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Human Pancreatic Cancer Cells (human + pancreatic_cancer_cell)
Terms modified by Human Pancreatic Cancer Cells Selected AbstractsPeriostin, secreted from stromal cells, has biphasic effect on cell migration and correlates with the epithelial to mesenchymal transition of human pancreatic cancer cellsINTERNATIONAL JOURNAL OF CANCER, Issue 12 2008Atsushi Kanno Abstract Periostin is a secretory protein that has been suggested to function as a cell adhesion molecule and promote the invasiveness or growth rate of tumors. However, little is known about the association of its expression and epithelial to mesenchymal transition (EMT), which is considered to play a crucial role in cancer cell metastasis. Thus, the authors investigated whether periostin could be involved in the process of EMT and the role of this gene in pancreatic cancer development. The expression of periostin was observed mainly in stromal cells but very little in cancer cells by immunohistochemistry and real-time RT-PCR. In vitro, pancreatic stellate cells (PSCs) exhibited a much higher basal expression of periostin compared with cancer cells. Periostin secreted in the supernatant from 293T cells that expressed periostin (approximately 150 ng/ml) inhibited the migration of pancreatic cancer cells. Coculture assay revealed that periostin expression in PSC was induced by pancreatic cancer cells. To assess the direct role of periostin in pancreatic cancer cells, the authors generated pancreatic cancer cell lines that stably express periostin. The induced expression of periostin (to 150 ng/ml) altered the morphology of cancer cells, changing them from mesenchymal to epithelial phenotypes with the induction of epithelial markers and a reduction of mesenchymal markers, and showed reduced cell migration in vitro and formed smaller tumors as well as suppressed metastasis in vivo. On the other hand, high concentration of recombinant periostin (1 ,g/ml) promoted cell migration with AKT activation. The findings suggest that periostin has biphasic effect on the development of pancreatic cancer. © 2008 Wiley-Liss, Inc. [source] Cytotoxic action of phorbol esters on human pancreatic cancer cellsINTERNATIONAL JOURNAL OF CANCER, Issue 7 2007Jane A. Bond Abstract We previously showed that phorbol esters are cytotoxic to human thyroid epithelial cells expressing a mutant RAS oncogene. Here we explore the generality of this finding using cells derived from pancreatic cancer, which, like thyroid, shows a high frequency of RAS mutation, but is a much greater cause of cancer mortality. The response to phorbol myristate acetate (PMA) and related agents was assessed on a panel of 9 pancreatic cancer cell lines, using a range of assays for cell growth and death in vitro and in vivo. In most lines, PMA induced non-apoptotic cell death which was, surprisingly, independent of its "classic" target, protein kinase C. With 24 hr exposure, the IC50 in the most sensitive line (Aspc-1) was <1 ng/ml (1.6 nM), with survival undetectable at concentrations ,,16 nM, and after only 1 hr exposure the IC50 was still ,,16 nM. Interestingly, the efficacy of a second phorbol ester, phorbol dibutyrate, was much lower, and the PMA analogue bryostatin-1, which is in clinical trials against other tumour types, was totally inactive. Pre-treatment of Aspc-1 cells with PMA before subcutaneous inoculation into nude mice prevented, or greatly retarded, subsequent xenograft tumour growth. Furthermore, treatment of established tumours with a single peri-tumoral injection of PMA induced extensive cell death and arrested tumour development. Taken together with recent Phase 1 clinical studies, these data suggest that activity against pancreatic cancer will be attainable by systemic administration of PMA, and point to potential novel therapeutic targets for this highly aggressive cancer. © 2007 Wiley-Liss, Inc. [source] In vivo antitumor effect of the mTOR inhibitor CCI-779 and gemcitabine in xenograft models of human pancreatic cancerINTERNATIONAL JOURNAL OF CANCER, Issue 9 2006Daisuke Ito Abstract Mammalian target of rapamycin (mTOR) is considered to be a major effector of cell growth and proliferation that controls protein synthesis through a large number of downstream targets. We investigated the expression of the phosphatidylinositol 3,-kinase (PI3K)/mTOR signaling pathway in human pancreatic cancer cells and tissues, and the in vivo antitumor effects of the mTOR inhibitor CCI-779 with/without gemcitabine in xenograft models of human pancreatic