Autophagy and tumor cell dormancy in head and neck cancer

Educational Objective: At the conclusion of this presentation, the participants should be able to discuss the concepts of autophagy and tumor cell dormancy, and how these cellular processes may be targeted in order to prolong survival in patients with squamous cell carcinoma of the head and neck. Objective: (1) To explain the concept of tumor cell dormancy (2) To define the role of autophagy, which is a form of nutrient recycling, as a mechanism by which dormant tumor cells survive nutrient deprivation 3) To identify a molecular pathway responsible for the induction of autophagy. Study Design / Methods: In vivo laboratory study using the HEp3 cell line. Results: Dormant HEp3 (DHEp3) cells had a significantly higher baseline level of autophagy as compared to tumorigenic HEp3 (THEp3) cells. DHEp3 cells also had higher viability rates after treatment with chloroquine. Activation of pERK in THEp3 cells increased autophagy, while deactivation of pERK in DHEp3 cells decreased autophagy. Conclusion: Pharmacological inhibition of autophagy or the pERK pathway may prolong survival in patients with locally advanced head and neck cancer.