35 research outputs found
Correction to: VULCAN integrates ChIP-seq with patient-derived co-expression networks to identify GRHL2 as a key co-regulator of ERa at enhancers in breast cancer.
Following publication of the original article [1], the authors reported that Figs. 4 and 5 had mistakenly been transposed. Please find the correct Figs. 4 and 5 below. The original article [1] has been corrected
RNF40 regulates gene expression in an epigenetic context-dependent manner
Background Monoubiquitination of H2B (H2Bub1) is a largely enigmatic histone modification that has been linked to transcriptional elongation. Because of this association, it has been commonly assumed that H2Bub1 is an exclusively positively acting histone modification and that increased H2Bub1 occupancy correlates with increased gene expression. In contrast, depletion of the H2B ubiquitin ligases RNF20 or RNF40 alters the expression of only a subset of genes. Results Using conditional Rnf40 knockout mouse embryo fibroblasts, we show that genes occupied by low to moderate amounts of H2Bub1 are selectively regulated in response to Rnf40 deletion, whereas genes marked by high levels of H2Bub1 are mostly unaffected by Rnf40 loss. Furthermore, we find that decreased expression of RNF40-dependent genes is highly associated with widespread narrowing of H3K4me3 peaks. H2Bub1 promotes the broadening of H3K4me3 to increase transcriptional elongation, which together lead to increased tissue-specific gene transcription. Notably, genes upregulated following Rnf40 deletion, including Foxl2, are enriched for H3K27me3, which is decreased following Rnf40 deletion due to decreased expression of the Ezh2 gene. As a consequence, increased expression of some RNF40-“suppressed” genes is associated with enhancer activation via FOXL2. Conclusion Together these findings reveal the complexity and context-dependency whereby one histone modification can have divergent effects on gene transcription. Furthermore, we show that these effects are dependent upon the activity of other epigenetic regulatory proteins and histone modifications
Breast cancer bone metastases are attenuated in a Tgif1-deficient bone microenvironment.
BACKGROUND: Osteoclast activation is a hallmark of breast cancer-induced bone disease while little is known about the role of osteoblasts in this process. Recently, we identified the homeodomain protein TG-interacting factor-1 (Tgif1) as a crucial regulator of osteoblast function. In this study, we demonstrate that lack of Tgif1 also restricts the progression of breast cancer bone metastases. METHODS: Transwell migration assays were used to investigate the osteoblast-breast cancer cell interaction in vitro. Molecular analyses included RNA sequencing, immunoblotting, and qRT-PCR. To determine the role of Tgif1 in metastatic bone disease, 4T1 breast cancer cells were injected intracardially into mice with a germ line deletion of Tgif1 (Tgif1-/-) or control littermates (Tgif1+/+). Progression of bone metastases and alterations in the bone microenvironment were assessed using bioluminescence imaging, immunofluorescence staining, confocal microscopy, and histomorphometry. RESULTS: Medium conditioned by osteoblasts stimulated breast cancer cell migration, indicating a potential role of osteoblasts during bone metastasis progression. Tgif1 expression was strongly increased in osteoblasts upon stimulation by breast cancer cells, demonstrating the implication of Tgif1 in the osteoblast-breast cancer cell interaction. Indeed, conditioned medium from osteoblasts of Tgif1-/- mice failed to induce breast cancer cell migration compared to control, suggesting that Tgif1 in osteoblasts augments cancer cell motility. Semaphorin 3E (Sema3E), which is abundantly secreted by Tgif1-/- osteoblasts, dose-dependently reduced breast cancer cell migration while silencing of Sema3E expression in Tgif1-/- osteoblasts partially restored the impaired migration. In vivo, we observed a decreased number of breast cancer bone metastases in Tgif1-/- mice compared to control littermates. Consistently, the presence of single breast cancer cells or micro-metastases in the tibiae was reduced in Tgif1-/- mice. Breast cancer cells localized in close proximity to Endomucin-positive vascular cells as well as to osteoblasts. Although Tgif1 deficiency did not affect the bone marrow vasculature, the number and activity of osteoblasts were reduced compared to control. This suggests that the protective effect on bone metastases might be mediated by osteoblasts rather than by the bone marrow vasculature. CONCLUSION: We propose that the lack of Tgif1 in osteoblasts increases Sema3E expression and attenuates breast cancer cell migration as well as metastases formation
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Breast cancer bone metastases are attenuated in a Tgif1-deficient bone microenvironment.
