PHF20L1 as a H3K27me2 reader coordinates with transcriptional repressors to promote breast tumorigenesis

TUDOR domain–containing proteins (TDRDs) are chiefly responsible for recognizing methyl-lysine/arginine residue. However, how TDRD dysregulation contributes to breast tumorigenesis is poorly understood. Here, we report that TUDOR domain–containing PHF20L1 as a H3K27me2 reader exerts transcriptional repression by recruiting polycomb repressive complex 2 (PRC2) and Mi-2/nucleosome remodeling and deacetylase (NuRD) complex, linking PRC2-mediated methylation and NuRD-mediated deacetylation of H3K27. Furthermore, PHF20L1 was found to serve as a potential MYC and hypoxia-driven oncogene, promoting glycolysis, proliferation, and metastasis of breast cancer cells by directly inhibiting tumor suppressors such as HIC1, KISS1, and BRCA1. PHF20L1 expression was also strongly correlated with higher histologic grades of breast cancer and markedly up-regulated in several cancers. Meanwhile, Phf20l1 deletion not only induces growth retardation and mammary ductal outgrowth delay but also inhibits tumorigenesis in vivo. Our data indicate that PHF20L1 promotes tumorigenesis, supporting the pursuit of PHF20L1 as a target for cancer therapy.

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Centrosome amplification: a suspect in breast cancer and racial disparities

Endocrine Related Cancer ◽

10.1530/erc-17-0072 ◽

2017 ◽

Vol 24 (9) ◽

pp. T47-T64 ◽

Cited By ~ 9

Author(s):

Angela Ogden ◽

Padmashree C G Rida ◽

Ritu Aneja

Keyword(s):

Breast Cancer ◽

Centrosome Amplification ◽

Breast Cancers ◽

Breast Tumorigenesis ◽

Breast Cancer Outcomes ◽

Clinically Significant ◽

Cellular Tolerance ◽

Cellular Phenotypes

The multifaceted involvement of centrosome amplification (CA) in tumorigenesis is coming into focus following years of meticulous experimentation, which have elucidated the powerful abilities of CA to promote cellular invasion, disrupt stem cell division, drive chromosomal instability (CIN) and perturb tissue architecture, activities that can accelerate tumor progression. Integration of the extantin vitro,in vivoand clinical data suggests that in some tissues CA may be a tumor-initiating event, in others a consequential ‘hit’ in multistep tumorigenesis, and in some others, non-tumorigenic. However,in vivodata are limited and primarily focus on PLK4 (which has CA-independent mechanisms by which it promotes aggressive cellular phenotypes).In vitrobreast cancer models suggest that CA can promote tumorigenesis in breast cancer cells in the setting of p53 loss or mutation, which can both trigger CA and promote cellular tolerance to its tendency to slow proliferation and induce aneuploidy. It is thus our perspective that CA is likely an early hit in multistep breast tumorigenesis that may sometimes be lost to preserve aggressive karyotypes acquired through centrosome clustering-mediated CIN, both numerical and structural. We also envision that the robust link between p53 and CA may underlie, to a considerable degree, racial health disparity in breast cancer outcomes. This question is clinically significant because, if it is true, then analysis of centrosomal profiles and administration of centrosome declustering drugs could prove highly efficacious in risk stratifying breast cancers and treating African American (AA) women with breast cancer.

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Dissecting genetic requirements of human breast tumorigenesis in a tissue transgenic model of human breast cancer in mice

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.0811785106 ◽

2009 ◽

Vol 106 (17) ◽

pp. 7022-7027 ◽

Cited By ~ 36

Author(s):

Min Wu ◽

Lina Jung ◽

Adrian B. Cooper ◽

Christina Fleet ◽

Lihao Chen ◽

...

Keyword(s):

Breast Cancer ◽

Targeted Therapies ◽

Human Breast Cancer ◽

Cancer Biology ◽

Genetic Alterations ◽

Genetically Engineered ◽

Human Breast ◽

Breast Tumorigenesis ◽

Preneoplastic Lesions

Breast cancer development is a complex pathobiological process involving sequential genetic alterations in normal epithelial cells that results in uncontrolled growth in a permissive microenvironment. Accordingly, physiologically relevant models of human breast cancer that recapitulate these events are needed to study cancer biology and evaluate therapeutic agents. Here, we report the generation and utilization of the human breast cancer in mouse (HIM) model, which is composed of genetically engineered primary human breast epithelial organoids and activated human breast stromal cells. By using this approach, we have defined key genetic events required to drive the development of human preneoplastic lesions as well as invasive adenocarcinomas that are histologically similar to those in patients. Tumor development in the HIM model proceeds through defined histological stages of hyperplasia, DCIS to invasive carcinoma. Moreover, HIM tumors display characteristic responses to targeted therapies, such as HER2 inhibitors, further validating the utility of these models in preclinical compound testing. The HIM model is an experimentally tractable human in vivo system that holds great potential for advancing our basic understanding of cancer biology and for the discovery and testing of targeted therapies.

