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Glukhova MA, Hynes N, Vivanco MDM, van Amerongen R, Clarke RB, Bentires-Alj M. The seventh ENBDC workshop on methods in mammary gland development and cancer. Breast Cancer Res 2015; 17:119. [PMID: 26330220 PMCID: PMC4557821 DOI: 10.1186/s13058-015-0629-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Accepted: 08/05/2015] [Indexed: 11/16/2022] Open
Abstract
The seventh annual meeting of the European Network of Breast Development and Cancer Laboratories, held in Weggis, Switzerland, in April 2015, was focused on techniques for the study of normal and cancer stem cells, cell fate decisions, cancer initiation and progression.
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Howell SJ, Alferez D, Spence K, Eyre R, Shaw F, Simoes B, Santiago-Gomez A, Bramley M, Absar M, Saad Z, Chatterjee S, Kirwan C, Gandhi A, Armstrong AC, Wardley AM, Farnie G, Clarke RB. Abstract P2-06-02: Breast cancer stem-like cell activity correlates with tumour progression to metastasis but not with clinical or tumour characteristics. Cancer Res 2015. [DOI: 10.1158/1538-7445.sabcs14-p2-06-02] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Introduction: Breast cancers exhibit cellular heterogeneity, containing both stem-like and more differentiated cells. The activity of cancer stem cells (CSC) is likely to be dependent on the microenvironment or niche. Using 158 patient tumour samples, correlations between niche-independent breast CSC activity and clinical and tumour characteristics were tested.
Methods: 104 early breast cancer surgical samples and 54 unrelated metastatic samples from pleural or ascitic fluid were harvested. To test CSC activity, isolated cells were grown in both primary (formation) and secondary (self-renewal) mammosphere (MS) culture. Tumour initiating activity was also tested by transplanting breast cancer fragments or cells into the sub-cutaneous flanks of NSG mice (n=84 early and n=10 metastatic).
Results: No correlation was found between MS growth, MS formation (%), MS self-renewal (%) or in vivo tumour initiation and breast cancer sub-type, grade, node status or Nottingham prognostic index. 33% of the samples that formed MS in vitro initiated tumours in vivo while only 9% that failed to form MS initiated tumour growth. Metastatic compared to early BC samples grew MS more frequently (53/54 compared to 81/104), and had a higher primary MS formation efficiency (1% vs 0.6%; P<0.001) although rates of MS self-renewal were similar. Tumour initiation in vivo was also more frequent in metastatic than early breast cancer samples (7/10 versus 25/84; P<0.02).
Conclusions: In summary, niche-independent breast CSC activity measured in vitro by MS assay and in vivo by xenograft growth is not directly correlated with standard clinical parameters. However, both in vitro and in vivo CSC activity are increased in metastatic samples. These results suggest that breast CSC activity is independent of other prognostic indicators but may predict for poor outcome tumours. Relapse free survival data are maturing and will be presented with analysis of primary tumour ALDH1 expression.
Citation Format: Sacha J Howell, Denis Alferez, Katherine Spence, Rachel Eyre, Fran Shaw, Bruno Simoes, Angelica Santiago-Gomez, Maria Bramley, Mohamed Absar, Zahida Saad, Sumohan Chatterjee, Cliona Kirwan, Ashu Gandhi, Anne C Armstrong, Andrew M Wardley, Gillian Farnie, Robert B Clarke. Breast cancer stem-like cell activity correlates with tumour progression to metastasis but not with clinical or tumour characteristics [abstract]. In: Proceedings of the Thirty-Seventh Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2014 Dec 9-13; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr P2-06-02.
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Wright PK, Jones SB, Ardern N, Ward R, Clarke RB, Sotgia F, Lisanti MP, Landberg G, Lamb R. 17β-estradiol regulates giant vesicle formation via estrogen receptor-alpha in human breast cancer cells. Oncotarget 2015; 5:3055-65. [PMID: 24931391 PMCID: PMC4102791 DOI: 10.18632/oncotarget.1824] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
A significant proportion of the genes regulated by 17-beta-estradiol (E2) via estrogen receptor alpha (ERα) have roles in vesicle trafficking in breast cancer. Intracellular vesicle trafficking and extracellular vesicles have important roles in tumourigenesis. Here we report the discovery of giant (3-42μm) intracellular and extracellular vesicles (GVs) and the role of E2 on vesicle formation in breast cancer (BC) cell lines using three independent live cell imaging techniques. Large diameter vesicles, GVs were also identified in a patient-derived xenograft BC model, and in invasive breast carcinoma tissue. ERα-positive (MCF-7 and T47D) BC cell lines demonstrated a significant increase in GV formation after stimulation with E2 which was reversed by tamoxifen. ERα-negative (MDA-MB-231 and MDA-MB-468) BC cell lines produced GVs independently of E2 and tamoxifen. These results indicate the existence of both intracellular and extracellular vesicles with considerably larger dimensions than generally recognised with BC cells and suggest that the GVs are regulated by E2 via ERα in ERα-positive BC but by E2-independent mechanisms in ER-ve BC.
