实时定量逆转录-聚合酶链反应监测慢性粒细胞白血病患者融合基因转录本水平及其变化

Detection and quantification of BCR-ABL transcripts in patients with chronic myeloid leukemia by real-time quantitative reverse transcriptase polymerase chain reaction

目的探讨实时定量逆转录聚合酶链反应(RT PCR)在监测慢性粒细胞白血病(慢粒)患者微小残留病变、考核疗效以及预测疾病预后方面的应用。方法应用实时定量RT PCR对11例慢粒患者治疗前后融合基因(BCR ABL)转录本水平的变化进行监测,对55例不同病期患者之间的转录本水平进行比较。结果对于慢性期患者,造血干细胞移植后其BCR ABL转录本水平明显下降,甚至检测不到,甲磺酸伊马替尼(格列卫)治疗可获得类似结果,而羟基脲、干扰素α或三尖杉酯碱治疗后,其BCR ABL转录本水平虽有下降但仍维持在较高水平;患者发生急变时,其BCR ABL转录本水平升高约10倍;急变期患者的转录本水平明显高于慢性期或加速期患者。结论实时定量RT PCR方法准确可靠,对于监测慢粒患者的微小残留病变、考核疗效以及预测慢粒急变具有重要的临床应用价值。

Objective To investigate the effect of real-time quantitative reverse transcriptase polymerase chain reaction (RT-PCR) approach in chronic myeloid leukemia (CML) for detecting the minimal residual disease (MRD) or monitoring the treatment response and predicting the prognosis. Methods Fifty-six CML patients, 39 males and 17 females, aged 39 (16~66), with disease history and frozen RNA specimens were studied, 31 of which were in the incipient chronic phase, 7 in the accelerated phase, and 17 in the rapidly progressing phase. Three or more frozen RNA specimens collected before and after treatment were preserved in 11 of the patients. Breakpoint cluster region-Abelson murine leukemia viral oncogene (BCR-ABL) of the patients in different CML stages was analyzed by RT-PCR approach. Results^The BCR-ABL transcript of those patients remaining in chronic period after treatment decreased to 1/3 that of the baseline level six months after the initiation of treatment and then remained at that level. The BCR-ABL transcript of those in which progressing change occurred increased when such change occurred. After allogeneic transplantation of peripheral blood stem cells the BCR-ABL level decreased significantly. The median DoseN in the 17 progressing patients was 10 492, significantly higher than those of the 31 patients in chronic phase (5920) and in the 7 patients in accelerated phase (4444, both P<0.05). The minimal residual disease and the treatment response were closely associated with the level and its variation of BCR-ABL transcripts, the transcripts level in blastic crisis was significantly higher than that in chronic phase or accelerated phase. Conclusion Real-time quantitative RT-PCR is reliable and can be used to detect the minimal residual disease, monitor the treatment outcome, and predicting blastic crisis.