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1.
J Mol Cell Cardiol ; 127: 125-133, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30550751

RESUMO

Huntington's disease (HD) is a fatal hereditary neurodegenerative disorder, best known for its clinical triad of progressive motor impairment, cognitive deficits and psychiatric disturbances, is caused by CAG-repeat expansion in exon 1 of Huntingtin (HTT). However, in addition to the neurological disease, mutant HTT (mHTT), which is ubiquitously expressed in all tissues, impairs other organ systems. Not surprisingly, cardiovascular dysautonomia as well as the deterioration of circadian rhythms are among the earliest detectable pathophysiological changes in individuals with HD. Mitochondrial dysfunction in the brain and skeletal muscle in HD has been well documented, as the disease progresses. However, not much is known about mitochondrial abnormalities in the heart. In this study, we describe a role for Drp1/Fis1-mediated excessive mitochondrial fission and dysfunction, associated with lysosomal dysfunction in H9C2 expressing long polyglutamine repeat (Q73) and in human iPSC-derived cardiomyocytes transfected with Q77. Expression of long polyglutamine repeat led to reduced ATP production and mitochondrial fragmentation. We observed an increased accumulation of damaged mitochondria in the lysosome that was coupled with lysosomal dysfunction. Importantly, reducing Drp1/Fis1-mediated mitochondrial damage significantly improved mitochondrial function and cell survival. Finally, reducing Fis1-mediated Drp1 recruitment to the mitochondria, using the selective inhibitor of this interaction, P110, improved mitochondrial structure in the cardiac tissue of R6/2 mice. We suggest that drugs focusing on the central nervous system will not address mitochondrial function across all organs, and therefore will not be a sufficient strategy to treat or slow down HD disease progression.


Assuntos
Dinaminas/metabolismo , Doença de Huntington/metabolismo , Doença de Huntington/patologia , Lisossomos/metabolismo , Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo , Animais , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Linhagem Celular , Modelos Animais de Doenças , Metabolismo Energético , GTP Fosfo-Hidrolases/farmacologia , Humanos , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Células-Tronco Pluripotentes Induzidas/metabolismo , Lisossomos/ultraestrutura , Camundongos Transgênicos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/ultraestrutura , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Fragmentos de Peptídeos/farmacologia , Peptídeos/metabolismo , Expansão das Repetições de Trinucleotídeos
2.
Breast Cancer Res Treat ; 174(2): 401-412, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30560461

RESUMO

PURPOSE: Estrogen receptor-alpha (ER) is a therapeutic target of ER-positive (ER+) breast cancers. Although ER signaling is complex, many mediators of this pathway have been identified. Specifically, phosphorylation of ER at serine 118 affects responses to estrogen and therapeutic ligands and has been correlated with clinical outcomes in ER+ breast cancer patients. We hypothesized that a newly described germline variant (S118P) at this residue would drive cellular changes consistent with breast cancer development and/or hormone resistance. METHODS: Isogenic human breast epithelial cell line models harboring ER S118P were developed via genome editing and characterized to determine the functional effects of this variant. We also examined the frequency of ER S118P in a case-control study (N = 536) of women with and without breast cancer with a familial risk. RESULTS: In heterozygous knock-in models, the S118P variant demonstrated no significant change in proliferation, migration, MAP Kinase pathway signaling, or response to the endocrine therapies tamoxifen and fulvestrant. Further, there was no difference in the prevalence of S118P between women with and without cancer relative to population registry databases. CONCLUSIONS: This study suggests that the ER S118P variant does not affect risk for breast cancer or hormone therapy resistance. Germline screening and modification of treatments for patients harboring this variant are likely not warranted.


Assuntos
Antineoplásicos Hormonais/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/epidemiologia , Receptor alfa de Estrogênio/genética , Mutação em Linhagem Germinativa , Adulto , Idoso , Neoplasias da Mama/genética , Estudos de Casos e Controles , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Receptor alfa de Estrogênio/metabolismo , Feminino , Fulvestranto/uso terapêutico , Variação Genética , Humanos , Incidência , Células MCF-7 , Pessoa de Meia-Idade , Fosforilação , Análise de Sobrevida , Tamoxifeno/uso terapêutico , Resultado do Tratamento
3.
AIDS Behav ; 22(6): 1835-1848, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28361452

RESUMO

Incarcerated populations have relatively high HIV prevalence but little has been reported about their aggregate HIV risk behaviors or perceptions of risk. A random selection of HIV-negative men (n = 855) entering a US state prison system were surveyed to assess five risk behaviors and his self-perceived HIV risk. Using multivariate logistic regression, we identified factors associated with having elevated actual but low perceived risk (EALPR). Of the 826 men with complete data, 88% were at elevated risk. While 64% of the sample had risk perceptions concordant with their actual risk, 14% had EALPR (with the remainder at low actual but high perceived risk). EALPR rates were lower in those with a pre-incarceration HIV test but higher for those with a negative prison entry HIV test. HIV testing counseling should assess for discordance between actual and perceived risk and communicate the continued risk of HIV despite a negative result.


Assuntos
Infecções por HIV/psicologia , Conhecimentos, Atitudes e Prática em Saúde , Prisioneiros/psicologia , Prisões , Assunção de Riscos , Adolescente , Adulto , Aconselhamento , Infecções por HIV/epidemiologia , Inquéritos Epidemiológicos , Humanos , Masculino , Motivação , Percepção , Prevalência , Risco , Inquéritos e Questionários
4.
Proc Natl Acad Sci U S A ; 112(37): 11583-8, 2015 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-26324937

RESUMO

The tumor protein 53 (TP53) tumor suppressor gene is the most frequently somatically altered gene in human cancers. Here we show expression of N-Myc down-regulated gene 1 (NDRG1) is induced by p53 during physiologic low proliferative states, and mediates centrosome homeostasis, thus maintaining genome stability. When placed in physiologic low-proliferating conditions, human TP53 null cells fail to increase expression of NDRG1 compared with isogenic wild-type controls and TP53 R248W knockin cells. Overexpression and RNA interference studies demonstrate that NDRG1 regulates centrosome number and amplification. Mechanistically, NDRG1 physically associates with γ-tubulin, a key component of the centrosome, with reduced association in p53 null cells. Strikingly, TP53 homozygous loss was mutually exclusive of NDRG1 overexpression in over 96% of human cancers, supporting the broad applicability of these results. Our study elucidates a mechanism of how TP53 loss leads to abnormal centrosome numbers and genomic instability mediated by NDRG1.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Centrossomo/ultraestrutura , Regulação Neoplásica da Expressão Gênica , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Aneuploidia , Animais , Mama/metabolismo , Linhagem Celular , Proliferação de Células , Centrossomo/metabolismo , Feminino , Genoma , Heterozigoto , Homeostase , Homozigoto , Humanos , Hibridização in Situ Fluorescente , Camundongos , Camundongos Knockout , Neoplasias/patologia , Fenótipo , Interferência de RNA , Tubulina (Proteína)/metabolismo
5.
Proc Natl Acad Sci U S A ; 112(45): E6205-14, 2015 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-26508629

RESUMO

Recurrent human epidermal growth factor receptor 2 (HER2) missense mutations have been reported in human cancers. These mutations occur primarily in the absence of HER2 gene amplification such that most HER2-mutant tumors are classified as "negative" by FISH or immunohistochemistry assays. It remains unclear whether nonamplified HER2 missense mutations are oncogenic and whether they are targets for HER2-directed therapies that are currently approved for the treatment of HER2 gene-amplified breast cancers. Here we functionally characterize HER2 kinase and extracellular domain mutations through gene editing of the endogenous loci in HER2 nonamplified human breast epithelial cells. In in vitro and in vivo assays, the majority of HER2 missense mutations do not impart detectable oncogenic changes. However, the HER2 V777L mutation increased biochemical pathway activation and, in the context of a PIK3CA mutation, enhanced migratory features in vitro. However, the V777L mutation did not alter in vivo tumorigenicity or sensitivity to HER2-directed therapies in proliferation assays. Our results suggest the oncogenicity and potential targeting of HER2 missense mutations should be considered in the context of cooperating genetic alterations and provide previously unidentified insights into functional analysis of HER2 mutations and strategies to target them.


Assuntos
Movimento Celular/genética , Mutação de Sentido Incorreto/genética , Neoplasias/genética , Receptor ErbB-2/genética , Transdução de Sinais/genética , Western Blotting , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Ensaio de Unidades Formadoras de Colônias , Citometria de Fluxo , Marcação de Genes , Células HEK293 , Humanos , Immunoblotting , Lapatinib , Quinazolinas , Quinolinas , Tiazóis
6.
Breast Cancer Res Treat ; 162(3): 451-464, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28190247

