Neutrophil Gelatinase-Associated Lipocalin (NGAL) is a lipocalin that is well known for its functions as a shuttle for iron and siderophores, which comprises a critical component of innate immunity to exogenous bacterial infections. However, several lines of recent evidence have added new dimensions of functionality that have attracted the interest of cancer biologists and oncologists. This review will highlight the exciting new paths and roles that are emerging for NGAL in human cancers, in the tissue response to anticancer therapy, and in the acute kidney injuries that commonly complicate the care of patients with cancer. The evidence for NGAL induction and its role in various human cancers will be explored. The current status of NGAL as a predictive non-invasive biomarker of acute kidney injuries will also be examined.