Study protocol for the St James's Hospital, Tallaght University Hospital, Trinity College Dublin Allied Researchers' (STTAR) Bioresource for COVID-19

Background: The current coronavirus disease 2019 (COVID-19) pandemic began in Ireland with the first confirmed positive case in March 2020. In the early stages of the pandemic clinicians and researchers in two affiliated Dublin hospitals identified the need for a COVID-19 biobanking initiative to support and enhance research into the disease. Through large scale analysis of clinical, regional, and genetic characteristics of COVID-19 patients, biobanks have helped identify, and so protect, at risk patient groups The STTAR Bioresource has been created to collect and store data and linked biological samples from patients with SARS-CoV-2 infection and healthy and disease controls. Aim: The primary objective of this study is to build a biobank, to understand the clinical characteristics and natural history of COVID-19 infection with the long-term goal of research into improved disease understanding, diagnostic tests and treatments. Methods: This is a prospective dual-site cohort study across two tertiary acute university teaching hospitals. Patients are recruited from inpatient wards or outpatient clinics. Patients with confirmed COVID-19 infection as well as healthy and specific disease control groups are recruited.  Biological samples are collected and a case report form detailing demographic and medical background is entered into the bespoke secure online Dendrite database. Impact: The results of this study will be used to inform national and international strategy on health service provision and disease management related to COVID-19. In common with other biobanks, study end points  evolve over time as new research questions emerge. They currently include patient survival, occurrence of severe complications of the disease or its therapy, occurrence of persistent symptoms following recovery from the acute illness and vaccine responses.

Abstract 3382: A systematic approach to the study of cancer stem cells applied to ovarian cancer

Background: Tumorgenicity studies show that Cancer Stem Cells (CSCs) but not their differentiated counterparts efficiently generate tumors. Therapeutically targeting CSCs could remove the malignant potential from tumours, while circumventing chemoresistance, relapse and metastasis. CSCs are difficult to study as they usually represent a small fraction of tumors. We will present a systematic approach we developed to investigate CSCs within any malignancy. We will present the data obtained thus far in the application of this system to the study of Ovarian CSCs. Methods: We developed a four phase model for investigating CSCs: Screening - Validation - Characterisation - Identification of novel therapeutic targets. Six cell lines modelling various stages of ovarian cancer (A2780, A2780cis, IGROV-1, IGROV(CDDP), SK-OV-3 and 59M) and one cell line (HIO-80) modelling non malignant ovarian surface epithelium were screened for the presence of CSCs and somatic stem cells respectively. Three flow cytometry based screens were implemented; ALDEFLUOR, Hoechst Side Population and Cell Surface Protein Screens. Cells of interest were isolated via Fluorescence Activated Cell Sorting. Mouse Tumorgenicity and Asymmetric Division Assays have been developed to validate putative CSCs (pCSCs) as true CSCs. Hypoxic growth, chemotherapeutic and matrigel invasion assays have all been developed to investigate the role of Ovarian CSCs in these commonly observed phenotypes of Ovarian cancer. Results: Six pCSC populations have been identified. No overlap has been observed between the three screening approaches. ALDEFLUOR identified pCSCs within A2780 and A2780cis. Hoechst Side Population identified pCSCs within IGROV-1 and IGROV(CDDP). CD44/CD117 identified pCSCs within SK-OV-3 and 59M. No somatic stem cells were identified within HIO-80. To date pCSC and non-pCSCs have been sorted from two cell lines. In both models the isolated pCSCs regenerated the non-pCSC phenotype. Both the isolated pCSCs and non-pCScs from each model are resistance to cisplatin and paclitaxel. In both cases the parent lines were chemoresistant, so this finding is not unexpected. All pCSCs are currently being validated via Mouse Tumourgenicity and Single Cell Asymmetric Division Assays. All validated CSCs will be described. Conclusion: A systematic approach has been established for the isolation and study of CSCs. Each ‘type’ of ovarian CSC appears to be mutually exclusive. This may reflect different stages/histologies of ovarian disease, or perhaps the selective conditions of tissue culture. pCSCs have been identified within chemosensitive cell lines. Investigation of the differences between chemoresistant and chemosensitive CSCs could elucidate the mechanisms behind chemoresistant relapse.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 3382. doi:1538-7445.AM2012-3382

