Integrated BioSciences PhD Studentship competition 2012

The role of inflammatory cytokines in the initiation of neuropathic pain and and functional regeneration after peripheral nerve repair

Peripheral nerve injuries are common; it is estimated that there are 300,000 peripheral nerve injuries per year in Europe (1/1000 population). These injuries result in loss of sensory and/or motor function, and some patients develop chronic neuropathic pain. The management of nerve injury induced pain (dysaesthesia) is unsatisfactory and new therapeutic methods based on a better understanding of the aetiology are needed. This study will investigate the peripheral and central mechanisms underlying injury-induced neuropathic pain, and will link the level of peripheral neural discharge following nerve injury to expression of peripheral and central inflammatory markers. This will help identify potential new therapeutic agents for the treatment of neuropathic pain.
For further details please contact Dr Simon Atkins (s.atkins@sheffield.ac.uk)

Developing tissue engineered mucosal models to investigate the role of tumour-associated macrophages in oral cancer progression.

Inflammation is a critical component of tumour progression and tumour-associated macrophages (TAM) represent a prominent component of the leukocytic infiltrate of many human tumours. There is evidence to show that TAM promotes a pro-tumour phenotype that exacerbates tumour growth, principally by secreting factors that promote angiogenesis. However, their role in oral cancer is poorly defined. The aim of this project is to develop a tissue engineered in vitro model of oral cancer in order to evaluate the role of TAM in cancer invasion and tumour progression. Macrophages will be introduced into a three dimensional model of oral cancer. The development of TAM and the phenotype of these cells (M1 vs M2) as well as their secreted products will be measured along with their effects on tumour cell invasion and proliferation. The effects of irradiation will also be examined to determine its effects on macrophage phenotype and secretome and whether these effects are host or tumour mediated.
For further details please contact Dr Craig Murdoch (c.murdoch@sheffield.ac.uk)

Understanding the functional role of Retinoic Acid Receptor β2 in
oral precancerous and cancerous lesions

As oral cancer incidence continues to rise, there is a need for a greater understanding of the early molecular events in preinvasive lesions. Loss of the retinoid receptor RARβ early in oral cancer development has been known for some time, but the consequences of this have not been studied in detail. Pinpointing the role of RARβ in the balance between differentiation and replicative senescence is key to using retinoids effectively as chemo-preventive agents. This project will investigate the functional consequences of derangements in RARβ signalling by manipulation of RARβ expression in a unique panel of oral precancer cell cultures and in also oral biopsy tissues, in an attempt to identify which patients may benefit from this therapy.
For further details please contact Dr Keith Hunter (k.hunter@sheffield.ac.uk)

Investigation of novel outer membrane sialic acid transport systems in anaerobic pathogens

Sialic acid is a key sugar in the human body, forming the terminal glycan moiety on many important human glycoproteins. Many pathogenic bacteria that inhabit the human niche have evolved the ability to utilise and target this sugar for nutrition and processing to coat their own surfaces.
Our group has identified a novel sialic acid transport system that is present in a range of human pathogens. The project will utilise a number of molecular and biochemical techniques aimed at understanding the mechanism and role of this transport system in biofilm formation and human cell interactions. The information gained will aid development of novel antimicrobial therapies and will be conducted in collaboration with the Department of Molecular Biology and Biotechnology.
For further details please contact Dr Graham Stafford (g.stafford@sheffield.ac.uk)

URL: http://www.stafford.group.shef.ac.uk/

The role of stromal-neural interactions in head and neck cancer pain and progression.

The prognosis for patients suffering with head and neck cancer (predominantly comprising head and neck squamous cell carcinoma, HNSCC) is poor, with a five-year survival rate of less than 50%. This high mortality rate presents significant palliative care challenges, particularly in terms of pain control. Many patients with terminal HNSCC report pain as having the greatest impact on their quality of life; often this pain is hard to control. Currently there is little understanding of the mechanisms producing pain in HNSCC, or indeed in many other forms of cancer, hampering the development of more effective pain control strategies. We have preliminary evidence that the mesenchymal cells surrounding a tumour may encourage nerve growth and that this may promote pain and tumour progression. In this project, we will use a variety of molecular, cellular and histological techniques to probe the molecular mechanisms underlying neural-stromal interactions and the consequences of this on tumour growth and metastasis.
For further details contact Dr Dan Lambert (d.w.lambert@sheffield.ac.uk)

Development of novel tissue-engineered conduits for peripheral nerve repair

Peripheral nerve injuries are common, giving rise to substantial disability and, in some patients, the development of chronic pain. Repair with an autologous nerve graft is not ideal as it results in both loss of function and sometimes pain from the donor site, and the outcome of the repair may be disappointing. The bioengineering challenge is to create an effective conduit that will reliably promote functional outcomes that are better than those achieved by autologous nerve grafts. The overall aim of this project is to design, manufacture and evaluate a new class of biodegradable nerve conduits with the ability to promote peripheral nerve regeneration. This project will be supervised by an interdisciplinary team of bioengineers, neuroscientists and clinicians with integrated expertise across the entire process of medical device design, fabrication and testing – from concept to clinic.
For further details please contact Professor Fiona Boissonade (f.boissonade@sheffield.ac.uk)

