Fig. 2From: Endoplasmic reticulum stress promotes the release of exosomal PD-L1 from head and neck cancer cells and facilitates M2 macrophage polarizationThe activation of ER stress correlates with poor survival rates of OSCC patients. The Kaplan–Meier curves indicated significantly shorter overall survival for patients with an overexpression (n = 129) of PERK (A), ATF6 (B), and GRP78 (C) than for those with low expression levels (n = 320) (P = 0.01)Back to article page