title: Primary cilia in gastric gastrointestinal stromal tumours (GISTs): an ultrastructural study.
abstract: Gastrointestinal stromal tumours (GISTs) are the most common mesenchymal (non-epithelial) neoplasms of the human gastrointestinal (GI) tract. They are thought to derive from interstitial cells of Cajal (ICCs) or an ICC progenitor based on immunophenotypical and ultrastructural similarities. Because ICCs show primary cilium, our hypothesis is based on the possibility that some of these neoplastic cells could also present it. To determine this, an exhaustive ultrastructural study has been developed on four gastric GISTs. Previous studies had demonstrated considerable variability in tumour cells with two dominating phenotypes, spindly and epithelioid. In addition to these two types, we have found another cell type reminiscent of adult ICCs with a voluminous nucleus surrounded by narrow perinuclear cytoplasm with long slender cytoplasmic processes. We have also noted the presence of small undifferentiated cells. In this study, we report for the first time the presence of primary cilia (PCs) in spindle and epithelioid tumour cells, an ultrastructural feature we consider of special interest that has hitherto been ignored in the literature dealing with the ultrastructure of GISTs. We also point out the frequent occurrence of multivesicular bodies (MVBs). The ultrastructural findings described in gastric GISTs in this study appear to be relevant considering the critical roles played by PCs and MVBs recently demonstrated in tumourigenic processes.
authors.affiliation: Department of Pathology and Human Histology and Anatomy, Faculty of Medicine, University of Zaragoza, Zaragoza, Spain.
authors.forename: Tomás
authors.initials: T
authors.lastname: Castiella
authors.forename: Guillermo
authors.initials: G
authors.lastname: Muñoz
authors.forename: María José
authors.initials: MJ
authors.lastname: Luesma
authors.forename: Sonia
authors.initials: S
authors.lastname: Santander
authors.forename: Mario
authors.initials: M
authors.lastname: Soriano
authors.forename: Concepción
authors.initials: C
authors.lastname: Junquera
mesh_terms: D000199:Actins / Q000378:metabolism; D018952:Antigens, CD34 / Q000378:metabolism; D014408:Biomarkers, Tumor / Q000378:metabolism; D002923:Cilia / Q000473:pathology*; D003593:Cytoplasm / Q000378:metabolism; D003893:Desmin / Q000378:metabolism; D005770:Gastrointestinal Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology*; D046152:Gastrointestinal Stromal Tumors / Q000473:pathology / Q000648:ultrastructure*; D020869:Gene Expression Profiling; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007150:Immunohistochemistry; D016130:Immunophenotyping; D056885:Interstitial Cells of Cajal / Q000378:metabolism; D046529:Microscopy, Electron, Transmission; D010641:Phenotype; D019009:Proto-Oncogene Proteins c-kit / Q000378:metabolism; D009418:S100 Proteins / Q000378:metabolism; D014463:Ultrasonography
chemical_list: D000199:Actins; D018952:Antigens, CD34; D014408:Biomarkers, Tumor; D003893:Desmin; D009418:S100 Proteins; D019009:Proto-Oncogene Proteins c-kit
keywords: gastric gastrointestinal stromal tumours; primary cilia; ultrastructure