Dataset Information

PML regulates PPAR signaling and fatty acid oxidation in breast cancer

ABSTRACT: Cancer cells exhibit an aberrant metabolism which facilitates more efficient production of biomass, and hence tumor growth and progression. The genetic cues modulating this metabolic switch remain largely undetermined, however. Here we identify a metabolic function for PML which reveals an unexpected role for this bona-fide tumor suppressor in pro-survival activity in breast cancer. We find that PML acts as both a negative regulator of PGC1A acetylation and as a potent activator of peroxisome proliferator-activated receptor (PPAR) signaling and fatty acid oxidation (FAO). We further show that as FAO PML promotes ATP production, inhibits anoikis, and allows luminal filling in 3D basement membrane breast culture models. Furthermore, analysis of breast cancer biopsies reveals that PML is over-expressed in a subset of breast cancers, and is enriched in triple-negative cases. Indeed, PML expression in breast cancer correlates strikingly with reduced time to recurrence, a gene signature of poor prognosis and activated PPAR signaling. These findings have important therapeutic implications, as PML and its key role in FAO metabolism are amenable to pharmacological suppression as a mode of cancer prevention and treatment.

ORGANISM(S): Mus musculus

PROVIDER: GSE39220 | GEO | 2013/01/29

SECONDARY ACCESSION(S): PRJNA170245

REPOSITORIES: GEO

ACCESS DATA

Similar Datasets

Project description:The alternative splicing of PML precursor mRNA gives rise to various PML isoforms, yet their expression profile in breast cancer cells remains uncharted. We discovered that PML1 is the most abundant isoform in all breast cancer subtypes, and its expression is associated with unfavorable prognosis in estrogen receptor-positive (ER+) breast cancers. PML depletion reduces cell proliferation, invasion, and stemness, while heterologous PML1 expression augments these processes and fuels tumor growth and resistance to fulvestrant, an FDA-approved drug for ER+ breast cancer, in a mouse model. Moreover, PML1, rather than the well-known tumor suppressor isoform PML4, rescues the proliferation of PML knockdown cells. ChIP-seq analysis reveals significant overlap between PML-, ER-, and Myc-bound promoters, suggesting their coordinated regulation of target gene expression, including genes involved in breast cancer stem cells (BCSCs), such as JAG1, KLF4, YAP1, SNAI1, and MYC. Loss of PML reduces BCSC-related gene expression, and exogenous PML1 expression elevates their expression. Consistently, PML1 restores the association of PML with these promoters in PML-depleted cells. We identified a novel association between PML1 and WDR5, a key component of H3K4 methyltransferase (HMTs) complexes that catalyze H3K4me1 and H3K4me3. ChIP-seq analyses showed that the loss of PML1 reduces H3K4me3 in numerous loci, including BCSC-associated gene promoters. Additionally, PML1, not PML4, re-establishes the H3K4me3 mark on these promoters in PML-depleted cells. Significantly, PML1 is essential for recruiting WDR5, MLL1, and MLL2 to these gene promoters. Inactivating WDR5 by knockdown or inhibitors phenocopies the effects of PML1 loss, reducing BCSC-related gene expression and tumorsphere formation and enhancing fulvestrant’s anticancer activity. Our findings challenge the conventional understanding of PML as a tumor suppressor, redefine its role as a promoter of tumor growth in breast cancer and offer new insights into the unique roles of PML isoforms in breast cancer.

Dataset Information

PML regulates PPAR signaling and fatty acid oxidation in breast cancer

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure