PDCD4 and head and neck squamous cell carcinoma: In particular, vesicular miR21, upregulated under hypoxia in oral squamous cell carcinoma cells [84] and in head and neck squamous cell carcinoma (HNSCC) cells [114] in HIF-1α and HIF-2α–dependent ways, was reported to be able to downregulate a pool of genes (PDCD4, PTEN, E-Cadherin) and induce EMT of the target normoxic cells, while miR-1273f, upregulated by hypoxia in EVs derived from hepatocellular carcinoma cells (HCC), promotes proliferation, migration, EMT and invasiveness in normoxic cells by targeting LHX6 and subsequently activating Wnt/β-catenin signaling pathway [112].