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1.
Gastric Cancer ; 26(2): 234-249, 2023 03.
Article in English | MEDLINE | ID: mdl-36528833

ABSTRACT

BACKGROUND: Cancer stem cells (CSCs) are at the origin of tumour initiation and progression in gastric adenocarcinoma (GC). However, markers of metastasis-initiating cells remain unidentified in GC. In this study, we characterized CD44 variants expressed in GC and evaluated the tumorigenic and metastatic properties of CD44v3+ cells and their clinical significance in GC patients. METHODS: Using GC cell lines and patient-derived xenografts, we evaluated CD44+ and CD44v3+ GC cells molecular signature and their tumorigenic, chemoresistance, invasive and metastatic properties, and expression in patients-derived tissues. RESULTS: CD44v3+ cells, which represented a subpopulation of CD44+ cells, were detected in advanced preneoplastic lesions and presented CSCs chemoresistance and tumorigenic properties in vitro and in vivo. Molecular and functional analyses revealed two subpopulations of gastric CSCs: CD44v3+ CSCs with an epithelial-mesenchymal transition (EMT)-like signature, and CD44+/v3- CSCs with an epithelial-like signature; both were tumorigenic but CD44v3+ cells showed higher invasive and metastatic properties in vivo. CD44v3+ cells detected in the primary tumours of GC patients were associated with a worse prognosis. CONCLUSION: CD44v3 is a marker of a subpopulation of CSCs with metastatic properties in GC. The identification of metastasis-initiating cells in GC represents a major advance for further development of anti-metastatic therapeutic strategies.


Subject(s)
Carcinoma , Stomach Neoplasms , Humans , Stomach Neoplasms/pathology , Neoplastic Stem Cells/metabolism , Carcinoma/pathology , Hyaluronan Receptors , Epithelial-Mesenchymal Transition
2.
Int J Cancer ; 146(8): 2255-2267, 2020 04 15.
Article in English | MEDLINE | ID: mdl-31489619

ABSTRACT

Gastric carcinomas (GC) are heterogeneous tumors, composed of a subpopulation of cluster of differentiation-44 (CD44)+ tumorigenic and chemoresistant cancer stem cells (CSC). YAP1 and TAZ oncoproteins (Y/T) interact with TEA domain family member 1 (TEAD) transcription factors to promote cell survival and proliferation in multiple tissues. Their activity and role in GC remain unclear. This work aimed to analyze Y/T-TEAD activity and molecular signature in gastric CSC, and to assess the effect of verteporfin, a Food and Drug Administration-approved drug preventing Y/T-TEAD interaction, on gastric CSC tumorigenic properties. Y/T-TEAD molecular signature was investigated using bioinformatical (KmPlot database), transcriptomic and immunostaining analyses in patient-derived GC and cell lines. Verteporfin effects on Y/T-TEAD transcriptional activity, CSC proliferation and tumorigenic properties were evaluated using in vitro tumorsphere assays and mouse models of patient-derived GC xenografts. High expressions of YAP1, TAZ, TEAD1, TEAD4 and their target genes were associated with low overall survival in nonmetastatic human GC patients (n = 444). This Y/T-TEAD molecular signature was enriched in CD44+ patient-derived GC cells and in cells resistant to conventional chemotherapy. Verteporfin treatment inhibited Y/T-TEAD transcriptional activity, cell proliferation and CD44 expression, and decreased the pool of tumorsphere-forming CD44+ /aldehyde dehydrogenase (ALDH)high gastric CSC. Finally, verteporfin treatment inhibited GC tumor growth in vivo; the residual tumor cells exhibited reduced expressions of CD44 and ALDH1, and more importantly, they were unable to initiate new tumorspheres in vitro. All these data demonstrate that Y/T-TEAD activity controls gastric CSC tumorigenic properties. The repositioning of verteporfin targeting YAP1/TAZ-TEAD activity could be a promising CSC-based strategy for the treatment of GC.


