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1.
J Biol Chem ; 293(34): 13284-13296, 2018 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-29980600

RESUMO

Small nucleolar RNAs (snoRNAs) are noncoding RNAs that guide chemical modifications of structural RNAs. Whereas snoRNAs primarily localize in the nucleolus, where their canonical function is to target nascent ribosomal RNAs for 2'-O-methylation, recent studies provide evidence that snoRNAs traffic out of the nucleus. Furthermore, RNA-Seq data indicate that extracellular vesicles released from cells contain snoRNAs. However, it is not known whether snoRNA secretion is regulated or whether secreted snoRNAs are functional. Here, we show that inflammation stimulates secretion of Rpl13a snoRNAs U32a (SNORD32a), U33 (SNORD33), U34 (SNORD34), and U35a (SNORD35a) from cultured macrophages, in mice, and in human subjects. Secreted snoRNAs co-fractionate with extracellular vesicles and are taken up by recipient cells. In a murine parabiosis model, we demonstrate that snoRNAs travel through the circulation to function in distant tissues. These findings support a previously unappreciated link between inflammation and snoRNA secretion in mice and humans and uncover a potential role for secreted snoRNAs in cell-cell communication.


Assuntos
Nucléolo Celular/metabolismo , Núcleo Celular/metabolismo , Processamento Pós-Transcricional do RNA , RNA Ribossômico/química , RNA Nucleolar Pequeno/metabolismo , Proteínas Ribossômicas/fisiologia , Animais , Transporte Biológico , Nucléolo Celular/genética , Núcleo Celular/genética , Feminino , Humanos , Masculino , Metilação , Camundongos , Camundongos Knockout , RNA Ribossômico/metabolismo , RNA Nucleolar Pequeno/genética
2.
Nature ; 486(7403): 353-60, 2012 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-22722193

RESUMO

To correlate the variable clinical features of oestrogen-receptor-positive breast cancer with somatic alterations, we studied pretreatment tumour biopsies accrued from patients in two studies of neoadjuvant aromatase inhibitor therapy by massively parallel sequencing and analysis. Eighteen significantly mutated genes were identified, including five genes (RUNX1, CBFB, MYH9, MLL3 and SF3B1) previously linked to haematopoietic disorders. Mutant MAP3K1 was associated with luminal A status, low-grade histology and low proliferation rates, whereas mutant TP53 was associated with the opposite pattern. Moreover, mutant GATA3 correlated with suppression of proliferation upon aromatase inhibitor treatment. Pathway analysis demonstrated that mutations in MAP2K4, a MAP3K1 substrate, produced similar perturbations as MAP3K1 loss. Distinct phenotypes in oestrogen-receptor-positive breast cancer are associated with specific patterns of somatic mutations that map into cellular pathways linked to tumour biology, but most recurrent mutations are relatively infrequent. Prospective clinical trials based on these findings will require comprehensive genome sequencing.


Assuntos
Inibidores da Aromatase/uso terapêutico , Aromatase/metabolismo , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Genoma Humano/genética , Anastrozol , Androstadienos/farmacologia , Androstadienos/uso terapêutico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Reparo do DNA , Exoma/genética , Éxons/genética , Feminino , Variação Genética/genética , Humanos , Letrozol , MAP Quinase Quinase 4/genética , MAP Quinase Quinase Quinase 1/genética , Mutação/genética , Nitrilas/farmacologia , Nitrilas/uso terapêutico , Receptores de Estrogênio/metabolismo , Resultado do Tratamento , Triazóis/farmacologia , Triazóis/uso terapêutico
3.
Nature ; 464(7291): 999-1005, 2010 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-20393555

RESUMO

Massively parallel DNA sequencing technologies provide an unprecedented ability to screen entire genomes for genetic changes associated with tumour progression. Here we describe the genomic analyses of four DNA samples from an African-American patient with basal-like breast cancer: peripheral blood, the primary tumour, a brain metastasis and a xenograft derived from the primary tumour. The metastasis contained two de novo mutations and a large deletion not present in the primary tumour, and was significantly enriched for 20 shared mutations. The xenograft retained all primary tumour mutations and displayed a mutation enrichment pattern that resembled the metastasis. Two overlapping large deletions, encompassing CTNNA1, were present in all three tumour samples. The differential mutation frequencies and structural variation patterns in metastasis and xenograft compared with the primary tumour indicate that secondary tumours may arise from a minority of cells within the primary tumour.


