PRKN and glioblastoma: Furthermore, in order to explore the possible mechanism of the effect of HSD11B1L-181 on GBM, we screened the human GBM cDNA expression library by yeast two-hybrid, and confirmed that E3 ubiquitin ligase parkin is a specificity target of HSD11B1L-181 by additional co-immunoprecipitation and immunofluorescence staining.