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1.
Dalton Trans ; 53(21): 9042-9051, 2024 May 28.
Article in English | MEDLINE | ID: mdl-38727523

ABSTRACT

The reaction between neutral bis(picolinate)copper(II) complexes and copper(II)-monosubstituted Keggin-type phosphotungstate anions formed in situ leads to the formation of the hybrid [C(NH2)3]10[{PW11O39Cu(H2O)}2{Cu(pic)2}]·10H2O compound (1, pic = picolinate) in the presence of structure-directing guanidinium cations. Single-crystal X-ray diffraction studies demonstrate that 1 contains dimeric {PW11O39Cu(H2O)}2{Cu(pic)2} molecular species constituted by two Keggin-type anions linked by one {Cu(pic)2} octahedral complex through axial coordination to their terminal oxygen atoms. The extensive hydrogen-bonding network established by guanidium cations and Keggin clusters plays a key role in retaining the crystallinity of the system throughout dehydration to allow a single-crystal-to-single-crystal (SCSC) transformation into the anhydrous [C(NH2)3]10[{PW11O39Cu}2{Cu(pic)2}] (2a) at 170 °C. Structural modifications involve the re-orientation, shifting in ca. 1.5 Å and condensation of all the {PW11O39Cu} units to result in {PW11O39Cu}n chains in an unprecedented solid-state polymerisation. This phase transition also implies the cleavage of Cu-O bonds induced by the rotation and translation of Keggin-type anions, in such a way that hybrid dimeric units in 1 are dismantled and {Cu(pic)2} complexes become square planar. The irreversibility of the phase transition has been confirmed by combined thermal and diffractometric analyses, which evidence that the anhydrous phase adsorbs only one water molecule per cluster to become the [C(NH2)3]10[{PW11O39Cu}2{Cu(pic)2}]·2H2O (2h) hydrated derivative without any significant alteration in its cell parameters, nor in its crystalline structure. Phase transformations have been monitored by electron paramagnetic resonance spectroscopy.

2.
Glycobiology ; 34(3)2024 Apr 01.
Article in English | MEDLINE | ID: mdl-38227775

ABSTRACT

CD14 is an innate immune receptor that senses pathogen-associated molecular patterns, such as lipopolysaccharide, to activate the innate immune response. Although CD14 is known to be glycosylated, detailed understanding about the structural and functional significance of this modification is still missing. Herein, an NMR and MS-based study, assisted by MD simulations, has provided a 3D-structural model of glycosylated CD14. Our results reveal the existence of a key N-glycosylation site at Asn282 that exclusively contains unprocessed oligomannnose N-glycans that perfectly fit the concave cavity of the bent-solenoid shaped protein. This site is not accessible to glycosidases and is fundamental for protein folding and secretion. A second N-site at Asn151 displays mostly complex N-glycans, with the typical terminal epitopes of the host cell-line expression system (i.e. ßGal, α2,3 and α2,6 sialylated ßGal, here), but also particularities, such as the lack of core fucosylation. The glycan at this site points outside the protein surface, resulting in N-glycoforms fully exposed and available for interactions with lectins. In fact, NMR experiments show that galectin-4, proposed as a binder of CD14 on monocytes to induce their differentiation into macrophages-like cells, interacts in vitro with CD14 through the recognition of the terminal glycoepitopes on Asn151. This work provides key information about CD14 glycosylation, which helps to better understand its functional roles and significance. Although protein glycosylation is known to be dynamic and influenced by many factors, some of the features found herein (presence of unprocessed N-glycans and lack of core Fuc) are likely to be protein specific.


