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Annexin A7/ANXA7 is a calcium-dependent membrane fusion protein with tumor suppressor gene (TSG) properties, which is located on chromosome 10q21 and is thought to function in the regulation of calcium homeostasis and tumorigenesis. However, whether the molecular mechanisms for tumor suppression are also involved in the calcium- and phospholipid-binding properties of ANXA7 remain to be elucidated. We hypothesized that the 4 C-terminal endonexin-fold repeats in ANXA7 (GX(X)GT), which are contained within each of the 4 annexin repeats with 70 amino acids, are responsible for both calcium- and GTP-dependent membrane fusion and the tumor suppressor function. Here, we identified a dominant-negative triple mutant (DNTM/DN-ANXA7J) that dramatically suppressed the ability of ANXA7 to fuse with artificial membranes while also inhibiting tumor cell proliferation and sensitizing cells to cell death. We also found that the [DNTM]ANA7 mutation altered the membrane fusion rate and the ability to bind calcium and phospholipids. In addition, in prostate cancer cells, our data revealed that variations in phosphatidylserine exposure, membrane permeabilization, and cellular apoptosis were associated with differential IP3 receptor expression and PI3K/AKT/mTOR modulation. In conclusion, we discovered a triple mutant of ANXA7, associated with calcium and phospholipid binding, which leads to the loss of several essential functions of ANXA7 pertinent to tumor protection and highlights the importance of the calcium signaling and membrane fusion functions of ANXA7 for preventing tumorigenesis.
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Fosfatidilinositol 3-Quinases , Neoplasias da Próstata , Masculino , Humanos , Receptores de Inositol 1,4,5-Trifosfato/metabolismo , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Cálcio/metabolismo , Sinalização do Cálcio , Neoplasias da Próstata/metabolismo , Proliferação de Células/genética , Linhagem Celular Tumoral , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , CarcinogêneseRESUMO
SARS-CoV-2-contributes to sickness and death in COVID-19 patients partly by inducing a hyper-proinflammatory immune response in the host airway. This hyper-proinflammatory state involves activation of signaling by NFκB, and unexpectedly, ENaC, the epithelial sodium channel. Post-infection inflammation may also contribute to "Long COVID"/PASC. Enhanced signaling by NFκB and ENaC also marks the airway of patients suffering from cystic fibrosis, a life-limiting proinflammatory genetic disease due to inactivating mutations in the CFTR gene. We therefore hypothesized that inflammation in the COVID-19 airway might similarly be due to inhibition of CFTR signaling by SARS-CoV-2 spike protein, and therefore activation of both NFκB and ENaC signaling. We used western blot and electrophysiological techniques, and an organoid model of normal airway epithelia, differentiated on an air-liquid-interface (ALI). We found that CFTR protein expression and CFTR cAMP-activated chloride channel activity were lost when the model epithelium was exposed to SARS-CoV-2 spike proteins. As hypothesized, the absence of CFTR led to activation of both TNFα/NFκB signaling and α and γ ENaC. We had previously shown that the cardiac glycoside drugs digoxin, digitoxin and ouabain blocked interaction of spike protein and ACE2. Consistently, addition of 30 nM concentrations of the cardiac glycoside drugs, prevented loss of both CFTR protein and CFTR channel activity. ACE2 and CFTR were found to co-immunoprecipitate in both basal cells and differentiated epithelia. Thus spike-dependent CFTR loss might involve ACE2 as a bridge between Spike and CFTR. In addition, spike exposure to the epithelia resulted in failure of endosomal recycling to return CFTR to the plasma membrane. Thus, failure of CFTR recovery from endosomal recycling might be a mechanism for spike-dependent loss of CFTR. Finally, we found that authentic SARS-CoV-2 virus infection induced loss of CFTR protein, which was rescued by the cardiac glycoside drugs digitoxin and ouabain. Based on experiments with this organoid model of small airway epithelia, and comparisons with 16HBE14o- and other cell types expressing normal CFTR, we predict that inflammation in the COVID-19 airway may be mediated by inhibition of CFTR signaling by the SARS-CoV-2 spike protein, thus inducing a cystic fibrosis-like clinical phenotype. To our knowledge this is the first time COVID-19 airway inflammation has been experimentally traced in normal subjects to a contribution from SARS-CoV-2 spike-dependent inhibition of CFTR signaling.
