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1.
Cell ; 178(4): 807-819.e21, 2019 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-31398338

RESUMO

The NRF2 transcription factor controls a cell stress program that is implicated in cancer and there is great interest in targeting NRF2 for therapy. We show that NRF2 activity depends on Fructosamine-3-kinase (FN3K)-a kinase that triggers protein de-glycation. In its absence, NRF2 is extensively glycated, unstable, and defective at binding to small MAF proteins and transcriptional activation. Moreover, the development of hepatocellular carcinoma triggered by MYC and Keap1 inactivation depends on FN3K in vivo. N-acetyl cysteine treatment partially rescues the effects of FN3K loss on NRF2 driven tumor phenotypes indicating a key role for NRF2-mediated redox balance. Mass spectrometry reveals that other proteins undergo FN3K-sensitive glycation, including translation factors, heat shock proteins, and histones. How glycation affects their functions remains to be defined. In summary, our study reveals a surprising role for the glycation of cellular proteins and implicates FN3K as targetable modulator of NRF2 activity in cancer.


Assuntos
Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Animais , Carcinoma Hepatocelular/patologia , Feminino , Técnicas de Silenciamento de Genes , Glucose/metabolismo , Glicosilação , Células HEK293 , Células Hep G2 , Xenoenxertos , Humanos , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Neoplasias Hepáticas/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Camundongos Nus , Camundongos SCID , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Transdução Genética
2.
NMR Biomed ; 36(10): e4989, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37336778

RESUMO

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related deaths. Imaging plays a crucial role in the early detection of HCC, although current methods are limited in their ability to characterize liver lesions. Most recently, deuterium metabolic imaging (DMI) has been demonstrated as a powerful technique for the imaging of metabolism in vivo. Here, we assess the metabolic flux of [6,6'-2 H2 ] fructose in cell cultures and in subcutaneous mouse models at 9.4 T. We compare these rates with the most widely used DMI probe, [6,6'-2 H2 ] glucose, exploring the possibility of developing 2 H fructose to overcome the limitations of glucose as a novel DMI probe for detecting liver tumors. Comparison of the in vitro metabolic rates implies their similar glycolytic metabolism in the TCA cycle due to comparable production rates of 2 H glutamate/glutamine (glx) for the two precursors, but overall higher glycolytic metabolism from 2 H glucose because of a higher production rate of 2 H lactate. In vivo kinetic studies suggest that HDO can serve as a robust reporter for the consumption of the precursors in liver tumors. As fructose is predominantly metabolized in the liver, deuterated water (HDO) produced from 2 H fructose is probably less contaminated from whole-body metabolism in comparison with glucose. Moreover, in studies of the normal liver, 2 H fructose is readily converted to 2 H glx, enabling the characterization of 2 H fructose kinetics. This overcomes a major limitation of previous 2 H glucose studies in the liver, which were unable to confidently discern metabolic flux due to overlapped signals of 2 H glucose and its metabolic product, 2 H glycogen. This suggests a unique role for 2 H fructose metabolism in HCC and the normal liver, making it a useful approach for assessing liver-related diseases and the progression to oncogenesis.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Camundongos , Animais , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/metabolismo , Deutério/metabolismo , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/metabolismo , Cinética , Frutose/metabolismo , Glucose/metabolismo , Fígado/diagnóstico por imagem , Fígado/metabolismo , Ácido Láctico/metabolismo
3.
Cell Metab ; 36(6): 1394-1410.e12, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38838644

RESUMO

A vexing problem in mitochondrial medicine is our limited capacity to evaluate the extent of brain disease in vivo. This limitation has hindered our understanding of the mechanisms that underlie the imaging phenotype in the brain of patients with mitochondrial diseases and our capacity to identify new biomarkers and therapeutic targets. Using comprehensive imaging, we analyzed the metabolic network that drives the brain structural and metabolic features of a mouse model of pyruvate dehydrogenase deficiency (PDHD). As the disease progressed in this animal, in vivo brain glucose uptake and glycolysis increased. Propionate served as a major anaplerotic substrate, predominantly metabolized by glial cells. A combination of propionate and a ketogenic diet extended lifespan, improved neuropathology, and ameliorated motor deficits in these animals. Together, intermediary metabolism is quite distinct in the PDHD brain-it plays a key role in the imaging phenotype, and it may uncover new treatments for this condition.


