Invited Speakers - Abstracts

Prof Stephen R Pennington

President-Elect HUPO, UCD Conway Institute, Ireland

Discovery, Development and Delivery of Protein Biomarkers for Cancer Patient Benefit

Despite a few decades of proteomics research and the apparent discovery of hundreds if not thousands of new protein biomarkers, the number of that have been developed to the stage of being used routinely in clinical practice is disappointingly low.  So, whilst there’s huge interest in the development of new biomarker and major unmet clinical needs as yet biomarker development and delivery is proving very challenging. Many aspects of these challenges have been described and reviewed.

In this presentation, early-stage efforts to develop multiplexed protein signatures will be described. The process we adopt begins with identifying the unmet clinical need and using it to define the context and intended use of a new diagnostic test. Then having established potential biomarkers we exploit the flexibility, sensitivity and specificity of targeted mass spectrometry approaches to develop assays to measure multiplexed protein signatures for biomarker evaluation. Drawing on examples in prostate cancer our on-going efforts to develop and validate multiplexed protein assays that are sufficiently robust, reproducible and operationally routine for use as advanced diagnostic tests will be presented.

Prof Julie Gehl

Clinical Professor, Center for Experimental Drug and Gene Electrotransfer (C*EDGE), Zealand University Hospital, University of Copenhagen, Denmark

Electrochemotherapy and calcium electroporation; development of new treatments for cancer 

Brief electric pulses may be used to transiently permeabilize cell membranes (electroporation), and this can be used to increase uptake of drugs in cancer cells. Of note the increase in cytotoxicity of the chemotherapeutic agent bleomycin is increased several hundred folds, enabling highly efficient once-only treatment of tumours that can be accessed with an electric field. Also, calcium may be used as a cytotoxic drug as supraphysiological doses of calcium are poorly tolerated by tumour cells. Novel electrodes are being developed, enabling treatment of not only cutaneous tumours but also tumours in internal organs. This talk will explain the scientific basis of electroporation-based drug delivery, will describe present clinical results and expand thoughts on future therapies using electroporation-based drug delivery.

Dr Eva Szegezdi

Director of Blood Cancer Biobank Ireland

The differential effects of decitabine and 5-azacytidine on AML cells – implications for NK cell-based immunotherapy

Delphine Ohayon, Andrea Tirincsi, Hojjat Alizadeh Zeinabad, Eva Szegezdi

Apoptosis Research Centre and Blood Cancer Network Ireland, National Universiy of Ireland, Galway

Decitabine and 5-azacytidine are DNA hypomethylating agents (HMA). They inhibit DNA methyltransferases (DNMT) by getting incorporated into the DNA where they form an irreversible complex with DNMTs. 5-azacytidine and 5-aza-2-deoxycytidine (decitabine) are nucleoside analogues. They differ from each other in that decitabine is a DNA nucleoside (contain deoxy-ribose), while 5-azacytidine is an RNA nucleoside.

Decitabine and 5-azacytidine are widely used for the treatment of elderly acute myeloid leukaemia (AML) patients due to their relatively mild side effects.

AML is characterised with aggressive growth of immature myeloid cells derived from malignant hematopoietic stem or progenitor cells (HSPC), termed leukemic stem cells (LSCs). DNMTs are central for HSPC differentiation and proliferation but the effect of HMAs on LSCs is poorly characterised.

In this study, we show that decitabine and 5-azacytidine have an opposing effect on the expression of the interleukin-3 receptor (IL3Ra, AKA CD123), a characteristic receptor of malignant LSCs associated with IL-3-driven proliferation. While decitabine enhanced the expression of CD123 on the cell surface, 5-azacytidine had a tendency of reducing it. By measuring protein expression rate we found that 5-azacytidine robustly blocks general protein synthesis and decitabine has a much milder effect.

As CD123 is a selective marker of LSCs, it is a good target for immunotherapy. Here we show that AML cells treated with decitabine can be opsonised more effectively with an anti-CD123 antibody than 5-azacytidine treated cells and these cells can be recognised and killed by natural killer (NK) cells, thus offering a treatment strategy to effectively target LSCs, the recognised cause of drug resistance and disease relapse in AML.