RESUMO

BACKGROUND/PURPOSE: The combined contributions of oncogenes and tumor suppressor genes toward carcinogenesis remain poorly understood. Elucidation of cancer gene cooperativity can provide new insights leading to more effective use of therapies. EXPERIMENTAL DESIGN/METHODS: We used somatic cell genome editing to introduce singly and in combination PIK3CA mutations (E545K or H1047R) with TP53 alterations (R248W or knockout), to assess any enhanced cancerous phenotypes. The non-tumorigenic human breast epithelial cell line, MCF10A, was used as the parental cell line, and resultant cells were assessed via various in vitro assays, growth as xenografts, and drug sensitivity assays using targeted agents and chemotherapies. RESULTS: Compared to single-gene-targeted cells and parental controls, cells with both a PIK3CA mutation and TP53 alteration had increased cancerous phenotypes including cell proliferation, soft agar colony formation, aberrant morphology in acinar formation assays, and genomic heterogeneity. Cells also displayed varying sensitivities to anti-neoplastic drugs, although all cells with PIK3CA mutations showed a relative increased sensitivity to paclitaxel. All cell lines remained non-tumorigenic. CONCLUSIONS: This cell line panel provides a resource for further elucidating cooperative genetic mediators of carcinogenesis and response to therapies.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Classe I de Fosfatidilinositol 3-Quinases/genética , Mutação , Fenótipo , Proteína Supressora de Tumor p53/genética , Animais , Ciclo Celular , Linhagem Celular Tumoral , Proliferação de Células , Centrômero/genética , Variações do Número de Cópias de DNA , Modelos Animais de Doenças , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Amplificação de Genes , Edição de Genes , Técnicas de Inativação de Genes , Instabilidade Genômica , Genótipo , Humanos , Camundongos , Paclitaxel/farmacologia
7.
Proc Natl Acad Sci U S A ; 111(49): 17606-11, 2014 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-25422431

RESUMO

Tamoxifen is effective for treating estrogen receptor-alpha (ER) positive breast cancers. However, few molecular mediators of tamoxifen resistance have been elucidated. Here we describe a previously unidentified gene, MACROD2 that confers tamoxifen resistance and estrogen independent growth. We found MACROD2 is amplified and overexpressed in metastatic tamoxifen-resistant tumors. Transgene overexpression of MACROD2 in breast cancer cell lines results in tamoxifen resistance, whereas RNAi-mediated gene knock down reverses this phenotype. MACROD2 overexpression also leads to estrogen independent growth in xenograft assays. Mechanistically, MACROD2 increases p300 binding to estrogen response elements in a subset of ER regulated genes. Primary breast cancers and matched metastases demonstrate MACROD2 expression can change with disease evolution, and increased expression and amplification of MACROD2 in primary tumors is associated with worse overall survival. These studies establish MACROD2 as a key mediator of estrogen independent growth and tamoxifen resistance, as well as a potential novel target for diagnostics and therapy.


Assuntos
Neoplasias da Mama/metabolismo , Enzimas Reparadoras do DNA/metabolismo , Resistencia a Medicamentos Antineoplásicos , Estrogênios/metabolismo , Hidrolases/metabolismo , Tamoxifeno/farmacologia , Sequência de Bases , Linhagem Celular Tumoral , Proliferação de Células , Epigênese Genética , Feminino , Deleção de Genes , Dosagem de Genes , Humanos , Dados de Sequência Molecular , Transplante de Neoplasias , Fenótipo , Prognóstico , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Receptores de Estrogênio/metabolismo , Transgenes , Resultado do Tratamento
8.
Prostate ; 76(8): 703-14, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26835873

RESUMO

BACKGROUND: There is an urgent need to develop new agents for treating metastatic prostate cancer to overcome multiple drug resistance to the current standard targeted cancer therapy. Emetine is a highly cytotoxic natural product protein synthesis inhibitor, which is toxic to all cell types. Its cytotoxicity can be blocked by derivatizing its N-2' position. Thus emetine can be selectively delivered to cancer cells in the region of metastatic cancer as a prodrug that will be activated by an enzyme selectively overexpressed within the metastatic tumor microenvironment. In this work, we convert emetine to a prodrug activatable by the fibroblast activation protein (FAP), a serine protease overexpressed by the carcinoma associated fibroblasts. METHOD: By using an iterative structure-activity relationship strategy, several peptidyl emetine prodrug analogs (1-11) were synthesized by chemical derivatization of emetine at its N-2' position and tested for in-vitro activation by FAP. The lead prodrug 11 is made up of a DPPIV activatable prodrug precursor 10 (Ala-Pro-PABC-Emetine) coupled to FAP substrate (Ala-Ser-Gly-Pro-Ala-Gly-Pro). Activation assays of the prodrugs were performed in purified FAP, DPPIV, FBS, and human serum and were analyzed by LCMS. In vitro cytotoxicity assays of these prodrugs are carried out in prostate (LNCaP, PC3) and breast (MCF7 and MDA-MB-231) cancer cell lines. The prodrugs are also tested in normal immortalized human prostatic epithelial cell line (PrEC). RESULTS: The lead FAP activated emetine prodrug 11 is activated to emetine in tandem by FAP and DPPIV in about 70% conversion within 24 hr. In prostate and breast cancer cell lines treated with prodrug 11, it is found to be equipotent with emetine in the presence of FAP and DPPIV. However, in the PrEC cell line grown in serum free media, prodrug 11 is more than 200-fold less cytotoxic than emetine in the absence of FAP and DPPIV. CONCLUSION: This FAP activated prodrug of cytotoxic agent emetine further shows the crucial role of the N-2' position of emetine in controlling its cytotoxicity. Significantly reduced toxicity observed in the PrEC cell line in the absence of FAP and DPPIV shows that prodrug 11 could be systemically delivered to regions of metastatic prostate cancer or other solid tumor for activation by cancer selective enzymes within the cancer microenvironment, such as FAP that is overexpressed by the carcinoma-associated fibroblasts. The two-step tandem enzymatic activation of prodrug 11 by FAP and DPPIV is a strategy for overcoming steric hindrance.


