D-mannuronic acid (MA) is an important component of a natural polysaccharide alginate that can specifically bind to mannose receptor (MR) mostly expressed by macrophages, dendritic cells and endothelial cells, and MR is also found overexpressed in many cancer cells because of their higher affinity for carbohydrate molecules than that of normal cells due to higher demand for nutrients [112]. This evidence concerns the gene NR3C2 and cancer.