Dr Patrick Caswell

Wellcome Trust Centre for Cell-Matrix Research, University of Manchester, UK

Controlling tumour-stroma interactions through endocytic trafficking

The endocytosis of cell surface receptors, and subsequent trafficking through the endocytic system, regulates their ability to switch on downstream signalling modules. It is now clear that endocytosis controls signalling during proliferation, differentiation and migration of cells, and plays an important role in cancer progression. Our work has focused on how the endolysosomal system controls the master regulators of the cytoskeleton, RhoGTPases, in cells migrating in 3D-matrix.

We have shown that Rab11-driven recycling of integrins and co-cargo receptors controls cancer cell migration in 3D-matrix. Rab11 and its effector Rab-coupling protein (RCP) coordinate signals that control the architecture of F-actin protrusions, by switching the balance of RhoGTPase signalling to favour RhoA activation and formin-dependent filopodia formation to generate actin-spike protrusions (rather than lamellipodia). We are now focusing on the functions of Rab11 trafficking pathways in metastasis of high grade serous ovarian cancer to the omentum, a fatty peritoneal fold that is the major colonisation site in this form of cancer.

Dr Sudipto Das B.Tech, M.Res, PhD

Honorary Lecturer at Royal College of Surgeons in Ireland

Dissecting genetic and epigenetic alterations mediated metastatic colorectal cancer progression

Sudipto Das1,2*, Kirsha Naicker1*, Rut Klinger1, Bruce Moran1, Elton Rexhepaj3 Yue Fan1, Rory Casey4, Fredrick Ponten3, Karen Jirstrom5, Jacintha O’ Sullivan4, William M Gallagher2, Donal J Brennan6§, Darran P O’Connor1,2§

1Conway Institute, University College Dublin,2 Department of Molecular and Cellular Therapeutics, Royal College of Surgeons in Ireland, Dublin, 3Uppsala University, Uppsala Sweden4 Trinity College Dublin,5Department of Clinical Sciences, Lund University, Sweden,6 University of Queensland, Australia              *Equal Contribution, § Shared Senior Authorship

Despite continual efforts in developing more effective diagnostic and therapeutic options, metastatic colorectal cancer (mCRC) associated survival remains significantly low compared to non-metastatic CRC. This talk focuses on a targeted DNA methylation approach, which has allowed us to identify tumour specific differentially methylated enhancer regions which control disease-associated genes such as SATB2, a member of a family of Special AT-rich Binding proteins and a novel transcription factor that orchestrates gene expression. Previously, we described SATB2 as colorectal cancer (CRC) diagnostic marker, here, we assess the precise functional role of SATB2 in the development and progression of colorectal cancer, initiating from the pro-inflammatory phenotype. Differential expression of SATB2 was observed in colorectal cancer with the early pre-neoplastic tissue demonstrating highest SATB2 levels, which diminishes in adenomas followed by complete loss of SATB2 expression in metastatic disease. Functionally, we demonstrate that siRNA-mediated knock down of SATB2 in SW480 cells was associated with the acquisition of an aggressive phenotype. Gene set enrichment analysis of gene expression data derived from two independent CRC cohorts (n=776), revealed that loss of SATB2 mRNA expression was associated with a TH2 cytokine response and checkpoint genes like CTLA4 and PD1. Intriguingly, SATB2 expression was associated with chromosomal stability as knock-down of SATB2 resulted in an increase of anaphase bridging. Given the relationship between SATB2, chromosomal instability and local inflammatory response, SATB2 protein expression was assessed in a large cohort of patients with Ulcerative Colitis (UC) some of whom developed UC related carcinoma. SATB2 protein expression decreased across the disease spectrum from normal to UC to dysplasia to carcinoma, suggesting that SATB2 expression can be used to monitor UC patients at risk of developing CRC. Taken together, these findings for the first time demonstrate the role of SATB2 as potential master immune-regulator in colon cancer.