Assuntos
Neoplasias Encefálicas/genética , Neoplasias Encefálicas/secundário , Neoplasias da Mama/genética , Genoma Humano/genética , Mutação/genética , Transplante de Neoplasias , Adulto , Neoplasias da Mama/patologia , Variações do Número de Cópias de DNA/genética , Análise Mutacional de DNA , Progressão da Doença , Feminino , Frequência do Gene/genética , Genômica , Humanos , Translocação Genética/genética , Transplante Heterólogo , alfa Catenina/genética
4.
Cancer Cell ; 6(2): 103-4, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15324690

RESUMO

Women with ErbB2-positive breast cancer have a poor prognosis, and frequently, chemotherapy treatment is ineffective. The ErbB2-targeted antibody trastuzumab improves survival when given with chemotherapy to patients with ErbB2-overexpressing metastatic disease, but treatment is not curative, and primary resistance is common. Postulated mechanisms of action for trastuzumab include immune-mediated cytotoxicity and receptor downmodulation. A study in this issue of Cancer Cell suggests that trastuzumab causes rapid activation of the PTEN lipid phosphatase, which in turn downregulates the phosphatidylinositol 3'-kinase (PI3K) pathway. Resistance to trastuzumab occurs when PTEN function is lost, suggesting that PTEN activation is a critical component of the therapeutic effect.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Monoéster Fosfórico Hidrolases/metabolismo , Receptor ErbB-2/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Anticorpos Monoclonais/metabolismo , Anticorpos Monoclonais Humanizados , Antineoplásicos/metabolismo , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/metabolismo , Ativação Enzimática , Feminino , Genes Supressores de Tumor , Humanos , PTEN Fosfo-Hidrolase , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais/fisiologia , Trastuzumab
5.
Breast Cancer Res ; 13(2): R21, 2011 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-21362200

RESUMO

INTRODUCTION: Inhibition of phosphatidylinositol-3-kinase (PI3K) induces apoptosis when combined with estrogen deprivation in estrogen receptor (ER)-positive breast cancer. The aims of the present study were to identify effective PI3K pathway inhibitor and endocrine therapy combinations, to evaluate the effect of PI3K pathway mutations and estrogen dependency on tumor response, and to determine the relevance of PIK3CA mutation in recurrent disease. METHODS: The PI3K catalytic subunit inhibitor BKM120, the mammalian target of rapamycin (mTOR) inhibitor RAD001 and the dual PI3K/mTOR inhibitor BGT226 were tested against ER-positive breast cancer cell lines before and after long-term estrogen deprivation (LTED). The impact of estradiol deprivation and the ER downregulator fulvestrant on PI3K pathway inhibitor-induced apoptosis was assessed. PIK3CA hotspot mutation analysis was performed in 51 recurrent or metastatic breast cancers and correlated with ER status and survival. RESULTS: Drug-induced apoptosis was most marked in short-term estrogen-deprived cells with PIK3CA mutation and phosphatase and tensin homolog loss. Apoptosis was most highly induced by BGT226, followed by BKM120, and then RAD001. Estradiol antagonized PI3K inhibitor-induced apoptosis following short-term estrogen deprivation, emphasizing a role for estrogen-deprivation therapy in promoting PI3K inhibitor activity in the first-line setting. ER-positive MCF7 LTED cells exhibited relative resistance to PI3K pathway inhibition that was reversed by fulvestrant. In contrast, T47D LTED cells exhibited ER loss and ER-independent PI3K agent sensitivity. PIK3CA mutation was prevalent in relapsed ER-positive disease (48%) and was associated with persistent ER positivity and a late relapse pattern. CONCLUSIONS: Estrogen deprivation increased the apoptotic effects of PI3K and dual PI3K/mTOR inhibitors in ER-positive disease, providing a rationale for PI3K/aromatase inhibitor combinations as first-line therapy. In LTED cells, differential effects on ER expression may be a relevant consideration. When ER was persistently expressed, fulvestrant strongly promoted PI3K drug activity. When ER was lost, PI3K inhibitor monotherapy was sufficient to induce high-level apoptosis. Although tumors with PIK3CA mutation had a late recurrence pattern, these mutations were common in metastatic disease and were most often associated with persistent ER expression. Targeting PIK3CA mutant tumors with a PI3K pathway inhibitor and fulvestrant is therefore a feasible strategy for aromatase-inhibitor-resistant ER-positive relapsed breast cancer.


