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Castagnoli L, Ghedini GC, Koschorke A, Triulzi T, Dugo M, Gasparini P, Casalini P, Palladini A, Iezzi M, Lamolinara A, Lollini PL, Nanni P, Chiodoni C, Tagliabue E, Pupa SM. Pathobiological implications of the d16HER2 splice variant for stemness and aggressiveness of HER2-positive breast cancer. Oncogene 2016; 36:1721-1732. [PMID: 27641338 PMCID: PMC5447867 DOI: 10.1038/onc.2016.338] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Accepted: 08/05/2016] [Indexed: 12/21/2022]
Abstract
We have previously shown that the d16HER2 splice variant is linked to HER2-positive
breast cancer (BC) tumorigenesis, progression and response to Trastuzumab. However,
the mechanisms by which d16HER2 contributes to HER2-driven aggressiveness and
targeted therapy susceptibility remain uncertain. Here, we report that the
d16HER2-positive mammary tumor cell lines MI6 and MI7, derived from spontaneous
lesions of d16HER2 transgenic (tg) mice and resembling the aggressive features of
primary lesions, are enriched in the expression of Wnt, Notch and
epithelial–mesenchymal transition pathways related genes compared with
full-length wild-type (WT) HER2-positive cells (WTHER2_1 and WTHER2_2) derived from
spontaneous tumors arising in WTHER2 tg mice. MI6 cells exhibited increased
resistance to anoikis and significantly higher mammosphere-forming efficiency (MFE)
and self-renewal capability than the WTHER2-positive counterpart. Furthermore,
d16HER2-positive tumor cells expressed a higher fraction of
CD29High/CD24+/SCA1Low cells and
displayed greater in vivo tumor engraftment in serial dilution conditions
than WTHER2_1 cells. Accordingly, NOTCH inhibitors impaired mammosphere formation
only in MI6 cells. A comparative analysis of stemness-related features driven by
d16HER2 and WTHER2 in ad hoc engineered human BC cells (MCF7 and T47D)
revealed a higher MFE and aldehyde dehydrogenase-positive staining in d16HER2- vs
WTHER2-infected cells, sustaining consistent BC-initiating cell enrichment in the
human setting. Moreover, marked CD44 expression was found in MCF7_d16 and T47D_d16
cells vs their WTHER2 and Mock counterparts. Clinically, BC cases from two distinct
HER2-positive cohorts characterized by high levels of expression of the
activated-d16HER2 metagene were significantly enriched in the Notch family and signal
transducer genes vs those with low levels of the metagene.
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Affiliation(s)
- L Castagnoli
- Molecular Targeting Unit, Department of Experimental Oncology and Molecular Medicine, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy
| | - G C Ghedini
- Molecular Targeting Unit, Department of Experimental Oncology and Molecular Medicine, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy
| | - A Koschorke
- Molecular Targeting Unit, Department of Experimental Oncology and Molecular Medicine, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy
| | - T Triulzi
- Molecular Targeting Unit, Department of Experimental Oncology and Molecular Medicine, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy
| | - M Dugo
- Functional Genomics and Bioinformatics Core Facility, Department of Experimental Oncology and Molecular Medicine, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy
| | - P Gasparini
- Tumor Genomics Unit, Department of Experimental Oncology and Molecular Medicine, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy
| | - P Casalini
- Molecular Targeting Unit, Department of Experimental Oncology and Molecular Medicine, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy
| | - A Palladini
- Laboratory of Immunology and Biology of Metastases, Department of Experimental, Diagnostic and Specialty Medicine, University of Bologna, Bologna, Italy
| | - M Iezzi
- CESI Aging Research Center, Department of Medicine and Aging Sciences, G D'Annunzio University, Via Colle dell'Ara, Chieti Scalo, Chieti, Italy
| | - A Lamolinara
- CESI Aging Research Center, Department of Medicine and Aging Sciences, G D'Annunzio University, Via Colle dell'Ara, Chieti Scalo, Chieti, Italy
| | - P L Lollini
- Laboratory of Immunology and Biology of Metastases, Department of Experimental, Diagnostic and Specialty Medicine, University of Bologna, Bologna, Italy
| | - P Nanni
- Laboratory of Immunology and Biology of Metastases, Department of Experimental, Diagnostic and Specialty Medicine, University of Bologna, Bologna, Italy
| | - C Chiodoni
- Molecular Immunology Unit, Department of Experimental Oncology and Molecular Medicine, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy
| | - E Tagliabue
- Molecular Targeting Unit, Department of Experimental Oncology and Molecular Medicine, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy
| | - S M Pupa
