Imperial College London

DrSilviaOttaviani

Faculty of MedicineDepartment of Surgery & Cancer

Honorary Lecturer
 
 
 
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Contact

 

+44 (0)20 7594 2823silvia.ottaviani

 
 
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Location

 

ICTEM buildingHammersmith Campus

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Summary

 

Publications

Publication Type
Year
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33 results found

Correia JS, Miron Barroso S, Hutchings C, Ottaviani S, Somuncuoğlu B, Castellano L, Porter AE, Krell J, Georgiou TKet al., 2023, How does the polymer architecture and position of cationic charges affect cell viability?, Polymer Chemistry, Vol: 14, Pages: 303-317, ISSN: 1759-9954

Polymer chemistry, composition and molar mass are factors that are known to affect cytotoxicity however the influence of polymer architecture has not been investigated systematically. In this study the influence of the position of the cationic charges along the polymer chain on cytotoxicity was investigated while keeping constant the other polymer characteristics. Specifically, copolymers of various architectures, based on a cationic pH responsive monomer, 2-(dimethylamino)ethyl methacrylate (DMAEMA) and a non-ionic hydrophilic monomer, oligo(ethylene glycol)methyl ether methacrylate (OEGMA) were engineered and their toxicity towards a panel of cell lines investigated. Of the seven different polymer architectures examined, the block-like structures were less cytotoxic than statistical or gradient/tapered architectures. These findings will assist in developing future vectors for nucleic acid delivery.

Journal article

Mirón-Barroso S, Correia JS, Frampton AE, Lythgoe MP, Clark J, Tookman L, Ottaviani S, Castellano L, Porter AE, Georgiou TK, Krell Jet al., 2022, Polymeric carriers for delivery of RNA cancer therapeutics, Non-Coding RNA, Vol: 8, Pages: 58-58, ISSN: 2311-553X

As research uncovers the underpinnings of cancer biology, new targeted therapies have been developed. Many of these therapies are small molecules, such as kinase inhibitors, that target specific proteins; however, only 1% of the genome encodes for proteins and only a subset of these proteins has ‘druggable’ active binding sites. In recent decades, RNA therapeutics have gained popularity due to their ability to affect targets that small molecules cannot. Additionally, they can be manufactured more rapidly and cost-effectively than small molecules or recombinant proteins. RNA therapeutics can be synthesised chemically and altered quickly, which can enable a more personalised approach to cancer treatment. Even though a wide range of RNA therapeutics are being developed for various indications in the oncology setting, none has reached the clinic to date. One of the main reasons for this is attributed to the lack of safe and effective delivery systems for this type of therapeutic. This review focuses on current strategies to overcome these challenges and enable the clinical utility of these novel therapeutic agents in the cancer clinic.

Journal article

Pardo O, Chrysostomou S, Roy R, Prischi F, Thamlikitkul L, Chapman KL, Mufti U, Peach R, Ding L, Hancock D, Moore C, Molina-Arcas M, Mauri F, Pinato DJ, Abrahams JM, Ottaviani S, Castellano L, Giamas G, Pascoe J, Moonamale D, Pirrie S, Gaunt C, Billingham L, Steven NM, Cullen M, Hrouda D, Winkler M, Post J, Cohen P, Salpeter SJ, Bar V, Zundelevich A, Golan S, Leibovici D, Lara R, Klug DR, Yaliraki SN, Barahona M, Wang Y, Downward J, Skehel JM, Ali MMU, Seckl MJet al., 2021, Repurposed floxacins targeting RSK4 prevent chemoresistance and metastasis in lung and bladder cancer, Science Translational Medicine, Vol: 13, ISSN: 1946-6234

Lung and bladder cancers are mostly incurable because of the early development of drug resistance and metastatic dissemination. Hence, improved therapies that tackle these two processes are urgently needed to improve clinical outcome. We have identified RSK4 as a promoter of drug resistance and metastasis in lung and bladder cancer cells. Silencing this kinase, through either RNA interference or CRISPR, sensitized tumor cells to chemotherapy and hindered metastasis in vitro and in vivo in a tail vein injection model. Drug screening revealed several floxacin antibiotics as potent RSK4 activation inhibitors, and trovafloxacin reproduced all effects of RSK4 silencing in vitro and in/ex vivo using lung cancer xenograft and genetically engineered mouse models and bladder tumor explants. Through x-ray structure determination and Markov transient and Deuterium exchange analyses, we identified the allosteric binding site and revealed how this compound blocks RSK4 kinase activation through binding to an allosteric site and mimicking a kinase autoinhibitory mechanism involving the RSK4’s hydrophobic motif. Last, we show that patients undergoing chemotherapy and adhering to prophylactic levofloxacin in the large placebo-controlled randomized phase 3 SIGNIFICANT trial had significantly increased (P = 0.048) long-term overall survival times. Hence, we suggest that RSK4 inhibition may represent an effective therapeutic strategy for treating lung and bladder cancer.