Chemokines in CNS disease

There is an increasing body of evidence demonstrating a role for chemokine signalling in the nervous system, where these molecules have been shown to have diverse effects in many physiological and pathological processes. Consequently, they have been implicated in a variety of CNS neurodegenerative disease states including multiple sclerosis, Parkinson’s, Huntingdon’s and Alzheimer’s diseases, and amyotrophic lateral sclerosis, as well as in chronic pain. Recent work in our laboratory provides the first demonstration that a little-studied chemokine and its receptor are expressed in the nervous system. This project will establish whether expression of this chemokine is altered in specific disease states, with initial focus on multiple sclerosis, motor neuron disease and Alzheimer’s disease where we have ready access to optimally prepared human CNS tissue and rodent models of disease. This approach will further our understanding of the disease process, and will help to identify novel therapeutic targets leading to improved treatment for these conditions.
For further details please contact Professor Fiona Boissonade (f.boissonade@sheffield.ac.uk)

Characterisation of the genotype and phenotype of epithelial cells invaded by Porphyromonas gingivalis

Many bacteria have the potential to invade epithelial cells where they may evade both the immune system and the action of therapeutic drugs. This may be an important pathogenic feature of the periodontal bacteria Porphyromonas gingivalis which can invade human cells and its presence is associated with severe forms of periodontal (gum) disease. We have evidence that not all epithelial cells are invaded to the same degree and that if the genotype and phenotype of cells containing high numbers of bacteria are compared to non-invaded cells then important information regarding the mechanism of bacterial invasion we be obtained. Pilot studies using labelled bacteria, flow cytometry and gene array analysis have suggested that this approach is technically feasible. Such information may represent novel treatment strategies to treat periodontal disease.
For further details please contact Dr Simon Whawell (s.whawell@sheffield.ac.uk)

The Development of In Vitro Models of Human Salivary Glands

At present it is not possible to fully investigate the development of a number of salivary gland disorders, such as tumour development, Sjogren’s syndrome and viral-associated infections, due to the lack of appropriate experimental tools. Currently researchers use either in vivo models or monolayer in vitro cultures of cells. Animal models carry a high economic cost but also have limitations in extrapolation of results from animal to human. Monolayer cultures do not represent the complex salivary gland structure. The aim of this project is to develop in vitro models of human submandibular and minor mucosal glands, which can be used to investigate a number of disease situations, and will also form the basis for future models including those from fresh human tissue. We will use a submandibular gland tumour cell line, which our very preliminary data indicates will grow as “small glands” when the culture conditions are altered. We will extend these studies to examine gene and protein expression (by PCR, western blotting and immunohistochemistry) of established markers so that the correct conditions for the different salivary glands can be determined.
For further details please contact Dr Lynne Bingle (l.bingle@sheffield.ac.uk)

Epithelial-fibroblast cross-talk in metastatic lymph nodes is a hallmark of aggressive disease

Oral squamous cell carcinoma (OSCC) is a sixth most common cancer in the world accounting for 4% of all cancers and 2% of all cancer deaths. It spreads primarily to neck lymph nodes (LN) with 25-30% of tumours infiltrating beyond the LN capsule resulting in extracapsular spread (ECS). This reduces the 5-year survival rate to 20% and is correlated with an increase in recurrence rate and distant metastasis. ECS biology is poorly understood and a diagnosis only possible on neck/excision specimens. Recent studies have shown that primary OSCC cells cross-talk with their surrounding stromal cells, and features of these stromal cells play an important role in OSCC growth, invasion and metastasis, clinically worsening the prognosis. However, whether OSCC-associated stroma in LNs plays a role in metastasis growth or ECS development has never been investigated. Within the OSCC resection specimens received in the unit of Maxillofacial pathology over the last 15 years, 61% of the patients had metastatic disease with 55% of these showing ECS. Our preliminary data shows that ECS-nodes had an increased number of myofibroblasts, higher number of vessels and a higher proliferation index compared to ECS-negative nodes suggesting that tumour deposits with ECS may have a more aggressive phenotype and that metastasis-associated stroma may play an important role in ECS. The current study aims to determine the role of OSCC stroma in relation to intranodal metastatic tumour deposits and correlate these stromal changes to metastasis growth and ECS. Comparison of primary and metastatic OSCC stroma, and the interaction of metastatic OSCC tumours with fibroblasts in stromal development will be studied using a range of techniques including immunohistochemistry, co-culture of various cancer cell lines with oral fibroblasts, qRT-PCR, immunoblotting and immunofluorescence, collagen contraction, scratch and proliferation assays. Adhesion of primary and metastatic OSCC cells to endothelial cells, in addition to endothelial proliferation and tubule formation will also be investigated. This project will provide better understanding of biological processes involved in OSCC metastasis and ECS and could provide insight into potential biomarkers with improved detection/treatment.
For further details please contact Dr Ali Khurram (s.a.khurram@sheffield.ac.uk)