Assuntos
Antineoplásicos/uso terapêutico , Dipeptidil Peptidase 4/metabolismo , Desenho de Fármacos , Emetina/uso terapêutico , Gelatinases/metabolismo , Proteínas de Membrana/metabolismo , Pró-Fármacos/uso terapêutico , Neoplasias da Próstata/tratamento farmacológico , Serina Endopeptidases/metabolismo , Linhagem Celular Tumoral , Endopeptidases , Humanos , Masculino , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Relação Estrutura-Atividade
9.
Prostate ; 76(13): 1218-26, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27338150

RESUMO

BACKGROUND: We have previously documented a paradoxical anti-tumor effect when castration-resistant prostate cancer patients were treated with intermittent, high-dose testosterone (i.e., Bipolar Androgen Therapy; BAT). Because, an adaptive increase in androgen receptor expression following chronic androgen deprivation therapy (ADT) may underlie this effect, we tested whether men with hormone-sensitive (HS) prostate cancer (PC) would also respond to BAT if given following a 6-month ADT lead-in. METHODS: Asymptomatic HS PC patients with low metastatic burden or non-metastatic biochemically recurrent disease were enrolled. Following 6-month of ADT, those with a PSA <4 ng/ml went on to receive alternating 3-month cycles of BAT and ADT. BAT was administered as intramuscular testosterone (T) cypionate or enanthate 400 mg on Days (D) 1, 29, and 57. ADT was continued throughout the study to allow rapid cycling from near castrate to supraphysiologic range T following T injections. The primary endpoint was the percent of patients with a PSA <4 ng/ml after 18 months. Secondary endpoints included radiographic response and quality of life (QoL). RESULTS: Twenty-nine of 33 patients received BAT following the ADT lead-in. The primary endpoint was met, with 17/29 men (59%, 90% confidence interval: 42-74%) having a PSA <4 ng/ml at 18 months. Ten patients receiving BAT had RECIST evaluable disease, and eight (80%) objective responses were observed (four complete; four partial). Three patients progressed per RECIST criteria and three had unconfirmed progression on bone scan. Men treated with 6-month of ADT had improved QoL following the first cycle of BAT as measured by the SF-36, FACT-P, and IIEF surveys. CONCLUSIONS: BAT demonstrated preliminary efficacy in men with HS PC following 6-month of ADT. BAT may improve QoL in men treated with ADT. Prostate 76:1218-1226, 2016. © 2016 Wiley Periodicals, Inc.


Assuntos
Antagonistas de Androgênios/uso terapêutico , Neoplasias de Próstata Resistentes à Castração/diagnóstico , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Testosterona/uso terapêutico , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/sangue , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/sangue , Qualidade de Vida
10.
Colorectal Dis ; 18(5): 488-95, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26382283

RESUMO

AIM: The treatment of transsphincteric anal fistula requires a balance between eradication of the disease and preservation of faecal control. A cutting seton is an old tool that is now out of vogue for many surgeons. We hypothesized that the concept remains reliable and safe with results that exceed those reported for many of the more recently described methods. METHOD: A retrospective review was conducted of real-time electronic health records (single institution, single surgeon) of patients presenting during the 14 years between 2001 and 2014 with a transsphincteric anal fistula who were treated with a cutting seton. Excluded were patients with Crohn's disease, fistulae related to malignancy or a previous anastomosis and patients whose fistula was treated by another method including a loose draining seton. Data collection included demographics, duration of the disease, duration of the treatment, outcome and continence. RESULTS: In all, 121 patients (80 men) of mean age 40.2 ± 12.2 years (range 18-76) with a mean follow-up of 5.1 ± 3.3 (1-24) months were included in the analysis. The median duration of symptoms was 6 (1-84) months; 36% had failed other fistula surgery, 12% had a complex fistula with more than one track and 35% had some form of comorbidity. The median time to healing was 3 (1-18) months; 7.4% required further surgery, but eventually 98% had complete fistula healing. The incontinence rate decreased postoperatively to 11.6% from 19% before treatment with 17/121 with pre-existing incontinence resolved and 8/107 new cases developing. CONCLUSION: Despite its retrospective non-comparative design, the study has demonstrated that a cutting seton is a safe, well tolerated and highly successful treatment for transsphincteric anal fistula and is followed overall by improved continence. The results compare very favourably with other techniques.


