ALK

ALK is a tyrosine kinase receptor in a large family of insulin receptors that is normally expressed at low levels in the central and peripheral nervous systems. ALK can be activated in cancers through a variety of mechanisms, most commonly through chromosomal translocation to form fusion proteins, such as in anaplastic large cell lymphoma and inflammatory myofibroblastic tumors, and through amplification mutations, such as in neuroblastomas. Its abnormal expression is also found in various solid tumors and brain tumors, such as in non-small-cell lung cancer. ALK protein expression in tumor cells is a sign of good prognosis.