Genome complexity in acute lymphoblastic leukemia is revealed by array-based comparative genomic hybridization

Chromosomal abnormalities are important for the classification and risk stratification of patients with acute lymphoblastic leukemia (ALL). However, approximately 30% of childhood and 50% of adult patients lack abnormalities with clinical relevance. Here, we describe the use of array-based comparative genomic hybridization (aCGH) to identify copy number alterations (CNA) in 58 ALL patients. CNA were identified in 83% of cases, and most frequently involved chromosomes 21 (n=42), 9 (n=21), 6 (n=16), 12 (n=11), 15 (n=11), 8 (n=10) and 17 (n=10). Deletions of 6q (del(6q)) were heterogeneous in size, in agreement with previous data, demonstrating the sensitivity of aCGH to measure CNA. Although 9p deletions showed considerable variability in both the extent and location, all encompassed the CDKN2A locus. Six patients showed del(12p), with a common region encompassing the ETV6 gene. Complex CNA were observed involving chromosomes 6 (n=2), 15 (n=2) and 21 (n=11) with multiple regions of loss and gain along each chromosome. Chromosome 21 CNA shared a common region of gain, with associated subtelomeric deletions. Other recurrent findings included dim(13q), dim(16q) and enh(17q). This is the first report of genome-wide detection of CNA in ALL patients using aCGH, and it has demonstrated a higher level of karyotype complexity than anticipated from conventional cytogenetic analysis

Methyl-Readers and Inhibitors

Due to their prevalent role in epigenetic gene regulation, methyllysine and methylarginine domain readers have emerged as potential drug targets for small-molecule intervention. Within this book chapter, the biological role and the associated development of potent small molecules inhibiting the protein-protein interaction of methyllysine readers (Tudor, malignant brain tumor, chromo-, and PHD domain) will be discussed. The druggability of these readers and thus their potential to serve as targets for small-molecule ligands will be evaluated critically. Those domains (PWWP, WD40, ankyrin repeats, and ADD domains) which are not yet targeted will be evaluated for their biological actions and eventual therapeutic implications. To sum up, a comprehensive review of the state of the art for all relevant methyl-readers and their inhibitors if present will be given from a medicinal chemistry standpoint of view