RESUMO
Glioblastoma (GBM) is a highly lethal type of cancer. GBM recurrence following chemoradiation is typically attributed to the regrowth of invasive and resistant cells. Therefore, there is a pressing need to gain a deeper understanding of the mechanisms underlying GBM resistance to chemoradiation and its ability to infiltrate. Using a combination of transcriptomic, proteomic, and phosphoproteomic analyses, longitudinal imaging, organotypic cultures, functional assays, animal studies, and clinical data analyses, we demonstrate that chemoradiation and brain vasculature induce cell transition to a functional state named VC-Resist (vessel co-opting and resistant cell state). This cell state is midway along the transcriptomic axis between proneural and mesenchymal GBM cells and is closer to the AC/MES1-like state. VC-Resist GBM cells are highly vessel co-opting, allowing significant infiltration into the surrounding brain tissue and homing to the perivascular niche, which in turn induces even more VC-Resist transition. The molecular and functional characteristics of this FGFR1-YAP1-dependent GBM cell state, including resistance to DNA damage, enrichment in the G2M phase, and induction of senescence/stemness pathways, contribute to its enhanced resistance to chemoradiation. These findings demonstrate how vessel co-option, perivascular niche, and GBM cell plasticity jointly drive resistance to therapy during GBM recurrence.
Assuntos
Neoplasias Encefálicas , Glioblastoma , Glioblastoma/metabolismo , Glioblastoma/patologia , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Humanos , Animais , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Linhagem Celular Tumoral , Camundongos , Quimiorradioterapia/métodos , Resistencia a Medicamentos Antineoplásicos , Regulação Neoplásica da Expressão Gênica , Tolerância a Radiação , Proteínas de Sinalização YAP/metabolismo , Encéfalo/metabolismo , Encéfalo/patologia , ProteômicaRESUMO
Glioblastoma is a highly aggressive and invasive tumor that affects the central nervous system (CNS). With a five-year survival rate of only 6.9% and a median survival time of eight months, it has the lowest survival rate among CNS tumors. Its treatment consists of surgical resection, subsequent fractionated radiotherapy and concomitant and adjuvant chemotherapy with temozolomide. Despite the implementation of clinical interventions, recurrence is a common occurrence, with over 80% of cases arising at the edge of the resection cavity a few months after treatment. The high recurrence rate and location of glioblastoma indicate the need for a better understanding of the peritumor brain zone (PBZ). In this review, we first describe the main radiological, cellular, molecular and biomechanical tissue features of PBZ; and subsequently, we discuss its current clinical management, potential local therapeutic approaches and future prospects.
Assuntos
Neoplasias Encefálicas , Neoplasias do Sistema Nervoso Central , Glioblastoma , Humanos , Glioblastoma/patologia , Neoplasias Encefálicas/patologia , Encéfalo/patologia , Temozolomida/uso terapêutico , Neoplasias do Sistema Nervoso Central/patologiaRESUMO
Glioblastoma (GBM) is the most deadly type of malignant brain tumor, despite extensive molecular analyses of GBM cells. In recent years, the tumor microenvironment (TME) has been recognized as an important player and therapeutic target in GBM. However, there is a need for a full and integrated understanding of the different cellular and molecular components involved in the GBM TME and their interactions for the development of more efficient therapies. In this review, we provide a comprehensive report of the GBM TME, which assembles the contributions of physicians and translational researchers working on brain tumor pathology and therapy in France. We propose a holistic view of the subject by delineating the specific features of the GBM TME at the cellular, molecular, and therapeutic levels.
Assuntos
Neoplasias Encefálicas , Glioblastoma , Humanos , Glioblastoma/terapia , Glioblastoma/tratamento farmacológico , Microambiente Tumoral/genética , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/terapia , Neoplasias Encefálicas/patologiaRESUMO
Lactate is a central metabolite in brain physiology but also contributes to tumor development. Glioblastoma (GB) is the most common and malignant primary brain tumor in adults, recognized by angiogenic and invasive growth, in addition to its altered metabolism. We show herein that lactate fuels GB anaplerosis by replenishing the tricarboxylic acid (TCA) cycle in absence of glucose. Lactate dehydrogenases (LDHA and LDHB), which we found spatially expressed in GB tissues, catalyze the interconversion of pyruvate and lactate. However, ablation of both LDH isoforms, but not only one, led to a reduction in tumor growth and an increase in mouse survival. Comparative transcriptomics and metabolomics revealed metabolic rewiring involving high oxidative phosphorylation (OXPHOS) in the LDHA/B KO group which sensitized tumors to cranial irradiation, thus improving mouse survival. When mice were treated with the antiepileptic drug stiripentol, which targets LDH activity, tumor growth decreased. Our findings unveil the complex metabolic network in which both LDHA and LDHB are integrated and show that the combined inhibition of LDHA and LDHB strongly sensitizes GB to therapy.