Journal article

Zagorac S, de Giorgio A, Dabrowska A, Kalisz M, Casas-Vila N, Cathcart P, Yiu A, Ottaviani S, Degani N, Lombardo Y, Tweedie A, Nissan T, Vance KW, Ulitsky I, Stebbing J, Castellano Let al., 2021, SCIRT lncRNA restrains tumorigenesis by opposing transcriptional programs of tumor-initiating cells., Cancer Research, Vol: 81, Pages: 580-593, ISSN: 0008-5472

In many tumors, cells transition reversibly between slow-proliferating tumor-initiating cells (TIC) and their differentiated, faster-growing progeny. Yet how transcriptional regulation of cell cycle and self-renewal genes is orchestrated during these conversions remains unclear. In this study, we show that as breast TIC form, a decrease in cell-cycle and increase in self-renewal gene expression is coregulated by SOX2 and EZH2, which colocalize at CpG islands. This pattern was negatively controlled by a novel long non-coding RNA (lncRNA) that we name SCIRT, which was markedly upregulated in tumorspheres but colocalized with and counteracted EZH2 and SOX2 during cell cycle and self-renewal regulation to restrain tumorigenesis. SCIRT specifically interacted with EZH2 to increase EZH2 affinity to FOXM1 without binding the latter. In this manner, SCIRT induced transcription at cell cycle gene promoters by recruiting FOXM1 through EZH2 to antagonize EZH2-mediated effects at target genes. Conversely, on stemness genes, FOXM1 was absent and SCIRT antagonized EZH2 and SOX2 activity, balancing towards repression. These data suggest that the interaction of a lncRNA with EZH2 can alter the affinity of EZH2 for its protein binding partners to regulate cancer cell state transitions.

Journal article

Stebbing J, Nievas GS, Falcone M, Youhanna S, Richardson P, Ottaviani S, Shen JX, Sommerauer C, Tiseo G, Ghiadoni L, Virdis A, Monzani F, Rizos LR, Forfori F, Avendano-Cespedes A, De Marco S, Carrozzi L, Lena F, Sanchez-Jurado PM, Lacerenza LG, Cesira N, Caldevilla-Bernardo D, Perrella A, Niccoli L, Mendez LS, Matarrese D, Goletti D, Tan Y-J, Monteil V, Dranitsaris G, Cantini F, Farcomeni A, Dutta S, Burley SK, Zhang H, Pistello M, Li W, Romero MM, Pretel FA, Simon-Talero RS, Garcia-Molina R, Kutter C, Felce JH, Nizami ZF, Miklosi AG, Penninger JM, Menichetti F, Mirazimi A, Abizanda P, Lauschke VMet al., 2021, JAK inhibition reduces SARS-CoV-2 liver infectivity and modulates inflammatory responses to reduce morbidity and mortality, Science Advances, Vol: 7, Pages: 1-15, ISSN: 2375-2548

Using AI, we identified baricitinib as having antiviral and anticytokine efficacy. We now show a 71% (95% CI 0.15 to 0.58) mortality benefit in 83 patients with moderate-severe SARS-CoV-2 pneumonia with few drug-induced adverse events, including a large elderly cohort (median age, 81 years). An additional 48 cases with mild-moderate pneumonia recovered uneventfully. Using organotypic 3D cultures of primary human liver cells, we demonstrate that interferon-α2 increases ACE2 expression and SARS-CoV-2 infectivity in parenchymal cells by greater than fivefold. RNA-seq reveals gene response signatures associated with platelet activation, fully inhibited by baricitinib. Using viral load quantifications and superresolution microscopy, we found that baricitinib exerts activity rapidly through the inhibition of host proteins (numb-associated kinases), uniquely among antivirals. This reveals mechanistic actions of a Janus kinase-1/2 inhibitor targeting viral entry, replication, and the cytokine storm and is associated with beneficial outcomes including in severely ill elderly patients, data that incentivize further randomized controlled trials.

