• Head and neck cancer of unknown primary site

      McArdle, Orla; McDermott, Ronan (2013-11-21)
    • Heterogeneity in high-risk prostate cancer treated with high-dose radiation therapy and androgen deprivation therapy.

      Cagney, Daniel N; Dunne, Mary; O'Shea, Carmel; Finn, Marie; Noone, Emma; Sheehan, Martina; McDonagh, Lesley; O'Sullivan, Lydia; Thirion, Pierre; Armstrong, John (2017-08-01)
      Our aim was to assess the heterogeneity of high-risk (HR) prostate cancer managed with high-dose external beam radiotherapy (EBRT) with androgen deprivation therapy (ADT).
    • How realistic are published dose-response models? [ICORG 99-09]

      Walsh, L.; Williams, I.; O'Shea, C.; Armstrong, J.; Thirion, P.; St. Luke's Radiation Oncology Network (2010-11)
      Poster presentation - Lorraine Walsh. ASTRO 52nd annual meeting, San Diego, Nov-2010. (Int. Journal Radiation Oncol. Biol. Physics 2010; 78(3), Supplement, 3148).
    • Impact of delineation uncertainties on dose to organs at risk in CT-guided intracavitary brachytherapy.

      Duane, Frances K; Langan, Brian; Gillham, Charles; Walsh, Lorraine; Rangaswamy, Guhan; Lyons, Ciara; Dunne, Mary; Walker, Christopher; McArdle, Orla; Department of Radiation Oncology, St. Luke's Radiation Oncology Network, Rathgar, Dublin, Republic of Ireland. Electronic address: fran.duane@ctsu.ox.ac.uk. (2014-08-07)
      This study quantifies the inter- and intraobserver variations in contouring the organs at risk (OARs) in CT-guided brachytherapy (BT) for the treatment of cervical carcinoma. The dosimetric consequences are reported in accordance with the current Gynecological Groupe Européen de Curiethérapie/European Society for Therapeutic Radiology and Oncology guidelines.
    • The impact of rectal and bladder preparation in prostate radiotherapy [ICORG 05-04]

      Mullaney, L.; Thirion, P.; Coffey, M.; St Lukes Radiation Oncology Network (2011-05)
      Oral presentation - ESTRO, London, May 2011.
    • In silico analysis and DHPLC screening strategy identifies novel apoptotic gene targets of aberrant promoter hypermethylation in prostate cancer.

      Murphy, Therese M; Sullivan, Linda; Lane, Caroline; O'Connor, Lisa; Barrett, Ciara; Hollywood, Donal; Lynch, Thomas; Lawler, Mark; Perry, Antoinette S; Prostate Molecular Oncology, Institute of Molecular Medicine, Trinity College, Dublin, Ireland. murphyth@tcd.ie (Wiley, 2011-01-01)
      Aberrant DNA methylation has been implicated as a key survival mechanism in cancer, whereby promoter hypermethylation silences genes essential for many cellular processes including apoptosis. Limited data is available on the methylation profile of apoptotic genes in prostate cancer (CaP). The aim of this study was to profile methylation of apoptotic-related genes in CaP using denaturing high performance liquid chromatography (DHPLC).
    • In silico mining identifies IGFBP3 as a novel target of methylation in prostate cancer.