Assuntos
Neoplasias Encefálicas , Glioblastoma , Lactato Desidrogenases , Animais , Camundongos , Ácido Láctico , Metabolômica , Glioblastoma/enzimologia , Glioblastoma/patologia , Neoplasias Encefálicas/enzimologia , Neoplasias Encefálicas/patologiaRESUMO
Therapeutic resistance after multimodal therapy is the most relevant cause of glioblastoma (GBM) recurrence. Extensive cellular heterogeneity, mainly driven by the presence of GBM stem-like cells (GSCs), strongly correlates with patients' prognosis and limited response to therapies. Defining the mechanisms that drive stemness and control responsiveness to therapy in a GSC-specific manner is therefore essential. Here we investigated the role of integrin a6 (ITGA6) in controlling stemness and resistance to radiotherapy in proneural and mesenchymal GSCs subtypes. Using cell sorting, gene silencing, RNA-Seq, and in vitro assays, we verified that ITGA6 expression seems crucial for proliferation and stemness of proneural GSCs, while it appears not to be relevant in mesenchymal GSCs under basal conditions. However, when challenged with a fractionated protocol of radiation therapy, comparable to that used in the clinical setting, mesenchymal GSCs were dependent on integrin a6 for survival. Specifically, GSCs with reduced levels of ITGA6 displayed a clear reduction of DNA damage response and perturbation of cell cycle pathways. These data indicate that ITGA6 inhibition is able to overcome the radioresistance of mesenchymal GSCs, while it reduces proliferation and stemness in proneural GSCs. Therefore, integrin a6 controls crucial characteristics across GBM subtypes in GBM heterogeneous biology and thus may represent a promising target to improve patient outcomes.
RESUMO
We recently developed an in vivo compression device that simulates the solid mechanical forces exerted by a growing tumor on the surrounding brain tissue and delineates the physical versus biological effects of a tumor. This device, to our knowledge the first of its kind, can recapitulate the compressive forces on the cerebellar cortex from primary (e.g., glioblastoma) and metastatic (e.g., breast cancer) tumors, as well as on the cerebellum from tumors such as medulloblastoma and ependymoma. We adapted standard transparent cranial windows normally used for intravital imaging studies in mice to include a turnable screw for controlled compression (acute or chronic) and decompression of the cerebral cortex. The device enables longitudinal imaging of the compressed brain tissue over several weeks or months as the screw is progressively extended against the brain tissue to recapitulate tumor growth-induced solid stress. The cranial window can be simply installed on the mouse skull according to previously established methods, and the screw mechanism can be readily manufactured in-house. The total time for construction and implantation of the in vivo compressive cranial window is <1 h (per mouse). This technique can also be used to study a variety of other diseases or disorders that present with abnormal solid masses in the brain, including cysts and benign growths.
Assuntos
Encéfalo/diagnóstico por imagem , Neuroimagem , Estresse Mecânico , Animais , Neoplasias Encefálicas/diagnóstico por imagem , Força Compressiva , Feminino , Masculino , CamundongosRESUMO
Vessel co-option is the movement of cancer cells towards and along the pre-existing vasculature and is an alternative to angiogenesis to gain access to nutrients. Vessel co-option has been shown as a strategy employed by some glioblastoma (GBM) cells to invade further into the brain, leading to one of the greatest challenges in treating GBM. In GBM, vessel co-option may be an intrinsic feature or an acquired mechanism of resistance to anti-angiogenic treatment. Here, we describe the histological features and the dynamics visualized through intravital microscopy of vessel co-option in GBM, as well as the molecular players discovered until now. We also highlight key unanswered questions, as answering these is critical to improve understanding of GBM progression and for developing more effective approaches for GBM treatment.