Journal article

Sims JT, Krishnan V, Chang C-Y, Eagle SM, Casalini G, Rodgers GH, Bivi N, Nickoloff BJ, Konrad RJ, de Bono S, Higgs RE, Benschop RJ, Ottaviani S, Cardosa A, Nirula A, Corbellino M, Stebbing Jet al., 2021, Characterization of the cytokine storm reflects hyperinflammatory endothelial dysfunction in COVID-19, Journal of Allergy and Clinical Immunology, Vol: 147, Pages: 107-111, ISSN: 0091-6749

BackgroundPhysicians treating COVID-19 patients increasingly believe that the hyperinflammatory acute stage of COVID-19 results in a cytokine storm. The circulating biomarkers seen across the spectrum of COVID-19 have not been characterized compared to healthy controls, but such analyses are likely to yield insights into the pursuit of interventions that adequately reduce the burden of these cytokine storms.ObjectiveTo identify and characterize the host inflammatory response to SARS-CoV-2 infection, we assessed levels of proteins related to immune responses and cardiovascular disease, in patients stratified as mild, moderate, and severe, versus matched healthy controls.MethodsBlood samples from adult patients hospitalized with COVID-19 were analyzed using high-throughput and ultrasensitive proteomic platforms and compared with age- and sex-matched healthy controls to provide insights into differential regulation of 185 markers.ResultsResults indicate a dominant hyperinflammatory milieu in the circulation and vascular endothelial damage markers within COVID-19 patients, and strong biomarker association with patient response as measured by Ordinal scale. As patients progress, we observe statistically significant dysregulation of IFNγ, IL-1RA, IL-6, IL-10, IL-19, MCP-1, -2, -3, CXCL9, CXCL10, CXCL5, ENRAGE and PARP-1. Furthermore, in a limited series of patients who were sampled frequently confirming reliability and reproducibility of our assays, we demonstrate that intervention with baricitinib attenuates these circulating biomarkers associated with the cytokine storm.ConclusionThese wide-ranging circulating biomarkers show an association with increased disease severity and may help stratify patients and selection of therapeutic options. They also provide insights into mechanisms of SARS-CoV-2 pathogenesis and the host response.

Journal article

Ottaviani S, Stebbing J, 2020, What is the best drug to treat COVID-19? The need for randomized controlled trials, Medicine, Vol: 1, Pages: 9-10, ISSN: 1357-3039

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is currently the biggest public health challenge to the biomedical community of the last century. Despite multiple public health measures,1, 2, 3 there remains an urgent need for pharmacologic therapies to treat infected patients, minimize mortality, and decrease pressures on intensive care units and health systems and optimally, they should also decrease subsequent transmission.

Journal article

Stebbing J, Krishnan V, de Bono S, Ottaviani S, Casalini G, Richardson PJ, Monteil V, Lauschke VM, Mirazimi A, Youhanna S, Tan Y-J, Baldanti F, Sarasini A, Terres JAR, Nickoloff BJ, Higgs RE, Rocha G, Byers NL, Schlichting DE, Nirula A, Cardoso A, Corbellino M, Sacco Baricitinib Study Groupet al., 2020, Mechanism of baricitinib supports artificial intelligence-predicted testing in COVID-19 patients, EMBO Molecular Medicine, Vol: 12, Pages: 1-15, ISSN: 1757-4676

Baricitinib, is an oral Janus kinase (JAK)1/JAK2 inhibitor approved for the treatment of rheumatoid arthritis (RA) that was independently predicted, using artificial intelligence (AI)-algorithms, to be useful for COVID-19 infection via a proposed anti-cytokine effects and as an inhibitor of host cell viral propagation. We evaluated the in vitro pharmacology of baricitinib across relevant leukocyte subpopulations coupled to its in vivo pharmacokinetics and showed it inhibited signaling of cytokines implicated in COVID-19 infection. We validated the AI-predicted biochemical inhibitory effects of baricitinib on human numb-associated kinase (hNAK) members measuring nanomolar affinities for AAK1, BIKE, and GAK. Inhibition of NAKs led to reduced viral infectivity with baricitinib using human primary liver spheroids. These effects occurred at exposure levels seen clinically. In a case series of patients with bilateral COVID-19 pneumonia, baricitinib treatment was associated with clinical and radiologic recovery, a rapid decline in SARS-CoV-2 viral load, inflammatory markers, and IL-6 levels. Collectively, these data support further evaluation of the anti-cytokine and anti-viral activity of baricitinib and supports its assessment in randomized trials in hospitalized COVID-19 patients.

