The LNK adaptor protein: a dual regulator of proliferation and migration in solid tumors

Cancer is a significant public health problem. Alterations in critical cellular responses, such as proliferation, survival, and migration, are hallmarks of cancer. Deregulation of the JAK/STAT, MAPK, and PI3K/AKT signaling pathways has been implicated in the development of most solid cancers; therefore, their strict control is a primary research focus. The LNK adaptor protein is a key negative regulator of these pathways in normal cells and in certain hematological malignancies, where it regulates the proliferation, migration, and inflammatory response of different cell types. However, the function of LNK in solid tumors is less clear. Recent evidence suggests that LNK inhibits proliferation and migration in some types of solid tumors but activates these same processes in others. In this review, we provide an overview of the essential functions of LNK in healthy tissues, compare these functions with LNK's reported activities in solid tumors, and discuss the potential mechanisms involved in the dual actions of the LNK protein.