Tidow N, Pilz C, Teichmann B, Müller-Brechlin A, Germeshausen M, Kasper B, Rauprich P, Sykora K W, Welte K
Department of Pediatric Hematology and Oncology, Hannover Medical School, Germany.
Blood. 1997 Apr 1;89(7):2369-75.
Recently, point mutations in the gene of the granulocyte colony-stimulating factor (G-CSF) receptor have been reported in two patients with severe congenital neutropenia who developed acute myeloid leukemia (AML). We investigated the frequency of these specific G-CSF receptor mutations in patients with congenital neutropenia undergoing treatment with r-metHuG-CSF (Filgrastim) and the clinical relevance of these mutations. Nucleotides 2306 to 2561 including the critical region (nucleotides 2384-2429) from the intracellular domain of the G-CSF receptor gene were amplified by reverse transcriptase-polymerase chain reaction. Detection of point mutations was performed with specific restriction enzyme analysis, as well as sequencing of PCR products. Both genomic DNA and cDNA from neutrophils and mononuclear cells were analyzed from 28 patients with severe congenital neutropenia. Four of 28 patients with congenital neutropenia displayed a point mutation in the tested cytoplasmic region of the G-CSF receptor gene. The point mutations replace a glutamine codon by a stop codon of the G-CSF receptor gene. Among these four congenital neutropenia patients with a mutated G-CSF receptor, two developed AML. All four patients were investigated regularly and no correlation between occurrence of G-CSF receptor mutation and time or dose of r-metHuG-CSF treatment was found. No point mutations in the G-CSF receptor critical domain could be detected in cells from the other 24 congenital neutropenia patients. Furthermore, we tested six family members of the two patients with AML including mothers and fathers, one sister, and one brother who suffers from congenital neutropenia, as well. All family members displayed a normal G-CSF receptor gene. After the acquisition of the G-CSF receptor mutations, the congenital neutropenia patients continued to respond to G-CSF therapy with an increase in absolute neutrophils in the peripheral blood. We conclude that the point mutations in the critical region of the intracellular part of the G-CSF receptor occur spontaneously and are not inherited. From our data, we suggest that the described G-CSF receptor point mutations do not alter the response to treatment with r-metHuG-CSF and are not the cause of severe congenital neutropenia.
最近，在两名患严重先天性中性粒细胞减少症并发展为急性髓系白血病（AML）的患者中，已报道粒细胞集落刺激因子（G-CSF）受体基因存在点突变。我们调查了接受r-甲硫氨酸人G-CSF（非格司亭）治疗的先天性中性粒细胞减少症患者中这些特定G-CSF受体突变的频率以及这些突变的临床相关性。通过逆转录聚合酶链反应扩增G-CSF受体基因胞内结构域中包括关键区域（核苷酸2384 - 2429）的核苷酸2306至2561。使用特异性限制性酶切分析以及PCR产物测序进行点突变检测。对28例严重先天性中性粒细胞减少症患者的中性粒细胞和单核细胞的基因组DNA和cDNA进行了分析。28例先天性中性粒细胞减少症患者中有4例在G-CSF受体基因的检测胞质区域显示点突变。这些点突变使G-CSF受体基因的谷氨酰胺密码子被终止密码子取代。在这4例G-CSF受体突变的先天性中性粒细胞减少症患者中，2例发展为AML。对所有4例患者进行了定期调查，未发现G-CSF受体突变的发生与r-甲硫氨酸人G-CSF治疗的时间或剂量之间存在相关性。在其他24例先天性中性粒细胞减少症患者的细胞中未检测到G-CSF受体关键结构域的点突变。此外，我们检测了两名AML患者的六名家庭成员，包括母亲、父亲、一个患先天性中性粒细胞减少症的姐姐和一个弟弟。所有家庭成员的G-CSF受体基因均正常。获得G-CSF受体突变后，先天性中性粒细胞减少症患者继续对G-CSF治疗有反应，外周血中绝对中性粒细胞数增加。我们得出结论，G-CSF受体胞内部分关键区域的点突变是自发发生的，而非遗传所得。根据我们的数据，我们认为所描述的G-CSF受体点突变不会改变对r-甲硫氨酸人G-CSF治疗的反应，也不是严重先天性中性粒细胞减少症的病因。