cancer. We found that the Akt, mTOR and p70 S6 kinase (S6K1) from the PI3K/mTOR signaling pathway were activated in all of the pancreatic cancer cell lines examined. When surgically resected tissue specimens of pancreatic ductal adenocarcinoma were examined, phosphorylation of Akt, mTOR and S6K1 was detected in 50, 55 and 65% of the specimens, respectively. Although CCI-779 had no additive or synergistic antiproliferative effect when combined with gemcitabine in vitro, it showed significant antitumor activity in the AsPC-1 subcutaneous xenograft model as both a single agent and in combination with gemictabine. Furthermore, in the Suit-2 peritoneal dissemination xenograft model, the combination of these 2 drugs achieved significantly better survival when compared with CCI-779 or gemcitabine alone. These results demonstrate promising activity of the mTOR inhibitor CCI-779 against human pancreatic cancer, and suggest that the inhibition of mTOR signaling can be exploited as a potentially tumor-selective therapeutic strategy. © 2005 Wiley-Liss, Inc. [source] Cytotoxic T lymphocyte mediated recognition of human pancreatic cancer cellsINTERNATIONAL JOURNAL OF CANCER, Issue 1 2002Matthias Peiper Abstract T lymphocytes play an important role in tumor rejection and their response to human malignant melanoma has been well documented. In contrast, the existence of cytotoxic T lymphocytes (CTL) to pancreatic cancer remains unclear. Tumor-associated lymphocytes (TAL) and peripheral blood monocytes (PBMC) were isolated from pancreatic cancer patients. Tumor-specific CTL were generated from TAL and PBMC using solid-phase anti-CD3, low-dose IL-2 (50 IU/ml) and repetitive autologous tumor stimulation. The specificity of CTL was tested in standard cytotoxicity assays using autologous tumor cells, autologous fibroblasts when available, several allogeneic pancreatic tumor cells and the NK-sensitive cell line K562. Anti-HLA-Class I MAb, W6/32, was used to demonstrate that tumor-specific CTL were HLA-Class I restricted. HLA-molecules of human pancreatic cancer cells were washed out using acid elution. Eight consecutive, histologically confirmed pancreatic cancer specimen as well as peripheral blood mononuclear cells were analyzed. CTL were capable of lysing autologous tumor cells significantly after 3 stimulations with autologous tumor cells. T cell mediated recognition was HLA-Class I restricted as shown by incubation with MAb anti-HLA-Class I. In case of HLA-A2 positivity, incubation of tumor cells in cytotoxicity assays resulted in significant inhibition. Autologous fibroblasts or K562 cells were lysed significantly less. HLA-Class I molecule elution resulted in significantly lower recognition of these cells by CTL. These results show for the first time in a larger series the possibility of generating CTL in human pancreatic cancer. The identification of new tumor associated antigens or tumor antigens will be crucial for establishing new treatment strategies. © 2002 Wiley-Liss, Inc. [source] bcl-2-specific siRNAs restore Gemcitabine sensitivity in human pancreatic cancer cellsJOURNAL OF CELLULAR AND MOLECULAR MEDICINE, Issue 2 2007Kinya Okamoto Abstract Gemcitabine has been shown to ameliorate disease related symptoms and to prolong overall survival in pancreatic cancer.Yet, resistance to Gemcitabine is commonly observed in this tumour entity and has been linked to increased expression of anti-apoptotic bcl-2. We therefore investigated if and to what extend silencing of bcl-2 by specific siRNAs (siBCL2) might enhance Gemcitabine effects in human pancreatic carcinoma cells. siBCL2 was transfected into the pancreatic cancer cell line YAP C alone and 72 hrs before co-incubation with different concentrations of Gemcitabine. Total protein and RNA were extracted for Western-blot analysis and quantitative polymerase chain reaction. Pancreatic cancer xenografts in male nude mice were treated intraperitoneally with siBCL2 alone, Gemcitabine and control siRNA or Gemcitabine and siBCL2 for 21 days. Combination of both methods lead to a synergistic induction of apoptosis at otherwise ineffective concentrations of Gemcitabine. Tumour growth suppression was also potentiated by the combined treatment with siBCL2 and Gemcitabine in vivo and lead to increased TUNEL positivity. In contrast, non-transformed human foreskin fibroblasts showed only minor responses to this treatment. Our results demonstrate that siRNA-mediated silencing of anti-apoptotic bcl-2 enhances chemotherapy sensitivity in human pancreatic cancer cells in vitro and might