Assuntos
Encéfalo , Glucose , Propionatos , Doença da Deficiência do Complexo de Piruvato Desidrogenase , Animais , Doença da Deficiência do Complexo de Piruvato Desidrogenase/metabolismo , Encéfalo/metabolismo , Encéfalo/diagnóstico por imagem , Glucose/metabolismo , Propionatos/metabolismo , Camundongos , Dieta Cetogênica , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças , Masculino , Glicólise
4.
J Exp Med ; 221(10)2024 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-39235528

RESUMO

The translocation t(14;18) activates BCL2 and is considered the initiating genetic lesion in most follicular lymphomas (FL). Surprisingly, FL patients fail to respond to the BCL2 inhibitor, Venetoclax. We show that mutations and deletions affecting the histone lysine methyltransferase SETD1B (KMT2G) occur in 7% of FLs and 16% of diffuse large B cell lymphomas (DLBCL). Deficiency in SETD1B confers striking resistance to Venetoclax and an experimental MCL-1 inhibitor. SETD1B also acts as a tumor suppressor and cooperates with the loss of KMT2D in lymphoma development in vivo. Consistently, loss of SETD1B in human lymphomas typically coincides with loss of KMT2D. Mechanistically, SETD1B is required for the expression of several proapoptotic BCL2 family proteins. Conversely, inhibitors of the KDM5 histone H3K4 demethylases restore BIM and BIK expression and synergize with Venetoclax in SETD1B-deficient lymphomas. These results establish SETD1B as an epigenetic regulator of cell death and reveal a pharmacological strategy to augment Venetoclax sensitivity in lymphoma.


Assuntos
Apoptose , Histona-Lisina N-Metiltransferase , Mutação , Proteínas Proto-Oncogênicas c-bcl-2 , Animais , Humanos , Camundongos , Apoptose/genética , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/metabolismo , Linfoma de Células B/genética , Linfoma de Células B/patologia , Linfoma de Células B/metabolismo , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/patologia , Linfoma Difuso de Grandes Células B/metabolismo , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Sulfonamidas/farmacologia
5.
NPJ Breast Cancer ; 8(1): 96, 2022 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-35999225

RESUMO

Estrogen receptor alpha (ERα) drives mammary gland development and breast cancer (BC) growth through an evolutionarily conserved linkage of DNA binding and hormone activation functions. Therapeutic targeting of the hormone binding pocket is a widely utilized and successful strategy for breast cancer prevention and treatment. However, resistance to this endocrine therapy is frequently encountered and may occur through bypass or reactivation of ER-regulated transcriptional programs. We now identify the induction of an ERα isoform, ERα-LBD, that is encoded by an alternative ESR1 transcript and lacks the activation function and DNA binding domains. Despite lacking the transcriptional activity, ERα-LBD is found to promote breast cancer growth and resistance to the ERα antagonist fulvestrant. ERα-LBD is predominantly localized to the cytoplasm and mitochondria of BC cells and leads to enhanced glycolysis, respiration and stem-like features. Intriguingly, ERα-LBD expression and function does not appear to be restricted to cancers that express full length ERα but also promotes growth of triple-negative breast cancers and ERα-LBD transcript (ESR1-LBD) is also present in BC samples from both ERα(+) and ERα(-) human tumors. These findings point to ERα-LBD as a potential mediator of breast cancer progression and therapy resistance.

6.
Cancers (Basel) ; 13(4)2021 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-33562682

RESUMO

Inhibition of the eIF4A RNA helicase with silvestrol and related compounds is emerging as a powerful anti-cancer strategy. We find that a synthetic silvestrol analogue (CR-1-31 B) has nanomolar activity across many cancer cell lines. It is especially active against aggressive MYC+/BCL2+ B cell lymphomas and this likely reflects the eIF4A-dependent translation of both MYC and BCL2. We performed a genome-wide CRISPR/Cas9 screen and identified mechanisms of resistance to this new class of therapeutics. We identify three negative NRF2 regulators (KEAP1, CUL3, CAND1) whose inactivation is sufficient to cause CR1-31-B resistance. NRF2 is known to alter the oxidation state of translation factors and cause a broad increase in protein production. We find that NRF2 activation particularly increases the translation of some eIF4A-dependent mRNAs and restores MYC and BCL2 production. We know that NRF2 functions depend on removal of sugar adducts by the frutosamine-3-kinase (FN3K). Accordingly, loss of FN3K results in NRF2 hyper-glycation and inactivation and resensitizes cancer cells to eIF4A inhibition. Together, our findings implicate NRF2 in the translation of eIF4A-dependent mRNAs and point to FN3K inhibition as a new strategy to block NRF2 functions in cancer.

