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The efficacy of anti-angiogenic agents (AAAs) in epithelial ovarian cancer (EOC) remains unclear. Therefore, we conducted a systematic review and network meta-analysis (NMA) to synthesize evidence of their comparative effectiveness for improving overall survival (OS) among EOC patients. We searched six databases for randomized controlled trials (RCTs) from their inception to February 2021. We performed an NMA with hazard ratios (HRs) and 95%-confidence intervals (CIs) to evaluate comparative effectiveness among different AAAs in chemotherapy-naïve and recurrent EOC. P-score was used to provide an effectiveness hierarchy ranking. Sensitivity NMA was carried out by focusing on studies that reported high-risk chemotherapy-naïve, platinum-resistant, and platinum-sensitive EOC. The primary outcome was OS. We identified 23 RCTs that assessed the effectiveness of AAAs. In recurrent EOC, concurrent use of trebananib (10 mg/kg) with chemotherapy was likely to be the best option (P-score: 0.88, HR 1.67, 95% CI 0.94; 2.94). The NMA indicated that bevacizumab plus chemotherapy followed by maintenance bevacizumab (P-score: 0.99) and pazopanib combined with chemotherapy (P-score: 0.79) both had the highest probability of being the best intervention for improving OS in high-risk chemotherapy-naïve and platinum-resistant EOC, respectively. AAAs may not play a significant clinical role in non-high-risk chemotherapy-naïve and platinum-sensitive EOC.

BackgroundThe efficacy of anti-angiogenic agents (AAAs) in epithelial ovarian cancer (EOC) remains unclear. Therefore, we conducted a systematic review and network meta-analysis (NMA) to synthesize evidence of their comparative effectiveness for improving overall survival (OS) among EOC patients. MethodsWe searched six databases for randomized controlled trials (RCTs) from their inception to February 2021. We performed a NMA with hazard ratios (HRs) and 95% confidence intervals (CIs) to evaluate comparative effectiveness among different AAAs in two disease settings, chemotherapy naïve, and recurrent EOC. P-score was used to provide an effectiveness hierarchy ranking. Sensitivity NMA was carried out by focusing on studies that reported high-risk disease chemotherapy-naïve, platinum-resistant, and platinum-sensitive EOC. The primary outcome was OS.FindingsWe identified 23 RCTs (n=11,560) which assessed effectiveness of eight different AAAs. NMA results showed no significant OS difference among anti-angiogenic agents in chemotherapy-naïve. In recurrent EOC, concurrent use of trebananib (10mg/kg) and chemotherapy was likely to be the best option (P-score: 0.88, NMA estimate versus chemotherapy: HR= 1.67, 95% CI: 0.94; 2.94). The sensitivity NMA indicated that bevacizumab plus chemotherapy with maintenance treatment (P-score: 0.99) and pazopanib plus chemotherapy (P-score: 0.79) had the highest probability of being the best intervention for improving OS in high-risk chemotherapy-naïve and platinum-resistant setting, respectively. InterpretationAAAs may not play a significant clinical role in chemotherapy-naïve and platinum-sensitive EOC. Conversely, the concurrent use of trebananib with chemotherapy was likely to be the best intervention in recurrent EOC.