- Molecular Targeting Unit, Department of Experimental Oncology and Molecular Medicine, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy
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Stivarou T, Stellas D, Vartzi G, Thomaidou D, Patsavoudi E. Targeting highly expressed extracellular HSP90 in breast cancer stem cells inhibits tumor growth in vitro and in vivo. Cancer Biol Ther 2016; 17:799-812. [PMID: 27259689 DOI: 10.1080/15384047.2016.1195041] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Breast cancer stem cells (BCSC) have been identified in breast carcinoma as CD44(+)/CD24(-/low) cells, which display tumorigenic activity and have the ability to self-renew, differentiate and metastasize. Previous studies showed that extracellular HSP90 (eHSP90) participates in the invasion and metastatic processes of various cancers including breast cancer. Here, we show for the first time that eHSP90 is over-expressed in mammosphere cultures that are derived from the MDA-MB-231, MDA-MB-453 and MCF-7 breast cancer cell lines. These mammospheres are highly enriched in cells of the CD44(+)/CD24(-/low) BCSC phenotype and additionally show high expression of the BCSC markers CD49f and Sox2. Thus our results indicate that eHSP90 represents a potential novel BCSC marker. Moreover, we present evidence that eHSP90 is functionally involved in BCSC activity in vitro and in vivo. Selective neutralization of eHSP90, using the monoclonal antibody mAb 4C5, has the capacity to inhibit stem cell activity in vitro because the formation of mammosphere-derived colonies is dramatically reduced in its presence. In vivo, the treatment of mice with mAb4C5 using a prophylactic protocol, significantly inhibited the primary growth of MDA-MB-231 and mammosphere-derived tumors. More importantly, administration of this antibody in a therapeutic protocol caused a statistically significant regression of established tumors derived from MDA-MB-231 originating mammospheres. Tumor regression was even greater when mAb 4C5 was administered in combination with paclitaxel. Overall, our findings implicate eHSP90 as a potential novel BCSC biomarker. Moreover they show that eHSP90 participates in BCSC-derived primary tumor growth. Finally, we provide additional support for the possible therapeutic value of mAb4C5 in the treatment of breast cancer.
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Affiliation(s)
- Theodora Stivarou
- a Department of Biomedical Engineering and Technology , Technological Educational Institute of Athens , Athens Greece.,b Department of Biochemistry , Hellenic Pasteur Institute , Athens , Greece
| | - Dimitris Stellas
- c Department of Cancer Biology of the Biomedical Research Foundation of the Academy of Athens , Athens Greece
| | - Georgia Vartzi
- b Department of Biochemistry , Hellenic Pasteur Institute , Athens , Greece
| | - Dimitra Thomaidou
- b Department of Biochemistry , Hellenic Pasteur Institute , Athens , Greece
| | - Evangelia Patsavoudi
- a Department of Biomedical Engineering and Technology , Technological Educational Institute of Athens , Athens Greece.,b Department of Biochemistry , Hellenic Pasteur Institute , Athens , Greece
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Over-expression of NOTCH1 as a biomarker for invasive breast ductal carcinoma. 3 Biotech 2016; 6:58. [PMID: 28330128 PMCID: PMC4752955 DOI: 10.1007/s13205-016-0373-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Accepted: 09/10/2015] [Indexed: 12/17/2022] Open
Abstract
Breast cancer is the leading cause of cancer-related death in women worldwide. Invasive ductal carcinoma (IDC) is the most frequent invasive form of breast cancer followed by metastasis. There is no accepted marker for distinguishing this form from other less aggressive forms of breast cancer. Therefore, finding new markers especially molecularly detectable ones are noteworthy. It has been shown that NOTCH1 has been overexpressed in the patients with breast cancer, but no study has investigated the expression of NOTCH1 and its correlation with other molecular and hormonal markers of breast cancer so far. In the current study, 20 breast cancer tissues and 20 matched adjacent normal breast tissue from breast cancer patients were obtained and categorized in two groups: patients with IDC and patient with other types of breast cancer. Gene expression analysis using real-time PCR showed that the NOTCH1 gene was significantly overexpressed in patients with IDC. We also found a slight correlation between NOTCH1 overexpression and p53 accumulation in the cancerous cells confirmed by Immunohistochemistry (IHC). This results showed that it is possible to introduce NOTCH1 expression as a novel biomarker of IDC, alone or preferably accompanied by IHC of p53. We also can design new therapeutic agents targeting NOTCH1 expression for inhibition of metastasis in ductal breast carcinoma.
