STC2 and gastric cancer: Thioredoxin domain-containing protein 12 (TXNDC12), a member of the protein disulfide isomerase (PDI) family, is implicated in the tumorigenicity of human gastric cancer [29] STC2, also known as Stanniocalcin 2, is a secreted glycoprotein that exhibits significant transcriptional and post-transcriptional regulation under a variety of stress conditions, such as ER stress, hypoxia, and nutrient deprivation.