lead to improved therapy responses in advanced stages of this disease. [source] Antitumor activity of a novel antisense oligonucleotide against Akt1JOURNAL OF CELLULAR BIOCHEMISTRY, Issue 4 2009Heejeong Yoon Abstract The AKT pathway is an important therapeutic target for cancer drug discovery as it functions as a main point for transducing extracellular and intracellular oncogenic signals. Moreover, alternations of the AKT pathway have been found in a wide range of cancers. In the present study, we found that an Akt1 antisense oligonucleotide (Akt1 AO) significantly downregulated the expression of AKT1 at both the mRNA and protein levels and inhibited cellular growth at nanomolar concentrations in various types of human cancer cells. Combined treatment of Akt1 AO with several cytotoxic drugs resulted in an additive growth inhibition of Caki-1 cells. The in vivo effectiveness of Akt1 AO was determined using two different xenograft nude mouse models. Akt1 AO (30,mg/kg, i.v. every 48,h) significantly inhibited the tumor growth of nude mouse subcutaneously implanted with U251 human glioblastoma cells after 27 days treatment. Akt1 AO (30,mg/kg, i.p continuously via osmotic pump) also significantly inhibited the tumor formation in nude mice implanted with luciferase-expressing MIA human pancreatic cancer cells (MIA-Luc) after 14 days of treatment. The luciferase signals from MIA-Luc cells were reduced or completely abolished after 2 weeks of treatment and the implanted tumors were barely detectable. Our findings suggest that Akt1 AO alone or in combination with other clinically approved anticancer agents should be further explored and progressed into clinical studies as a potential novel therapeutic agent. J. Cell. Biochem. 108: 832,838, 2009. © 2009 Wiley-Liss, Inc. [source] Suppression of growth of pancreatic cancer cell and expression of vascular endothelial growth factor by gene silencing with RNA interferenceJOURNAL OF DIGESTIVE DISEASES, Issue 4 2008Jian WANG OBJECTIVE: To explore the anti-angiogenesis and tumor cell growth suppressive effects resulted from gene silencing by RNAi in BxPC-3 human pancreatic cancer cells. METHODS: The designation and transfection of vascular endothelial growth factor (VEGF)-siRNA lentivirus was carried out in vitro. Real-time PCR and western blot were conducted to measure the expression levels of VEGF mRNA and protein. Flow cytometry was employed to evaluate cell apoptosis and cell death. A lactate dehydrogenase (LDH) assay was used to assess the cytotoxicity of VEGF-siRNA. A 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay was used to picture the cellular growth. For the in vivo study, BxPC-3 cells were injected subcutaneously into nude mice to form xenografts. The mice were divided into three groups according to the intervention used. The control group, the negative control group and the knockdown group of mice were injected with saline, an empty lentivirus vehicle and lentivirus carrying VEGF-siRNA, respectively. None of the mice died during the study. When these mice were killed, the xenografts were collected and the tumor sizes of the different groups were compared. Finally, immunohistochemistry was used to assess the VEGF expression level and microvascular density. RESULTS: After the transfection of VEGF-siRNA lentivirus, the cellular expression of VEGF mRNA decreased to 50% of the control and the VEGF protein in the BxPC-3 cells decreased to 30% of the control. Apoptosis and cell death increased after transfection of the VEGF-siRNA lentivirus. The LDH assay showed high cytotoxicity induced by VEGF-siRNA lentivirus transfection. The MTT assay showed slower cellular growth in the knockdown cells. Tumor growth suppression was observed in nude mice that had received the VEGF-siRNA lentivirus transfection, and the tumor sizes of the xenografts in this group were clearly smaller than those in other two groups. VEGF expression and microvascular density were significantly decreased. CONCLUSION: Vascular endothelial growth factor gene silencing via VEGF-siRNA can effectively inhibit the production of VEGF and exert an anti-angiogenesis and tumor cell growth suppressive effect both in vitro and in vivo. [source] Expression of intercellular adhesion molecule (ICAM)-1 or ICAM-2 is critical in determining sensitivity of pancreatic cancer cells to cytolysis by human ,,-T cells: Implications in the design of ,,-T-cell-based immunotherapies for pancreatic cancerJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 5 2009Zhiyong Liu Abstract Background and Aims:, ,,-T cells