Assuntos
Neoplasias Encefálicas/irrigação sanguínea , Neoplasias Encefálicas/patologia , Glioblastoma/irrigação sanguínea , Glioblastoma/patologia , Neovascularização Patológica/patologia , Animais , Neoplasias Encefálicas/diagnóstico por imagem , Glioblastoma/diagnóstico por imagem , Humanos , Modelos Biológicos , Neovascularização Patológica/diagnóstico por imagem , Transdução de SinaisRESUMO
The compression of brain tissue by a tumour mass is believed to be a major cause of the clinical symptoms seen in patients with brain cancer. However, the biological consequences of these physical stresses on brain tissue are unknown. Here, via imaging studies in patients and by using mouse models of human brain tumours, we show that a subgroup of primary and metastatic brain tumours, classified as nodular on the basis of their growth pattern, exert solid stress on the surrounding brain tissue, causing a decrease in local vascular perfusion as well as neuronal death and impaired function. We demonstrate a causal link between solid stress and neurological dysfunction by applying and removing cerebral compression, which respectively mimic the mechanics of tumour growth and of surgical resection. We also show that, in mice, treatment with lithium reduces solid-stress-induced neuronal death and improves motor coordination. Our findings indicate that brain-tumour-generated solid stress impairs neurological function in patients, and that lithium as a therapeutic intervention could counter these effects.
Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/fisiopatologia , Lítio/uso terapêutico , Estresse Fisiológico , Animais , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Encéfalo/fisiopatologia , Neoplasias Encefálicas/irrigação sanguínea , Neoplasias Encefálicas/diagnóstico por imagem , Linhagem Celular Tumoral , Humanos , Camundongos Nus , Neurônios/efeitos dos fármacos , Neurônios/patologia , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , PerfusãoRESUMO
Abnormal blood and lymphatic vessels create a hostile tumor microenvironment characterized by hypoxia, low pH, and elevated interstitial fluid pressure. These abnormalities fuel tumor progression, immunosuppression, and treatment resistance. In 2001, we proposed a novel hypothesis that the judicious use of antiangiogenesis agents-originally developed to starve tumors-could transiently normalize tumor vessels and improve the outcome of anticancer drugs administered during the window of normalization. In addition to providing preclinical and clinical evidence in support of this hypothesis, we also revealed the underlying molecular mechanisms. In parallel, we demonstrated that desmoplasia could also impair vascular function by compressing vessels, and that normalizing the extracellular matrix could improve vascular function and treatment outcome in both preclinical and clinical settings. Here, we summarize the progress made in understanding and applying the normalization concept to cancer and outline opportunities and challenges ahead to improve patient outcomes using various normalizing strategies.
Assuntos
Hipóxia , Neoplasias/fisiopatologia , Neovascularização Patológica , Microambiente Tumoral , Animais , Humanos , Neoplasias/terapiaRESUMO
Solid stress, distinct from both tissue stiffness and fluid pressure, is a mechanical stress that is often elevated in both murine and human tumors. The importance of solid stress in tumor biology has been recognized in initial studies: solid stress promotes tumor progression and lowers the efficacy of anticancer therapies by compressing blood vessels and contributing to hypoxia. However, robust, reproducible, and objective methods that go beyond demonstration and bulk measurements have not yet been established. We have developed three new techniques to rigorously measure and map solid stress in both human and murine tumors that are able to account for heterogeneity in the tumor microenvironment. We describe here these methods and their independent advantages: 2D spatial mapping of solid stress (planar-cut method), sensitive estimation of solid stress in small tumors (slicing method), and in situ solid-stress quantification (needle-biopsy method). Furthermore, the preservation of tissue morphology and structure allows for subsequent histological analyses in matched tumor sections, facilitating quantitative correlations between solid stress and markers of interest. The three procedures each require â¼2 h of experimental time per tumor. The required skill sets include basic experience in tumor resection and/or biopsy (in mice or humans), as well as in intravital imaging (e.g., ultrasonography).
Assuntos
Elasticidade , Neoplasias/patologia , Patologia/métodos , Estresse Mecânico , Animais , Modelos Animais de Doenças , Humanos , CamundongosRESUMO
Gliomas comprise heterogeneous malignant glial and stromal cells. While blood vessel co-option is a potential mechanism to escape anti-angiogenic therapy, the relevance of glial phenotype in this process is unclear. We show that Olig2+ oligodendrocyte precursor-like glioma cells invade by single-cell vessel co-option and preserve the blood-brain barrier (BBB). Conversely, Olig2-negative glioma cells form dense perivascular collections and promote angiogenesis and BBB breakdown, leading to innate immune cell activation. Experimentally, Olig2 promotes Wnt7b expression, a finding that correlates in human glioma profiling. Targeted Wnt7a/7b deletion or pharmacologic Wnt inhibition blocks Olig2+ glioma single-cell vessel co-option and enhances responses to temozolomide. Finally, Olig2 and Wnt7 become upregulated after anti-VEGF treatment in preclinical models and patients. Thus, glial-encoded pathways regulate distinct glioma-vascular microenvironmental interactions.
