| 1. |
- Raja, Erna, et al.
(författare)
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The protein kinase LKB1 negatively regulates bone morphogenetic protein receptor signaling
- 2016
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Ingår i: Oncotarget. - : Impact Journals, LLC. - 1949-2553. ; 7:2, s. 1120-1143
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Tidskriftsartikel (refereegranskat)abstract
- The protein kinase LKB1 regulates cell metabolism and growth and is implicated in intestinal and lung cancer. Bone morphogenetic protein (BMP) signaling regulates cell differentiation during development and tissue homeostasis. We demonstrate that LKB1 physically interacts with BMP type I receptors and requires Smad7 to promote downregulation of the receptor. Accordingly, LKB1 suppresses BMP-induced osteoblast differentiation and affects BMP signaling in Drosophila wing longitudinal vein morphogenesis. LKB1 protein expression and Smad1 phosphorylation analysis in a cohort of non-small cell lung cancer patients demonstrated a negative correlation predominantly in a subset enriched in adenocarcinomas. Lung cancer patient data analysis indicated strong correlation between LKB1 loss-of-function mutations and high BMP2 expression, and these two events further correlated with expression of a gene subset functionally linked to apoptosis and migration. This new mechanism of BMP receptor regulation by LKB1 has ramifications in physiological organogenesis and disease.
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| 2. |
- Thakur, Noopur, et al.
(författare)
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TGF beta-induced invasion of prostate cancer cells is promoted by c-Jun-dependent transcriptional activation of Snail1
- 2014
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Ingår i: Cell Cycle. - : Informa UK Limited. - 1538-4101 .- 1551-4005. ; 13:15, s. 2400-2414
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Tidskriftsartikel (refereegranskat)abstract
- High levels of transforming growth factor-beta (TGF beta) correlate with poor prognosis for patients with prostate cancer and other cancers. TGF beta is a multifunctional cytokine and crucial regulator of cell fate, such as epithelial to mesenchymal transition (EMT), which is implicated in cancer invasion and progression. TGF beta conveys its signals upon binding to type I and type II serine/threonine kinase receptors (T beta RI/II); phosphorylation of Smad2 and Smad3 promotes their association with Smad4, which regulates expression of targets genes, such as Smad7, p21, and c-Jun. TGF beta also activates the ubiquitin ligase tumor necrosis factor receptor-associated factor 6 (TRAF6), which associates with T beta RI and activates the p38 mitogen-activated protein kinase (MAPK) pathway. Snail1 is a key transcription factor, induced by TGF beta that promotes migration and invasion of cancer cells. In this study, we have identified a novel binding site for c-Jun in the promoter of the Snail1 gene and report that the activation of the TGF beta-TRAF6-p38 MAPK pathway promotes both c-Jun expression and its activation via p38a-dependent phosphorylation of c-Jun at Ser63. The TRAF6-dependent activation of p38 also leads to increased stability of c-Jun, due to p38-dependent inactivation of glycogen synthase kinase (GSK) 3 beta by phosphorylation at Ser9. Thus, our findings elucidate a novel role for the p38 MAPK pathway in stimulated cells, leading to activation of c-Jun and its binding to the promoter of Snail1, thereby triggering motility and invasiveness of aggressive human prostate cancer cells.
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| 3. |
- Carthy, Jon M., et al.
(författare)
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Tamoxifen Inhibits TGF-beta-Mediated Activation of Myofibroblasts by Blocking Non-Smad Signaling Through ERK1/2
- 2015
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Ingår i: Journal of Cellular Physiology. - : Wiley. - 0021-9541 .- 1097-4652. ; 230:12, s. 3084-3092
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Tidskriftsartikel (refereegranskat)abstract
- Transforming growth factor-beta (TGF-beta) is a multifunctional cytokine which stimulates the differentiation of fibroblasts into myofibroblasts. Myofibroblasts are critical for normal wound healing, but also accumulate pathologically in a number of chronic inflammatory conditions where they are key contributors to aberrant tissue remodeling and fibrosis, and in cancer stroma. In the current study, we identified a role for tamoxifen as a potent inhibitor of the TGF-beta-mediated activation of primary human skin and breast fibroblasts. Our data indicate that tamoxifen does not interfere with canonical Smad signaling downstream of TGF-beta but rather blocks non-Smad signaling through ERK1/2 MAP-kinase and the AP-1 transcription factor FRA2. We further demonstrate by siRNA-mediated knockdown that FRA2 is critical for the induced expression of myogenic proteins in response to TGF-beta. Functionally, TGF-beta-stimulated fibroblast-mediated contraction of collagen gels was impaired in the presence of tamoxifen. Altogether, these data demonstrate that tamoxifen prevents myofibroblast differentiation and, therefore, may provide therapeutic benefits to patients suffering from chronic inflammatory conditions or cancer.