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Lian C, Ruan L, Shang D, Wu Y, Lu Y, Lü P, Yang Y, Wei Y, Dong X, Ren D, Chen K, Liu H, Tu Z. Heparin-Binding Epidermal Growth Factor-Like Growth Factor as a Potent Target for Breast Cancer Therapy. Cancer Biother Radiopharm 2016; 31:85-90. [DOI: 10.1089/cbr.2015.1956] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Affiliation(s)
- Caixia Lian
- Institute of Life Sciences, Jiangsu University, Zhenjiang, China
| | - Lingling Ruan
- School of Pharmacy, Jiangsu University, Zhenjiang, China
| | - Dongsheng Shang
- Institute of Life Sciences, Jiangsu University, Zhenjiang, China
| | - Yanfang Wu
- Institute of Life Sciences, Jiangsu University, Zhenjiang, China
| | - Yongjin Lu
- School of Pharmacy, Jiangsu University, Zhenjiang, China
| | - Peng Lü
- Institute of Life Sciences, Jiangsu University, Zhenjiang, China
| | - Yuhua Yang
- School of Pharmacy, Jiangsu University, Zhenjiang, China
| | - Yajun Wei
- School of Pharmacy, Jiangsu University, Zhenjiang, China
| | - Xiaojing Dong
- School of Pharmacy, Jiangsu University, Zhenjiang, China
| | - Dewan Ren
- School of Pharmacy, Jiangsu University, Zhenjiang, China
| | - Keping Chen
- Institute of Life Sciences, Jiangsu University, Zhenjiang, China
| | - Hanqing Liu
- School of Pharmacy, Jiangsu University, Zhenjiang, China
| | - Zhigang Tu
- Institute of Life Sciences, Jiangsu University, Zhenjiang, China
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Gollamudi J, Parvani JG, Schiemann WP, Vinayak S. Neoadjuvant therapy for early-stage breast cancer: the clinical utility of pertuzumab. Cancer Manag Res 2016; 8:21-31. [PMID: 26937204 PMCID: PMC4762586 DOI: 10.2147/cmar.s55279] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Approximately 20% of breast cancer patients harbor tumors that overexpress human epidermal growth factor receptor 2 (HER2; also known as ErbB2), a receptor tyrosine kinase that belongs to the epidermal growth factor receptor family of receptor tyrosine kinases. HER2 amplification and hyperactivation drive the growth and survival of breast cancers through the aberrant activation of proto-oncogenic signaling systems, particularly the Ras/MAP kinase and PI3K/AKT pathways. Although HER2-positive (HER2(+)) breast cancer was originally considered to be a highly aggressive form of the disease, the clinical landscape of HER2(+) breast cancers has literally been transformed by the approval of anti-HER2 agents for adjuvant and neoadjuvant settings. Indeed, pertuzumab is a novel monoclonal antibody that functions as an anti-HER2 agent by targeting the extracellular dimerization domain of the HER2 receptor; it is also the first drug to receive an accelerated approval by the US Food and Drug Administration for use in neoadjuvant settings in early-stage HER2(+) breast cancer. Here, we review the molecular and cellular factors that contribute to the pathophysiology of HER2 in breast cancer, as well as summarize the landmark preclinical and clinical findings underlying the approval and use of pertuzumab in the neoadjuvant setting. Finally, the molecular mechanisms operant in mediating resistance to anti-HER2 agents, and perhaps to pertuzumab as well, will be discussed, as will the anticipated clinical impact and future directions of pertuzumab in breast cancer patients.
