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International audience; Atherosclerosis, in the ultimate stage of cardiovascular diseases, causes an obstruction of vessels leading to ischemia and finally to necrosis. To restore vascularization and tissue regeneration, stimulation of angiogenesis is necessary. Chemokines and microRNAs (miR) were studied as pro-angiogenic agents. We analysed the miR-126/CXCL12 axis and compared impacts of both miR-126-3p and miR-126-5p strands effects in CXCL12-induced angiogenesis. Indeed, the two strands of miR-126 were previously shown to be active but were never compared together in the same experimental conditions regarding their differential functions in angiogenesis. In this study, we analysed the 2D-angiogenesis and the migration assays in HUVEC in vitro and in rat's aortic rings ex vivo, both transfected with premiR-126-3p/-5p or antimiR-126-3p/-5p strands and stimulated with CXCL12. First, we showed that CXCL12 had pro-angiogenic effects in vitro and ex vivo associated with overexpression of miR-126-3p in HUVEC and rat's aortas. Second, we showed that 2D-angiogenesis and migration induced by CXCL12 was abolished in vitro and ex vivo after miR-126-3p inhibition. Finally, we observed that SPRED-1 (one of miR-126-3p targets) was inhibited after CXCL12 treatment in HUVEC leading to improvement of CXCL12 pro-angiogenic potential in vitro. Our results proved for the first time: 1-the role of CXCL12 in modulation of miR-126 expression; 2-the involvement of miR-126 in CXCL12 pro-angiogenic effects; 3-the involvement of SPRED-1 in angiogenesis induced by miR-126/CXCL12 axis.

Fucoidan is a natural sulfated polysaccharide with a large range of biological activities including anticancer and anti-oxidation activities. Hepatocellular carcinoma is the fourth most common aggressive cancer type. The aim of this study was to investigate the bioactivity of free fucoidan versus its vectorization using nanoparticles (NPs) in human hepatoma cells, Huh-7. Iron oxide NPs were functionalized with fucoidan by a one-step surface complexation. NP cellular uptake was quantified by magnetic measurement at various extracellular iron concentrations. Cell invasion and migration were reduced with NPs while free fucoidan increases these events at low fucoidan concentration (≤0.5 μM). Concomitantly, a high decrease of reactive oxygen species production related with a decrease of the matrix metalloproteinase-9 activity and an increase of its expression was observed with NPs compared to free fucoidan. A proteomic analysis evidenced that some fucoidan regulated proteins appeared, which were related to protein synthesis, N-glycan processing, and cellular stress. To our knowledge, this is the first study which reveals such activity induced by fucoidan. These results pave the way for USPIO-fucoidan-NPs as potential theranostic nanotools for hepatocellular carcinoma treatment.

International audience; Fibrosis is characterized by a pathologic deposition of collagen I, leading to impaired function of organs. Tissue biopsy is the gold standard method for the diagnosis of fibrosis but this is an invasive procedure, subject to sampling errors. Several non-invasive techniques such as magnetic resonance imaging (MRI) using non-specific probes have been developed but they are not fully satisfying as they allow diagnosis at a late stage. In this study, collagelin, a collagen-binding peptide has been covalently linked using click chemistry to pegylated Ultra Small Super Paramagnetic Iron Oxide Nanoparticles (USPIO–PO–PEG–collagelin NPs) with the aim of diagnosing fibrosis at an early stage by MRI. USPIO–PO–PEG–collagelin NPs showed a high affinity for collagen I, two times higher than that of free collagelin whereas not peptide labeled USPIO NPs (USPIO–PO–PEG-yne) did not present any affinity. NPs were not toxic for macrophages and fibroblasts. Diffusion through collagen hydrogels concentrated at 3 and 10 mg mL−1 revealed a large accumulation of USPIO–PO–PEG–collagelin NPs within the collagen network after 72 hours, ca. 3 times larger than that of unlabeled USPIO, thereby evidencing the specific targeting of collagen I. Moreover, the quantity of USPIO–PO–PEG–collagelin NPs accumulated within hydrogels was proportional to the collagen concentration. Subsequently, the NPs diffusion through collagen hydrogels was monitored by MRI. The MRI T2 time relaxation decreased much more significantly with depth for USPIO–PO–PEG–collagelin NPs compared to unlabeled ones. Taken together, these results show that USPIO–PEG–collagelin NPs are promising as effective MRI nanotracers for molecular imaging of fibrosis at an early stage.