Dr Urska Kamensek

Institute of Oncology Ljubljana, Department of Experimental Oncology, Zaloska cesta 2, 1000 Ljubljana, Slovenia              ukamensek@onko-i.si

Gene electrotransfer for cancer immunotherapy

Gene electrotransfer (GET) is one of the most efficient non-viral gene therapy approaches for localized gene transfer into tumors in vivo. Therefore, it is especially promising for delivering different cytokines that are toxic if administered systemically. Currently, electrotransfer of plasmids encoding the cytokine interleukin 12 (IL-12) is approaching clinical use for treatment of various superficial solid tumors. Plasmids used in ongoing IL-12 GET clinical trials in the USA, contain antibiotic resistance genes and are thus, according to safety recommendations of the European Medicines Agency, not suitable for clinical trials in the EU. Hence, in our group we are striving to prepare plasmids without antibiotic resistance genes. Likewise, we are investigating different immunological capacities of GET: from using GET as an adjuvant to standard local ablative therapies or to induce in situ vaccination, to investigating the adjuvant effect of plasmid DNA itself.

In one of the immunological GET based approaches, we utilize concomitant intratumoral GET of two plasmids: a plasmid encoding a potent cytotoxic cytokine tumour necrosis factor alpha (TNFα) to induce in situ vaccination and a plasmid encoding an immunostimulatory cytokine IL-12 to boost the primed local immune response into a systemic one. The results of our recent study in a mouse melanoma tumour model confirmed the feasibility and effectiveness of the proposed approach in eliciting a potent and durable antitumor response. Furthermore, the ability of the approach to induce in situ vaccination was indicated by the expansion of effector immune cells in lymph nodes, and vitiligo-like depigmentation of the treated area. However, further studies are needed to directly prove the systemic effectiveness, such as the abscopal effect, of the approach and to push the local effectiveness from 80 to 100%. In addition, the approach needs to be tested in other tumour models, especially since one of the advantages of in situ vaccination is its ability to harness the patient’s own immune system and tumour’s own tumour-associated antigens, meaning it has the potential to be effective in different cancer types.

Prof John Callan

The Norbrook Chair in Pharmaceutical Science, Ulster University, UK

Ultrasound Targeted Microbubble Destruction for the targeted Chemo-Sonodynamic Therapy of Pancreatic Cancer.

Abstract: Pancreatic cancer has the lowest survival rate among the 21 most common forms of cancer with only 5% of patients surviving 5 years following diagnosis. Surgery remains the only cure for pancreatic cancer but surgery with curative intent is only possible in approximately 20% of patients. The remaining 80% of patients present with either metastatic disease (40%) or locally advanced/borderline resectable disease (LAPC / BRPC) (40%). In recent years, significant effort has focussed on treating LAPC / BRPC patients with neo-adjuvant chemo- or chemo/radiotherapy in an attempt to downstage their tumours and increase the proportion of patients eligible for surgery. Unfortunately, the chemotherapy used in these treatment regimes is extremely toxic and results in significant off-target side effects. We have developed a microbubble based platform capable of carrying drug payloads on their surface and oxygen gas in their core. We have demonstrated the ability to target delivery of the oxygen gas and drug payloads to murine pancreatic cancer tumours using externally applied ultrasound to disrupt (burst) the microbubbles in the tumour vasculature. We have also demonstrated that combining conventional cancer chemotherapeutics with sonodynamic therapy (SDT) produces a significantly improved tumour response compared to chemotherapy or radiotherapy alone. In this talk, we present our pre-clinical results to date and outline the next steps toward translation of this technology to the clinic.

Dr Verena Murphy

Translational Research Leader Operations Lead for CNS and Paediatric Studies, Cancer Trials Ireland

Translational Research in Cancer Trials Ireland

Cancer Trials Ireland is a not for profit clinical trials organisation, which was founded in 1996 (as All Ireland Cooperative Research Group, ICORG). The aim was to create more research opportunities for patients by putting a formal structure in place to make Ireland more attractive as a location to international cancer research groups and the pharmaceutical industry. Today it counts more than 95% of the island’s cancer treating professionals and a large amount of academic cancer researchers among its membership ensuring that research into cancer develops at a national level across all localities.