can recognize and kill malignant cells, particularly those of epithelial origin, through mechanisms which do not require the recognition of tumor-specific antigens (innate immune response). This natural ability of ,,-T cells to kill tumor cells in a tumor antigen-independent manner provides a strong rationale for developing clinical trials designed to exploit the innate antitumor properties of ,,-T cells. Methods:,In vitro studies were carried out to asses the sensitivity of pancreatic cancer cells (MIA PaCa2, BxPC-3, PANC-1) to killing by ex vivo expanded human ,,-T cells. Results:, The capacity of ,,-T cells to bind to as well as to kill pancreatic cancer cells correlated with the degree of surface expression of key intercellular adhesion molecules (ICAM) present on pancreatic cancer cells. Moreover, pancreatic cancer cells expressing neither ICAM-1 nor ICAM-2 were bound poorly by ,,-T cells and were found to be resistant to ,,-T-cell killing. However, upon transfection of resistant cells with ICAM-1 or ICAM-2, ,,-T cells were then able to bind to and subsequently kill these cells. Conclusion:,In vitro, the expression of ICAM-1 or ICAM-2 on human pancreatic cancer cells is critically important in determining the extent to which these cells are sensitive to killing by human ,,-T cells. Accordingly, in ongoing and future clinical studies using ,,-T cells for the treatment of a variety of epithelial-derived solid tumors,including pancreatic cancer,interventions intended to modulate ICAM expression on tumor cells may become important adjuncts to ,,-T-cell-based immunotherapies. [source] Synthesis and in-vitro antitumour activity of new naphthyridine derivatives on human pancreatic cancer cellsJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 8 2009Irene Banti Abstract Objectives The aim of the study was to evaluate the antitumour effect in vitro of newly synthesized 7-substituted 2,3-dihydro-1,8-naphthyridines. Methods Characterization tools included cell viability assay, caspase 3/7 induction, DNA fragmentation, fibroblast growth factor type 1 receptor kinase inhibition, and in-vitro antiangiogenic analysis. Key findings Treatment of MIA PaCa-2 human pancreatic cancer cells with test compounds showed time- and concentration-dependent cytotoxicity with IC50 values in the micromolar range. Compounds with an aminoalkyl or a diaminoalkyl side chain at the 7-position exhibited remarkable cytotoxicity, whereas the presence of a methyl group or a cyclic amine in the same position led to a significant decrease in their biological activity. Cytotoxicity screening demonstrated that the most active was compound 11 (mean 50% inhibition of cell proliferation (IC50) 11 ,M). This compound had an in-vitro antitumour efficacy superior to 5-fluorouracil (the lowest cell viability value after treatment (Emax) 0.2% and 19%, respectively) and proved to be less toxic than 5-fluorouracil against non-cancerous human oral epithelial cells. In addition, compound 11 induced apoptosis in MIA PaCa-2 cells and it was able to promote antiangiogenic effects in vitro. Finally, its cytotoxicity was enhanced in pancreatic cancer cells stimulated with fibroblast growth factor, while no substantial effect was observed on human bronchial smooth muscle cells stimulated with the same growth factor. Conclusions These findings suggest that 1,8-naphthyridine derivatives are a promising class of compounds in cancer research. In particular, the antitumour activity of compound 11 is worth further investigation. [source] Cyclophilin A is overexpressed in human pancreatic cancer cells and stimulates cell proliferation through CD147CANCER, Issue 10 2006Min Li Ph.D. Abstract BACKGROUND Although overexpression of cyclophilin A (CypA) is associated with several types of cancer, its role in pancreatic cancer has not been studied. In this study the expression of CypA and its receptor CD147 on pancreatic cancer was determined as well as the effect of exogenous CypA on pancreatic cancer cell proliferation. METHODS The expression of CypA and CD147 in human pancreatic cancer cell lines and tissues was determined with real-time reverse transcriptase polymerase chain reaction (RT-PCR), Western blot, and immunostaining. Cell proliferation in response to CypA was performed by [3H]thymidine incorporation assay. Phosphorylation of MAPK and cytokine secretion profiles in pancreatic cancer cells were determined by using the Bio-Plex phosphoprotein assay and cytokine assay. RESULTS Pancreatic cancer cell lines expressed significantly higher levels of CypA and