SERPINE1 and pilocytic astrocytoma: Previous analysis of TCGA genomic data has shown high SERPINE1 expression in many GBMs and a correlation between expression level and overall survival.26SERPINE1 expression is also significantly different between the circumscribed grade I pilocytic astrocytoma and grade IV GBM.27SERPINE1 has diverse previously described roles including a possible function in immunomodulation26 and growth factor degradation.28 Here we show a non-canonical role in enhancing the invasive ability of GBM cells, but with no effect on cellular proliferation.