95% Ph ＋ CML患者BCR基因在M-bcr发生断裂，与ABL基因断点外显子2融合形成e13a2或者e14a2转录本，编码p210融合蛋白。

重点来了：e14a2和e13a2融合位点仅有75个碱基的差异，但临床意义却不一样。 BCR-ABL p210 e13a2亚型的患者预后较差。 2019年，在Leukemia杂志发表了一篇综述文章，汇总了近年来对BCR-ABL各亚型CML患者的研究报道【1】。 与e14a2亚型 CML患者相比，e13a2亚型患者预后较差，复发率较高。 此外，在CML患者的停药相关研究方面，有报道显示，在对249名已获得深分子反应且已停止治疗的患者的初步分析中，仅62名（25%）患者伴随e13a2转录本，低于随机分 …

A significant difference was found between e13a2 and e14a2 when comparing white blood cells (88 vs. 65 × 10(9)/L, respectively; P<0.001) and platelets (296 vs. 430 × 10(9)/L, respectively; P<0.001) at diagnosis, indicating a distinct disease phenotype.

A possible differential impact of the corresponding BCR-ABL1 transcript variants e13a2 (“b2a2”) and e14a2 (“b3a2”) on disease phenotype and outcome is still a subject of debate. A total of 1105 newly diagnosed imatinib-treated patients were analyzed according to transcript type at diagnosis (e13a2, n=451; e14a2, n=496; e13a2+e14a2, n=158).

The e13a2 BCR-ABL transcript negatively affects sustained deep molecular response and the achievement of treatment-free remission in patients with chronic myeloid leukemia who receive tyrosine kinase inhibitors

Chronic myeloid leukemia (CML) is characterized by the presence of the BCR-ABL1 fusion gene. In more than 95% of CML patients, the typical BCR-ABL1 transcript subtypes are e13a2 (b2a2), e14a2 (b3a2), or the simultaneous expression of both.

存在两种典型的 mRNA 变体，它们在 75 碱基对 BCR 外显子 14 的存在与否方面有所不同：e13a2（缺少外显子 14，也称为“b2a2”）和 e14a2 BCR-ABL 转录物（“b3a2”）。e14a2 BCR-ABL 癌蛋白的额外 25 个氨基酸残基的重要性在伊马替尼之前的时代得到了广泛研究。

2019年10月8日 · In 20–30% of cases, the breakpoint on chromosome 22 is downstream to BCR exon 1, resulting from the fusion of ABL1 exon 2 on chromosome 9 with either BCR exon 13 or BCR exon 14 on chromosome 22....

2019年5月15日 · Conclusions: The e13a2 transcript hinders the achievement of deep responses and the possibility of stopping TKI treatment in patients with CML. Keywords: breakpoint cluster region-Abelson murine leukemia viral oncogene homolog 1 (BCR-ABL) transcript; chronic myelogenous leukemia; deep molecular response; treatment-free remission; tyrosine ...

2018年11月29日 · The most significant finding was that patients attempting TFR with e14a2 BCR-ABL1 transcripts were more likely to remain in TFR at 12 months (65%; n=24/37) in comparison to the e13a2 transcript (34%; n=10/29), p = 0.008.