OncoTargets and Therapy (Nov 2016)

E2A-PBX1 exhibited a promising prognosis in pediatric acute lymphoblastic leukemia treated with the CCLG-ALL2008 protocol

  • Hu YX,
  • He HL,
  • Lu J,
  • Wang Y,
  • Xiao PF,
  • Li JQ,
  • Li J,
  • Sun YN,
  • Lv H,
  • Fan JJ,
  • Yao YH,
  • Chai YH,
  • Hu SY

Journal volume & issue
Vol. Volume 9
pp. 7219 – 7225

Abstract

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Yixin Hu, Hailong He, Jun Lu, Yi Wang, Peifang Xiao, Jianqin Li, Jie Li, Yina Sun, Hui Lv, Junjie Fan, Yanhua Yao, Yihuan Chai, Shaoyan Hu Department of Hematology and Oncology, The Children’s Hospital of Soochow University, Suzhou, People’s Republic of China Objective: The objective of this study was to observe the prognosis of pediatric patients with E2A-PBX1-positive acute lymphoblastic leukemia (ALL) from the treatment with the CCLG-ALL2008 protocol.Design and methods: Three hundred and forty-nine Chinese pediatric patients with pre-B-cell ALL were enrolled in this study from December 2008 to September 2013. Of these, 20 patients with E2A-PBX1 expression and 223 without the gene expression were stratified into two cohorts. Clinical and biological characteristics and 5-year event-free survival (EFS), relapse-free survival (RFS), and overall survival (OS) were analyzed and compared between these two groups. Results: The E2A-PBX1 fusion transcript was detected in 20 of 349 (5.7%) patients. Compared with the gene-negative subgroup, patients with E2A-PBX1 were younger in age but did not show significant differences in white blood cell (WBC) count or gender distribution at primary diagnosis. Moreover, there were more inferior karyotypes detected in the E2A-PBX1 subgroup (P=0.035). With the CCLG-ALL2008 treatment protocol, patients with E2A-PBX1 showed a favorable treatment response with lower minimal residual disease (MRD) levels (<10-4) at time point 1 (TP1, P=0.039) but no superior steroid response or histological remission. We also observed a promising survival outcome, with a 5-year EFS reaching 95.0%±4.9% versus 66.3%±3.9% in the gene-negative group (P=0.039). However, we did not find significant differences in RFS (P=0.061) and OS (P=0.113).Conclusion: Our data provided clinical observation of Chinese pediatric patients. Patients with E2A-PBX1-positive ALL benefited well from the CCLG-ALL2008 protocol, a risk-based intensified treatment trial, with lower levels of MRD and longer RFS duration though they had no favorable characteristics at primary diagnosis. Keywords: pediatric, acute lymphoblastic leukemia, E2A-PBX1 gene transcript, prognosis, CCLG-ALL2008 protocol

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