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Dive into the research topics where Kieran Horgan is active.

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Featured researches published by Kieran Horgan.


The Journal of Pathology | 2003

Reduced expression of oestrogen receptor β in invasive breast cancer and its re-expression using DNA methyl transferase inhibitors in a cell line model

George Skliris; Kailas Munot; Sandra M. Bell; Pauline J Carder; Sally Lane; Kieran Horgan; Mark Lansdown; Alicia T Parkes; Andrew M. Hanby; Alexander F. Markham; Valerie Speirs

To gain insights into the possible role of oestrogen receptor (ER) β in breast carcinogenesis, immunohistochemical analysis of ER β was performed on 512 breast specimens encompassing normal (n = 138), pure ductal carcinoma in situ (n = 16), invasive cancers (n = 319), lymph node metastases (n = 31), and recurrences (n = 8). Real‐time polymerase chain reaction (PCR) was used to investigate the methylation status of the ER β gene in the ER β negative breast cancer cell lines SkBr3 and MDA‐MB‐435. A gradual reduction in, but not a complete loss of, ER β expression was observed during the transition from normal and pre‐invasive lesions to invasive cancers, where ER β was lost in 21% of cases. This was more pronounced in invasive ductal than in lobular carcinomas, a significantly higher proportion of which were ER β‐positive (74% compared with 91%, respectively, p = 0.0004). Examination of paired primary cancers with their axillary lymph node metastases showed that if ER β was present in the primary tumour, it persisted in the metastasis. Treatment of ER β‐negative cell lines with DNA methyl transferase inhibitors restored ER β expression, providing experimental evidence that silencing of ER β in breast carcinomas could be due to promoter hypermethylation. These results suggest that loss of ER β expression is one of the hallmarks of breast carcinogenesis and that it may be a reversible process involving methylation. Copyright


Surgeon-journal of The Royal Colleges of Surgeons of Edinburgh and Ireland | 2011

Surgery induced immunosuppression

Brian Hogan; Mark B. Peter; Hg Shenoy; Kieran Horgan; Thomas A. Hughes

Surgery and anaesthesia result in a variety of metabolic and endocrine responses, which result in a generalised state of immunosuppression in the immediate post-operative period. Surgery induced immunosuppression has been implicated in the development of post-operative septic complications and tumour metastasis formation. In addition the effectiveness of many treatments in the adjuvant setting is dependent on a functioning immune system. By understanding the mechanisms contributing to surgery-induced immunosuppression, surgeons may undertake strategies to minimise its effect and reduce potential short-term and long-term consequences to patients.


Breast Cancer Research | 2011

Male breast carcinoma: increased awareness needed.

Jonathan White; O Kearins; David Dodwell; Kieran Horgan; Andrew M. Hanby; Valerie Speirs

Male breast carcinoma is a rare condition. Few male breast cancer-specific epidemiological or clinical trial data are available - our understanding of male breast cancer thus comes from studies of female breast cancer, painting an inaccurate picture when it comes to determining contributing factors. Clinicians report an increase in diagnoses of male breast cancer but this has not been formally reported. We therefore undertook a review of data obtained from four western nations: England, Scotland, Canada and Australia. When adjusted for age, this review clearly showed an increase in the incidence of male breast cancer over a 15-year period. Reasons for the increased incidence are discussed in the context of suggested risk factors such as BRCA2 and lifestyle changes over the past few decades. The clinical management of male breast carcinoma is considered, in particular the potential role of aromatase inhibitors and fulvestrant and targeting pathways involving prolactin and androgen receptor.


Cellular Oncology | 2012

Circulating microRNA profiles reflect the presence of breast tumours but not the profiles of microRNAs within the tumours.

Victoria J. Cookson; Michael A. Bentley; Brian Hogan; Kieran Horgan; Bruce E. Hayward; Lee Hazelwood; Thomas A. Hughes