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FOG-1 Directly Binds to a Chromatin Remodeling and Deacetylase-Containing Complex To Mediate Transcriptional Repression by GATA-1.

Blood ◽

10.1182/blood.v104.11.355.355 ◽

2004 ◽

Vol 104 (11) ◽

pp. 355-355

Author(s):

Wei Hong ◽

Minako Nakazawa ◽

Ying-Yu Chen ◽

Rajashree Kori ◽

Carrie Rakowski ◽

...

Keyword(s):

Transcriptional Repression ◽

Histone Deacetylation ◽

Gene Repression ◽

Single Point Mutation ◽

Mutant Form ◽

Erythroid Cells ◽

Binding Studies ◽

Nucleosome Remodeling ◽

N Terminus

Abstract Terminal erythroid maturation requires coordinated activation of erythroid marker genes and repression of genes associated with the undifferentiated state. These gene expression patterns are mediated by the concerted action of the erythroid transcription factor GATA-1 and its cofactor FOG-1 that can activate or repress transcription depending on promoter context. We and others showed previously that one mechanism by which FOG-1 functions is to facilitate GATA-1 association with certain DNA target sites in vivo. Using gene complementation studies of GATA-1-ablated erythroid cells, we show that at several GATA-1-repressed target genes (c-kit, c-myc and GATA-2) FOG-1 is dispensable for GATA-1 occupancy in vivo but essential for gene repression and histone deacetylation. To examine how FOG-1 functions as co-repressor we performed affinity chromatography, conventional protein purification and in vitro binding studies to identify proteins that bind FOG-1. We discovered that FOG-1 directly associates with the nucleosome remodeling and histone deacetylase complex NURD. This interaction is mediated by a small conserved domain at the N-terminus of FOG-1 and the MTA-1 subunit of NURD. Association of FOG-1 with NURD occurs in vivo and depends on an intact N-terminus of FOG-1. A series of point mutations across the N-terminus of FOG-1 revealed a tight correlation between NURD binding and transcriptional repression. In particular, a single point mutation at the N-terminus of FOG-1 that abrogated NURD binding also blocked gene repression by FOG-1. Finally, the ability of GATA-1 to repress transcription was impaired in erythroid cells expressing a mutant form of FOG-1 that is defective for NURD binding. Together, these studies show that FOG-1 and very likely other FOG proteins are bona fide co-repressors that link GATA proteins to histone deacetylation and nucleosome remodeling via a novel protein interaction module.

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Modulation of Chromatin Boundary Activities by Nucleosome-Remodeling Activities in Drosophila melanogaster

Molecular and Cellular Biology ◽

10.1128/mcb.00183-09 ◽

2009 ◽

Vol 30 (4) ◽

pp. 1067-1076 ◽

Cited By ~ 19

Author(s):

Mo Li ◽

Vladimir E. Belozerov ◽

Haini N. Cai

Keyword(s):

