DNA-PKcs and HIF-1α have also been shown to work in combination with MEK/ERK signalling to impart RR in glioblastoma cells, with a reduction in MEK/ERK leading to a reduction in HIF-1α accumulation and activity, and a downregulation of HIF-1α induced by inhibition of DNA-PKcs, leading to radiosensitisation106. The gene discussed is HIF1A; the disease is glioblastoma.