PRKAA1 and glioblastoma: In addition, the co-immunoprecipitation (Co-IP) results in Additional file 4: Figure S4 supported that anti-PD-L1 especially pulled down AMPK in TR-GBM cells, compared to the TS-GBM cells, indicating that PD-L1 was prone to interact with AMPK in TR-GBM cells.