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Prophylactic cranial irradiation (PCI) can reduce the incidence of brain metastasis and improve overall survival in some patients with acute lymphoblastic leukemia or small-cell lung cancer. We examined the potential effects of PCI in a mouse model of breast cancer brain metastasis. The HER2+ inflammatory breast cancer cell line MDA-IBC3 was labeled with green fluorescent protein and injected via tail-vein into female SCID/Beige mice. Mice were then given 0 Gy or 4 Gy of whole-brain irradiation 2 days before tumor-cell injection or 5 days, 3 weeks, or 6 weeks after tumor-cell injection. Mice were sacrificed 4-weeks or 8-weeks after injection and brain tissues were examined for metastasis by fluorescent stereomicroscopy. In the unirradiated control group, brain metastases were present in 77% of mice at 4 weeks and in 90% of mice at 8 weeks; by comparison, rates for the group given PCI at 5 days after tumor-cell injection were 20% at 4 weeks (p=0.01) and 30% at 8 weeks (p=0.02). The PCI group also had fewer brain metastases per mouse at 4 weeks (p=0.03) and 8 weeks (p=0.006) versus the unirradiated control as well as a lower metastatic burden (p=0.01). Irradiation given either before tumor-cell injection or 3-6 weeks afterward had no significant effect on brain metastases compared to the unirradiated control. These results underscore the importance of timing for irradiating subclinical disease. Clinical whole brain strategies to target subclinical brain disease as safely as possible may warrant further study.
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Glioblastoma is an aggressive brain tumor with a propensity for intracranial recurrence. We hypothesized that tumors can be visualized with diffusion tensor imaging (DTI) before they are detected on anatomical magnetic resonance (MR) images. We retrospectively analyzed serial MR images from 30 patients, including the DTI and T1-weighted images at recurrence, at 2 months and 4 months before recurrence, and at 1 month after radiation therapy. The diffusion maps and T1 images were deformably registered longitudinally. The recurrent tumor was manually segmented on the T1-weighted image and then applied to the diffusion maps at each time point to collect mean FA, diffusivities, and neurite density index (NDI) values, respectively. Group analysis of variance showed significant changes in FA (p = 0.01) and NDI (p = 0.0015) over time. Pairwise t tests also revealed that FA and NDI at 2 months before recurrence were 11.2% and 6.4% lower than those at 1 month after radiation therapy (p < 0.05), respectively. Changes in FA and NDI were observed 2 months before recurrence, suggesting that progressive microstructural changes and neurite density loss may be detectable before tumor detection in anatomical MR images. FA and NDI may serve as non-contrast MR-based biomarkers for detecting subclinical tumors.
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INTRODUCTION: Although most NSCLC patients with sensitizing epidermal growth factor receptor (EGFR) mutations have an impressive initial response, the vast majority has residual disease and develops acquired resistance after 9 to 14 months of EGFR tyrosine kinase (TKI) therapy. We recently reported a phase II trial showing that, for patients with molecularly unselected oligometastatic NSCLC who did not progress after first-line systemic therapy, local consolidation therapy (LCT) with surgery or radiation improved progression-free survival (PFS), compared with maintenance therapy alone. Herein, we report a retrospective analysis of LCT after TKI in patients with metastatic EGFR mutant NSCLC. PATIENTS AND METHODS: We identified patients with metastatic EGFR mutant NSCLC treated with TKI plus LCT or with TKI alone in the MD Anderson GEMINI (Genomic Marker-Guided Therapy Initiative) database and in our recently published LCT trial. PFS was compared between LCT plus TKI and TKI only treated patients using the log-rank test. RESULTS: We identified 129 patients with EGFR mutant NSCLC who were treated with first-line TKI and 12 that were treated with TKI followed by LCT. Among the 12 patients treated with TKI plus LCT, 8 patients had oligometastatic disease (defined as ≤ 3 metastases), and 4 patients had > 3 metastases. LCT regimens were hypofractionated radiotherapy or stereotactic ablative body radiotherapy for 11 patients and surgery for 1 patient. TKI followed by LCT resulted in a significantly longer PFS (36 months) compared with TKI alone (PFS, 14 months; log-rank P = .0024). CONCLUSIONS: Our data suggests that first-line TKI plus LCT is a promising therapeutic strategy for patients with EGFR mutant NSCLC that merits further investigation.