Assuntos
Neoplasias Encefálicas/irrigação sanguínea , Glioma/irrigação sanguínea , Fator de Transcrição 2 de Oligodendrócitos/metabolismo , Oligodendroglia/microbiologia , Proteínas Wnt/metabolismo , Animais , Bevacizumab/farmacologia , Barreira Hematoencefálica/metabolismo , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioma/tratamento farmacológico , Glioma/metabolismo , Humanos , Camundongos , Transplante de Neoplasias , Fator de Transcrição 2 de Oligodendrócitos/genética , Temozolomida/farmacologia , Células Tumorais Cultivadas , Microambiente Tumoral , Proteínas Wnt/genética , Via de Sinalização Wnt/efeitos dos fármacosRESUMO
Lymph node metastases in cancer patients are associated with tumor aggressiveness, poorer prognoses, and the recommendation for systemic therapy. Whether cancer cells in lymph nodes can seed distant metastases has been a subject of considerable debate. We studied mice implanted with cancer cells (mammary carcinoma, squamous cell carcinoma, or melanoma) expressing the photoconvertible protein Dendra2. This technology allowed us to selectively photoconvert metastatic cells in the lymph node and trace their fate. We found that a fraction of these cells invaded lymph node blood vessels, entered the blood circulation, and colonized the lung. Thus, in mouse models, lymph node metastases can be a source of cancer cells for distant metastases. Whether this mode of dissemination occurs in cancer patients remains to be determined.
Assuntos
Vasos Sanguíneos/patologia , Linfonodos/patologia , Metástase Linfática/patologia , Inoculação de Neoplasia , Animais , Carcinoma de Células Escamosas , Linhagem Celular Tumoral , Movimento Celular , Rastreamento de Células/métodos , Citosol/química , Feminino , Proteínas Luminescentes/análise , Pulmão/patologia , Melanoma Experimental , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Células Neoplásicas CirculantesRESUMO
PURPOSE OF REVIEW: Brain tumors are composed of primary tumors of the central nervous system, such us glioblastoma (GBM), and secondary metastatic tumors, such as melanoma, non-Hodgkin lymphoma as well as lung and breast cancers. Brain tumors are highly deadly, and unfortunately not many improvements have been achieved to improve the survival of patients with brain tumors. Chemoradiation resistance is one of the most clinically relevant challenges faced in patients with brain tumors. The perivascular niche is one of the most relevant microenvironment hubs in brain tumors. The understanding of the cellular crosstalk established within the brain tumor perivascular niche might provide us with key discoveries of new brain tumor vulnerabilities. RECENT FINDINGS: Radio and chemoresistance in GBM and brain metastases is attributed to cancer stem cells (CSCs), which intrinsically modulate several pathways that make them resistant to therapy. Growing evidence, however, highlights the perivascular space as a niche for CSC survival, resistance to therapy, progression and dissemination. Here, I review the latest discoveries on the components and features of brain tumor vascular niches and the possible therapeutic strategies aimed at targeting its vulnerabilities, thus preventing GBM and metastasis chemoradiation resistance and recurrence. SUMMARY: Recent discoveries suggest that targeting the brain perivascular niche has the potential of sensitizing brain tumors to therapies and reducing the occurrence of metastases.
Assuntos
Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/terapia , Glioblastoma/patologia , Glioblastoma/terapia , Animais , Humanos , Microambiente TumoralRESUMO
Our understanding of cancer progression or response to therapies would benefit from benchtop, tissue-level assays that preserve the biology and anatomy of human tumours ex vivo. We present a methodology for maintaining patient tumour samples ex vivo for the purpose of drug testing in a clinical setting. The harvested tumour biopsy, excised from mice or patients, is integrated into a support tissue that includes stroma and vasculature. This support tissue preserves tumour histoarchitecture and relevant expression profiles, and tumour tissues cultured using this system display different sensitivities to chemotherapeutics compared with tumour explants with no supporting tissue. The methodology is more rapid than patient-derived xenograft models, easy to implement, and amenable to high-throughput assays, making it an attractive tool for in vitro drug screening or for the guidance of patient-specific chemotherapies.