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Vieira AF, Ribeiro AS, Dionísio MR, Sousa B, Nobre AR, Albergaria A, Santiago-Gómez A, Mendes N, Gerhard R, Schmitt F, Clarke RB, Paredes J. P-cadherin signals through the laminin receptor α6β4 integrin to induce stem cell and invasive properties in basal-like breast cancer cells. Oncotarget 2015; 5:679-92. [PMID: 24553076 PMCID: PMC3996674 DOI: 10.18632/oncotarget.1459] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
P-cadherin is a classical cell-cell adhesion molecule that, in contrast to E-cadherin, has a positive role in breast cancer progression, being considered a poor prognostic factor in this disease. In previous reports, we have shown that this protein induces cancer stem cell and invasive properties to basal-like breast cancer cells. Here, we clarify the downstream signaling pathways that are triggered by P-cadherin to mediate these effects. We demonstrated that P-cadherin inhibition led to a significant decreased adhesion of cancer cells to the basement membrane substrate laminin, as well as to a major reduction in the expression of the laminin receptor α6β4 integrin. Remarkably, the expression of this heterodimer was required for the invasive capacity and increased mammosphere forming efficiency induced by P-cadherin expression. Moreover, we showed that P-cadherin transcriptionally up-regulates the α6 integrin subunit expression and directly interacts with the β4 integrin subunit. We still showed that P-cadherin downstream signaling, in response to laminin, involves the activation of focal adhesion (FAK), Src and AKT kinases. The association between the expression of P-cadherin, α6β4 heterodimer and the active FAK and Src phosphorylated forms was validated in vivo. Our data establish that there is a crosstalk between P-cadherin and the laminin receptor α6β4 integrin signaling pathway, which link has never been previously described. The activation of this heterodimer explains the stem cell and invasive properties induced by P-cadherin to breast cancer cells, pointing to a new molecular mechanism that may be targeted to counteract the effects induced by this adhesion molecule.
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Singh JK, Simões BM, Howell SJ, Farnie G, Clarke RB. Recent advances reveal IL-8 signaling as a potential key to targeting breast cancer stem cells. Breast Cancer Res 2014; 15:210. [PMID: 24041156 PMCID: PMC3978717 DOI: 10.1186/bcr3436] [Citation(s) in RCA: 179] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Breast cancer stem-like cells (CSCs) are an important therapeutic target as they are purported to be responsible for tumor initiation, maintenance, metastases, and disease recurrence. Interleukin-8 (IL-8) is upregulated in breast cancer compared with normal breast tissue and is associated with poor prognosis. IL-8 is reported to promote breast cancer progression by increasing cell invasion, angiogenesis, and metastases and is upregulated in HER2-positive cancers. Recently, we and others have established that IL-8 via its cognate receptors, CXCR1 and CXCR2, is also involved in regulating breast CSC activity. Our work demonstrates that in metastatic breast CSCs, CXCR1/2 signals via transactivation of HER2. Given the importance of HER2 in breast cancer and in regulating CSC activity, a pathway driving the activation of these receptors would have important biological and clinical consequences, especially in tumors that express high levels of IL-8 and other CXCR1/2-activating ligands. Here, we review the IL-8 signaling pathway and the role of HER2 in maintaining an IL-8 inflammatory loop and discuss the potential of combining CXCR1/2 inhibitors with other treatments such as HER2-targeted therapy as a novel approach to eliminate CSCs and improve patient survival.
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Howell A, Anderson AS, Clarke RB, Duffy SW, Evans DG, Garcia-Closas M, Gescher AJ, Key TJ, Saxton JM, Harvie MN. Risk determination and prevention of breast cancer. Breast Cancer Res 2014; 16:446. [PMID: 25467785 PMCID: PMC4303126 DOI: 10.1186/s13058-014-0446-2] [Citation(s) in RCA: 204] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Breast cancer is an increasing public health problem. Substantial advances have been made in the treatment of breast cancer, but the introduction of methods to predict women at elevated risk and prevent the disease has been less successful. Here, we summarize recent data on newer approaches to risk prediction, available approaches to prevention, how new approaches may be made, and the difficult problem of using what we already know to prevent breast cancer in populations. During 2012, the Breast Cancer Campaign facilitated a series of workshops, each covering a specialty area of breast cancer to identify gaps in our knowledge. The risk-and-prevention panel involved in this exercise was asked to expand and update its report and review recent relevant peer-reviewed literature. The enlarged position paper presented here highlights the key gaps in risk-and-prevention research that were identified, together with recommendations for action. The panel estimated from the relevant literature that potentially 50% of breast cancer could be prevented in the subgroup of women at high and moderate risk of breast cancer by using current chemoprevention (tamoxifen, raloxifene, exemestane, and anastrozole) and that, in all women, lifestyle measures, including weight control, exercise, and moderating alcohol intake, could reduce breast cancer risk by about 30%. Risk may be estimated by standard models potentially with the addition of, for example, mammographic density and appropriate single-nucleotide polymorphisms. This review expands on four areas: (a) the prediction of breast cancer risk, (b) the evidence for the effectiveness of preventive therapy and lifestyle approaches to prevention, (c) how understanding the biology of the breast may lead to new targets for prevention, and (d) a summary of published guidelines for preventive approaches and measures required for their implementation. We hope that efforts to fill these and other gaps will lead to considerable advances in our efforts to predict risk and prevent breast cancer over the next 10 years.
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Clarke RB, Stingl J, Vivanco M, Bentires-Alj M. ‘The charmingest place’: non-coding RNA, lineage tracing, tumor heterogeneity, metastasis and metabolism--new methods in mammary gland development and cancer: the fifth ENBDC Workshop. Breast Cancer Res 2014; 15:313. [PMID: 24103450 PMCID: PMC3979154 DOI: 10.1186/bcr3497] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
The European Network for Breast Development and Cancer (ENBDC) Workshop on ‘Methods in Mammary Gland Development and Cancer’ has grown into the essential, international technical discussion forum for scientists with interests in the normal and neoplastic breast. The fifth ENBDC meeting was held in Weggis, Switzerland in April, 2013, and focussed on emerging, state-of-the-art techniques for the study of non-coding RNA, lineage tracing, tumor heterogeneity, metastasis and metabolism.
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Hidalgo M, Amant F, Biankin AV, Budinská E, Byrne AT, Caldas C, Clarke RB, de Jong S, Jonkers J, Mælandsmo GM, Roman-Roman S, Seoane J, Trusolino L, Villanueva A. Patient-derived xenograft models: an emerging platform for translational cancer research. Cancer Discov 2014; 4:998-1013. [PMID: 25185190 PMCID: PMC4167608 DOI: 10.1158/2159-8290.cd-14-0001] [Citation(s) in RCA: 1168] [Impact Index Per Article: 116.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
UNLABELLED Recently, there has been an increasing interest in the development and characterization of patient-derived tumor xenograft (PDX) models for cancer research. PDX models mostly retain the principal histologic and genetic characteristics of their donor tumor and remain stable across passages. These models have been shown to be predictive of clinical outcomes and are being used for preclinical drug evaluation, biomarker identification, biologic studies, and personalized medicine strategies. This article summarizes the current state of the art in this field, including methodologic issues, available collections, practical applications, challenges and shortcomings, and future directions, and introduces a European consortium of PDX models. SIGNIFICANCE PDX models are increasingly used in translational cancer research. These models are useful for drug screening, biomarker development, and the preclinical evaluation of personalized medicine strategies. This review provides a timely overview of the key characteristics of PDX models and a detailed discussion of future directions in the field.
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Alferez D, Clarke RB, Cresta C, Mnene S, Howell SJ. Abstract P5-05-03: Progesterone receptor antagonists as inhibitors of breast cancer stem cell activity. Cancer Res 2013. [DOI: 10.1158/0008-5472.sabcs13-p5-05-03] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background: Tamoxifen has become the standard of care for premenopausal women with hormone receptor positive breast cancer (BC). However, resistance to Tamoxifen therapy remains a major clinical problem and we have evidence that cancer stem cells (CSCs) may play a role in recurrence in these patients. The progesterone receptor (PR) is a potential therapeutic target in BC but development of steroidal PR antagonists (PRAs) has been halted due to toxicity issues, despite evidence of activity. Recent reports have linked PR activity to the expansion of adult mammary gland stem cells through paracrine effectors such as RANK-L.
Methods: To investigate the effects of PR antagonism on CSCs, we have tested 2 non-steroidal PRAs; onapristone (Schering AG/Arno Therapeutics) and AZPRA (AstraZeneca) in 2 hormone receptor positive BC cell lines (MCF-7 & T47D) and 8 patient-derived samples (PDS; from malignant pleural effusions and ascitic fluid), using a low adherence mammosphere assay. Western and gene expression array analysis of PDS samples were performed to identify predictive biomarkers.
Results: In the presence of 10nM P4 AZPRA inhibited mammosphere forming efficiency (MFE) in MCF-7 cells by 32% (p<0.0001) and in T47D by 21% (p<0.0001). Similar results were seen with onapristone (34% inhibition in MCF-7 (p<0.002) and 34% in T47D cells (p<0.0002). AZPRA or onapristone significantly reduced MFE in 7 of 8 PDS. Tamoxifen affected MFE in 4/6 PDS samples. In 5 of 7 PDS tested additive effects were seen when AZPRA was combined with tamoxifen (>80% reduction in MFE; p<0.001). A similar effect was seen with onapristone (>70% reduction in MFE (p<0.05)). Data from Western analysis of PR A and B isoforms and gene expression analysis of PDS samples will be presented at the conference.
Conclusions: Preliminary data on PR inhibition presented here support the rationale of administration of PRA in the clinic but predictive biomarkers are required to identify which patients are likely to benefit. Combination of PRA with current anti-oestrogen therapies such as Tamoxifen may be a way of overcoming resistance mechanisms by targeting CSCs.
Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P5-05-03.
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Yu L, Liu S, Zhang C, Zhang B, Simões BM, Eyre R, Liang Y, Yan H, Wu Z, Guo W, Clarke RB. Enrichment of human osteosarcoma stem cells based on hTERT transcriptional activity. Oncotarget 2013; 4:2326-38. [PMID: 24334332 PMCID: PMC3926830 DOI: 10.18632/oncotarget.1554] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2013] [Accepted: 11/03/2013] [Indexed: 01/01/2023] Open
Abstract
Telomerase is crucial for the maintenance of stem/progenitor cells in adult tissues and is detected in most malignant cancers, including osteosarcoma. However, the relationship between telomerase expression and cancer stem cells remains unknown. We observed that sphere-derived osteosarcoma cells had higher telomerase activity, indicating that telomerase activity might be enriched in osteosarcoma stem cells. We sorted subpopulations with high or low telomerase activity (TEL) using hTERT transcriptional promoter-induced green fluorescent protein (GFP). The TELpos cells showed an increased sphere and tumor propagating capacity compared to TELneg cells, and enhanced stem cell-like properties such as invasiveness, metastatic activity and resistance to chemotherapeutic agents both in vitro and in vivo. Furthermore, the telomerase inhibitor MST312 prevented tumorigenic potential both in vitro and in vivo, preferentially targeting the TELpos cells. These data support telomerase inhibition as a potential targeted therapy for osteosarcoma stem-like cells.