Subject(s)
Adaptor Proteins, Signal Transducing/genetics , DNA-Binding Proteins/genetics , Neoplastic Stem Cells/drug effects , Nuclear Proteins/genetics , Stomach Neoplasms/drug therapy , Stomach Neoplasms/genetics , Trans-Activators/genetics , Transcription Factors/genetics , Verteporfin/pharmacology , Adaptor Proteins, Signal Transducing/metabolism , Animals , Cell Growth Processes/drug effects , Cell Line, Tumor , DNA-Binding Proteins/metabolism , Drug Resistance, Neoplasm , Humans , Hyaluronan Receptors/biosynthesis , Hyaluronan Receptors/genetics , Male , Mice , Mice, Inbred NOD , Mice, SCID , Molecular Targeted Therapy , Neoplastic Stem Cells/metabolism , Neoplastic Stem Cells/pathology , Nuclear Proteins/metabolism , Stomach Neoplasms/metabolism , Stomach Neoplasms/pathology , TEA Domain Transcription Factors , Trans-Activators/metabolism , Transcription Factors/metabolism , Transcription, Genetic/drug effects , Transcriptional Coactivator with PDZ-Binding Motif Proteins , Up-Regulation , Xenograft Model Antitumor Assays , YAP-Signaling Proteins
3.
Int J Mol Sci ; 19(11)2018 Oct 29.
Article in English | MEDLINE | ID: mdl-30380687

ABSTRACT

Gastric cancer (GC) is the third leading cause of cancer-related death worldwide with a five-year survival rate of around 25%, and 4% when diagnosed at a metastatic stage. Cancer stem cells (CSC) have recently been characterized as being responsible for resistance to radio/chemotherapies and metastasis formation, opening up perspectives for new targeted therapies. Those CSCs express biomarkers such as cluster of differentiation 44 (CD44) and display high aldehyde dehydrogenase activity that converts vitamin A-derived retinal into retinoic acids. All-trans retinoic acid (ATRA), which has pro-differentiating properties, has revolutionized the prognosis of acute promyelotic leukemia by increasing its remission rate from 15% to 85%. Recent studies have started to show that ATRA also has an anti-tumoral role on solid cancers such as GC. The purpose of this review is therefore to summarize the work that evaluated the effects of ATRA in GC and to evaluate whether its anti-cancerous action involves gastric CSCs targeting. It has been demonstrated that ATRA can block the cell cycle, enhance apoptosis, and decrease gastric CSCs properties in GC cell lines, tumorspheres, and patient-derived xenograft mice models. Therefore, retinoids and new synthetic retinoids seem to be a promising step forward in targeted therapy of gastric CSC in combination with existing chemotherapies. Future studies should probably focus on these points.


Subject(s)
Antineoplastic Agents/therapeutic use , Stomach Neoplasms/drug therapy , Tretinoin/therapeutic use , Animals , Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Cell Cycle/drug effects , Humans , Hyaluronan Receptors/analysis , Hyaluronan Receptors/metabolism , Neoplastic Stem Cells/drug effects , Neoplastic Stem Cells/metabolism , Neoplastic Stem Cells/pathology , Retinoid X Receptors/analysis , Retinoid X Receptors/metabolism , Stomach/drug effects , Stomach/pathology , Stomach Neoplasms/metabolism , Stomach Neoplasms/pathology , Tretinoin/pharmacology
4.
Soins Gerontol ; 22(127): 34-39, 2017.
Article in French | MEDLINE | ID: mdl-28917335

ABSTRACT

The hospital-community interface represents a real challenge in the care of elderly people. A lack of coordination and communication is the main obstacle to ensuring the fluidity of this pathway. On a definite territory, a new hospital-community liaison sheet was developed as the result of a collaborative approach and then evaluated. This simple, useful and effective cross-professional tool, is the first step towards improving communication between these two universes.


Subject(s)
Community Health Services/organization & administration , Hospitals, Community , Patient Discharge , Patient Transfer/organization & administration , Quality Improvement/organization & administration , Aged , Aged, 80 and over , France , Humans , Interdisciplinary Communication , Intersectoral Collaboration , Nursing Audit
5.
Cell Rep ; 43(2): 113773, 2024 Feb 27.
Article in English | MEDLINE | ID: mdl-38350444

ABSTRACT

Hepatocellular carcinoma (HCC) is an inflammation-associated cancer arising from viral or non-viral etiologies including steatotic liver diseases (SLDs). Expansion of immunosuppressive myeloid cells is a hallmark of inflammation and cancer, but their heterogeneity in HCC is not fully resolved and might underlie immunotherapy resistance. Here, we present a high-resolution atlas of innate immune cells from patients with HCC that unravels an SLD-associated contexture characterized by influx of inflammatory and immunosuppressive myeloid cells, including a discrete population of THBS1+ regulatory myeloid (Mreg) cells expressing monocyte- and neutrophil-affiliated genes. THBS1+ Mreg cells expand in SLD-associated HCC, populate fibrotic lesions, and are associated with poor prognosis. THBS1+ Mreg cells are CD163+ but distinguished from macrophages by high expression of triggering receptor expressed on myeloid cells 1 (TREM1), which contributes to their immunosuppressive activity and promotes HCC tumor growth in vivo. Our data support myeloid subset-targeted immunotherapies to treat HCC.


