Epigenetic Modifier Mutations in the LL-100 Panel

The NCI-60 human cell line panel, developed for use in drug development comprises sixty human cancer cell lines derived from nine different tissues. Only six cell lines of the NCI-60 were derived from blood cancers. Therefore, most forms and subtypes of leukemia and lymphoma are not represented in the NCI-60 panel. To respond to this apparent gap, we suggest the novel LL-100 panel, 100 leukemia and lymphoma cell lines representing the major leukemia/lymphoma entities, for basic research and drug development.

Whole exome sequencing and RNA sequencing were performed to identify mutations in 100 cell lines. Here we list the 100 cell lines, ordered by subtype and show mutations in epigenetic modifier genes.

We found cell lines with mutations in ASXL1, EZH2, IDH1, TET2 and in DNMT3A. Hitherto, cell line OCI-AML3 was the only human cell line described with a DNMT3A mutation. Twenty-two percent of patients with acute myeloid leukemia contain DNMT3A mutations and the median overall survival with DNMT3A mutations is shorter than without. Most DNMT3A mutations are heterozygous and alter amino acid R882, R882H being the most common DNMT3A mutation in AML. Exogenously mutant murine R878H (equivalent to human R882H) inhibits DNMT3A activity in a dominant negative manner. We describe here that the AML cell line SET-2 carries a heterozygous G to A transition at chr2_25234373 (hg38) which leads to the DNMT3A R882H amino acid substitution. Chip-based methylation analysis revealed that the described DNMT3A targets IRF8, KLF2, HOXA11 and HOXB2 are hypomethylated in cell lines OCI-AML3 (DNMT3A R882C) and in SET-2 (DNMT3A R882H). These data suggest that SET-2 is a novel model cell line for functional analysis of the DNMT3A R882 mutation and a first gain in knowledge through data mining the LL-100 panel.