      Perry, A S; Loftus, B; Moroose, R; Lynch, T H; Hollywood, D; Watson, R W G; Woodson, K; Lawler, M (2007-05-21)
      Promoter hypermethylation is central in deregulating gene expression in cancer. Identification of novel methylation targets in specific cancers provides a basis for their use as biomarkers of disease occurrence and progression. We developed an in silico strategy to globally identify potential targets of promoter hypermethylation in prostate cancer by screening for 5' CpG islands in 631 genes that were reported as downregulated in prostate cancer. A virtual archive of 338 potential targets of methylation was produced. One candidate, IGFBP3, was selected for investigation, along with glutathione-S-transferase pi (GSTP1), a well-known methylation target in prostate cancer. Methylation of IGFBP3 was detected by quantitative methylation-specific PCR in 49/79 primary prostate adenocarcinoma and 7/14 adjacent preinvasive high-grade prostatic intraepithelial neoplasia, but in only 5/37 benign prostatic hyperplasia (P < 0.0001) and in 0/39 histologically normal adjacent prostate tissue, which implies that methylation of IGFBP3 may be involved in the early stages of prostate cancer development. Hypermethylation of IGFBP3 was only detected in samples that also demonstrated methylation of GSTP1 and was also correlated with Gleason score > or =7 (P=0.01), indicating that it has potential as a prognostic marker. In addition, pharmacological demethylation induced strong expression of IGFBP3 in LNCaP prostate cancer cells. Our concept of a methylation candidate gene bank was successful in identifying a novel target of frequent hypermethylation in early-stage prostate cancer. Evaluation of further relevant genes could contribute towards a methylation signature of this disease.
    • Increased mitochondrial mass in cells with functionally compromised mitochondria after exposure to both direct gamma radiation and bystander factors.

      Nugent, Sharon M E; Mothersill, Carmel E; Seymour, Colin; McClean, Brendan; Lyng, Fiona M; Murphy, James E J (2007-07)
      The bystander effect describes radiation-like damage in unirradiated cells either in the vicinity of irradiated cells or exposed to medium from irradiated cells. This study aimed to further characterize the poorly understood mitochondrial response to both direct irradiation and bystander factor(s) in human keratinocytes (HPV-G) and Chinese hamster ovarian cells (CHO-K1). Oxygen consumption rates were determined during periods of state 4, state 3 and uncoupled respiration. Mitochondrial mass was determined using MitoTracker FM. CHO-K1 cells showed significantly reduced oxygen consumption rates 4 h after exposure to 5 Gy direct radiation and irradiated cell conditioned medium (ICCM) and an apparent recovery 12-24 h later. The apparent recovery was likely due to the substantial increase in mitochondrial mass observed in these cells as soon as 4 h after exposure. HPV-G cells, on the other hand, showed a sustained increase in oxygen consumption rates after ICCM exposure and a transient increase 4 h after exposure to 5 Gy direct radiation. A significant increase in mitochondrial mass per HPV-G cell was observed after exposure to both direct radiation and ICCM. These findings are indicative of a stress response to mitochondrial dysfunction that increases the number of mitochondria per cell.
    • International Variation in Criteria for Internal Mammary Chain Radiotherapy.

      Duane, F K; McGale, P; Teoh, S; Mortimer, C; Broggio, J; Darby, S C; Dodwell, D; Lavery, B; Oliveros, S; Vallis, K A; et al. (2019-07-01)
      Aims; Evidence has emerged that internal mammary chain (IMC) radiotherapy reduces breast cancer mortality, leading to changes in treatment guidelines. This study investigated current IMC radiotherapy criteria and the percentages of patients irradiated for breast cancer in England who fulfilled them. Materials and methods; A systematic search was undertaken for national guidelines published in English during 2013–2018 presenting criteria for ‘consideration of’ or ‘recommendation for’ IMC radiotherapy. Patient and tumour variables were collected for patients who received breast cancer radiotherapy in England during 2012–2016. The percentages of patients fulfilling criteria stipulated in each set of guidelines were calculated. Results: In total, 111 729 women were recorded as receiving adjuvant breast cancer radiotherapy in England during 2012–2016 and full data were available on 48 095 of them. Percentages of patients fulfilling IMC radiotherapy criteria in various national guidelines were: UK Royal College of Radiologists 13% (6035/48 095), UK National Institute for Health and Care Excellence 18% (8816/48 095), Germany 32% (15 646/48 095), Ireland 56% (26 846/48 095) and USA 59% (28 373/48 095). Differences between countries occurred because in Ireland and the USA, treatment may be considered in some node-negative patients, whereas in the UK, treatment is considered if at least four axillary nodes are involved or for high-risk patients with one to three positive nodes. In Germany, treatment may be considered for all node-positive patients. Conclusions: There is substantial variability between countries in criteria for consideration of IMC radiotherapy, despite guidelines being based on the same evidence. This will probably lead to large variations in practice and resource needs worldwide.
    • Intravesical baclofen, bupivacaine, and oxycodone for the relief of bladder spasm.