Drosophila Melanogaster ◽

Nucleosome Occupancy ◽

Boundary Function ◽

Higher Order ◽

Chromatin Organization ◽

Nurd Complex ◽

Nucleosome Remodeling ◽

Chromatin Boundary ◽

Enhancer Blocking

ABSTRACT Chromatin boundaries facilitate independent gene regulation by insulating genes from the effects of enhancers or organized chromatin. However, the mechanisms of boundary action are not well understood. To investigate whether boundary function depends on a higher order of chromatin organization, we examined the function of several Drosophila melanogaster insulators in cells with reduced chromatin-remodeling activities. We found that knockdown of NURF301 and ISWI, key components of the nucleosome-remodeling factor (NURF), synergistically disrupted the enhancer-blocking function of Fab7 and SF1 and augmented the function of Fab8. Mutations in Nurf301/Ebx and Iswi also affected the function of these boundaries in vivo. We further show that ISWI was localized on the endogenous Fab7 and Fab8 insulators and that NURF knockdown resulted in a marked increase in the nucleosome occupancy at these insulator sites. In contrast to the effect of NURF knockdown, reduction in dMi-2, the ATPase component of the Drosophila nucleosome-remodeling and deacetylation (NuRD) complex, augmented Fab7 and suppressed Fab8. Our results provide the first evidence that higher-order chromatin organization influences the enhancer-blocking activity of chromatin boundaries. In particular, the NURF and NuRD nucleosome-remodeling complexes may regulate Hox expression by modulating the function of boundaries in these complexes. The unique responses by different classes of boundaries to changes in the chromatin environment may be indicative of their distinct mechanisms of action, which may influence their placement in the genome and selection during evolution.

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CircPLK1 sponges miR-296-5p to facilitate triple-negative breast cancer progression

Epigenomics ◽

10.2217/epi-2019-0093 ◽

2019 ◽

Vol 11 (10) ◽

pp. 1163-1176 ◽

Cited By ~ 16

Author(s):

Yanan Kong ◽

Lu Yang ◽

Weidong Wei ◽

Ning Lyu ◽

Yutian Zou ◽

...

Keyword(s):

Breast Cancer ◽

Cancer Progression ◽

Triple Negative Breast Cancer ◽

Triple Negative ◽

Expression Profiles ◽

Proliferation And Metastasis ◽

Underlying Mechanisms

Aim: To investigate the role of circRNAs in triple-negative breast cancer (TNBC) and the underlying mechanisms. Materials & methods: We performed circRNA microarrays to explore the expression profiles of TNBC cell lines. Experiments in vitro and in vivo were conducted to explore the effects of circPLK1 on tumor proliferation and metastasis as well as the interaction between circPLK1, miR-296-5p and PLK1 in TNBC. Results & conclusion: CircPLK1 was significantly upregulated in TNBC and associated with poor survivals. CircPLK1 knockdown inhibited cell growth and invasion in vitro as well as tumor occurrence and metastasis in vivo. CircPLK1-miR-296-5p- PLK1 axis regulates tumor progression by ceRNA mechanism in TNBC, indicating that circPLK1 may serve as a prognostic factor and novel therapeutic target for TNBC.

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Transcriptional repression of VEGF by ZNF24: mechanistic studies and vascular consequences in vivo

Blood ◽

10.1182/blood-2012-05-433045 ◽

2013 ◽

Vol 121 (4) ◽

pp. 707-715 ◽

Cited By ~ 15

Author(s):

Di Jia ◽

Sean M. Hasso ◽

Joanne Chan ◽

Domenic Filingeri ◽

Patricia A. D'Amore ◽

...

Keyword(s):

Breast Cancer ◽

Transcriptional Repression ◽

Human Breast Cancer ◽

Zinc Finger Protein ◽

Negative Regulator ◽

Proximal Promoter ◽

Transgenic Zebrafish ◽

Human Breast ◽

In Vivo Models

Abstract VEGF is a key regulator of normal and pathologic angiogenesis. Although many trans-activating factors of VEGF have been described, the transcriptional repression of VEGF remains much less understood. We have previously reported the identification of a SCAN domain–containing C2H2 zinc finger protein, ZNF24, that represses the transcription of VEGF. In the present study, we identify the mechanism by which ZNF24 represses VEGF transcription. Using reporter gene and electrophoretic mobility shift assays, we identify an 11-bp fragment of the proximal VEGF promoter as the ZNF24-binding site that is essential for ZNF24-mediated repression. We demonstrate in 2 in vivo models the potent inhibitory effect of ZNF24 on the vasculature. Expression of human ZNF24 induced in vivo vascular defects consistent with those induced by VEGF knockdown using a transgenic zebrafish model. These defects could be rescued by VEGF overexpression. Overexpression of ZNF24 in human breast cancer cells also inhibited tumor angiogenesis in an in vivo tumor model. Analyses of human breast cancer tissues showed that ZNF24 and VEGF levels were inversely correlated in malignant compared with normal tissues. These data demonstrate that ZNF24 represses VEGF transcription through direct binding to an 11-bp fragment of the VEGF proximal promoter and that it functions as a negative regulator of tumor growth by inhibiting angiogenesis.