This paper describes the preparation and the biological evaluation of α-halogenated oxaphosphinanes. These halogen derivatives were synthetized from a short and stereoselective synthetic sequence starting by previously described hydroxy-precursors 1 and 2 with respectively a glucose and mannose-like configuration. The in vitro biological tests of these unnatural halogenated phosphinosugars, on several cell lines, highlighted, for some of them, their antiproliferative and anti migration and invasion properties at nanomolar concentration.

We investigated the biological effects of new synthesized bisphosphonates (BPs) on HuH7 hepatocarcinoma cells. BPs containing p-bromophenyl (R1 = p-Br, Ph, 2) in their side chain were the more potent to inhibit HuH7 cell viability. In addition, phenyl diesterified analogues (R2 = R3 = Ph, 2a) were more potent than methyl (R2 = R3 = Me, 2b) or non-esterified BPs (2) inducing more necrosis suggesting that they better entered into cells. Phosphodiesterase inhibitor (IBMX) reversed the effect of the esterified BPs and not that of non-esterified ones suggesting role of cell phosphodiesterases to release active BPs. BP analogues inhibited HuH7 cell migration but esterified ones had no effect on invasion due to the hiding of phosphonic groups. All together, these results indicated the therapeutic interest of these new BP prodrugs.

Nanoparticle (NP) administration is among the most attractive approaches to exploit the synergy of different copackaged molecules for the same target. In this work, iron oxide NPs are surface-engineered for the copackaging of the autoantigen proinsulin, a major target of adaptive immunity in type 1 diabetes (T1D), and 2-(1'H-indole-3'-carbonyl)-thiazole-4-carboxylic acid methylester (ITE), a small drug conditioning a tolerogenic environment. Magnetic resonance imaging (MRI) combined with magnetic quantification are used to investigate NP biokinetics in nonobese diabetic (NOD) mice and control mice in different organs. Different NP biodistribution, with in particular enhanced kidney elimination and a stronger accumulation in the pancreas for prediabetic NOD mice, is observed. This is related to preferential NP accumulation in the pancreatic inflammatory zone and to enhancement of renal elimination by diabetic nephropathy. For both mouse strains, an MRI T2 contrast enhancement at 72 h in the liver, pancreas, and kidneys, and indicating recirculating NPs, is also found. This unexpected result is confirmed by magnetic quantification at different time points as well as by histological evaluation. Besides, such NPs are potential MRI contrast agents for early diagnosis of T1D.

1 - Article; Bisphosphonates have been used for decades in the standard therapy of bone-related diseases, including bone metastasis of various malignancies, and they might as well be toxic on early cancer cells themselves. In order to allow a better delivery of neridronate (a N-containing bisphosphonate with relatively poor activity), liposomes were evaluated in vitro on cancer cell lines (MDA-MB 231, U87-MG and Caco2). After chemical synthesis, this water-soluble molecule was encapsulated into liposomes containing DOPC:DOPG:Chol (72:27:1 molar ratio). The influence of neridronate (free or liposomal) on cell viability or proliferation after treatment was evaluated using the MTT method, as well as cell migration and invasion assays; these techniques showed a drastic improvement of the action of neridronate on MDA-MB-231 cells with an EC50 fifty times lower when neridronate was encapsulated. Internalization of liposomes was followed by flow cytometry and fluorescence microscopy, demonstrating internalization via the endocytic pathway. Furthermore, since over-expression of matrix metalloproteinases (particularly MMP-2 and MMP-9) has been correlated to poor prognosis in many cancer types, detection of MMP expression is a satisfactory indication of the therapy efficiency and was then performed on treated cells. On MDA-MB-231 cells, MPPs expression was also significantly reduced by neridronate while entrapped in liposomes.

