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1.

Background  

Desmoid tumour is a benign, non metastasising neoplasm characterised by an elevated deposition of organic macromolecules in the extracellular matrix (ECM). The matrix metalloproteinases (MMPs) are a family of zinc-dependent proteinases involved in the degradation of ECM macromolecules. The MMPs and their natural inhibitors (TIMPs) have been implicated in tumour growth, invasion and metastasis. In this study we provide evidence that the in vitro cultured cell line from desmoid tumour accumulates more collagen fibres in the ECM than healthy fibroblasts.  相似文献   

2.

Background:

Insulin-like growth factors (IGF-I and IGF-II) signal via the type 1 IGF receptor (IGF-1R) and IGF-II also activates the insulin receptor isoform A (IR-A). Signalling via both receptors promotes tumour growth, survival and metastasis. In some instances IGF-II action via the IR-A also promotes resistance to anti-IGF-1R inhibitors. This study assessed the efficacy of two novel modified IGF-binding protein-2 (IGFBP-2) proteins that were designed to sequester both IGFs. The two modified IGFBP-2 proteins were either protease resistant alone or also lacked the ability to bind extracellular matrix (ECM).

Methods:

The modified IGFBP-2 proteins were tested in vitro for their abilities to inhibit cancer cell proliferation and in vivo to inhibit MCF-7 breast tumour xenograft growth.

Results:

Both mutants retained low nanomolar affinity for IGF-I and IGF-II (0.8–2.1-fold lower than IGFBP-2) and inhibited cancer cell proliferation in vitro. However, the combined protease resistant, non-matrix-binding mutant was more effective in inhibiting MCF-7 tumour xenograft growth and led to inhibition of angiogenesis.

Conclusions:

By removing protease cleavage and matrix-binding sites, modified IGFBP-2 was effective in inhibiting tumour growth and reducing tumour angiogenesis.  相似文献   

3.

Background:

Neuropilin-1 (NRP1) is a non-tyrosine kinase receptor for vascular endothelial growth factor (VEGF) recently implicated in tumour functions.

Methods:

In this study we used a specific antagonist of VEGF binding to the NRP1 b1 domain, EG3287, to investigate the functional roles of NRP1 in human carcinoma cell lines, non-small-cell lung A549, kidney ACHN, and prostate DU145 cells expressing NRP1, and the underlying mechanisms involved.

Results:

EG3287 potently displaced the specific binding of VEGF to NRP1 in carcinoma cell lines and significantly inhibited the migration of A549 and ACHN cells. Neuropilin-1 downregulation by siRNA also decreased cell migration. EG3287 reduced the adhesion of A549 and ACHN cells to extracellular matrix (ECM), and enhanced the anti-adhesive effects of a β1-integrin function-blocking antibody. EG3287 increased the cytotoxic effects of the chemotherapeutic agents 5-FU, paclitaxel, or cisplatin on A549 and DU145 cells, through inhibition of integrin-dependent cell interaction with the ECM.

Conclusions:

These findings indicate that NRP1 is important for tumour cell migration and adhesion, and that NRP1 antagonism enhances chemosensitivity, at least in part, by interfering with integrin-dependent survival pathways. A major implication of this study is that therapeutic strategies targeting NRP1 in tumour cells may be particularly useful in combination with other drugs for combating tumour survival, growth, and metastatic spread independently of an antiangiogenic effect of blocking NRP1.  相似文献   

4.

Backround:

Testicular germ cell tumour (TGCT) is the most common cause of death from solid tumours in young men and especially for platinum-refractory patients novel treatment approaches are urgently needed. Using an in silico screening approach for the detection of novel cancer drugs with inhibitory effects on the tyrosine kinase activity of growth factors (e.g., VEGFR, PDGFR), we identified two compounds (HP-2 and HP-14) with antiangiogenic and antiproliferative potency, which were evaluated in endothelial cell models and TGCT cells.