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COVID-19 , Regulador de Condutância Transmembrana em Fibrose Cística , Inflamação , SARS-CoV-2 , Transdução de Sinais , Glicoproteína da Espícula de Coronavírus , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Humanos , Glicoproteína da Espícula de Coronavírus/metabolismo , COVID-19/metabolismo , COVID-19/virologia , SARS-CoV-2/fisiologia , Inflamação/metabolismo , NF-kappa B/metabolismo , Canais Epiteliais de Sódio/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Ouabaína/farmacologiaRESUMO
TNFAIP8 is a NF-κB-inducible, oncogenic molecule. Previous "promoter array" studies have identified differential methylation and regulation of TNFAIP8 in prostate epithelial and cancer cell lines. Here we demonstrate that TNFAIP8 expression is induced by androgen in hormone-responsive LNCaP prostate cancer cells. In athymic mice bearing hormone-refractory PC-3 prostate tumor xenografts, intravenous treatment with a liposomal formulation of TNFAIP8 antisense oligonucleotide (LE-AS5) caused reduced expression of TNFAIP8 in tumor tissues, and a combination of LE-AS5 and radiation or docetaxel treatment resulted in significant inhibition of PC-3 tumor growth as compared to single agents. The immunohistochemical evaluation of TNFAIP8 expression revealed correlation of both cytoplasmic and nuclear TNFAIP8 overexpression with high grade prostatic adenocarcinomas, while nuclear overexpression was found to be an independent predictor of disease recurrence controlling for tumor grade. Increased nuclear TNFAIP8 expression was statistically significantly associated with a 2.44 fold (95 % confidence interval: 1.01-5.91) higher risk of prostate cancer recurrence. Mechanistically, TNFAIP8 seems to function as a scaffold (or adaptor) protein. In the antibody microarray analysis of proteins associated with the TNFAIP8 immune-complex, we have identified Karyopherin alpha2 as a novel binding partner of nuclear TNFAIP8 in PC-3 cells. The Ingenuity Pathway Analysis of the TNFAIP8 interacting proteins suggested that TNFAIP8 influences cancer progression pathways and networks involving integrins and matrix metalloproteinases. Taken together, present studies demonstrate that TNFAIP8 is a novel therapeutic target in prostate cancer, and indicate a potential relationship of the nuclear trafficking of TNFAIP8 with adverse outcomes in a subset of prostate cancer patients.
Assuntos
Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/radioterapia , Antineoplásicos/uso terapêutico , Proteínas Reguladoras de Apoptose/metabolismo , Biomarcadores Tumorais/metabolismo , Oligonucleotídeos Antissenso/uso terapêutico , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/radioterapia , Taxoides/uso terapêutico , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Animais , Proteínas Reguladoras de Apoptose/genética , Linhagem Celular Tumoral , Quimioterapia Adjuvante , Progressão da Doença , Docetaxel , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Imuno-Histoquímica , Lipossomos , Masculino , Camundongos , Camundongos Nus , Gradação de Tumores , Oligonucleotídeos Antissenso/síntese química , Valor Preditivo dos Testes , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Análise Serial de Proteínas , Radioterapia Adjuvante , Transplante Heterólogo , Regulação para CimaRESUMO
BACKGROUND: Cardiac glycosides such as digitoxin have been shown to directly cause apoptotic death of cancer cells both in vitro, and in vivo. However, the mechanism connecting cardiac glycoside action to apoptosis is not known. It has been reported that compounds resembling digitoxin are able to reduce c-MYC expression. Furthermore, it has been previously shown that the transcription of c-MYC depends on nuclear factor of activated T-cells (NFAT) binding sites in the c-MYC promoter. We have therefore hypothesized that NFAT might mediate digitoxin effects on c-MYC mRNA message. MATERIALS AND METHODS: We have chosen to study this process in HeLa cells where structurally intact c-MYC genes in 8q24 co-localize with human papilloma virus 18 at all integration sites. RESULTS: Here we show that within the 1(st) h following treatment with digitoxin, a significant reduction in c-MYC mRNA occurs. This is followed by a precipitous loss of c-MYC protein, activation of caspase 3, and subsequent apoptotic cell death. To test the NFAT-dependence mechanism, we analyzed the effects of digitoxin on NFAT isoform-dependent auto-activation of a NFAT-luciferase expression system. Drug dependent effects on expression varied according to each of the four canonical NFAT isoforms (1, 2, 3 or 4). The most digitoxin-sensitive NFAT isoform was NFAT1. Using c-MYC chromatin immune precipitation, we find that digitoxin inhibits interaction of NFAT1 with the proximal c-MYC promoter. CONCLUSIONS: These results suggest that the carcinotoxic activity of digitoxin includes suppression of NFAT-driven c-MYC expression.