In addition to their physiologic effects in inflammation and angiogenesis, chemokines are involved in cancer pathology. The aim of this study was to determine whether the chemokine stromal cell–derived factor 1 (SDF-1) induces the growth, migration, and invasion of human hepatoma cells. We show that SDF-1 G protein–coupled receptor, chemokine (C-X-C motif) receptor 4 (CXCR4), and SDF-1 mRNA are expressed in human hepatoma Huh7 cells, which secrete and bind SDF-1. This binding depends on CXCR4 and glycosaminoglycans. SDF-1 associates with CXCR4, and syndecan-4 (SDC-4), a heparan sulfate proteoglycan at the plasma membrane of Huh7 cells, induces the growth of Huh7 cells by promoting their entry into the cell cycle, and inhibits the tumor necrosis factor-α–mediated apoptosis of the cells. SDF-1 also reorganizes Huh7 cytoskeleton and induces tyrosine phosphorylation of focal adhesion kinase. Finally, SDF-1 activates matrix metalloproteinase-9, resulting in increased migration and invasion of Huh7 cells. These biological effects of SDF-1 were strongly inhibited by the CXCR4 antagonist AMD3100, by a glycosaminoglycan, heparin, as well as by β-d-xyloside treatment of the cells, or by c-jun NH2-terminal kinase/stress-activated protein kinase inhibitor. Therefore, the CXCR4, glycosaminoglycans, and the mitogen-activated protein kinase signaling pathways are involved in these events. The fact that reducing SDC-4 expression by RNA interference decreased SDF-1–induced Huh7 hepatoma cell migration and invasion strongly indicates that SDC-4 may be an auxiliary receptor for SDF-1. Finally, the fact that CXCR4 is expressed in hepatocellular carcinoma cells from liver biopsies indicates that the in vitro results reported here could be extended to in vivo conditions. (Mol Cancer Res 2007;5(1):21–33)

Bisphosphonates (BPs) have interesting antitumor effects as well in vitro as in vivo, despite their poor bioavailability in the organism after oral ingestion. To overcome this problem and reduce drug doses and secondary effects, we report the chemical synthesis of new bioconjugates. They were built with a nitrogen-containing BP as the drug covalently coupled to the carboxymethyldextran. This polysaccharide was used as a carrier, in order to increase BP lifetime in bloodstream and to target tumor cells which have a strong affinity with dextran. The efficiency of our vectorization system was biologically proved in vitro and in vivo on mammalian carcinoma models in mice.

International audience; This paper reports the design and the synthesis of a new family of compounds, the phostines, belonging to the [1,2]oxaphosphinane family. Twenty-six compounds have been screened for their antiproliferative activity against a large panel of NCI cancer cell lines. Because of its easy synthesis and low EC50 value (500 nM against the C6 rat glioma cell line), compound 3.1a was selected for further biological study. Moreover, the specific biological effect of 3.1a on the glioblastoma phylogenetic cluster from the NCI is dependent on its stereochemistry. Within that cluster, 3.1a has a higher antiproliferative activity than Temozolomide and is more potent than paclitaxel for the SF295 and SNB75 cell lines. In constrast with paclitaxel and vincristine, 3.1a is devoid of astrocyte toxicity. The original activity spectrum of 3.1a on the NCI cancer cell line panel allows the development of this family for use in association with existing drugs, opening new therapeutic perspectives.

1 - Article; Introduction: The poor efficacy of various anti-cancer treatments against metastatic cells has focused attention on the role of tumor microenvironment in cancer progression. To understand the contribution of the extracellular matrix (ECM) environment to this phenomenon, we isolated ECM surrogate invading cell populations from MDA-MB-231 breast cancer cells and studied their genotype and malignant phenotype. Methods: We isolated invasive subpopulations (INV) from non invasive populations (REF) using a 2D-Matrigel assay, a surrogate of basal membrane passage. INV and REF populations were investigated by microarray assay and for their capacities to adhere, invade and transmigrate in vitro, and to form metastases in nude mice. Results: REF and INV subpopulations were stable in culture and present different transcriptome profiles. INV cells were characterized by reduced expression of cell adhesion and cell-cell junction genes (44% of down regulated genes) and by a gain in expression of anti-apoptotic and pro-angiogenic gene sets. In line with this observation, in vitro INV cells showed reduced adhesion and increased motility through endothelial monolayers and fibronectin. When injected into the circulation, INV cells induced metastases formation, and reduced injected mice survival by up to 80% as compared to REF cells. In nude mice, INV xenografts grew rapidly inducing vessel formation and displaying resistance to apoptosis. Conclusion: Our findings reveal that the in vitro ECM microenvironment per se was sufficient to select for tumor cells with a stable metastatic phenotype in vivo characterized by loss of adhesion molecules expression and induction of proangiogenic and survival factors.

International audience; Zosterin, an apiose-rich pectic polysaccharide, was extracted and purified from the sea grass Zostera marina. Structural studies conducted by gas chromatography and NMR spectroscopy on a purified zosterin fraction (AGU) revealed a typical apiogalacturonan structure comprising an α-1,4-d- galactopyranosyluronan backbone substituted by 1,2-linked apiofuranose oligosaccharides and single apiose residues. The average molecular mass of AGU was estimated to be about 4100 Da with a low polydispersity. AGU inhibited proliferation of A431 human epidermoid carcinoma cells with an approximate IC50 value of 3 μg/mL (0.7 μM). In addition, AGU inhibited A431 cell migration and invasion. Preliminary experiments showed that inhibition of metalloproteases expression could play a role in these antimigration and anti-invasive properties. Autohydrolysis of AGU, which eliminated apiose and oligo-apiose substituents, led to a virtual disappearance of cytotoxic properties, thus suggesting a direct structure-function relationship with the apiose-rich hairy region of AGU.

