125 research outputs found
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Endogenous VEGF isoform expression regulates tumour cell motility
Background: Vascular endothelial growth factor-A (VEGF) is produced by most cancer cells as multiple alternatively spliced isoforms, which display distinct receptor and matrix binding characteristics. In addition to being a major inducer of tumour angiogenesis, VEGF also has complex functions in angiogenesis-independent aspects of tumour growth,but the role of individual VEGF isoforms remains poorly understood. Here we investigated the effects of endogenous VEGF isoform expression on tumour cell migration and invasion.
Method: We used a panel of mouse fibrosarcoma cells we developed (fs188, fs164 and fs120) that express single VEGF isoforms (188, 164 or 120 respectively), under endogenous promoter control. We investigated adhesion to different matrices, 2D migration and invasion through 3D collagen.
Results: Fs188 cells, are typically mesenchymal, form ruffles, display strong integrin-dependent adhesion and express high levels of pERK1/2 and pAKT. In contrast, fs164 and fs120 cells are not typically mesenchymal in morphology; they display weak binding to collagen, lack ruffles and align longitudinally forming long multicellular chains and abundant cell-cell contacts. On 3D collagen, fs188 cells remain mesenchymal while fs164 and fs120 cells adopt a rounded/amoeboid and a mix of rounded/mesenchymal morphologies respectively. Cell morphology and migration are dependent on the cytoskeleton and actinomyosin contractility, to provide traction force in mesenchymal movement, and cortical contraction for rounded amoeboid motility. Consistent with their mesenchymal characteristics, fs188 cells migrated faster in 2D and invaded 3D collagen more efficiently than fs164 or fs120 cells. Contractility inhibitors caused fs164/fs120 cells to switch to a mesenchymal morphology and accelerated their migration but not that of fs188 cells.
Conclusion: VEGF isoforms are emerging as potential biomarkers for anti-VEGF therapies. Our results suggest that individual VEGF isoforms influence the migration and invasion strategies of tumour cells thus adding to the complexity of VEGF signaling within the tumor microenvironment. Acknowledgements This work was funded by Cancer Research UK
Development of clinically relevant in vivo metastasis models using human bone discs and breast cancer patient-derived xenografts
Background
Late-stage breast cancer preferentially metastasises to bone; despite advances in targeted therapies, this condition remains incurable. The lack of clinically relevant models for studying breast cancer metastasis to a human bone microenvironment has stunted the development of effective treatments for this condition. To address this problem, we have developed humanised mouse models in which breast cancer patient-derived xenografts (PDXs) metastasise to human bone implants with low variability and high frequency.
Methods
To model the human bone environment, bone discs from femoral heads of patients undergoing hip replacement surgery were implanted subcutaneously into NOD/SCID mice. For metastasis studies, 7 patient-derived xenograft tumours (PDX: BB3RC32, ER+ PR+ HER2−; BB2RC08, ER+ PR+ ER2−; BB6RC37, ER− PR− HER2− and BB6RC39, ER+ PR+ HER2+), MDA-MB-231-luc2, T47D-luc2 or MCF7-Luc2 cells were injected into the 4th mammary ducts and metastases monitored by luciferase imaging and confirmed on histological sections. Bone integrity, viability and vascularisation were assessed by uCT, calcein uptake and histomorphometry. Expression profiling of genes/proteins during different stages of metastasis were assessed by whole genome Affymetrix array, real-time PCR and immunohistochemistry. Importance of IL-1 was confirmed following anakinra treatment.
