TrkA

Role in cancer

TrkA has a dual role in cancer. TrkA was originally cloned from a colon tumor; the cancer occurred via a translocation, which resulted in the activation of the TrkA kinase domain. Although originally identified as an oncogenic fusion in 1982, only recently has there been a renewed interest in the Trk family as it relates to its role in human cancers because of the identification of NTRK1 (TrkA), NTRK2 (TrkB) and NTRK3 (TrkC) gene fusions and other oncogenic alterations in a number of tumor types. The mechanism of activation of the Human Trk oncogene is suspected to involve a folding of its kinase domain, leading the receptor to remain constitutively active. In contrast, Trk A also has the potential to induce differentiation and spontaneous regression of cancer in infants.