Assuntos
Antineoplásicos Hormonais/farmacologia , Neoplasias da Mama/tratamento farmacológico , Inibidores de Fosfoinositídeo-3 Quinase , Receptores de Estrogênio/metabolismo , Aminopiridinas/farmacologia , Apoptose/efeitos dos fármacos , Inibidores da Aromatase/farmacologia , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Classe I de Fosfatidilinositol 3-Quinases , Estradiol/análogos & derivados , Estradiol/metabolismo , Estradiol/farmacologia , Estrogênios/metabolismo , Everolimo , Feminino , Fulvestranto , Humanos , Imidazóis/farmacologia , Morfolinas/farmacologia , Mutação , Recidiva Local de Neoplasia/genética , PTEN Fosfo-Hidrolase/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Quinolinas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Sirolimo/análogos & derivados , Sirolimo/farmacologia , Serina-Treonina Quinases TOR/antagonistas & inibidores
6.
Breast Cancer Res Treat ; 119(2): 379-90, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19844788

RESUMO

Mutations in the alpha catalytic subunit of phosphoinositol-3-kinase (PIK3CA) occur in approximately 30% of ER positive breast cancers. We therefore sought to determine the impact of PIK3CA mutation on response to neoadjuvant endocrine therapy. Exons 9 (helical domain) and 20 (kinase domain-KD) mutations in PIK3CA were determined samples from four neoadjuvant endocrine therapy trials.Interactions with clinical, pathological, and biomarker response parameters were examined. A weak negative interaction between PIK3CA mutation status and clinical response to neoadjuvant endocrine treatment was detected(N = 235 P < or = 0.05), but not with treatment-induced changes in Ki67-based proliferation index (N = 418). Despite these findings, PIK3CA KD mutation was a favorable prognostic factor for relapse-free survival (RFS log-rank P = 0.02) in the P024 trial (N = 153). The favorable prognostic effect was maintained in a multivariable analysis(N = 125) that included the preoperative endocrine prognostic index, an approach to predicting RFS based on post neoadjuvant endocrine therapy pathological stage, ER, and Ki67 levels (HR for no PIK3CA KD mutation, 14, CI 1.9-105 P = 0.01). PIK3CA mutation status did not strongly interact with neoadjuvant endocrine therapy responsiveness in estrogen receptor-positive breast cancer. Nonetheless, as with other recent studies, a favorable interaction between PIK3CA KD mutation and prognosis was detected. The mechanism for the favorable prognostic impact of PIK3CA mutation status therefore remains unexplained.


Assuntos
Antineoplásicos Hormonais/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Mutação , Fosfatidilinositol 3-Quinases/genética , Receptores de Estrogênio/análise , Neoplasias da Mama/química , Neoplasias da Mama/enzimologia , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Proliferação de Células/efeitos dos fármacos , Quimioterapia Adjuvante , Classe I de Fosfatidilinositol 3-Quinases , Ensaios Clínicos Fase II como Assunto , Intervalo Livre de Doença , Éxons , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Antígeno Ki-67/análise , Terapia Neoadjuvante , Estadiamento de Neoplasias , Fosforilação , Modelos de Riscos Proporcionais , Proteínas Proto-Oncogênicas c-akt/análise , Ensaios Clínicos Controlados Aleatórios como Assunto , Receptor ErbB-2/análise , Receptores de Progesterona/análise , Medição de Risco , Fatores de Tempo , Resultado do Tratamento
7.
JAMA ; 302(7): 774-80, 2009 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-19690310

RESUMO

CONTEXT: Estrogen deprivation therapy with aromatase inhibitors has been hypothesized to paradoxically sensitize hormone-receptor-positive breast cancer tumor cells to low-dose estradiol therapy. OBJECTIVE: To determine whether 6 mg of estradiol (daily) is a viable therapy for postmenopausal women with advanced aromatase inhibitor-resistant hormone receptor-positive breast cancer. DESIGN, SETTING, AND PATIENTS: A phase 2 randomized trial of 6 mg vs 30 mg of oral estradiol used daily (April 2004-February 2008 [enrollment closed]). Eligible patients (66 randomized) had metastatic breast cancer treated with an aromatase inhibitor with progression-free survival (> or = 24 wk) or relapse (after > or = 2 y) of adjuvant aromatase inhibitor use. Patients at high risk of estradiol-related adverse events were excluded. Patients were examined after 1 and 2 weeks for clinical and laboratory toxicities and flare reactions and thereafter every 4 weeks. Tumor radiological assessment occurred every 12 weeks. At least 1 measurable lesion or 4 measurable lesions (bone-only disease) were evaluated for tumor response. INTERVENTION: Randomization to receive 1 oral 2-mg generic estradiol tablet 3 times daily or five 2-mg tablets 3 times daily. MAIN OUTCOME MEASURES: Primary end point: clinical benefit rate (response plus stable disease at 24 weeks). SECONDARY OUTCOMES: toxicity, progression-free survival, time to treatment failure, quality of life, and the predictive properties of the metabolic flare reaction detected by positron emission tomography/computed tomography with fluorodeoxyglucose F 18. RESULTS: The adverse event rate (> or = grade 3) in the 30-mg group (11/32 [34%]; 95% confidence interval [CI], 23%-47%) was higher than in the 6-mg group (4/34 [18%]; 95% CI, 5%-22%; P = .03). Clinical benefit rates were 9 of 32 (28%; 95% CI, 18%-41%) in the 30-mg group and 10 of 34 (29%; 95% CI, 19%-42%) in the 6-mg group. An estradiol-stimulated increase in fluorodeoxyglucose F 18 uptake (> or = 12% prospectively defined) was predictive of response (positive predictive value, 80%; 95% CI, 61%-92%). Seven patients with estradiol-sensitive disease were re-treated with aromatase inhibitors at estradiol progression, among which 2 had partial response and 1 had stable disease, suggesting resensitization to estrogen deprivation. CONCLUSIONS: In women with advanced breast cancer and acquired resistance to aromatase inhibitors, a daily dose of 6 mg of estradiol provided a similar clinical benefit rate as 30 mg, with fewer serious adverse events. The efficacy of treatment with the lower dose should be further examined in phase 3 clinical trials. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00324259.