7.
Breast Cancer Res ; 12(5): R80, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20929542

RESUMO

INTRODUCTION: Tyrosine phosphorylated signal transducer and activator of transcription 3 (pStat3) is present in numerous cancers and is required for mediating tumorigenesis. Autocrine and paracrine interleukin (IL)-6 signaling is the principal mechanism by which Stat3 is persistently phosphorylated in epithelial tumors including breast, lung, colon and gastric cancer. The Ras oncogene mediates cellular transformation without evidence of pStat3 in cultured cells. Recently, however non-tyrosine phosphorylated Stat3 was shown to have a transcriptional activating function, a role in mitochondrial function and to mediate cell migration.. Here we examined the role of Stat3 in Ras mediated transformation. METHODS: Ha-rasV12 transformed mammary epithelial cells (MCF10A) cells were transduced with a Stat3shRNA, IL-6shRNA and/or treated with inhibitors of Janus kinases (JAKs) to examine the role of the IL-6 signaling pathway in Ras mediated invasion and tumorigenesis. RESULTS: Cellular migration, invasion, anchorage independent growth and tumorigenesis were largely abrogated in the Stat3-reduced cells compared to control cells. Analysis of MCF10A-Ras tumors revealed high levels of pStat3 and interleukin-6. Tumors derived from transgenic MMTV-K-Ras mice were also found to express pStat3 and IL-6. MCF10A-Ras cells, when grown in a three-dimensional Matrigel culture system revealed the appearance of the junctional protein E-Cadherin as a consequence of reducing Stat3 levels or inhibiting Stat3 activity. Decreasing IL-6 levels in the MCF10A-Ras cells abrogated tumorigenesis and reduced cell migration. By isolating Ras-expressing primary tumors and serially passaging these cells in two-dimensional culture led to a decrease in IL-6 and pStat3 levels with the reappearance of E-Cadherin. CONCLUSIONS: The cellular and environmental context can lead to differential IL-6/pStat3 signaling and a dependency on this cytokine and transcription factor for migration, invasion and tumorigenesis.


Assuntos
Transformação Celular Neoplásica/metabolismo , Interleucina-6/metabolismo , Neoplasias Mamárias Animais/metabolismo , Fator de Transcrição STAT3/metabolismo , Proteínas Ativadoras de ras GTPase/metabolismo , Animais , Caderinas/biossíntese , Linhagem Celular Transformada , Movimento Celular , Feminino , Interleucina-6/genética , Janus Quinases/antagonistas & inibidores , Neoplasias Mamárias Animais/genética , Camundongos , Invasividade Neoplásica , Fosforilação , Interferência de RNA , RNA Interferente Pequeno , Fator de Transcrição STAT3/genética , Transdução de Sinais/genética
8.
JCI Insight ; 4(12)2019 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-31217352

RESUMO

Inhibition of Bruton tyrosine kinase (BTK) is a breakthrough therapy for certain B cell lymphomas and B cell chronic lymphatic leukemia. Covalent BTK inhibitors (e.g., ibrutinib) bind to cysteine C481, and mutations of this residue confer clinical resistance. This has led to the development of noncovalent BTK inhibitors that do not require binding to cysteine C481. These new compounds are now entering clinical trials. In a systematic BTK mutagenesis screen, we identify residues that are critical for the activity of noncovalent inhibitors. These include a gatekeeper residue (T474) and mutations in the kinase domain. Strikingly, co-occurrence of gatekeeper and kinase domain lesions (L512M, E513G, F517L, L547P) in cis results in a 10- to 15-fold gain of BTK kinase activity and de novo transforming potential in vitro and in vivo. Computational BTK structure analyses reveal how these lesions disrupt an intramolecular mechanism that attenuates BTK activation. Our findings anticipate clinical resistance mechanisms to a new class of noncovalent BTK inhibitors and reveal intramolecular mechanisms that constrain BTK's transforming potential.