Assuntos
Canal Anal/cirurgia , Procedimentos Cirúrgicos do Sistema Digestório/instrumentação , Fístula Retal/cirurgia , Adolescente , Adulto , Idoso , Procedimentos Cirúrgicos do Sistema Digestório/métodos , Incontinência Fecal/etiologia , Incontinência Fecal/cirurgia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Fístula Retal/complicações , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
11.
Prostate ; 74(13): 1308-19, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25053236

RESUMO

BACKGROUND: As carcinoma progresses, the stroma undergoes a variety of phenotypic changes, including the presence of carcinoma-associated fibroblasts (CAFs) that express fibroblast activation protein (FAP). FAP is a post-prolyl endopeptidase whose expression in a healthy adult is largely restricted to the cancer-associated stroma. FAP-targeted prodrugs with a 100-fold greater therapeutic window over the parent compound were previously generated. METHODS: Prodrugs and non-cleavable controls were incubated in the presence of FAP. Plasma and tumor half-lives (t1/2) of the full-length and active forms of the prodrugs were determined using LCMS. Biodistribution studies of prodrug activation were performed. Histopathological analysis of tissues from treated animals were compared to vehicle-treated controls. Toxicity and efficacy studies were performed in human breast (MDA-MB-231 and MCF-7) and prostate (LNCaP) cancer xenografts models. RESULTS: These FAP-activated prodrugs have a significantly slower clearance from tumor tissue than the circulation (∼12 vs. ∼4.5 hr). Micromolar concentrations of active drug persist in the tumor. Active drug is detected in non-target tissues; however, histopathologic evaluation reveals no evidence of drug-induced toxicity. A FAP-activated prodrug (ERGETGP-S12ADT) inhibits tumor growth in multiple human breast and prostate cancer xenograft models. The anti-tumor effect is comparable to that observed with docetaxel, but results in significantly less toxicity. CONCLUSION: FAP-activated prodrugs are a viable strategy for the management of prostate and other cancers. These prodrugs exhibit less toxicity than a commonly used chemotherapeutic agent. Further refinement of the FAP cleavage site for greater specificity may reduce prodrug activation in non-target tissues and enhance clinical benefit.


Assuntos
Adenocarcinoma/tratamento farmacológico , Antineoplásicos/farmacocinética , Gelatinases/farmacocinética , Proteínas de Membrana/farmacocinética , Pró-Fármacos/farmacocinética , Neoplasias da Próstata/tratamento farmacológico , Serina Endopeptidases/farmacocinética , Adenocarcinoma/patologia , Animais , Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , Endopeptidases , Gelatinases/efeitos adversos , Gelatinases/uso terapêutico , Humanos , Masculino , Proteínas de Membrana/efeitos adversos , Proteínas de Membrana/uso terapêutico , Camundongos , Pró-Fármacos/efeitos adversos , Pró-Fármacos/uso terapêutico , Neoplasias da Próstata/patologia , Serina Endopeptidases/efeitos adversos , Serina Endopeptidases/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto
12.
bioRxiv ; 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38328141

RESUMO

Lysine-specific demethylase 1 (LSD1 or KDM1A ) has emerged as a critical mediator of tumor progression in metastatic castration-resistant prostate cancer (mCRPC). Among mCRPC subtypes, neuroendocrine prostate cancer (NEPC) is an exceptionally aggressive variant driven by lineage plasticity, an adaptive resistance mechanism to androgen receptor axis-targeted therapies. Our study shows that LSD1 expression is elevated in NEPC and associated with unfavorable clinical outcomes. Using genetic approaches, we validated the on-target effects of LSD1 inhibition across various models. We investigated the therapeutic potential of bomedemstat, an orally bioavailable, irreversible LSD1 inhibitor with low nanomolar potency. Our findings demonstrate potent antitumor activity against CRPC models, including tumor regressions in NEPC patient-derived xenografts. Mechanistically, our study uncovers that LSD1 inhibition suppresses the neuronal transcriptional program by downregulating ASCL1 through disrupting LSD1:INSM1 interactions and de-repressing YAP1 silencing. Our data support the clinical development of LSD1 inhibitors for treating CRPC - especially the aggressive NE phenotype. Statement of Significance: Neuroendocrine prostate cancer presents a clinical challenge due to the lack of effective treatments. Our research demonstrates that bomedemstat, a potent and selective LSD1 inhibitor, effectively combats neuroendocrine prostate cancer by downregulating the ASCL1- dependent NE transcriptional program and re-expressing YAP1.

