Temozolomide induces autophagy in primary and established glioblastoma cells in an EGFR independent manner.

Despite major contributions to the current molecular understanding of autophagy, a recycling process for intracellular components to maintain homeostatic balance, relatively little is known about the interacting networks. To address this issue, the current study investigated the role of autophagy in primary and established glioblastoma multiforme (GBM) cells and its interplay with the epidermal growth factor receptor (EGFR) and the standard chemotherapeutic agent temozolomide (TMZ). TMZ treatment leads to an upregulation of autophagy, predominantly in primary GBM cells. The interaction between EGFR and Beclin-1, an important protein in initiating autophagy, was assessed using a cancer cell line transfected with EGFRvIII, and by stimulation with EGF. The results of the current study suggest that Beclin-1 and EGFR do not interact directly in either primary or established GBM cells. To enable the limited efficacy of patient treatment strategies of GBM to potentially be enhanced through the application of autophagy regulators, the multiple cellular interactions of autophagy require further elucidation.