Cytogenetics Department, Bone Marrow Transplantation Unit, Instituto Nacional de Câncer José de Alencar Gomes da Silva (INCA).
Post-Graduation Program in Oncology, National Cancer Institute (INCA).
J Pediatr Hematol Oncol. 2022 Apr 1;44(3):e719-e722. doi: 10.1097/MPH.0000000000002386.
About 25% of the patients with the translocation t(11;19)(q23;p13.3)/KMT2A-MLLT1 present three-way or more complex fusions, associated with a worse prognosis, suggesting that a particular mechanism creates functional KMT2A fusions for this condition. In this work, we show a cryptic three-way translocation t(9;11;19). Interestingly, long-distance inverse polymerase chain reaction sequencing revealed a KMT2A-MLLT1 and the yet unreported out-of-frame SEC16A-KMT2A fusion, associated with low SEC16A expression and KMT2A overexpression, in an infant with B-acute lymphoblastic leukemia presenting a poor prognosis. Our case illustrates the importance of molecular cytogenetic tests in selecting cases for further investigations, which could open perspectives regarding novel therapeutic approaches for poor prognosis childhood leukemias.
约 25% 的 t(11;19)(q23;p13.3)/KMT2A-MLLT1 易位患者存在三向或更多复杂融合，预后较差，提示存在特定机制为该疾病产生功能性 KMT2A 融合。在本研究中，我们发现了一种隐匿性三向易位 t(9;11;19)。有趣的是，长距离反转聚合酶链反应测序显示，在预后不良的婴儿 B 急性淋巴细胞白血病中存在 KMT2A-MLLT1 和尚未报道的框架外 SEC16A-KMT2A 融合，与 SEC16A 表达降低和 KMT2A 过表达相关。我们的病例说明了分子细胞遗传学检测在选择进一步研究病例中的重要性，这可能为预后不良的儿童白血病的新型治疗方法开辟前景。