Journal article

Peng L, Xiao K, Ottaviani S, Stebbing J, Wang Y-Jet al., 2020, A real-world disproportionality analysis of FDA Adverse Event Reporting System (FAERS) events for baricitinib., Expert Opinion on Drug Safety, Vol: 19, Pages: 1505-1511, ISSN: 1474-0338

BACKGROUND: Baricitinib is approved for the treatment of rheumatoid arthritis (RA). The authors retrospectively investigated adverse events (AEs) by data-mining a self-reporting database to better understand toxicities, especially since it has been used during the coronavirus disease 2019 (COVID-19) pandemic. METHODS: A reporting odds ratio (ROR) was used to detect the risk signals from the data in the US Food and Drug Administration (FDA) adverse event reporting system database (FAERS). The definition relied on system organ class (SOCs) and preferred terms (PTs) by the Medical Dictionary for Regulatory Activities (MedDRA). RESULTS: The search retrieved 1,598 baricitinib-associated cases within the reporting period: 86 PTs with significant disproportionality were retained. Infections including 'herpes zoster,' 'oral herpes,' and 'herpes virus infection' were found at a similar rate to those reported in trials, and such events were rare. Reports emerged for several thrombotic adverse events, while these events were also rare. Unexpected safety signals as opportunistic infections were detected. Serious outcomes as death and life-threatening outcomes accounted for 9.76% of the reported cases. CONCLUSIONS: The incidence of these AEs does not appear above the background expected. These data are consistent with routine clinical observations and suggest the importance of pharmacovigilance.

Journal article

Richardson PJ, Ottaviani S, Prelle A, Stebbing J, Casalini G, Corbellino Met al., 2020, CNS penetration of potential anti-COVID-19 drugs., Journal of Neurology, Vol: 267, Pages: 1880-1882, ISSN: 0340-5354

Journal article

Ottaviani S, Stebbing J, Frampton AE, Zagorac S, Krell J, de Giorgio A, Trabulo SM, Nguyen VTM, Magnani L, Feng H, Giovannetti E, Funel N, Gress TM, Jiao LR, Lombardo Y, Lemoine NR, Heeschen C, Castellano Let al., 2019, Author Correction: TGF-beta induces miR-100 and miR-125b but blocks let-7a through LIN28B controlling PDAC progression, Nature Communications, Vol: 10, ISSN: 2041-1723

Journal article

Chrysostomou S, Roy R, Prischi F, Chapman K, Mufti U, Mauri F, Bellezza G, Abrahams J, Ottaviani S, Castellano L, Giamas G, Hrouda D, Winkler M, Klug D, Yaliraki S, Barahona M, Wang Y, Ali M, Seckl M, Pardo Oet al., 2019, Abstract 1775: Targeting RSK4 prevents both chemoresistance and metastasis in lung cancer, AACR Annual Meeting on Bioinformatics, Convergence Science, and Systems Biology, Publisher: American Association for Cancer Research, Pages: 1-2, ISSN: 0008-5472

Lung cancer is the commonest cause of cancer death worldwide with a five-year survival rate of less than five percent for metastatic tumors. Non-small cell lung cancer (NSCLC) accounts for 80% of lung cancer cases of which adenocarcinoma prevails. Patients almost invariably develop metastatic drug-resistant disease and this is responsible for our failure to provide curative therapy. Hence, a better understanding of the mechanisms underlying these biological processes is urgently required to improve clinical outcome.The 90-kDa ribosomal S6 kinases (RSKs) are downstream effectors of the RAS/MAPK cascade. RSKs are highly conserved serine/threonine protein kinases implicated in diverse cellular processes, including cell survival, proliferation, migration and invasion. Four isoforms exist in humans (RSK1-4) and are uniquely characterized by the presence of two non-identical N- and C-terminal kinase domains. RSK isoforms are 73-80% identical at protein level and this has been thought to suggest overlapping functions.However, through functional genomic kinome screens, we show that RSK4, contrary to RSK1, promotes both drug resistance and metastasis in lung cancer. This kinase is overexpressed in the majority (57%) of NSCLC biopsies and this correlates with poor overall survival in lung adenocarcinoma patients. Genetic silencing of RSK4 sensitizes lung cancer cells to chemotherapy and prevents their migration and invasiveness in vitro and in vivo. RSK4 downregulation decreases the anti-apoptotic proteins Bcl2 and cIAP1/2 which correlates with increased apoptotic signalling, whilst it also induces mesenchymal-epithelial transition (MET) through inhibition of NFκB activity. A small-molecule inhibitor screen identified several floxacins, including trovafloxacin, as potent allosteric inhibitors of RSK4 activation. Trovafloxacin reproduced all biological and molecular effects of RSK4 silencing in vitro and in vivo, and is predicted to bind a novel allosteric site revealed

