Anterior gradient 2 protein belongs to a family of chaperone-like proteins, namely protein disulfide isomerase. Human anterior gradient-2 (AGR2), a member of protein disulfide isomerase (PDI) family, is present in both intracellular and extracellular compartments. Generally, AGR2 is highly expressed in mucus-secreting cells and endocrine organs, the expression profile of AGR2 and cell cycle proteins here presented was showed as good prognosis marker in epithelial ovarian cancer. Increased levels of extracellular AGR2 (eAGR2) have been correlated with poor prognosis in cancer patients, making it a potential biomarker. Pathway analyses suggested that increased AGR2 was associated with endoplasmic reticular homeostasis, possibly allowing tumor cells to overcome hypoxic stress and meet the increased protein demand of tumorigenesis, thereby preventing unfolded protein response-mediated apoptosis. AGR2 is a well-studied secreted protein that is involved in multiple biological processes including cell proliferation and migration. Anterior Gradient 2 (AGR2) is a protein expressed in many solid tumor types including prostate, pancreatic, breast and lung. AGR2 functions as a protein disulfide isomerase in the endoplasmic reticulum.