13.
Proc Natl Acad Sci U S A ; 106(8): 2835-40, 2009 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-19196980

RESUMO

The phosphatidylinositol 3-kinase subunit PIK3CA is frequently mutated in human cancers. Here we used gene targeting to "knock in" PIK3CA mutations into human breast epithelial cells to identify new therapeutic targets associated with oncogenic PIK3CA. Mutant PIK3CA knockin cells were capable of epidermal growth factor and mTOR-independent cell proliferation that was associated with AKT, ERK, and GSK3beta phosphorylation. Paradoxically, the GSK3beta inhibitors lithium chloride and SB216763 selectively decreased the proliferation of human breast and colorectal cancer cell lines with oncogenic PIK3CA mutations and led to a decrease in the GSK3beta target gene CYCLIN D1. Oral treatment with lithium preferentially inhibited the growth of nude mouse xenografts of HCT-116 colon cancer cells with mutant PIK3CA compared with isogenic HCT-116 knockout cells containing only wild-type PIK3CA. Our findings suggest GSK3beta is an important effector of mutant PIK3CA, and that lithium, an FDA-approved therapy for bipolar disorders, has selective antineoplastic properties against cancers that harbor these mutations.


Assuntos
Mutação , Oncogenes , Fosfatidilinositol 3-Quinases/genética , Animais , Neoplasias da Mama/enzimologia , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Classe I de Fosfatidilinositol 3-Quinases , Neoplasias Colorretais/enzimologia , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Técnicas de Introdução de Genes , Quinase 3 da Glicogênio Sintase/metabolismo , Glicogênio Sintase Quinase 3 beta , Humanos , Glândulas Mamárias Humanas/metabolismo , Camundongos , Camundongos Nus , Fosforilação , Proteínas Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serina-Treonina Quinases TOR , Transplante Heterólogo
14.
Folia Med (Plovdiv) ; 64(3): 380-387, 2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35856097

RESUMO

Despite being a physiological condition, human pregnancy is known to cause numerous complications that can endanger the life of the mother and the fetus alike. While the majority of complications are mostly limited within the peripartum period, more and more information is available about persistently higher short- and long-term cardiovascular risk after a pregnancy complicated by a hypertensive disorder. There is evidence that women after gestational hypertension or preeclampsia are more likely to develop arterial hypertension, coronary atherosclerosis, myocardial infarction, stroke, peripheral artery disease, and even diabetes mellitus and venous thromboembolism years after the target pregnancy. This has urged some authors to view hypertensive disorders of pregnancy as a "stress test" for the maternal organism that unmasks latent endothelial dysfunction. An explanation is sought in the presence of common risk factors and underlying pathological pathways with cardiovascular diseases, although a certain etiological mechanism for the development of hypertensive disorders in pregnancy has not been established yet. More attention is needed towards the follow-up of women after a hypertensive pregnancy as it could be an opportunity for early prevention of cardiovascular diseases.


Assuntos
Doenças Cardiovasculares , Hipertensão Induzida pela Gravidez , Hipertensão , Pré-Eclâmpsia , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Feminino , Humanos , Hipertensão/epidemiologia , Hipertensão Induzida pela Gravidez/epidemiologia , Pré-Eclâmpsia/epidemiologia , Gravidez , Fatores de Risco
15.
Oncotarget ; 13: 373-386, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35186194

RESUMO

Activating variants in the PEST region of NOTCH1 have been associated with aggressive phenotypes in human cancers, including triple-negative breast cancer (TNBC). Previous studies suggested that PEST domain variants in TNBC patients resulted in increased cell proliferation, invasiveness, and decreased overall survival. In this study, we assess the phenotypic transformation of activating NOTCH1 variants and their response to standard of care therapies. AAV-mediated gene targeting was used to isogenically incorporate 3 NOTCH1 variants, including a novel TNBC frameshift variant, in two non-tumorigenic breast epithelial cell lines, MCF10A and hTERT-IMEC. Two different variants at the NOTCH1 A2241 site (A2441fs and A2441T) both demonstrated increased transformative properties when compared to a non-transformative PEST domain variant (S2523L). These phenotypic changes include proliferation, migration, anchorage-independent growth, and MAPK pathway activation. In contrast to previous studies, activating NOTCH1 variants did not display sensitivity to a gamma secretase inhibitor (GSI) or resistance to chemotherapies. This study demonstrates distinct transformative phenotypes are specific to a given variant within NOTCH1 and these phenotypes do not correlate with sensitivities or resistance to chemotherapies or GSIs. Although previous studies have suggested NOTCH1 variants may be prognostic for TNBC, our study does not demonstrate prognostic ability of these variants and suggests further characterization would be required for clinical applications.


