RESUMO
Purpose: It has been suggested that dysregulation of transcription factors expression or activity plays significant roles in breast cancer (BC) severity and poor prognosis. Therefore, our study aims to thoroughly evaluate the estrogen-related receptor isoforms (ESRRs) expression and copy number alteration (CNA) status and their association with clinicopathologic characteristics in BC. Methods: A METABRIC dataset consist of 2509 BC patients' samples was obtained from the cBioPortal public domain. The gene expression, putative CNA, and relevant tumor information of ESRRs were retrieved. ESRRs messenger RNA (mRNA) expression in BC cell lines was obtained from the Cancer Cell Line Encyclopedia (CCLE). Association and correlation analysis of ESRRs expression with BC clinicopathologic characteristics and molecular subtype were performed. Kaplan-Meier survival analysis was conducted to evaluate the prognostic value of ESRRs expression on patient survival. Results: ESRRα expression correlated negatively with patients' age and overall survival, whereas positively correlated with tumor size, the number of positive lymph nodes, and Nottingham prognostic index (NPI). Conversely, ESRRγ expression was positively correlated with patients' age and negatively correlated with NPI. ESRRα and ESRRγ expression were significantly associated with tumor grade, expression of hormone receptors, human epidermal growth factor receptor 2 (HER2), and molecular subtype, whereas ESRRß was only associated with tumor stage. A significant and distinct association of each of ESRRs CNA with various clinicopathologic and prognostic factors was also observed. Kaplan-Meier survival analysis demonstrated no significant difference for survival curves among BC patients with high or low expression of ESRRα, ß, or γ. On stratification, high ESRRα expression significantly reduced survival among premenopausal patients, patients with grade I/II, and early-stage disease. In BC cell lines, only ESRRα expression was significantly higher in HER2-positive cells. No significant association was observed between ESRRß expression and any of the clinicopathologic characteristics examined. Conclusions: In this clinical dataset, ESRRα and ESRRγ mRNA expression and CNA show a significant correlation and association with distinct clinicopathologic and prognostic parameters known to influence treatment outcomes; however, ESRRß failed to show a robust role in BC pathogenesis. ESRRα and ESRRγ can be employed as therapeutic targets in BC-targeted therapy. However, the role of ESRRß in BC pathogenesis remains unclear.
RESUMO
Targeted therapy is a hallmark of cancer treatment that has changed the landscape of cancer management and enabled a personalized treatment approach. Nevertheless, the development of cancer resistance is a major challenge that is currently threatening the effective utilization of targeted therapies. The hepatocyte growth factor receptor, MET, is a receptor tyrosine kinase known for its oncogenic activity and tumorigenic potential. MET is a well-known driver of cancer resistance. A growing body of evidence revealed a major role of MET in mediating acquired resistance to several classes of targeted therapies. Deregulations of MET commonly associated with the development of cancer resistance include gene amplification, overexpression, autocrine activation, and crosstalk with other signaling pathways. Small-molecule tyrosine kinase inhibitors of MET are currently approved for the treatment of different solid cancers. This review summarizes the current evidence regarding MET-mediated cancer resistance toward targeted therapies. The molecular mechanisms associated with resistance are described along with findings from preclinical and clinical studies on using MET inhibitors to restore the anticancer activity of targeted therapies for the treatment of solid tumors.
Assuntos
Terapia de Alvo Molecular , Neoplasias/tratamento farmacológico , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Animais , Resistencia a Medicamentos Antineoplásicos , Amplificação de Genes , Humanos , Mutação , Proteínas Proto-Oncogênicas c-met/genética , Proteínas Proto-Oncogênicas c-met/fisiologiaRESUMO
Hormone-dependent breast cancer is the most abundant molecular subtype of the disease. Despite the availability of endocrine treatments, the use of these drugs is limited by their serious adverse reactions and development of acquired resistance often mediated by growth factor receptors. The hepatocyte growth factor receptor, MET, is a receptor tyrosine kinase known for its oncogenic activity and mediating resistance to targeted therapies. Crizotinib is a small-molecule tyrosine kinase inhibitor of MET. In this study, the anticancer effects of combined crizotinib and endocrine drugs were investigated in breast cancer cells in vitro along with the molecular mechanisms associated with these effects. Results showed that crizotinib inhibited growth of MCF7 and T-47D breast cancer cells in a dose-dependent manner with IC50 values of 2.88 µM and 0.93 µM, respectively. Combined treatment of crizotinib and 4-hydroxytamoxifen resulted in synergistic growth inhibition of MCF7 and T-47D cells with combination index values of 0.39 and 0.8, respectively. The combined treatment significantly suppressed migration and colony formation of MCF7 and T-47D cells. Immunofluorescence showed a significant reduction of the expression of the nuclear protein Ki-67 with the combination of crizotinib and 4-hydroxytamoxifen in both cell lines. Western blotting indicated that the combination treatment reduced the levels of active and total MET, estrogen receptor α (ERα), total and active levels of AKT, ERK, c-SRC, NFĸB p65, GSK-3ß, and the anti-apoptotic BCL-2 protein. Findings from this study suggest a potential role of MET inhibitors in breast cancer treatment as monotherapy or combination with endocrine drugs.
Assuntos
Antineoplásicos Hormonais/farmacologia , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Crizotinibe/farmacologia , Receptor alfa de Estrogênio/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-met/metabolismo , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Sinergismo Farmacológico , Fulvestranto/farmacologia , Humanos , Concentração Inibidora 50 , Antígeno Ki-67/metabolismo , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Tamoxifeno/análogos & derivados , Tamoxifeno/farmacologiaRESUMO
MET is a receptor tyrosine kinase known to drive neoplastic transformation and aggressive tumor phenotypes. Crizotinib is an oral multi-targeted tyrosine kinase inhibitor of MET, ALK, RON, and ROS1 kinases. In this study, the anticancer effects of crizotinib on breast cancer cells were investigated in vitro along with the molecular mechanisms associated with these effects. Besides, the antiproliferative effects of crizotinib in combination with chemotherapy, hormonal drugs, and targeted agents were examined. Results showed that crizotinib produced dose-dependent antiproliferative effects in BT-474 and SK-BR-3 breast cancer cells with IC50 values of 1.7 µM and 5.2 µM, respectively. Crizotinib inhibited colony formation of BT-474 cells at low micromolar concentrations (1-5 µM). Immunofluorescence and Western blotting indicated that crizotinib reduced total levels of MET and estrogen receptor (ERα) in BT-474 cells. Also, crizotinib reduced the levels of phosphorylated (active) MET and HER2 in BT-474 cells. The combined treatment of crizotinib with doxorubicin and paclitaxel resulted in synergistic growth inhibition of BT-474 cells with combination index values of 0.46 and 0.35, respectively. Synergy was also observed with the combination of crizotinib with the hormonal drugs 4-hydroxytamoxifen and fulvestrant in BT-474 cells. Alternatively, the combination of crizotinib with lapatinib produced antagonistic antiproliferative effects in both BT-474 and SK-BR-3 cells. Collectively, these findings demonstrate the anticancer effects of crizotinib in breast cancer cells and reveal ERα as a potential therapeutic target of the drug apart from its classical kinase inhibitory activity. Crizotinib could be an appealing option in combination with chemotherapy or hormonal drugs for the management of breast cancer.