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| 4. |
- Dadras, Mahsa Shahidi, et al.
(författare)
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The polarity protein Par3 coordinates positively self-renewal and negatively invasiveness in glioblastoma
- 2021
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Ingår i: Cell Death and Disease. - : Springer Nature. - 2041-4889. ; 12:10
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Tidskriftsartikel (refereegranskat)abstract
- Glioblastoma (GBM) is a brain malignancy characterized by invasiveness to the surrounding brain tissue and by stem-like cells, which propagate the tumor and may also regulate invasiveness. During brain development, polarity proteins, such as Par3, regulate asymmetric cell division of neuro-glial progenitors and neurite motility. We, therefore, studied the role of the Par3 protein (encoded by PARD3) in GBM. GBM patient transcriptomic data and patient-derived culture analysis indicated diverse levels of expression of PARD3 across and independent from subtypes. Multiplex immunolocalization in GBM tumors identified Par3 protein enrichment in SOX2-, CD133-, and NESTIN-positive (stem-like) cells. Analysis of GBM cultures of the three subtypes (proneural, classical, mesenchymal), revealed decreased gliomasphere forming capacity and enhanced invasiveness upon silencing Par3. GBM cultures with suppressed Par3 showed low expression of stemness (SOX2 and NESTIN) but higher expression of differentiation (GFAP) genes. Moreover, Par3 silencing reduced the expression of a set of genes encoding mitochondrial enzymes that generate ATP. Accordingly, silencing Par3 reduced ATP production and concomitantly increased reactive oxygen species. The latter was required for the enhanced migration observed upon silencing of Par3 as anti-oxidants blocked the enhanced migration. These findings support the notion that Par3 exerts homeostatic redox control, which could limit the tumor cell-derived pool of oxygen radicals, and thereby the tumorigenicity of GBM.
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| 5. |
- Fukuda, Tomohiko, et al.
(författare)
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BMP signaling is a therapeutic target in ovarian cancer
- 2020
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Ingår i: Cell Death Discovery. - : Springer Science and Business Media LLC. - 2058-7716. ; 6:1
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Tidskriftsartikel (refereegranskat)abstract
- BMP signaling has been found to have tumor-promoting as well as tumor-suppressing effects in different types of tumors. In this study, we investigated the effects of BMP signaling and of BMP inhibitors on ovarian cancer (OC) cells in vitro and in vivo. High expression of BMP receptor 2 (BMPR2) correlated with poor overall survival of OC patients in the TCGA dataset. Both BMP2 and BMPR2 enhanced OC cell proliferation, whereas BMP receptor kinase inhibitors inhibited OC cell growth in cell culture as well as in a mouse model. BMP2 also augmented sphere formation, migration, and invasion of OC cells, and induced EMT. High BMP2 expression was observed after chemotherapy of OC patients in the GSE109934 dataset. In accordance, carboplatin, used for the treatment of OC patients, increased BMP2 secretion from OC cells, and induced EMT partially via activation of BMP signaling. Our data suggest that BMP signaling has tumor-promoting effects in OC, and that BMP inhibitors might be useful therapeutic agents for OC patients. Considering that carboplatin treatment augmented BMP2 secretion, the possibility to use a combination of BMP inhibitors and carboplatin in the treatment of OC patients, would be worth exploring.
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| 6. |
- Fukuda, Tomohiko, et al.