BackgroundExtra-cellular microRNAs have been identified within blood and their profiles reflect various pathologies; therefore they have potential as disease biomarkers. Our aim was to investigate how circulating microRNA profiles change during cancer treatment. Our hypothesis was that tumour-related profiles are lost after tumour resection and therefore that comparison of profiles before and after surgery would allow identification of biomarker microRNAs. We aimed to examine whether these microRNAs were directly derived from tumours, and whether longitudinal expression monitoring could provide recurrence diagnoses.MethodsPlasma was obtained from ten breast cancer patients before and at two time-points after resection. Tumour tissue was also obtained. Quantitative PCR were used to determine levels of 367 miRNAs. Relative expressions were determined after normalisation to miR-16, as is typical in the field, or to the mean microRNA level.Results210 microRNAs were detected in at least one plasma sample. Using miR-16 normalisation, we found few consistent changes in circulating microRNAs after resection, and statistical analyses indicated that this normalisation was not justifiable. However, using data normalised to mean microRNA expression we found a significant bias for levels of individual circulating microRNAs to be reduced after resection. Potential biomarker microRNAs were identified, including let-7b, let-7g and miR-18b, with higher levels associated with tumours. These microRNAs were over-represented within the more highly expressed microRNAs in matched tumours, suggesting that circulating populations are tumour-derived in part. Longitudinal monitoring did not allow early recurrence detection.ConclusionsWe concluded that specific circulating microRNAs may act as breast cancer biomarkers but methodological issues are critical.


British Journal of Cancer | 2009

Expression of COX-2, NF-κB-p65, NF-κB-p50 and IKKα in malignant and adjacent normal human colorectal tissue

M P Charalambous; Tracy Lightfoot; Valerie Speirs; Kieran Horgan; Nigel J. Gooderham

BACKGROUND:Cyclooxygenase-2 (COX-2) is selectively over-expressed in colorectal tumours. The mechanism of COX-2 induction in these tumours is not fully understood, although evidence suggests a possible link between nuclear factor (NF)-κB and COX-2. We hypothesised an association between COX-2 expression and NF-κB-p65, NF-κB-p50 and IκB-kinase-α (IKKα) in both epithelial and stromal cells in human colorectal cancer.Methods:Using immunohistochemistry, we measured COX-2, NF-κB-p65, NF-κB-p65 nuclear localisation sequence (NLS), NF-κB-p50, NF-κB-p50 NLS and IKKα protein expression in matched colorectal biopsy samples comprising both non-tumour and adjacent tumour tissue from 32 patients with colorectal cancer.Results:We have shown that stromal cells of malignant and surrounding normal colorectal tissue express COX-2. In all cell types of malignant tissue, and in vascular endothelial cells (VECs) of neighbouring normal tissue, COX-2 expression was strongly associated with NF-κB-p65 expression (Pearsons correlation, P=0.019 for macrophages, P=0.001 for VECs, P=0.002 for fibroblasts (malignant tissue), and P=0.011 for VECs (non-malignant tissue)) but not NF-κB-p50 or IKKα.Conclusions:These data suggest that in these cells COX-2 induction may be mediated through activation of the canonical NF-κB pathway. Finally, the lack of association between COX-2, NF-κB-p65 or IKKα in stromal cells with the clinical severity of colorectal cancer as determined by Dukes stage, suggests that COX-2, NF-κB-p65 and IKKα expression are possibly early post-initiation events, which could be involved in tumour progression.


Genes, Chromosomes and Cancer | 2000

Novel translocation of the BCL10 gene in a case of mucosa associated lymphoid tissue lymphoma

Rajgopal Achuthan; Sandra M. Bell; J.P. Leek; Paul Roberts; Kieran Horgan; A.F. Markham; Peter Selby; Kenneth A. MacLennan

Interest has focused on a recently identified gene, BCL10, thought to play an important role in the genesis of extranodal, marginal zone (MALT) lymphomas. This gene belongs to a family containing caspase recruitment domains (CARD), that are involved in the apoptotic pathway. Translocations of the BCL10 gene to the immunoglobulin heavy chain locus at 14q32 have been described. We report herein a case of MALT lymphoma showing t(1; 2)(p22; p12). The translocation was shown to involve the BCL10 gene and the immunoglobulin kappa light chain locus by fluorescence in situ hybridization.


Clinical Cancer Research | 2008

Carcinoembryonic antigen cell adhesion molecule 6 predicts breast cancer recurrence following adjuvant tamoxifen.

Loaie Maraqa; Michele Cummings; Mark B. Peter; Abeer M. Shaaban; Kieran Horgan; Andrew M. Hanby; Valerie Speirs