Conference paper

Prischi F, Chrysostomou S, Roy R, Chapman K, Mufti U, Peach R, Ding L, Mauri F, Bellezza G, Cagini L, Barbareschi M, Ferrero S, Abrahams J, Ottaviani S, Castellano L, Giamas G, Pascoe J, Moonamale D, Billingham L, Cullen M, Hrouda D, Winkler M, Klug D, Yaliraki S, Barahona M, Wang Y, Ali M, Seckl M, Pardo Oet al., 2019, Targeting RSK4 prevents both chemoresistance and metastasis in lung and bladder cancer, FEBS Open Bio, Publisher: WILEY, Pages: 330-330, ISSN: 2211-5463

Conference paper

Ottaviani S, Castellano L, 2018, microRNAs: novel regulators of the TGF- pathway in pancreatic ductal adenocarcinoma, Molecular & Cellular Oncology, Vol: 5, Pages: 1-3, ISSN: 2372-3556

We identified that transforming growth factor-β (TGF-β) induces long non-coding RNA (lncRNA) MIR100HG along with its host microRNAs (miRNAs) miR-100 and miR-125b, to regulate its response in pancreatic ductal adenocarcinoma (PDAC). Importantly let-7a, despite originating from MIR100HG, remains unchanged because post-transcriptionally repressed by lin-28 homolog B (LIN28B). A novel method for global miRNA-target discovery identified that miR-100/125b regulates crucial PDAC pathways.

Journal article

Ottaviani S, Stebbing J, Frampton AE, Zagorac S, Krell J, de Giorgio A, Trabulo SM, Nguyen VTM, Magnani L, Feng H, Giovannetti E, Funel N, Gress TM, Jiao LR, Lombardo Y, Lemoine NR, Heeschen C, Castellano Let al., 2018, TGF-beta induces miR-100 and miR-125b but blocks let-7a through LIN28B controlling PDAC progression, Nature Communications, Vol: 9, ISSN: 2041-1723

TGF-β/Activin induces epithelial-to-mesenchymal transition and stemness in pancreatic ductal adenocarcinoma (PDAC). However, the microRNAs (miRNAs) regulated during this response have remained yet undetermined. Here, we show that TGF-β transcriptionally induces MIR100HG lncRNA, containing miR-100, miR-125b and let-7a in its intron, via SMAD2/3. Interestingly, we find that although the pro-tumourigenic miR-100 and miR-125b accordingly increase, the amount of anti-tumourigenic let-7a is unchanged, as TGF-β also induces LIN28B inhibiting its maturation. Notably, we demonstrate that inactivation of miR-125b or miR-100 affects the TGF-β-mediated response indicating that these miRNAs are important TGF-β effectors. We integrate AGO2-RIP-seq with RNA-seq to identify the global regulation exerted by these miRNAs in PDAC cells. Transcripts targeted by miR-125b and miR-100 significantly overlap and mainly inhibit p53 and cell–cell junctions’ pathways. Together, we uncover that TGF-β induces an lncRNA, whose encoded miRNAs, miR-100, let-7a and miR-125b play opposing roles in controlling PDAC tumourigenesis.