Subject(s)
Lectins , Polysaccharides , Glycosylation , Polysaccharides/chemistry , Lectins/metabolism , Cell Line , Lipopolysaccharides/metabolism
3.
Lab Invest ; 104(1): 100286, 2024 01.
Article in English | MEDLINE | ID: mdl-37951307

ABSTRACT

A significant number of breast cancers develop resistance to hormone therapy. This progression, while posing a major clinical challenge, is difficult to predict. Despite important contributions made by cell models and clinical studies to tackle this problem, both present limitations when taken individually. Experiments with cell models are highly reproducible but do not reflect the indubitable heterogenous landscape of breast cancer. On the other hand, clinical studies account for this complexity but introduce uncontrolled noise due to external factors. Here, we propose a new approach for biomarker discovery that is based on a combined analysis of sequencing data from controlled MCF7 cell experiments and heterogenous clinical samples that include clinical and sequencing information from The Cancer Genome Atlas. Using data from differential gene expression analysis and a Bayesian logistic regression model coupled with an original simulated annealing-type algorithm, we discovered a novel 6-gene signature for stratifying patient response to hormone therapy. The experimental observations and computational analysis built on independent cohorts indicated the superior predictive performance of this gene set over previously known signatures of similar scope. Together, these findings revealed a new gene signature to identify patients with breast cancer with an increased risk of developing resistance to endocrine therapy.


Subject(s)
Breast Neoplasms , Gene Expression Profiling , Humans , Female , Bayes Theorem , Breast Neoplasms/drug therapy , Breast Neoplasms/genetics , Hormones/therapeutic use , Prognosis
4.
Int J Mol Sci ; 24(15)2023 Jul 30.
Article in English | MEDLINE | ID: mdl-37569585

ABSTRACT

In healthy tissues, cells are in mechanical homeostasis. During cancer progression, this equilibrium is disrupted. Cancer cells alter their mechanical phenotype to a softer and more fluid-like one than that of healthy cells. This is connected to cytoskeletal remodeling, changed adhesion properties, faster cell proliferation and increased cell motility. In this work, we investigated the mechanical properties of breast cancer cells representative of different breast cancer subtypes, using MCF-7, tamoxifen-resistant MCF-7, MCF10A and MDA-MB-231 cells. We derived viscoelastic properties from atomic force microscopy force spectroscopy measurements and showed that the mechanical properties of the cells are associated with cancer cell malignancy. MCF10A are the stiffest and least fluid-like cells, while tamoxifen-resistant MCF-7 cells are the softest ones. MCF-7 and MDA-MB-231 show an intermediate mechanical phenotype. Confocal fluorescence microscopy on cytoskeletal elements shows differences in actin network organization, as well as changes in focal adhesion localization. These findings provide further evidence of distinct changes in the mechanical properties of cancer cells compared to healthy cells and add to the present understanding of the complex alterations involved in tumorigenesis.


Subject(s)
Breast Neoplasms , Cytoskeleton , Humans , Female , Cell Line, Tumor , Cytoskeleton/metabolism , MCF-7 Cells , Actins/metabolism , Tamoxifen/pharmacology , Tamoxifen/metabolism , Breast Neoplasms/metabolism , Microscopy, Atomic Force/methods
5.
J Mammary Gland Biol Neoplasia ; 28(1): 17, 2023 07 14.
Article in English | MEDLINE | ID: mdl-37450065

ABSTRACT

On 8 December 2022 the organizing committee of the European Network for Breast Development and Cancer labs (ENBDC) held its fifth annual Think Tank meeting in Amsterdam, the Netherlands. Here, we embraced the opportunity to look back to identify the most prominent breakthroughs of the past ten years and to reflect on the main challenges that lie ahead for our field in the years to come. The outcomes of these discussions are presented in this position paper, in the hope that it will serve as a summary of the current state of affairs in mammary gland biology and breast cancer research for early career researchers and other newcomers in the field, and as inspiration for scientists and clinicians to move the field forward.


Subject(s)
Breast Neoplasms , Mammary Glands, Human , Humans , Female , Breast , Biology
6.
Microsc Res Tech ; 86(9): 1069-1078, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37345422

ABSTRACT

Cells generate traction forces to probe the mechanical properties of the surroundings and maintain a basal equilibrium state of stress. Traction forces are also implicated in cell migration, adhesion and ECM remodeling, and alteration of these forces is often observed in pathologies such as cancer. Thus, analyzing the traction forces is important for studies of cell mechanics in cancer and metastasis. In this primer, the methodology for conducting two-dimensional traction force microscopy (2D-TFM) experiments is reported. As a practical example, we analyzed the traction forces generated by three human breast cancer cell lines of different metastatic potential: MCF10-A, MCF-7 and MDA-MB-231 cells, and studied the effects of actin cytoskeleton disruption on those traction forces. Contrary to what is often reported in literature, lower traction forces were observed in cells with higher metastatic potential (MDA-MB-231). Implications of substrate stiffness and concentration of extracellular matrix proteins in such findings are discussed in the text. RESEARCH HIGHLIGHTS: Traction force microscopy (TFM) is suitable for studying and quantifying cell-substrate and cell-cell forces. TFM is suitable for investigating the relationship between chemical to mechanical signal transduction and vice versa. TFM can be combined with classical indentation studies providing a compact picture of cell mechanics. TFM still needs new physico-chemical (sample preparation) and computational approaches for more accurate data evaluation.


Subject(s)
Mechanical Phenomena , Traction , Humans , Microscopy, Atomic Force/methods , Cell Adhesion/physiology , Cell Movement/physiology
7.
Sci Rep ; 13(1): 3087, 2023 02 22.
Article in English | MEDLINE | ID: mdl-36813800

ABSTRACT

Cell mechanical properties have been proposed as label free markers for diagnostic purposes in diseases such as cancer. Cancer cells show altered mechanical phenotypes compared to their healthy counterparts. Atomic Force Microscopy (AFM) is a widely utilized tool to study cell mechanics. These measurements often need skilful users, physical modelling of mechanical properties and expertise in data interpretation. Together with the need to perform many measurements for statistical significance and to probe wide enough areas in tissue structures, the application of machine learning and artificial neural network techniques to automatically classify AFM datasets has received interest recently. We propose the use of self-organizing maps (SOMs) as unsupervised artificial neural network applied to mechanical measurements performed via AFM on epithelial breast cancer cells treated with different substances that affect estrogen receptor signalling. We show changes in mechanical properties due to treatments, as estrogen softened the cells, while resveratrol led to an increase in cell stiffness and viscosity. These data were then used as input for SOMs. Our approach was able to distinguish between estrogen treated, control and resveratrol treated cells in an unsupervised manner. In addition, the maps enabled investigation of the relationship of the input variables.


Subject(s)
Algorithms , Neoplasms , Microscopy, Atomic Force/methods , Resveratrol , Viscosity , Neural Networks, Computer
8.
J Mech Behav Biomed Mater ; 125: 104979, 2022 01.
Article in English | MEDLINE | ID: mdl-34826769

ABSTRACT

Cells sense stiffness of surrounding tissues and adapt their activity, proliferation, motility and mechanical properties based on such interactions. Cells probe the stiffness of the substrate by anchoring and pulling to their surroundings, transmitting force to the extracellular matrix and other cells, and respond to the resistance they sense, mainly through changes in their cytoskeleton. Cancer and other diseases alter stiffness of tissues, and the response of cancer cells to this stiffness can also be affected. In the present study we show that MCF-7 breast cancer cells seeded on polyacrylamide gels have the ability to detect the stiffness of the substrate and alter their mechanical properties in response. MCF-7 cells plated on soft substrates display lower stiffness and viscosity when compared to those seeded on stiffer gels or glass. These differences can be associated with differences in the morphology and cytoskeleton organisation, since cells seeded on soft substrates have a round morphology, while cells seeded on stiffer substrates acquire a flat and spread morphology with formation of actin filaments, similar to that observed when seeded on glass. These findings show that MCF-7 cells can detect the stiffness of the surrounding microenvironment and thus, modify their mechanical properties.


Subject(s)
MCF-7 Cells , Humans
9.
Inorg Chem ; 60(19): 14913-14923, 2021 Oct 04.
Article in English | MEDLINE | ID: mdl-34546040

ABSTRACT

The hybrid compound [Cu(cyclam)(H2O)2]0.5[{Cu(cyclam)}1.5{B-H2As2Mo6O26(H2O)}]·9H2O (1) (cyclam = 1,4,8,11-tetraazacyclotetradecane) was synthesized in aqueous solution by reacting the {Cu(cyclam)}2+ complex with a mixture of heptamolybdate and an arsenate(V) source. Crystal packing of 1 exhibits a supramolecular open-framework built of discrete covalent molybdoarsenate/metalorganic units and additional [Cu(cyclam)(H2O)2]2+ cations, the stacking of which generates squarelike channels parallel to the z axis with an approximate cross section of 10 × 11 Å2 where all the hydration water molecules are hosted. Thermal evacuation of solvent molecules yields a new anhydrous crystalline phase, but compound 1 does not preserve its single-crystalline nature upon heating. However, when crystals are dehydrated under vacuum, they undergo a structural transformation that proceeds via a single-crystal-to-single-crystal pathway, leading to the anhydrous phase [{Cu(cyclam)}2(A-H2As2Mo6O26)] (2). Total dehydration results in important modifications within the inorganic cluster skeleton which reveals an unprecedented solid-state B to A isomerization of the polyoxoanion. This transition also involves changes in the CuII bonding scheme that lead to covalent cluster/metalorganic layers by retaining the open-framework nature of 1. Compound 2 adsorbs ambient moisture upon air exposure, but it does not revert back to 1, and the hydrated phase [{Cu(cyclam)}2(A-H2As2Mo6O26)]·6H2O (2h) is obtained instead. Structural variations between 1 and 2 are reflected in electron paramagnetic resonance spectroscopy measurements, and the permanent microporosity of 2 provides interesting functionalities to the system such as the selective adsorption of gaseous CO2 over N2.

10.
Semin Cancer Biol ; 73: 58-75, 2021 08.
Article in English | MEDLINE | ID: mdl-33309851

ABSTRACT

Nuclear receptors (NRs) are a superfamily of ligand-activated transcription factors that act as biological sensors and use a combination of mechanisms to modulate positively and negatively gene expression in a spatial and temporal manner. The highly orchestrated biological actions of several NRs influence the proliferation, differentiation, and apoptosis of many different cell types. Synthetic ligands for several NRs have been the focus of extensive drug discovery efforts for cancer intervention. This review summarizes the roles in tumour growth and metastasis of several relevant NR family members, namely androgen receptor (AR), estrogen receptor (ER), glucocorticoid receptor (GR), thyroid hormone receptor (TR), retinoic acid receptors (RARs), retinoid X receptors (RXRs), peroxisome proliferator-activated receptors (PPARs), and liver X receptors (LXRs). These studies are key to develop improved therapeutic agents based on novel modes of action with reduced side effects and overcoming resistance.


Subject(s)
Hormones , Lipids , Neoplasms , Receptors, Cytoplasmic and Nuclear , Animals , Humans
11.
Elife ; 92020 09 10.
Article in English | MEDLINE | ID: mdl-32909943

ABSTRACT

SOX11 is an embryonic mammary epithelial marker that is normally silenced prior to birth. High SOX11 levels in breast tumours are significantly associated with distant metastasis and poor outcome in breast cancer patients. Here, we show that SOX11 confers distinct features to ER-negative DCIS.com breast cancer cells, leading to populations enriched with highly plastic hybrid epithelial/mesenchymal cells, which display invasive features and alterations in metastatic tropism when xenografted into mice. We found that SOX11+DCIS tumour cells metastasize to brain and bone at greater frequency and to lungs at lower frequency compared to cells with lower SOX11 levels. High levels of SOX11 leads to the expression of markers associated with mesenchymal state and embryonic cellular phenotypes. Our results suggest that SOX11 may be a potential biomarker for breast tumours with elevated risk of developing metastases and may require more aggressive therapies.


Subject(s)
Breast Neoplasms , Epithelial-Mesenchymal Transition/genetics , Neoplasm Invasiveness/pathology , SOXC Transcription Factors/metabolism , Animals , Biomarkers, Tumor/metabolism , Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Carcinoma, Intraductal, Noninfiltrating/metabolism , Carcinoma, Intraductal, Noninfiltrating/pathology , Cell Line, Tumor , Cell Proliferation/drug effects , Female , Heterografts , Humans , Mice , SOXC Transcription Factors/genetics , SOXC Transcription Factors/pharmacology
12.
Cells ; 9(4)2020 04 10.
Article in English | MEDLINE | ID: mdl-32290242

ABSTRACT

The replacement of the cantilever tip by a living cell in Atomic Force Microscopy (AFM) experiments permits the direct quantification of cell-substrate and cell-cell adhesion forces. This single-cell probe force measurement technique, when complemented by microscopy, allows controlled manipulation of the cell with defined location at the area of interest. In this work, a setup based on two glass half-slides, a non-fouling one with bacterial S-layer protein SbpA from L. sphaericus CMM 2177 and the second with a fibronectin layer, has been employed to measure the adhesion of MCF7 breast cancer cells to fibronectin films (using SbpA as control) and to other cells (symmetric vs. asymmetric systems). The measurements aimed to characterize and compare the adhesion capacities of parental cells and cells overexpressing the embryonic transcription factor Sox2, which have a higher capacity for invasion and are more resistant to endocrine therapy in vivo. Together with the use of fluorescence techniques (epifluorescence, Total Internal Fluorescence Microscopy (TIRF)), the visualization of vinculin and actin distribution in cells in contact with fibronectin surfaces is enabled, facilitating the monitoring and quantification of the formation of adhesion complexes. These findings demonstrate the strength of this combined approach to assess and compare the adhesion properties of cell lines and to illustrate the heterogeneity of adhesive strength found in breast cancer cells.


Subject(s)
Breast Neoplasms/genetics , Cell Adhesion/physiology , Microscopy, Atomic Force/methods , SOXB1 Transcription Factors/metabolism , Breast Neoplasms/pathology , Female , Humans , MCF-7 Cells
13.
Clin Cancer Res ; 26(13): 3420-3430, 2020 07 01.
Article in English | MEDLINE | ID: mdl-32161121

ABSTRACT

PURPOSE: The tumor microenvironment plays a key role in cancer development and progression and is involved in resistance to chemo- and immunotherapy. Cancer-associated fibroblast expressing fibroblast-activating protein α (FAPα) is one of the predominant stroma cell types and is involved in resistance to immunotherapy. EXPERIMENTAL DESIGN: We generated OMTX705, a novel antibody-drug conjugate from a humanized anti-FAP antibody linked to a new cytolysin. Here, we studied its antineoplastic activity in vitro and in preclinical mouse models alone and in combination with chemotherapy as well as immunotherapy in PD-1-resistant tumors. RESULTS: In Avatar models, OMTX705 showed a 100% tumor growth inhibition and prolonged tumor regressions as single agent and in combination with chemotherapy. Treatment rechallenge following treatment discontinuation induced additional tumor regression, suggesting lack of treatment resistance. In a mouse model with a humanized immune system resistant to PD-1 inhibition, OMTX705 increased tumor infiltration by CD8+ T cells, induced complete regressions, and delayed tumor recurrence. CONCLUSIONS: These data suggest that FAP targeting with OMTX705 represents a novel and potent strategy for cancer treatment, including tumors resistant to immunotherapy, and support its clinical development.


Subject(s)
Antineoplastic Agents/pharmacology , Drug Resistance, Neoplasm/drug effects , Immunoconjugates/pharmacology , Membrane Proteins/antagonists & inhibitors , Animals , Antibodies, Monoclonal, Humanized/pharmacology , Cell Line, Tumor , Cell Survival/drug effects , Disease Models, Animal , Dose-Response Relationship, Drug , Endopeptidases , Humans , Immunomodulation/drug effects , Mice , Tumor Microenvironment/drug effects , Tumor Microenvironment/immunology , Xenograft Model Antitumor Assays
14.
Int J Mol Sci ; 20(13)2019 Jul 03.
Article in English | MEDLINE | ID: mdl-31277289

ABSTRACT

Atomic force microscopy (AFM) combined with fluorescence microscopy has been used to quantify cytomechanical modifications induced by resveratrol (at a fixed concentration of 50 µM) in a breast cancer cell line (MCF-7) upon temporal variation. Cell indentation methodology has been utilized to determine simultaneous variations of Young's modulus, the maximum adhesion force, and tether formation, thereby determining cell motility and adhesiveness. Effects of treatment were measured at several time-points (0-6 h, 24 h, and 48 h); longer exposures resulted in cell death. Our results demonstrated that AFM can be efficiently used as a diagnostic tool to monitor irreversible morpho/nano-mechanical changes in cancer cells during the early steps of drug treatment.


