Targeting the SIN3A-PF1 Interaction inhibits Epithelial to Mesenchymal Transition and Maintenance of a Stem Cell Phenotype in Triple Negative Breast Cancer (MNase-seq)

ABSTRACT: Triple negative breast cancer (TNBC) is characterized by a poorly differentiated phenotype and limited treatment options. Aberrant epigenetics in this subtype represent a potential therapeutic opportunity, but a better understanding of the mechanisms contributing to the TNBC pathogenesis is required. The SIN3 molecular scaffold performs a critical role in multiple cellular processes, including epigenetic regulation, and has been identified as a potential therapeutic target. Using a competitive peptide corresponding to the SIN3 interaction domain of MAD (Tat-SID), we investigated the functional consequences of selectively blocking the paired amphipathic helix (PAH2) domain of SIN3. Here, we report the identification of the SID-containing adaptor PF1 as a factor required for maintenance of the TNBC stem cell phenotype and epithelial to mesenchymal transition (EMT). Tat-SID peptide blocked the interaction between SIN3A and PF1, leading to epigenetic modulation and transcriptional downregulation of TNBC stem cell and EMT markers. Importantly, Tat-SID treatment led to a reduction in primary tumor growth and disseminated metastatic disease in vivo. In support of these findings, knockdown of PF1 expression phenocopied treatment with Tat-SID both in vitro and in vivo. These results demonstrate a critical role for a complex containing SIN3A and PF1 in TNBC and provide a rational for its therapeutic targeting. Mononucleosomes from MDA-MB-231 cells were isolated and ChIP with H3K4me3 antibody. DNA from Input and ChIP samples was purified and sequenced on Illumina Hiseq.

ORGANISM(S): Homo sapiens

SUBMITTER: Kevin Petrie 

PROVIDER: E-GEOD-73869 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress