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Li Z, Song Y, Hou W, Qi Y, Lu X, Xue Y, Huang J, Fang Q. Atractylodin induces oxidative stress-mediated apoptosis and autophagy in human breast cancer MCF-7 cells through inhibition of the P13K/Akt/mTOR pathway. J Biochem Mol Toxicol 2022; 36:e23081. [PMID: 35478473 DOI: 10.1002/jbt.23081] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Revised: 01/29/2022] [Accepted: 04/01/2022] [Indexed: 11/06/2022]
Abstract
This study aimed to determine the apoptosis and autophagy-inducing mechanism of atractylodin in human breast cancer MCF-7 cells. The molecular mechanism of anticancer activity of atractylodin was confirmed by assessing the levels of reactive oxygen species (ROS) level, lipid peroxidation (LPO), antioxidants activity, dual staining, and comet assay. Moreover, cleaved caspases 3, 8, and 9, and signaling proteins, such as p53, Bcl-2, and Bax, phosphatidylinositol-3-kinase/protein kinase B/mammalian target of rapamycin(P13K/Akt/mTOR), LC3I and LC3II, and beclin-1 were analyzed. In MCF-7 cells treated with atractylodin, the concentration-dependent toxicity, increased LPO, increased production of ROS, and decreased activity of superoxide dismutase, catalase, and glutathione peroxidasewere observed. In MCF-7 cells, atractylodin administration decreased Bcl-2 expression while activating the expression of p53, Bax, cleaved caspase-3, caspase-8, and caspase-9 apoptotic members. Furthermore, atractylodin blocked the P13K/Akt/mTOR signaling pathway, increased the conversion of LC3I to its lipidated form of LC3II, and increased beclin-1 expression, whereas downregulated the p62 expression in MCF-7 cells. As a result, altering apoptotic and autophagy-related biomarkers, atractylodin triggered apoptosis and autophagy in MCF-7 cells. As a result, atractylodin could be utilized to treat human breast cancer after the proper clinical trial.
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Affiliation(s)
- Zuowei Li
- First Clinical Medical College, Shandong University of Traditional Chinese Medicine, Jinan, Shandong, China.,Department of Encephalopathy, Affiliated Hospital of Shandong University of Traditional Chinese Medicine, Jinan, Shandong, China
| | - YeLin Song
- Ward 1 of Cardiovascular Medicine, Qingdao Hospital of Tradiational Chinese Medicine, Qingdao, Shandong, China
| | - Wangjun Hou
- First Clinical Medical College, Shandong University of Traditional Chinese Medicine, Jinan, Shandong, China
| | - Yingzi Qi
- College of Health, Shandong University of Traditional Chinese Medicine, Jinan, Shandong, China
| | - Xuxiang Lu
- Department of Internal Medicine, Shandong University of Traditional Chinese Medicine, Jinan, Shandong, China
| | - Ye Xue
- First Clinical Medical College, Shandong University of Traditional Chinese Medicine, Jinan, Shandong, China
| | - Jie Huang
- First Clinical Medical College, Shandong University of Traditional Chinese Medicine, Jinan, Shandong, China
| | - Qiong Fang
- College of Traditional Chinese Medicine, Shandong University of Traditional Chinese Medicine, Jinan, Shandong, China
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Parthenolide inhibits tumor-promoting effects of nicotine in lung cancer by inducing P53 - dependent apoptosis and inhibiting VEGF expression. Biomed Pharmacother 2018; 107:1488-1495. [DOI: 10.1016/j.biopha.2018.08.139] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Revised: 08/24/2018] [Accepted: 08/25/2018] [Indexed: 12/21/2022] Open
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Hou GX, Liu P, Yang J, Wen S. Mining expression and prognosis of topoisomerase isoforms in non-small-cell lung cancer by using Oncomine and Kaplan-Meier plotter. PLoS One 2017; 12:e0174515. [PMID: 28355294 PMCID: PMC5371362 DOI: 10.1371/journal.pone.0174515] [Citation(s) in RCA: 132] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Accepted: 03/10/2017] [Indexed: 01/09/2023] Open
Abstract
DNA topoisomerases are essential to modulate DNA topology during various cellular genetic processes. The expression and distinct prognostic value of topoisomerase isoforms in non-small-cell lung cancer (NSCLC) is not well established. In the current study, we have examined the mRNA expression of topoisomerase isoforms by using Oncomine analysis and investigated their prognostic value via the Kaplan–Meier plotter database in NSCLC patients. Our analysis indicated that the expression level of topoisomerases in lung cancer was higher compared with normal tissues. Especially, high expression of two topoisomerase isoforms, TOP2A and TOP3A, was found to be correlated to worse overall survival (OS) in all NSCLC and lung adenocarcinoma (Ade) patients, but not in lung squamous cell carcinoma (SCC) patients. In a contrast, high expression of isoforms TOP1 and TOP2B indicated better OS in all NSCLC and Ade, but not in SCC patients. Meanwhile, high expression of TOP1MT and TOP3B was not correlated with OS in NSCLC patients. Furthermore, we also demonstrated a relationship between topoisomerase isoforms and the clinicopathological features for the NSCLC patients, such as grades, clinical stages, lymph node status, smoking status, gender, chemotherapy and radiotherapy. These results support that TOP2A and TOP3A are associated with worse prognosis in NSCLC patients. In addition, our study also shows that TOP1 and TOP2B contribute to favorable prognosis in NSCLC patients. The exact prognostic significance of TOP1MT and TOP3B need to be further elucidated. Comprehensive evaluation of expression and prognosis of topoisomerase isoforms will be a benefit for the better understanding of heterogeneity and complexity in the molecular biology of NSCLC, paving a way for more accurate prediction of prognosis and discovery of potential drug targets for NSCLC patients.
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Affiliation(s)
- Guo-Xin Hou
- Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in Southern China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, China
| | - Panpan Liu
- Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in Southern China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, China
| | - Jing Yang
- Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in Southern China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, China
| | - Shijun Wen
- Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in Southern China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, China
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, China
- * E-mail:
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Wu F, Zhou L, Jin W, Yang W, Wang Y, Yan B, Du W, Zhang Q, Zhang L, Guo Y, Zhang J, Shan L, Efferth T. Anti-Proliferative and Apoptosis-Inducing Effect of Theabrownin against Non-small Cell Lung Adenocarcinoma A549 Cells. Front Pharmacol 2016; 7:465. [PMID: 27994550 PMCID: PMC5133245 DOI: 10.3389/fphar.2016.00465] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Accepted: 11/16/2016] [Indexed: 12/22/2022] Open
Abstract
With the highest cancer incidence rate, lung cancer, especially non-small cell lung cancer (NSCLC), is the leading cause of cancer death in the world. Tea (leaves of Camellia sinensis) has been widely used as a traditional beverage beneficial to human health, including anti-NSCLC activity. Theabrownin (TB) is one major kind of tea pigment responsible for the beneficial effects of tea liquor. However, its effect on NSCLC is unknown. The aim of the present study was to evaluate anti-proliferative and apoptosis-inducing effect of TB on NSCLC (A549) cells, using MTT assay, morphological observation (DAPI staining), in situ terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay, and annexin-V/PI flow cytometry. Subsequently, the expression of several genes associated with cell proliferation and apoptosis were detected by real time PCR assay to explore its potential underlying mechanism. TB was revealed to inhibit cell proliferation of A549 cells in a concentration-dependent and time-dependent manner. Morphological observation, TUNEL assay and flow cytometric analysis evidenced an apoptosis-inducing effect of TB on A549 cells in a concentration-dependent manner. The real time PCR assay demonstrated that TB down-regulated the expression of TOPO I, TOPO II, and BCL-2, and up-regulated the expression of E2F1, P53, GADD45, BAX, BIM, and CASP 3,7,8,9, which suggests an activation of P53-mediated apoptotic (caspase-dependent) pathway in response to TB treatment. The western blot analysis showed a similar trend for the corresponding protein expression (P53, Bax, Bcl-2, caspase 3,9, and PARP) and further revealed DNA damage as a trigger of the apoptosis (phosphorylation of histone H2A.X). Accordingly, TB can be speculated as a DNA damage inducer and topoisomerase (Topo I and Topo II) inhibitor that can up-regulate P53 expression and subsequently modulate the expression of the downstream genes to induce cell proliferation inhibition and apoptosis of A549 cells. Our results indicate that TB exhibits its anti-NSCLC activity via a P53-dependent mechanism, which may be a promising candidate of natural product for anti-cancer drug development in the treatment of NSCLC.
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Affiliation(s)
- Feifei Wu
- Institute for Cell-Based Drug Development of Zhejiang Province, S-Evans Biosciences, Ltd.Hangzhou, China
| | - Li Zhou
- Institute of Orthopaedics and Traumatology, Zhejiang Chinese Medical UniversityHangzhou, China
| | - Wangdong Jin
- Institute of Orthopaedics and Traumatology, Zhejiang Chinese Medical UniversityHangzhou, China
| | - Weiji Yang
- Institute of Orthopaedics and Traumatology, Zhejiang Chinese Medical UniversityHangzhou, China
| | - Ying Wang
- Institute of Orthopaedics and Traumatology, Zhejiang Chinese Medical UniversityHangzhou, China
| | - Bo Yan
- Institute of Orthopaedics and Traumatology, Zhejiang Chinese Medical UniversityHangzhou, China
| | - Wenlin Du
- Institute for Cell-Based Drug Development of Zhejiang Province, S-Evans Biosciences, Ltd.Hangzhou, China
| | - Qiang Zhang
- Institute for Cell-Based Drug Development of Zhejiang Province, S-Evans Biosciences, Ltd.Hangzhou, China
| | - Lei Zhang
- School of Medicine, Zhejiang UniversityHangzhou, China
| | - Yonghua Guo
- Institute for Cell-Based Drug Development of Zhejiang Province, S-Evans Biosciences, Ltd.Hangzhou, China
| | | | - Letian Shan
- Institute of Orthopaedics and Traumatology, Zhejiang Chinese Medical UniversityHangzhou, China
| | - Thomas Efferth
- Department of Pharmaceutical Biology, Institute of Pharmacy and Biochemistry, Johannes Gutenberg UniversityMainz, Germany
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B1, a novel topoisomerase II inhibitor, induces apoptosis and cell cycle G1 arrest in lung adenocarcinoma A549 cells. Anticancer Drugs 2012; 23:191-9. [PMID: 22008852 DOI: 10.1097/cad.0b013e32834cd277] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
In our previous studies, we demonstrated that 2,6-bis-(2-chloroacetamido) anthraquinone (B1) showed a highly significant cytotoxic effect. However, its influence in the cell cycle and apoptotic induction effects has not been investigated yet. Here we report the antiproliferative effect of B1, for which IC50 values were 0.57 μmol/l for lung cancer A549 cells, 0.63 μmol/l for colon cancer HT-29 cells, and 0.53 μmol/l for breast cancer MCF-7 cells. DNA topoisomerase II (Topo II), an essential enzyme in DNA synthesis and meiotic division, is highly expressed in cancer cells. Some currently used clinical anticancer drugs (doxorubicin and mitoxantrone) targeting Topo II are very effective antineoplastic agents. B1, sharing the basic structure of known Topo II inhibitors, demonstrated a significant inhibitory effect on Topo II bioactivity. In A549 cells, B1 increased apoptotic cell population with induction of Fas, Bax, and cleaved poly(ADP-ribose) polymerase and by reduction of Bcl-2 expression. Moreover, cell cycle analysis indicated that B1 induced G1 phase arrest through modulation of G1 cell cycle regulatory proteins, such as the downregulation of cyclin D1 and upregulation of Cip/p21, Kip1/p27, and p53. Thus, our study suggests that B1, with the ability to inhibit Topo II activity and cause cell cycle G1 arrest and apoptosis, has potential as a novel anticancer agent.
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Nakanishi F, Ohkawa K, Ishida H, Hosui A, Sato A, Hiramatsu N, Ueda K, Takehara T, Kasahara A, Sasaki Y, Hori M, Hayashi N. Alteration in gene expression profile by full-length hepatitis B virus genome. Intervirology 2005; 48:77-83. [PMID: 15812178 DOI: 10.1159/000081732] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2003] [Accepted: 02/13/2004] [Indexed: 11/19/2022] Open
Abstract
Persistent expression of hepatitis B virus (HBV) proteins is thought to be involved in virus-related hepatocarcinogenesis. Here, we compared the gene expression profile of cells persistently expressing the full-length HBV with that of negative control cells to comprehensively investigate virus-mediated changes in the gene expression of the host cells. RNA samples from both virus-expressing and negative control cells were used for the DNA array assay. DNA array assay and subsequent corroboration assays revealed that expression of 14 of 1,176 genes (1.2%) was altered in response to virus expression. The upregulated genes included CD44, high mobility group protein-I, thymosin beta-10 and 27-kD heat shock protein, while the downregulated genes included NM23-H1, all of which are thought to be associated with the development or progression of carcinoma in the liver or other organs. Furthermore, virus expression resulted in the decrease of two apoptosis-inducing molecules, caspase-3 and BAX, which may also contribute to carcinogenesis through prolonged survival of the host cell. Thus, expression of the virus genome caused carcinogenesis-related changes in host cell gene expression. HBV expression may change the host cell to a malignant phenotype through alterations in the expression levels of a set of genes.
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Affiliation(s)
- Fumihiko Nakanishi
- Department of Internal Medicine and Therapeutic, Osaka University Graduate School of Medicine, Suita, Osaka, Japan
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Potter AJ, Rabinovitch PS. The cell cycle phases of DNA damage and repair initiated by topoisomerase II-targeting chemotherapeutic drugs. Mutat Res 2005; 572:27-44. [PMID: 15790488 DOI: 10.1016/j.mrfmmm.2004.11.018] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2004] [Revised: 11/09/2004] [Accepted: 11/22/2004] [Indexed: 10/25/2022]
Abstract
Although cytostasis and cytotoxicity induced by cancer chemotherapy drugs targeting topoisomerase II (topoII) arise in specific cell cycle phases, it is unknown whether the drug-initiated DNA damage triggering these responses, or the repair (reversal) of this damage, differs between cell cycle phases or between drug classes. Accordingly, we used a flow cytometric alkaline unwinding assay to measure DNA damage (strand breakage (SB)) and SB repair in each cell cycle compartment of human cancer cell lines treated with clinically relevant concentrations of doxorubicin, daunomycin, etoposide, and mitoxantrone. We found that treated HeLa and A549 cells exhibited the greatest SB in G2/M phase, the least in G1 phase, and generally an intermediate amount in S phase. The cell cycle phase specificity of the DNA damage appeared to be predictive of the cell cycle phase of growth arrest. Furthermore, it appeared to be dependent on topoIIalpha expression as the extent of SB did not differ between cell cycle compartments in topoIIalpha-diminished A549(VP)28 cells. HeLa cells were apparently unable to repair doxorubicin-initiated SB. The rate of repair of etoposide-initiated SB in HeLa cells and of mitoxantrone-initiated SB in HeLa and A549 cells was similar in each cell cycle compartment. In A549 cells, the rate of repair of doxorubicin and etoposide-initiated SB differed between cell cycle phases. Overall, these results indicate that the cell cycle phase specificity of cytostasis and cytotoxicity induced in tumor cells by topoII-targeting drugs may be directly related to the cell cycle phase specificity of the drug-initiated DNA damage. Analysis by cell cycle compartment appears to clarify some of the intercellular heterogeneity in the extent of drug-initiated DNA damage and cytotoxicity previously observed in cancer cells analyzed as a single population; this approach might be useful in resolving inconsistent results reported in investigations of tumor cell topoII content versus response to topoII-targeting drugs.
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Affiliation(s)
- Alan J Potter
- Department of Pathology, Box 357705, University of Washington, Seattle, WA 98195, USA
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Lemke K, Poindessous V, Skladanowski A, Larsen AK. The antitumor triazoloacridone C-1305 is a topoisomerase II poison with unusual properties. Mol Pharmacol 2004; 66:1035-42. [PMID: 15258255 DOI: 10.1124/mol.104.000703] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
C-1305 [S-[[3-(dimethylamino)propyl]amino]-8-hydroxy-6H-v-triazolo[4,5,1-de]acridin-6-one] is a triazoloacridone with excellent activity in colon cancer models. The mechanism of C-1305 is unknown, although similarities in the chemical structure between C-1305 and amsacrine suggest common cellular targets. Here, we report that C-1305 is a topoisomerase II poison that is able to induce cleavable complexes with topoisomerase II in vitro as well as in living cells. Even at optimal concentrations, C-1305 is a much weaker inducer of cleavable complexes than amsacrine. Because the cytotoxic activities of the two compounds after continuous drug exposure are comparable, these findings suggest that the low levels of cleavable complexes induced by C-1305 may be unusually toxic. In contrast to amsacrine, the cytotoxicity of C-1305 is strongly time-dependent, with at least 24 h of drug exposure required for optimal cytotoxicity. The p53 tumor suppressor is inactivated in the majority of human tumors, including colorectal cancers. We therefore compared the long-term cytotoxic effects of C-1305, amsacrine, and doxorubicin on human cell lines in which the p53 or p21 pathways have been specifically disrupted by targeted homologous recombination. Disruption of p53 and p21 had minor influence on the cytotoxicity of doxorubicin, whereas p53 but not p21 disruption was associated with increased resistance to amsacrine. In marked contrast, disruption of p53 and p21 was associated with increased sensitivity to C-1305. Taken together, our results show that exposure to C-1305 is accompanied by the formation of low levels of potent cleavable complexes that are selectively toxic toward tumor cells with defective p53 function.
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Affiliation(s)
- Krzysztof Lemke
- Laboratory of Biology and Pharmacogenetics of Human Tumors, Centre National de la Recherche Scientifique Unité Mixte Recherche 8113, Ecole Normale Supérieure Cachan, France
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Kobayashi K, Nishioka M, Kohno T, Nakamoto M, Maeshima A, Aoyagi K, Sasaki H, Takenoshita S, Sugimura H, Yokota J. Identification of genes whose expression is upregulated in lung adenocarcinoma cells in comparison with type II alveolar cells and bronchiolar epithelial cells in vivo. Oncogene 2004; 23:3089-96. [PMID: 14755238 DOI: 10.1038/sj.onc.1207433] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
To identify genes whose expression is upregulated in lung adenocarcinoma (AdC) cells in comparison with noncancerous peripheral lung epithelial cells, type II alveolar cells and bronchiolar epithelial cells, as well as AdC cells, were isolated by laser capture microdissection, and subjected to cDNA microarray analysis of 637 human cancer-related genes. Each of the component cells was obtained from several different individuals and analysed independently. As a comparison, two lung AdC cell lines and two primarily cultured normal lung epithelial cell lines were also subjected to cDNA microarray analysis. Four genes, TOP2A, MMP15, MX2 and KOC1, were commonly upregulated in microdissected AdC cells in comparison with microdissected epithelial cells. Hierarchical clustering analysis revealed that differences in gene-expression profiles were more evident between cultured and uncultured cells than between cancerous and noncancerous cells. To further identify the common molecular targets of AdC cells in vivo, quantitative real-time RT-PCR was performed against the four genes upregulated by cDNA microarray analysis. The TOP2A, MMP15, MX2 and KOC1 genes were overexpressed in 10/10 (100%), 8/10 (80%), 5/10 (50%) and 3/10 (30%) microdissected AdC cell samples, respectively, in comparison with any of nine independently microdissected noncancerous epithelial cell samples. The TOP2A gene was commonly overexpressed in lung AdC cells, as previously reported. In addition, the MMP15 and MX2 genes were identified, for the first time, as being commonly overexpressed in lung AdC cells. These results strongly indicate that the MMP15 and MX2 genes could be novel markers for molecular diagnosis and therapy of lung AdC.
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Affiliation(s)
- Keiko Kobayashi
- Biology Division, National Cancer Center Research Institute, 1-1 Tsukiji 5-chome, Chuo-ku, Tokyo 104-0045, Japan
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Berney DM, Shamash J, Gaffney J, Jordan S, Oliver RTD. DNA topoisomerase I and II expression in drug resistant germ cell tumours. Br J Cancer 2002; 87:624-9. [PMID: 12237772 PMCID: PMC2364243 DOI: 10.1038/sj.bjc.6600472] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2002] [Revised: 05/21/2002] [Accepted: 05/23/2002] [Indexed: 12/02/2022] Open
Abstract
A small number of testicular germ cell tumours are refractory to current chemotherapy regimens. DNA topoisomerase I is the target for several new drugs and a potential candidate treatment for chemorefractory germ cell tumours. DNA topoisomerase II alpha is the target for etoposide, which is currently used regularly in germ cell tumour treatment. The expression of DNA topoisomerase I and II alpha were therefore assessed immunohistochemically in a range of testicular tumours, especially those with persistent malignant elements on retroperitoneal lymph node dissection. Pre-chemotherapy orchidectomy specimens were matched with post-chemotherapy retroperitoneal lymph node dissections to examine changes in expression. There was considerable variation in the expression of topoisomerase I in different tumour types. Both yolk sac tumours and teratoma, mature showed universal expression of topoisomerase I, while 38% of seminomas and 30% of embryonal carcinomas were positive. Strong topoisomerase II alpha expression was found in embryonal carcinoma. There was a negative correlation between topoisomerase I and II alpha expression (P=0.004) and downregulation of topoisomerase II alpha after chemotherapy (P=0.02). Topoisomerase I expression appears to increase in those cases with residual teratoma, mature, but is largely unchanged in those cases remaining as embryonal carcinoma. These results suggest that topoisomerase I inhibitors may be useful in chemorefractory germ cell tumours, especially yolk sac tumours and where there are unresectable residual teratoma, mature deposits.
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Affiliation(s)
- D M Berney
- Department of Histopathology and Morbid Anatomy, St Bartholomew's Hospital, Queen Mary's School of Medicine and Dentistry, London EC1 7BE, UK.
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