Results:

HP-2 and HP-14 effectively inhibited the growth of VEGFR-2-expressing TGCT cell lines (Tera-1, Tera-2 and 2102EP) and endothelial cell models, while they failed to supress the growth of VEGFR-2-lacking tumour cells. cDNA-microarrays revealed an inhibition of the expression of several growth factor receptors and related signal transduction molecules. Vascular endothelial growth factor (VEGF)-induced cell migration was also potently inhibited. Cell cycle-regulating proteins such as p21 and p27 were upregulated, leading to an S-phase arrest. Additional in vivo evaluations confirmed the antiangiogenic potency and good tolerability of the novel substances.

Conclusion:

Our data show that the identified novel compounds inhibit the growth of TGCT cells and decrease angiogenic microvessel formation. The mode of action involves cell cycle arresting effects and changes in the expression pattern of several angiogenic genes. The novel compounds may qualify as new candidates for targeted treatment of TGCT and merit further evaluation.  相似文献   

5.

Introduction  

There is increasing recognition of the role of the microenvironment in the control of both normal and tumour cell behaviour. In the breast, myoepithelial cells and fibroblasts can influence tumour cell behaviour, with myoepithelial cells exhibiting a broad tumour-suppressor activity while fibroblasts frequently promote tumour growth and invasion. This study describes the development of physiologically relevant three-dimensional heterotypic culture systems containing mixed normal or tumour-derived breast populations and shows how such models can be used to dissect the interactions that influence cell behaviour.  相似文献   

6.

Purpose

Some members of a novel series of pyrrolo-1,5-benzoxazepines (PBOXs) are microtubule-targeting agents capable of inducing apoptosis in a variety of human cancerous cells, hence, they are currently being developed as potential anti-cancer agents. The purpose of this study was to first characterise the activities of a novel PBOX analogue, PBOX-16 and then investigate the anti-angiogenic potential of both PBOX-16 and its prototype PBOX-6.

Methods

The effects of PBOX-6 and -16 on cancerous cells (chronic myeloid leukaemia K562 cells and ovarian carcinoma A2780 cells) and primary cultured human umbilical vein endothelial cells (HUVECs) were examined by assessing cell proliferation, microtubular organisation, DNA analysis of cell cycle progression and caspase-3/7 activity. Their anti-angiogenic properties were then investigated by examining their ability to interfere with HUVEC differentiation into capillary-like structures and vascular endothelial growth factor (VEGF)-stimulated HUVEC migration.

Results

PBOX-6 and -16 inhibited proliferation of K562, A2780 and HUVEC cells in a concentration-dependent manner. PBOX-16, confirmed as a novel depolymerising agent, was approximately tenfold more potent than PBOX-6. Inhibition of cell proliferation was mediated by G2/M arrest followed by varying degrees of apoptosis depending on the cell type; endothelial cells underwent less apoptosis than either of the cancer cell lines. In addition to the anti-tumourigenic properties, we also describe a novel anti-angiogenic function for PBOXs: treatment with PBOXs inhibited the spontaneous differentiation of HUVECs into capillary-like structures when grown on a basement membrane matrix preparation (Matrigel?) and also significantly reduced VEGF-stimulated HUVEC migration.

Conclusion

Dual targeting of both the tumour cells and the host endothelial cells by PBOX compounds might enhance the anti-cancer efficacy of these drugs.  相似文献   

7.

Background

Many factors influence breast cancer progression, including the ability of progenitor cells to sustain or increase net tumour cell numbers. Our aim was to define whether alterations in putative progenitor populations could predict clinicopathological factors of prognostic importance for cancer progression.

Methods

Primary cultures were established from human breast tumour and adjacent non-tumour tissue. Putative progenitor cell populations were isolated based on co-expression or concomitant absence of the epithelial and myoepithelial markers EPCAM and CALLA respectively.

Results

Significant reductions in cellular senescence were observed in tumour versus non-tumour cultures, accompanied by a stepwise increase in proliferation:senescence ratios. A novel correlation between tumour aggressiveness and an imbalance of putative progenitor subpopulations was also observed. Specifically, an increased double-negative (DN) to double-positive (DP) ratio distinguished aggressive tumours of high grade, estrogen receptor-negativity or HER2-positivity. The DN:DP ratio was also higher in malignant MDA-MB-231 cells relative to non-tumourogenic MCF-10A cells. Ultrastructural analysis of the DN subpopulation in an invasive tumour culture revealed enrichment in lipofuscin bodies, markers of ageing or senescent cells.