Assuntos
Tirosina Quinase da Agamaglobulinemia/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Tirosina Quinase da Agamaglobulinemia/genética , Tirosina Quinase da Agamaglobulinemia/metabolismo , Animais , Sítios de Ligação , Linhagem Celular , Transformação Celular Neoplásica , Cisteína/metabolismo , Células HEK293 , Humanos , Camundongos , Mutagênese , Domínios Proteicos , Relação Estrutura-Atividade
9.
Cancer Res ; 66(5): 2544-52, 2006 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-16510571

RESUMO

Signal transducers and activators of transcription 3 (STAT3) is a transcription factor that is aberrantly activated in many cancer cells. Constitutively activated STAT3 is oncogenic, presumably as a consequence of the genes that it differentially regulates. Activated STAT3 correlated with elevated cyclin D1 protein in primary breast tumors and breast cancer-derived cell lines. Cyclin D1 mRNA levels were increased in primary rat-, mouse-, and human-derived cell lines expressing either the oncogenic variant of STAT3 (STAT3-C) or vSrc, which constitutively phosphorylates STAT3. Mutagenesis of STAT3 binding sites within the cyclin D1 promoter and chromatin immunoprecipitation studies showed an association between STAT3 and the transcriptional regulation of the human cyclin D1 gene. Introduction of STAT3-C and vSrc into immortalized cyclin D1(-/-) and cyclin D1(-/+) fibroblasts led to anchorage-independent growth of only cyclin D1(-/+) cells. Furthermore, knockdown of cyclin D1 in breast carcinoma cells led to a reduction in anchorage-independent growth. Phosphorylation of the retinoblastoma (Rb) protein [a target of the cyclin D1/cyclin-dependent kinase 4/6 (cdk4/6) holoenzyme] was delayed in the cyclin D1(-/-) cells relative to cyclin D1(-/+) cells. The E7 oncogene, whose activity includes degradation of Rb and dissociation of Rb from E2F, did not confer anchorage-independent growth to the cyclin D1(-/-) cells but, in conjunction with vSrc, resulted in robust growth in soft agar. These results suggest both a cdk-dependent and cdk-independent role for cyclin D1 in modulating transformation by different oncogenes.


Assuntos
Transformação Celular Neoplásica/genética , Ciclina D1/biossíntese , Fator de Transcrição STAT3/metabolismo , Animais , Sítios de Ligação , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Adesão Celular/genética , Processos de Crescimento Celular/genética , Linhagem Celular Tumoral , Ciclina D1/genética , Fase G1/genética , Humanos , Luciferases/genética , Luciferases/metabolismo , Camundongos , Mutagênese Sítio-Dirigida , Células NIH 3T3 , Proteínas E7 de Papillomavirus/genética , Regiões Promotoras Genéticas , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , RNA Interferente Pequeno/genética , Ratos , Fator de Transcrição STAT3/genética , Ativação Transcricional
10.
Breast Cancer Res ; 9(3): R32, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17531096

RESUMO

INTRODUCTION: Signal transducer and activator of transcription 3 (Stat3) is constitutively tyrosine-phosphorylated in approximately 50% of primary breast carcinomas. A number of different mechanisms responsible for Stat3 activation, including abnormal activation of receptor tyrosine kinases, Src, and Janus kinases (Jaks), have been implicated in breast cancer. METHODS: We examined six breast cancer-derived cell lines expressing high or low levels of tyrosine-phosphorylated Stat3 (pStat3) as well as primary breast cancer specimens. RESULTS: Inhibition of Src or EGFR (epidermal growth factor receptor) tyrosine kinases had no effect on pStat3 levels, whereas pan-Jak inhibitor P6 resulted in complete abrogation of Stat3 phosphorylation and inhibition of growth. Jaks are required for cytokine signaling, and the glycoprotein 130 (gp130) receptor-associated Jaks are known mediators of Stat3 phosphorylation. Blockade of the gp130 receptor or sequestration of the interleukin-6 (IL-6) ligand led to a decrease of pStat3 levels. Conditioned media from those cell lines expressing high levels of pStat3 contained IL-6 and were capable of stimulating Stat3 phosphorylation. We examined IL-6 levels in primary breast tumors and found a positive correlation between pStat3 and IL-6 expression. CONCLUSION: In summary, a principal mechanism of Stat3 activation in breast cancer is through the IL-6/gp130/Jak pathway.


