Moura, David S.Ramos, RafelFernandez-Serra, AntonioSerrano Piñol, M. TeresaCruz, JuliaAlvarez-Alegret, RamiroOrtiz-Duran, RosaVicioso, LuisGomez-Dorronsoro, Maria LuisaGarcía del Muro Solans, XavierMartinez-Trufero, JavierRubió Casadevall, JordiSevilla, IsabelLainez, NuriaGutiérrez García, Antonio ManuelSerrano, CésarLopez-Alvarez, MariaHindi, NadiaTaron, MiquelLópez Guerrero, José AntonioMartin-Broto, Javier2021-06-212021-06-212018-04-031949-2553https://hdl.handle.net/2445/178609Introduction: there are limited findings available on KIT-negative GIST-like (KNGL) population. Also, KIT expression may be post-transcriptionally regulated by miRNA221 and miRNA222. Hence, the aim of this study is to characterize KNGL population, by differential gene expression, and to analyze miRNA221/222 expression and their prognostic value in KNGL patients. Methods: KIT, PDGFRA, DOG1, IGF1R, MIR221 and MIR222 expression levels were determined by qRT-PCR. We also analyzed KIT and PDGFRA mutations, DOG1 expression, by immunohistochemistry, along with clinical and pathological data. Disease-free survival (DFS) and overall survival (OS) differences were calculated using Log-rank test. Results: hierarchical cluster analyses from gene expression data identified two groups: group I had KIT, DOG1 and PDGFRA overexpression and IGF1R underexpression and group II had overexpression of IGF1R and low expression of KIT, DOG1 and PDGFRA. Group II had a significant worse OS (p = 0.013) in all the series, and showed a tendency for worse OS (p = 0.11), when analyzed only the localized cases. MiRNA222 expression was significantly lower in a control subset of KIT-positive GIST (p < 0.001). OS was significantly worse in KNGL cases with higher expression of MIR221 (p = 0.028) or MIR222 (p = 0.014). Conclusions: we identified two distinct KNGL subsets, with a different prognostic value. Increased levels of miRNA221/222, which are associated with worse OS, could explain the absence of KIT protein expression of most KNGL tumors.13 p.application/pdfengcc-by (c) Moura, David S. et al., 2018https://creativecommons.org/licenses/by/4.0/RNAExpressió gènicaPacientsRNAGene expressionPatientsinfo:eu-repo/semantics/article6881872021-06-21info:eu-repo/semantics/openAccess29707131