scholarly journals KIT and BRAF heterogeneous mutations in gastrointestinal stromal tumors after secondary imatinib resistance

2014 ◽  
Vol 18 (4) ◽  
pp. 796-802 ◽  
Author(s):  
Song Zheng ◽  
Ke-er Huang ◽  
Yue-long Pan ◽  
Yao Zhou ◽  
Song-dan Pan ◽  
...  
2006 ◽  
Vol 24 (29) ◽  
pp. 4764-4774 ◽  
Author(s):  
Michael C. Heinrich ◽  
Christopher L. Corless ◽  
Charles D. Blanke ◽  
George D. Demetri ◽  
Heikki Joensuu ◽  
...  

Purpose Gastrointestinal stromal tumors (GISTs) commonly harbor oncogenic mutations of the KIT or platelet-derived growth factor alpha (PDGFRA) kinases, which are targets for imatinib. In clinical studies, 75% to 90% of patients with advanced GISTs experience clinical benefit from imatinib. However, imatinib resistance is an increasing clinical problem. Patients and Methods One hundred forty-seven patients with advanced, unresectable GISTs were enrolled onto a randomized, phase II clinical study of imatinib. Specimens from pretreatment and/or imatinib-resistant tumors were analyzed to identify molecular correlates of imatinib resistance. Secondary kinase mutations of KIT or PDGFRA that were identified in imatinib-resistant GISTs were biochemically profiled for imatinib sensitivity. Results Molecular studies were performed using specimens from 10 patients with primary and 33 patients with secondary resistance. Imatinib-resistant tumors had levels of activated KIT that were similar to or greater than those typically found in untreated GISTs. Secondary kinase mutations were rare in GISTs with primary resistance but frequently found in GISTs with secondary resistance (10% v 67%; P = .002). Evidence for clonal evolution and/or polyclonal secondary kinase mutations was seen in three (18.8%) of 16 patients. Secondary kinase mutations were nonrandomly distributed and were associated with decreased imatinib sensitivity compared with typical KIT exon 11 mutations. Using RNAi technology, we demonstrated that imatinib-resistant GIST cells remain dependent on KIT kinase activity for activation of critical downstream signaling pathways. Conclusion Different molecular mechanisms are responsible for primary and secondary imatinib resistance in GISTs. These findings have implications for future approaches to the growing problem of imatinib resistance in patients with advanced GISTs.


2013 ◽  
Vol 2 (6) ◽  
pp. e24452 ◽  
Author(s):  
Badreddin Edris ◽  
Stephen Willingham ◽  
Kipp Weiskopf ◽  
Anne K Volkmer ◽  
Jens-Peter Volkmer ◽  
...  

2020 ◽  
Vol 21 (18) ◽  
pp. 6975
Author(s):  
Azadeh Amirnasr ◽  
Stefan Sleijfer ◽  
Erik A. C. Wiemer

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal malignancies found in the gastrointestinal tract. At a molecular level, most GISTs are characterized by gain-of-function mutations in V-Kit Hardy–Zuckerman 4 Feline Sarcoma Viral Oncogene Homolog (KIT) and Platelet Derived Growth Factor Receptor Alpha (PDGFRA), leading to constitutive activated signaling through these receptor tyrosine kinases, which drive GIST pathogenesis. In addition to surgery, treatment with the tyrosine kinase inhibitor imatinib forms the mainstay of GIST treatment, particularly in the advanced setting. Nevertheless, the majority of GISTs develop imatinib resistance. Biomarkers that indicate metastasis, drug resistance and disease progression early on could be of great clinical value. Likewise, novel treatment strategies that overcome resistance mechanisms are equally needed. Non-coding RNAs, particularly microRNAs, can be employed as diagnostic, prognostic or predictive biomarkers and have therapeutic potential. Here we review which non-coding RNAs are deregulated in GISTs, whether they can be linked to specific clinicopathological features and discuss how they can be used to improve the clinical management of GISTs.


2007 ◽  
Vol 13 (8) ◽  
pp. 2369-2377 ◽  
Author(s):  
Francesca="C"> Miselli ◽  
Paola Casieri ◽  
Tiziana Negri ◽  
Marta Orsenigo ◽  
M. Stefania Lagonigro ◽  
...  

2012 ◽  
Vol 5 (2) ◽  
pp. 552-558 ◽  
Author(s):  
XIAO-WEI HOU ◽  
CHEN-GUANG BAI ◽  
XIAO-HONG LIU ◽  
CEN QIU ◽  
LING HUANG ◽  
...  

Oncotarget ◽  
2015 ◽  
Vol 7 (2) ◽  
pp. 1367-1379 ◽  
Author(s):  
Senyan Lai ◽  
Guihua Wang ◽  
Xiaonian Cao ◽  
Xuelai Luo ◽  
Guoping Wang ◽  
...  

2018 ◽  
Vol 371 (1) ◽  
pp. 287-296 ◽  
Author(s):  
Wen-Kuan Huang ◽  
Pinar Akçakaya ◽  
Anastasia Gangaev ◽  
Linkiat Lee ◽  
Katarina Zeljic ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document