慢性髓性白血病一种新剪接体ABL△exon7+35INS的发现及其与酪氨酸激酶抑制剂耐药的相关性

摘要

目的 探讨ABL基因的剪接体ABL△exon7和ABL35INS是否与酪氨酸激酶抑制剂(TKI)耐药的发生有关.方法 采用聚丙烯酰胺凝胶电泳法结合PCR扩增产物直接测序法,检测74名健康人和76例慢性髓性白血病(CML)患者(TKI治疗有效组53例,耐药组23例)ABL△exon7和ABL35INS剪接体的发生率.结果 发现并鉴定一种新的剪接体ABL△exon7+35INS(ABL△exon7和ABL35INS剪接体同时存在),在健康对照组、TKI治疗有效组和耐药组检出率分别为10.8％(8/74)、7.5％(4/53)和8.7％(2/23).74名健康对照者中47名(63.5％)表达ABL△exon7剪接体,8名(10.8％)表达ABL35INS剪接体;53例TKI治疗有效的CML患者中30例(56.6％)表达ABL△exon7剪接体,5例(9.4％)表达ABL351NS剪接体;23例发生耐药的CML患者中12例(52.2％)表达ABL△exon7剪接体,3例(13.0％)表达ABL35INS剪接体,比较以上各组结果,差异均无统计学意义(P值均＞ 0.05).结论 新剪接体ABL△exon7+35INS、ABL△exon7和ABL35INS与TKI治疗发生耐药无关,同时发现ABL35INS剪接体的发生往往会伴随外显子7的缺失.%Objective To explore whether the ABL△exon7 and ABL35INS spliceosome contributed to TKIs resistance.Methods Screening ABL△exon7 and ABL35INS in 74 normal people and 76 CML patients (53 patients in remission and 23 patients with TKIs resistance) by using polyacrylamide gel electrophoresis combined with cloning sequencing.Results A novel spliceosome ABL△exon7+35INS (ABL△exon7 and ABL35INS existed at the same time) was identified and the mutation was detected in 8 (10.8％) of 74 normal people,4 (7.5％) of 53 remission patients and 2 (8.7％) of 23 resistant patients.While 47 (63.5％) cases expressed ABL△exon7 and 8 (10.8％) cases expressed ABL35INS in 74 healthy people,30 (56.6％) cases expressed ABL△exon7 and 5 (9.4％) cases expressed ABL35INS in 53 remission patients,12 (52.2％) cases expressed ABL△exon7 and 3 (13.0％) cases expressed ABL35INs in 23 resistant patients.Three kinds of spliceosome in all groups had no statistical difference.Conclusion ABL△exon7 + 351NS,ABL△exon7 and ABL35INS may be not uncommon in ABL gene and were unrelated to resistance in CML with TKIs treatment.ABL351NS were often accompanying with exon 7 deletion.