biostudies-literatureUnknown9(7)Ihle MAAberrantly expressed microRNAs (miRNAs) are involved in many diseases including cancer. In gastrointestinal stromal tumours (GISTs) expression of miR-221 and miR-222 is reduced compared to control tissue and other sarcomas but the functional effects of this downregulation are not fully understood. This study aimed at evaluating the miR-221 and miR-222 expression profiles in different GIST subtypes and the functional role of these miRNAs. Expression of miR-221 and miR-222 was analysed in six KIT exon 9 and three KIT exon 11 mutated and nine wildtype GISTs by qPCR. Viability and apoptosis were examined in three different, KIT positive GIST cell lines (GIST882, GIST-T1 and GIST48) after overexpression of these miRNAs. The modulation of KIT and the PI3K/AKT pathways was determined by Western bMolecular oncology1421-33https://www.ebi.ac.uk/biostudies/studies/S-EPMC5528808biostudies-literaturemiRNA-221 and miRNA-222 induce apoptosis via the KIT/AKT signalling pathway in gastrointestinal stromal tumours.PMC5528808Ihle MAHuss SSchildhaus HUBuettner RWardelmann EFassunke JTrautmann MBauer SMerkelbach-Bruse SKuenstlinger HHeydt CfalsemiRNA-221 and miRNA-222 induce apoptosis via the KIT/AKT signalling pathway in gastrointestinal stromal tumours.Aberrantly expressed microRNAs (miRNAs) are involved in many diseases including cancer. In gastrointestinal stromal tumours (GISTs) expression of miR-221 and miR-222 is reduced compared to control tissue and other sarcomas but the functional effects of this downregulation are not fully understood. This study aimed at evaluating the miR-221 and miR-222 expression profiles in different GIST subtypes and the functional role of these miRNAs. Expression of miR-221 and miR-222 was analysed in six KIT exon 9 and three KIT exon 11 mutated and nine wildtype GISTs by qPCR. Viability and apoptosis were examined in three different, KIT positive GIST cell lines (GIST882, GIST-T1 and GIST48) after overexpression of these miRNAs. The modulation of KIT and the PI3K/AKT pathways was determined by Western b2015-01-01T00:00:00Z2015 Aug2025-04-26T08:54:50.546Z2019-03-27T02:51:44ZS-EPMC55288082589877310.1016/j.molonc.2015.03.013