Assuntos
Neoplasias de Mama Triplo Negativas , Linhagem Celular Tumoral , Proliferação de Células/genética , Inibidores e Moduladores de Secretases gama , Humanos , Receptor Notch1/genética , Receptor Notch1/metabolismo , Transdução de Sinais , Padrão de Cuidado , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/terapia
16.
J Clin Invest ; 132(23)2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36194476

RESUMO

Testosterone is the canonical growth factor of prostate cancer but can paradoxically suppress its growth when present at supraphysiological levels. We have previously demonstrated that the cyclical administration of supraphysiological androgen (SPA), termed bipolar androgen therapy (BAT), can result in tumor regression and clinical benefit for patients with castration-resistant prostate cancer. However, predictors and mechanisms of response and resistance have been ill defined. Here, we show that growth inhibition of prostate cancer models by SPA required high androgen receptor (AR) activity and were driven in part by downregulation of MYC. Using matched sequential patient biopsies, we show that high pretreatment AR activity predicted downregulation of MYC, improved clinical response, and prolonged progression-free and overall survival for patients on BAT. BAT induced strong downregulation of AR in all patients, which is shown to be a primary mechanism of acquired resistance to SPA. Acquired resistance was overcome by alternating SPA with the AR inhibitor enzalutamide, which induced adaptive upregulation of AR and resensitized prostate cancer to SPA. This work identifies high AR activity as a predictive biomarker of response to BAT and supports a treatment paradigm for prostate cancer involving alternating between AR inhibition and activation.


Assuntos
Neoplasias de Próstata Resistentes à Castração , Receptores Androgênicos , Masculino , Humanos , Receptores Androgênicos/metabolismo , Androgênios/farmacologia , Neoplasias de Próstata Resistentes à Castração/metabolismo , Antagonistas de Receptores de Andrógenos/farmacologia , Antagonistas de Receptores de Andrógenos/uso terapêutico , Nitrilas , Testosterona/farmacologia , Resistencia a Medicamentos Antineoplásicos , Linhagem Celular Tumoral
17.
Cancers (Basel) ; 13(21)2021 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-34771673

RESUMO

Hypoxia occurs in 90% of solid tumors and is associated with treatment failure, relapse, and mortality. HIF-1α signaling promotes resistance to chemotherapy in cancer cell lines and murine models via multiple mechanisms including the enrichment of breast cancer stem cells (BCSCs). In this work, we utilize a hypoxia fate-mapping system to determine whether triple-negative breast cancer (TNBC) cells that experience hypoxia in the primary tumor are resistant to chemotherapy at sites of metastasis. Using two orthotopic mouse models of TNBC, we demonstrate that cells that experience intratumoral hypoxia and metastasize to the lung and liver have decreased sensitivity to doxorubicin and paclitaxel but not cisplatin or 5-FU. Resistance to therapy leads to metastatic recurrence caused by post-hypoxic cells. We further determined that the post-hypoxic cells that metastasize are enriched in pathways related to cancer stem cell gene expression. Overall, our results show that even when hypoxic cancer cells are reoxygenated in the bloodstream they retain a hypoxia-induced cancer stem cell-like phenotype that persists and promotes resistance and eventually recurrence.

18.
Sci Rep ; 11(1): 14925, 2021 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-34290365

RESUMO

Prostate cancer cells are characterized by a remarkably low proliferative rate and the production of high levels of prostate-specific proteases. Protein-based toxins are attractive candidates for prostate cancer therapy because they kill cells via proliferation-independent mechanisms. However, the non-specific cytotoxicity of these potent cytotoxins must be redirected to avoid toxicity to normal tissues. Prostate-Specific Membrane Antigen (PSMA) is membrane-bound carboxypeptidase that is highly expressed by prostate cancer cells. Potent dipeptide PSMA inhibitors have been developed that can selectively deliver and concentrate imaging agents within prostate cancer cells based on continuous PSMA internalization and endosomal cycling. On this basis, we conjugated a PSMA inhibitor to the apoptosis-inducing human protease Granzyme B and the potent Pseudomonas exotoxin protein toxin fragment, PE35. We assessed selective PSMA binding and entrance into tumor cell to induce cell death. We demonstrated these agents selectively bound to PSMA and became internalized. PSMA-targeted PE35 toxin was selectively toxic to PSMA producing cells in vitro. Intratumoral and intravenous administration of this toxin produced marked tumor killing of PSMA-producing xenografts with minimal host toxicity. These studies demonstrate that urea-based PSMA inhibitors represent a simpler, less expensive alternative to antibodies as a means to deliver cytotoxic proteins to prostate cancer cells.