Journal article

Ali S, Patel H, Periyasamy M, Sava G, Bondke A, Slafer BW, Kroll SHB, Barbazanges MV, Starkey RG, Ottaviani S, Harrod AE, Aboagye EO, Buluwela L, Fuchter MJ, Barrett AGM, Coombes Cet al., 2018, ICEC0942, an orally bioavailable selective inhibitor of CDK7 for cancer treatment, Molecular Cancer Therapeutics, ISSN: 1535-7163

Recent reports indicate that some cancer types are especially sensitive to transcription inhibition, suggesting that targeting the transcriptional machinery provides new approaches to cancer treatment. Cyclin-dependent kinase (CDK)7 is necessary for transcription, and acts by phosphorylating the C-terminal domain (CTD) of RNA polymerase II (PolII) to enable transcription initiation. CDK7 additionally regulates the activities of a number of transcription factors, including Estrogen receptor-α (ER). Here we describe a new, orally bioavailable CDK7 inhibitor, ICEC0942. It selectively inhibits CDK7, with an IC50 of 40nM; IC50 values for CDK1, CDK2, CDK5 and CDK9 were 45-, 15-, 230- and 30-fold higher. In vitro studies show that a wide range of cancer types are sensitive to CDK7 inhibition with GI50 values ranging between 0.2-0.3 µM. In xenografts of both breast and colorectal cancers, the drug has substantial anti-tumor effects. Additionally, combination therapy with tamoxifen showed complete growth arrest of ER-positive tumor xenografts. Our findings reveal that CDK7 inhibition provides a new approach, especially for ER-positive breast cancer and identify ICEC0942 as a prototype drug with potential utility as a single agent or in combination with hormone therapies for breast cancer. ICEC0942 may also be effective in other cancers that display characteristics of transcription factor addiction, such as acute leukaemia, and small-cell lung cancer.

Journal article

Castellano L, Ottaviani S, Frampton AE, 2017, ATGF-beta-lin28b-miRNA Circuit Regulates EMT and Stemness in Pancreatic Cancer, Publisher: LIPPINCOTT WILLIAMS & WILKINS, Pages: 1393-1393, ISSN: 0885-3177

Conference paper

Frampton AE, Miller HC, Malczewska A, Ottaviani S, Stronach EA, Flora R, Kaemmerer D, Schwach G, Pfragner R, Faiz O, Kos-Kudla B, Hanna GB, Stebbing J, Castellano L, Frilling Aet al., 2017, MicroRNAs Associated with Small Bowel Neuroendocrine Tumours and Their Metastases, 14th Annual ENETS Conference for the Diagnosis and Treatment of Neuroendocrine Tumor Disease, Publisher: Karger Publishers, Pages: 22-22, ISSN: 0028-3835

Conference paper

Frampton AE, Ottaviani S, Stebbing J, Jiao LR, Heeschen Cet al., 2017, TGF-Beta Induces miR-100 and miR-125b Promoting EMT and Stemness in Pancreatic Cancer, International Congress of the Association-of-Surgeons-of-Great-Britain-and-Ireland, Publisher: WILEY, Pages: 21-21, ISSN: 0007-1323

Conference paper

Frampton AE, Ottaviani S, Stebbing J, Jiao LR, Castellano Let al., 2017, TGF-Beta Induces miR-100 and miR-125b Promoting EMT and Stemness in Pancreatic Cancer, International Congress of the Association-of-Surgeons-of-Great-Britain-and-Ireland, Publisher: WILEY, Pages: 6-6, ISSN: 0007-1323

Conference paper

Castellano L, Dabrowska A, Pellegrino L, Ottaviani S, Cathcart P, Frampton A, Krell J, Stebbing Jet al., 2017, Sustained expression of miR-26a promotes chromosomal instability and tumorigenesis through regulation of CHFR, Nucleic Acids Research, Vol: 45, Pages: 4401-4412, ISSN: 1362-4962

MicroRNA 26a (miR-26a) reduces cell viability in several cancers, indicating that miR-26a could be used as a therapeutic option in patients. We demonstrate that miR-26a not only inhibits G1-S cell cycle transition and promotes apoptosis, as previously described, but also regulates multiple cell cycle checkpoints. We show that sustained miR-26a over-expression in both breast cancer (BC) cell lines and mouse embryonic fibroblasts (MEFs) induces oversized cells containing either a single-large nucleus or two nuclei, indicating defects in mitosis and cytokinesis. Additionally, we demonstrate that miR-26a induces aneuploidy and centrosome defects and enhances tumorigenesis. Mechanistically, it acts by targeting G1-S transition genes as well as genes involved in mitosis and cytokinesis such as CHFR, LARP1 and YWHAE. Importantly, we show that only the re-expression of CHFR in miR-26a over-expressing cells partially rescues normal mitosis and impairs the tumorigenesis exerted by miR-26a, indicating that CHFR represents an important miR-26a target in the regulation of such phenotypes. We propose that miR-26a delivery might not be a viable therapeutic strategy due to the potential deleterious oncogenic activity of this miRNA.