BACKGROUND: Osteoclast activation is a hallmark of breast cancer-induced bone disease while little is known about the role of osteoblasts in this process. Recently, we identified the homeodomain protein TG-interacting factor-1 (Tgif1) as a crucial regulator of osteoblast function. In this study, we demonstrate that lack of Tgif1 also restricts the progression of breast cancer bone metastases. METHODS: Transwell migration assays were used to investigate the osteoblast-breast cancer cell interaction in vitro. Molecular analyses included RNA sequencing, immunoblotting, and qRT-PCR. To determine the role of Tgif1 in metastatic bone disease, 4T1 breast cancer cells were injected intracardially into mice with a germ line deletion of Tgif1 (Tgif1-/-) or control littermates (Tgif1+/+). Progression of bone metastases and alterations in the bone microenvironment were assessed using bioluminescence imaging, immunofluorescence staining, confocal microscopy, and histomorphometry. RESULTS: Medium conditioned by osteoblasts stimulated breast cancer cell migration, indicating a potential role of osteoblasts during bone metastasis progression. Tgif1 expression was strongly increased in osteoblasts upon stimulation by breast cancer cells, demonstrating the implication of Tgif1 in the osteoblast-breast cancer cell interaction. Indeed, conditioned medium from osteoblasts of Tgif1-/- mice failed to induce breast cancer cell migration compared to control, suggesting that Tgif1 in osteoblasts augments cancer cell motility. Semaphorin 3E (Sema3E), which is abundantly secreted by Tgif1-/- osteoblasts, dose-dependently reduced breast cancer cell migration while silencing of Sema3E expression in Tgif1-/- osteoblasts partially restored the impaired migration. In vivo, we observed a decreased number of breast cancer bone metastases in Tgif1-/- mice compared to control littermates. Consistently, the presence of single breast cancer cells or micro-metastases in the tibiae was reduced in Tgif1-/- mice. Breast cancer cells localized in close proximity to Endomucin-positive vascular cells as well as to osteoblasts. Although Tgif1 deficiency did not affect the bone marrow vasculature, the number and activity of osteoblasts were reduced compared to control. This suggests that the protective effect on bone metastases might be mediated by osteoblasts rather than by the bone marrow vasculature. CONCLUSION: We propose that the lack of Tgif1 in osteoblasts increases Sema3E expression and attenuates breast cancer cell migration as well as metastases formation
Pengembangan Kurikulum Pendidikan Lingkungan di Kota Tangerang Selatan: Bagaimana Mengintegrasikan Deklarasi Tbilisi dalam Kurikulum
This study aims to develop environmental education curriculum based on Tbilisi Declaration. There were five environmental education goals of Tbilisi Declaration namely knowledge, awareness, attitudes, skills, and participation. Curriculum was developed for supporting education policy in South Tangerang, Banten Province, Indonesia. Letter of Education Division South Tangerang City nomor 800/KEP 1222-dikdas/2014 stated environmental education as local curriculum in South Tangerang Elementary School. Curriculum was developed by developmental research. There was four steps to develop curriculum, every steps had three activities, i.e. making, reviewing, and fixing. This study result some standard and basic competences. Research developed environmental education was integrated with thematic subject matter in 1st and 2nd grade, but as monolithic subject matter in 3rd – 6rd grade. Using exiting competence standard from 2014 curriculum and format standard competence 2006 made this curriculum have flexibility to implement for the school that used 2006 or 2013 curriculum
An NFATc1/SMAD3/cJUN Complex Restricted to SMAD4-Deficient Pancreatic Cancer Guides Rational Therapies
Background & AimsThe highly heterogeneous cellular and molecular makeup of pancreatic ductal adenocarcinoma (PDAC) not only fosters exceptionally aggressive tumor biology, but contradicts the current concept of one-size-fits-all therapeutic strategies to combat PDAC. Therefore, we aimed to exploit the tumor biological implication and therapeutic vulnerabilities of a clinically relevant molecular PDAC subgroup characterized by SMAD4 deficiency and high expression of the nuclear factor of activated T cells (SMAD4–/–/NFATc1High).MethodsTranscriptomic and clinical data were analyzed to determine the prognostic relevance of SMAD4–/–/NFATc1High cancers. In vitro and in vivo oncogenic transcription factor complex formation was studied by immunoprecipitation, proximity ligation assays, and validated cross model and species. The impact of SMAD4 status on therapeutically targeting canonical KRAS signaling was mechanistically deciphered and corroborated by genome-wide gene expression analysis and genetic perturbation experiments, respectively. Validation of a novel tailored therapeutic option was conducted in patient-derived organoids and cells and transgenic as well as orthotopic PDAC models.ResultsOur findings determined the tumor biology of an aggressive and chemotherapy-resistant SMAD4–/–/NFATc1High subgroup. Mechanistically, we identify SMAD4 deficiency as a molecular prerequisite for the formation of an oncogenic NFATc1/SMAD3/cJUN transcription factor complex, which drives the expression of RRM1/2. RRM1/2 replenishes nucleoside pools that directly compete with metabolized gemcitabine for DNA strand incorporation. Disassembly of the NFATc1/SMAD3/cJUN complex by mitogen-activated protein kinase signaling inhibition normalizes RRM1/2 expression and synergizes with gemcitabine treatment in vivo to reduce the proliferative index.ConclusionsOur results suggest that PDAC characterized by SMAD4 deficiency and oncogenic NFATc1/SMAD3/cJUN complex formation exposes sensitivity to a mitogen-activated protein kinase signaling inhibition and gemcitabine combination therapy
IL6/STAT3 Signaling Hijacks Estrogen Receptor α Enhancers to Drive Breast Cancer Metastasis
H4K12ac is regulated by estrogen receptor-alpha and is associated with BRD4 function and inducible transcription
Hormone-dependent gene expression requires dynamic and coordinated epigenetic changes. Estrogen receptor-positive (ER(+)) breast cancer is particularly dependent upon extensive chromatin remodeling and changes in histone modifications for the induction of hormone-responsive gene expression. Our previous studies established an important role of bromodomain-containing protein-4 (BRD4) in promoting estrogen-regulated transcription and proliferation of ER(+) breast cancer cells. Here, we investigated the association between genome-wide occupancy of histone H4 acetylation at lysine 12 (H4K12ac) and BRD4 in the context of estrogen-induced transcription. Similar to BRD4, we observed that H4K12ac occupancy increases near the transcription start sites (TSS) of estrogen-induced genes as well as at distal ERα binding sites in an estrogen-dependent manner. Interestingly, H4K12ac occupancy highly correlates with BRD4 binding and enhancer RNA production on ERα-positive enhancers. Consistent with an importance in estrogen-induced gene transcription, H4K12ac occupancy globally increased in ER-positive cells relative to ER-negative cells and these levels were further increased by estrogen treatment in an ERα-dependent manner. Together, these findings reveal a strong correlation between H4K12ac and BRD4 occupancy with estrogen-dependent gene transcription and further suggest that modulators of H4K12ac and BRD4 may serve as new therapeutic targets for hormone-dependent cancers