DNA methylation holds prognostic information in relapsed precursor B-cell acute lymphoblastic leukemia

To access publisher's full text version of this article, please click on the hyperlink in Additional Links field or click on the hyperlink at the top of the page marked FilesBACKGROUND: Few biological markers are associated with survival after relapse of B-cell precursor acute lymphoblastic leukemia (BCP-ALL). In pediatric T-cell ALL, we have identified promoter-associated methylation alterations that correlate with prognosis. Here, the prognostic relevance of CpG island methylation phenotype (CIMP) classification was investigated in pediatric BCP-ALL patients. METHODS: Six hundred and one BCP-ALL samples from Nordic pediatric patients (age 1-18) were CIMP classified at initial diagnosis and analyzed in relation to clinical data. RESULTS: Among the 137 patients that later relapsed, patients with a CIMP- profile (n = 42) at initial diagnosis had an inferior overall survival (pOS5years 33%) compared to CIMP+ patients (n = 95, pOS5years 65%) (p = 0.001), which remained significant in a Cox proportional hazards model including previously defined risk factors. CONCLUSION: CIMP classification is a strong candidate for improved risk stratification of relapsed BCP-ALL.Swedish Cancer Society Swedish Childhood Cancer Foundation Medical Faculty of Umea University Lion's Cancer Research Foundation Umea University Umea Pediatric Clinic Research Foundation Kempe foundations Magnus Bergvalls Foundation Uppsala-Umea Comprehensive Cancer Consortium Vasterbotten County Council Swedish Research Council Knut and Alice Wallenberg Foundatio