Background: Current guidelines for the management of bronchiectasis (BE) highlight the lack of evidence to recommend mucoactive agents, such as hypertonic saline (HTS) and carbocisteine, to aid sputum-removal as part of standard care. We hypothesise that mucoactive agents (HTS or cabocisteine, or a combination) are effective in reducing exacerbations over a 52-week period, compared to usual care. Methods: A 52-week, 2x2 factorial randomised open label trial to determine the clinical and cost-effectiveness of HTS 6% and carbocisteine for airway clearance versus usual care: CLEAR (clinical and cost-effectiveness of hypertonic saline (HTS 6%) and carbocisteine for airway clearance versus usual care). Patients will be randomised to either (i) Standard care and twice daily nebulised HTS (6%), (ii) Standard care and carbocisteine (750mg three times per day until visit 3 reducing to 750mg twice per day), (iii) Standard care and combination of twice-daily nebulised HTS and carbocisteine, or (iv) Standard care. The primary outcome is the mean number of exacerbations over 52 weeks. Key inclusion criteria: adults with a diagnosis of BE on computed tomography scans, BE as the primary respiratory diagnosis, two or more pulmonary exacerbations in the last year requiring antibiotics and production of daily sputum. Discussion: This trial’s pragmatic research design avoids the significant costs associated with double-blind trials whilst optimising rigor in other areas of trial-delivery. CLEAR will provide evidence as to whether HTS, carbocisteine or both are effective and cost-effective for BE patients. Trial registration: EudraCT Number: 2017-000664-14. (Date on which this record was first entered in the database 20/10/2017). ISRCTN89040295. (Date assigned 06/07/2018). Funder: National Institute for Health Research, Health Technology Assessment Programme (15/100/01). Sponsor: Belfast Health and Social Care Trust. Ethics Reference Number: 17/NE/0339. Protocol version: v3.0 Final_14052018. Keywords: Clinical trial protocol, factorial design, bronchiectasis, hypertonic saline, carbocisteine, exacerbation, SWAT.

Introduction: 40-45% of patients with High Grade Serous Ovarian Cancer (HGSOC) will eventually relapse with platinum resistant disease. Tothill et al and TCGA are two independent gene expression datasets which have demonstrated the presence of a mesenchymal molecular subgroup, characterised by upregulation of angiogenesis regulating genes. Angiogenesis is known to be an integral pathological feature of HGSOC and anti-angiogenics have dominated the field of drug development in EOC. However, despite this, anti-angiogenic agents have failed to demonstrate a significant impact on overall survival (OS) benefit. In this study, we asked if platinum resistance could be associated with an improved response to anti-angiogenic agents and what the underlying biological rationale for this could be. Methods: A meta-analysis of 14 phase II and III clinical trials in EOC were used to investigate the association between platinum resistance and response to anti-angiogenic agents. In addition, we analysed gene expression in 12 matched pre- and post-chemotherapy EOC samples. Novel isogenic cisplatin-resistant HGSOC cell lines were established to study the development of an angiogenic phenotype. Further studies were performed in novel ascites-derived primary cell lines from HGSOC patients with known outcomes following platinum-based chemotherapy. Result: In the clinical trial meta-analysis, an OS benefit for antiangiogenics was observed in platinum-resistant disease (p=0.029), whilst platinum-sensitive EOC only derived progression free survival (PFS) (p= Discussion: We have demonstrated that previous platinum therapy for EOC is associated with an increase in tumor PDGFα and VEGF-A expression, correlating with a response to anti-angiogenic therapies. This data suggests that platinum therapy resistance may inform the selection of EOC patients for novel antiangiogenic therapies in future clinical trials. Citation Format: Aya El Helali, Nuala McCabe, Christopher Steele, Lara Dura Perez, Christina L. O'Neill, Naomi Dickson, Niamh McGivern, Caolan Harkin, Andrena McCavigan, Reinhold J. Medina, Laura A. Knight, Stephen McQuaid, Jacqueline A. James, Caroline O. Michie, Charlie Gourley, W Glenn McCluggage, Denis P. Harkin, Richard H. Wilson, Alan W. Stitt, Richard D. Kennedy. Platinum resistance in epithelial ovarian cancer is dependent on a PDGFR alpha-VEGF-A signalling mechanism that activates downstream angiogenesis pathways [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 7.