Results
Implantation of femoral bone provided a metabolically active, human-specific site for tumour cells to metastasise to. After 4 weeks, bone implants were re-vascularised and demonstrated active bone remodelling (as evidenced by the presence of osteoclasts, osteoblasts and calcein uptake). Restricting bone implants to the use of subchondral bone and introduction of cancer cells via intraductal injection maximised metastasis to human bone implants. MDA-MB-231 cells specifically metastasised to human bone (70% metastases) whereas T47D, MCF7, BB3RC32, BB2RC08, and BB6RC37 cells metastasised to both human bone and mouse bones. Importantly, human bone was the preferred metastatic site especially from ER+ PDX (100% metastasis human bone compared with 20–75% to mouse bone), whereas ER-ve PDX developed metastases in 20% of human and 20% of mouse bone. Breast cancer cells underwent a series of molecular changes as they progressed from primary tumours to bone metastasis including altered expression of IL-1B, IL-1R1, S100A4, CTSK, SPP1 and RANK. Inhibiting IL-1B signalling significantly reduced bone metastasis.
Conclusions
Our reliable and clinically relevant humanised mouse models provide significant advancements in modelling of breast cancer bone metastasis
Family systems and mental health issues: A resilience approach
In many cases the consumers of mental health information and support are the families of mental health sufferers. The aim of the project was to understand resilience in people who live with or support a family member with a diagnosed or undiagnosed mental illness. Participants were 15 carers (one male, 14 female). Semi-structured interviews were transcribed and analysed using content analysis. Eight recurring themes emerged which indicated the challenges the carers faced and provided indications of the positive and negative personal, family and social factors that impacted on their lives. These themes were \u27Getting to CLAN WA\u27, \u27Accessing help including CLAN WA\u27, \u27Impact of living with a person who has a mental illness or problematic behaviour\u27, \u27Family and cultural issues\u27, \u27Communication within the family\u27,\u27Coping strategies and evidence of resilience\u27, \u27Social support\u27 and \u27Notion of sacrifice\u27. There is still considerable work to do in supporting people who live with or support a family member in these circumstances. The findings demonstrate that individuals living with adversity can do more than just survive the proces
Novel methods of targeting IL-1 signalling for the treatment of breast cancer bone metastasis
Breast cancer bone metastasis is currently incurable. Evidence suggests that inhibiting IL-1 signalling with the IL1R antagonist, Anakinra, or the IL1β antibody, Canakinumab, prevents metastasis and almost eliminates breast cancer growth in the bone. However, these drugs increase primary tumour growth. We, therefore, investigated whether targeting other members of the IL-1 pathway (Caspase-1, IL1β or IRAK1) could reduce bone metastases without increasing tumour growth outside of the bone. Inhibition of IL-1 via MLX01 (IL1β secretion inhibitor), VRT043198/VX765 (Caspase-1 inhibitor), Pacritinib (IRAK1 inhibitor) or Anakinra (IL1R antagonist) on tumour cell viability, migration and invasion were assessed in mouse mammary E0771 and Py8119 cells in vitro and on primary tumour growth, spontaneous metastasis and metastatic outgrowth in vivo. In vitro, Inhibition of IL-1 signalling by MLX01, VRT043198 and Anakinra reduced migration of E0771 and Py8119 cells and reversed tumour-derived IL1β induced-increased invasion and migration towards bone cells. In vivo, VX765 and Anakinra significantly reduced spontaneous metastasis and metastatic outgrowth in the bone, whereas MLX01 reduced primary tumour growth and bone metastasis. Pacritinib had no effect on metastasis in vitro or in vivo. Targeting IL-1 signalling with small molecule inhibitors may provide a new therapeutic strategy for breast cancer bone metastasis
Search based software engineering: Trends, techniques and applications
© ACM, 2012. This is the author's version of the work. It is posted here by permission of ACM for your personal use. Not for redistribution. The definitive version is available from the link below.In the past five years there has been a dramatic increase in work on Search-Based Software Engineering (SBSE), an approach to Software Engineering (SE) in which Search-Based Optimization (SBO) algorithms are used to address problems in SE. SBSE has been applied to problems throughout the SE lifecycle, from requirements and project planning to maintenance and reengineering. The approach is attractive because it offers a suite of adaptive automated and semiautomated solutions in situations typified by large complex problem spaces with multiple competing and conflicting objectives.