Assuntos
Antineoplásicos Hormonais/uso terapêutico , Inibidores da Aromatase/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Estradiol/administração & dosagem , Estrogênios/administração & dosagem , Receptores de Estrogênio/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/metabolismo , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/mortalidade , Resistencia a Medicamentos Antineoplásicos , Estradiol/uso terapêutico , Estrogênios/uso terapêutico , Feminino , Fluordesoxiglucose F18 , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons , Pós-Menopausa , Valor Preditivo dos Testes , Qualidade de Vida , Compostos Radiofarmacêuticos , Análise de Sobrevida
8.
Cell Rep ; 24(6): 1434-1444.e7, 2018 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-30089255

RESUMO

RNA sequencing (RNA-seq) detects estrogen receptor alpha gene (ESR1) fusion transcripts in estrogen receptor-positive (ER+) breast cancer, but their role in disease pathogenesis remains unclear. We examined multiple ESR1 fusions and found that two, both identified in advanced endocrine treatment-resistant disease, encoded stable and functional fusion proteins. In both examples, ESR1-e6>YAP1 and ESR1-e6>PCDH11X, ESR1 exons 1-6 were fused in frame to C-terminal sequences from the partner gene. Functional properties include estrogen-independent growth, constitutive expression of ER target genes, and anti-estrogen resistance. Both fusions activate a metastasis-associated transcriptional program, induce cellular motility, and promote the development of lung metastasis. ESR1-e6>YAP1- and ESR1-e6>PCDH11X-induced growth remained sensitive to a CDK4/6 inhibitor, and a patient-derived xenograft (PDX) naturally expressing the ESR1-e6>YAP1 fusion was also responsive. Transcriptionally active ESR1 fusions therefore trigger both endocrine therapy resistance and metastatic progression, explaining the association with fatal disease progression, although CDK4/6 inhibitor treatment is predicted to be effective.


Assuntos
Neoplasias da Mama/genética , Receptor alfa de Estrogênio/genética , Fusão Gênica/genética , Neoplasias da Mama/patologia , Feminino , Humanos , Transfecção
9.
Clin Cancer Res ; 22(11): 2650-8, 2016 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-26783290