Subject(s)
Breast Neoplasms/physiopathology , Cell Adhesion/drug effects , Cell Movement/drug effects , Elastic Modulus/drug effects , Microscopy, Atomic Force/methods , Resveratrol/pharmacology , Breast Neoplasms/diagnosis , Breast Neoplasms/drug therapy , Female , Humans , MCF-7 Cells , Mechanical Phenomena/drug effects , Resveratrol/therapeutic use
15.
Cancers (Basel) ; 11(7)2019 Jun 28.
Article in English | MEDLINE | ID: mdl-31261741

ABSTRACT

The expression of the secreted factor Wnt-11 is elevated in several types of cancer, including colorectal cancer, where it promotes cancer cell migration and invasion. Analysis of colorectal cancer gene expression databases associated WNT11 mRNA expression with increased likelihood of metastasis in a subset of patients. WNT11 expression was correlated with the expression of the Wnt receptors FZD6, RYK, and PTK7, and the combined expression of WNT11, FZD6 and RYK or PTK7 was associated with an increased risk of 5-year mortality rates. Immunohistochemical analysis of Wnt-11 in a cohort of 357 colorectal cancer patients found significantly higher Wnt-11 levels in tumors, compared with benign tissue. Elevated Wnt-11 levels occurred more frequently in rectal tumors than in colonic tumors and in tumors from women than men. In univariate analysis, increased Wnt-11 expression was also associated with tumor invasion and increased 5-year mortality. High Wnt-11 levels were not associated with high levels of nuclear ß-catenin, suggesting Wnt-11 is not simply an indicator for activation of ß-catenin-dependent signaling. Expression of Wnt-11 in colorectal cancer cell lines expressing low endogenous Wnt-11 inhibited ß-catenin/Tcf activity and increased ATF2-dependent transcriptional activity. WNT11 gene silencing and antibody-mediated inhibition of Wnt-11 in colorectal cancer cell lines expressing high Wnt-11 reduced their capacity for invasion. Together, these observations suggest that Wnt-11 could be a potential target for the treatment of patients with invasive colorectal cancer.

16.
Carbohydr Polym ; 213: 159-167, 2019 Jun 01.
Article in English | MEDLINE | ID: mdl-30879655

ABSTRACT

Polyoxometalates (POMs) have been revealed as interesting antitumor agents inhibiting the action of Sox2 transcription factor, which reduces the risk of metastasis during hormonal therapies. However, they have shown serious concerns to be incorporated into the cells due to their cytotoxicity. Taking this into consideration, this study aims to develop polyoxometalate-based nanocarriers to be potentially applied as new forms of anticancer therapies. Thus, the Wells-Dawson type [P2Mo18O62]6- phosphomolybdate was physically loaded into covalently crosslinked chitosan nanogels that can act as nanocarriers for local delivery. The obtained nanocomposites were extensively characterized by 31P-NMR, TEM microscopy, DLS and zeta potential measurements. This work revealed that selected chitosan nanocarriers would present great potential for POM delivery into tumoral cells due to their pH-triggered deliverability that inhibits cytotoxic drug release at physiological pH. Furthermore, the high uptakes values reported herein make prepared nanocomposites interesting candidates for future breast antitumoral treatments.