      Wallace, Elaine; Twomey, Marie; Victory, Ray; O'Reilly, Maeve; Department of Palliative Medicine, St. Luke's Hospital, Rathgar, Dublin 6, Ireland. drelainewallace@gmail.com (2013)
    • The involvement of calcium and MAP kinase signaling pathways in the production of radiation-induced bystander effects.

      Lyng, F M; Maguire, P; McClean, B; Seymour, C; Mothersill, C (2006-04)
      Much evidence now exists regarding radiation-induced bystander effects, but the mechanisms involved in the transduction of the signal are still unclear. The mitogen-activated protein kinase (MAPK) pathways have been linked to growth factor-mediated regulation of cellular events such as proliferation, senescence, differentiation and apoptosis. Activation of multiple MAPK pathways such as the ERK, JNK and p38 pathways have been shown to occur after exposure of cells to radiation and a variety of other toxic stresses. Previous studies have shown oxidative stress and calcium signaling to be important in radiation-induced bystander effects. The aim of the present study was to investigate MAPK signaling pathways in bystander cells exposed to irradiated cell conditioned medium (ICCM) and the role of oxidative metabolism and calcium signaling in the induction of bystander responses. Human keratinocytes (HPV-G cell line) were irradiated (0.005-5 Gy) using a cobalt-60 teletherapy unit. The medium was harvested 1 h postirradiation and transferred to recipient HPV-G cells. Phosphorylated forms of p38, JNK and ERK were studied by immunofluorescence 30 min-24 h after exposure to ICCM. Inhibitors of the ERK pathway (PD98059 and U0126), the JNK pathway (SP600125), and the p38 pathway (SB203580) were used to investigate whether bystander-induced cell death could be blocked. Cells were also incubated with ICCM in the presence of superoxide dismutase, catalase, EGTA, verapamil, nifedipine and thapsigargin to investigate whether bystander effects could be inhibited because of the known effects on calcium homeostasis. Activated forms of JNK and ERK proteins were observed after exposure to ICCM. Inhibition of the ERK pathway appeared to increase bystander-induced apoptosis, while inhibition of the JNK pathway appeared to decrease apoptosis. In addition, reactive oxygen species, such as superoxide and hydrogen peroxide, and calcium signaling were found to be important modulators of bystander responses. Further investigations of these signaling pathways may aid in the identification of novel therapeutic targets.
    • Magnetic resonance imaging appearances in primary and secondary angiosarcoma of the breast.

      O'Neill, Ailbhe C; D'Arcy, Clare; McDermott, Enda; O'Doherty, Ann; Quinn, Cecily; McNally, Sorcha; Department of Breast Radiology, St. Vincent's University Hospital, Dublin, Ireland. (2014-04)
      Angiosarcomas are malignant tumours of endovascular origin. They are rare tumours accounting for 0.04-1% of all breast malignancies. Two different forms are described: primary, occurring in young women, and secondary angiosarcoma, which occurs in older women with a history of breast-conserving surgery and radiation therapy. Imaging findings on mammography and ultrasound are non-specific, but magnetic resonance imaging with dynamic contrast enhancement is more informative. We present two cases - one of primary and one of secondary angiosarcoma - and review the imaging findings.
    • Management of localised prostatic adenocarcinoma

      Rangaswamy, G; Azmi, A.; Ibrahim, N; Thirion, P; Department of Radiation Oncology, St. Luke's Hospital, Dublin, Ireland. (2011-11)
    • Manipulating the epigenome for the treatment of urological malignancies.

