128 research outputs found

    TGF-B induced protein IG-H3 is essential for the growth of human liver metastases

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    Introduction : Transforming growth factor-beta-induced protein ig-h3 (TGFBI) is extracellular matrix component known to be important for cell-collagen interaction. We and others have reported elevated expression of TGFBI in sev- eral human cancers, where its role remains controversial. Aim Current study aims at clarifying the function of TGFBI to date. Methods &Results : CRC-LM and in liver metastases originating from breast, lung and pancreatic tumors. We have next focused on func- tional aspects and have silenced TGFBI expression in SW1222 human colorectal carcinoma cells. The suppression of TGFBI protein led to a marked decrease in cell migration (-70%) and proliferation (-30%) in vitro. To study the effects in vivo we have developed a novel animal model of colorectal carcinoma based on chicken chorioallantoic membrane (CAM) that mimics human CRC-LM. TGFBI silencing resulted in 50% reduction of tumor volume in the CAM tumor model. Notably, the tumors displayed a marked inhibition of vascularization, suggesting an additional anti-angiogenic effect. Indeed, SW1222 cells silenced for TGFBI expression secreted lower levels of VEGFA in vitro. Finally, we have investigated if TGFBI can be used as systemically reachable target for antibody-drug delivery. For this purpose we have The in vivo data demonstrated that TGFBI is an accessible tumor target. Conclusions : Taken together, the present study shows that TGFBI is essential for promoting the development of CRC- LM and therefore represents a promising target for designing novel therapeutic approaches

    Identification of novel accessible proteins bearing diagnostic and therapeutic potential in human pancreatic ductal adenocarcinoma

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    Pancreas ductal adenocarcinoma (PDAC) remains a deadly malignancy with poor early diagnostic and no effective therapy. Although several proteomic studies have performed comparative analysis between normal and malignant tissues, there is a lack of clear characterization of proteins that could be of clinical value. Systemically reachable ("potentially accessible") proteins, suitable for imaging technologies and targeted therapies represent a major group of interest. The current study explores potentially accessible proteins overexpressed in PDAC, employing innovative proteomics technologies. In the discovery phase, potentially accessible proteins from fresh human normal and PDAC tissues were ex vivo biotinylated, isolated and identified using 2D-nano-HPLC-MS/MS method. The analysis revealed 422 up-regulated proteins in the tumor, of which 83 (including protein isoforms) were evaluated as potentially accessible. Eleven selected candidates were further confirmed as up-regulated using Western blot and multiple reaction monitoring protein quantification. Of these, transforming growth factor beta-induced (TGFBI), latent transforming growth factor beta binding 2 (LTBP2), and asporin (ASPN) were further investigated by employing large scale immunohistochemistry-based validations. They were found to be significantly expressed in a large group of clinical PDAC samples compared to corresponding normal and inflammatory tissues. In conclusion, TGFBI, LTBP2, and ASPN are novel, overexpressed, and potentially accessible proteins in human PDAC. They bear the potential to be of clinical value for diagnostic and therapeutic applications and merit further studies using in vivo models. Peer reviewe

    Myoferlin: an indispensable component in VEGFA secretion by pancreas cancer cells

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    In this poster, our laboratory showed the importance of myoferlin, a biomarker of pancreas cancer, in the controle of VEGF-A mediated angiogenesis. Our laboratory showed that silencing myoferlin in pancreas cancer cells, BxPC-3, provoques a decrease in cell prolifération in vitro and a decrease in tumor volumes in animal model. Myoferlin silencing also provokes a decrease in VEGF-A secretion in the conditioned medium and that decrease was abserved in the animal model as a decrease in microvessels dencity. It appeared that this decrease in secretion is due to a a blockage in the exocytosis. Our data also showed a significate correlation between myoferlin expression and microvessels density in patients section

    Asporin Is a Fibroblast-Derived TGF-beta1 Inhibitor and a Tumor Suppressor Associated with Good Prognosis in Breast Cancer.