Assuntos
Sistemas de Liberação de Medicamentos , Imunotoxinas/administração & dosagem , Calicreínas , Antígeno Prostático Específico , Neoplasias da Próstata/tratamento farmacológico , Ureia , Carboxipeptidases/metabolismo , Linhagem Celular Tumoral , Humanos , Calicreínas/antagonistas & inibidores , Calicreínas/metabolismo , Masculino , Antígeno Prostático Específico/antagonistas & inibidores , Antígeno Prostático Específico/metabolismo , Neoplasias da Próstata/metabolismo
19.
Folia Med (Plovdiv) ; 63(4): 511-518, 2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-35851172

RESUMO

INTRODUCTION: Gestational hypertension is a less investigated hypertensive disorder of pregnancy than preeclampsia, but evidence exists of an unfavourable cardiovascular profile for women after such a pregnancy. AIM: To determine serum high-sensitivity C-reactive protein (hs-CRP) levels in women with preeclampsia, gestational hypertension, and in normotensive pregnancy in order to assess the cardiovascular implications and to examine its correlations with some characteristics of women. MATERIALS AND METHODS: Thirty-six women with gestational hypertension, thirty-seven with preeclampsia, and fifty maternal and gestational age-matched controls were included in a single-center prospective clinical-epidemiological study. Serum hs-CRP levels were determined using ELISA method. RESULTS: Significantly higher hs-CRP levels were found in the gestational hypertension group than in the controls (p=0.043), but not in the preeclampsia group (p=0.445). The levels between the two pathological groups did not differ significantly (p=0.247). Odds ratio for hs-CRP levels higher than the provided cut-off was 3.31 (95% CI 1.32-8.29) for the presence of gestational hypertension. In the normotensive pregnant women, the hs-CRP levels had a positive correlation with BSA, pre-pregnancy and current BMI, but such correlations were absent in the hypertensive groups. There were no correlations with the maternal or gestational age, current weight gain in any of the groups or with the highest detected blood pressure in the pathological groups. These levels did not differ according to gravidity, smoking status and smoking during pregnancy. CONCLUSIONS: Elevation of hs-CRP was more pronounced in women with gestational hypertension than in women with preeclampsia, which could indicate a different pathophysiological mechanism and a higher cardiovascular risk for those women.


Assuntos
Hipertensão Induzida pela Gravidez , Pré-Eclâmpsia , Pressão Sanguínea , Proteína C-Reativa/metabolismo , Feminino , Humanos , Gravidez , Gestantes , Estudos Prospectivos
20.
J Clin Invest ; 131(6)2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-33529175

RESUMO

Intratumor heterogeneity is an important mediator of poor outcomes in many cancers, including breast cancer. Genetic subclones frequently contribute to this heterogeneity; however, their growth dynamics and interactions remain poorly understood. PIK3CA and HER2 alterations are known to coexist in breast and other cancers. Herein, we present data that describe the ability of oncogenic PIK3CA mutant cells to induce the proliferation of quiescent HER2 mutant cells through a cell contact-mediated mechanism. Interestingly, the HER2 cells proliferated to become the major subclone over PIK3CA counterparts both in vitro and in vivo. Furthermore, this phenotype was observed in both hormone receptor-positive and -negative cell lines, and was dependent on the expression of fibronectin from mutant PIK3CA cells. Analysis of human tumors demonstrated similar HER2:PIK3CA clonal dynamics and fibronectin expression. Our study provides insight into nonrandom subclonal architecture of heterogenous tumors, which may aid the understanding of tumor evolution and inform future strategies for personalized medicine.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Neoplasias da Mama/metabolismo , Comunicação Celular/genética , Linhagem Celular Tumoral , Transformação Celular Neoplásica/genética , Classe I de Fosfatidilinositol 3-Quinases/genética , Técnicas de Cocultura , Feminino , Fibronectinas/antagonistas & inibidores , Fibronectinas/genética , Fibronectinas/metabolismo , Regulação Neoplásica da Expressão Gênica , Frequência do Gene , Técnicas de Inativação de Genes , Humanos , Imuno-Histoquímica , Células MCF-7 , Mutação , Fenótipo , Receptor ErbB-2/genética
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