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Farnie G, Johnson RL, Williams KE, Clarke RB, Bundred NJ. Lapatinib inhibits stem/progenitor proliferation in preclinical in vitro models of ductal carcinoma in situ (DCIS). Cell Cycle 2013; 13:418-25. [PMID: 24247151 DOI: 10.4161/cc.27201] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Breast-conserving surgery for ductal carcinoma in situ (DCIS) is often combined with irradiation, reducing recurrence rates to 20% within 10 years; however, there is no change in overall survival. Evidence in the invasive breast indicates that breast cancer stem cells (CSCs) are radiotherapy-resistant and are capable of re-initiating a tumor recurrence; hence, targeting CSCs in high risk DCIS patient may improve survival. HER2 is overexpressed in 20% of DCIS and is known to be highly active in breast CSCs; we therefore investigated the effect of Lapatinib on DCIS CSC activity using 2 in vitro culture systems. Two DCIS cell lines DCIS.com (HER2 normal) and SUM225 (HER2 overexpressed) as well as DCIS cells from patient samples (n = 18) were cultured as mammospheres to assess CSC activity and in differentiated 3D-matrigel culture to determine effects within the non-CSCs. Mammosphere formation was reduced regardless of HER2 status, although this was more marked within the HER2-positive samples. When grown as differentiated DCIS acini in 3D-matrigel culture, Lapatinib only reduced acini size in the HER2-positive samples via decreased proliferation. Further investigation revealed lapatinib did not reduce self-renewal activity in the CSC population, but their proliferation was decreased regardless of HER2 status. In conclusion we show Lapatinib can reduce DCIS CSC activity, suggesting that the use of Lapatinib in high-risk DCIS patients has the potential to reduce recurrence and the progression of DCIS to invasive disease.
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Eccles SA, Aboagye EO, Ali S, Anderson AS, Armes J, Berditchevski F, Blaydes JP, Brennan K, Brown NJ, Bryant HE, Bundred NJ, Burchell JM, Campbell AM, Carroll JS, Clarke RB, Coles CE, Cook GJR, Cox A, Curtin NJ, Dekker LV, dos Santos Silva I, Duffy SW, Easton DF, Eccles DM, Edwards DR, Edwards J, Evans DG, Fenlon DF, Flanagan JM, Foster C, Gallagher WM, Garcia-Closas M, Gee JMW, Gescher AJ, Goh V, Groves AM, Harvey AJ, Harvie M, Hennessy BT, Hiscox S, Holen I, Howell SJ, Howell A, Hubbard G, Hulbert-Williams N, Hunter MS, Jasani B, Jones LJ, Key TJ, Kirwan CC, Kong A, Kunkler IH, Langdon SP, Leach MO, Mann DJ, Marshall JF, Martin LA, Martin SG, Macdougall JE, Miles DW, Miller WR, Morris JR, Moss SM, Mullan P, Natrajan R, O’Connor JPB, O’Connor R, Palmieri C, Pharoah PDP, Rakha EA, Reed E, Robinson SP, Sahai E, Saxton JM, Schmid P, Smalley MJ, Speirs V, Stein R, Stingl J, Streuli CH, Tutt ANJ, Velikova G, Walker RA, Watson CJ, Williams KJ, Young LS, Thompson AM. Critical research gaps and translational priorities for the successful prevention and treatment of breast cancer. Breast Cancer Res 2013; 15:R92. [PMID: 24286369 PMCID: PMC3907091 DOI: 10.1186/bcr3493] [Citation(s) in RCA: 275] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2013] [Accepted: 09/12/2013] [Indexed: 02/08/2023] Open
Abstract
INTRODUCTION Breast cancer remains a significant scientific, clinical and societal challenge. This gap analysis has reviewed and critically assessed enduring issues and new challenges emerging from recent research, and proposes strategies for translating solutions into practice. METHODS More than 100 internationally recognised specialist breast cancer scientists, clinicians and healthcare professionals collaborated to address nine thematic areas: genetics, epigenetics and epidemiology; molecular pathology and cell biology; hormonal influences and endocrine therapy; imaging, detection and screening; current/novel therapies and biomarkers; drug resistance; metastasis, angiogenesis, circulating tumour cells, cancer 'stem' cells; risk and prevention; living with and managing breast cancer and its treatment. The groups developed summary papers through an iterative process which, following further appraisal from experts and patients, were melded into this summary account. RESULTS The 10 major gaps identified were: (1) understanding the functions and contextual interactions of genetic and epigenetic changes in normal breast development and during malignant transformation; (2) how to implement sustainable lifestyle changes (diet, exercise and weight) and chemopreventive strategies; (3) the need for tailored screening approaches including clinically actionable tests; (4) enhancing knowledge of molecular drivers behind breast cancer subtypes, progression and metastasis; (5) understanding the molecular mechanisms of tumour heterogeneity, dormancy, de novo or acquired resistance and how to target key nodes in these dynamic processes; (6) developing validated markers for chemosensitivity and radiosensitivity; (7) understanding the optimal duration, sequencing and rational combinations of treatment for improved personalised therapy; (8) validating multimodality imaging biomarkers for minimally invasive diagnosis and monitoring of responses in primary and metastatic disease; (9) developing interventions and support to improve the survivorship experience; (10) a continuing need for clinical material for translational research derived from normal breast, blood, primary, relapsed, metastatic and drug-resistant cancers with expert bioinformatics support to maximise its utility. The proposed infrastructural enablers include enhanced resources to support clinically relevant in vitro and in vivo tumour models; improved access to appropriate, fully annotated clinical samples; extended biomarker discovery, validation and standardisation; and facilitated cross-discipline working. CONCLUSIONS With resources to conduct further high-quality targeted research focusing on the gaps identified, increased knowledge translating into improved clinical care should be achievable within five years.