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Carcinoma Pulmonar de Células não Pequenas/terapia , Quimioterapia de Consolidação , Neoplasias Pulmonares/terapia , Inibidores de Proteínas Quinases/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Receptores ErbB/genética , Feminino , Humanos , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Mutação/genética , Metástase Neoplásica , Análise de SobrevidaRESUMO
PURPOSE: Osimertinib was initially approved for T790M-positive non-small cell lung cancer (NSCLC) and, more recently, for first-line treatment of EGFR-mutant NSCLC. However, resistance mechanisms to osimertinib have been incompletely described. EXPERIMENTAL DESIGN: Using cohorts from The University of Texas MD Anderson Lung Cancer Moonshot GEMINI and Moffitt Cancer Center lung cancer databases, we collected clinical data for patients treated with osimertinib. Molecular profiling analysis was performed at the time of progression in a subset of the patients. RESULTS: In the 118 patients treated with osimertinib, 42 had molecular profiling at progression. T790M was preserved in 21 (50%) patients and lost in 21 (50%). EGFR C797 and L792 (26%) mutations were the most common resistance mechanism and were observed exclusively in T790M-preserved cases. MET amplification was the second most common alteration (14%). Recurrent alterations were observed in 22 genes/pathways, including PIK3CA, FGFR, and RET. Preclinical studies confirmed MET, PIK3CA, and epithelial-to-mesenchymal transition as potential resistance drivers. Alterations of cell-cycle genes were associated with shorter median progression-free survival (PFS, 4.4 vs. 8.8 months, P = 0.01). In 76 patients with progression, osimertinib was continued in 47 cases with a median second PFS (PFS2) of 12.6 months; 21 patients received local consolidation radiation with a median PFS of 15.5 months. Continuation of osimertinib beyond progression was associated with a longer overall survival compared with discontinuation (11.2 vs. 6.1 months, P = 0.02). CONCLUSIONS: Osimertinib resistance is associated with diverse, predominantly EGFR-independent genomic alterations. Continuation of osimertinib after progression, alone or in conjunction with radiotherapy, may provide prolonged clinical benefit in selected patients.See related commentary by Devarakonda and Govindan, p. 6112.
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Acrilamidas/uso terapêutico , Compostos de Anilina/uso terapêutico , Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Resistencia a Medicamentos Antineoplásicos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Mutação , Acrilamidas/administração & dosagem , Acrilamidas/efeitos adversos , Adulto , Idoso , Compostos de Anilina/administração & dosagem , Compostos de Anilina/efeitos adversos , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/patologia , Resistencia a Medicamentos Antineoplásicos/genética , Receptores ErbB/genética , Feminino , Humanos , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Terapia de Alvo Molecular , Prognóstico , Inibidores de Proteínas Quinases/administração & dosagem , Inibidores de Proteínas Quinases/efeitos adversos , Inibidores de Proteínas Quinases/uso terapêutico , Estudos Retrospectivos , Análise de Sobrevida , Resultado do TratamentoRESUMO
INTRODUCTION: Exploratory analysis of clinical trials in various tumor types have demonstrated potential improvements in overall response rate (ORR) to chemotherapy after exposure to vaccine-based immunotherapy. The objective of this retrospective study was to determine if single-agent chemotherapy (3rd-line or beyond) would yield improved ORR when given after exposure to programmed death-(ligand)1 inhibitors (anti-PD1) in metastatic non-small cell lung cancer (NSCLC). MATERIALS AND METHODS: We queried the Thoracic GEMINI database of MD Anderson Cancer Center for patients treated between 06/12 and 11/16 who received at least one single-agent chemotherapy as 3rd-line or beyond, following progression after platinum-based chemotherapy and anti-PD1. We evaluated efficacy outcomes to each therapy, including ORR by RECIST version 1.1, progression-free survival (PFS), and overall survival (OS). RESULTS: Out of 306 anti-PD1-treated patients registered in the database, 28 met eligibility criteria - 54% were male, median age was 66 years, 82% had adenocarcinoma, and 71% were former/current smokers. The anti-PD1 and single-agent chemotherapy most commonly used were nivolumab (86%) and docetaxel (50%), respectively. ORR to single-agent chemotherapy after exposure to anti-PD1 was 39% (11/28 patients, 8 confirmed). In contrast, ORR to first-line chemotherapy in this cohort was 37%. Liver metastasis was the only factor associated with response to single-agent chemotherapy on univariate analysis (p<0.05). CONCLUSION: In NSCLC patients, the confirmed ORR to single-agent chemotherapy after immunotherapy exposure was higher as compared to historical data from the pre-anti-PD1 era, and approached ORR to first-line platinum-based chemotherapy. Further investigation of a possible immunotherapy-induced chemosensitization effect is warranted.
