Description
SOX11 (Sex determining region Y-box 11) expression is specific for MCL as compared to other Non-Hodgkin’s lymphomas. However, the function and direct binding targets of SOX11 in MCL are largely unknown. We used high-resolution ChIP-Seq to identify the direct target genes of SOX11 in a genome-wide, unbiased manner and elucidate its functional significance. Pathway analysis identified WNT, PKA and TGF-beta signaling pathways as significantly enriched by SOX11 target genes. qCHIP confirmed that SOX11 directly binds to individual genes in these pathways in both MCL cell lines and patients. Interrogation of an eighty-two patient gene-expression dataset demonstrated that SOX11 mRNA expression was inversely proportional to Ki-67, a marker of cell proliferation. Functional studies using RNA interference demonstrate that SOX11 directly regulates WNT signaling and modulates chemotherapy sensitivity to cytarabine in MCL. We analyzed SOX11 expression in three independent well-annotated tissue microarrays from the University of Wisconsin (UW), Karolina Institute and British Columbia Cancer Agency (BCCA). Our findings suggest that high SOX11 expression is associated with improved survival in a subset of MCL patients, particularly those treated with intensive chemotherapy incorporating cytarabine. Transcriptional regulation of WNT and other biological pathways affects by SOX11 target genes may help explain the impact of SOX11 expression on patient outcomes. Overall design: RNA-seq experiments studying SOX11-mediated regulation of gene transcription by examining genes differentially expressed following SOX11 depletion in 3 MCL cell lines, Granta-519, Z138 and JEKO-1