KIT and its ligand stem cell factor are widely expressed in embryonic and adult mouse brain, and they play a role in many signal transduction pathways involved in cellular proliferation, differentiation and cancer cell metastasis.
KIT, PDGFRA, NF1 and SDH mutations are alternate initiating events, fostering hyperplasia in gastrointestinal stromal tumours (GISTs), and additional genetic alterations are required for progression to malignancy.
A proto-oncogene c-kit, which encodes a transmembrane tyrosine kinase, is overexpressed in some malignancies, including small-cell lung cancer (SCLC), and is thought to be involved in their pathogenesis.
Activating mutations in KIT play an important role in diagnosis and prognosis of multiple malignancies including mastocytosis, gastrointestinal stromal tumors, and a subset of melanoma and acute myeloid leukemia.
After analyzing the RNA-Seq data of PTC patients from the Cancer Genomic Atlas, 497 differentially expressed PTC genes were found to be associated with HT, of which protein tyrosine phosphatase receptor type C (PTPRC), KIT, and COL1A1 were associated with tumor size and lymph node metastasis (p < 0.05).
All 17 cases with either mutated KIT (n = 15) or PDGFRA (n = 2) were histologically GIST tumors, whereas none of the other histologic types of cancer (n = 316) harbored KIT or PDGFRA mutation.
Although activating KIT mutations are present in approximately 20% of canine MCTs, molecular etiology is largely unknown for the majority of this cancer.
An <i>in vitro</i> study reportedly revealed that CD117-positive cell populations in NSCLC cell lines exhibited cancer stem cell (CSC) phenotypes including self-renewal and chemoresistance.
Because other KIT-expressing malignancies might benefit from Imatinib therapy, we evaluated the distribution and expression of KIT in 1166 cases of malignant lymphoma.
Blockade of KIT and the downstream signaling cascade at various levels results in inhibition of Merkel cell carcinoma growth in vitro, suggesting targets for therapy of this cancer.
BRAF mutations represent an alternative molecular pathway in the early tumorigenesis of a subset of KIT/PDGFRA wild-type GISTs and are per se not associated with a high risk of malignancy.
Cabozantinib, a tyrosine kinase inhibitor of FMS-like tyrosine kinase 3 (FLT3), MET, AXL, vascular endothelial growth factor receptor, and KIT, is approved for use in multiple malignancies.