PDK1 and esophageal squamous cell carcinoma: miR-375 appears to play a tumor-suppressing role in HNC, as it has been shown to suppress cancer cell proliferation, migration, and invasion; this is possibly achieved by targeting XPR1 in esophageal squamous cell carcinoma (ESCC) [61], HNF1β in LSCC [65], as well as PDK1 [60] and USP1 [66] in nasopharyngeal carcinoma (NPC).