Somatic mutations of the histone H3K27 demethylase gene UTX in human cancer

Abstract

Somatically acquired epigenetic changes are present in many cancers. Epigenetic regulation is maintained via post-translational modifications of core histones. Here, we describe inactivating somatic mutations in the histone lysine demethylase gene UTX, pointing to histone H3 lysine methylation deregulation in multiple tumor types. UTX reintroduction into cancer cells with inactivating UTX mutations resulted in slowing of proliferation and marked transcriptional changes. These data identify UTX as a new human cancer gene.

Figure 1

1a) Western blot of samples showing lack of protein expression in UTX mutant samples.1b) Growth Effects of UTX reintroduction. Top panel -western blot confirmation of UTX expression in the transfected cell lines (UTX wildtype NCI-H1299, UTX null KYSE-180, 450). Bottom panel - significant cell doubling time increases in hours seen upon reintroduction of UTX wildtype in to UTX null lines but not in wildtype control cells. White bars- empty vector controls, grey bars – UTX reintroduction 1c) Specific reduction of H3K27me3 on genes showing differential expression after UTX introduction in KYSE180 (SOX21,PCDH19). Relative enrichment (fraction H3K27me3 bound DNA/input DNA) was quantified by real time PCR using primers against promoter regions of respective genes. Error bars represent the standard deviation from two independent transfection experiments. Primer sequences are given in supplementary Table 3. ACTB and APRT are negative controls for H3K27me3 marks and SFRP4 is a positive antibody control for H3K27me3. Controls are all taken from Schlesinger et al. White bars - empty vector control, grey bars -UTX reintroduction