RESUMO

PURPOSE: PI3K/AKT pathway activation is an important endocrine resistance mechanism in estrogen receptor-positive (ER(+)) breast cancer. After promising preclinical modeling of MK-2206, an allosteric pan-AKT inhibitor, with either estrogen deprivation or fulvestrant, we conducted a phase I trial in patients with metastatic ER(+)HER2(-) breast cancer to determine the recommended phase II treatment dose (RPTD) of MK-2206 when combined with either anastrozole, fulvestrant, or anastrozole/fulvestrant. EXPERIMENTAL DESIGN: ER(+) breast cancer cell lines were exposed in vitro to MK-2206 plus estrogen deprivation with or without fulvestrant and monitored for apoptosis. A standard 3+3 design was employed to first determine the maximum tolerated dose (MTD) of MK-2206 plus anastrozole based on cycle 1 toxicity. Each cycle was 28 days. The RPTD was determined on the basis of toxicities observed at MTD level during the first 3 cycles. Subsequent patients received MK-2206, at the RPTD determined above, plus fulvestrant or anastrozole/fulvestrant to define RPTD for these additional regimens. RESULTS: MK-2206 induced apoptosis in parental ER(+) but not in long-term estrogen-deprived cell lines, for which fulvestrant was required for apoptosis induction. Thirty-one patients enrolled. The RPTD was defined as MK-2206 150 mg orally weekly with prednisone prophylaxis for each combination. Grade 3 rash was dose limiting. 42% (95% CI, 23%-63%) patients derived clinical benefit without progression within 6 months. Response was not associated with tumor PIK3CA mutation. CONCLUSIONS: MK-2206 plus endocrine treatments were tolerable. MK-2206 in combination with anastrozole is being further evaluated in a phase II neoadjuvant trial for newly diagnosed ER(+)HER2(-) breast cancer. Clin Cancer Res; 22(11); 2650-8. ©2016 AACRSee related commentary by Jansen et al., p. 2599.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias da Mama/tratamento farmacológico , Adulto , Idoso , Anastrozol , Antineoplásicos Hormonais/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/toxicidade , Apoptose/efeitos dos fármacos , Biomarcadores Tumorais/metabolismo , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/secundário , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Sinergismo Farmacológico , Estradiol/administração & dosagem , Estradiol/análogos & derivados , Feminino , Fulvestranto , Compostos Heterocíclicos com 3 Anéis/administração & dosagem , Humanos , Hiperglicemia/induzido quimicamente , Hiperglicemia/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Dose Máxima Tolerável , Pessoa de Meia-Idade , Nitrilas/administração & dosagem , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Receptores de Estrogênio/metabolismo , Resultado do Tratamento , Triazóis/administração & dosagem
10.
Breast Cancer Res ; 7(5): 212-4, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16168140

RESUMO

Recent studies indicate that constitutive signaling through the phosphatidylinositol 3'-kinase (PI3K) pathway is a cause of treatment resistance in breast cancer patients. This implies that patients with tumors that exhibit aberrant PI3K signaling may benefit from targeted pathway inhibitors. The first agents to make it to the clinic are the rapamycin analogs. These compounds inhibit the downstream PI3K effector mTOR (mammalian target of rapamycin). A study presented in this issue of Breast Cancer Research suggests that recently developed inhibitors of phosphoinositide-dependent protein kinase 1, a more proximal target of the PI3K pathway, may provide an alternative route to effective PI3K pathway inhibition for breast cancer treatment.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Inibidores Enzimáticos/uso terapêutico , Inibidores de Fosfoinositídeo-3 Quinase , Antibióticos Antineoplásicos/uso terapêutico , Neoplasias da Mama/genética , Feminino , Amplificação de Genes/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Sirolimo/uso terapêutico
11.
Clin Cancer Res ; 21(22): 5121-5130, 2015 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-25991817

RESUMO

PURPOSE: Endocrine therapy, using tamoxifen or an aromatase inhibitor, remains first-line therapy for the management of estrogen receptor (ESR1)-positive breast cancer. However, ESR1 mutations or other ligand-independent ESR1 activation mechanisms limit the duration of response. The clinical efficacy of fulvestrant, a selective estrogen receptor downregulator (SERD) that competitively inhibits agonist binding to ESR1 and triggers receptor downregulation, has confirmed that ESR1 frequently remains engaged in endocrine therapy-resistant cancers. We evaluated the activity of a new class of selective estrogen receptor modulators (SERM)/SERD hybrids (SSH) that downregulate ESR1 in relevant models of endocrine-resistant breast cancer. Building on the observation that concurrent inhibition of ESR1 and the cyclin-dependent kinases 4 and 6 (CDK4/6) significantly increased progression-free survival in advanced patients, we explored the activity of different SERD- or SSH-CDK4/6 inhibitor combinations in models of endocrine therapy-resistant ESR1(+) breast cancer. EXPERIMENTAL DESIGN: SERDs, SSHs, and the CDK4/6 inhibitor palbociclib were evaluated as single agents or in combination in established cellular and animal models of endocrine therapy-resistant ESR1(+) breast cancer. RESULTS: The combination of palbociclib with a SERD or an SSH was shown to effectively inhibit the growth of MCF7 cell or ESR1-mutant patient-derived tumor xenografts. In tamoxifen-resistant MCF7 xenografts, the palbociclib/SERD or SSH combination resulted in an increased duration of response as compared with either drug alone. CONCLUSIONS: A SERD- or SSH-palbociclib combination has therapeutic potential in breast tumors resistant to endocrine therapies or those expressing ESR1 mutations. See related commentary by DeMichele and Chodosh, p. 4999.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Quinase 4 Dependente de Ciclina/genética , Quinase 6 Dependente de Ciclina/genética , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Receptor alfa de Estrogênio/genética , Moduladores Seletivos de Receptor Estrogênico/administração & dosagem , Animais , Antineoplásicos Hormonais/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Quinase 4 Dependente de Ciclina/antagonistas & inibidores , Quinase 6 Dependente de Ciclina/antagonistas & inibidores , Intervalo Livre de Doença , Resistencia a Medicamentos Antineoplásicos/genética , Estradiol/administração & dosagem , Estradiol/análogos & derivados , Feminino , Fulvestranto , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Células MCF-7 , Camundongos , Mutação , Piperazinas/administração & dosagem , Piridinas/administração & dosagem , Tamoxifeno/administração & dosagem , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Prog Brain Res ; 146: 111-26, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-14699960