      O'Rourke, Colm J; Knabben, Vinicius; Bolton, Eva; Moran, Diarmaid; Lynch, Thomas; Hollywood, Donal; Perry, Antoinette S; Prostate Molecular Oncology, Institute of Molecular Medicine, Trinity College, Dublin, Ireland. (2013-05)
      Urological malignancies (cancers of the prostate, bladder, kidney and testes) account for 15% of all human cancers and more than 500,000 deaths worldwide each year. This group of malignancies is spread across multiple generations, affecting the young (testicular) through middle and old-age (kidney, prostate and bladder). Like most human cancers, urological cancers are characterized by widespread epigenetic insult, causing changes in DNA hypermethylation and histone modifications leading to silencing of tumor suppressor genes and genomic instability. The inherent stability yet dynamic plasticity of the epigenome lends itself well to therapeutic manipulation. Epigenetic changes are amongst the earliest lesions to occur during carcinogenesis and are essentially reversible (unlike mutations). For this reason, much attention has been placed over the past two decades on deriving pharmacological compounds that can specifically target and reverse such epi-mutations, either halting cancer on its developmental trajectory or reverting fully formed cancers to a more clinically manageable state. This review discusses DNA methyltransferase and histone deacetylase inhibitors that have been extensively studied in preclinical models and clinical trials for advanced and metastatic urological cancers.
    • A Method for the Prediction of Late Organ-at-Risk Toxicity After Radiotherapy of the Prostate Using Equivalent Uniform Dose.

      Fleming, Cathy; Kelly, Colin; Thirion, Pierre; Fitzpatrick, Kathryn; Armstrong, John; Clinical Trials Unit, St. Luke's Hospital, Rathgar, Dublin Ireland. (Elsevier, 2011-06-01)
      To evaluate the predictive value of equivalent uniform doses (EUD) for late bladder and rectal toxicity after high-dose three-dimensional conformal radiation therapy (3D-CRT) to the prostate.
    • MicroRNAs as putative mediators of treatment response in prostate cancer.

      O'Kelly, Fardod; Marignol, Laure; Meunier, Armelle; Lynch, Thomas H; Perry, Antoinette S; Hollywood, Donal; Prostate Molecular Oncology Research Group, Academic Unit of Clinical and Molecular Oncology, Institute of Molecular Medicine, St James' Hospital & Trinity College, University of Dublin, James's Street, Dublin 8, Ireland. (2012-05-22)
      MicroRNAs (miRNAs) are an abundant class of noncoding RNAs that function to regulate post-transcriptional gene expression, predominantly by translational repression. In addition to their role in prostate cancer initiation and progression, recent evidence suggests that miRNAs might also participate in treatment response across a range of therapies including radiation treatment, chemotherapy and androgen suppression. The mechanism of this regulation is thought to be multifactorial and is currently poorly understood. To date, only a small number of studies have examined the functional role of miRNAs in response to prostate cancer treatment. Elucidating the role of miRNAs in treatment response following radiotherapy, chemotherapy and androgen suppression will provide new avenues of investigation for the development of novel therapies for the treatment of prostate cancer.
    • Mining methylome databases.

      O'Rourke, Colm J; Murphy, Therese M; Hollywood, Donal; Perry, Antoinette S; Prostate Molecular Oncology, Institute of Molecular Medicine, Trinity College Dublin, Dublin, Ireland. orourkco@tcd.ie (2013-02)
    • Modulation of Radiation responses by pre-exposure to irradiated Cell conditioned medium.

      Maguire, Paula; Mothersill, Carmel; McClean, Brendan; Seymour, Colin; Lyng, Fiona M (Radiation Research Society, 2007-04)
      The aim of this study was to investigate whether exposure of HPV-G cells to irradiated cell conditioned medium (ICCM) could induce an adaptive response if the cells were subsequently challenged with a higher ICCM dose. Clonogenic survival and major steps in the cascade leading to apoptosis, such as calcium influx and loss of mitochondrial membrane potential, were examined to determine whether these events could be modified by giving a priming dose of ICCM before the challenge dose. Clonogenic survival data indicated an ICCM-induced adaptive response in HPV-G cells "primed" with 5 mGy or 0.5 Gy ICCM for 24 h and then exposed to 0.5 Gy or 5 Gy ICCM. Reactive oxygen species (ROS) were found to be involved in the bystander-induced cell death. Calcium fluxes varied in magnitude across the exposed cell population, and a significant number of the primed HPV-G cells did not respond to the challenge ICCM dose. No significant loss of mitochondrial membrane potential was observed when HPV-G cells were exposed to 0.5 Gy ICCM for 24 h followed by exposure to 5 Gy ICCM for 6 h. Exposure of HPV-G cells to 5 mGy ICCM for 24 h followed by exposure to 0.5 Gy ICCM for 18 h caused a significant increase in mitochondrial mass and a change in mitochondrial location, events associated with the perpetuation of genomic instability. This study has shown that a priming dose of ICCM has the ability to induce an adaptive response in HPV-G cells subsequently exposed to a challenge dose of ICCM.
    • Molecular and therapeutic advances in the diagnosis and management of malignant pheochromocytomas and paragangliomas.