(författare)
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BMP2-induction of FN14 promotes protumorigenic signaling in gynecologic cancer cells
- 2021
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Ingår i: Cellular Signalling. - : Elsevier. - 0898-6568 .- 1873-3913. ; 87
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Tidskriftsartikel (refereegranskat)abstract
- We previously reported that bone morphogenetic protein (BMP) signaling promotes tumorigenesis in gynecologic cancer cells. BMP2 enhances proliferation of ovarian and endometrial cancer cells via c-KIT induction, and triggers epithelial-mesenchymal transition (EMT) by SNAIL and/or SLUG induction, leading to increased cell migration. However, the downstream effectors of BMP signaling in gynecological cancer cells have not been clearly elucidated. In this study, we performed RNA-sequencing of Ishikawa endometrial and SKOV3 ovarian cancer cells after BMP2 stimulation, and identified TNFRSF12A, encoding fibroblast growth factor-inducible 14 (FN14) as a common BMP2-induced gene. FN14 knockdown suppressed BMP2-induced cell proliferation and migration, confirmed by MTS and scratch assays, respectively. In addition, FN14 silencing augmented chemosensitivity of SKOV3 cells. As a downstream effector of BMP signaling, FN14 modulated both c-KIT and SNAIL expression, which are important for growth and migration of ovarian and endometrial cancer cells. These results support the notion that the tumor promoting effects of BMP signaling in gynecological cancers are partially attributed to FN14 induction.
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| 7. |
- Karalis, Theodoros, et al.
(författare)
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Identification of a Small Molecule Inhibitor of Hyaluronan Synthesis, DDIT, Targeting Breast Cancer Cells
- 2022
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Ingår i: Cancers. - : MDPI. - 2072-6694. ; 14:23
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Tidskriftsartikel (refereegranskat)abstract
- Simple Summary The most aggressive subtype of breast cancer, triple-negative breast cancer, is characterized by an excessive accumulation of hyaluronan in the cancer and its peritumoral stroma, which has been linked to poor prognosis of the patients. Inhibitors of hyaluronan synthesis would thus have a potential clinical value. We have identified the thymidine analog 5 '-Deoxy-5 '-(1,3-Diphenyl-2-Imidazolidinyl)-Thymidine (DDIT) as a new non-toxic inhibitor of hyaluronan synthesis. DDIT is more potent than the available inhibitor 4-Methylumbelliferone (4-MU), and significantly suppressed the aggressiveness of triple-negative breast cancer cells grown in tissue culture. Breast cancer is a common cancer in women. Breast cancer cells synthesize large amounts of hyaluronan to assist their proliferation, survival, migration and invasion. Accumulation of hyaluronan and overexpression of its receptor CD44 and hyaluronidase TMEM2 in breast tumors correlate with tumor progression and reduced overall survival of patients. Currently, the only known small molecule inhibitor of hyaluronan synthesis is 4-methyl-umbelliferone (4-MU). Due to the importance of hyaluronan for breast cancer progression, our aim was to identify new, potent and chemically distinct inhibitors of its synthesis. Here, we report a new small molecule inhibitor of hyaluronan synthesis, the thymidine analog 5 '-Deoxy-5 '-(1,3-Diphenyl-2-Imidazolidinyl)-Thymidine (DDIT). This compound is more potent than 4-MU and displays significant anti-tumorigenic properties. Specifically, DDIT inhibits breast cancer cell proliferation, migration, invasion and cancer stem cell self-renewal by suppressing HAS-synthesized hyaluronan. DDIT appears as a promising lead compound for the development of inhibitors of hyaluronan synthesis with potential usefulness in breast cancer treatment.
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| 8. |
- Kolliopoulos, Constantinos, et al.
(författare)
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Has2 natural antisense RNA and Hmga2 promote Has2 expression during TGFβ-induced EMT in breast cancer
- 2019
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Ingår i: Matrix Biology. - : Elsevier BV. - 0945-053X .- 1569-1802. ; 80, s. 29-45
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Tidskriftsartikel (refereegranskat)abstract
- The glycosaminoglycan hyaluronan has a crucial role in tissue organization and cell signaling. Hyaluronan accumulates in conjunction with rapid tissue remodeling during embryogenesis, as well as in inflammatory conditions and cancer. We report a negative correlation between the expression of genes encoding hyaluronan synthase HAS2, its natural antisense transcript HAS2-AS, the chromatin modulating factor HMGA2 and transforming growth factor-β (TGFβ), and survival of patients with invasive breast carcinomas. In mouse mammary epithelial cells, TGFβ activates Smad and non-Smad signaling pathways, resulting in the transcriptional induction of Has2, Has2as (the mouse ortholog of HAS2-AS) and Hmga2, as well as epithelial-mesenchymal transition (EMT)-promoting transcription factors, such as Snail. Importantly, Has2as abrogation suppressed the TGFβ induction of EMT markers, including Snai1, Hmga2, Fn1, and suppressed the mesenchymal phenotype. TGFβ induction of Hmga2, Has2as and Has2, and synthesis of hyaluronan were accompanied with activation of Akt and Erk1/2 MAP-kinase signaling and were required for breast cancer cell motility. Importantly, the hyaluronan receptor Cd44, but not Hmmr, was required for TGFβ-mediated EMT phenotype. Interestingly, Has2as was found to contribute to the maintenance of stem cell factors and breast cancer stemness. Our findings show that Has2as has a key role in TGFβ- and HAS2-induced breast cancer EMT, migration and acquisition of stemness.