RESUMO

Nerve growth factor (NGF) is required for the survival of developing sympathetic and sensory neurons. In the absence of NGF, these neurons undergo protein synthesis-dependent apoptosis. Ten years have gone by since the first reports of specific genes being upregulated during NGF deprivation-induced cell death. Over the last decade, a few additional genes (DP5, Bim, SM-20) have been added to a list that began with cyclin D1 and c-jun. In this chapter, we discuss the evidence that these genes act as regulators of neuronal cell death. We also suggest a hypothesis for how one gene, SM-20, may function to suppress a self-protection mechanism in NGF-deprived neurons.


Assuntos
Morte Celular/fisiologia , Proteínas de Ligação a DNA , Expressão Gênica/fisiologia , Fatores de Crescimento Neural/deficiência , Neurônios/citologia , Animais , Proteínas Reguladoras de Apoptose , Divisão Celular , Sobrevivência Celular/fisiologia , Células Cultivadas , Ciclina D1/genética , Ciclina D1/metabolismo , Quinases Ciclina-Dependentes/metabolismo , Dioxigenases , História do Século XX , História do Século XXI , Humanos , Hidroxilação , Prolina Dioxigenases do Fator Induzível por Hipóxia , Proteínas Imediatamente Precoces/genética , Proteínas Imediatamente Precoces/metabolismo , Imuno-Histoquímica , Fatores de Crescimento Neural/história , Fatores de Crescimento Neural/fisiologia , Neuropeptídeos/genética , Neuropeptídeos/metabolismo , Proteínas Nucleares/metabolismo , Fragmentos de Peptídeos/metabolismo , Pró-Colágeno-Prolina Dioxigenase/química , Pró-Colágeno-Prolina Dioxigenase/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-jun/genética , Proteínas Proto-Oncogênicas c-jun/metabolismo
14.
Cell Rep ; 4(6): 1116-30, 2013 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-24055055

RESUMO

To characterize patient-derived xenografts (PDXs) for functional studies, we made whole-genome comparisons with originating breast cancers representative of the major intrinsic subtypes. Structural and copy number aberrations were found to be retained with high fidelity. However, at the single-nucleotide level, variable numbers of PDX-specific somatic events were documented, although they were only rarely functionally significant. Variant allele frequencies were often preserved in the PDXs, demonstrating that clonal representation can be transplantable. Estrogen-receptor-positive PDXs were associated with ESR1 ligand-binding-domain mutations, gene amplification, or an ESR1/YAP1 translocation. These events produced different endocrine-therapy-response phenotypes in human, cell line, and PDX endocrine-response studies. Hence, deeply sequenced PDX models are an important resource for the search for genome-forward treatment options and capture endocrine-drug-resistance etiologies that are not observed in standard cell lines. The originating tumor genome provides a benchmark for assessing genetic drift and clonal representation after transplantation.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Receptor alfa de Estrogênio/genética , Proteínas Adaptadoras de Transdução de Sinal/genética , Alelos , Animais , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Resistencia a Medicamentos Antineoplásicos , Estradiol/farmacologia , Feminino , Amplificação de Genes , Instabilidade Genômica , Xenoenxertos , Humanos , Camundongos , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , Estadiamento de Neoplasias , Fosfoproteínas/genética , Mutação Puntual , RNA Neoplásico/biossíntese , RNA Neoplásico/genética , Fatores de Transcrição , Translocação Genética , Proteínas de Sinalização YAP
15.
Steroids ; 76(8): 750-2, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21420991

RESUMO

Endocrine therapy has been the most effective treatment modality for hormone receptor positive breast cancer. However, its efficacy has been limited by either de novo or acquired resistance. Recent data indicates that activation of the phosphatidylinositol 3-kinase (PI3K) signaling is associated with the poor outcome luminal B subtype of breast cancer and accompanied by the development of endocrine therapy resistance. Importantly, inhibition of PI3K pathway signaling in endocrine resistant breast cancer cell lines reduces cell survival and improves treatment response to endocrine agents. Interestingly, mutations in PIK3CA, the alpha catalytic subunit of the class IA PI3K, which renders cells dependent on PI3K pathway signaling, is the most common genetic abnormality identified in hormone receptor positive breast cancer. The synthetic lethality observed between estrogen deprivation and PI3K pathway inhibition in estrogen receptor positive (ER+) breast cancer cell lines provides further scientific rational to target both estrogen receptor and the PI3K pathway in order to improve the outcome of ER+ breast cancer.