Assuntos
Neoplasias Pancreáticas/irrigação sanguínea , Animais , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Camundongos , Neovascularização Patológica , Neoplasias Pancreáticas/patologiaRESUMO
The cerebellum is a prominent part of the vertebrate hindbrain that is critically involved in the regulation of important body functions such as movement coordination, maintenance of balance and posture, and motor control. Here, we describe a cerebellar window that provides access to the mouse cerebellum for intravital imaging, thereby allowing for a detailed characterization of the dynamic processes in this region of the brain. First, the skull overlying the cerebellum is removed, and then the window is applied to the region of interest. Windows may be exchanged depending on the desired imaging modality. This technique has a variety of applications. In the setting of medulloblastoma, spontaneous or orthotopically implanted lesions can be imaged, and tumor morphology and size can be monitored using ultrasonography. Multiphoton laser-scanning microscopy (MPLSM) or optical-frequency-domain imaging (OFDI) can be applied for in vivo visualization and analysis of cellular and vascular structures in a variety of disease states, including malignancies and ataxia telangiectasia. This protocol describes a novel and rapid method for cerebellar window construction that can be set up in under an hour.
Assuntos
Doenças Cerebelares/diagnóstico por imagem , Cerebelo/diagnóstico por imagem , Cerebelo/cirurgia , Microscopia Intravital/métodos , Animais , Modelos Animais de Doenças , Camundongos , Camundongos Nus , Camundongos SCID , Microscopia de Fluorescência por Excitação MultifotônicaRESUMO
In this chapter we describe a model of human angiogenesis where artery explants from umbilical cords are embedded in gel matrices and subsequently produce capillary-like structures. The human arterial ring (hAR) assay is an innovative system that enables three-dimensional (3D) and live studies of human angiogenesis. This ex vivo model has the advantage of recapitulating several steps of angiogenesis, including endothelial sprouting, migration, and differentiation into capillaries. Furthermore, it can be exploited for (1) identification of new genes regulating sprouting angiogenesis, (2) screening for pro- or anti-angiogenic drugs, (3) identification of biomarkers to monitor the efficacy of anti-angiogenic regimens, and (4) dynamic analysis of tumor microenvironmental effects on vessel formation.
Assuntos
Células Endoteliais/citologia , Neoplasias/irrigação sanguínea , Neovascularização Fisiológica , Cordão Umbilical/citologia , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Artérias , Diferenciação Celular , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Células Cultivadas , Técnicas de Cocultura , Células Endoteliais/metabolismo , Células HEK293 , Células HeLa , Humanos , Técnicas In Vitro , Neoplasias/metabolismo , Neovascularização Patológica/metabolismo , Microambiente Tumoral , Cordão Umbilical/metabolismoRESUMO
Glioblastomas (GBMs) rapidly become refractory to anti-VEGF therapies. We previously demonstrated that ectopic overexpression of angiopoietin-2 (Ang-2) compromises the benefits of anti-VEGF receptor (VEGFR) treatment in murine GBM models and that circulating Ang-2 levels in GBM patients rebound after an initial decrease following cediranib (a pan-VEGFR tyrosine kinase inhibitor) administration. Here we tested whether dual inhibition of VEGFR/Ang-2 could improve survival in two orthotopic models of GBM, Gl261 and U87. Dual therapy using cediranib and MEDI3617 (an anti-Ang-2-neutralizing antibody) improved survival over each therapy alone by delaying Gl261 growth and increasing U87 necrosis, effectively reducing viable tumor burden. Consistent with their vascular-modulating function, the dual therapies enhanced morphological normalization of vessels. Dual therapy also led to changes in tumor-associated macrophages (TAMs). Inhibition of TAM recruitment using an anti-colony-stimulating factor-1 antibody compromised the survival benefit of dual therapy. Thus, dual inhibition of VEGFR/Ang-2 prolongs survival in preclinical GBM models by reducing tumor burden, improving normalization, and altering TAMs. This approach may represent a potential therapeutic strategy to overcome the limitations of anti-VEGFR monotherapy in GBM patients by integrating the complementary effects of anti-Ang2 treatment on vessels and immune cells.