Journal article

Ali S, Patel H, Periyasamy M, Bondke A, Slafer BW, Ottaviani S, Harrod A, Buluwela L, Fuchter MJ, Barrett AGM, Coombes RCet al., 2016, ICEC0942, an orally bioavailable selective inhibitor of CDK7 for breast cancer, UK Breast Cancer Research Symposium, Publisher: Springer Verlag, Pages: 195-195, ISSN: 0167-6806

Conference paper

Miller HC, Frampton AE, Malczewska A, Ottaviani S, Stronach EA, Flora R, Kaemmerer D, Schwach G, Pfragner R, Faiz O, Kos-Kudła B, Hanna GB, Stebbing J, Castellano L, Frilling Aet al., 2016, MicroRNAs associated with small bowel neuroendocrine tumours and their metastases, Endocrine-Related Cancer, Vol: 23, Pages: 711-726, ISSN: 1479-6821

Novel molecular analytes are needed in small bowel neuroendocrine tumours (SBNETs) to better determine disease aggressiveness and predict treatment response. In this study, we aimed to profile the global miRNome of SBNETs, and identify microRNAs (miRNAs) involved in tumour progression for use as potential biomarkers. Two independent miRNA profiling experiments were performed (n=90), including primary SBNETs (n=28), adjacent normal small bowel (NSB; n=14), matched lymph node (LN) metastases (n=24), normal LNs (n=7), normal liver (n=2) and liver metastases (n=15). We then evaluated potentially targeted genes by performing integrated computational analyses. We discovered 39 miRNAs significantly deregulated in SBNETs compared with adjacent NSB. The most upregulated (miR-204-5p, miR-7-5p and miR-375) were confirmed by qRT-PCR. Two miRNAs (miR-1 and miR-143-3p) were significantly downregulated in LN and liver metastases compared with primary tumours. Furthermore, we identified upregulated gene targets for miR-1 and miR-143-3p in an existing SBNET dataset, which could contribute to disease progression, and show that these miRNAs directly regulate FOSB and NUAK2 oncogenes. Our study represents the largest global miRNA profiling of SBNETs using matched primary tumour and metastatic samples. We revealed novel miRNAs deregulated during SBNET disease progression, and important miRNA–mRNA interactions. These miRNAs have the potential to act as biomarkers for patient stratification and may also be able to guide treatment decisions. Further experiments to define molecular mechanisms and validate these miRNAs in larger tissue cohorts and in biofluids are now warranted.

Journal article

Stebbing J, Frampton AE, Miller HC, Malczewska A, Ottaviani S, Stronach EA, Flora R, Kaemmerer D, Schwach G, Pfragner R, Faiz O, Hanna G, Castellano L, Frilling Aet al., 2016, MicroRNAs associated with small bowel neuroendocrine tumors and their metastases., Annual Meeting of the American-Society-of-Clinical-Oncology (ASCO), Publisher: AMER SOC CLINICAL ONCOLOGY, ISSN: 0732-183X

Conference paper

Lin M-L, Patel H, Remenyi J, Banerji CRS, Lai C-F, Periyasamy M, Lombardo Y, Busonero C, Ottaviani S, Passey A, Quinlan PR, Purdie CA, Jordan LB, Thompson AM, Finn RS, Rueda OM, Caldas C, Gil J, Coombes RC, Fuller-Pace FV, Teschendorff AE, Buluwela L, Ali Set al., 2015, Expression profiling of nuclear receptors in breast cancer identifies TLX as a mediator of growth and invasion in triple-negative breast cancer, Oncotarget, Vol: 6, Pages: 21685-21703, ISSN: 1949-2553

he Nuclear Receptor (NR) superfamily of transcription factors comprises 48 members, several of which have been implicated in breast cancer. Most important is estrogen receptor-α (ERα), which is a key therapeutic target. ERα action is facilitated by co-operativity with other NR and there is evidence that ERα function may be recapitulated by other NRs in ERα-negative breast cancer. In order to examine the inter-relationships between nuclear receptors, and to obtain evidence for previously unsuspected roles for any NRs, we undertook quantitative RT-PCR and bioinformatics analysis to examine their expression in breast cancer. While most NRs were expressed, bioinformatic analyses differentiated tumours into distinct prognostic groups that were validated by analyzing public microarray data sets. Although ERα and progesterone receptor were dominant in distinguishing prognostic groups, other NR strengthened these groups. Clustering analysis identified several family members with potential importance in breast cancer. Specifically, RORγ is identified as being co-expressed with ERα, whilst several NRs are preferentially expressed in ERα-negative disease, with TLX expression being prognostic in this subtype. Functional studies demonstrated the importance of TLX in regulating growth and invasion in ERα-negative breast cancer cells.