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Antineoplásicos Imunológicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais , Carcinoma Pulmonar de Células não Pequenas/imunologia , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Feminino , Humanos , Imunomodulação/efeitos dos fármacos , Imunoterapia , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Terapia de Alvo Molecular , Mutação , Estadiamento de Neoplasias , Análise de Sobrevida , Resultado do TratamentoRESUMO
PURPOSE: We recently demonstrated that histone deacetylase (HDAC) inhibitors can "reprogram" differentiated triple-negative breast cancer cells to become quiescent stem-like cancer cells. We hypothesized that the metabolic state of such cells differs from that of their differentiated progeny. RESULTS: In untreated cells, glucose uptake was higher in ALDH+ cells than in ALDH- cells (p = 0.01) but lactate production was not different; treating ALDH- or ALDH+ cells with VA or SAHA similarly increased glucose uptake without changing lactate production but upregulated G6PD, a rate-limiting enzyme in pentose phosphate pathway metabolism. NADPH production was higher in HDAC inhibitor-treated stem-like cells than in vehicle-treated cells (p < 0.05). Two G6PD inhibitors, 6-aminonicotinamide and dehydroepiandrosterone, decreased mammosphere formation efficiency and ALDH activity and 6-aminonicotinamide reduced the VA-induced increase in ALDH+ cells. Finally, patients expressing high G6PD mRNA had significantly worse overall survival (p < 0.001), and patients with high G6PD protein showed a similar trend towards worse disease-specific survival (p = 0.06). METHODS: Glucose consumption, lactate and NADPH production, and reactive oxygen species generation were compared in aldehyde dehydrogenase (ALDH)-positive and -negative cells in the presence or absence of the HDAC inhibitors valproic acid (VA) or suberoylanilide hydroxamic acid (SAHA). Glucose-6-phosphate dehydrogenase (G6PD) expression was evaluated in a tissue microarray from 94 patients with node-positive invasive breast carcinoma and in two publically available databases and correlated with overall survival. CONCLUSIONS: Energy metabolism in HDAC inhibitor-induced stem-like cancer cells differed sharply from that of differentiated cell types. HDAC inhibitor-induced dedifferentiation promoted metabolic reprogramming into the pentose phosphate pathway, which is targeted effectively by G6PD inhibition. These findings highlight a potential dual-therapy approach to targeting bulk differentiated cells with HDAC inhibitors and CSCs with G6PD inhibitors.
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Desdiferenciação Celular/efeitos dos fármacos , Inibidores de Histona Desacetilases/farmacologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Neoplasias de Mama Triplo Negativas/metabolismo , Linhagem Celular Tumoral , Feminino , Glucosefosfato Desidrogenase/metabolismo , Humanos , Via de Pentose Fosfato/efeitos dos fármacos , Neoplasias de Mama Triplo Negativas/patologiaRESUMO
BACKGROUND: Brain metastasis poses a major treatment challenge and remains an unmet clinical need. Finding novel therapies to prevent and treat brain metastases requires an understanding of the biology and molecular basis of the process, which currently is constrained by a dearth of experimental models and specific therapeutic targets. METHODS: Green Fluorescent Protein (GFP)-labeled breast cancer cells were injected via tail vein into SCID/Beige mice (n = 10-15 per group), and metastatic colonization to the brain and lung was evaluated eight weeks later. Knockdown and overexpression of miR-141 were achieved with lentiviral vectors. Serum levels of miR-141 were measured from breast cancer patients (n = 105), and the association with clinical outcome was determined by Kaplan-Meier method. All statistical tests were two-sided. RESULTS: Novel brain metastasis mouse models were developed via tail vein injection of parental triple-negative and human epidermal growth factor receptor 2 (HER2)-overexpressing inflammatory breast cancer lines. Knockdown of miR-141 inhibited metastatic colonization to brain (miR-141 knockdown vs control: SUM149, 0/8 mice vs 6/9 mice,P= .009; MDA-IBC3, 2/14 mice vs 10/15 mice,P= .007). Ectopic expression of miR-141 in nonexpressing MDA-MB-231 enhanced brain metastatic colonization (5/9 mice vs 0/10 mice,P= .02). Furthermore, high miR-141 serum levels were associated with shorter brain metastasis-free survival (P= .04) and were an independent predictor of progression-free survival (hazard ratio [HR] = 4.77, 95% confidence interval [CI] = 2.61 to 8.71,P< .001) and overall survival (HR = 7.22, 95% CI = 3.46 to 15.06,P< .001). CONCLUSIONS: Our study suggests miR-141 is a regulator of brain metastasis from breast cancer and should be examined as a biomarker and potential target to prevent and treat brain metastases.