Assuntos
Antineoplásicos Hormonais/uso terapêutico , Inibidores da Aromatase/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos , Receptor alfa de Estrogênio/genética , Neoplasias Hormônio-Dependentes/tratamento farmacológico , Fosfatidilinositol 3-Quinases/metabolismo , Neoplasias da Mama/enzimologia , Estrogênios/metabolismo , Feminino , Humanos , Mutação , Neoplasias Hormônio-Dependentes/enzimologia , Fosfatidilinositol 3-Quinases/genética , Transdução de Sinais
16.
Cancer Discov ; 1(4): 287-8, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22096658

RESUMO

Endocrine therapy-resistant estrogen receptor-positive (ER(+)) breast cancer is the most common cause of breast cancer death. Miller and colleagues demonstrate that ligand-independent ER activity promotes the growth of breast cancer cells through CDK4/E2F. As an independent event, the phosphatidylinositol 3-kinase (PI3K) pathway is also upregulated in endocrine therapy-resistant cells. Promising preclinical evidence by several groups for the combination of an inhibitor of ligand-independent ER, fulvestrant, with PI3K inhibition, has led to the activation of trials evaluating this concept.


Assuntos
Neoplasias da Mama/genética , Fatores de Transcrição E2F/genética , Fatores de Transcrição E2F/metabolismo , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Estrogênios/deficiência , Animais , Feminino , Humanos
17.
J Clin Oncol ; 28(7): 1161-7, 2010 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-20124184

RESUMO

PURPOSE To determine whether plasma estradiol (E2) levels are related to gene expression in estrogen receptor (ER)-positive breast cancers in postmenopausal women. Materials and METHODS Genome-wide RNA profiles were obtained from pretreatment core-cut tumor biopsies from 104 postmenopausal patients with primary ER-positive breast cancer treated with neoadjuvant anastrozole. Pretreatment plasma E2 levels were determined by highly sensitive radioimmunoassay. Genes were identified for which expression was correlated with pretreatment plasma E2 levels. Validation was performed in an independent set of 73 ER-positive breast cancers. Results The expression of many known estrogen-responsive genes and gene sets was highly significantly associated with plasma E2 levels (eg, TFF1/pS2, GREB1, PDZK1 and PGR; P < .005). Plasma E2 explained 27% of the average expression of these four average estrogen-responsive genes (ie, AvERG; r = 0.51; P < .0001), and a standardized mean of plasma E2 levels and ER transcript levels explained 37% (r, 0.61). These observations were validated in an independent set of 73 ER-positive tumors. Exploratory analysis suggested that addition of the nuclear coregulators in a multivariable analysis with ER and E2 levels might additionally improve the relationship with the AvERG. Plasma E2 and the standardized mean of E2 and ER were both significantly correlated with 2-week Ki67, a surrogate marker of clinical outcome (r = -0.179; P = .05; and r = -0.389; P = .0005, respectively). CONCLUSION Plasma E2 levels are significantly associated with gene expression of ER-positive breast cancers and should be considered in future genomic studies of ER-positive breast cancer. The AvERG is a new experimental tool for the study of putative estrogenic stimuli of breast cancer.


Assuntos
Neoplasias da Mama/metabolismo , Estradiol/sangue , Estrogênios/farmacologia , Perfilação da Expressão Gênica , Receptores de Estrogênio/análise , Idoso , Anastrozol , Neoplasias da Mama/sangue , Neoplasias da Mama/química , Feminino , Humanos , Antígeno Ki-67/análise , Pessoa de Meia-Idade , Nitrilas/uso terapêutico , Pós-Menopausa , Triazóis/uso terapêutico
18.
Cancer Res ; 69(9): 3955-62, 2009 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-19366795