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Singh JK, Simões BM, Clarke RB, Bundred NJ. Targeting IL-8 signalling to inhibit breast cancer stem cell activity. Expert Opin Ther Targets 2013; 17:1235-41. [PMID: 24032691 DOI: 10.1517/14728222.2013.835398] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Although survival from breast cancer has improved significantly over the past 20 years, disease recurrence remains a significant clinical problem. The concept of stem-like cells in cancer has been gaining currency over the last decade or so, since evidence for stem cell activity in human leukaemia and solid tumours, including breast cancer, was first published. Evidence indicates that this sub-population of cells, known as cancer stem-like cells (CSCs), is responsible for driving tumour formation and disease progression. In breast cancer, there is good evidence that CSCs are intrinsically resistant to conventional chemo-, radio- and endocrine therapies. By evading the effects of these treatments, CSCs are held culpable for disease recurrence. Hence, in order to improve treatment there is a need to develop CSC-targeted therapies. Interleukin-8 (IL-8), an inflammatory cytokine, is upregulated in breast cancer and associated with poor prognostic factors. Accumulating evidence demonstrates that IL-8, through its receptors CXCR1/2, is an important regulator of breast CSC activity. Inhibiting CXCR1/2 signalling has proved efficacious in pre-clinical models of breast cancer providing a good rationale for targeting CXCR1/2 clinically. Here, we discuss the role of IL-8 in breast CSC regulation and development of novel therapies to target CXCR1/2 signalling in breast cancer.
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Lamb R, Ablett MP, Spence K, Landberg G, Sims AH, Clarke RB. Wnt pathway activity in breast cancer sub-types and stem-like cells. PLoS One 2013; 8:e67811. [PMID: 23861811 PMCID: PMC3701602 DOI: 10.1371/journal.pone.0067811] [Citation(s) in RCA: 119] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2013] [Accepted: 05/22/2013] [Indexed: 02/06/2023] Open
Abstract
INTRODUCTION Wnt signalling has been implicated in stem cell regulation however its role in breast cancer stem cell regulation remains unclear. METHODS We used a panel of normal and breast cancer cell lines to assess Wnt pathway gene and protein expression, and for the investigation of Wnt signalling within stem cell-enriched populations, mRNA and protein expression was analysed after the selection of anoikis-resistant cells. Finally, cell lines and patient-derived samples were used to investigate Wnt pathway effects on stem cell activity in vitro. RESULTS Wnt pathway signalling increased in cancer compared to normal breast and in both cell lines and patient samples, expression of Wnt pathway genes correlated with estrogen receptor (ER) expression. Furthermore, specific Wnt pathway genes were predictive for recurrence within subtypes of breast cancer. Canonical Wnt pathway genes were increased in breast cancer stem cell-enriched populations in comparison to normal breast stem cell-enriched populations. Furthermore in cell lines, the ligand Wnt3a increased whilst the inhibitor DKK1 reduced mammosphere formation with the greatest inhibitory effects observed in ER+ve breast cancer cell lines. In patient-derived metastatic breast cancer samples, only ER-ve mammospheres were responsive to the ligand Wnt3a. However, the inhibitor DKK1 efficiently inhibited both ER+ve and ER-ve breast cancer but not normal mammosphere formation, suggesting that the Wnt pathway is aberrantly activated in breast cancer mammospheres. CONCLUSIONS Collectively, these data highlight differential Wnt signalling in breast cancer subtypes and activity in patient-derived metastatic cancer stem-like cells indicating a potential for Wnt-targeted treatment in breast cancers.
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MESH Headings
- Breast Neoplasms/genetics
- Breast Neoplasms/metabolism
- Breast Neoplasms/pathology
- Carcinoma, Ductal, Breast/genetics
- Carcinoma, Ductal, Breast/metabolism
- Carcinoma, Ductal, Breast/pathology
- Carcinoma, Lobular/genetics
- Carcinoma, Lobular/metabolism
- Carcinoma, Lobular/pathology
- Cell Line, Tumor
- Female
- Gene Expression Profiling
- Gene Expression Regulation, Neoplastic
- Humans
- Intercellular Signaling Peptides and Proteins/genetics
- Intercellular Signaling Peptides and Proteins/metabolism
- Neoplasm Metastasis
- Neoplastic Stem Cells/metabolism
- Neoplastic Stem Cells/pathology
- Organ Specificity
- Receptors, Estrogen/genetics
- Receptors, Estrogen/metabolism
- Signal Transduction
- Wnt3A Protein/genetics
- Wnt3A Protein/metabolism
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Lamb R, Lehn S, Rogerson L, Clarke RB, Landberg G. Cell cycle regulators cyclin D1 and CDK4/6 have estrogen receptor-dependent divergent functions in breast cancer migration and stem cell-like activity. Cell Cycle 2013; 12:2384-94. [PMID: 23839043 DOI: 10.4161/cc.25403] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Cyclin D1 and its binding partners CDK4/6 are essential regulators of cell cycle progression and are implicated in cancer progression. Our aim was to investigate a potential regulatory role of these proteins in other essential tumor biological characteristics. Using a panel of breast cancer cell lines and primary human breast cancer samples, we have demonstrated the importance of these cell cycle regulators in both migration and stem-like cell activity. siRNA was used to target cyclin D1 and CDK4/6 expression, having opposing effects on both migration and stem-like cell activity dependent upon estrogen receptor (ER) expression. Inhibition of cyclin D1 or CDK4/6 increases or decreases migration and stem-like cell activity in ER-ve (ER-negative) and ER+ve (ER-positive) breast cancer, respectively. Furthermore, overexpressed cyclin D1 caused decreased migration and stem-like cell activity in ER-ve cells while increasing activity in ER+ve breast cancer cells. Treatment of breast cancer cells with inhibitors of cyclin D1 and CDK4/6 (Flavopiridol/PD0332991), currently in clinical trials, mimicked the effects observed with siRNA treatment. Re-expression of ER in two ER-ve cell lines was sufficient to overcome the effects of either siRNA or clinical inhibitors of cyclin D1 and CDK4/6. In conclusion, cyclin D1 and CDK4/6 have alternate roles in regulation of migration and stem-like cell activity. Furthermore, these effects are highly dependent upon expression of ER. The significance of these results adds to our general understanding of cancer biology but, most importantly, could be used diagnostically to predict treatment response to cell cycle inhibition in breast cancer.