Assuntos
Neoplasias da Mama/metabolismo , Glicoproteínas/fisiologia , Interleucina-6/fisiologia , Janus Quinases/metabolismo , Fator de Transcrição STAT3/metabolismo , Linhagem Celular Tumoral , Ensaio de Imunoadsorção Enzimática , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Fosfotirosina/metabolismo , Fator de Transcrição STAT3/genética
11.
Cancer Res ; 77(8): 1927-1941, 2017 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-28202520

RESUMO

The hypothesis that microvesicle-mediated miRNA transfer converts noncancer stem cells into cancer stem cells (CSC) leading to therapy resistance remains poorly investigated. Here we provide direct evidence supporting this hypothesis, by demonstrating how microvesicles derived from cancer-associated fibroblasts (CAF) transfer miR-221 to promote hormonal therapy resistance (HTR) in models of luminal breast cancer. We determined that CAF-derived microvesicles horizontally transferred miR-221 to tumor cells and, in combination with hormone therapy, activated an ERlo/Notchhi feed-forward loop responsible for the generation of CD133hi CSCs. Importantly, microvesicles from patients with HTR metastatic disease expressed high levels of miR-221. We further determined that the IL6-pStat3 pathway promoted the biogenesis of onco-miR-221hi CAF microvesicles and established stromal CSC niches in experimental and patient-derived breast cancer models. Coinjection of patient-derived CAFs from bone metastases led to de novo HTR tumors, which was reversed with IL6R blockade. Finally, we generated patient-derived xenograft (PDX) models from patient-derived HTR bone metastases and analyzed tumor cells, stroma, and microvesicles. Murine and human CAFs were enriched in HTR tumors expressing high levels of CD133hi cells. Depletion of murine CAFs from PDX restored sensitivity to HT, with a concurrent reduction of CD133hi CSCs. Conversely, in models of CD133neg, HT-sensitive cancer cells, both murine and human CAFs promoted de novo HT resistance via the generation of CD133hi CSCs that expressed low levels of estrogen receptor alpha. Overall, our results illuminate how microvesicle-mediated horizontal transfer of genetic material from host stromal cells to cancer cells triggers the evolution of therapy-resistant metastases, with potentially broad implications for their control. Cancer Res; 77(8); 1927-41. ©2017 AACR.


Assuntos
Antineoplásicos Hormonais/farmacologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Micropartículas Derivadas de Células/patologia , Células-Tronco Neoplásicas/patologia , Células Estromais/patologia , Animais , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Fibroblastos Associados a Câncer , Estudos de Casos e Controles , Micropartículas Derivadas de Células/genética , Micropartículas Derivadas de Células/metabolismo , Resistencia a Medicamentos Antineoplásicos , Estradiol/análogos & derivados , Estradiol/farmacologia , Feminino , Fulvestranto , Células HeLa , Xenoenxertos , Humanos , Interleucina-6/metabolismo , Células MCF-7 , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , MicroRNAs/administração & dosagem , MicroRNAs/genética , Neoplasias Hormônio-Dependentes/genética , Neoplasias Hormônio-Dependentes/metabolismo , Neoplasias Hormônio-Dependentes/patologia , Células-Tronco Neoplásicas/metabolismo , Fator de Transcrição STAT3/metabolismo , Células Estromais/metabolismo
12.
Nat Commun ; 7: 10442, 2016 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-26858125