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Dynamic post-translational processes regulate protein expression in eukaryotic cells. However, the processes are difficult to assess on a proteomic scale because protein levels actually reflect the sum of individual biosynthesis and degradation rates. These rates are presently hidden from the conventional proteomic technologies. We present here a novel and dynamic, antibody microarray-based time-resolved approach to simultaneously measure not only the total protein changes but also the rates of biosynthesis of low abundance proteins in the proteome of lung epithelial cells. In this chapter, we describe the feasibility of this technique by investigating the complete proteomic kinetics of 507 low abundance proteins in cultured cystic fibrosis (CF) lung epithelial cells using 35[S] methionine or 32[P] and the consequences of repair by gene therapy with [wildtype] CFTR. This novel antibody microarray-based technology identifies relevant, hidden proteins whose regulation by the CF genotype would never have been detected by simple measurements of total proteomic masses.
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Fibrose Cística , Proteoma , Humanos , Proteoma/metabolismo , Proteômica/métodos , Fibrose Cística/metabolismo , Anticorpos/metabolismo , Pulmão/metabolismo , Regulador de Condutância Transmembrana em Fibrose Cística/genéticaRESUMO
To initiate SARS-CoV-2 infection, the Receptor Binding Domain (RBD) on the viral spike protein must first bind to the host receptor ACE2 protein on pulmonary and other ACE2-expressing cells. We hypothesized that cardiac glycoside drugs might block the binding reaction between ACE2 and the Spike (S) protein, and thus block viral penetration into target cells. To test this hypothesis we developed a biochemical assay for ACE2:Spike binding, and tested cardiac glycosides as inhibitors of binding. Here we report that ouabain, digitoxin, and digoxin, as well as sugar-free derivatives digitoxigenin and digoxigenin, are high-affinity competitive inhibitors of ACE2 binding to the Original [D614] S1 and the α/ß/γ [D614G] S1 proteins. These drugs also inhibit ACE2 binding to the Original RBD, as well as to RBD proteins containing the ß [E484K], Mink [Y453F] and α/ß/γ [N501Y] mutations. As hypothesized, we also found that ouabain, digitoxin and digoxin blocked penetration by SARS-CoV-2 Spike-pseudotyped virus into human lung cells, and infectivity by native SARS-CoV-2. These data indicate that cardiac glycosides may block viral penetration into the target cell by first inhibiting ACE2:RBD binding. Clinical concentrations of ouabain and digitoxin are relatively safe for short term use for subjects with normal hearts. It has therefore not escaped our attention that these common cardiac medications could be deployed worldwide as inexpensive repurposed drugs for anti-COVID-19 therapy.
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Enzima de Conversão de Angiotensina 2/metabolismo , Tratamento Farmacológico da COVID-19 , Cardiotônicos/farmacologia , SARS-CoV-2/efeitos dos fármacos , Glicoproteína da Espícula de Coronavírus/metabolismo , Internalização do Vírus/efeitos dos fármacos , Células A549 , Animais , COVID-19/metabolismo , Chlorocebus aethiops , Digitoxina/farmacologia , Digoxina/farmacologia , Humanos , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Ouabaína/farmacologia , Ligação Proteica/efeitos dos fármacos , SARS-CoV-2/fisiologia , Células VeroRESUMO
AIM: The aim of this study was to test for the influence of ascorbic acid on tumorigenicity and metastases of implanted PAIII prostate cancer adenocarcinoma cells in syngeneic LW rats. MATERIALS AND METHODS: Hormone-refractory prostate cancer PAIII cells were implanted subcutaneously into immunologically intact, Lobund-Wistar (LW) rats. Intraperitoneal pharmacological doses of ascorbic acid were administered each day for the ensuing 30 days. On the 40th day, animals were sacrificed. Local tumor weights were measured, and metastases were counted. RESULTS: At the end of the 40 day experimental period, the primary tumors were found to be significantly reduced in weight (p=0.026). In addition, sub-pleural lung metastases were even more profoundly reduced in number and size (p=0.009). Grossly enlarged ipsilateral lymph node metastases declined from 7 of 15 rats to 1 of 15 rats. CONCLUSION: Pharmacological doses of ascorbic acid suppress tumor growth and metastases in hormone-refractory prostate cancer.
