Neutrophil Gelatinase-Associated Lipocalin (NGAL): A Promising Biomarker for Cancer Diagnosis and A Potential Target for Cancer Therapeutics

NGAL, also known as lipocalin-2, is a secretory glycoprotein encoded by LCN2 gene and found to be expressed majorly in kidney diseases. In recent years, NGAL is procuring enormous attention as a cancer biomarker with its differential expression pattern. In breast cancer, NGAL binds with MMP9 and promotes invasion. High expression of NGAL is strongly involved in the progression of colorectal cancer, esophageal cancer, chronic myeloid leukemia, hepatocellular carcinoma, gastric and endometrial cancers. However, in other cancers such as pancreatic cancer and oral cancer, downregulation of NGAL leads to disease progression. Interestingly, a cell surface receptor for NGAL, NGALR was identified and the co-expression of both NGAL and NGALR has been implicated in different cancers. Therefore, understanding the function of NGAL in the development of cancer would provide us new insights to cancer development. This would also help us to develop biomarkers for cancer diagnosis and prognosis. This review article discusses the role of NGAL and NGALR in malignant diseases.