8 results on '"Robert D. Morgan"'
Search Results
2. Replication catastrophe is responsible for intrinsic PAR glycohydrolase inhibitor-sensitivity in patient-derived ovarian cancer models
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Camilla Coulson-Gilmer, Robert D. Morgan, Louisa Nelson, Bethany M. Barnes, Anthony Tighe, René Wardenaar, Diana C. J. Spierings, Helene Schlecht, George J. Burghel, Floris Foijer, Sudha Desai, Joanne C. McGrail, and Stephen S. Taylor
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High-grade serous ovarian cancer ,PARG inhibitor ,DNA replication ,Replication stress ,Gene expression signature ,Predictive biomarkers ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Abstract Background Patients with ovarian cancer often present at advanced stage and, following initial treatment success, develop recurrent drug-resistant disease. PARP inhibitors (PARPi) are yielding unprecedented survival benefits for women with BRCA-deficient disease. However, options remain limited for disease that is platinum-resistant and/or has inherent or acquired PARPi-resistance. PARG, the PAR glycohydrolase that counterbalances PARP activity, is an emerging target with potential to selectively kill tumour cells harbouring oncogene-induced DNA replication and metabolic vulnerabilities. Clinical development of PARG inhibitors (PARGi) will however require predictive biomarkers, in turn requiring an understanding of their mode of action. Furthermore, differential sensitivity to PARPi is key for expanding treatment options available for patients. Methods A panel of 10 ovarian cancer cell lines and a living biobank of patient-derived ovarian cancer models (OCMs) were screened for PARGi-sensitivity using short- and long-term growth assays. PARGi-sensitivity was characterized using established markers for DNA replication stress, namely replication fibre asymmetry, RPA foci, KAP1 and Chk1 phosphorylation, and pan-nuclear γH2AX, indicating DNA replication catastrophe. Finally, gene expression in sensitive and resistant cells was also examined using NanoString or RNAseq. Results PARGi sensitivity was identified in both ovarian cancer cell lines and patient-derived OCMs, with sensitivity accompanied by markers of persistent replication stress, and a pre-mitotic cell cycle block. Moreover, DNA replication genes are down-regulated in PARGi-sensitive cell lines consistent with an inherent DNA replication vulnerability. However, DNA replication gene expression did not predict PARGi-sensitivity in OCMs. The subset of patient-derived OCMs that are sensitive to single-agent PARG inhibition, includes models that are PARPi- and/or platinum-resistant, indicating that PARG inhibitors may represent an alternative treatment strategy for women with otherwise limited therapeutic options. Conclusions We discover that a subset of ovarian cancers are intrinsically sensitive to pharmacological PARG blockade, including drug-resistant disease, underpinned by a common mechanism of replication catastrophe. We explore the use of a transcript-based biomarker, and provide insight into the design of future clinical trials of PARGi in patients with ovarian cancer. However, our results highlight the complexity of developing a predictive biomarker for PARGi sensitivity.
