儿童急性淋巴细胞白血病中RAS基因突变的检测及其临床意义

Detection of RAS gene mutation and its clinical significance in children with acute lymphoblastic leukemia

摘要:

目的 探讨RAS基因在儿童急性淋巴细胞白血病中的突变率及其临床意义。 方法 回顾性收集2015年1月至2020年1月于郑州大学第三附属医院收治的新确诊且完成二代测序的急性淋巴细胞白血病120例患儿病例资料，分析其临床及分子学特征，以及RAS基因突变对急性淋巴细胞白血病患儿总生存率的影响。 结果 120例患儿中，共有35例（29.2%）患儿伴有RAS基因突变，其中仅KRAS基因突变30例（25.0%），NRAS基因突变伴KRAS基因突变5例（4.2%）。全部NRAS基因突变及71%（25/35）KRAS基因突变位于第12、13号密码子。RAS基因突变在急性B淋巴细胞白血病中检出率为33.3%（35/105），未在急性T淋巴细胞白血病中检出。失访11例（9.2%），随访109例患儿中死亡16例（14.7%）。RAS基因突变患儿的2年总生存率低于RAS基因阴性患儿（P<0.05）。伴RAS基因突变急性淋巴细胞白血病患儿合并WT1基因过表达、初诊白细胞数计数>50×10⁹/L时，预后更差（P<0.05）。 结论 RAS基因突变多发生于急性B淋巴细胞白血病，对预后有不良影响。

Abstract:

Objective To investigate the mutation rate of the RAS gene and its clinical significance in children with acute lymphoblastic leukemia. Methods A retrospective analysis was performed on the medical data of 120 children with newly diagnosed acute lymphoblastic leukemia, who were admitted to the Third Affiliated Hospital of Zhengzhou University from January 2015 to January 2020 and underwent next-generation sequencing. The clinical and molecular features were analyzed. The impact of RAS gene mutation on the overall survival rate was evaluated in these children. Results Among the 120 children, 35 (29.2%) had RAS gene mutation, 30 (25.0%) had KRAS gene mutation, and 5 (4.2%) had both NRAS and KRAS gene mutations. All NRAS mutations and 71% (25/35) of KRAS mutations were located at the 12th and 13th codons. RAS gene mutation was detected in 35 (33.3%) out of 105 children with B-lineage acute lymphoblastic leukemia, but it was not detected in those with acute T lymphocyte leukemia. Of all the children, 11 (9.2%) were lost to follow-up, and among the 109 children followed up, 16 (14.7%) died. The children with RAS gene mutation had a significantly lower 2-year overall survival rate than those without RAS gene mutation (P<0.05). The prognosis of children with RAS gene mutation combined with WT1 overexpression and WBC>50×109/L at diagnosis was worse (P<0.05). Conclusions RAS gene mutation is commonly observed in children with B-lineage acute lymphoblastic leukemia and may have an adverse effect on prognosis.