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MBD3L1 Is a Transcriptional Repressor That Interacts with Methyl-CpG-binding Protein 2 (MBD2) and Components of the NuRD Complex

Journal of Biological Chemistry ◽

10.1074/jbc.m409149200 ◽

2004 ◽

Vol 279 (50) ◽

pp. 52456-52464 ◽

Cited By ~ 42

Author(s):

Chun-Ling Jiang ◽

Seung-Gi Jin ◽

Gerd P. Pfeifer

Keyword(s):

Transcriptional Repression ◽

Binding Protein ◽

Transcriptional Repressor ◽

Binding Domain ◽

Nurd Complex ◽

Methylated Dna ◽

Binding Domains ◽

Mouse Cells

Methyl-CpG-binding domain proteins 2 and 3 (MBD2 and MBD3) are transcriptional repressors that contain methyl-CpG binding domains and are components of a CpG-methylated DNA binding complex named MeCP1. Methyl-CpG-binding protein 3-like 1 (MBD3L1) is a protein with substantial homology to MBD2 and MBD3, but it lacks the methyl-CpG binding domain. MBD3L1 interacts with MBD2 and MBD3in vitroand in yeast two-hybrid assays. Gel shift experiments with a CpG-methylated DNA probe indicate that recombinant MBD3L1 can supershift an MBD2-methylated DNA complex.In vivo, MBD3L1 associates with and colocalizes with MBD2 but not with MBD3 and is recruited to 5-methylcytosine-rich pericentromeric heterochromatin in mouse cells. In glutathioneS-transferase pull-down assays MBD3L1 is found associated with several known components of the MeCP1·NuRD complex, including HDAC1, HDAC2, MTA2, MBD2, RbAp46, and RbAp48, but MBD3 is not found in the MBD3L1-bound fraction. MBD3L1 enhances transcriptional repression of methylated DNA by MBD2. The data are consistent with a role of MBD3L1 as a methylation-dependent transcriptional repressor that may interchange with MBD3 as an MBD2-interacting component of the NuRD complex. MBD3L1 knockout mice were created and were found to be viable and fertile, indicating that MBD3L1 may not be essential or there is functional redundancy (through MBD3) in this pathway. Overall, this study reveals additional complexities in the mechanisms of transcriptional repression by the MBD family proteins.

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Identification of MFGE8 and KLK5/7 as mediators of breast tumorigenesis and resistance to COX-2 inhibition

Breast Cancer Research ◽

10.1186/s13058-021-01401-2 ◽

2021 ◽

Vol 23 (1) ◽

Author(s):

Jun Tian ◽

Vivian Wang ◽

Ni Wang ◽

Baharak Khadang ◽

Julien Boudreault ◽

...

Keyword(s):

Breast Cancer ◽

Molecular Mechanisms ◽

Gene Knockout ◽

In Silico Analysis ◽

Breast Tumorigenesis ◽

Clinical Benefits ◽

Cox 2 ◽

Cox 2 Inhibitors

Abstract Background Cyclooxygenase 2 (COX-2) promotes stemness in triple negative breast cancer (TNBC), highlighting COX-2 as a promising therapeutic target in these tumors. However, to date, clinical trials using COX-2 inhibitors in breast cancer only showed variable patient responses with no clear significant clinical benefits, suggesting underlying molecular mechanisms contributing to resistance to COX-2 inhibitors. Methods By combining in silico analysis of human breast cancer RNA-seq data with interrogation of public patient databases and their associated transcriptomic, genomic, and clinical profiles, we identified COX-2 associated genes whose expression correlate with aggressive TNBC features and resistance to COX-2 inhibitors. We then assessed their individual contributions to TNBC metastasis and resistance to COX-2 inhibitors, using CRISPR gene knockout approaches in both in vitro and in vivo preclinical models of TNBC. Results We identified multiple COX-2 associated genes (TPM4, RGS2, LAMC2, SERPINB5, KLK7, MFGE8, KLK5, ID4, RBP1, SLC2A1) that regulate tumor lung colonization in TNBC. Furthermore, we found that silencing MFGE8 and KLK5/7 gene expression in TNBC cells markedly restored sensitivity to COX-2 selective inhibitor both in vitro and in vivo. Conclusions Together, our study supports the establishment and use of novel COX-2 inhibitor-based combination therapies as future strategies for TNBC treatment.

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CPT1A and fatty acid β-oxidation are essential for tumor cell growth and survival in hormone receptor-positive breast cancer

NAR Cancer ◽

10.1093/narcan/zcab035 ◽

2021 ◽

Vol 3 (3) ◽

Author(s):

Nidhi Jariwala ◽

Gaurav A Mehta ◽

Vrushank Bhatt ◽

Shaimaa Hussein ◽

Kimberly A Parker ◽

...

