The origin of GIST is the Cajal cell which is found in many types of smooth muscle tissue.
GIST originates from the Cajal cells, a group of cells which control gut motility.
1.: C-kit (CD117) positive-stained mast cells (white arrow) and Cajal cell with cytoplasmic extension between muscle fibres from a control patient (black arrow; CD117, 400x).
The finding that Cajal cells express c-kit (CD117), a tyrosine kinase, is a considerable development.
Ten large magnification areas were counted in the same specimen from each case, and the number of Cajal cells was quantitatively determined.
It was determined that the Cajal cells were encountered more frequently in the control group.
Gastrointestinal stromal tumors (GISTs) are mesenchymal tumors that express type 3 tyrosine kinase receptors and are thought to develop from the neoplastic transformation of the interstitial Cajal cells (intestinal pacemaker cells on the intestinal wall) or their precursors (1-3).
Extraintestinal GISTs develop from multipotent stem cells, which are the precursors of the interstitial Cajal cells. Immunohistochemical studies have shown that they are CD117-positive, and according to a previous study, they constitute 10% of all GISTs (17).
Gastrointestinal stromal tumours are mesenchymal tumours of the digestive tract that originate from intestinal cajal cells and account for 0.1-3% of all gastrointestinal tumours.
In the gastrointestinal tract, CD 117-positive cells (Interstitial Cajal cells) are autonomic nerve-related gastrointestinal pacemaker cells that regulate intestinal motility.
This hypothesis is based in the ultrastructural similarities of GIST and Cajal cells
. Both types of cells express the CD 117 protein, but Cajal cells
do not stain for CD 34 nor for other muscle cell antigens frequently seen in GIST cells.
are located in the muscle layer of the gastrointestinal tract as the pacemaker cells of the gastrointestinal tract and commonly express c-kit proteins (CD117), myeloid stem cell antigen (CD34), and vimentin.