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Neoplasias Encefálicas/genética , Neoplasias Encefálicas/secundário , Carcinoma Ductal de Mama/genética , MicroRNAs/genética , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia , Animais , Neoplasias Encefálicas/sangue , Caderinas/metabolismo , Carcinoma Ductal de Mama/sangue , Carcinoma Ductal de Mama/secundário , Linhagem Celular Tumoral , Modelos Animais de Doenças , Intervalo Livre de Doença , Feminino , Técnicas de Silenciamento de Genes , Humanos , Camundongos , MicroRNAs/sangue , Valor Preditivo dos Testes , Receptor ErbB-2/metabolismo , Taxa de Sobrevida , Neoplasias de Mama Triplo Negativas/sangueRESUMO
We previously reported using statins was correlated with improved metastasis-free survival in aggressive breast cancer. The purpose of this study was to examine the effect of statins on metastatic colonization by triple-negative breast cancer (TNBC) cells. TNBC cell lines were treated with simvastatin and then studied for cell cycle progression and proliferation in vitro, and metastasis formation in vivo, following injection of statin-treated cells. Reverse-phase protein assay (RPPA) analysis was performed on statin-treated and control breast cancer cells. RNA interference targeting FOXO3a was used to measure the impact of simvastatin on FOXO3a-expressing cells. The prognostic value of FOXO3a mRNA expression was examined in eight public breast cancer gene expression datasets including 1479 patients. Simvastatin increased G1/S-phase arrest of the cell cycle and inhibited both proliferation and migration of TNBC cells in vitro. In vitro pre-treatment and in vivo treatment with simvastatin reduced metastases. Phosphorylated FOXO3a was downregulated after simvastatin treatment in (RPPA) analysis. Ectopic expression of FOXO3a enhanced mammosphere formation and migratory capacity in vitro. Knockdown of FOXO3a attenuated the effect of simvastatin on mammosphere formation and migration. Analysis of public gene expression data demonstrates FOXO3a mRNA downregulation was independently associated with shorter metastasis-free survival in all breast cancers, as well as in TNBC breast cancers. Simvastatin inhibits in vitro endpoints associated with metastasis through a FOXO3a mechanism and reduced metastasis formation in vivo. FOXO3a expression is prognostic for metastasis formation in patient data. Further investigation of simvastatin as a cancer therapy is warranted.
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Antineoplásicos/farmacologia , Fatores de Transcrição Forkhead/metabolismo , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Sinvastatina/farmacologia , Neoplasias de Mama Triplo Negativas/patologia , Animais , Linhagem Celular Tumoral/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Feminino , Proteína Forkhead Box O3 , Fatores de Transcrição Forkhead/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos SCID , Pessoa de Meia-Idade , Metástase Neoplásica , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
INTRODUCTION: 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. METHODS: 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). RESULTS: 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. CONCLUSIONS: Our findings demonstrate that the IBC clinical phenotype is promoted by signaling from the microenvironment perhaps in addition to tumor cell drivers.
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Neoplasias Inflamatórias Mamárias/metabolismo , Neoplasias Inflamatórias Mamárias/patologia , Células-Tronco Mesenquimais/metabolismo , Fenótipo , Animais , Antineoplásicos/farmacologia , Caderinas/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Meios de Cultivo Condicionados/metabolismo , Meios de Cultivo Condicionados/farmacologia , Modelos Animais de Doenças , Receptores ErbB/metabolismo , Cloridrato de Erlotinib/farmacologia , Feminino , Xenoenxertos , Humanos , Neoplasias Inflamatórias Mamárias/genética , Neoplasias Inflamatórias Mamárias/mortalidade , Camundongos , Invasividade Neoplásica , Metástase Neoplásica , Transdução de Sinais/efeitos dos fármacos , Células Estromais/metabolismo , Carga Tumoral/efeitos dos fármacosRESUMO
Reported rates of local failure after adjuvant radiation for women with inflammatory breast cancer (IBC) and triple-negative non-IBC are higher than those of women with receptor-expressing non-IBC. These high rates of locoregional recurrence are potentially influenced by the contribution of radioresistant cancer stem cells to these cancers. Statins have been shown to target stem cells and improve disease-free survival among IBC patients. We examined simvastatin radiosensitization of multiple subtypes of breast cancer cell lines in vitro in monolayer and mammosphere-based clonogenic assays and examined the therapeutic benefit of statin use on local control after postmastectomy radiation (PMRT) among IBC patients. We found that simvastatin radiosensitizes mammosphere-initiating cells (MICs) of IBC cell lines (MDA-IBC3, SUM149, SUM190) and of the metaplastic, non-IBC triple-negative receptor cell line (SUM159). However, simvastatin radioprotects MICs of non-IBC cell lines MCF-7 and SKBR3. In a retrospective clinical study of 519 IBC patients treated with PMRT, 53 patients used a statin. On univariate analysis, actuarial 3-year local recurrence-free survival (LRFS) was higher among statin users, and on multivariate analysis, triple negative breast cancer, absence of lymphatic invasion, neoadjuvant pathological tumor response to preoperative chemotherapy, and statin use were independently associated with higher LRFS. In conclusion, patients with IBC and triple-negative non-IBC breast cancer have the highest rates of local failure, and there are no available known radiosensitizers. We report significant improvement in local control after PMRT among statin users with IBC and significant radiosensitization across triple-negative and IBC cell lines of multiple subtypes using simvastatin. These data suggest that simvastatin should be justified as a radiosensitizing agent by a prospective clinical trial.