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Adenocarcinoma/tratamento farmacológico , Antioxidantes/farmacologia , Ácido Ascórbico/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias da Próstata/tratamento farmacológico , Adenocarcinoma/secundário , Animais , Peso Corporal , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Neoplasias Pulmonares/secundário , Metástase Linfática , Masculino , Transplante de Neoplasias , Neoplasias da Próstata/patologia , Curva ROC , Ratos , Ratos WistarRESUMO
INTRODUCTION: Biopsy of the allograft is the gold standard for assessing kidney allograft dysfunction. The aim of our pilot study was to identify serum biomarkers that could obviate the need for biopsy. MATERIALS AND METHODS: We conducted a study to identify the biomarkers in the serum from different groups of chronic kidney disease (CKD) patients and kidney transplanted patients vs. healthy individuals. The four groups (n=25 in each group) were as follows: 1) Patients with unstable kidney allograft transplants requiring biopsy for cause, 2) Patients with stable kidney allograft transplants, 3) Patients with CKD not on immunosuppressive therapy and, 4) healthy subjects. We measured the activity and level of serum alkaline phosphatase (ALP) and other liver enzymes (alanine transaminase (ALT) and aspartate transaminase (AST)) as potential serum biomarkers in acute allograft dysfunction. RESULTS: We found that ALP correlated with allograft biopsy findings, liver function, and clinical outcomes and possibly graft survival. Additionally, AST and ALT were higher in patients with graft rejection compared to non-rejected and stable kidney transplants. Moreover, the low Pearson correlations (r- values) between ALP level with age (r=0.179), gender, body mass index (r=0.236), creatinine (r=0.044) or estimated glomerular filtration rate (r=0.048) suggest that ALP may be an independent biomarker which is relatively unaffected by other individual-level variables. CONCLUSION: ALP may be a putative biomarker to predict kidney allograft function and rejection. Data also indicated that liver function plays an important role for the overall success of kidney transplantation.
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INTRODUCTION: Breast cancer is the most frequent cancer detected for women, and while our ability to treat breast cancer has improved substantially over the years, recurrence remains a major obstacle. Standard screening for new and recurrent breast cancer involves clinical breast imaging. However, there is no clinically approved noninvasive body fluid test for the early detection of recurrent breast cancer. Materials and Method: In this study, we analyzed serum samples from both recurrent and nonrecurrent breast cancer patients by different proteomics methods to identify biomarkers in patients with recurrence of disease. RESULTS: Comparative data analysis identified several histone deacetylase (HDAC) proteins, which were found at significantly higher levels in the serum of recurrent breast cancer patients: HDAC9 (C-term) (P = 0.0035), HDAC5 (C-term) (P = 0.013), small ubiquitin-like modifier 1 (N-term) (P = 0.017), embryonic stem cell-expressed Ras (inter) (P = 0.018), and HDAC7 (C-term) (P = 0.020). Chronic inflammation plays a critical role in the development of the breast cancer recurrence, and we identified several proinflammatory cytokines that were present at elevated levels only in recurrent breast cancer patient serum. CONCLUSIONS: Our data indicated that the epigenetic regulation of inflammatory processes plays a critical role in breast cancer recurrence. The identified proteins could lay the groundwork for the development of a serum-based breast cancer recurrence assay.