Assuntos
Anticorpos Antineoplásicos/farmacologia , Glioblastoma , Macrófagos , Proteínas de Neoplasias , Neoplasias Experimentais , Neovascularização Patológica , Quinazolinas/farmacologia , Receptores de Fatores de Crescimento do Endotélio Vascular , Ribonuclease Pancreático , Animais , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Glioblastoma/tratamento farmacológico , Glioblastoma/metabolismo , Glioblastoma/patologia , Macrófagos/metabolismo , Macrófagos/patologia , Camundongos , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/metabolismo , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Receptores de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Receptores de Fatores de Crescimento do Endotélio Vascular/metabolismo , Ribonuclease Pancreático/antagonistas & inibidores , Ribonuclease Pancreático/metabolismoRESUMO
Inhibition of the vascular endothelial growth factor (VEGF) pathway has failed to improve overall survival of patients with glioblastoma (GBM). We previously showed that angiopoietin-2 (Ang-2) overexpression compromised the benefit from anti-VEGF therapy in a preclinical GBM model. Here we investigated whether dual Ang-2/VEGF inhibition could overcome resistance to anti-VEGF treatment. We treated mice bearing orthotopic syngeneic (Gl261) GBMs or human (MGG8) GBM xenografts with antibodies inhibiting VEGF (B20), or Ang-2/VEGF (CrossMab, A2V). We examined the effects of treatment on the tumor vasculature, immune cell populations, tumor growth, and survival in both the Gl261 and MGG8 tumor models. We found that in the Gl261 model, which displays a highly abnormal tumor vasculature, A2V decreased vessel density, delayed tumor growth, and prolonged survival compared with B20. In the MGG8 model, which displays a low degree of vessel abnormality, A2V induced no significant changes in the tumor vasculature but still prolonged survival. In both the Gl261 and MGG8 models A2V reprogrammed protumor M2 macrophages toward the antitumor M1 phenotype. Our findings indicate that A2V may prolong survival in mice with GBM by reprogramming the tumor immune microenvironment and delaying tumor growth.
Assuntos
Anticorpos Biespecíficos/farmacologia , Anticorpos Antineoplásicos/farmacologia , Antineoplásicos/farmacologia , Glioblastoma/tratamento farmacológico , Macrófagos/metabolismo , Proteínas de Neoplasias/antagonistas & inibidores , Neoplasias Experimentais/tratamento farmacológico , Ribonuclease Pancreático/antagonistas & inibidores , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Proteínas de Transporte Vesicular/antagonistas & inibidores , Animais , Linhagem Celular Tumoral , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Macrófagos/patologia , Camundongos , Proteínas de Neoplasias/metabolismo , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Ribonuclease Pancreático/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Proteínas de Transporte Vesicular/metabolismo , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
BACKGROUND: Central nervous system (CNS) metastases represent a major problem in the treatment of human epidermal growth factor receptor 2 (HER2)-positive breast cancer because of the disappointing efficacy of HER2-targeted therapies against brain lesions. The antibody-drug conjugate ado-trastuzumab emtansine (T-DM1) has shown efficacy in trastuzumab-resistant systemic breast cancer. Here, we tested the hypothesis that T-DM1 could overcome trastuzumab resistance in murine models of brain metastases. METHODS: We treated female nude mice bearing BT474 or MDA-MB-361 brain metastases (n = 9-11 per group) or cancer cells grown in organotypic brain slice cultures with trastuzumab or T-DM1 at equivalent or equipotent doses. Using intravital imaging, molecular techniques and histological analysis we determined tumor growth, mouse survival, cancer cell apoptosis and proliferation, tumor drug distribution, and HER2 signaling. Data were analyzed with one-way analysis of variance (ANOVA), Kaplan-Meier analysis, and Coefficient of Determination. All statistical tests were two-sided. RESULTS: T-DM1 delayed the growth of HER2-positive breast cancer brain metastases compared with trastuzumab. These findings were consistent between HER2-driven and PI3K-driven tumors. The activity of T-DM1 resulted in a survival benefit (median survival for BT474 tumors: 28 days for trastuzumab vs 112 days for T-DM1, hazard ratio = 6.2, 95% confidence interval = 6.1 to 85.84, P < .001). No difference in drug distribution or HER2-signaling was revealed between the two groups. However, T-DM1 led to a statistically significant increase in tumor cell apoptosis (one-way ANOVA for ApopTag, P < .001), which was associated with mitotic catastrophe. CONCLUSIONS: T-DM1 can overcome resistance to trastuzumab therapy in HER2-driven or PI3K-driven breast cancer brain lesions due to the cytotoxicity of the DM1 component. Clinical investigation of T-DM1 for patients with CNS metastases from HER2-positive breast cancer is warranted.