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McClements L, Yakkundi A, Papaspyropoulos A, Harrison H, Ablett MP, Jithesh PV, McKeen HD, Bennett R, Donley C, Kissenpfennig A, McIntosh S, McCarthy HO, O'Neill E, Clarke RB, Robson T. Targeting treatment-resistant breast cancer stem cells with FKBPL and its peptide derivative, AD-01, via the CD44 pathway. Clin Cancer Res 2013; 19:3881-93. [PMID: 23741069 DOI: 10.1158/1078-0432.ccr-13-0595] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
PURPOSE FK506-binding protein like (FKBPL) and its peptide derivative, AD-01, have already shown tumor growth inhibition and CD44-dependent antiangiogenic activity. Here, we explore the ability of AD-01 to target CD44-positive breast cancer stem cells (BCSC). EXPERIMENTAL DESIGN Mammosphere assays and flow cytometry were used to analyze the effect of FKBPL overexpression/knockdown and AD-01 treatment ± other anticancer agents on BCSCs using breast cancer cell lines (MCF-7/MDA-231/ZR-75), primary patient samples, and xenografts. Delays in tumor initiation were evaluated in vivo. The anti-stem cell mechanisms were determined using clonogenic assays, quantitative PCR (qPCR), and immunofluorescence. RESULTS AD-01 treatment was highly effective at inhibiting the BCSC population by reducing mammosphere-forming efficiency and ESA(+)/CD44(+)/CD24(-) or aldehyde dehydrogenase (ALDH)(+) cell subpopulations in vitro and tumor initiation in vivo. The ability of AD-01 to inhibit the self-renewal capacity of BCSCs was confirmed; mammospheres were completely eradicated by the third generation. The mechanism seems to be due to AD-01-mediated BCSC differentiation shown by a significant decrease in the number of holoclones and an associated increase in meroclones/paraclones; the stem cell markers, Nanog, Oct4, and Sox2, were also significantly reduced. Furthermore, we showed additive inhibitory effects when AD-01 was combined with the Notch inhibitor, DAPT. AD-01 was also able to abrogate a chemo- and radiotherapy-induced enrichment in BCSCs. Finally, FKBPL knockdown led to an increase in Nanog/Oct4/Sox2 and an increase in BCSCs, highlighting a role for endogenous FKBPL in stem cell signaling. CONCLUSIONS AD-01 has dual antiangiogenic and anti-BCSC activity, which will be advantageous as this agent enters clinical trial.
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Harrison H, Simões BM, Rogerson L, Howell SJ, Landberg G, Clarke RB. Oestrogen increases the activity of oestrogen receptor negative breast cancer stem cells through paracrine EGFR and Notch signalling. Breast Cancer Res 2013; 15:R21. [PMID: 23497505 PMCID: PMC3672803 DOI: 10.1186/bcr3396] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2012] [Accepted: 03/05/2013] [Indexed: 12/18/2022] Open
Abstract
Introduction Although oestrogen is essential for the development of the normal breast, adult mammary stem cells are known to be oestrogen receptor alpha (ER) negative and rely on paracrine signals in the mammary epithelium for mediation of developmental cues. However, little is known about how systemic oestrogen regulates breast cancer stem cell (CSC) activity. Methods Here, we tested the effects of oestrogen on CSC activity in vitro and in vivo and investigated which paracrine signalling pathways locally mediate oestrogen effects. Results CSC-enriched populations (ESA+CD44+CD24low) sorted from ER positive patient derived and established cell lines have low or absent ER expression. However, oestrogen stimulated CSC activity demonstrated by increased mammosphere and holoclone formation in vitro and tumour formation in vivo. This effect was abrogated by the anti-oestrogen tamoxifen or ER siRNA. These data suggest that the oestrogen response is mediated through paracrine signalling from non-CSCs to CSCs. We have, therefore, investigated both epidermal growth factor (EGF) and Notch receptor signals downstream of oestrogen. We demonstrate that gefitinib (epidermal growth factor receptor (EGFR) inhibitor) and gamma secretase inhibitors (Notch inhibitor) block oestrogen-induced CSC activity in vitro and in vivo but GSIs more efficiently reduce CSC frequency. Conclusions These data establish that EGF and Notch receptor signalling pathways operate downstream of oestrogen in the regulation of ER negative CSCs.