Conclusions

Our results suggest that an imbalance in tumour progenitor subpopulations imbalances the functional relationship between proliferation and senescence, creating a microenvironment favouring tumour progression.  相似文献   

8.

Background:

The influence of human prolactin (hPRL) on the development of breast and other types of cancer is well established. Little information, however, exists on the effects of hPRL on squamous cell carcinomas of the head and neck (SCCHNs).

Methods:

In this study, we evaluated prolactin receptor (PRLR) expression in SCCHN cell lines and assessed by immunohistochemistry the expression in 89 patients with SCCHNs. The PRLR expression was correlated with clinicopathological characteristics as well as clinical outcome. The effect of hPRL treatment on tumour cell growth was evaluated in vitro.

Results:

Immunoreactivity for PRLR was observed in 85 out of 89 (95%) tumours. Multivariate COX regression analysis confirmed high levels of PRLR expression (>25% of tumour cells) to be an independent prognostic factor with respect to overall survival (HR=3.70, 95% CI: 1.14–12.01; P=0.029) and disease-free survival (P=0.017). Growth of PRLR-positive cancer cells increased in response to hPRL treatment.

Conclusion:

Our data indicate that hPRL is an important growth factor for SCCHN. Because of PRLR expression in a vast majority of tumour specimens and its negative impact on overall survival, the receptor represents a novel prognosticator and a promising drug target for patients with SCCHNs.  相似文献   

9.
10.

Background:

Prokineticin-1 (PROK1) and prokineticin-2 (PROK2) are chemokine-like proteins that may influence cancer growth by regulating host defence and angiogenesis. Their significance in viral infection-associated cancer is incompletely understood. We studied prokineticins in Merkel cell carcinoma (MCC), a skin cancer linked with Merkel cell polyomavirus (MCPyV) infection.

Methods:

Carcinoma cell expression of PROK1 and PROK2 and their receptors (PROKR1 and PROKR2) was investigated with immunohistochemistry, and tumour PROK1 and PROK2 mRNA content with quantitative PCR from 98 MCCs. Subsets of tumour infiltrating leukocytes were identified using immunohistochemistry.

Results:

Merkel cell polyomavirus-positive MCCs had higher than the median PROK2 mRNA content, whereas MCPyV-negative MCCs contained frequently PROK1 mRNA. Cancers with high tumour PROK2 mRNA content had high counts of tumour infiltrating macrophages (CD68+ and CD163+ cells). Patients with higher than the median PROK2 mRNA content had 44.9% 5-year survival compared with 23.5% among those with a smaller content (hazard ratio (HR): 0.53; 95% confidence interval (CI): 0.34–0.84; P=0.005), whereas the presence of PROK1 mRNA in tumour was associated with unfavourable survival (P=0.052).

Conclusions:

The results suggest that prokineticins are associated with MCPyV infection and participate in regulation of the immune response in MCC, and may influence outcome of MCC patients.  相似文献   

11.

Background:

PG545 is a heparan sulfate (HS) mimetic that inhibits tumour angiogenesis by sequestering angiogenic growth factors in the extracellular matrix (ECM), thus limiting subsequent binding to receptors. Importantly, PG545 also inhibits heparanase, the only endoglycosidase which cleaves HS chains in the ECM. The aim of the study was to assess PG545 in various solid tumour and metastasis models.

Methods:

The anti-angiogenic, anti-tumour and anti-metastatic properties of PG545 were assessed using in vivo angiogenesis, solid tumour and metastasis models. Pharmacokinetic (PK) data were also generated in tumour-bearing mice to gain an understanding of optimal dosing schedules and regimens.

Results:

PG545 was shown to inhibit angiogenesis in vivo and induce anti-tumour or anti-metastatic effects in murine models of breast, prostate, liver, lung, colon, head and neck cancers and melanoma. Enhanced anti-tumour activity was also noted when used in combination with sorafenib in a liver cancer model. PK data revealed that the half-life of PG545 was relatively long, with pharmacologically relevant concentrations of radiolabeled PG545 observed in liver tumours.

