tailieunhanh - báo cáo hóa học:" The role of mutational analysis of KIT and PDGFRA in gastrointestinal stromal tumors in a clinical setting"

Tuyển tập các báo cáo nghiên cứu về hóa học được đăng trên tạp chí sinh học đề tài : The role of mutational analysis of KIT and PDGFRA in gastrointestinal stromal tumors in a clinical setting | Maleddu et al. Journal of Translational Medicine 2011 9 75 http content 9 1 75 JOURNAL OF TRANSLATIONAL MEDICINE REVIEW Open Access The role of mutational analysis of KIT and PDGFRA in gastrointestinal stromal tumors in a clinical setting Alessandra Maleddu 1 Maria A Pantaleo1 2 Margherita Nannini1 and Guido Biasco1 2 Abstract Gastrointestinal stromal tumors GIST are the most common mesenchymal tumors of the gastrointestinal tract. Most GIST harbor a mutation affecting either the KIT or PDGFRA genes whereas a small subgroup of tumors is wild type for mutations. Mutation of tyrosine kinase receptors is a mechanism of drug resistance that can occur either at the beginning of treatment primary resistance or during the course of therapy secondary resistance . In addition mutational status can predict the response to treatment with tyrosine kinase inhibitors but the role of mutational status as a prognostic factor remains controversial. Evidence of a potential role of mutational status as a prognostic factor has emerged over the past decade. The presence of KIT exon 11 insertion deletion involving either one or both Trp557-Lys558 amino acids correlates with a poorer clinical outcome if compared to patients with tumors wild type for KIT exon 11 mutations. A malignant clinical behavior has also been documented for KIT exon 13 and KIT exon 9 mutant GIST. Patients with GIST harboring a PDGFRA mutation seem to have a better prognosis than the others. The aim of this paper is to review the clinical significance of tyrosine kinase mutational status. Introduction Gastrointestinal stromal tumors GIST are rare tumors of the gastrointestinal tract. They arise mostly in the stomach followed by the small bowel and colon. Less frequently they are found in the rectum esophagus or in an extra-gastrointestinal location. The biology of GIST has been widely investigated since Hirota et al. 1 demonstrated mutations of the KIT receptor as a pathogenic .