Subject(s)
Carcinoma, Hepatocellular , Liver Neoplasms , Humans , Triggering Receptor Expressed on Myeloid Cells-1 , Immunosuppression Therapy , Myeloid Cells , Immunosuppressive Agents , Inflammation
6.
Cell Death Discov ; 10(1): 120, 2024 Mar 07.
Article in English | MEDLINE | ID: mdl-38453889

ABSTRACT

Gastric cancer's (GC) bad prognosis is usually associated with metastatic spread. Invasive cancer stem cells (CSC) are considered to be the seed of GC metastasis and not all CSCs are able to initiate metastasis. Targeting these aggressive metastasis-initiating CSC (MIC) is thus vital. Leukaemia inhibitory factor (LIF) is hereby used to target Hippo pathway oncogenic members, found to be induced in GC and associated with CSC features. LIF-treated GC cell lines, patient-derived xenograft (PDX) cells and/or CSC tumourspheres underwent transcriptomics, laser microdissection-associated proteomics, 2D and 3D invasion assays and in vivo xenograft in mice blood circulation. LIFR expression was analysed on tissue microarrays from GC patients and in silico from public databases. LIF-treated cells, especially CSC, presented decreased epithelial to mesenchymal transition (EMT) phenotype and invasion capacity in vitro, and lower metastasis initiation ability in vivo. These effects involved both the Hippo and Jak/Stat pathways. Finally, GC's high LIFR expression was associated with better clinical outcomes in patients. LIF treatment could thus represent a targeted anti-CSC strategy to fight against metastatic GC, and LIFR detection in primary tumours could constitute a potential new prognosis marker in this disease.

8.
Biomedicines ; 11(12)2023 Dec 13.
Article in English | MEDLINE | ID: mdl-38137514

ABSTRACT

Cancer stem cells are a subpopulation of tumor cells characterized by their ability to self-renew, induce tumors upon engraftment in animals and exhibit strong resistance to chemotherapy and radiotherapy. These cells exhibit numerous characteristics in common with embryonic stem cells, expressing some of their markers, typically absent in non-pathological adult differentiated cells. The aim of this study was to investigate the potential of conditioned media from cancer stem cells to modulate the fate of Leukemia Inhibitory Factor (LIF)-dependent murine embryonic stem cells (mESCs) as a way to obtain a direct readout of the secretome of cancer cells. A functional assay, "the StemDif sensor test", was developed with two types of cancer stem cells derived from grade IV glioblastoma (adult and pediatric) or from gastric adenocarcinoma. We show that conditioned media from the selection of adult but not pediatric Glioma-Inducing Cells (GICs) maintain mESCs' pluripotency in correlation with LIF secretion and activation of STAT3 protein. In contrast, conditioned media from gastric adenocarcinoma cells display LIF-independent stemness and differentiation activities on mESC. Our test stands out for its user-friendly procedures, affordability and straightforward output, positioning it as a pioneering tool for in-depth exploration of cancer stem cell secretome characteristics.

9.
Cancers (Basel) ; 13(17)2021 Aug 27.
Article in English | MEDLINE | ID: mdl-34503151

ABSTRACT

Hepatocellular carcinoma (HCC) is a classical inflammation-promoted cancer that occurs in a setting of liver diseases, including nonalcoholic fatty liver disease (NAFLD) or alcoholic liver disease (ALD). These pathologies share key characteristics, notably intestinal dysbiosis, increased intestinal permeability and an imbalance in bile acids, choline, fatty acids and ethanol metabolites. Translocation of microbial- and danger-associated molecular patterns (MAMPs and DAMPs) from the gut to the liver elicits profound chronic inflammation, leading to severe hepatic injury and eventually HCC progression. In this review, we first describe how the gut and the liver communicate and discuss mechanisms by which the intestinal microbiota elicit hepatic inflammation and HCC. We focus on the role of microbial products, e.g., MAMPs, host inflammatory effectors and host-microbiome-derived metabolites in tumor-promoting mechanisms, including cell death and senescence. Last, we explore the potential of harnessing the microbiota to treat liver diseases and HCC.