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- 2021
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3. Distinct transcriptional programs stratify ovarian cancer cell lines into the five major histological subtypes
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Bethany M. Barnes, Louisa Nelson, Anthony Tighe, George J. Burghel, I-Hsuan Lin, Sudha Desai, Joanne C. McGrail, Robert D. Morgan, and Stephen S. Taylor
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Ovarian cancer ,Non-negative matrix factorization ,RNA sequencing ,Subtype classification ,Machine learning ,Transcriptomics ,Medicine ,Genetics ,QH426-470 - Abstract
Abstract Background Epithelial ovarian cancer (OC) is a heterogenous disease consisting of five major histologically distinct subtypes: high-grade serous (HGSOC), low-grade serous (LGSOC), endometrioid (ENOC), clear cell (CCOC) and mucinous (MOC). Although HGSOC is the most prevalent subtype, representing 70–80% of cases, a 2013 landmark study by Domcke et al. found that the most frequently used OC cell lines are not molecularly representative of this subtype. This raises the question, if not HGSOC, from which subtype do these cell lines derive? Indeed, non-HGSOC subtypes often respond poorly to chemotherapy; therefore, representative models are imperative for developing new targeted therapeutics. Methods Non-negative matrix factorisation (NMF) was applied to transcriptomic data from 44 OC cell lines in the Cancer Cell Line Encyclopedia, assessing the quality of clustering into 2–10 groups. Epithelial OC subtypes were assigned to cell lines optimally clustered into five transcriptionally distinct classes, confirmed by integration with subtype-specific mutations. A transcriptional subtype classifier was then developed by trialling three machine learning algorithms using subtype-specific metagenes defined by NMF. The ability of classifiers to predict subtype was tested using RNA sequencing of a living biobank of patient-derived OC models. Results Application of NMF optimally clustered the 44 cell lines into five transcriptionally distinct groups. Close inspection of orthogonal datasets revealed this five-cluster delineation corresponds to the five major OC subtypes. This NMF-based classification validates the Domcke et al. analysis, in identifying lines most representative of HGSOC, and additionally identifies models representing the four other subtypes. However, NMF of the cell lines into two clusters did not align with the dualistic model of OC and suggests this classification is an oversimplification. Subtype designation of patient-derived models by a random forest transcriptional classifier aligned with prior diagnosis in 76% of unambiguous cases. In cases where there was disagreement, this often indicated potential alternative diagnosis, supported by a review of histological, molecular and clinical features. Conclusions This robust classification informs the selection of the most appropriate models for all five histotypes. Following further refinement on larger training cohorts, the transcriptional classification may represent a useful tool to support the classification of new model systems of OC subtypes.
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- 2021
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4. Effect of oxaliplatin plus 5-fluorouracil or capecitabine on circulating and imaging biomarkers in patients with metastatic colorectal cancer: a prospective biomarker study
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Reem D. Mahmood, Danielle Shaw, Tine Descamps, Cong Zhou, Robert D. Morgan, Saifee Mullamitha, Mark Saunders, Nerissa Mescallado, Alison Backen, Karen Morris, Ross A. Little, Susan Cheung, Yvonne Watson, James P. B. O’Connor, Alan Jackson, Geoff J. M. Parker, Caroline Dive, and Gordon C. Jayson
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Colorectal cancer ,Angiogenesis ,Biomarkers ,Bevacizumab ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Abstract Background Patients with metastatic colorectal cancer are treated with cytotoxic chemotherapy supplemented by molecularly targeted therapies. There is a critical need to define biomarkers that can optimise the use of these therapies to maximise efficacy and avoid unnecessary toxicity. However, it is important to first define the changes in potential biomarkers following cytotoxic chemotherapy alone. This study reports the impact of standard cytotoxic chemotherapy across a range of circulating and imaging biomarkers. Methods A single-centre, prospective, biomarker-driven study. Eligible patients included those diagnosed with colorectal cancer with liver metastases that were planned to receive first line oxaliplatin plus 5-fluorouracil or capecitabine. Patients underwent paired blood sampling and magnetic resonance imaging (MRI), and biomarkers were associated with progression-free survival (PFS) and overall survival (OS). Results Twenty patients were recruited to the study. Data showed that chemotherapy significantly reduced the number of circulating tumour cells as well as the circulating concentrations of Ang1, Ang2, VEGF-A, VEGF-C and VEGF-D from pre-treatment to cycle 2 day 2. The changes in circulating concentrations were not associated with PFS or OS. On average, the MRI perfusion/permeability parameter, K trans, increased in response to cytotoxic chemotherapy from pre-treatment to cycle 2 day 2 and this increase was associated with worse OS (HR 1.099, 95%CI 1.01–1.20, p = 0.025). Conclusions In patients diagnosed with colorectal cancer with liver metastases, treatment with standard chemotherapy changes cell- and protein-based biomarkers, although these changes are not associated with survival outcomes. In contrast, the imaging biomarker, K trans, offers promise to direct molecularly targeted therapies such as anti-angiogenic agents.