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Farnie G, Willan PM, Clarke RB, Bundred NJ. Combined inhibition of ErbB1/2 and Notch receptors effectively targets breast ductal carcinoma in situ (DCIS) stem/progenitor cell activity regardless of ErbB2 status. PLoS One 2013; 8:e56840. [PMID: 23457626 PMCID: PMC3572946 DOI: 10.1371/journal.pone.0056840] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2012] [Accepted: 01/15/2013] [Indexed: 01/08/2023] Open
Abstract
Pathways involved in DCIS stem and progenitor signalling are poorly understood yet are critical to understand DCIS biology and to develop new therapies. Notch and ErbB1/2 receptor signalling cross talk has been demonstrated in invasive breast cancer, but their role in DCIS stem and progenitor cells has not been investigated. We have utilised 2 DCIS cell lines, MCF10DCIS.com (ErbB2-normal) and SUM225 (ErbB2-overexpressing) and 7 human primary DCIS samples were cultured in 3D matrigel and as mammospheres in the presence, absence or combination of the Notch inhibitor, DAPT, and ErbB1/2 inhibitors, lapatinib or gefitinib. Western blotting was applied to assess downstream signalling. In this study we demonstrate that DAPT reduced acini size and mammosphere formation in MCF10DCIS.com whereas there was no effect in SUM225. Lapatinb reduced acini size and mammosphere formation in SUM225, whereas mammosphere formation and Notch1 activity were increased in MCF10DCIS.com. Combined DAPT/lapatinib treatment was more effective at reducing acini size in both DCIS cell lines. Mammosphere formation in cell lines and human primary DCIS was reduced further by DAPT/lapatinib or DAPT/gefitinib regardless of ErbB2 receptor status. Our pre-clinical human models of DCIS demonstrate that Notch and ErbB1/2 both play a role in DCIS acini growth and stem cell activity. We report for the first time that cross talk between the two pathways in DCIS occurs regardless of ErbB2 receptor status and inhibition of Notch and ErbB1/2 was more efficacious than either alone. These data provide further understanding of DCIS biology and suggest treatment strategies combining Notch and ErbB1/2 inhibitors should be investigated regardless of ErbB2 receptor status.
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Brennan K, Clarke RB. Combining Notch inhibition with current therapies for breast cancer treatment. Ther Adv Med Oncol 2013; 5:17-24. [PMID: 23323144 DOI: 10.1177/1758834012457437] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Over recent years, there has been an increasing interest in targeting Notch signalling for the treatment of breast cancer. This has stemmed from the realization that many Notch pathway components display altered expression in breast cancer, and that Notch signalling impacts on many of the cellular properties associated with tumour initiation and progression. Consequently, Notch pathway inhibitors are now entering the initial stages of clinical trials. However, there is a definite need to consider how best to use these inhibitors and therefore which treatment strategies are likely to yield the most promising results. In particular, recent studies suggest that the greatest success will come from combining Notch pathway inhibitors with current breast cancer therapies.
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Harrison H, Rogerson L, Gregson HJ, Brennan KR, Clarke RB, Landberg G. Contrasting Hypoxic Effects on Breast Cancer Stem Cell Hierarchy Is Dependent on ER-α Status. Cancer Res 2012; 73:1420-33. [DOI: 10.1158/0008-5472.can-12-2505] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Singh JK, Farnie G, Bundred NJ, Simões BM, Shergill A, Landberg G, Howell SJ, Clarke RB. Targeting CXCR1/2 significantly reduces breast cancer stem cell activity and increases the efficacy of inhibiting HER2 via HER2-dependent and -independent mechanisms. Clin Cancer Res 2012; 19:643-56. [PMID: 23149820 DOI: 10.1158/1078-0432.ccr-12-1063] [Citation(s) in RCA: 170] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
PURPOSE Breast cancer stem-like cells (CSC) are an important therapeutic target as they are predicted to be responsible for tumor initiation, maintenance, and metastases. Interleukin (IL)-8 is upregulated in breast cancer and is associated with poor prognosis. Breast cancer cell line studies indicate that IL-8 via its cognate receptors, CXCR1 and CXCR2, is important in regulating breast CSC activity. We investigated the role of IL-8 in the regulation of CSC activity using patient-derived breast cancers and determined the potential benefit of combining CXCR1/2 inhibition with HER2-targeted therapy. EXPERIMENTAL DESIGN CSC activity of metastatic and invasive human breast cancers (n = 19) was assessed ex vivo using the mammosphere colony-forming assay. RESULTS Metastatic fluid IL-8 level correlated directly with mammosphere formation (r = 0.652; P < 0.05; n = 10). Recombinant IL-8 directly increased mammosphere formation/self-renewal in metastatic and invasive breast cancers (n = 17). IL-8 induced activation of EGFR/HER2 and downstream signaling pathways and effects were abrogated by inhibition of SRC, EGFR/HER2, phosphoinositide 3-kinase (PI3K), or MEK. Furthermore, lapatinib, which targets EGFR/HER2, inhibited the mammosphere-promoting effect of IL-8 in both HER2-positive and negative patient-derived cancers. CXCR1/2 inhibition also blocked the effect of IL-8 on mammosphere formation and added to the efficacy of lapatinib in HER2-positive cancers. CONCLUSIONS These studies establish a role for IL-8 in the regulation of patient-derived breast CSC activity and show that IL-8/CXCR1/2 signaling is partly mediated via a novel SRC and EGFR/HER2-dependent pathway. Combining CXCR1/2 inhibitors with current HER2-targeted therapies has potential as an effective therapeutic strategy to reduce CSC activity in breast cancer and improve the survival of HER2-positive patients.