Subject(s)
Antineoplastic Agents/therapeutic use , Breast Neoplasms/drug therapy , Chitosan/chemistry , Polyethylene Glycols/chemistry , Polyethyleneimine/chemistry , Tungsten Compounds/therapeutic use , Antineoplastic Agents/chemistry , Chitosan/chemical synthesis , Drug Carriers/chemical synthesis , Drug Carriers/chemistry , Female , Humans , Hydrogen-Ion Concentration , Nanogels , Particle Size , Polyethylene Glycols/chemical synthesis , Polyethyleneimine/chemical synthesis , Surface Properties , Tungsten Compounds/chemistry
17.
Oncogene ; 38(17): 3151-3169, 2019 04.
Article in English | MEDLINE | ID: mdl-30622340

ABSTRACT

Increased cancer stem cell content during development of resistance to tamoxifen in breast cancer is driven by multiple signals, including Sox2-dependent activation of Wnt signalling. Here, we show that Sox2 increases and estrogen reduces the expression of the transcription factor Sox9. Gain and loss of function assays indicate that Sox9 is implicated in the maintenance of human breast luminal progenitor cells. CRISPR/Cas knockout of Sox9 reduces growth of tamoxifen-resistant breast tumours in vivo. Mechanistically, Sox9 acts downstream of Sox2 to control luminal progenitor cell content and is required for expression of the cancer stem cell marker ALDH1A3 and Wnt signalling activity. Sox9 is elevated in breast cancer patients after endocrine therapy failure. This new regulatory axis highlights the relevance of SOX family transcription factors as potential therapeutic targets in breast cancer.


Subject(s)
Breast Neoplasms/metabolism , Breast/metabolism , Drug Resistance, Neoplasm , Neoplastic Stem Cells/metabolism , SOX9 Transcription Factor/metabolism , SOXB1 Transcription Factors/metabolism , Breast/cytology , Breast Neoplasms/drug therapy , Breast Neoplasms/genetics , Cell Line , Cell Proliferation , Epithelial Cells/cytology , Estrogens/pharmacology , Female , Gene Expression Regulation, Neoplastic , Humans , MCF-7 Cells , SOX9 Transcription Factor/genetics , Signal Transduction , Tamoxifen/pharmacology , Up-Regulation
18.
Oncogene ; 37(39): 5305-5324, 2018 09.
Article in English | MEDLINE | ID: mdl-29858602

ABSTRACT

Aberrant transforming growth factor-ß (TGF-ß) signaling is a hallmark of the stromal microenvironment in cancer. Dickkopf-3 (Dkk-3), shown to inhibit TGF-ß signaling, is downregulated in prostate cancer and upregulated in the stroma in benign prostatic hyperplasia, but the function of stromal Dkk-3 is unclear. Here we show that DKK3 silencing in WPMY-1 prostate stromal cells increases TGF-ß signaling activity and that stromal cell-conditioned media inhibit prostate cancer cell invasion in a Dkk-3-dependent manner. DKK3 silencing increased the level of the cell-adhesion regulator TGF-ß-induced protein (TGFBI) in stromal and epithelial cell-conditioned media, and recombinant TGFBI increased prostate cancer cell invasion. Reduced expression of Dkk-3 in patient tumors was associated with increased expression of TGFBI. DKK3 silencing reduced the level of extracellular matrix protein-1 (ECM-1) in prostate stromal cell-conditioned media but increased it in epithelial cell-conditioned media, and recombinant ECM-1 inhibited TGFBI-induced prostate cancer cell invasion. Increased ECM1 and DKK3 mRNA expression in prostate tumors was associated with increased relapse-free survival. These observations are consistent with a model in which the loss of Dkk-3 in prostate cancer leads to increased secretion of TGFBI and ECM-1, which have tumor-promoting and tumor-protective roles, respectively. Determining how the balance between the opposing roles of extracellular factors influences prostate carcinogenesis will be key to developing therapies that target the tumor microenvironment.


Subject(s)
Extracellular Matrix Proteins/metabolism , Intercellular Signaling Peptides and Proteins/metabolism , Prostatic Neoplasms/pathology , Transforming Growth Factor beta1/metabolism , Tumor Microenvironment/physiology , Adaptor Proteins, Signal Transducing , Chemokines , Humans , Male , Prostatic Neoplasms/metabolism
19.
Clin Cancer Res ; 24(10): 2452-2463, 2018 05 15.
Article in English | MEDLINE | ID: mdl-29363524