10.
Front Immunol ; 12: 655697, 2021.
Article in English | MEDLINE | ID: mdl-33815418

ABSTRACT

Hepatocellular carcinoma (HCC) is the most common liver tumor and among the deadliest cancers worldwide. Advanced HCC overall survival is meager and has not improved over the last decade despite approval of several tyrosine kinase inhibitors (TKi) for first and second-line treatments. The recent approval of immune checkpoint inhibitors (ICI) has revolutionized HCC palliative care. Unfortunately, the majority of HCC patients fail to respond to these therapies. Here, we elaborate on the immune landscapes of the normal and cirrhotic livers and of the unique HCC tumor microenvironment. We describe the molecular and immunological classifications of HCC, discuss the role of specific immune cell subsets in this cancer, with a focus on myeloid cells and pathways in anti-tumor immunity, tumor promotion and immune evasion. We also describe the challenges and opportunities of immunotherapies in HCC and discuss new avenues based on harnessing the anti-tumor activity of myeloid, NK and γδ T cells, vaccines, chimeric antigen receptors (CAR)-T or -NK cells, oncolytic viruses, and combination therapies.


Subject(s)
Carcinoma, Hepatocellular/immunology , Carcinoma, Hepatocellular/therapy , Disease Susceptibility , Immunotherapy , Liver Neoplasms/immunology , Liver Neoplasms/therapy , Animals , Biomarkers, Tumor , Carcinoma, Hepatocellular/diagnosis , Combined Modality Therapy , Disease Susceptibility/immunology , Genetic Predisposition to Disease , Humans , Immune System/immunology , Immune System/metabolism , Immunomodulation , Immunotherapy/methods , Liver/immunology , Liver/metabolism , Liver/pathology , Liver Neoplasms/diagnosis , Molecular Diagnostic Techniques , Treatment Outcome , Tumor Microenvironment/genetics , Tumor Microenvironment/immunology
11.
Cell Mol Gastroenterol Hepatol ; 9(2): 257-276, 2020.
Article in English | MEDLINE | ID: mdl-31669263

ABSTRACT

BACKGROUND & AIMS: Gastric carcinoma is related mostly to CagA+-Helicobacter pylori infection, which disrupts the gastric mucosa turnover and elicits an epithelial-mesenchymal transition (EMT) and preneoplastic transdifferentiation. The tumor suppressor Hippo pathway controls stem cell homeostasis; its core, constituted by the large tumor suppressor 2 (LATS2) kinase and its substrate Yes-associated protein 1 (YAP1), was investigated in this context. METHODS: Hippo, EMT, and intestinal metaplasia marker expression were investigated by transcriptomic and immunostaining analyses in human gastric AGS and MKN74 and nongastric immortalized RPE1 and HMLE epithelial cell lines challenged by H pylori, and on gastric tissues of infected patients and mice. LATS2 and YAP1 were silenced using small interfering RNAs. A transcriptional enhanced associated domain (TEAD) reporter assay was used. Cell proliferation and invasion were evaluated. RESULTS: LATS2 and YAP1 appear co-overexpressed in the infected mucosa, especially in gastritis and intestinal metaplasia. H pylori via CagA stimulates LATS2 and YAP1 in a coordinated biphasic pattern, characterized by an early transient YAP1 nuclear accumulation and stimulated YAP1/TEAD transcription, followed by nuclear LATS2 up-regulation leading to YAP1 phosphorylation and targeting for degradation. LATS2 and YAP1 reciprocally positively regulate each other's expression. Loss-of-function experiments showed that LATS2 restricts H pylori-induced EMT marker expression, invasion, and intestinal metaplasia, supporting a role of LATS2 in maintaining the epithelial phenotype of gastric cells and constraining H pylori-induced preneoplastic changes. CONCLUSIONS: H pylori infection engages a number of signaling cascades that alienate mucosa homeostasis, including the Hippo LATS2/YAP1/TEAD pathway. In the host-pathogen conflict, which generates an inflammatory environment and perturbations of the epithelial turnover and differentiation, Hippo signaling appears as a protective pathway, limiting the loss of gastric epithelial cell identity that precedes gastric carcinoma development.