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    BACKGROUND: Breast cancer is a leading malignancy affecting the female population worldwide. Most morbidity is caused by metastases that remain incurable to date. TGF-beta1 has been identified as a key driving force behind metastatic breast cancer, with promising therapeutic implications. METHODS AND FINDINGS: Employing immunohistochemistry (IHC) analysis, we report, to our knowledge for the first time, that asporin is overexpressed in the stroma of most human breast cancers and is not expressed in normal breast tissue. In vitro, asporin is secreted by breast fibroblasts upon exposure to conditioned medium from some but not all human breast cancer cells. While hormone receptor (HR) positive cells cause strong asporin expression, triple-negative breast cancer (TNBC) cells suppress it. Further, our findings show that soluble IL-1beta, secreted by TNBC cells, is responsible for inhibiting asporin in normal and cancer-associated fibroblasts. Using recombinant protein, as well as a synthetic peptide fragment, we demonstrate the ability of asporin to inhibit TGF-beta1-mediated SMAD2 phosphorylation, epithelial to mesenchymal transition, and stemness in breast cancer cells. In two in vivo murine models of TNBC, we observed that tumors expressing asporin exhibit significantly reduced growth (2-fold; p = 0.01) and metastatic properties (3-fold; p = 0.045). A retrospective IHC study performed on human breast carcinoma (n = 180) demonstrates that asporin expression is lowest in TNBC and HER2+ tumors, while HR+ tumors have significantly higher asporin expression (4-fold; p = 0.001). Assessment of asporin expression and patient outcome (n = 60; 10-y follow-up) shows that low protein levels in the primary breast lesion significantly delineate patients with bad outcome regardless of the tumor HR status (area under the curve = 0.87; 95% CI 0.78-0.96; p = 0.0001). Survival analysis, based on gene expression (n = 375; 25-y follow-up), confirmed that low asporin levels are associated with a reduced likelihood of survival (hazard ratio = 0.58; 95% CI 0.37-0.91; p = 0.017). Although these data highlight the potential of asporin to serve as a prognostic marker, confirmation of the clinical value would require a prospective study on a much larger patient cohort. CONCLUSIONS: Our data show that asporin is a stroma-derived inhibitor of TGF-beta1 and a tumor suppressor in breast cancer. High asporin expression is significantly associated with less aggressive tumors, stratifying patients according to the clinical outcome. Future pre-clinical studies should consider options for increasing asporin expression in TNBC as a promising strategy for targeted therapy

    The Anti-Tumor Effect of HDAC Inhibition in a Human Pancreas Cancer Model Is Significantly Improved by the Simultaneous Inhibition of Cyclooxygenase 2

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    Pancreatic ductal adenocarcinoma is the fourth leading cause of cancer death worldwide, with no satisfactory treatment to date. In this study, we tested whether the combined inhibition of cyclooxygenase-2 (COX-2) and class I histone deacetylase (HDAC) may results in a better control of pancreatic ductal adenocarcinoma. The impact of the concomitant HDAC and COX-2 inhibition on cell growth, apoptosis and cell cycle was assessed first in vitro on human pancreas BxPC-3, PANC-1 or CFPAC-1 cells treated with chemical inhibitors (SAHA, MS-275 and celecoxib) or HDAC1/2/3/7 siRNA. To test the potential antitumoral activity of this combination in vivo, we have developed and characterized, a refined chick chorioallantoic membrane tumor model that histologically and proteomically mimics human pancreatic ductal adenocarcinoma. The combination of HDAC1/3 and COX-2 inhibition significantly impaired proliferation of BxPC-3 cells in vitro and stalled entirely the BxPC-3 cells tumor growth onto the chorioallantoic membrane in vivo. The combination was more effective than either drug used alone. Consistently, we showed that both HDAC1 and HDAC3 inhibition induced the expression of COX-2 via the NF-kB pathway. Our data demonstrate, for the first time in a Pancreatic Ductal Adenocarcinoma (PDAC) model, a significant action of HDAC and COX-2 inhibitors on cancer cell growth, which sets the basis for the development of potentially effective new combinatory therapies for pancreatic ductal adenocarcinoma patients.Peer reviewe

    A new murine model of osteoblastic/osteolytic lesions from human androgen-resistant prostate cancer