ABSTRACT

Purpose: One third of ER-positive breast cancer patients who initially respond to endocrine therapy become resistant to treatment. Such treatment failure is associated with poor prognosis and remains an area of unmet clinical need. Here, we identify a specific posttranslational modification that occurs during endocrine resistance and which results in tumor susceptibility to the apoptosis-inducer TRAIL. This potentially offers a novel stratified approach to targeting endocrine-resistant breast cancer.Experimental Design: Cell line and primary-derived xenograft models of endocrine resistance were investigated for susceptibility to TRAIL. Tumor viability, cancer stem cell (CSC) viability (tumorspheres), tumor growth kinetics, and metastatic burden were assessed. Western blots for the TRAIL-pathway inhibitor, c-FLIP, and upstream regulators were performed. Results were confirmed in primary culture of 26 endocrine-resistant and endocrine-naïve breast tumors.Results: Breast cancer cell lines with acquired resistance to tamoxifen (TAMR) or faslodex were more sensitive to TRAIL than their endocrine-sensitive controls. Moreover, TRAIL eliminated CSC-like activity in TAMR cells, resulting in prolonged remission of xenografts in vivo In primary culture, TRAIL significantly depleted CSCs in 85% endocrine-resistant, compared with 8% endocrine-naïve, tumors, whereas systemic administration of TRAIL in endocrine-resistant patient-derived xenografts reduced tumor growth, CSC-like activity, and metastases. Acquired TRAIL sensitivity correlated with a reduction in intracellular levels of c-FLIP, and an increase in Jnk-mediated phosphorylation of E3-ligase, ITCH, which degrades c-FLIP.Conclusions: These results identify a novel mechanism of acquired vulnerability to an extrinsic cell death stimulus, in endocrine-resistant breast cancers, which has both therapeutic and prognostic potential. Clin Cancer Res; 24(10); 2452-63. ©2018 AACR.


Subject(s)
Breast Neoplasms/metabolism , CASP8 and FADD-Like Apoptosis Regulating Protein/metabolism , Drug Resistance, Neoplasm , Protein Processing, Post-Translational , Receptors, Estrogen/metabolism , TNF-Related Apoptosis-Inducing Ligand/metabolism , Animals , Antineoplastic Agents, Hormonal/pharmacology , Apoptosis/drug effects , Breast Neoplasms/drug therapy , Breast Neoplasms/genetics , CASP8 and FADD-Like Apoptosis Regulating Protein/genetics , Cell Line, Tumor , Disease Models, Animal , Drug Resistance, Neoplasm/genetics , Female , Gene Expression Regulation, Neoplastic/drug effects , Humans , Mice , Neoplastic Stem Cells/drug effects , Neoplastic Stem Cells/metabolism , TNF-Related Apoptosis-Inducing Ligand/pharmacology , Xenograft Model Antitumor Assays
20.
Polymers (Basel) ; 10(12)2018 Dec 03.
Article in English | MEDLINE | ID: mdl-30961262

ABSTRACT

New strategies in regenerative medicine include the implantation of stem cells cultured in bio-resorbable polymeric scaffolds to restore the tissue function and be absorbed by the body after wound healing. This requires the development of appropriate micro-technologies for manufacturing of functional scaffolds with controlled surface properties to induce a specific cell behavior. The present report focuses on the effect of substrate topography on the behavior of human mesenchymal stem cells (MSCs) before and after co-differentiation into adipocytes and osteoblasts. Picosecond laser micromachining technology (PLM) was applied on poly (L-lactide) (PLLA), to generate different microstructures (microgrooves and microcavities) for investigating cell shape, orientation, and MSCs co-differentiation. Under certain surface topographical conditions, MSCs modify their shape to anchor at specific groove locations. Upon MSCs differentiation, adipocytes respond to changes in substrate height and depth by adapting the intracellular distribution of their lipid vacuoles to the imposed physical constraints. In addition, topography alone seems to produce a modest, but significant, increase of stem cell differentiation to osteoblasts. These findings show that PLM can be applied as a high-efficient technology to directly and precisely manufacture 3D microstructures that guide cell shape, control adipocyte morphology, and induce osteogenesis without the need of specific biochemical functionalization.

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