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Diferenciação Celular , Neoplasias Inflamatórias Mamárias/terapia , Mastectomia , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/efeitos da radiação , Tolerância a Radiação , Radiossensibilizantes/uso terapêutico , Sinvastatina/uso terapêutico , Neoplasias de Mama Triplo Negativas/terapia , Adulto , Idoso , Distribuição de Qui-Quadrado , Progressão da Doença , Intervalo Livre de Doença , Feminino , Humanos , Neoplasias Inflamatórias Mamárias/imunologia , Neoplasias Inflamatórias Mamárias/mortalidade , Neoplasias Inflamatórias Mamárias/patologia , Estimativa de Kaplan-Meier , Células MCF-7 , Pessoa de Meia-Idade , Análise Multivariada , Recidiva Local de Neoplasia , Células-Tronco Neoplásicas/imunologia , Células-Tronco Neoplásicas/patologia , Modelos de Riscos Proporcionais , Radioterapia Adjuvante , Estudos Retrospectivos , Fatores de Risco , Esferoides Celulares , Fatores de Tempo , Resultado do Tratamento , Neoplasias de Mama Triplo Negativas/imunologia , Neoplasias de Mama Triplo Negativas/mortalidade , Neoplasias de Mama Triplo Negativas/patologia , Adulto JovemRESUMO
WNT signaling plays a key role in the self-renewal of tumor initiation cells (TICs). In this study, we used pyrvinium pamoate (PP), an FDA-approved antihelmintic drug that inhibits WNT signaling, to test whether pharmacologic inhibition of WNT signaling can specifically target TICs of aggressive breast cancer cells. SUM-149, an inflammatory breast cancer cell line, and SUM-159, a metaplastic basal-type breast cancer cell line, were used in these studies. We found that PP inhibited primary and secondary mammosphere formation of cancer cells at nanomolar concentrations, at least 10 times less than the dose needed to have a toxic effect on cancer cells. A comparable mammosphere formation IC50 dose to that observed in cancer cell lines was obtained using malignant pleural effusion samples from patients with IBC. A decrease in activity of the TIC surrogate aldehyde dehydrogenase was observed in PP-treated cells, and inhibition of WNT signaling by PP was associated with down-regulation of a panel of markers associated with epithelial-mesenchymal transition. In vivo, intratumoral injection was associated with tumor necrosis, and intraperitoneal injection into mice with tumor xenografts caused significant tumor growth delay and a trend toward decreased lung metastasis. In in vitro mammosphere-based and monolayer-based clonogenic assays, we found that PP radiosensitized cells in monolayer culture but not mammosphere culture. These findings suggest WNT signaling inhibition may be a feasible strategy for targeting aggressive breast cancer. Investigation and modification of the bioavailability and toxicity profile of systemic PP are warranted.
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Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Compostos de Pirvínio/farmacologia , Radiossensibilizantes/farmacologia , Animais , Anti-Helmínticos/farmacologia , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Transição Epitelial-Mesenquimal , Feminino , Humanos , Concentração Inibidora 50 , Neoplasias Pulmonares/secundário , Camundongos , Camundongos Nus , Camundongos SCID , Células-Tronco Neoplásicas/efeitos dos fármacos , Tolerância a Radiação/efeitos dos fármacos , Esferoides Celulares/efeitos dos fármacos , Esferoides Celulares/fisiologia , Via de Sinalização Wnt , Ensaios Antitumorais Modelo de Xenoenxerto , beta Catenina/metabolismoRESUMO
Study of the mechanisms understanding how chemically functionalized carbon nanotubes internalize into mammalian cells is important in view of their design as new tools for therapeutic and diagnostic applications. The initial contact between the nanotube and the cell membrane allows elucidation of the types of interaction that are occurring and the contribution from the types of functional groups at the nanotube surface. Here we offer a combination of experimental and theoretical evidence of the initial phases of interaction between functionalized carbon nanotubes with model and cellular membranes. Both experimental and theoretical data reveal the critical parameters to determine direct translocation of the nanotubes through the membrane into the cytoplasm as a result of three distinct processes that can be summarized as landing, piercing and uptake.