Cancer Trials Ireland collaborates with both national cancer research groups (e.g. BREASTPREDICT and the Blood Cancer Network), as well as leading international groups such as ECOG, NSABP, TRIO, ANZUP, UNC Cancer Network and CRUK. Currently, the Cancer Trials Ireland portfolio consists of 154 trials in various different stages (in development, open to accrual, in follow-up), of which 42 are translational/registry, 25 are radiotherapy and 87 are clinical studies addressing all major cancer types.

Resulting from a strategic decision in 2009, a resource for translational research and a requirement for all in-house studies to include a biological sample collection has been put in place. Since then, the majority of Cancer Trials Ireland sponsored studies include translational sub-studies, which together with related clinical data present an invaluable source for cancer research projects. In addition, Standard Operating Procedures (SOPs) for sample collection and processing were put in place to ensure consistently high quality of the samples, which are a prerequisite for good and meaningful research.

Prof Mark Corrigan

Director of Cork Breast Research Centre (CBRC) UCC, Director of Core Surgical training & Consultant Surgeon Cork University Hospital

We need to stop translating

Language is important. Our goal is to improve the outcomes of patients with cancer. The term ‘translating’ infers the use of separate languages by at least two participants. Different languages create the need to translate, therefore creating barriers. Barriers are impediments to accomplishing goals. Our aim to date has been to improve translation, however, we now need to look at developing an organisational vernacular that facilities the incorporation of clinical, basic biomedical and theory directed research into delivering improved outcomes for patients with cancer. Accepting the significant talent and experience available to us, we need to construct a model of medical research that brings us beyond needing to translate and instead one that immediately harmonises the available skillset towards our stated objectives. The evolution of patient, hospital, university and commercial industry conglomerates in targeted areas will help facilitate this.

Prof Jacintha O'Sullivan

Professor in Translational Oncology, Director of MSc. in Translational Oncology, Trinity Translational Medicine Institute, Department of Surgery, Trinity College Dublin,

Is Angiogenesis still an attractive target in Colorectal Cancer drug discovery?

Colorectal cancer (CRC) is the third most frequent cause of cancer death worldwide, responsible for over six hundred thousand deaths per year. 25%-30% of CRC patients present with metastases at diagnosis. Despite the introduction of molecularly targeted therapies, the five-year survival rate for patients with metastatic CRC remains at a dismal rate of 12%. Targeted therapies for these patients include cetuximab (Erbitux) which targets the epithelial growth factor (EGF) receptor, and bevacizumab (Avastin) which is a humanized monoclonal antibody that targets vascular endothelial growth factor (VEGF). However, response rates to bevacizumab are only about 40% or less. In contrast to cetuximab where assessing KRAS mutation status does predict survival, there is very limited or inconclusive data on biomarkers for predicting response to bevacizumab treatment.

Selection of patients for bevacizumab therapy based on molecular predictors of individual tumours is regarded as an important treatment strategy for these patients, however, there are currently no biomarkers used clinically to predict benefit to Bevacizumab targeted treatment, to monitor treatment response or to assess whether and when to discontinue treatment. This is a major clinical challenge. Without appropriate tools, clinicians are now using bevacizumab in unselected patients without awareness of pre-existing or emerging resistance. Therefore the identification of robust biomarker panels with demonstrated biological relevance to VEGF inhibition in order to predict or monitor the efficacy of Bevacimuab treatment is a challenging field.

In my talk, I will discuss the work we have done on biomarker screening in this field. We have also taken a theranostic approach linking this diagnostic work with developing novel small molecule drugs that may have utility in those tumours non-responsive to bevacizumab using human ex vivo models and in vivo mouse studies. The output of these studies is focused on delivering a more personalised medicine approach in treating metastatic CRC patients.