Subject(s)
Epithelial-Mesenchymal Transition/immunology , Gastric Mucosa/pathology , Helicobacter Infections/pathology , Precancerous Conditions/pathology , Protein Serine-Threonine Kinases/metabolism , Tumor Suppressor Proteins/metabolism , Adaptor Proteins, Signal Transducing/metabolism , Adenocarcinoma/genetics , Adenocarcinoma/immunology , Adenocarcinoma/pathology , Aged , Aged, 80 and over , Animals , Cell Cycle Proteins/metabolism , Female , Gastric Mucosa/microbiology , Gene Expression Regulation, Neoplastic/immunology , Helicobacter Infections/genetics , Helicobacter Infections/microbiology , Helicobacter pylori/pathogenicity , Host-Pathogen Interactions/genetics , Humans , Male , Metaplasia/genetics , Metaplasia/microbiology , Metaplasia/pathology , Mice , Precancerous Conditions/genetics , Precancerous Conditions/immunology , Protective Factors , Protein Serine-Threonine Kinases/genetics , Signal Transduction/genetics , Signal Transduction/immunology , Stomach Neoplasms/genetics , Stomach Neoplasms/immunology , Stomach Neoplasms/pathology , Transcription Factors/metabolism , Tumor Suppressor Proteins/genetics , YAP-Signaling Proteins
12.
Cancers (Basel) ; 12(8)2020 Jul 22.
Article in English | MEDLINE | ID: mdl-32707998

ABSTRACT

Cancer stem cells (CSCs) present chemo-resistance mechanisms contributing to tumour maintenance and recurrence, making their targeting of utmost importance in gastric cancer (GC) therapy. The Hippo pathway has been implicated in gastric CSC properties and was shown to be regulated by leukaemia inhibitory factor receptor (LIFR) and its ligand LIF in breast cancer. This study aimed to determine LIF's effect on CSC properties in GC cell lines and patient-derived xenograft (PDX) cells, which remains unexplored. LIF's treatment effect on CSC markers expression and tumoursphere formation was evaluated. The Hippo kinase inhibitor XMU-MP-1 and/or the JAK1 inhibitor Ruxolitinib were used to determine Hippo and canonical JAK/STAT pathway involvement in gastric CSCs' response to LIF. Results indicate that LIF decreased tumorigenic and chemo-resistant CSCs, in both GC cell lines and PDX cells. In addition, LIF increased activation of LATS1/2 Hippo kinases, thereby decreasing downstream YAP/TAZ nuclear accumulation and TEAD transcriptional activity. LIF's anti-CSC effect was reversed by XMU-MP-1 but not by Ruxolitinib treatment, highlighting the opposite effects of these two pathways downstream LIFR. In conclusion, LIF displays anti-CSC properties in GC, through Hippo kinases activation, and could in fine constitute a new CSCs-targeting strategy to help decrease relapse cases and bad prognosis in GC.

13.
Cells ; 9(6)2020 06 13.
Article in English | MEDLINE | ID: mdl-32545795

ABSTRACT

Helicobacter pylori infection, the main risk factor for gastric cancer (GC), leads to an epithelial-mesenchymal transition (EMT) of gastric epithelium contributing to gastric cancer stem cell (CSC) emergence. The Hippo pathway effectors yes-associated protein (YAP) and transcriptional co-activator with PDZ binding motif (TAZ) control cancer initiation and progression in many cancers including GC. Here, we investigated the role of TAZ in the early steps of H. pylori-mediated gastric carcinogenesis. TAZ implication in EMT, invasion, and CSC-related tumorigenic properties were evaluated in three gastric epithelial cell lines infected by H. pylori. We showed that H. pylori infection increased TAZ nuclear expression and transcriptional enhancer TEA domain (TEAD) transcription factors transcriptional activity. Nuclear TAZ and zinc finger E-box-binding homeobox 1 (ZEB1) were co-overexpressed in cells harboring a mesenchymal phenotype in vitro, and in areas of regenerative hyperplasia in gastric mucosa of H. pylori-infected patients and experimentally infected mice, as well as at the invasive front of gastric carcinoma. TAZ silencing reduced ZEB1 expression and EMT phenotype, and strongly inhibited invasion and tumorsphere formation induced by H. pylori. In conclusion, TAZ activation in response to H. pylori infection contributes to H. pylori-induced EMT, invasion, and CSC-like tumorigenic properties. TAZ overexpression in H. pylori-induced pre-neoplastic lesions and in GC could therefore constitute a biomarker of early transformation in gastric carcinogenesis.


