Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitor Reverses Mesenchymal to Epithelial Phenotype and Inhibits Metastasis in Inflammatory Breast Cancer
ABSTRACT Inflammatory breast cancer (IBC) is a rare but aggressive type of advanced breast cancer. Epidermal growth factor receptor (EGFR) expression is an independent poor prognostic factor in IBC. The purpose of this study was to determine the effect on IBC tumorigenicity and metastasis of blocking the EGFR pathway.
IBC cell lines, which express high level of EGFR, were treated with EGFR small interfering RNA and with the EGFR tyrosine kinase inhibitor erlotinib. The role of EGFR in IBC cell proliferation, motility, invasiveness, and change of the expression levels of epithelial-mesenchymal transition markers was examined. The role of extracellular signal-regulated kinase (ERK)-1/2 in erlotinib activity was also studied. The activity of erlotinib in tumor growth and metastasis was examined in an orthotopic xenograft model of IBC.
Erlotinib inhibited proliferation and anchorage-independent growth of IBC cells, and this inhibition was ERK dependent. Erlotinib inhibited cell motility and invasiveness and reversed the mesenchymal phenotype of IBC cells to epithelial phenotype in three-dimensional culture. Erlotinib dramatically inhibited IBC tumor growth in a xenograft model. Interestingly, erlotinib inhibited spontaneous lung metastasis, even at a low dose that had no significant effect on primary tumor growth. These erlotinib-treated tumors were converted to epithelial phenotype from mesenchymal phenotype.
The EGFR pathway is involved in tumor growth and metastasis of IBC. Targeting EGFR through the ERK pathway may represent an effective therapeutic approach to suppress tumorigenicity and prevent metastasis in EGFR-expressing IBC.
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ABSTRACT: Parenteral and oral routes have been the traditional methods of administering cytotoxic agents to cancer patients. Unfortunately, the maximum potential effect of these cytotoxic agents has been limited because of systemic toxicity and poor tumor perfusion. In an attempt to improve the efficacy of cytotoxic agents while mitigating their side effects, we have developed modalities for the localized iontophoretic delivery of cytotoxic agents. These iontophoretic devices were designed to be implanted proximal to the tumor with external control of power and drug flow. Three distinct orthotopic mouse models of cancer and a canine model were evaluated for device efficacy and toxicity. Orthotopic patient-derived pancreatic cancer xenografts treated biweekly with gemcitabine via the device for 7 weeks experienced a mean log2 fold change in tumor volume of -0.8 compared to a mean log2 fold change in tumor volume of 1.1 for intravenous (IV) gemcitabine, 3.0 for IV saline, and 2.6 for device saline groups. The weekly coadministration of systemic cisplatin therapy and transdermal device cisplatin therapy significantly increased tumor growth inhibition and doubled the survival in two aggressive orthotopic models of breast cancer. The addition of radiotherapy to this treatment further extended survival. Device delivery of gemcitabine in dogs resulted in more than 7-fold difference in local drug concentrations and 25-fold lower systemic drug levels than the IV treatment. Overall, these devices have potential paradigm shifting implications for the treatment of pancreatic, breast, and other solid tumors. Copyright © 2015, American Association for the Advancement of Science.Science translational medicine 02/2015; 7(273):273ra14. DOI:10.1126/scitranslmed.3009951 · 14.41 Impact Factor
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ABSTRACT: Inflammatory breast cancer (IBC) is an aggressive type of breast cancer, characterized by very rapid progression, enlargement of the breast, skin edema causing an orange peel appearance (peau d'orange), erythema, thickening, and dermal lymphatic invasion. It is characterized by E-cadherin overexpression in the primary and metastatic disease, but to date no robust molecular features that specifically identify IBC have been reported. Further, models that recapitulate all of these clinical findings are limited and as a result no studies have demonstrated modulation of these clinical features as opposed to simply tumor cell growth. Hypothesizing the clinical presentation of IBC may be mediated in part by the microenvironment, we examined the effect of co-injection of IBC xenografts with mesenchymal stem/stromal cells (MSCs). MSCs co-injection significantly increased the clinical features of skin invasion and metastasis in the SUM149 xenograft model. Primary tumors co-injected with MSCs expressed higher phospho-epidermal growth factor receptor (p-EGFR) and promoted metastasis development after tumor resection, effects that were abrogated by treatment with the epidermal growth factor receptor (EGFR) inhibitor, erlotinib. E-cadherin expression was maintained in primary tumor xenografts with MSCs co-injection compared to control and erlotinib treatment dramatically decreased this expression in control and MSCs co-injected tumors. Tumor samples from patients demonstrate correlation between stromal and tumor p-EGFR staining only in IBC tumors. Our findings demonstrate that the IBC clinical phenotype is promoted by signaling from the microenvironment perhaps in addition to tumor cell drivers.Breast cancer research: BCR 12/2015; 17(1):42. DOI:10.1186/s13058-015-0549-4 · 5.88 Impact Factor
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ABSTRACT: Inflammatory breast cancer (IBC) is the most aggressive entity of breast cancer. Management involves coordination of multidisciplinary management and usually includes neoadjuvant chemotherapy, ablative surgery if a tumor-free resection margin is expected and locoregional radiotherapy. This multimodal therapeutic approach has significantly improved patient survival. However, the median overall survival among women with IBC is still poor. By elucidating the biologic characteristics of IBC, new treatment options may become available. We performed a comprehensive review of the English-language literature on IBC through computerized literature searches. The objective of the current review is to present an overview of the literature related to the biology, imaging and multidisciplinary treatment of inflammatory breast cancer.Critical Reviews in Oncology/Hematology 10/2014; 93(2). DOI:10.1016/j.critrevonc.2014.09.003 · 4.05 Impact Factor