The synthesis and biological activity of chloroethyl pyrimidine nucleosides is presented. One of these new nucleosides analogues significantly inhibited cell proliferation, migration and invasion as tested in vitro on the A431 vulvar epidermal carcinoma cell line.

International audience; The synthesis and biological activity of chloroethyl pyrimidine nucleosides is presented. One of these new nucleosides analogues significantly inhibited cell proliferation, migration and invasion as tested in vitro on the A431 vulvar epidermal carcinoma cell line.

International audience; The synthesis and biological activity of a novel DNA cross-linking antitumor agent is presented. The new alkylating agent significantly inhibited cell proliferation, migration and invasion as tested in vitro on the A431 vulvar epidermal carcinoma cell line.

International audience; Xylans were purified from delignified holocellulose alkaline extracts of Castanea sativa (Spanish chestnut) and Argania spinosa (Argan tree) and their structures analyzed by means of GC of their per-trimethylsilylated methylglycoside derivatives and (1)H NMR spectroscopy. The structures deduced were characteristic of a 4-O-methylglucuronoxylan (MGX) and a homoxylan (HX), respectively, with degrees of polymerization ranging from 182 to 360. In the case of MGX, the regular or random distribution of 4-O-methylglucuronic acid along the xylosyl backbone--determined by MALDI mass spectrometry after autohydrolysis of the polysaccharide--varied and depended both on the botanical source from which they were extracted and on the xylan extraction procedure. The MGX also inhibited in different ways the proliferation as well as the migration and invasion capability of A431 human epidermoid carcinoma cells. These biological properties could be correlated with structural features including values of the degree of polymerization, 4-O-MeGlcA to xylose ratios, and distribution of 4-O-MeGlcA along the xylosyl backbone, giving evidence of a defined structure-activity relationship.

The CC-chemokine regulated on activation, normal T-cell expressed, and presumably secreted (RANTES)/CCL5 mediates its biological activities through activation of G protein–coupled receptors, CCR1, CCR3, or CCR5, and binds to glycosaminoglycans. This study was undertaken to investigate whether this chemokine is involved in hepatoma cell migration or invasion and to modulate these effects in vitro by the use of glycosaminoglycan mimetics. We show that the human hepatoma Huh7 and Hep3B cells express RANTES/CCL5 G protein–coupled receptor CCR1 but not CCR3 nor CCR5. RANTES/CCL5 binding to these cells depends on CCR1 and glycosaminoglycans. Moreover, RANTES/CCL5 strongly stimulates the migration and the invasion of Huh7 cells and to a lesser extent that of Hep3B cells. RANTES/CCL5 also stimulates the tyrosine phosphorylation of focal adhesion kinase and activates matrix metalloproteinase-9 in Huh7 hepatoma cells, resulting in increased invasion of these cells. The fact that RANTES/CCL5-induced migration and invasion of Huh7 cells are both strongly inhibited by anti-CCR1 antibodies and heparin, as well as by β-d-xyloside treatment of the cells, suggests that CCR1 and glycosaminoglycans are involved in these events. We then show by surface plasmon resonance that synthetic glycosaminoglycan mimetics, OTR4120 or OTR4131, directly bind to RANTES/CCL5. The preincubation of the chemokine with each of these mimetics strongly inhibited RANTES-induced migration and invasion of Huh7 cells. Therefore, targeting the RANTES-glycosaminoglycan interaction could be a new therapeutic approach for human hepatocellular carcinoma. [Mol Cancer Ther 2007;6(11):2948–58]