Keyword(s):

Breast Cancer ◽

Fatty Acid ◽

Hormone Receptor ◽

Luminal Breast Cancer ◽

Acid Oxidation ◽

Breast Tumorigenesis ◽

Cancer Proliferation ◽

Hormone Receptor Positive

Abstract Chromosome 11q13-14 amplification is a defining feature of high-risk hormone receptor-positive (HR+) breast cancer; however, the mechanism(s) by which this amplicon contributes to breast tumorigenesis remains unclear. In the current study, proteogenomic analyses of >3000 breast tumors from the TCGA, METABRIC and CPTAC studies demonstrated that carnitine palmitoyltransferase 1A (CPT1A), which is localized to this amplicon, is overexpressed at the mRNA and protein level in aggressive luminal tumors, strongly associated with indicators of tumor proliferation and a predictor of poor prognosis. In vitro genetic studies demonstrated that CPT1A is required for and can promote luminal breast cancer proliferation, survival, as well as colony and mammosphere formation. Since CPT1A is the rate-limiting enzyme during fatty acid oxidation (FAO), our data indicate that FAO may be essential for these tumors. Pharmacologic inhibition of FAO prevented in vitro and in vivo tumor growth and cell proliferation as well as promoted apoptosis in luminal breast cancer cells and orthotopic xenograft tumor models. Collectively, our data establish an oncogenic role for CPT1A and FAO in HR+ luminal tumors and provide preclinical evidence and rationale supporting further investigation of FAO as a potential therapeutic opportunity for the treatment of HR+ breast cancer.

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Elevated Expression of The Rhythm Gene NFIL3 Promotes The Progression of TNBC By Activating NF-κB Signaling Through Suppression of NFKBIA Transcription

10.21203/rs.3.rs-968591/v1 ◽

2021 ◽

Author(s):

Wei-Wei Yang ◽

Jing Li ◽

Minghui Zhang ◽

Haichuan Yu ◽

Yuan Zhuang ◽

...

Keyword(s):

Breast Cancer ◽

Cancer Progression ◽

Epidemiological Studies ◽

Tumor Formation ◽

Cell Counting ◽

Aberrant Expression ◽

Functional Studies ◽

Proliferation And Metastasis

Abstract Background: Epidemiological studies have confirmed that abnormal circadian rhythms are associated with tumorigenesis in breast cancer. However, few studies have investigated the pathological roles of rhythm genes in breast cancer progression. Methods: The expressions of NFIL3 and NFKBIA were measured by Western blot, qRT–PCR and IHC analysis. The proliferation and metastasis of two TNBC cell lines were analyzed by cell counting assays, clone formation assays, subcutaneous tumor formation assay, wound healing assays, transwell assays and the mouse tail vein injection model.Results: We evaluated the aberrant expression of 32 rhythm genes in breast cancer and identified that nuclear factor interleukin 3 regulated (NFIL3) expression is significantly altered in triple-negative breast cancer (TNBC). We found that NFIL3 inhibits its own transcription, and thus, downregulated NFIL3 mRNA indicates high expression of NFIL3 protein in breast cancer. Functional studies demonstrated that NFIL3 promotes the proliferation and metastasis of TNBC cells in vitro and in vivo. Higher expression of NFIL3 is associated with poor prognosis of patients with TNBC. Gene enrichment assays revealed that NFIL3 primarily regulates cancer-associated inflammation. Correlation analysis showed that expression of NFIL3 is associated with infiltration level of various immune cells in breast cancer. We further demonstrated that NFIL3 enhances the activity of NF-κB signaling. Mechanistically, we revealed that NFIL3 directly suppresses the transcription of NFKBIA, which blocks the activation of NF-κB and inhibits the progression of TNBC cells in vitro and in vivo. Moreover, we showed that enhancing NF-κB activity by repressing NFKBIA largely mimics the oncogenic effect of NFIL3 in TNBC, and anti-inflammatory strategies targeting NF-κB activity block the oncogenic roles of NFIL3 in TNBC. Conclusion:NFIL3 promotes the progression of TNBC by suppressing NFKBIA and then enhancing NF-κB signaling-mediated cancer-associated inflammation. This study may provide a new target for TNBC prevention and therapy.

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