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Affiliation(s)
- Jahnavi Gollamudi
- Department of Internal Medicine, Case Western Reserve University, Cleveland, OH, USA
| | - Jenny G Parvani
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA
| | - William P Schiemann
- Case Comprehensive Cancer Center, Case Western Reserve University, Cleveland, OH, USA
| | - Shaveta Vinayak
- Case Comprehensive Cancer Center, Case Western Reserve University, Cleveland, OH, USA
- Department of Hematology and Oncology, University Hospitals Case Medical Center, Cleveland, OH, USA
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56
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Witzel I, Oliveira-Ferrer L, Pantel K, Müller V, Wikman H. Breast cancer brain metastases: biology and new clinical perspectives. Breast Cancer Res 2016; 18:8. [PMID: 26781299 PMCID: PMC4717619 DOI: 10.1186/s13058-015-0665-1] [Citation(s) in RCA: 190] [Impact Index Per Article: 23.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Because of improvements in the treatment of patients with metastatic breast cancer, the development of brain metastases (BM) has become a major limitation of life expectancy and quality of life for many breast cancer patients. The improvement of management strategies for BM is thus an important clinical challenge, especially among high-risk patients such as human epidermal growth factor receptor 2-positive and triple-negative patients. However, the formation of BM as a multistep process is thus far poorly understood. To grow in the brain, single tumor cells must pass through the tight blood–brain barrier (BBB). The BBB represents an obstacle for circulating tumor cells entering the brain, but it also plays a protective role against immune cell and toxic agents once metastatic cells have colonized the cerebral compartment. Furthermore, animal studies have shown that, after passing the BBB, the tumor cells not only require close contact with endothelial cells but also interact closely with many different brain residential cells. Thus, in addition to a genetic predisposition of the tumor cells, cellular adaptation processes within the new microenvironment may also determine the ability of a tumor cell to metastasize. In this review, we summarize the biology of breast cancer that has spread into the brain and discuss the implications for current and potential future treatment strategies.
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Affiliation(s)
- Isabell Witzel
- Department of Gynecology, University Medical Center Hamburg-Eppendorf, Martinistraße 52, 20246, Hamburg, Germany.
| | - Leticia Oliveira-Ferrer
- Department of Gynecology, University Medical Center Hamburg-Eppendorf, Martinistraße 52, 20246, Hamburg, Germany.
| | - Klaus Pantel
- Institute of Tumour Biology, University Medical Center Hamburg-Eppendorf, Center of Experimental Medicine, Martinistraße 52, 20246, Hamburg, Germany.
| | - Volkmar Müller
- Department of Gynecology, University Medical Center Hamburg-Eppendorf, Martinistraße 52, 20246, Hamburg, Germany.
| | - Harriet Wikman
- Institute of Tumour Biology, University Medical Center Hamburg-Eppendorf, Center of Experimental Medicine, Martinistraße 52, 20246, Hamburg, Germany.
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Duncombe TA, Kang CC, Maity S, Ward TM, Pegram MD, Murthy N, Herr AE. Hydrogel Pore-Size Modulation for Enhanced Single-Cell Western Blotting. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2016; 28:327-334. [PMID: 26567472 PMCID: PMC4708057 DOI: 10.1002/adma.201503939] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2015] [Revised: 10/05/2015] [Indexed: 05/18/2023]
Abstract
Pore-gradient microgel arrays enable thousands of parallel high-resolution single-cell protein electrophoresis separations for targets accross a wide molecular mass (25-289 kDa), yet within 1 mm separation distances. Dual crosslinked hydrogels facilitate gel-pore expansion after electrophoresis for efficient and uniform immunoprobing. The photopatterned, light-activated, and acid-expandable hydrogel underpins single-cell protein analysis, here for oncoprotein-related signaling in human breast biopsy.
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Affiliation(s)
- Todd A. Duncombe
- Department of Bioengineering, University of California Berkeley, Berkeley, California, CA 94720, USA
- The UC Berkeley/UCSF Graduate Program in Bioengineering, University of California Berkeley, Berkeley, California, CA 94720, USA
| | - Chi-Chih Kang
- Department of Bioengineering, University of California Berkeley, Berkeley, California, CA 94720, USA
| | - Santanu Maity
- Department of Bioengineering, University of California Berkeley, Berkeley, California, CA 94720, USA
| | - Toby M. Ward
- Division of Oncology, Department of Medicine, Stanford University, Stanford, California, CA 94305, USA
| | - Mark D. Pegram
- Division of Oncology, Department of Medicine, Stanford University, Stanford, California, CA 94305, USA
| | - Niren Murthy
- Department of Bioengineering, University of California Berkeley, Berkeley, California, CA 94720, USA
- The UC Berkeley/UCSF Graduate Program in Bioengineering, University of California Berkeley, Berkeley, California, CA 94720, USA
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Palazzo E, Morandi P, Lotti R, Saltari A, Truzzi F, Schnebert S, Dumas M, Marconi A, Pincelli C. Notch Cooperates with Survivin to Maintain Stemness and to Stimulate Proliferation in Human Keratinocytes during Ageing. Int J Mol Sci 2015; 16:26291-302. [PMID: 26540052 PMCID: PMC4661807 DOI: 10.3390/ijms161125948] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Revised: 10/09/2015] [Accepted: 10/22/2015] [Indexed: 01/01/2023] Open
Abstract
The Notch signaling pathway orchestrates cell fate by either inducing cell differentiation or maintaining cells in an undifferentiated state. This study aims to evaluate Notch expression and function in normal human keratinocytes. Notch1 is expressed in all epidermal layers, though to a different degree of intensity, with a dramatic decrease during ageing. Notch1 intracellular domain (N1ICD) levels are decreased during transit from keratinocyte stem cells (KSC) to transit amplifying (TA) cells, mimicking survivin expression in samples from donors of all ages. Calcium markedly reduces N1ICD levels in keratinocytes. N1ICD overexpression induces the up-regulation of survivin and the down-regulation of keratin 10 and involucrin, while increasing the S phase of the cell cycle. On the other hand, Notch1 inhibition (DAPT) dose-dependently decreases survivin, stimulates differentiation, and reduces keratinocyte proliferation in samples from donors of all ages. Silencing Notch downgrades survivin and increases keratin 10. In addition, Notch1 inhibition decreases survivin levels and proliferation both in KSC and TA cells. Finally, while survivin overexpression decreases keratinocyte differentiation and increases N1ICD expression both in KSC and TA cells, silencing survivin results in N1ICD down-regulation and an increase in differentiation markers. These results suggest that the Notch1/survivin crosstalk contributes to the maintenance of stemness in human keratinocytes.