RESUMO

The mechanisms of metastatic progression from hormonal therapy (HT) are largely unknown in luminal breast cancer. Here we demonstrate the enrichment of CD133(hi)/ER(lo) cancer cells in clinical specimens following neoadjuvant endocrine therapy and in HT refractory metastatic disease. We develop experimental models of metastatic luminal breast cancer and demonstrate that HT can promote the generation of HT-resistant, self-renewing CD133(hi)/ER(lo)/IL6(hi) cancer stem cells (CSCs). HT initially abrogates oxidative phosphorylation (OXPHOS) generating self-renewal-deficient cancer cells, CD133(hi)/ER(lo)/OXPHOS(lo). These cells exit metabolic dormancy via an IL6-driven feed-forward ER(lo)-IL6(hi)-Notch(hi) loop, activating OXPHOS, in the absence of ER activity. The inhibition of IL6R/IL6-Notch pathways switches the self-renewal of CD133(hi) CSCs, from an IL6/Notch-dependent one to an ER-dependent one, through the re-expression of ER. Thus, HT induces an OXPHOS metabolic editing of luminal breast cancers, paradoxically establishing HT-driven self-renewal of dormant CD133(hi)/ER(lo) cells mediating metastatic progression, which is sensitive to dual targeted therapy.


Assuntos
Antineoplásicos Hormonais , Neoplasias Ósseas/genética , Neoplasias da Mama/genética , Carcinoma Ductal de Mama/genética , Carcinoma Lobular/genética , Autorrenovação Celular/genética , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica , Células-Tronco Neoplásicas/metabolismo , Antígeno AC133 , Anastrozol , Androstadienos , Animais , Antígenos CD/metabolismo , Neoplasias Ósseas/secundário , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/secundário , Carcinoma Lobular/secundário , Linhagem Celular Tumoral , Estradiol/análogos & derivados , Feminino , Citometria de Fluxo , Fulvestranto , Glicoproteínas/metabolismo , Humanos , Técnicas In Vitro , Interleucina-6/genética , Letrozol , Leuprolida , Células MCF-7 , Camundongos Endogâmicos NOD , Camundongos SCID , Metástase Neoplásica , Transplante de Neoplasias , Nitrilas , Fosforilação Oxidativa , Peptídeos/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Receptor Notch3 , Receptores de Estrogênio/metabolismo , Receptores Notch/genética , Transdução de Sinais/genética , Tamoxifeno , Triazóis
13.
Neoplasia ; 15(7): 848-62, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23814496

RESUMO

We have investigated the importance of interleukin-6 (IL-6) in promoting tumor growth and metastasis. In human primary breast cancers, increased levels of IL-6 were found at the tumor leading edge and positively correlated with advanced stage, suggesting a mechanistic link between tumor cell production of IL-6 and invasion. In support of this hypothesis, we showed that the IL-6/Janus kinase (JAK)/signal transducer and activator of transcription 3 (Stat3) pathway drives tumor progression through the stroma and metastatic niche. Overexpression of IL-6 in tumor cell lines promoted myeloid cell recruitment, angiogenesis, and induced metastases. We demonstrated the therapeutic potential of interrupting this pathway with IL-6 receptor blockade or by inhibiting its downstream effectors JAK1/2 or Stat3. These clinically relevant interventions did not inhibit tumor cell proliferation in vitro but had profound effects in vivo on tumor progression, interfering broadly with tumor-supportive stromal functions, including angiogenesis, fibroblast infiltration, and myeloid suppressor cell recruitment in both the tumor and pre-metastatic niche. This study provides the first evidence for IL-6 expression at the leading edge of invasive human breast tumors and demonstrates mechanistically that IL-6/JAK/Stat3 signaling plays a critical and pharmacologically targetable role in orchestrating the composition of the tumor microenvironment that promotes growth, invasion, and metastasis.


Assuntos
Transformação Celular Neoplásica/metabolismo , Interleucina-6/metabolismo , Janus Quinase 3/metabolismo , Neoplasias/metabolismo , Neoplasias/patologia , Fator de Transcrição STAT3/metabolismo , Animais , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Transformação Celular Neoplásica/genética , Feminino , Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Interleucina-6/genética , Janus Quinase 3/antagonistas & inibidores , Janus Quinase 3/genética , Camundongos , Camundongos Knockout , Metástase Neoplásica , Neoplasias/genética , Pirazóis/farmacologia , Pirimidinas/farmacologia , Fator de Transcrição STAT3/genética , Transdução de Sinais/efeitos dos fármacos , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/genética
14.
PLoS One ; 6(11): e27851, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22140473

