Elucidating the stem cell basis for skin field cancerisation

Grantee: Dr Girish Patel, Senior Lecturer at the European Cancer Stem Cell Research Institute, Cardiff University, Wales

Amount: DKK 1,704,758

Grant category: Research Grants in open competition

Year: 2017

Geography: United Kingdom

Gish Patel from Cardiff University in Wales leads an international collaboration of experts in a project that investigates the signalling pathways responsible for malignant transformation of skin epithelial cells. The hope is to identify novel therapeutic targets for future drug discovery and development.

Epithelia are continually exposed to environmental carcinogens and therefore, cancers of epithelial tissues called carcinoma, account for 85% of all cancers and 78% of all cancer-associated mortality.

Many carcinomas arise from pre-malignant transformation as intraepithelial neoplasia, also referred to as field cancerisation (FC). FC can give rise to multiple primary cancers and is a feature of malignancies involving many organs, including the skin.

The team hypothesises that the mechanism in skin FC arises from dysregulation of a particular signalling pathway. This is based on results from a murine model on Epidermodysplasia Verruciformis, where the team uncovered a novel keratinocyte stem cell (KSC) basis for the FC.

This is potentially relevant to FC in other tissues and the team targets utilisation of an innovative multiple-strategy approach to determine a drug-targetable signalling pathway involved in malignant transformation and expansion of this novel KSC population.

p14-ARF in familiar melanoma: a promising target that acts as a melanocyte guardian

Grantee: Elena Papaleo, Junior Group Leader, Computational Biology Laboratory, Danish Cancer Society Research Center, Copenhagen

Amount: DKK 1,300,000

Grant category: Research Grants in open competition

Year: 2017

Geography: Denmark

Melanoma is one of the most aggressive skin cancers and its incidence in Denmark has increased over the last decade, becoming the most frequent type of cancer in young women. Despite recent discoveries on melanoma mechanisms, the prognosis for the patient is still poor and extensive research efforts are needed to clarify the molecular mechanisms involved and identify new therapeutic targets.

The outcome of this project has the potential to join these efforts by advancing the comprehension of metabolic reprogramming which forms the basis for aggressiveness and resistance to treatments in familial melanoma.

The most common mutations in familial melanoma are found in genes encoding the proteins INK4A and p14-ARF (ARF), and the basis for the project is the newly discovered function of ARF to act as guardian in human melanocytes by maintaining low levels of superoxide in conditions of mitochondrial dysfunction, protecting the melanocytes from reactive oxygen species.

The protective mechanisms mediated by ARF rely on its physical interaction with BCL-xL, a trans-membrane molecule, and this interaction could be disrupted by germline mutations of ARF. The understanding of the interaction mode and how mutations interfere with them is a fundamental step to target the BCL-xL/ARF complex for therapeutic purposes.

Carried out in a cross-disciplinary environment at the Danish Cancer Society Research Center, the project brings together experts in cellular cancer biology, structural biology, and bioinformatics. The team has access to many supercomputing facilities to speed up the data acquisition of the envisioned time-consuming simulations.

Regulation of IL-22 secretion by vitamin D in relation to Atopic Dermatitis

Grantee: Carsten Geisler, Professor and Head of Department, Department of Immunology and Microbiology, University of Copenhagen

Amount: DKK 2,779,900

Grant category: Research Grants in open competition

Year: 2017

Geography: Denmark

Atopic dermatitis (AD) is a common skin disorder affecting up to 25% of children and 3% of adults. Currently, no good treatment options exist and AD has a large impact on quality of life.

The skin of AD patients’ is characterized by inflammation caused by infiltration of both dendritic cells (DCs) and T cells leading to among other highly itching plaques. Furthermore, AD lesions are prone to infections due to a decreased barrier function of the skin.

A newly described T cell subset, Th22 cells, is suggested as a main driver of AD with an increased infiltration of both Th22 and Tc22 cells correlating with disease severity.

Treatment with narrow-band ultraviolet B radiation (NB-UVB) has proven effective in reducing the disease-scoring index of AD patients. This is accompanied by a suppression of the Th2/Th22 axis and there are ongoing clinical trials with blocking antibodies against IL-22 for AD treatment.

UVB radiation of skin is known to initiate the production of vitamin D with its potent immunomodulatory properties, and it shows that activation of human CD4+ T cells leads to a secretion of IL-21 and IL-22 – a secretion that therefore can be inhibited by vitamin D.

This project will investigate the effects of vitamin D in a physiologically relevant in vitro differentiation system of CD4+ T cells towards the Th22 lineage, targeting a better understanding of the interplay between the developments of Th22 cells in relation to AD.

