Zarubina K I, Parovichnikova E N, Surin V L, Pshenichnikova O S, Gavrilina O A, Isinova G A, Troitskaia V V, Sokolov A N, Gal'tseva I V, Kapranov N M, Davydova I O, Obukhova T N, Sudarikov A B, Savchenko V G
National Research Center for Hematology.
Ter Arkh. 2020 Sep 1;92(7):31-42. doi: 10.26442/00403660.2020.07.000772.
The study of activating mutations (NRAS,KRAS,FLT3,JAK2,CRLF2genes) of RAS/RAF/MEK/ERK and JAK/STAT signaling pathways in B-cell acute lymphoblastic leukemia (B-ALL) in adult patients which are included in Russian multicenter clinical trials.
Within the multicenter study there were 119 adult patients included withde novoB-ALL. The study was considered as prospective and retrospective. The group withBCR-ABL1-negative B-ALL consisted of up to 93 patients (45 male and 48 female, at the age of 17 to 59, the median age 31), they were treated according to the protocols ALL-2009, ALL-2016. The median follow-up lasted for 19 months (1119). The group withBCR-ABL1-positive B-ALL with up to 26 patients (10 male and 16 female, at the age of 23 to 78, the median age 34 years) was included in the study as well. The treatment was carried out according to the protocols ALL-2009 and ALL-2012 in combination with tyrosine kinase inhibitors. The median follow-up lasted for 23 months (4120). The molecular analysis of activating mutations inNRAS,KRASgenes (RAS/RAF/MEK/ERK signaling pathway) andJAK2,CRLF2genes (JAK/STAT signaling cascade) was performed via Sanger sequencing. The internal tandem duplications (ITDs) inFLT3gene were studied by fragment analysis. The evaluation of CRLF2 expression was fulfilled via flow cytometry.
Activating mutations inNRAS,KRAS,FLT3genes were found in 22 (23.6%) patients withBCR-ABL1-negative B-ALL. In total, 23 mutations were revealed in theNRAS(n=9),KRAS(n=12), andFLT3(n=2) genes, according to statistics that was significantly more frequent than withBCR-ABL1-positive B-ALL, these genes mutations were not identified in patients (p=0.007). The frequency of mutations detection inKRASandNRASgenes in patients withBCR-ABL1-negative B-ALL was comparable as 12.9% (12 of 93) to 9.7% (9 of 93), respectively (p=0.488). One patient was simultaneously revealed 2 mutations in theKRASgene (in codons 13 and 61).FLT3-ITD mutations were detected in 3.5% (2 of 57) cases ofBCR-ABL1-negative B-ALL. In patients withBCR-ABL1-positive B-ALLFLT3-ITD mutations were not assessed. Violations in the JAK/STAT signaling cascade were detected in 4 (4.3%) patients withBCR-ABL1-negative B-ALL. They were represented by the missense mutations ofJAK2gene (n=3) and the overexpression of CRLF2 (n=2); in one patient were detected the overexpression of CRLF2 and a mutation inJAK2gene simultaneously. No mutations were found inCRLF2gene. In patients withBCR-ABL1-positive B-ALL noJAK2mutations were detected. As long as analyzing demographic and clinical laboratory parameters between groups of patients with and without mutations, there were no statistically significant differences obtained. In the analyzed groups of patients, long-term therapy results did not differentiate according to the mutations presence inNRAS,KRAS,FLT3,JAK2genes. Also, substantive differences were not shown in the rate of the negative status achievement of the minimum residual disease between patients with and without activating mutations in the control points of the protocol (on the 70th, 133rd and 190th days).
NRAS,KRAS,FLT3,JAK2activating mutations do not affect the long-term results of the therapy and the rate of the negative status achievement of the minimum residual disease in patients withBCR-ABL1-negative B-ALL treated by the Russian multicenter clinical trials.
对纳入俄罗斯多中心临床试验的成年B细胞急性淋巴细胞白血病（B-ALL）患者的RAS/RAF/MEK/ERK和JAK/STAT信号通路激活突变（NRAS、KRAS、FLT3、JAK2、CRLF2基因）进行研究。
在多中心研究中，纳入了119例初发B-ALL成年患者。该研究兼具前瞻性和回顾性。BCR-ABL1阴性B-ALL组最多包含93例患者（45例男性和48例女性，年龄17至59岁，中位年龄31岁），他们按照ALL-2009、ALL-2016方案接受治疗。中位随访时间为19个月（1至19个月）。BCR-ABL1阳性B-ALL组最多有26例患者（10例男性和16例女性，年龄23至78岁，中位年龄34岁）也纳入了该研究。治疗按照ALL-2009和ALL-2012方案联合酪氨酸激酶抑制剂进行。中位随访时间为23个月（4至20个月）。通过桑格测序对NRAS、KRAS基因（RAS/RAF/MEK/ERK信号通路）以及JAK2、CRLF2基因（JAK/STAT信号级联）的激活突变进行分子分析。通过片段分析研究FLT3基因中的内部串联重复（ITD）。通过流式细胞术评估CRLF2表达。
在22例（23.6%）BCR-ABL1阴性B-ALL患者中发现NRAS、KRAS、FLT3基因激活突变。NRAS（n = 9）、KRAS（n = 12）和FLT3（n = 2）基因共发现23个突变，据统计，这明显比BCR-ABL1阳性B-ALL更频繁，这些基因突变在患者中未被发现（p = 0.007）。BCR-ABL1阴性B-ALL患者中KRAS和NRAS基因突变检测频率相当，分别为12.9%（93例中的12例）和9.7%（93例中的9例）（p = 0.488）。1例患者同时在KRAS基因（密码子13和61）中发现2个突变。在57例BCR-ABL1阴性B-ALL病例中，3.5%（2例）检测到FLT3-ITD突变。在BCR-ABL1阳性B-ALL患者中未评估FLT3-ITD突变。在4例（4.3%）BCR-ABL1阴性B-ALL患者中检测到JAK/STAT信号级联异常。它们表现为JAK2基因错义突变（n = 3）和CRLF2过表达（n = 2）；1例患者同时检测到CRLF2过表达和JAK2基因突变。CRLF2基因未发现突变。在BCR-ABL1阳性B-ALL患者中未检测到JAK2突变。在分析有突变和无突变患者组之间的人口统计学和临床实验室参数时，未获得统计学上的显著差异。在所分析的患者组中，长期治疗结果并未根据NRAS、KRAS、FLT3、JAK2基因中的突变情况而有所不同。在方案的控制点（第70天、133天和190天），有激活突变和无激活突变患者之间在最小残留病阴性状态达成率方面也未显示出实质性差异。
NRAS、KRAS、FLT3、JAK2激活突变不影响俄罗斯多中心临床试验治疗的BCR-ABL1阴性B-ALL患者的长期治疗结果以及最小残留病阴性状态达成率。