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| 9. |
- Lin, Chun-Yu, et al.
(författare)
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High levels of serum hyaluronan is an early predictor of dengue warning signs and perturbs vascular integrity
- 2019
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Ingår i: EBioMedicine. - : ELSEVIER. - 2352-3964. ; 48, s. 425-441
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Tidskriftsartikel (refereegranskat)abstract
- Background: A main pathological feature of severe dengue virus infection is endothelial hyper-permeability. The dengue virus nonstructural protein 1 (NS1) has been implicated in the vascular leakage that characterizes severe dengue virus infection, however, the molecular mechanisms involved are not known.Methods: A cohort of 250 dengue patients has been followed from the onset of symptoms to the recovery phase. Set urn hyaluronan levels and several other clinical parameters were recorded. The effect of NS1 treatment of cultured fibroblasts and endothelial cells on the expressions of hyaluronan synthetic and catabolic enzymes and the hyaluronan receptor CD44, were determined, as have the effects on the formation of hyaluronan-rich matrices and endothelial permeability.Findings: Elevated serum hyaluronan levels (70 ng/ml) during early infection was found to be an independent predictor for occurrence of warning signs, and thus severe dengue fever. High circulating levels of the viral protein NS1, indicative of disease severity, correlated with high concentrations of serum hyaluronan. NS1 exposure decreased the expression of CD44 in differentiating endothelial cells impairing the integrity of vessel-like structures, and promoted the synthesis of hyaluronan in dermal fibroblasts and endothelial cells in synergy with dengue-induced pro-inflammatory mediators. Deposited hyaluronan-rich matrices around cells cultured in vitro recruited CD44-expressing macrophage-like cells, suggesting a mechanism for enhancement of inflammation. In cultured endothelial cells, perturbed hyaluronan-CD44 interactions enhanced endothelial permeability through modulation of VE-cadherin and cytoskeleton re-organization, and exacerbated the NS1-induced disruption of endothelial integrity.Interpretation: Pharmacological targeting of hyaluronan biosynthesis and/or its CD44-mediated signaling may limit the life-threatening vascular leakiness during moderate-to-severe dengue virus infection.
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| 10. |
- Maturi, Varun, et al.
(författare)
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Genomewide binding of transcription factor Snail1 in triple-negative breast cancer cells
- 2018
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Ingår i: Molecular Oncology. - : WILEY. - 1574-7891 .- 1878-0261. ; 12:7, s. 1153-1174
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Tidskriftsartikel (refereegranskat)abstract
- Transcriptional regulation mediated by the zinc finger protein Snail1 controls early embryogenesis. By binding to the epithelial tumor suppressor CDH1 gene, Snail1 initiates the epithelial-mesenchymal transition (EMT). The EMT generates stem-like cells and promotes invasiveness during cancer progression. Accordingly, Snail1 mRNA and protein is abundantly expressed in triple-negative breast cancers with enhanced metastatic potential and phenotypic signs of the EMT. Such high endogenous Snail1 protein levels permit quantitative chromatin immunoprecipitation-sequencing (ChIP-seq) analysis. Snail1 associated with 185 genes at cis regulatory regions in the Hs578T triple-negative breast cancer cell model. These genes include morphogenetic regulators and signaling components that control polarized differentiation. Using the CRISPR/Cas9 system in Hs578T cells, a double deletion of 10bp each was engineered into the first exon and into the second exon-intron junction of Snail1, suppressing Snail1 expression and causing misregulation of several hundred genes. Specific attention to regulators of chromatin organization provides a possible link to new phenotypes uncovered by the Snail1 loss-of-function mutation. On the other hand, genetic inactivation of Snail1 was not sufficient to establish a full epithelial transition to these tumor cells. Thus, Snail1 contributes to the malignant phenotype of breast cancer cells via diverse new mechanisms.
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