CTSD and neoplasm: AGR2 also induces tumor metastasis by regulating mTOR complex 2 (mTORC2) pathway (46), promotes tumor cell dissemination through post transcriptional activation of cathepsin B (CTSB) and D (CTSD) (14), and prevents the activation of transforming growth factors β (TGF- β), which is involved in epithelial mesenchymal transition (EMT) during tumor invasion and metastasis, in order to maintain the epithelial phenotype (47).