CD147 than normal human pancreatic ductal epithelium (HPDE) cells. Expression of CypA and CD147 was also substantially higher in human pancreatic adenocarcinoma tissues than those in normal pancreatic tissues. Addition of exogenous CypA significantly stimulated pancreatic cancer cell proliferation in a dose-dependent manner and this effect was effectively blocked by pretreatment with anti-CD147 antibody. In addition, CypA activated ERK1/2 and p38 MAPK signaling pathways and increased the secretion of 2 key cytokines IL-5 and IL-17 in Panc-1 cells. CONCLUSIONS The expression of CypA and CD147 was significantly increased in both pancreatic cancer cell lines and tissues. Exogenous CypA promotes pancreatic cancer cell growth, which may be mediated through the interaction with CD147 and the activation of ERK1/2 and p38 MAPKs. Cancer 2006. © 2006 American Cancer Society. [source] Sonic hedgehog derived from human pancreatic cancer cells augments angiogenic function of endothelial progenitor cellsCANCER SCIENCE, Issue 6 2008Madoka Yamazaki Hedgehog signaling is important in the pathogenesis of pancreatic cancer. Several recent observations suggest the involvement of sonic hedgehog (SHH) in postnatal neovascularization. We identified a novel role for SHH in tumor-associated angiogenesis in pancreatic cancer. Immunohistochemical analysis revealed that patched homolog 1 (PTCH1), both a receptor for and transcriptional target of hedgehog signaling, was expressed in a small fraction of endothelial cells within pancreatic cancer, but not in normal pancreatic tissue. When endothelial progenitor cells (EPC) isolated from human peripheral blood were cultured with supernatant from SHH-transfected 293 cells or pancreatic cancer cells, mRNA levels of vascular endothelial growth factor (VEGF), stromal cell-derived factor-1 and angiopoietin-1 were significantly increased, whereas no such induction was observed in human umbilical vein endothelial cell (HUVEC) and human dermal microvascular endothelial cell (HMVEC). HUVEC tube formation was stimulated when cocultured with EPC, and preconditioning EPC with supernatant from KP-1 N pancreatic cancer cells highly expressing SHH significantly enhanced the effect. The effect was partially attenuated by specific inhibition of SHH with cyclopamine or a neutralizing antibody. These findings suggest that tumor-derived SHH can induce angiogenesis, and this is mediated by its effects on EPC specifically. Targeting SHH would be a novel therapeutic approach that can inhibit not only proliferation of cancer cells but also EPC-mediated angiogenesis. (Cancer Sci 2008; 99: 1131,1138) [source] Local interferon-, gene therapy elicits systemic immunity in a syngeneic pancreatic cancer model in hamsterCANCER SCIENCE, Issue 3 2007Hidehiko Hara The interferon (IFN) protein is a cytokine with pleiotropic biological functions that include induction of apoptosis, inhibition of angiogenesis and immunomodulation. We previously examined the two antitumor mechanisms, taking advantage of the fact that IFN-, did not show cross-species activity in its in vivo effect. In a nude mouse subcutaneous xenograft model using human pancreatic cancer cells, the expression of human IFN-, effectively induced cell death of human pancreatic cancer cells, whereas mouse IFN-, augmented antitumor immunity by stimulation of natural killer cells. Here, we extended our investigation to a syngeneic pancreatic cancer model, so that the integrated antitumor activity of local IFN-, gene therapy, including the antiproliferative, proapoptotic, antiangiogeneic and immunomodulatory effects, can be evaluated rigorously. When a recombinant hamster IFN-, adenovirus was injected into syngeneic subcutaneous tumors of hamster pancreatic cancer (PGHAM-1) cells in Syrian hamster, tumor growth was significantly suppressed due to cell death and T cell- and natural killer cell-mediated antitumor immunity. Moreover, in this case, tumor regression was observed not only for the injected subcutaneous tumors but also for the untreated tumors both in the peritoneal cavity and at distant sites. No significant systemic toxicity was observed in the treated hamsters. Moreover, the subcutaneous rechallenge of PGHAM-1 cells was rejected in three of four cured hamsters from the initial tumor challenge. This study further demonstrated that local IFN-, gene therapy is a promising therapeutic strategy for pancreatic cancer, due to its multiple mechanisms of antitumor activity and its lack of significant toxicity. (Cancer Sci 2007; 98: 455,463)) [source] | ||||||||||