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Shaw FL, Harrison H, Spence K, Ablett MP, Simões BM, Farnie G, Clarke RB. A detailed mammosphere assay protocol for the quantification of breast stem cell activity. J Mammary Gland Biol Neoplasia 2012; 17:111-7. [PMID: 22665270 DOI: 10.1007/s10911-012-9255-3] [Citation(s) in RCA: 254] [Impact Index Per Article: 21.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/12/2012] [Accepted: 05/07/2012] [Indexed: 01/05/2023] Open
Abstract
Since the discovery that neural tissue contains a population of stem cells that form neurospheres in vitro, sphere-forming assays have been adapted for use with a number of different tissue types for the quantification of stem cell activity and self-renewal. One tissue type widely used for stem cell investigations is mammary tissue, and the mammosphere assay has been used in both normal tissue and cancer. Although it is a relatively simple assay to learn, it can be difficult to master. There are methodological and analytical aspects to the assay which require careful consideration when interpreting the results. We describe here a detailed mammosphere assay protocol for the assessment of stem cell activity and self-renewal, and discuss how data generated by the assay can be analysed and interpreted.
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Vieira AF, Ricardo S, Ablett MP, Dionísio MR, Mendes N, Albergaria A, Farnie G, Gerhard R, Cameselle-Teijeiro JF, Seruca R, Schmitt F, Clarke RB, Paredes J. P-Cadherin Is Coexpressed with CD44 and CD49f and Mediates Stem Cell Properties in Basal-like Breast Cancer. Stem Cells 2012; 30:854-64. [DOI: 10.1002/stem.1075] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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Ferraldeschi R, Latif A, Clarke RB, Spence K, Ashton G, O’Sullivan J, Evans DG, Howell A, Newman WG. Lack of caveolin-1 (P132L) somatic mutations in breast cancer. Breast Cancer Res Treat 2012; 132:1185-6. [DOI: 10.1007/s10549-012-1981-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2012] [Accepted: 01/27/2012] [Indexed: 10/14/2022]
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Singh JK, Farnie G, Clarke RB, Bundred NJ. P3-17-04: CXCR1/2 Regulates Human Breast Cancer Stem Cell Activity Via EGFR/HER2−Dependent and -Independent Pathway. Cancer Res 2011. [DOI: 10.1158/0008-5472.sabcs11-p3-17-04] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background
Increasing evidence suggests that breast cancers are sustained by breast cancer stem cells (CSCs). Interleukin-8 (IL-8) via its cognate receptors, CXCR1 and CXCR2, and HER2 regulate CSC activity. Cytokine receptors can trans-activate members of the epidermal growth factor receptor (EGFR) family in normal and malignant tissue. The aims of this study were to determine (1) the effect of the IL-8-CXCR1/2 signalling pathway on human breast CSC activity, (2) the effect of CXCR1/2 inhibition in combination with EGFR/HER-2 inhibition on CSC activity and (3) the interaction of CXCR1/2 and EGFR/HER2 in breast cancer.
Methods: Human breast cancer cell lines used were HER2−18 and SKBR3 (both HER2 over-expressing). Primary human breast cancer cells were extracted from metastatic samples (pleural effusion n=4; ascites n=5; local recurrence n=1) and invasive breast cancers (n=1). CSC activity was investigated in vitro using the mammosphere assay. Mammosphere forming efficiency (MFE) was determined by dividing the number of mammospheres >60μm in diameter divided by the number of cells seeded and expressed as a percentage. Data is represented as mean MFE ± standard error of mean normalised to control. Statistical significance (P) was determined using Mann-Whitney U test (2-tailed). Inhibitors used were SCH563705 (a CXCR1/2 inhibitor; 100nM), Lapatinib (an EGFR/HER-2 inhibitor; 1–10μM) and Gefitinib (an EGFR inhibitor; 1μM).
Results: IL-8 (100ng/ml) increased HER2−18 mean MFE from 1±0.05% to 1.20±0.04%; 19.5% increase; P=0.0061. This effect was reduced by SCH563705 (from 1.20±0.04% to 0.70±0.05; 41.7% reduction; P=0.0001) and Lapatinib (from 1.20±0.04% to 0.51±0.04; 57.5% reduction; P <0.0001). Combination treatment resulted in a greater reduction in mean MFE compared to either SCH563705 (P<0.0001) or Lapatinib (P=0.026).
IL-8 (100ng/ml) increased mean MFE of primary human breast cancer cells from 1±0.03% to 1.43±0.06%; 42.9% increase; P<0.0001 (n=11 patient samples). This effect was reduced by SCH563705 from 1.43±0.06% to 0.96±0.04%; 32.9% reduction; P<0.0001. In HER2 over-expressing patient samples (n=4), IL-8-induced increase in MFE was reduced by SCH563705 (from 1.43±0.06% to 0.83±0.05; 42.0% reduction; P<0.0001) and Lapatinib (from 1.43±0.06% to 0.91±0.05%; 36.4% reduction; P<0.0001). Combination treatment resulted in a greater reduction in mean MFE compared to either SCH563705 (P=0.0019) or Lapatinib (P<0.0001). In HER2−non-over-expressing samples (n=6), IL-8-induced increase in MFE was reduced by SCH563705 (from 1.45±0.10% to 1.06±0.05; 27.0% decrease; P=0.0005) and Lapatinib (from 1.45±0.10% to 1.15±0.07%; 20.7% decrease; P=0.0145). Combination treatment had no additional effect. Western blot analysis of the HER2−18 and SKBR3 cell lines showed that IL-8 induced phosphorylation of HER-2, AKT and MAPK within 10 minutes; these effects were inhibited by Lapatinib and Gefitinib.
Conclusions: IL-8/CXCR1/2 regulates the activity of human breast CSCs. Lapatinib inhibited IL-8 signalling suggesting that CXCR1/2 signal transduction involves an EGFR/HER2−dependent pathway. Targeting CXCR1/2 adds to the efficacy of targeting HER2 in HER2−over-expressing human breast CSCs through inhibition of an EGFR/HER2−independent pathway.
Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P3-17-04.
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