[Study on the origin and differentiation of gastrointestinal stromal tumors].
OBJECTIVE
To explore the origin and differentiation of gastrointestinal stromal tumors (GISTs).


METHODS
Immunohistochemistry staining and electron microscopy were adopted.


RESULTS
In 212 cases of primary GISTs, the positive rates of CD117, CD34, alpha-SMA, MSA, desmin, S-100, PGP9.5 were 96.7%, 77.3%, 19.3%, 15.6%, 1.9%, 16.3%, and 12.3% respectively. Among them, GISTs showed a diffuse and strong positivity for CD117. Electron microscopy of tumor cells demonstrated numerous mitochondria, prominent perinuclear Golgi complex, smooth and rough endoplasmical reticulum and intermediate filaments. Irregular caveolae, dense plaque, incontinuous basal lamina were observed occasionally. Cytoplasmic processes were often observed accompanying with local adhesion present between the processes or between the processes and the cell membrane.


CONCLUSIONS
Data from both immunophenotype and electron microscopy suggest that GIST might originate from the mesenchymal cells, differentiating to be ICC afterwards, and possessing myoid characteristics in various extent.
Hou
Ying-yong
YY
Department of Pathology, Cancer Hospital, Medical College of Fudan University, Shanghai 200032, China.
Zhu
Xiong-zeng
XZ
Wang
Jian
J
Tan
Yun-shan
YS
Sun
Meng-hong
MH
Du
Xiang
X
Shi
Da-ren
DR
D002454:Cell Differentiation; D046152:Gastrointestinal Stromal Tumors / Q000737:chemistry / Q000648:ultrastructure*; D006056:Golgi Apparatus / Q000648:ultrastructure; D006801:Humans; D007150:Immunohistochemistry; D008854:Microscopy, Electron; D019009:Proto-Oncogene Proteins c-kit / Q000032:analysis*; D009418:S100 Proteins / Q000032:analysis*; D017154:Stromal Cells / Q000737:chemistry / Q000648:ultrastructure; D043222:Ubiquitin Thiolesterase / Q000032:analysis
D009418:S100 Proteins; C482860:UCHL1 protein, human; D019009:Proto-Oncogene Proteins c-kit; D043222:Ubiquitin Thiolesterase