Abstract LB-338: Stabilisation of MAD2 expression through inhibition of miR-433; A novel mechanism for restoring chemo-responsiveness in ovarian tumours

Epithelial ovarian carcinoma (EOC) is characterised by late diagnosis and recurrences, both of which contribute to the high morbidity and mortality of this cancer. Unfortunately, EOC has an innate susceptibility to become chemo-resistant. Specifically, up to 30% of patients may not respond to current standard chemotherapy (paclitaxel and platinum in combination) and of those who have an initial response, some patients relapse within a few months. Therefore, in order to improve patient outcome it is crucial to establish what factors influence a patients' individualised response to chemotherapy. We analysed MAD2 protein expression in a patient cohort of 35 ovarian tumours and a panel of 5 ovarian cancer cell lines. We have demonstrated that low nuclear MAD2 expression intensity was significantly associated with chemo-resistant ovarian tumours (p=0.0136). Moreover, in vitro studies of the 5 ovarian cancer cell lines revealed that reduced MAD2 expression was associated with paclitaxel resistance. In silico analysis identified a putative miR-433 binding domain in the MAD2 3′UTR and expression profiling of miR-433 in the ovarian cancer cell lines showed that low MAD2 protein expression was associated with high miR-433 levels. In vitro over-expression of miR-433 attenuated MAD2 protein expression with a concomitant increase in cellular resistance to paclitaxel. Over-expression of a morpholino oligonucleotide that blocks miR-433 binding to MAD2 3′UTR stabilised MAD2 protein expression and protects from miR-433 induced degradation. Furthermore, miR-433 expression analysis in 35 ovarian tumour samples revealed that high miR-433 expression was associated with advanced stage presentations (p=0.0236). In conclusion, ovarian tumours that display low nuclear MAD2 intensity are chemo-resistant and stabilising MAD2 expression by antagonising miR-433 activity is a potential mechanism for restoring chemo-responsiveness in these tumours.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr LB-338. doi:10.1158/1538-7445.AM2011-LB-338

A rapid microwave-in situ hybridization method for the definitive diagnosis of oral hairy leukoplakia: comparison with immunohistochemistry

As a diagnostic technique, in situ hybridization requires a long processing time, a degree of expertise and may be difficult to handle routinely in some laboratories. To simplify the in situ hybridization method, we have modified a microwave in situ hybridization technique and applied it to oral hairy leukoplakia (OHL) biopsies obtained from 10 HIV-seropositive patients (definitively diagnosed by a conventional in situ hybridization technique) with appropriate controls. It was necessary to design a novel chamber to avoid drying of sections during the hybridization step. This modified microwave in situ hybridization technique was equispecific and equisensitive to the conventional technique and it shortens the hybridization time from overnight incubation to 14 minutes. To determine the sensitivity of our microwave in situ hybridization method we applied it to previously documented tongue tissue obtained from an AIDS autopsy without clinical evidence of OHL, but found to contain Epstein-Barr virus (EBV) by conventional in situ hybridization. This tissue specimen acted as a low EBV copy number, positive control. The sensitivity of immunohistochemistry using three different commercial detection kits was compared to that of in situ hybridization on the same tissues, following optimisation steps. This included the use of 2 cycles of primary and biotinylated secondary antibodies (antibody double cycling). Clearly positive signals for EBV were detected in all OHL biopsies with the Vectastain Elite ABC and the Histostain-SP kits. The sensitivity of the three commercial detection kits was evaluated at immunohistochemistry level by their application to the low-EBV copy number positive control specimen. Signals for EBV antigen in the low copy number positive control specimen were obtained only with the Vectastain Elite ABC kit. This indicates that, in this application, use of the Vectastain Elite ABC kit gives comparable sensitivity for immunohistochemistry to that found by in situ hybridiation.