Comprehensive deciphering of the genetic, epigenetic and immunogenetic mechanisms of post-allogeneic transplant relapse in acute myeloid leukemia

It has become apparent that myeloid disorders may undergo changes in clonal structure with acquisition or loss of specific mutations, which may occur in response to pre-transplant chemotherapy (i.e. post-diagnosis) or due to immune pressures from the graft-versus-leukemia effect. A clone may be selected out that has a competitive advantage vs. the normal bone marrow cells which then grows unimpeded and ultimately leads to a full blown clinical relapse. In order to dissect clonal evolution in the post transplant setting it is necessary to study the genetic and epigenetic changes in the leukemic clone. Whole genome sequencing (WGS) allows the full assessment of shifts in the genetic landscape of the relapsing clone, and is advantageous over targeted sequencing which may miss potentially important regulatory regions which are not part of the targeted panel. Whole transcriptome (WT) analysis can provide more detailed information on the genes being expressed, by analyzing both coding and multiple forms of noncoding RNA for a comprehensive view of the transcriptome. WT analysis is complementary to WGS and will reveal potential transcriptome changes in leukemic cells which promote immune evasion, which is a common pathway for relapse post allogeneic stem cell transplant. Thus, this study will capture both known and novel features of the genomic and transcriptomic landscape in patients relapsed post allogeneic stem cell transplant.