This article provides a review and classification of literature on SBSE. The work identifies research trends and relationships between the techniques applied and the applications to which they have been applied and highlights gaps in the literature and avenues for further research.EPSRC and E
Endogenous production of IL-1B by breast cancer cells drives metastasis and colonisation of the bone microenvironment
Background: Breast cancer bone metastases are incurable highlighting the need for new therapeutic targets. After colonizing bone, breast cancer cells remain dormant, until signals from the microenvironment stimulate outgrowth into overt metastases. Here we show that endogenous production of IL-1B by tumor cells drives metastasis and growth in bone. Methods: Tumor/stromal IL-B and IL-1R1 expression was assessed in patient samples and effects of the IL-1R antagonist, Anakinra or the IL-1B antibody Canakinumab on tumor growth and spontaneous metastasis were measured in a humanized mouse model of breast cancer bone metastasis. Effects of tumor cell-derived IL-1B on bone colonisation and parameters associated with metastasis were measured in MDA-MB-231, MCF7 and T47D cells transfected with IL-1B/control. Results: In tissue samples from >1300 patients with stage II/III breast cancer, IL-1B in tumor cells correlated with relapse in bone (hazard ratio 1.85; 95% CI 1.05-3.26; P=0.02) and other sites (hazard ratio 2.09; 95% CI 1.26-3.48; P=0.0016). In a humanized model of spontaneous breast cancer metastasis to bone, Anakinra or Canakinumab reduced metastasis and reduced the number of tumor cells shed into the circulation. Production of IL-1B by tumor cells promoted EMT (altered E-Cadherin, N-Cadherin and G-Catenin), invasion, migration and bone colonisation. Contact between tumor and osteoblasts or bone marrow cells increased IL-1B secretion from all three cell types. IL-1B alone did not stimulate tumor cell proliferation. Instead, IL-1B caused expansion of the bone metastatic niche leading to tumor proliferation. Conclusion: Pharmacological inhibition of IL-1B has potential as a novel treatment for breast cancer metastasis
The stigma of mental illness in Southern Ghana: attitudes of the urban population and patients’ views
PURPOSE: Stigma is a frequent accompaniment of mental illness leading to a number of detrimental consequences. Most research into the stigma connected to mental illness was conducted in the developed world. So far, few data exist on countries in sub-Saharan Africa and no data have been published on population attitudes towards mental illness in Ghana. Even less is known about the stigma actually perceived by the mentally ill persons themselves. METHOD: A convenience sample of 403 participants (210 men, mean age 32.4 ± 12.3 years) from urban regions in Accra, Cape Coast and Pantang filled in the Community Attitudes towards the Mentally Ill (CAMI) questionnaire. In addition, 105 patients (75 men, mean age 35.9 ± 11.0 years) of Ghana's three psychiatric hospitals (Accra Psychiatry Hospital, Ankaful Hospital, Pantang Hospital) answered the Perceived Stigma and Discrimination Scale. RESULTS: High levels of stigma prevailed in the population as shown by high proportions of assent to items expressing authoritarian and socially restrictive views, coexisting with agreement with more benevolent attitudes. A higher level of education was associated with more positive attitudes on all subscales (Authoritarianism, Social Restrictiveness, Benevolence and Acceptance of Community Based Mental Health Services). The patients reported a high degree of experienced stigma with secrecy concerning the illness as a widespread coping strategy. Perceived stigma was not associated with sex or age. DISCUSSION: The extent of stigmatising attitudes within the urban population of Southern Ghana is in line with the scant research in other countries in sub-Saharan Africa and mirrored by the experienced stigma reported by the patients. These results have to be seen in the context of the extreme scarcity of resources within the Ghanaian psychiatric system. Anti-stigma efforts should include interventions for mentally ill persons themselves and not exclusively focus on public attitudes
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