PADI4 and esophageal cancer: Our previous studies showed that PADI4 has a molecular weight of 67 kDa in esophageal cancer (Chang et al. 2011), 74 kDa in esophageal squamous cell carcinoma (Liu et al. 2019a), and 74 kDa (Chang et al. 2022) and 70 kDa in gastric cancer (Zheng et al. 2016a).