Next, cells were transfected with siRNA-HIF1A or siRNA-HIF2A.The results of RT-PCR and Western blot data showed that knockdown HIF1A could reduce the FTL expression, while inhibiting HIF2A had no effect on FTL expression (Fig. 2g-i).IF staining also confirmed that knockdown HIF1A in glioma cells decreased FTL expression (Figure S2C). Here, HIF1A is linked to central nervous system cancer.