      Lowery, Aoife J; Walsh, Siun; McDermott, Enda W; Prichard, Ruth S; Department of Surgery, St. Vincent's University Hospital, Dublin, Ireland. (2013)
      Pheochromocytomas (PCCs) and paragangliomas (PGLs) are rare catecholamine-secreting tumors derived from chromaffin cells originating in the neural crest. These tumors represent a significant diagnostic and therapeutic challenge because the diagnosis of malignancy is frequently made in retrospect by the development of metastatic or recurrent disease. Complete surgical resection offers the only potential for cure; however, recurrence can occur even after apparently successful resection of the primary tumor. The prognosis for malignant disease is poor because traditional treatment modalities have been limited. The last decade has witnessed exciting discoveries in the study of PCCs and PGLs; advances in molecular genetics have uncovered hereditary and germline mutations of at least 10 genes that contribute to the development of these tumors, and increasing knowledge of genotype-phenotype interactions has facilitated more accurate determination of malignant potential. Elucidating the molecular mechanisms responsible for malignant transformation in these tumors has opened avenues of investigation into targeted therapeutics that show promising results. There have also been significant advances in functional and radiological imaging and in the surgical approach to adrenalectomy, which remains the mainstay of treatment for PCC. In this review, we discuss the currently available diagnostic and therapeutic options for patients with malignant PCCs and PGLs and detail the molecular rationale and clinical evidence for novel and emerging diagnostic and therapeutic strategies.
    • Monoamine oxidase inhibitors l-deprenyl and clorgyline protect nonmalignant human cells from ionising radiation and chemotherapy toxicity.

      Seymour, C B; Mothersill, C; Mooney, R; Moriarty, M; Tipton, K F (London, Lewis, 2003-11-17)
      l-Deprenyl (R-(-)-deprenyl, selegiline) is an inhibitor of monoamine oxidase-B (MAO-B) that is known to protect nerve cells from a variety of chemical and physical insults. As apoptosis is a common mechanism of radiation-induced cell death, the effect of l-deprenyl on the survival of cultured cells and tissue explants was studied following exposure to gamma radiation. The results obtained were compared with the effects of the less-selective MAO-B inhibitor pargyline and the MAO-A inhibitor clorgyline. l-Deprenyl at a concentration of 10(-9) M protected the nontumorigenic cell line (HaCaT) and normal human urothelial explants from the effects of cobalt-60 gamma radiation, but did not protect tumorigenic human cell lines HaCaT-ras, HPV-transfected human keratinocytes (HPV-G cells), or PC3. Human bladder carcinoma explants were not protected. Clorgyline showed a smaller protective effect of normal cells, whereas pargyline had no effect. Radiation-induced delayed effects (genomic instability measured as delayed cell death) were prevented in normal cells by l-deprenyl but, interestingly, deprenyl appeared to increase the amount of delayed death in the tumorigenic cell lines. Studies using l-deprenyl prior to the exposure of nonmalignant cells to cisplatin showed that cell death due to this agent was also reduced. Treatment of cultures of nontumorigenic cells with l-deprenyl or clorgyline significantly increased the levels of the protein Bcl-2 following irradiation, but there was no such effect on the already-elevated levels of this protein in the tumour samples. Since the Bcl-2 has been shown to be an inhibitor of apoptosis or programmed cell death, this would imply that the protective effects of l-deprenyl and clorgyline involve activation of antiapoptotic pathways within the normal cell. This hypothesis is supported by data showing reduced levels of apoptosis in HaCAT cells and in normal bladder explant cultures following treatment with l-deprenyl.