PDF file 316K, Supplementary Figure S1: Both hSETD1A and hSETD1B are up-regulated in human CRC. Supplementary Figure S2: hSETD1A modulates H3K4me3 levels and controls cellular growth. Supplementary Figure S3: The loss of hSETD1A does not induce apoptosis. Supplementary Figure S4: The loss of hSETD1A decreases H3K4me3 enrichment at the Wnt target gene promoters in CRC. Supplementary Figure S5: hSETD1A and TAF3 share a subset of key Wnt target genes. Supplementary Tables: Supplementary Table S1: Expression profile of Wnt target genes in shSETD1A HCT116 cells. Supplementary Table S2: Human ChIP primers used in this study. Supplementary Table S3: Human RT-PCT primers used in this study. Supplementary Table S4: Human shRNA used in this study
ARTICLE ABSTRACT
hSETD1A is a member of the trithorax (TrxG) family of histone methyltransferases (HMT) that methylate H3K4 at promoters of active genes. Although misregulation of mixed lineage leukemia (MLL) family proteins has been associated with acute leukemia, the role of hSETD1A in cancer remains unknown. In this study, we report that hSETD1A and its associated H3K4me3 are upregulated in human colorectal cancer cells and patient samples. Depletion of hSETD1A inhibits colorectal cancer cell growth, colony formation, and tumor engraftment. Genome-wide expression profiling of colorectal cancer cells reveals that approximately 50% of Wnt/β-catenin target genes are affected by the hSETD1A knockdown. We further demonstrate that hSETD1A is recruited to promoters of those Wnt signaling target genes through its interaction with β-catenin, a master regulator of the Wnt signaling pathway. The recruitment of the hSETD1A HMT complex confers promoter-associated H3K4me3 that leads to assembly of transcription preinitiation complex and transcriptional activation. Furthermore, the expression levels of hSETD1A are positively correlated with H3K4me3 enrichment at the promoters of Wnt/β-catenin target genes and the aberrant activation of these genes in human colorectal cancer. These results provide new biologic and mechanistic insights into the cooperative role of hSETD1A and β-catenin in regulation of Wnt target genes as well as in colorectal cancer cell growth in vitro and in vivo. Cancer Res; 74(3); 775–86. ©2013 AACR.