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Membrana Celular/química , Nanotubos de Carbono/química , Animais , Linhagem Celular Tumoral , Membrana Celular/metabolismo , Citoplasma/química , Citoplasma/metabolismo , Humanos , Lipossomos/química , Microscopia Eletrônica de Transmissão , Simulação de Dinâmica Molecular , TemperaturaRESUMO
Recent studies have shown that differentiated cancer cells can dedifferentiate into cancer stem cells (CSCs) although to date no studies have reported whether this transition is influenced by systemic anti-cancer agents. Valproic acid (VA) is a histone deacetylase (HDAC) inhibitor that promotes self-renewal and expansion of hematopoietic stem cells and facilitates the generation of induced pluripotent stem cells from somatic cells and is currently being investigated in breast cancer clinical trials. We hypothesized that HDAC inhibitors reprogram differentiated cancer cells toward the more resistant stem cell-like state. Two highly aggressive breast cancer cell lines, SUM159 and MDA-231, were sorted based on aldehyde dehydrogenase (ALDH) activity and subsequently ALDH-negative and ALDH-positive cells were treated with one of two known HDAC inhibitors, VA or suberoylanilide hydroxamic acid. In addition, primary tumor cells from patients with metastatic breast cancer were evaluated for ALDH activity following treatment with HDAC inhibitors. We demonstrate that single-cell-sorted ALDH-negative cells spontaneously generated ALDH-positive cells in vitro. Treatment of ALDH-negative cells with HDAC inhibitors promoted the expansion of ALDH-positive cells and increased mammosphere-forming efficiency. Most importantly, it significantly increased the tumor-initiating capacity of ALDH-negative cells in limiting dilution outgrowth assays. Moreover, while HDAC inhibitors upregulated ß-catenin expression and significantly increased WNT reporter activity, a TCF4 dominant negative construct abolished HDAC-inhibitor-induced expansion of CSCs. These results demonstrate that HDAC inhibitors promote the expansion of breast CSCs through dedifferentiation and have important clinical implications for the use of HDAC inhibitors in the treatment of cancer.
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Desdiferenciação Celular/efeitos dos fármacos , Inibidores de Histona Desacetilases/farmacologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Ácido Valproico/farmacologia , Via de Sinalização Wnt/efeitos dos fármacos , Aldeído Desidrogenase/metabolismo , Animais , Antineoplásicos/farmacologia , Neoplasias da Mama , Proliferação de Células/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos , Transição Epitelial-Mesenquimal/genética , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos , Camundongos SCID , Transplante de Neoplasias , Células-Tronco Neoplásicas/fisiologia , Paclitaxel/farmacologia , Esferoides Celulares/efeitos dos fármacos , Células Tumorais CultivadasRESUMO
Understanding the mechanisms responsible for carbon nanotube (CNT) internalisation into live cells is considered critical both from a fundamental point of view and for further engineering of CNT-based delivery systems to intracellular targets. While several studies are focused on the development of such CNT-based delivery systems, attempts to systematically elucidate the cellular uptake mechanisms of CNTs are still rather limited. The aim of the present study is to evaluate the cellular internalisation of chemically functionalised multi-walled carbon nanotubes (f-MWCNTs) in the presence of different well-known cellular uptake inhibitors. Our data reveal how f-MWCNTs are able to translocate across cell membranes of both phagocytic and non-phagocytic cell lines. We have evidenced that at least 30-50% of f-MWCNTs are taken up by cells through an energy-independent mechanism. This characteristic makes nanotubes loaded with therapeutic or diagnostic cargos extremely interesting as the release of active molecules directly into the cytoplasm increase their biological activity and therapeutic efficacy.