Subject(s)
Epithelial Cells/metabolism , Gastric Mucosa/pathology , Helicobacter Infections/metabolism , Neoplastic Stem Cells/pathology , Animals , Epithelial Cells/pathology , Epithelial-Mesenchymal Transition/physiology , Helicobacter Infections/genetics , Helicobacter Infections/pathology , Helicobacter pylori/metabolism , Humans , Hyaluronan Receptors/metabolism , Mice , Neoplastic Stem Cells/metabolism , Transcription Factors/metabolism
14.
BMC Public Health ; 9: 237, 2009 Jul 14.
Article in English | MEDLINE | ID: mdl-19602256

ABSTRACT

BACKGROUND: The association between area characteristics and birth outcomes is modified by race. Whether such associations vary according to social class indicators beyond race has not been assessed. METHODS: This study evaluated effect modification by maternal birthplace and education of the relationship between neighbourhood characteristics and birth outcomes of newborns from 1999-2003 in the province of Québec, Canada (N = 353,120 births). Areas (N = 143) were defined as administrative local health service delivery districts. Multi-level logistic regression was used to model the association between three area characteristics (median household income, immigrant density and income inequality) and the two outcomes preterm birth (PTB) and small-for-gestational age (SGA) birth. Effect modification by social class indicators was evaluated in analyses stratified according to maternal birthplace and education. RESULTS: Relative to the lowest tertile, high median household income was associated with SGA birth among Canadian-born mothers (odds ratio (OR) 1.13, 95% confidence interval (CI) 1.06, 1.20) and mothers with high school education or less (OR 1.13, 95% CI 1.02, 1.24). Associations between median household income and PTB were weaker. Relative to the highest tertile, low immigrant density was associated with a lower odds of PTB among foreign-born mothers (OR 0.79, 95% CI 0.63, 1.00) but a higher odds of PTB among Canadian-born mothers (OR 1.14, 95% CI 1.07, 1.21). Associations with income inequality were weak or absent. CONCLUSION: The association between area factors and birth outcomes is modified by maternal birthplace and education. Studies have found that race interacts in a similar manner. Public health policies focussed on perinatal health must consider the interaction between individual and area characteristics.


Subject(s)
Emigrants and Immigrants/statistics & numerical data , Health Status Disparities , Income , Infant, Small for Gestational Age , Population Density , Premature Birth/epidemiology , Adult , Educational Status , Female , Humans , Infant, Newborn , Logistic Models , Male , Mothers , Odds Ratio , Quebec/epidemiology , Residence Characteristics , Social Class , Young Adult
15.
Cancers (Basel) ; 11(4)2019 Apr 19.
Article in English | MEDLINE | ID: mdl-31010193

ABSTRACT

Gastric cancer is the third leading cause of cancer mortality worldwide. Cancer stem cells (CSC) are at the origin of tumor initiation, chemoresistance, and the formation of metastases. However, there is a lack of mouse models enabling the study of the metastatic process in gastric adenocarcinoma (GC). The aims of this study were to develop original mouse models of patient-derived primary GC orthotopic xenografts (PDOX) allowing the development of distant metastases as preclinical models to study the anti-metastatic efficiency of drugs such as the phosphatidylinositol 3-kinase (PI3K) inhibitor Buparlisib (BKM120). Luciferase-encoding cells generated from primary GC were injected into the stomach wall of immunocompromised mice; gastric tumor and metastases development were followed by bioluminescence imaging. The anti-CSC properties of BKM120 were evaluated on the GC cells' phenotype (CD44 expression) and tumorigenic properties in vitro and in vivo on BKM120-treated mice. After eight weeks, PDOX mice formed tumors in the stomach as well as distant metastases, that were enriched in CSC, in the liver, the lung, and the peritoneal cavity. BKM120 treatment significantly inhibited the CSC properties in vitro and reduced the number of distant metastases in mice. These new preclinical models offer the opportunity to study the anti-metastatic efficiency of new CSC-based therapeutic strategies.