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- 2021
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5. A living biobank of ovarian cancer ex vivo models reveals profound mitotic heterogeneity
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Louisa Nelson, Anthony Tighe, Anya Golder, Samantha Littler, Bjorn Bakker, Daniela Moralli, Syed Murtuza Baker, Ian J. Donaldson, Diana C. J. Spierings, René Wardenaar, Bethanie Neale, George J. Burghel, Brett Winter-Roach, Richard Edmondson, Andrew R. Clamp, Gordon C. Jayson, Sudha Desai, Catherine M. Green, Andy Hayes, Floris Foijer, Robert D. Morgan, and Stephen S. Taylor
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Science - Abstract
High-grade serous ovarian carcinoma is often associated with TP53 mutation and chromosomal instability (CIN). Here, the authors generate ex vivo cultures from biopsies and ascites of patients and perform characterization to evaluate CIN mechanisms and compare drug sensitivity with patient responses.
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- 2020
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6. Psychosexual Morbidity in Women With Ovarian Cancer: Evaluation by Germline BRCA Gene Mutational Status
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Chloe A. Logue, MBChB, MRes, Julia Pugh, BNurs (hons), MSc, PGDip, Philip Foden, BSc, MSc, Reem D. Mahmood, MBChB, MRCP, Robert D. Morgan, MBBS, Claire Mitchell, MBBS, MRCP, PhD, Jurjees Hasan, MSc, MD, FRCP, Andrew R. Clamp, MA, BMBCh, PhD, and Gordon C. Jayson, PhD, FRCP
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Ovar* ,BRCA ,Psychosex* ,Menopaus* ,Medicine - Abstract
ABSTRACT: Introduction: Up to 75% of women with ovarian cancer experience psychosexual morbidity and approximately 15–20% of women with ovarian cancer have a germline BRCA1/2 mutation (gBRCAm). However, psychosexual morbidity remains unexplored in women with gBRCAm ovarian cancer. Aim: Given their younger age, genetic diagnosis, breast cancer risk, and increased prevalence of surgically-induced menopause, we aim to assess whether women with gBRCAm ovarian cancer experience distinct psychosexual morbidity. Methods: Psychosexual morbidity was investigated in 2 cohorts of women with ovarian cancer: women with gBRCAm ovarian cancer vs women with gBRCA wildtype (gBRCAwt) ovarian cancer. Between August 2019 and March 2020, women with high-grade serous carcinoma of the ovary, Fallopian tube or primary peritoneum were approached in clinic or telephoned and invited to take part. Exclusion criteria included: women with alternative histology; women admitted from clinic; and women who lacked capacity to independently complete the questionnaire. The Female Sexual Function Index (FSFI) and background information were collected at a single time-point per patient. Scores below 26.55 were interpreted to suggest psychosexual dysfunction. Main Outcome Measure: Responses including total and domain FSFI scores, self-reported psychosexual problems and interest in psychosexual support were compared. Results: Of 103 women approached, 53% returned questionnaires. In this exploratory analysis, women with gBRCAm ovarian cancer were significantly younger (51–60 years vs 61–70 years, gBRCAwt, P = .010). There was a trend towards increased prevalence of surgical menopause (57% vs 27%, P = .097) and breast surgery (53% vs 22%, P = .132, gBRCAm vs gBRCAwt, respectively). Women with gBRCAm ovarian cancer scored higher in the FSFI questionnaire, particularly women under 60 years (15.1 vs 2.7, P = .070), approaching significance. Women with gBRCAm ovarian cancer expressed more interest for face-to-face services (P = .018), especially psychosexual therapy (65% vs 30%) and more often felt the service was insufficient, approaching significance (71% vs 44%, gBRCAm vs gBRCAwt, respectively, P = .076). Conclusion: Women with gBRCAm ovarian cancer are younger, express more interest for specialist psychosexual support and potentially different psychosexual problems, warranting further exploration.Logue C, Pugh J, Foden P, et al., Psychosexual Morbidity in Women With Ovarian Cancer: Evaluation by Germline BRCA Gene Mutational Status. Sex Med 2022;10:100465.