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Membrana Celular/fisiologia , Macrófagos/fisiologia , Fagocitose/fisiologia , Animais , Linhagem Celular , Camundongos , Nanotubos de CarbonoRESUMO
Tetrandrine is a bisbenzylisoquinoline alkaloid found in Stephania tetrandra, a Chinese medicine commonly used as an anti-inflammatory. It has extensive pharmacological activity, including positive ion channel blockade and inhibition of multiple drug resistance proteins. These activities are very similar to that of salinomycin, a known drug targeting breast cancer initiation cells (TICs). Herein, we tested tetrandrine targeting of breast cancer TICs. SUM-149, an inflammatory breast cancer cell line and SUM-159, a non-inflammatory metaplastic breast cancer cell line were used in these studies. In proliferation assays using 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS), we found that the IC50 for inhibition of proliferation is 15.3 ± 4.1 µM for SUM-149 and 24.3 ± 2.1 µM for SUM-159 cells. Tetrandrine also inhibited mammosphere formation, a surrogate for breast cancer TICs growth in vitro with IC50 around 1 µM for SUM-149 and around 2 µM for SUM-159 cells. Tetrandrine has similar effects on the mammosphere formation from cells isolated from fresh patient sample. Moreover, tetrandrine decreases the aldehyde dehydrogenase (ALDH) positive population in SUM-159 by 45% ± 5.45% P = 0.005. In summary, tetrandrine demonstrates significant efficacy against in vitro surrogates for inflammatory and aggressive breast cancer TICs.
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INTRODUCTION: Normal and malignant breast tissue contains a rare population of multi-potent cells with the capacity to self-renew, referred to as stem cells, or tumor initiating cells (TIC). These cells can be enriched by growth as "mammospheres" in three-dimensional cultures. OBJECTIVE: We tested the hypothesis that human bone-marrow derived mesenchymal stem cells (MSC), which are known to support tumor growth and metastasis, increase mammosphere formation. RESULTS: We found that MSC increased human mammary epithelial cell (HMEC) mammosphere formation in a dose-dependent manner. A similar increase in sphere formation was seen in human inflammatory (SUM149) and non-inflammatory breast cancer cell lines (MCF-7) but not in primary inflammatory breast cancer cells (MDA-IBC-3). We determined that increased mammosphere formation can be mediated by secreted factors as MSC conditioned media from MSC spheroids significantly increased HMEC, MCF-7 and SUM149 mammosphere formation by 6.4 to 21-fold. Mammospheres grown in MSC conditioned media had lower levels of the cell adhesion protein, E-cadherin, and increased expression of N-cadherin in SUM149 and HMEC cells, characteristic of a pro-invasive mesenchymal phenotype. Co-injection with MSC in vivo resulted in a reduced latency time to develop detectable MCF-7 and MDA-IBC-3 tumors and increased the growth of MDA-IBC-3 tumors. Furthermore, E-cadherin expression was decreased in MDA-IBC-3 xenografts with co-injection of MSC. CONCLUSIONS: MSC increase the efficiency of primary mammosphere formation in normal and malignant breast cells and decrease E-cadherin expression, a biologic event associated with breast cancer progression and resistance to therapy.
Assuntos
Neoplasias da Mama/patologia , Mama/citologia , Mama/patologia , Caderinas/metabolismo , Técnicas de Cultura de Células/métodos , Células-Tronco Mesenquimais/metabolismo , Animais , Mama/metabolismo , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Transformação Celular Neoplásica , Meios de Cultivo Condicionados/farmacologia , Regulação da Expressão Gênica , Humanos , Glândulas Mamárias Humanas/citologia , Glândulas Mamárias Humanas/patologia , Camundongos , Metástase NeoplásicaRESUMO
The ability to prospectively isolate breast cancer cells that initiate tumors when transplanted orthotopically into immunocompromised mice has led to an explosion of work characterizing these cells and establishing ways to target them. Microarray studies screening for novel targets and chemical library screens for effective therapies have implicated signaling pathways, tumor-stromal interactions, miRNAs and possible even piwi-interacting (piRNAs) in the regulation of tumor initiating cell self-renewal. Potential targeting agents including the ß-catenin inhibitor sulforaphane, AKT inhibitor perfosine, hedgehog inhibitor cyclopamine, stromal interaction inhibitor repertaxin, multidrug resistance pump poison dofequifar fumarate, as well as targeted the dual epidermal growth factor family inhibitor lapatinib and many more have all been found to have toxicity against purportedly chemotherapy resistant subpopulations of cancer cells often referred to as tumor initiating cells (TICs). Work using clinical samples is emerging and supports the hypothesis that neoadjuvant chemotherapy can enrich for TICs in residual disease, but strong correlation with long-term outcome is yet to be established. This paper reviews current attempts to targeting TICs and discusses the competing hypotheses to explain breast cancer recurrence and therapy resistance.