Conclusion:

PG545 is a new anti-angiogenic clinical candidate for cancer therapy. The anti-metastatic property of PG545, likely due to the inhibition of heparanase, may prove to be a critical attribute as the compound enters phase I clinical trials.  相似文献   

12.

Purpose

Tumor protein D54 (TPD54) belongs to the TPD52 family of proteins and is expressed in several types of cancer, including oral squamous cell carcinoma (OSCC). Here, we investigated relationships between various OSCC-related characteristics and TPD54 expression in vitro.

Methods

The expression of TPD54 in several OSCC-derived cell lines and normal, non-malignant, cells was assessed. Based on the results obtained, OSCC-derived SAS cells were subsequently subjected to exogenous over-expression of alternative splice variants (ASVs) of TPD54 and to TPD54 knock-down, mediated by siRNA. Next, the role of TPD54 in cellular growth, apoptosis, invasion, migration and extracellular-matrix (ECM)-dependent migration and attachment was investigated, as also the concomitant expression of integrins and integrin-related proteins by the OSCC-derived cells.

Results

Western blot analysis and RT-PCR revealed that several TPD54 ASVs were expressed in the OSCC-derived cell lines tested. Neither exogenous ASV over-expression nor TPD54 knock-down modulated the proliferation or invasion of SAS cells in a monolayer culture assay. However, exogenous ASV over-expression did decrease anchorage-independent growth and TPD54 knock-down did increase anchorage-independent growth, irrespective of caspase activities. The same effects were observed on ECM-dependent cellular migration and cell attachment to the ECM. The expression levels of the major α and β integrin subunits, and of E-cadherin, were found to be similar to those observed in the non-transfected control cells, whereas talin1 expression was found to be increased after TPD54 knock-down. Also Akt was found to be activated after TPD54 knock-down, even in the absence of serum stimulation. Very similar effects were observed in the OSCC-derived cell lines HSC 2 and HSC 3.

Conclusions

Our results show that TPD54 affects OSCC cell attachment to the ECM, OSCC cell migration, and Akt/PKB activation by modulating integrin activation via a talin1-mediated inside-out signal of the ECM. Based on these results, we suggest that TPD54 may serve as a novel biomarker for OSCC and as a putative target for OSCC therapy.  相似文献   

13.

Background

The simultaneous detection of protein expression and gene copy number changes in patient samples, like paraffin-embedded tissue sections, is challenging since the procedures of immunohistochemistry (IHC) and Fluorescence in situ Hybridization (FISH) negatively influence each other which often results in suboptimal staining. Therefore, we developed a novel automated algorithm based on relocation which allows subsequent detection of protein content and gene copy number changes within the same cell.

Methods

Paraffin-embedded tissue sections of colorectal cancers were stained for CD133 expression. IHC images were acquired and image coordinates recorded. Slides were subsequently hybridized with fluorescently labeled DNA probes. FISH images were taken at the previously recorded positions allowing for direct comparison of protein expression and gene copy number signals within the same cells/tissue areas. Relocation, acquisition of the IHC and FISH images, and enumeration of FISH signals in the immunophenotyped tumour areas were done in an automated fashion.

Results

Automated FISH analysis was performed on 13 different colon cancer samples that had been stained for CD133; each sample was scored for MYC, ZNF217 and Chromosome 6 in CD133 positive and negative glands. From the 13 cases four (31%) showed amplification for the MYC oncogene and seven of 13 (54%) cases were amplified for ZNF217. There was no significant difference between CD133 positive tumour and CD133 negative tumour cells.

Conclusion

The technique and algorithm presented here enables an easy and reproducible combination of IHC and FISH based on a novel automated algorithm using relocation and automated spot counting.  相似文献   

14.

Purpose

To examine the in vitro anticancer activity of Melaleuca alternifolia (tea tree) oil (TTO), and its major active terpene component, terpinen-4-ol, against two aggressive murine tumour cell lines, AE17 mesothelioma and B16 melanoma.