16.
Sci Rep ; 8(1): 1667, 2018 01 26.
Article in English | MEDLINE | ID: mdl-29374231

ABSTRACT

MicroRNAs are key factors in the regulation of gene expression and their deregulation has been directly linked to various pathologies such as cancer. The use of small molecules to tackle the overexpression of oncogenic miRNAs has proved its efficacy and holds the promise for therapeutic applications. Here we describe the screening of a 640-compound library and the identification of polyamine derivatives interfering with in vitro Dicer-mediated processing of the oncogenic miR-372 precursor (pre-miR-372). The most active inhibitor is a spermine-amidine conjugate that binds to the pre-miR-372 with a KD of 0.15 µM, and inhibits its in vitro processing with a IC50 of 1.06 µM. The inhibition of miR-372 biogenesis was confirmed in gastric cancer cells overexpressing miR-372 and a specific inhibition of proliferation through de-repression of the tumor suppressor LATS2 protein, a miR-372 target, was observed. This compound modifies the expression of a small set of miRNAs and its selective biological activity has been confirmed in patient-derived ex vivo cultures of gastric carcinoma. Polyamine derivatives are promising starting materials for future studies about the inhibition of oncogenic miRNAs and, to the best of our knowledge, this is the first report about the application of functionalized polyamines as miRNAs interfering agents.


Subject(s)
Antineoplastic Agents/pharmacology , MicroRNAs/metabolism , Polyamines/pharmacology , RNA Processing, Post-Transcriptional/drug effects , Antineoplastic Agents/isolation & purification , Cell Line, Tumor , Cell Proliferation/drug effects , Drug Evaluation, Preclinical , Humans , Inhibitory Concentration 50 , Polyamines/isolation & purification , Protein Serine-Threonine Kinases/biosynthesis , Tumor Suppressor Proteins/biosynthesis
17.
Cancers (Basel) ; 10(12)2018 Dec 19.
Article in English | MEDLINE | ID: mdl-30572654

ABSTRACT

Signal transducer and activator of transcription 3 (STAT3) signaling is a major driver of colorectal cancer (CRC) growth, however therapeutics, which can effectively target this pathway, have so far remained elusive. Here, we performed an extensive screen for STAT3 inhibitors among a library of 1167 FDA-approved agents, identifying Ponatinib as a lead candidate. We found that Ponatinib inhibits STAT3 activity driven by EGF/EGFR, IL-6/IL-6R and IL-11/IL-11R, three major ligand/receptor systems involved in CRC development and progression. Ponatinib was able to inhibit CRC migration and tumor growth in vivo. In addition, Ponatinib displayed a greater ability to inhibit STAT3 activity and mediated superior anti-proliferative efficacy compared to five FDA approved SRC and Janus Kinase (JAK) inhibitors. Finally, long-term exposure of CRC cells to Ponatinib, Dasatinib and Bosutinib resulted in acquired resistance to Dasatinib and Bosutinib occurring within six weeks. However, acquired resistance to Ponatinib was observed after long-term exposure of >4 months. Overall, our results identify a novel anti-STAT3 property of Ponatinib and thus, Ponatinib offers a potential therapeutic strategy for CRC.

18.
Eur J Cancer ; 84: 193-201, 2017 10.
Article in English | MEDLINE | ID: mdl-28822889

ABSTRACT

Gastric cancer is the third leading cause of cancer-related deaths worldwide and has still a poor prognosis. Therefore, new therapeutic strategies are needed: among them, targeting cancer stem cells (CSCs) could offer new opportunities. The aim of our study was to evaluate the anti-tumoural effect of metformin on gastric cancer in vitro and in vivo and especially, to determine whether this molecule could target the gastric CSCs. Metformin effects were evaluated on the proliferation and tumourigenic properties of the gastric CSCs from patient-derived primary tumour xenografts (PDXs) and cancer cell lines (MKN45, AGS and MKN74) in vitro in conventional 2 dimensional (2D) and in 3 dimensional (3D) culture systems, in which only CSCs are able to form tumourspheres and in mouse xenograft models in vivo. Metformin induced a cell cycle arrest, which decreased cell proliferation in the 2D cultures. In a 3D culture system, metformin decreased the number of tumourspheres, revealing its capacity to target the CSCs. This effect was confirmed by the study of the expression of CSC markers (CD44 and Sox2) and differentiation markers (Kruppel-like factor 4 and MUC5AC), which were decreased or increased in response to metformin, respectively. Finally, in vivo treatment of PDXs with metformin led to a tumour growth delay and decreased the self-renewal ability of the CSCs. These results suggest that the use of metformin could represent an efficient strategy to inhibit tumour growth by targeting gastric CSCs.