Summary Introduction Investigation of the role of vascular endothelial growth factor-C (VEGF-C) and VEGF receptor-3 (VEGFR-3) in non-small-cell lung cancer (NSCLC) has mainly focused on lymph node (LN) metastasis related to lymphangiogenesis. However, the coexpression of VEGF-C/VEGFR-3 by tumour cells can independently play an important role. The present study was therefore designed to evaluate VEGF-C/VEGFR-3 coexpression in tumour cells from the primary tumour and corresponding LN metastases. Methods VEGF-C and VEGFR-3 expression in cancer cells were evaluated by immunohistochemistry in 92 NSCLC samples and 45 metastatic LNs. Ki67 expression and mitotic index (MI) in tumours and clinicopathological data were analysed concurrently. Results VEGFR-3 and VEGF-C expression were observed in 42% and 74% of tumours, respectively. Concurrent expression of VEGF-C and VEGFR-3, observed in 39% of tumours, was significantly associated with a higher proliferation rate and a higher incidence of LN metastases. VEGF-C expression in tumour cells was observed in 100% of metastatic LN and VEGF-C/VEGFR-3 coexpression was observed in 71% of metastatic LN. Finally, concurrent expression of VEGF-C/VEGFR-3 in the primary tumour was associated with poor disease-free survival on univariate analysis. Conclusion In NSCLC cancer cells, VEGF-C/VEGFR-3 coexpression suggests an autocrine/paracrine loop responsible for a high proliferation rate in tumour cells. As VEGF-C/VEGFR-3 coexpression is very frequent in metastatic LN tumour cells, it can be hypothesised that this coexpression participates in the growth of LN metastasis.

International audience; A glucuronoxylan was purified from a delignified holocellulose alkaline extract of Castanea sativa (Spanish chestnut) and its structure analyzed by means of FT-IR, GC of the per-trimethylsilylated methylglycoside derivatives, and 1H and 13C NMR spectroscopy. The results supported a structure based on a linear polymer of xylopyranose units linked with beta(1-->4) bonds in which, on average, one out of every six units is substituted at C-2 by a 4-O-methylglucuronic acid unit; this structure is typical of a hardwood acidic 4-O-methylglucuronoxylan (MGX) with an estimated degree of polymerization of 200. The MGX from C. sativa inhibited the proliferation of A431 human epidermoid carcinoma cells with an IC50 value of 50 microM. In addition, this xylan inhibited A431 cell migration and invasion. Preliminary experiments showing that secretion of metalloproteinases MMP2 and MMP9 by A431 tumor cells was inhibited by the purified C. sativa MGX strongly suggest that this mechanism of action may play a role in its antimigration and anti-invasive properties.

International audience; The capsular polysaccharide produced by the thermophilic blue green alga/cyanobacterium Mastigocladus laminosus was tested for its cytotoxic activity against the A431 human epidermoid carcinoma cell line. This polysaccharide inhibited the proliferation of A431 cells in a dose-dependent manner with an IC (50) value of 50 microg mL (-1). In addition, this polysaccharide strongly inhibited A431 cell migration and invasion. Preliminary experiments showing that secretion of metalloproteinases MMP2 and MMP9 by A431 tumour cells was inhibited by this polysaccharide suggest that this mechanism of action could play a role in its anti-migration and anti-invasive properties. Acid hydrolysis of the polysaccharide produced specific oligosaccharides which conserved - at similar concentrations - their cytotoxic, anti-migration and anti-invasion properties; in this case, the mechanism of action was nevertheless uncorrelated to the decrease of metalloproteinase expression.

Bisphosphonates are extensively used in the treatment of patients with metastasis-induced osteolysis. The major drawback in the efficacy of all bisphosphonates lies in their high hydrophilic nature, which results in poor membrane permeability and low availability for soft tissues. A reasonable approach to overcome these problems consists in masking one or more ionizable groups of bisphosphonates, notably by esterification of the hydroxyl functions. We have previously shown that the novel non-nitrogen-containing bisphosphonate BP7033 inhibited angiogenesis and growth of primary tumors in nude mice. The present study focuses on the dimethyl-esterified analog of this compound (Me-BP7033). In-vitro, Me-BP7033 inhibited proliferation of human carcinoma A431 cells as well as their invasive activity based on a transwell invasion assay. in-vivo, administration of Me-BP7033 (0.3 mg/kg) twice a week for 5 weeks inhibited the tumor growth of A431 cells xenografted in nude mice by 65%. Immunostaining of endothelial cells (ECs) in tumor sections revealed that Me-BP7033 inhibited the intratumor ECs density by 60%. The in-vivo anti-angiogenic properties of Me-BP7033 were also demonstrated in an in-vivo angiogenesis assay showing that Me-BP7033 reduced the vascular endothelial growth factor-stimulated infiltration of ECs in a Matrigel plug by 70%. In summary, we demonstrated for the first time that a diesterified bisphosphonate exhibited in vivo both anti-tumoral and anti-angiogenic activities with no apparent sign of toxic effects. These new diesterified compounds, which could display enhanced bioavailability and pharmacokinetics, thus represent interesting candidates for therapeutic applications such as cancer treatment.