Methods

Effects of TTO and terpinen-4-ol on the cellular viability of two tumour cell lines and fibroblast cells were assessed by MTT assay. Induction of apoptotic and necrotic cell death was visualised by fluorescent microscopy and quantified by flow cytometry. Tumour cell ultrastructural changes were examined by transmission electron microscopy and changes in cell cycle distribution were assessed by flow cytometry, with changes in cellular morphology monitored by video time lapse microscopy.

Results

TTO and terpinen-4-ol significantly inhibited the growth of two murine tumour cell lines in a dose- and time-dependent manner. Interestingly, cytotoxic doses of TTO and terpinen-4-ol were significantly less efficacious against non-tumour fibroblast cells. TTO and terpinen-4-ol induced necrotic cell death coupled with low level apoptotic cell death in both tumour cell lines. This primary necrosis was clarified by video time lapse microscopy and also by transmission electron microscopy which revealed ultrastructural features including cell and organelle swelling following treatment with TTO. In addition, both TTO and terpinen-4-ol induced their inhibitory effect by eliciting G1 cell cycle arrest.

Conclusion

TTO and terpinen-4-ol had significant anti-proliferative activity against two tumour cell lines. Moreover, the identification of primary necrotic cell death and cell cycle arrest of the aggressive tumour cells highlights the potential anticancer activity of TTO and terpinen-4-ol.  相似文献   

15.

Aims

This study aims to describe the incidence of infective complications, including tumour endoprosthesis infection, in a cohort of patients undergoing tumour endoprosthesis surgery in Victoria, Australia.

Methods

This retrospective cohort study was performed over 15 years (January 1996–December 2010).

Results

121 patients underwent tumour endoprosthesis surgery during the study period. Patients were followed for a median of 34 months (interquartile range [IQR] 17, 80). Overall, 34 patients (28%) experienced infective complications including: bacteraemia in 19 patients (16%) and tumour endoprosthesis infection in 17 (14%). The majority of patients with early and late acute infections (haematogenous) were managed with debridement and retention of the prosthesis in addition to biofilm-active antibiotics. Late chronic infections were predominantly managed by exchange of the prosthesis. The overall success rate of treatment was 71%. The success rate for debridement and retention was 75% compared with 67% for exchange procedures.

Conclusions

There is a significant rate of infective complications following tumour endoprosthesis surgery including 14% of patients experiencing infection involving the tumour endoprosthesis. This study is the first to report on outcomes from debridement and retention of the prosthesis; which had comparable success rates to other treatment modalities.  相似文献   

16.

Background:

Macrophage migration inhibitory factor (MIF) has been proposed as a link between inflammation and tumorigenesis. Despite its potentially broad influence in tumour biology and prevalent expression, the value of MIF as a therapeutic target in cancer remains unclear. We sought to validate MIF in tumour models by achieving a complete inhibition of its expression in tumour cells and in the tumour stroma.

Methods:

We used MIF shRNA-transduced B16-F10 melanoma cells implanted in wild-type and MIF−/− C57Bl6 mice to investigate the effect of loss of MIF on tumour growth. Cytokine detection and immunohistochemistry (IHC) were used to evaluate tumours ex vivo.

Results:

Macrophage migration inhibitory factor shRNA inhibited expression of MIF protein by B16-F10 melanoma cells in vitro and in vivo. In vitro, the loss of MIF in this cell line resulted in a decreased response to hypoxia as indicated by reduced expression of VEGF. In vivo the growth of B16-F10 tumours was inhibited by an average of 47% in the MIF−/− mice compared with wild-type but was unaffected by loss of MIF expression by the tumour cells. Immunohistochemistry analysis revealed that microvessel density was decreased in tumours implanted in the MIF−/− mice. Profiling of serum cytokines showed a decrease in pro-angiogenic cytokines in MIF−/− mice.

Conclusion:

We report that the absence of MIF in the host resulted in slower tumour growth, which was associated with reduced vascularity. While the major contribution of MIF appeared to be in the regulation of angiogenesis, tumour cell-derived MIF played a negligible role in this process.  相似文献   

17.

