune response and evade immune detection.