Introduction: Platinum resistant High Grade Serous Ovarian Cancer (HGSOC) has a poor outcome with limited treatment options. Angiogenesis is a key pathological feature of ovarian cancer and anti-angiogenics have dominated the field of drug development in EOC, particularly in the second-line setting (Marachini et al 2013). In this study we asked if platinum resistance could be associated with an improved response to anti-angiogenic agents. Method: A review of phase III anti-angiogenic clinical trials was used to investigate the association between platinum resistance and response to anti-angiogenic agents. To investigate the effect of chemotherapy on predefined ovarian cancer molecular subgroups (Gourley, et al. J Clin Oncol 32:5s, 2014), we analysed 35 matched pre- and post-chemotherapy samples by gene expression. Novel isogenic cisplatin-resistant HGSOC cell lines were established to study the mechanisms of cisplatin section pressure and shift to an angiogenic phenotype. This was further validated in novel ascites-derived primary cell lines from HGSOC patients with known outcomes following platinum-based chemotherapy. Results: Critical review of 22 phase III anti-angiogenic trials suggested that there was a better response to anti-angiogenics following previous platinum-based chemotherapy. Our analysis demonstrated that 67% of treatment naïve tumours that were initially classified as non-angiogenic shifted to an angiogenic biology, which was associated with platinum resistance. Additionally we found that cisplatin resistant cancer cell lines demonstrated hallmarks of vascular mimicry and an associated increase in vessel density using an angiogenesis Matrigel plug assay in Athymic nude mice (p-value= Conclusion: We have demonstrated that platinum-resistance in HGSOC is associated with angiogenic biology supporting the use of anti-angiogenic agents in this setting. Citation Format: Aya El Helali, Nuala McCabe, Naomi Dickson, Lara Dura Perez, Denis P Harkin, Richard Wilson, Richard Kennedy. Acquired platinum resistance enhances tumour angiogenesis through activation of vascular mimicry [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 776. doi:10.1158/1538-7445.AM2017-776

The tumor suppressor protein BRCA1 orchestrates DNA repair and cell cycle arrest following DNA damage, with transcriptional regulation integral to these processes. We have identified a novel, DNA-damage responsive, interaction between BRCA1 and the zinc-finger transcription factor EGR1. EGR1 is rapidly and transiently expressed in response to a wide variety of stress stimuli and growth factors, and like BRCA1, decreased expression of EGR1 correlates with tumor formation in mammary cell lines and tissues. The stress response gene, NDRG1, was identified as a transcriptional target of BRCA1 by microarray analysis and subsequent RQ-PCR validation. NDRG1 is a known suppressor of breast cancer metastasis and we have observed a significant reduction of NDRG1 expression in breast cancer cell lines (relative to normal cell lines). Promoter analyses identified EGR1 binding motifs within the NDRG1 proximal promoter region, and EGR1 was confirmed as the transcription factor of interest by promoter assays. Downregulation of either BRCA1 or EGR1 (using a siRNA approach) resulted in a reduction in both basal and DNA-damage induced NDRG1 promoter activity, suggesting a co-regulatory mechanism. Indeed, recruitment of BRCA1 and EGR1 to the NDRG1 promoter was confirmed by ChIP assays. GST-fused BRCA1 deletion constructs showed that EGR1 specifically interacts with a C-terminal region of BRCA1 (which contains both BRCT domains). However, following DNA damage, we observed EGR1 interaction along the entire length of the BRCA1 protein, suggesting that both BRCA1 and EGR1 reside within a larger transcriptional complex upon DNA damage. In agreement with this, siRNA knockdown of either BRCA1 or EGR1 in breast cell lines (i) induced endogenous DNA damage signalling, (ii) increased intracellular ROS generation and (iii) upregulated numerous stress-response genes. To investigate transcriptional regulation downstream of this interaction we performed analyses of publically available ChIP-Seq data for both BRCA1 and EGR1, and identified a list of genomic locations (corresponding to gene promoters) at which both proteins localise. We will use these findings, in combination with our own ChIP-Seq experiments performed in the non-tumorigenic mammary cell line, 184A1, to investigate the roles of this novel complex in the maintenance of genomic stability and within normal breast biology. Citation Format: Naomi A. Dickson, Nyree T. Crawford, Paul B. Mullan. Characterization of a novel BRCA1-EGR1 interaction. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2049. doi:10.1158/1538-7445.AM2015-2049