RESUMO

We determined that signal transducer and activator of transcription 3 (Stat3) is tyrosine phosphorylated in 37% of primary breast tumors and 63% of paired metastatic axillary lymph nodes. Examination of the distribution of tyrosine phosphorylated (pStat3) in primary tumors revealed heterogenous expression within the tumor with the highest levels found in cells on the edge of tumors with relatively lower levels in the central portion of tumors. In order to determine Stat3 target genes that may be involved in migration and metastasis, we identified those genes that were differentially expressed in primary breast cancer samples as a function of pStat3 levels. In addition to known Stat3 transcriptional targets (Twist, Snail, Tenascin-C and IL-8), we identified ENPP2 as a novel Stat3 regulated gene, which encodes autotaxin (ATX), a secreted lysophospholipase which mediates mammary tumorigenesis and cancer cell migration. A positive correlation between nuclear pStat3 and ATX was determined by immunohistochemical analysis of primary breast cancer samples and matched axillary lymph nodes and in several breast cancer derived cell lines. Inhibition of pStat3 or reducing Stat3 expression led to a decrease in ATX levels and cell migration. An association between Stat3 and the ATX promoter, which contains a number of putative Stat3 binding sites, was determined by chromatin immunoprecipitation. These observations suggest that activated Stat3 may regulate the migration of breast cancer cells through the regulation of ATX.


Assuntos
Neoplasias da Mama/metabolismo , Diester Fosfórico Hidrolases/metabolismo , Fator de Transcrição STAT3/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Análise por Conglomerados , Feminino , Regulação Neoplásica da Expressão Gênica , Genes Neoplásicos/genética , Humanos , Linfonodos/metabolismo , Linfonodos/patologia , Metástase Neoplásica , Fosforilação , Fosfotirosina/metabolismo
15.
Cancer Res ; 66(19): 9714-21, 2006 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-17018630

RESUMO

Interleukin-6 (IL-6) and the subsequent Janus-activated kinase (JAK)-dependent signaling pathways play a critical role in the pathogenesis of multiple myeloma. Here, we compared the sensitivity and specificity of a novel pan-JAK inhibitor, tetracyclic pyridone 6 (P6), with that of AG490 in a panel of myeloma-derived cell lines. P6 induced growth arrest and subsequent apoptosis of the IL-6-dependent hybridoma and myeloma-derived cell lines (B9 and INA-6) grown either in IL-6-containing medium or in the presence of bone marrow-derived stromal cells (BMSC) using much lower concentrations of drug and with significantly faster kinetics than AG490. Myeloma-derived cell lines, which either express constitutively activated JAK/signal transducers and activators of transcription (STAT) 3 (U266) or are IL-6 growth stimulated (KMS11), are partially growth inhibited by P6. However, P6 does not inhibit the growth of myeloma-derived cell lines lacking activated JAKs/STATs nor does it inhibit mitogen-activated protein kinase/extracellular signal-regulated kinase (ERK) kinase activity compared with AG490, which led to activation of ERK and induced robust apoptosis of all the examined cell lines. Finally, P6 inhibited the growth of primary myeloma patient samples grown in the presence of BMSCs. Thus, P6 is a more sensitive and specific inhibitor of JAK-STAT3 activity compared with AG490 and potently inhibited the growth of primary myeloma cells and myeloma-derived cell lines grown on BMSCs.


Assuntos
Benzimidazóis/farmacologia , Janus Quinases/antagonistas & inibidores , Mieloma Múltiplo/patologia , Proteínas de Neoplasias/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Piridonas/farmacologia , Animais , Linhagem Celular Tumoral/citologia , Linhagem Celular Tumoral/efeitos dos fármacos , Técnicas de Cocultura , Ensaios de Seleção de Medicamentos Antitumorais , Ativação Enzimática , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Humanos , Hibridomas/efeitos dos fármacos , Hibridomas/patologia , Interleucina-6/farmacologia , Janus Quinases/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Proteínas de Neoplasias/metabolismo , Fosforilação/efeitos dos fármacos , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Fator de Transcrição STAT3/metabolismo , Células Estromais/fisiologia , Tirfostinas/farmacologia
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