Background:

Head and neck cancers (HNC) are aggressive tumours. Overexpression of p16 in HNC correlates with human papilloma virus (HPV)-associated HNC that carry a better prognosis than HPV-negative tumours. Angiogenesis is an important factor in tumour progression. Our aim was to dissect the impact of p16 expression on angiogenesis factors in HNC.

Methods:

Eighteen newly diagnosed HNC patients and controls were analysed. Eleven pro- and anti-angiogenesis factors were quantified using multiplex ELISA in HNC patients and controls. Angiogenesis factors were analysed in tumour tissue using immunohistochemistry.

Results:

Circulating levels of endostatin (anti-angiogenesis factor) were higher in the HNC group compared with healthy donors. Interestingly, the pro-angiogenesis factors angiopoietin-1 and vascular endothelial growth factor (VEGF) were significantly higher in patients with p16-negative compared with p16-positive HNC. Moreover, the major source of VEGF in p16-positive HNC tissue was tumour stromal cells. In contrast, both tumour cells and stromal cells expressed VEGF in p16-negative tissue.

Conclusions:

We show that p16-negative tumours associate with increased circulating levels of pro-angiogenic VEGF and angiopoietin-1. Tissue expression of VEGF differs between p16-positive and p16-negative tumours. These findings may explain differences in the biological behaviour of p16-positive and p16-negative HNC. Better understanding of mechanisms by which the p16 status influences tumour angiogenesis may guide the development of targeted therapies.  相似文献   

18.
19.

Background:

Tumour cells and stromal cells interact in the tumour microenvironment; moreover, stromal cells can acquire abnormalities that contribute to tumour progression. However, interactions between lymphatic endothelial cells (LECs) and tumour cells are largely unexamined. In this study, we aimed to determine whether tumour-specific LECs inhabit the tumour microenvironment and examine their influence on this microenvironment.

Methods:

We isolated normal LECs (NLECs) from a non-metastatic lymph node and tumour-associated LECs (TLECs) from cancerous lymph nodes. We examined proliferative and migratory potency, growth factor production, and gene expression of each type of LEC. Moreover, we developed a co-culture system to investigate the interactions between gastric cancer cells and LECs.

Results:

When compared with NLEC, TLECs had an abnormal shape, high proliferative and migratory abilities, and elevated expression of genes associated with inflammation, cell growth, and cell migration. NLECs co-cultured with gastric cancer cells from the OCUM12 cell line acquired TLEC-like phenotypes. Also, OCUM12 cells co-cultured with TLECs expressed high levels of genes responsible for metastasis.

Conclusions:

Our results demonstrated that LECs interacted with tumour cells and obtained abnormal phenotypes that could have important roles in tumour progression.  相似文献   

20.

Background:

CD70 is an ideal target for antibody-based therapies because of its aberrant high expression in renal carcinomas and non-Hodgkin lymphomas and its highly restricted expression in normal tissues. The expression profiling of CD70 in carcinomas has been limited because of the lack of a CD70-specific reagent that works in formalin-fixed paraffin-embedded (FFPE) tissues.

Methods:

We generated murine monoclonal antibodies (mAbs) specific for CD70 and validated their specificity by western blot analysis and developed a protocol for immunohistochemistry on FFPE tissues. CD70+ tumour cell lines were used for testing the anti-tumour activity of the anti-CD70 antibody–drug conjugate, SGN-75.

Results:

We report novel detection of CD70 expression in multiple cancers including pancreatic (25%), larynx/pharynx (22%), melanoma (16%), ovarian (15%), lung (10%), and colon (9%). Our results show that pancreatic and ovarian tumour cell lines, which express high levels of endogenous or transfected CD70, are sensitive to the anti-tumour activity of SGN-75 in vitro and in vivo.

Conclusion:

Development of murine mAbs for robust and extensive screening of FFPE samples coupled with the detection of anti-tumour activity in novel indications provide rationale for expanding the application of SGN-75 for the treatment of multiple CD70 expressing cancers.  相似文献   

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