IL6 and esophageal squamous cell carcinoma: For example; in esophageal squamous cell carcinoma abrogation of JAK-STAT3 signaling downregulates NF-κB signaling, in head and neck squamous cell carcinoma interfering with NF-κB reduced STAT3 signaling and in brain pericytes STAT3 cooperates with NF-κB to induce IL-6 production (38–40).