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Neoplasias da Mama/genética , Inflamação/genética , Proteômica/métodos , Adulto , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/genética , Neoplasias da Mama/complicações , Feminino , Histona Desacetilases/análise , Humanos , Pessoa de Meia-Idade , Proteômica/estatística & dados numéricos , RecidivaRESUMO
African American (AA) women are often diagnosed with more aggressive breast cancers and have worse survival outcomes than their Caucasian American (CA) counterparts. However, a comprehensive understanding of this disparity remains unclear. In this study, we attempted to identify the race-specific non-invasive protein biomarkers that may particularly benefit interventions aimed at reducing the risk of recurrence and metastasis in breast cancers (BrCa). Our technical strategy has been to discover candidate protein biomarkers in patient sera using a high throughput antibody microarray platform. A total of 240 subjects were selected, composed of controls and all immunohistochemistry-based subtypes of breast cancer cases, subdivided by pre- and post-menopausal status and by race. A global Wilcoxon analysis comparing no-cancer controls and cancer patients identified Pyk2, SAPK/JNK, and phosphatase and tensin homolog as present in higher concentrations in cancer patient serum. A paired t-test revealed that c-kit and Rb are significantly over-represented in AA cancer serum when compared to CA cancer serum. Interestingly, VEGFR2, a protein linked to BrCa metastasis and poor prognosis, was significantly over-represented in AA cancer serum compared to AA controls; however, this was not found in CA cancer serum compared to CA controls, suggesting a possible explanation for the higher incidence of aggressive BrCa in AA versus CA patients. Through examining race-specific differences in the protein landscape of BrCa patient serum, the identified proteins could lay the groundwork for the development of an all-inclusive "liquid mammogram test."
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Biomarcadores/sangue , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/fisiopatologia , Disparidades nos Níveis de Saúde , Grupos Raciais/estatística & dados numéricos , Adulto , Negro ou Afro-Americano/genética , Idoso , Biomarcadores/análise , Neoplasias da Mama/classificação , Feminino , Predisposição Genética para Doença/genética , Humanos , Incidência , Pessoa de Meia-IdadeRESUMO
Castration Resistant Prostate Cancer (CRPC) is thought to be driven by a collaborative mechanism between TNFα/NFκB and TGFß signaling, leading to inflammation, Epithelial-to-Mesenchymal-Transition (EMT), and metastasis. Initially, TGFß is a tumor suppressor, but in advanced metastatic disease it switches to being a tumor promoter. TGFBR2 may play a critical role in this collaboration, as its expression is driven by NFκB and it is the primary receptor for TGFß. We have previously reported that the cardenolide drug digitoxin blocks TNFα/NFκB-driven proinflammatory signaling. We therefore hypothesized that digitoxin might break the collaborative process between NFκB and TGFß by also inhibiting expression of TGFBR2. We therefore tested whether TGFß-driven EMT and resulting metastases would be suppressed. Here we show, in vitro, that digitoxin inhibits NFκB-driven TGFBR2 expression, as well as Vimentin, while elevating E-cadherin expression. Digitoxin also significantly reduces HSPB1 mRNA and the HSPB1/RBFOX2 mRNA ratio in PC3 cells. In vivo, in a syngeneic, immune competent rat model of metastatic CRPC, we show that digitoxin also suppresses Tgfbr2 expression, as well as expression of other genes classically driven by NFκB, and of multiple EMT genes associated with metastasis. Concurrently, digitoxin suppresses tumor growth and metastasis in these animals, and prolongs survival. Gross tumor recurrence following tumor resection also appears prevented in ca 30% of cases. While the existence of a collaboration between NFκB and TGFß to drive EMT and metastasis has previously been appreciated, we show here, for the first time, that chronic, low concentrations of digitoxin are able to block CRPC tumor progression, EMT and the ensuing metastatic disease.
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BACKGROUND/AIM: Our studies showed that ANXA7 is a novel tumor suppressor gene that is lost in various aggressive forms of prostate cancer. However, little is known about the role of ANXA7 in the anticancer drug treatment towards different cancers. MATERIALS AND METHODS: The expression of ANXA7 was measured in the 60 cancer cell lines of the NCI-60 ADS project and correlated with the enhanced sensitivity to over 30,000 natural and synthetic compounds. RESULTS: Eucalyptol showed a high positive correlation with ANXA7 expression and castration-resistant prostate cancer cell death occurred very effectively in response to the combination of eucalyptol and overexpressed wt-ANXA7 than either agent alone. The synergistic effects of ANXA7 and eucalyptol resulted in concordant changes in gene expression profiles particularly of Ras family members, MDM4, NF-ĸB and VEGF. CONCLUSION: Overexpression of ANXA7 enhances eucalyptol cytotoxicity in prostate cancer cell lines.
