TY - JOUR
T1 - PDGFRA mutations in gastrointestinal stromal tumors
T2 - Frequency, spectrum and in vitro sensitivity to imatinib
AU - Corless, Christopher L.
AU - Schroeder, Arin
AU - Griffith, Diana
AU - Town, Ajia
AU - McGreevey, Laura
AU - Harrell, Patina
AU - Shiraga, Sharon
AU - Bainbridge, Troy
AU - Morich, Jason
AU - Heinrich, Michael C.
PY - 2005
Y1 - 2005
N2 - Purpose: Gastrointestinal stromal tumors (GISTs) commonly harbor oncogenic mutations of the KIT tyrosine kinase, which is a target for the kinase inhibitor imatinib. A subset of GISTs, however, contains mutations in the homologous kinase platelet derived growth factor receptor alpha (PDGFRA), and the most common of these mutations is resistant to imatinib in vitro. Little is known of the other types of PDGFRA mutations that occur in GISTs. Materials and Methods: We determined the KIT and PDGFRA mutation status of 1,105 unique GISTs using a combination of denaturing high-performance liquid chromatography and direct sequencing. Results: There were 80 tumors (7.2%) with a PDGFRA mutation: 66 in exon 18, 11 in exon 12, and three in exon 14. Transient expression of representative PDGFRA isoforms in CHO cells revealed imatinib sensitivity of exon 12 mutations (SPDHE566-571R and insertion ER561-562) and an exon 14 substitution (N659K). However, most isoforms with a substitution involving codon D842 in exon 18 (D842V, RD841-842KI, DI842-843IM) were resistant to the drug, with the exception of D842Y. Interestingly, other mutations in exon 18 (D846Y, N848K, Y849K and HDSN845-848P) were all imatinib sensitive. Proliferation studies with BA/F3 cell lines stably expressing selected PDGFRA mutant isoforms supported these findings. Conclusion: Including our cases, there are 289 reported PDGFRA-mutant GISTs, of which 181 (62.6%) had the imatinib-resistant substitution D842V. However, our findings suggest that more than one third of GISTs with PDGFRA mutations may respond to imatinib and that mutation screening may be helpful in the management of these tumors.
AB - Purpose: Gastrointestinal stromal tumors (GISTs) commonly harbor oncogenic mutations of the KIT tyrosine kinase, which is a target for the kinase inhibitor imatinib. A subset of GISTs, however, contains mutations in the homologous kinase platelet derived growth factor receptor alpha (PDGFRA), and the most common of these mutations is resistant to imatinib in vitro. Little is known of the other types of PDGFRA mutations that occur in GISTs. Materials and Methods: We determined the KIT and PDGFRA mutation status of 1,105 unique GISTs using a combination of denaturing high-performance liquid chromatography and direct sequencing. Results: There were 80 tumors (7.2%) with a PDGFRA mutation: 66 in exon 18, 11 in exon 12, and three in exon 14. Transient expression of representative PDGFRA isoforms in CHO cells revealed imatinib sensitivity of exon 12 mutations (SPDHE566-571R and insertion ER561-562) and an exon 14 substitution (N659K). However, most isoforms with a substitution involving codon D842 in exon 18 (D842V, RD841-842KI, DI842-843IM) were resistant to the drug, with the exception of D842Y. Interestingly, other mutations in exon 18 (D846Y, N848K, Y849K and HDSN845-848P) were all imatinib sensitive. Proliferation studies with BA/F3 cell lines stably expressing selected PDGFRA mutant isoforms supported these findings. Conclusion: Including our cases, there are 289 reported PDGFRA-mutant GISTs, of which 181 (62.6%) had the imatinib-resistant substitution D842V. However, our findings suggest that more than one third of GISTs with PDGFRA mutations may respond to imatinib and that mutation screening may be helpful in the management of these tumors.
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U2 - 10.1200/JCO.2005.14.068
DO - 10.1200/JCO.2005.14.068
M3 - Article
C2 - 15928335
AN - SCOPUS:23944476156
SN - 0732-183X
VL - 23
SP - 5357
EP - 5364
JO - Journal of Clinical Oncology
JF - Journal of Clinical Oncology
IS - 23
ER -