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- 2022
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7. Palliative home parenteral nutrition in patients with ovarian cancer and malignant bowel obstruction: experiences of women and family caregivers
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Anne Marie Sowerbutts, Simon Lal, Jana Sremanakova, Andrew R. Clamp, Gordon C. Jayson, Antje Teubner, Lisa Hardy, Chris Todd, Anne-Marie Raftery, Eileen Sutton, Robert D. Morgan, Alexander J. Vickers, and Sorrel Burden
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Parenteral nutrition ,Ovarian cancer ,Bowel obstruction ,Phenomenology ,Qualitative ,Special situations and conditions ,RC952-1245 - Abstract
Abstract Background Malnutrition is a problem in advanced cancer, particularly ovarian cancer where malignant bowel obstruction (MBO) is a frequent complication. Parenteral nutrition is the only way these patients can received adequate nutrition and is a principal indication for palliative home parenteral nutrition (HPN). Giving HPN is contentious as it may increase the burden on patients. This study investigates patients’ and family caregivers’ experiences of HPN, alongside nutritional status and survival in patients with ovarian cancer and MBO. Methods This mixed methods study collected data on participant characteristics, clinical details and body composition using computed tomography (CT) combined with longitudinal in-depth interviews underpinned by phenomenological principles. The cohort comprised 38 women with ovarian cancer and inoperable MBO admitted (10/2016 to 12/ 2017) to a tertiary referral hospital. Longitudinal interviews (n = 57) were carried out with 20 women considered for HPN and 13 of their family caregivers. Results Of the 38 women, 32 received parenteral nutrition (PN) in hospital and 17 were discharged on HPN. Nutritional status was poor with 31 of 33 women who had a CT scan having low muscle mass, although 10 were obese. Median overall survival from admission with MBO for all 38 women was 70 days (range 8–506) and for those 17 on HPN was 156 days (range 46–506). Women experienced HPN as one facet of their illness, but viewed it as a “lifeline” that allowed them to live outside hospital. Nevertheless, HPN treatment came with losses including erosion of normality through an impact on activities of daily living and dealing with the bureaucracy surrounding the process. Family caregivers coped but were often left in an emotionally vulnerable state. Conclusions Women and family caregivers reported that the inconvenience and disruption caused by HPN was worth the extended time they had at home.
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- 2019
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8. Screening tool for malignant bowel obstruction in relapsed, metastatic ovarian cancer
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Robert D Morgan, Andrew R Clamp, Jurjees Hasan, Gordon C Jayson, Sofia Stamatopoulou, Nerissa Mescallado, Geoff Saunders, Richard Welch, and Claire Mitchell
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Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Background Malignant bowel obstruction (MBO) is a common cause of morbidity and mortality in women diagnosed with ovarian cancer. Earlier detection of MBO may improve patient outcomes. There are currently no screening tools to assist detection.Aim We report a screening questionnaire that can be used to detect MBO, and how the severity score for key clinical symptoms correlate with radiological evidence of MBO from ovarian cancer.Design A case–control study in which patients with relapsed, metastatic ovarian cancer were asked to answer 10 questions related to key clinical symptoms associated with intestinal obstruction. The study group included women with CT-confirmed MBO, whereas the control group had no evidence of MBO. Patients scored each question according to severity from 1 (least severe) to 5 (most severe).Setting/participants Between 1 June and 31 December 2016, 37 women completed the screening questionnaire.Results Patients in the study group (n=17) reported significantly higher (ie, more severe) scores for abdominal pain, nausea, vomiting and constipation. In contrast, differences in severity scores between groups did not differ significantly in response to questions regarding abdominal swelling, borborygmi, diarrhoea or loss of appetite. All patients in the study group more frequently stated that their symptoms had deteriorated within the 2 months prior to completing the questionnaire.Conclusion Here we report the key clinical symptoms associated with radiologically-confirmed MBO in relapsed, metastatic ovarian cancer. We recommend healthcare practitioners focus on these specific symptoms during patient consultations in order to improve risk stratification of MBO.
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- 2019
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