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Affiliation(s)
- Elisabetta Palazzo
- Laboratory of Cutaneous Biology, Department of Surgical, Medical, Dental and Morphological Sciences, University of Modena and Reggio Emilia, via del Pozzo 71, Modena 41121, Italy.
| | - Paolo Morandi
- Laboratory of Cutaneous Biology, Department of Surgical, Medical, Dental and Morphological Sciences, University of Modena and Reggio Emilia, via del Pozzo 71, Modena 41121, Italy.
| | - Roberta Lotti
- Laboratory of Cutaneous Biology, Department of Surgical, Medical, Dental and Morphological Sciences, University of Modena and Reggio Emilia, via del Pozzo 71, Modena 41121, Italy.
| | - Annalisa Saltari
- Laboratory of Cutaneous Biology, Department of Surgical, Medical, Dental and Morphological Sciences, University of Modena and Reggio Emilia, via del Pozzo 71, Modena 41121, Italy.
| | - Francesca Truzzi
- Laboratory of Cutaneous Biology, Department of Surgical, Medical, Dental and Morphological Sciences, University of Modena and Reggio Emilia, via del Pozzo 71, Modena 41121, Italy.
| | | | - Marc Dumas
- LVMH Recherche, 185 Avenue de Verdun, Saint Jean de Braye 45800, France.
| | - Alessandra Marconi
- Laboratory of Cutaneous Biology, Department of Surgical, Medical, Dental and Morphological Sciences, University of Modena and Reggio Emilia, via del Pozzo 71, Modena 41121, Italy.
| | - Carlo Pincelli
- Laboratory of Cutaneous Biology, Department of Surgical, Medical, Dental and Morphological Sciences, University of Modena and Reggio Emilia, via del Pozzo 71, Modena 41121, Italy.
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Epidermal growth factor receptor status and Notch inhibition in non-small cell lung cancer cells. J Biomed Sci 2015; 22:98. [PMID: 26497899 PMCID: PMC4619334 DOI: 10.1186/s12929-015-0196-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Accepted: 10/06/2015] [Indexed: 01/03/2023] Open
Abstract
BACKGROUND Notch may behave as an oncogene or a tumor suppressor gene in lung cancer cells. Notch receptor undergoes cleavage by enzymes, including γ-secretase, generating the active Notch intracellular domain (NICD). The aim of the present study was to investigate the effect of DAPT, a γ-secretase inhibitor, in non-small cell lung cancer (NSCLC) cells, as well as the impact of epidermal growth factor (EGF) that is over-expressed by NSCLC cells, on Notch signaling. H23, A549, H661 and HCC827 human NSCLC cell lines were used, expressing various NICD and EGF receptor (EGFR) protein levels. RESULTS DAPT decreased the number of H661 cells in a concentration-dependent manner, while it had a small effect on H23 and A549 cells and no effect on HCC827 cells that carry mutated EGFR. Notch inhibition did not affect the stimulatory effect of EGF on cell proliferation, while EGF prevented DAPT-induced NICD decrease in H23 and H661 cells. The type of cell death induced by DAPT seems to depend on the cell type. CONCLUSIONS Our data indicate that inhibition of Notch cleavage may not affect cell number in the presence of EGFR mutations and that EGFR may affect Notch signalling suggesting that a dual inhibition of these pathways might be promising in NSCLC.
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