Assuntos
Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Resistencia a Medicamentos Antineoplásicos , Células-Tronco Neoplásicas/patologia , Animais , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Mama/patologia , Progressão da Doença , Avaliação Pré-Clínica de Medicamentos , Feminino , Humanos , Camundongos , Terapia Neoadjuvante , Recidiva Local de Neoplasia , Neoplasias/tratamento farmacológico , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/fisiologiaRESUMO
BACKGROUND: Since the first suggestion of prospectively identifiable cancer stem cells in solid tumors, efforts have been made to characterize reported cancer stem cell surrogates in existing cancer cell lines, and cell lines rich with these surrogates have been used to screen for cancer stem cell targeted agents. Although 293T cells were derived from human embryonic kidney, transplantation of these cells into the mammary fat pad yields aggressive tumors that self-renew as evidenced by serial xenograft passages through transplantation. Herein we fully characterize cancer stem cell-like features in 293T human embryonic kidney cells. RESULTS: 293T cells can be readily cultured and passaged as spheres in serum-free stem cell promoting culture conditions. Cells cultured in vitro as three-dimensional spheres (3D) were shown to contain higher ALDH1 and CD44+/CD24- population compared to monolayer cells. These cells were also resistant to radiation and upregulate stem cell survival signaling including beta-catenin, Notch1 and Survivin in response to radiation. Moreover, 3D spheres generated from the 293T cells have increased expression of mesenchymal genes including vimentin, n-cadherin, zeb1, snail and slug as well as pro-metastatic genes RhoC, Tenascin C and MTA1. In addition, microRNAs implicated in self-renewal and metastases were markedly reduced in 3D spheres. CONCLUSIONS: 293T cells exhibit a cancer stem cell-like phenotype when cultured as 3D spheres and represent an important research tool for studying the molecular and biological mechanisms of cancer stem cells and for testing and developing novel targets for cancer therapy.
Assuntos
Rim/embriologia , Neoplasias/patologia , Células-Tronco Neoplásicas/patologia , Linhagem Celular , Meios de Cultura Livres de Soro , Humanos , Rim/citologia , MicroRNAs/genética , Metástase Neoplásica/patologia , Estudos Prospectivos , Regulação para CimaRESUMO
Recent studies have suggested that a specific small population of cells termed tumor-initiating cells (TICs) may be intrinsically resistant to therapy including radiation, and may therefore be the primary mediators of recurrence. Numerous targets are being explored using multiple approaches for their involvement in the self-renewal or survival as well as radioresistance of breast TICs. These studies will provide a broad range of compounds to be tested and to develop novel TIC radiosensitizers that will improve clinical outcome and decrease recurrence of cancer after radiation. In this review we will discuss recent efforts to identify and target these cells to selectively radiosensitize them with novel agents, as well as the TIC radiosensitizing potential of current therapies already in clinical use.
Assuntos
Antineoplásicos/administração & dosagem , Neoplasias da Mama/radioterapia , Sistemas de Liberação de Medicamentos/métodos , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/efeitos da radiação , Animais , Antineoplásicos/farmacologia , Neoplasias da Mama/patologia , Neoplasias da Mama/prevenção & controle , Terapia Combinada/métodos , Terapia Combinada/tendências , Feminino , Humanos , Comunicação Interdisciplinar , Modelos Biológicos , Células-Tronco Neoplásicas/patologia , Tolerância a Radiação/efeitos dos fármacos , Radiossensibilizantes/administração & dosagem , Radiossensibilizantes/farmacologiaRESUMO
We have developed a novel, reproducible, and facile methodology for the construction of artificial lipid envelopes for adenoviruses (Ad) by self-assembly of lipid molecules around the viral capsid. No alteration of the viral genome or conjugation surface chemistry at the virus capsid was necessary, therefore difficulties in production and purification associated with generating most surface-modified viruses can be eliminated. Different lipid bilayer compositions produced artificially enveloped Ad with physicochemical and biological characteristics determined by the type of lipid used. Physicochemical characteristics such as vector size, degree of aggregation, stability, and surface charge of the artificially enveloped Ad were correlated to their biological (gene transfer) function. In monolayer cell cultures, binding to the coxsackie and adenovirus receptor (CAR) was blocked using a zwitterionic envelope, whereas enhanced binding to the cell membrane was achieved using a cationic envelope. Envelopment of Ad by both zwitterionic and cationic lipid bilayers led to almost complete ablation of gene expression in cell monolayers, due to blockage of virion endosomal escape. Alternatively, artificial Ad envelopes built from lipid bilayers at the fluid phase in physiological conditions led to enhanced penetration of the vectors inside a three-dimensional tumor spheroid cell culture model and delayed gene expression in the tumor spheroid compared to nonenveloped adenovirus. These results indicate that construction of artificial envelopes for nonenveloped viruses by lipid bilayer wrapping of the viral capsids constitutes a general strategy to rationally engineer viruses at the nanoscale with control over their biological properties.