RUNX3 and oral cavity squamous cell carcinoma: Epigenetic silencing of human runt-related transcription factor 3 (Runx3) gene (tumor suppressor gene and integral components of TGF-β signaling) expression by promoter hypermethylation plays a critical role in gastric cancer [44], cholangiocarcinoma [45], oral squamous cell carcinoma [46], pancreatic cancer [47], esophageal squamous cell carcinoma [48] and hepatocellular carcinoma [49].