Purpose: Tamoxifen remains therapy of choice for premenopausal estrogen receptor α–positive breast cancer. However, resistance and recurrence are serious problems. Our previous work indicated that carcinoembryonic antigen cell adhesion molecule 6 (CEACAM6) was significantly up-regulated in tamoxifen-resistant (TAMr) MCF-7 derivatives. The aim of this study was to determine the functional role of CEACAM6 in endocrine-resistant breast cancer and to retrospectively test whether it was predictive of resistance in a large cohort of breast cancers with long-term follow-up. Experimental Design: siRNA silencing of CEACAM6 was done in TAMr cells and effects on clonogenicity and endocrine sensitivity were determined. CEACAM6 immunohistochemistry was done on a tissue microarray comprising 108 relapsed primary human breast cancers and 243 tamoxifen-sensitive controls. Results: siRNA-mediated silencing of CEACAM6 reduced both clonogenicity and anchorage-dependent and anchorage-independent growth of TAMr cells. Importantly, CEACAM6 silencing restored sensitivity of TAMr cells to 4-hydroxytamoxifen and proliferative response to 17β-estradiol. Immunohistochemistry showed significantly more CEACAM expression in the relapsed group compared with nonrelapsed controls [35 of 108 (33.3%) and 32 of 243 (13.2%), respectively; odds ratio, 3.16 (95% confidence interval, 1.83-5.47); P < 0.0001]. Additionally, we derived an outcome predictor model based on CEACAM expression that restratified patients in the Nottingham prognostic index intermediate-risk group into either higher-risk or lower-risk group. Conclusions: Our data support an important role for CEACAM6 in endocrine resistance, which can serve as a powerful predictor of future recurrence.


British Journal of Surgery | 2014

Systematic review and meta‐analysis of cytokeratin 19‐based one‐step nucleic acid amplification versus histopathology for sentinel lymph node assessment in breast cancer

J. P. Tiernan; Eldo Verghese; A. Nair; S. Pathak; Baek Kim; J. White; Helene Thygesen; Kieran Horgan; Andrew M. Hanby

One‐step nucleic acid amplification (OSNA) is a new rapid assay for detecting breast cancer metastases during surgery, saving a second procedure for patients requiring an axillary clearance. Many centres in the UK and abroad have adopted OSNA in place of routine histopathology, despite no published meta‐analysis. The aim of this systematic review and meta‐analysis was to determine whether intraoperative OSNA for lymph node assessment is comparable to routine histopathology in the detection of clinically relevant metastases.


The Journal of Pathology | 2004

Do metastases metastasize

Catherine R Tait; David Dodwell; Kieran Horgan

Metastatic disease is a major cause of morbidity and mortality. However, it is not clear if all metastases originate from the primary tumour or whether metastases themselves have the capacity to metastasize. In this review, the evidence for the latter phenomenon, and its biological and clinical implications, is discussed. Copyright


Tumori | 2012

Patient-reported outcomes in breast oncology: a review of validated outcome instruments.

Anastasios Kanatas; Galina Velikova; Brenda Roe; Kieran Horgan; Naseem Ghazali; Richard Shaw; Simon N. Rogers

AIMS AND BACKGROUND Patient-reported outcomes (PROs) include areas of health-related quality of life but also broader concepts such as patient satisfaction with care. The aim of this review is to give an account of all instruments with potential use in patients with a history of treatment for breast cancer (including surgery, chemotherapy and/or radiotherapy) with evidence of validation in the breast cancer population. METHODS All instruments included in this review were identified as PRO measures measuring breast-related quality of life and/or satisfaction that had undergone development and validation with breast oncology patients. We specifically looked for PRO measures examining patient satisfaction and/or quality of life after breast cancer treatment. Following an evaluation of 323 papers, we identified 15 instruments that were able to satisfy our inclusion criteria. RESULTS These instruments are the EORTC QOL-C30 and QLQ-BR23 (European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Breast Cancer Module), the FACT-B (Functional Assessment of Cancer Therapy-Breast Cancer), the SLDS-BC (Satisfaction with Life Domains Scale for Breast Cancer), the BIBCQ (Body Image after Breast Cancer Questionnaire), the HIBS (Hopwood Body Image Scale), the PBIS (Polivy Body Image Scale), the MBROS (Michigan Breast Reconstruction Outcomes Study) Satisfaction and Body Image Questionnaires, the BREAST-Q, the BCTOS (Breast Cancer Treatment Outcome Scale), the BCQ, the FACT-ES (Functional Assessment of Cancer Therapy-Endocrine System), the MAS (Mastectomy Attitude Scale), and the Breast Cancer Prevention Trial Symptom Checklist (BCPT). CONCLUSIONS Suggestions for future directions include (1) to use and utilize validated instruments tailored to clinical practice; (2) to develop a comprehensive measurement of surgical outcome requiring the combination of objective and subjective measures; (3) to aim for a compromise between these two competing considerations in the form of a scale incorporating both generalizability in cancer-related QOL and specificity in breast cancer issues.

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David Dodwell

St James's University Hospital

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Nisha Sharma

St James's University Hospital

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Abeer M. Shaaban

Queen Elizabeth Hospital Birmingham

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Brian Hogan

Leeds General Infirmary

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