Journal article

Cathcart P, Lucchesi W, Ottaviani S, De Giorgio A, Krell J, Stebbing J, Castellano Let al., 2015, Noncoding RNAs and the control of signalling via nuclear receptor regulation in health and disease, BEST PRACTICE & RESEARCH CLINICAL ENDOCRINOLOGY & METABOLISM, Vol: 29, Pages: 529-543, ISSN: 1521-690X

Journal article

Ottaviani S, de Giorgio A, Harding V, Stebbing J, Castellano Let al., 2014, Noncoding RNAs and the control of hormonal signaling via nuclear receptor regulation, JOURNAL OF MOLECULAR ENDOCRINOLOGY, Vol: 53, Pages: R61-R70, ISSN: 0952-5041

Journal article

Krell J, Frampton AE, Mirnezami R, Harding V, De Giorgio A, Alonso LR, Cohen P, Ottaviani S, Colombo T, Jacob J, Pellegrino L, Buchanan G, Stebbing J, Castellano Let al., 2014, Growth Arrest-Specific Transcript 5 Associated snoRNA Levels Are Related to p53 Expression and DNA Damage in Colorectal Cancer, PLOS One, Vol: 9, ISSN: 1932-6203

Background: The growth arrest-specific transcript 5 gene (GAS5) encodes a long noncoding RNA (lncRNA) and hosts anumber of small nucleolar RNAs (snoRNAs) that have recently been implicated in multiple cellular processes and cancer.Here, we investigate the relationship between DNA damage, p53, and the GAS5 snoRNAs to gain further insight into thepotential role of this locus in cell survival and oncogenesis both in vivo and in vitro.Methods: We used quantitative techniques to analyse the effect of DNA damage on GAS5 snoRNA expression and to assessthe relationship between p53 and the GAS5 snoRNAs in cancer cell lines and in normal, pre-malignant, and malignanthuman colorectal tissue and used biological techniques to suggest potential roles for these snoRNAs in the DNA damageresponse.Results: GAS5-derived snoRNA expression was induced by DNA damage in a p53-dependent manner in colorectal cancercell lines and their levels were not affected by DICER. Furthermore, p53 levels strongly correlated with GAS5-derived snoRNAexpression in colorectal tissue.Conclusions: In aggregate, these data suggest that the GAS5-derived snoRNAs are under control of p53 and that they havean important role in mediating the p53 response to DNA damage, which may not relate to their function in the ribosome.We suggest that these snoRNAs are not processed by DICER to form smaller snoRNA-derived RNAs with microRNA (miRNA)-like functions, but their precise role requires further evaluation. Furthermore, since GAS5 host snoRNAs are often used asendogenous controls in qPCR quantifications we show that their use as housekeeping genes in DNA damage experimentscan lead to inaccurate results.

Journal article

Lai C-F, Flach KD, Alexi X, Fox SP, Ottaviani S, Thiruchelvam PTR, Kyle FJ, Thomas RS, Launchbury R, Hua H, Callaghan HB, Carroll JS, Coombes RC, Zwart W, Buluwela L, Ali Set al., 2013, Co-regulated gene expression by oestrogen receptor alpha and liver receptor homolog-1 is a feature of the oestrogen response in breast cancer cells, NUCLEIC ACIDS RESEARCH, Vol: 41, Pages: 10228-10240, ISSN: 0305-1048

Journal article

Ottaviani S, Brooke GN, O'Hanlon-Brown C, Waxman J, Ali S, Buluwela Let al., 2013, Characterisation of the androgen regulation of glycine N-methyltransferase in prostate cancer cells, JOURNAL OF MOLECULAR ENDOCRINOLOGY, Vol: 51, Pages: 301-312, ISSN: 0952-5041

Journal article

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