Furthermore, the project will potentially provide a basis for the understanding of the molecular and cellular events in AD, and the possible symptom alleviation of patients following topical treatment with vitamin D analogues.

Replicating peeling skin diseases in a living skin model

Grantee: Professor Peter R Hull, PhD (Med) FRCPC. Head, Division of Clinical Dermatology and Cutaneous Science, Dalhousie University, Halifax, Nova Scotia

Amount: DKK 2,180,881

Grant category: Research Grants in open competition

Year: 2017

Geography: Canada

A number of chronic skin conditions have peeling of the skin as the dominant expression; akin to skin peeling following severe sunburns. In the chronic conditions, peeling is cyclical or continuous, often affecting hands, feet, or the body. Today, there is no effective treatment for these conditions, leaving patients subjected to trial and error with a variety of non-effective and often also expensive therapies.

A number of abnormal gene variants have been found to disrupt the normal maturation of the skin. Using a gene manipulation tool known as CRISPR, the team led by Dr Hull will build understanding of the role of four known genes causing skin peeling syndromes. This will be done by replicating the diseases in cell cultures grown into full thickness skin and studying the cellular and biochemical changes caused by the induced gene modifications.

Of particular interest is cathepsin B, an enzyme that has been found to play an important role in peeling associated with the skin disorder, keratolytic winter erythema.

The team’s hypothesis is that there is an important and dynamic interplay and balance between a number of enzymes in the outer layers of the skin and that if this balance favours the activity of cathepsin B, peeling results.

If this is shown, it may be clinically very relevant as there are a number of known compounds that inhibits cathepsin B and which then could be used to treat patients with chronic peeling as a consequence of their skin disorder.

The function and therapeutic potential of miR-146 family in the suppression of Type-2-cell-promoting environment in atopic dermatitis

Grantee: Ana Rebane, PhD, Head of the RNA Biology Research Group, Institute of Biomedicine and translational Medicine, University of Tartu

Amount: DKK 1,650,000

Grant category: Research Grants in open competition

Year: 2017

Geography: Estonia

Atopic dermatitis (AD) develops because of skin barrier abnormalities leading to activation of keratinocytes (KCs) and development of Type-2-cell- mediated chronic skin inflammation.

While the initial molecular events leading to induction of Type-2-cell-promoting cytokines are not well defined, it has been suggested that activation of the NF-kB pathway in response to environmental and/or intrinsic factors in KCs may be at play.

Concurrently, microRNAs – in particular miR-146a and miR-146b (miR-146a/b) – which are post-transcriptional gene expression regulators modulating various biological processes, have been shown to have an anti-inflammatory function in KCs and in the chronic phase of skin inflammation in AD.

In this project, Dr Rebane hypothesizes that miR-146a/b might inhibit AD-promoting events in the skin as these microRNAs act by targeting multiple factors in the NF-κB pathway.

Dr Rebane aims to study this relation using tissue culture and murine models, and assess the therapeutic potential in the regulation of Type-2-cell-promoting cytokines in the development of AD. In addition, it is planned to describe the expression of miR-146a/b isoforms and novel AD associated miRNAs in the skin of AD patients with the aim of detection of novel therapeutic targets.

The spatial composition and distribution of the cutaneous microbiota in atopic dermatitis and healthy skin

Grantee: Professor Thomas Bjarnsholt DMSc, PhD, Costerton Biofilm Center, Department of Immunology and Microbiology, and
 Department of Clinical Microbiology, University of Copenhagen

Amount: DKK 2,857,565

Grant category: Research Grants in open competition

Year: 2017

Geography: Denmark

In this study, Dr Bjarnsholt looks at skin microbiota and expects to illuminate consistencies and differences between atopic dermatitis and healthy skin. He will do so with focus on the cutaneous microbial composition and spatial distribution in the different layers in AD relative to healthy skin.

The skin microbiota is recognised to significantly impact human health but remains incompletely characterised in the pathogenesis of common cutaneous conditions such as AD. Understanding the three-dimensional distribution of bacteria within the skin may provide relevant insights regarding transition from healthy to diseased skin.

This study will compare the distribution and composition of the commensal, skin microbiota in dry, moist and sebaceous environments as they relate to early onset in AD patients relative to healthy volunteers.

Tape strips and sub-divided skin biopsies will be sampled and analysed by three informative, supplementary methods, i.e. cultivation, Confocal Laser Scanning Microscopy (CLSM) and Next Generation Sequencing (NGS).

This is foreseen to show how the microbiota changes in immediately adjacent regions of tissue among diseased and healthy individuals. In addition, generation of high-resolution, 3D images by confocal microscopy will allow visualisation and confirmation of the molecular and culture results.