Objective To investiate the gastrointestinal stromal tumor (GIST) patients with tyrosine kinase receptor ( KIT) and platelet-derived growth factor receptor ( PDGFRA) gene mutation characteristics , as well as secondary imatinib re-sistance mechanisms .Methods 98 cases of patients with GIST tumor were examed with tissue for DNA extraction , polyme-rase chain reaction (PCR) amplification and direct sequencing to detect KIT exon 9,11,13,17 and PDGFRA gene mutation in exon 12 , 18;and secondary second test were performed in 65 imatinib-resistant patients .Results In the 98 patients , KIT mutations were found in 79 cases (80.6%), of which exon 11 mutations in 61 cases (62.2%), exon 9 mutations in 18 cases (18.4%);PDGFRA mutations in 3 cases (3.1%).Gender, age, and among patients with advanced GIST GIST patients and potentially malignant mutation was with no significant difference ( P >0.05);while different parts of GIST KIT exon 11 mutation incidence was significantly ( P <0.05).In 65 cases of secondary resistant cases , four patients developed a seconda-ry mutation, gene expression of KIT exon 17 codon 2467 point T is replaced by G (T2467G), resulting in 823 amino acids encoded by the codons casein converted to aspartic acid .Conclusion It demonstrated that the KIT mutations are common in GIST patients , between different parts of the KIT exon 11 mutation rate difference was statistically significant .Secondary ima-tinib resistance may be associated with KIT exon 17 of the gene codon 2467 point T is replaced by G (T2467G) related.%目的：探讨胃肠道间质瘤（ GIST）患者酪氨酸激酶受体（ KIT）和血小板源性生长受体（ PDGFRA）基因突变的特点，以及伊马替尼的继发耐药机制。方法对98例GIST患者肿瘤组织进行DNA抽提、聚合酶链反应（ PCR）扩增和直接测序，检测KIT基因外显子9、11、13、17和PDGFRA基因12、18外显子突变；并对伊马替尼继发耐药的65例患者进行2次检测。结果98例患者中，KIT突变79例（80妸．6％），其中外显子11突变61例（62．2％），外显子9突变18例（18．4％）；PDGFRA突变3例（3．1％）。不同性别、年龄以及晚期GIST患者和潜在恶性的GIST患者间突变比较差异无统计学意义（ P ＞0．05）；而不同部位GIST的KIT外显子11突变发生率差异有统计学意义（ P ＜0．05）。65例继发耐药病例中，4例患者发生二次突变，表现为KIT基因第17外显子密码子第2467位点的T为G所替换（ T2467 G），导致823密码子编码氨基酸由酪氨酸转变为天冬氨酸。结论 KIT基因突变在GIST患者中常见，不同部位间KIT外显子11突变发生率差异有统计学意义。伊马替尼继发耐药可能与KIT基因第17外显子密码子第2467位点T为G所替换（T2467G）相关。
展开▼