Subject(s)
Antineoplastic Agents/pharmacology , Cell Differentiation/drug effects , Cell Proliferation/drug effects , Metformin/pharmacology , Neoplastic Stem Cells/drug effects , Stomach Neoplasms/drug therapy , Animals , Biomarkers, Tumor/metabolism , Cell Cycle Checkpoints/drug effects , Cell Line, Tumor , Cell Self Renewal/drug effects , Dose-Response Relationship, Drug , Humans , Hyaluronan Receptors/metabolism , Kruppel-Like Factor 4 , Kruppel-Like Transcription Factors/metabolism , Mice , Mucin 5AC/metabolism , Neoplastic Stem Cells/metabolism , Neoplastic Stem Cells/pathology , Phenotype , SOXB1 Transcription Factors/metabolism , Spheroids, Cellular , Stomach Neoplasms/metabolism , Stomach Neoplasms/pathology , Time Factors , Tumor Burden/drug effects , Tumor Cells, Cultured , Xenograft Model Antitumor Assays
19.
Clin Cancer Res ; 23(6): 1586-1597, 2017 Mar 15.
Article in English | MEDLINE | ID: mdl-27620279

ABSTRACT

Purpose: Gastric carcinomas are heterogeneous, and the current therapy remains essentially based on surgery with conventional chemotherapy and radiotherapy. This study aimed to characterize biomarkers allowing the detection of cancer stem cells (CSC) in human gastric carcinoma of different histologic types.Experimental Design: The primary tumors from 37 patients with intestinal- or diffuse-type noncardia gastric carcinoma were studied, and patient-derived tumor xenograft (PDX) models in immunodeficient mice were developed. The expressions of 10 putative cell surface markers of CSCs, as well as aldehyde dehydrogenase (ALDH) activity, were studied, and the tumorigenic properties of cells were evaluated by in vitro tumorsphere assays and in vivo xenografts by limiting dilution assays.Results: We found that a subpopulation of gastric carcinoma cells expressing EPCAM, CD133, CD166, CD44, and a high ALDH activity presented the properties to generate new heterogeneous tumorspheres in vitro and tumors in vivo CD44 and CD166 were coexpressed, representing 6.1% to 37.5% of the cells; ALDH activity was detected in 1.6% to 15.4% of the cells; and the ALDH+ cells represented a core within the CD44+/CD166+ subpopulation that contained the highest frequency of tumorigenic CSCs in vivo The ALDH+ cells possessed drug efflux properties and were more resistant to standard chemotherapy than the ALDH- cells, a process that was partially reversed by verapamil treatment.Conclusions: CD44 and ALDH are the most specific biomarkers to detect and isolate tumorigenic and chemoresistant gastric CSCs in noncardia gastric carcinomas independently of the histologic classification of the tumor. Clin Cancer Res; 23(6); 1586-97. ©2016 AACR.


Subject(s)
Aldehyde Dehydrogenase/genetics , Carcinoma/genetics , Hyaluronan Receptors/genetics , Stomach Neoplasms/genetics , Aged , Animals , Biomarkers, Tumor/genetics , Carcinogenesis/genetics , Carcinoma/pathology , Cell Lineage/genetics , Female , Humans , Male , Mice , Neoplastic Stem Cells/pathology , Stomach Neoplasms/pathology , Xenograft Model Antitumor Assays
20.
Bull Cancer ; 103(6 Suppl 1): S39-47, 2016 Jun.
Article in French | MEDLINE | ID: mdl-27494972

ABSTRACT

FUNDAMENTAL BASIS OF METASTATIC PROCESS: Metastatic process is described as a "dissemination of neoplastic cells in a distant secondary site, in which cells proliferate to develop a mass of cells partially differentiated". The vast majority of death in solid cancers is the consequence of metastasis development which lead to vital organ dysfunction. In the present review, either recent discoveries or controversial subjects associated with metastasis process will be discussed. Indeed epithelia-mesenchymal transition (EMT), circulating tumor cells, tumor dormancy, colonization in distant organ and cancer stem cells are tackled.


Subject(s)
Epithelial-Mesenchymal Transition , Neoplasm Metastasis , Neoplastic Stem Cells , Cell Adhesion , Cell Movement , Humans , Neoplasm Invasiveness , Neoplasm Metastasis/pathology , Neoplasm Metastasis/physiopathology , Neoplastic Cells, Circulating/pathology , Neoplastic Stem Cells/physiology , Organ Specificity , Tumor Microenvironment
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