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    BACKGROUND: Up to 80% of patients dying from prostate carcinoma have developed bone metastases that are incurable. Castration is commonly used to treat prostate cancer. Although the disease initially responds to androgen blockade strategies, it often becomes castration-resistant (CRPC for Castration Resistant Prostate Cancer). Most of the murine models of mixed lesions derived from prostate cancer cells are androgen sensitive. Thus, we established a new model of CRPC (androgen receptor (AR) negative) that causes mixed lesions in bone. METHODS: PC3 and its derived new cell clone PC3c cells were directly injected into the tibiae of SCID male mice. Tumor growth was analyzed by radiography and histology. Direct effects of conditioned medium of both cell lines were tested on osteoclasts, osteoblasts and osteocytes. RESULTS: We found that PC3c cells induced mixed lesions 10 weeks after intratibial injection. In vitro, PC3c conditioned medium was able to stimulate tartrate resistant acid phosphatase (TRAP)-positive osteoclasts. Osteoprotegerin (OPG) and endothelin-1 (ET1) were highly expressed by PC3c while dikkopf-1 (DKK1) expression was decreased. Finally, PC3c highly expressed bone associated markers osteopontin (OPN), Runx2, alkaline phosphatase (ALP), bone sialoprotein (BSP) and produced mineralized matrix in vitro in osteogenic conditions. CONCLUSIONS: We have established a new CRPC cell line as a useful system for modeling human metastatic prostate cancer which presents the mixed phenotype of bone metastases that is commonly observed in prostate cancer patients with advanced disease. This model will help to understand androgen-independent mechanisms involved in the progression of prostate cancer in bone and provides a preclinical model for testing the effects of new treatments for bone metastases

    Early response of lymphocyte proteins after γ-irradiation of human whole blood and their dose-dependence – prerequisite for the development of individual biodosimeter

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    The present thesis is concerned with the issues involved in obtaining reliable experimental data permitting a retrospective assessment of radiation-induced doses at the time of application or contamination. In order to provide prompt medical treatment of those injured in accidents with ionizing radiation, biological procedures that can be implemented swiftly and at an early stage are required both to determine the radiation dose originally received as well as to assess the course of the dose-dependent biological reactions on the basis of individual sensitivity to radiation. To this end, in the present thesis the lymphocyte proteins (phosphoproteins and total proteins) in blood taken from test subjects who had been exposed to γ-radiation (applied dose: 0-4 Gy) were analysed just 15 minutes after completing irradiation by means of 2D gel electrophoresis. Only those early-response proteins (ERPROs) that displayed a significant radiation-induced change were identified by nano-HPLC-MS/MS. For validation purposes, the dose-dependent gene expression of some of these proteins was determined by RT-qPCR. The following ERPROs displayed pronounced early reactions in the form of changes of concentration in comparison to unirradiated control samples: talin-1, talin-2, β-actin, mutant β-actin, peroxin-1 and also the phosphoproteins annexin-A6, MHC-binding protein-2, zyxin-2, interleukin-17E and phosphoglycerate kinase-1. The majority of the lymphocyte ERPROs represent proteins responsible for changes to the cytoskeleton, proliferation and cell cycle, modulation of immunoreactions as well as protein degradation and energy production. Other cellular processes may not have been determined due to the sensitivity restrictions of the 2D-PAGE and MS methods, but cannot be excluded. Gene expression studies revealed that a combination of methods, comprising RT-qPCR and 2D-PAGE as well as DNA microarray and Western blot, may in future be able to overcome these restrictions. The slopes of the curves from concentration measurements of various early response proteins after doses had been applied in the 0 and 4 Gy range yielded a characteristic arrangement or pattern representative of an individual. In case of contamination, this pattern prepared ex vivo serves as a reference for identifying the originally unknown dose, thus creating the necessary condition for applying an individual radiation biodosimeter. This thus provides for the first time an experimental means of biologically quantifying in retrospect radioactive doses in the 0 and 4 Gy range after a relatively short time

    Collaborative and Defensive Fibroblasts in Tumor Progression and Therapy Resistance

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    International audienceTumor microenvironment is a complex network of epithelial cancer cells and non-transformed stromal cells. Of the many stromal cell types, fibroblasts are the most numerous ones and are traditionally viewed as supportive elements of cancer progression. Many studies show that cancer cells engage in active crosstalk with associated fibroblasts in order to obtain key resources, such as growth factors and nutrients. The facets of fibroblast "complicity to murder" in cancer are multiple. However, recent therapeutic attempts aiming at depleting fibroblasts from tumors, perturbed rather simplistic picture. Contrary to the expectations, tumors devoid of fibroblasts accelerated their progression while patients faced poorer outcomes. These studies remind us of the physiologic roles fibroblasts have in maintaining tissue homeostasis even in the presence of cancer. It is becoming increasingly clear that our research focus on advanced tumors has biased our understanding of fibroblast role in tumor biology. The numerous events where the fibroblasts protect the tissue from malignant transformation remain largely unacknowledged, as the tumors are invisible. The present review has the ambition to offer a more balanced view of fibroblasts functions in cancer progression and therapy resistance. We will address the question whether it is possible to synergize the efforts with fibroblasts as the therapeutic concept against tumor progression and therapy resistance
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