RESUMO

Several phosphoinositide 3-kinase (PI3K) catalytic subunit inhibitors are currently in clinical trial. We therefore sought to examine relationships between pharmacologic inhibition and somatic mutations in PI3K catalytic subunits in estrogen receptor (ER)-positive breast cancer, in which these mutations are particularly common. RNA interference (RNAi) was used to determine the effect of selective inhibition of PI3K catalytic subunits, p110alpha and p110beta, in ER(+) breast cancer cells harboring either mutation (PIK3CA) or gene amplification (PIK3CB). p110alpha RNAi inhibited growth and promoted apoptosis in all tested ER(+) breast cancer cells under estrogen deprived-conditions, whereas p110beta RNAi only affected cells harboring PIK3CB amplification. Moreover, dual p110alpha/p110beta inhibition potentiated these effects. In addition, treatment with the clinical-grade PI3K catalytic subunit inhibitor BEZ235 also promoted apoptosis in ER(+) breast cancer cells. Importantly, estradiol suppressed apoptosis induced by both gene knockdowns and BEZ235 treatment. Our results suggest that PI3K inhibitors should target both p110alpha and p110beta catalytic subunits, whether wild-type or mutant, and be combined with endocrine therapy for maximal efficacy when treating ER(+) breast cancer.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/enzimologia , Estradiol/farmacologia , Inibidores de Fosfoinositídeo-3 Quinase , Inibidores de Proteínas Quinases/farmacologia , Apoptose/genética , Neoplasias da Mama/genética , Processos de Crescimento Celular/genética , Classe I de Fosfatidilinositol 3-Quinases , Amplificação de Genes , Humanos , Imidazóis/farmacologia , Hibridização in Situ Fluorescente , Fosfatidilinositol 3-Quinases/biossíntese , Fosfatidilinositol 3-Quinases/genética , Quinolinas/farmacologia , Interferência de RNA , RNA Interferente Pequeno/genética , Receptores de Estrogênio/biossíntese , Transfecção
19.
J Morphol ; 221(3): 321-341, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29865409

RESUMO

Transmission electron microscopy reveals that the somatic testicular tissues and sperm ducts are elaborations of the epithelial lining of the tail coelom. The testes consist of closely packed spermatogonia embedded between specialized lateral field cells. These cells contain few organelles and appear to function mainly as a compartment boundary. Masses of spermatogenic cells are released into the tail coelom from the anterior end of the testes. The sperm ducts, lined by simple cuboidal ciliated epithelium, collect mature spermatozoa from the tail coelom and convey them to the blindly ending seminal vesicles. The sperm ducts also modify coelomic fluid entering them along with the spermatozoa. The seminal vesicles consist of a simple glandular lining epithelium embedded in the stratified epidermis. Secretions of the lining epithelium surround the enclosed sperm mass and correspond in position to a noncellular spermatophore coat visible by light microscopy around released sperm masses. Spermatophores leave the seminal vesicles through a temporary split that forms between microfilament-containing suture cells. Maturation of spermatozoa and filling of the seminal vesicles is cyclical, occurring late each day. © 1994 Wiley-Liss, Inc.

20.
J Biol Chem ; 279(40): 42072-81, 2004 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-15286081

RESUMO

Activation of Ret, the receptor-tyrosine kinase for the glial cell line-derived neurotrophic factor (GDNF) family ligands (GFLs), results in the recruitment and assembly of adaptor protein complexes that function to transduce signals downstream of the receptor. Here we identify Dok-6, a novel member of the Dok-4/5 subclass of the p62 Dok family of intracellular adaptor molecules, and characterize its interaction with Ret. Expression analysis reveals that Dok-6 is highly expressed in the developing central nervous system and is co-expressed with Ret in several locations, including sympathetic, sensory, and parasympathetic ganglia, as well as in the ureteric buds of the developing kidneys. Pull-down assays using the Dok-6 phosphotyrosine binding (PTB) domain and GDNF-activated Ret indicate that Dok-6 binds to the phosphorylated Ret Tyr(1062) residue. Moreover, ligand activation of Ret resulted in phosphorylation of tyrosine residue(s) located within the unique C terminus of Dok-6 predominantly through a Src-dependent mechanism, indicating that Dok-6 is a substrate of the Ret-Src signaling pathway. Interestingly, expression of Dok-6 potentiated GDNF-induced neurite outgrowth in GDNF family receptor alpha1 (GFRalpha1)-expressing Neuro2A cells that was dependent upon the C-terminal residues of Dok-6. Taken together, these data identify Dok-6 as a novel Dok-4/5-related adaptor molecule that may function in vivo to transduce signals that regulate Ret-mediated processes such as axonal projection.


Assuntos
Proteínas Adaptadoras de Transporte Vesicular/fisiologia , Neuritos/ultraestrutura , Proteínas Oncogênicas/fisiologia , Receptores Proteína Tirosina Quinases/fisiologia , Proteínas Adaptadoras de Transdução de Sinal , Animais , Sequência de Bases , Sítios de Ligação , Linhagem Celular Tumoral , Embrião de Mamíferos , Humanos , Camundongos , Dados de Sequência Molecular , Ligação Proteica , Proteínas Proto-Oncogênicas c-ret , Alinhamento de Sequência , Transdução de Sinais , Distribuição Tecidual , Transfecção
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