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Anexina A7/genética , Cicloexanóis/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Monoterpenos/farmacologia , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Linhagem Celular Tumoral , Proliferação de Células , Cicloexanóis/uso terapêutico , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Eucaliptol , Perfilação da Expressão Gênica , Humanos , Masculino , Monoterpenos/uso terapêutico , Neoplasias de Próstata Resistentes à Castração/genética , Neoplasias de Próstata Resistentes à Castração/patologiaRESUMO
BACKGROUND: Annexin A7 (ANXA7) is a member of the multifunctional calcium or phospholipid-binding annexin gene family. While low levels of ANXA7 are associated with aggressive types of cancer, the clinical impact of ANXA7 in prostate cancer remains unclear. Tissue microarrays (TMA) have revealed several new molecular markers in human tumors. Herein, we have identified the prognostic impact of ANXA7 in a prostate cancer using a tissue microarray containing 637 different specimens. METHODS: The patients were diagnosed with prostate cancer and long-term follow-up information on progression (median 5.3 years), tumor-specific and overall survival data (median 5.9 years) were available. Expression of Ki67, Bcl-2, p53, CD-10 (neutral endopeptidase), syndecan-1 (CD-138) and ANXA7 were analyzed by immunohistochemistry. RESULTS: A bimodal distribution of ANXA7 was observed. Tumors expressing either high or no ANXA7 were found to be associated with poor prognosis. However, ANXA7 at an optimal level, in between high and no ANXA7 expression, had a better prognosis. This correlated with low Ki67, Bcl-2, p53 and high syndecan-1 which are known predictors of early recurrence. At Gleason grade 3, ANXA7 is an independent predictor of poor overall survival with a p-value of 0.003. Neoadjuvant hormonal therapy, which is known to be associated with overexpression of Bcl-2 and inhibition of Ki67 LI and CD-10, was found to be associated with under-expression of ANXA7. CONCLUSIONS: The results of this TMA study identified ANXA7 as a new prognostic factor and indicates a bimodal correlation to tumor progression.
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Anexina A7/sangue , Neoplasias da Próstata/sangue , Análise Serial de Tecidos/métodos , Idoso , Idoso de 80 Anos ou mais , Progressão da Doença , Humanos , Estimativa de Kaplan-Meier , Antígeno Ki-67/metabolismo , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Neprilisina/metabolismo , Prognóstico , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/patologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Sindecana-1/metabolismo , Fatores de Tempo , Resultado do TratamentoRESUMO
Tumor suppressor function of ubiquitously expressed Annexin-A7, ANXA7 (10q21) that is involved in exocytosis and membrane fusion was based on cancer prone phenotype in Anxa7(+/-) mice as well as ANXA7 role in human prostate and breast cancers. To clarify ANXA7 biomarker and tumor suppressor function, we analyzed its expression pattern in comparison to the prostate-specific biomarker NKX3.1. Immunohistochemistry-based ANXA7 and NKX3.1 protein expression was analyzed on human tissue microarrays of 4,061 specimens from a wide spectrum of the histopathologically well-characterized tumors in different stages compared to corresponding normal tissues. Decreased ANXA7 expression was mostly associated with high invasive potential in multiple tumors. Although some metastases retained relatively high ANXA7 rates compared to primary cancer tissues, the lymph node metastases from different sites (including prostate and breast) had decreased ANXA7 expression in comparison to the intact lymphatic tissues. Major ANXA7 downregulation pattern was deviated in tumors of glandular (especially neuroendocrine) origin. ANXA7 and NKX3.1 proteins were synexpressed in the male urogenital system and adrenal gland. Gene expression profiling in prostate and breast cancers (SMD) revealed distinct hormone-related profiles for NKX3.1 and ANXA7, where ANXA7 expression correlated with steroid sulfatase which has a pivotal role in steroidogenesis. Abundant protein presence in adrenal gland and its loss in hormone-refractory prostate cancer indicated that ANXA7 can be relevant to steroidogenesis and androgen sensitivity in particular. With tumor suppressor pattern validated in different tumors, ANXA7 can be an attractive diagnostic and therapeutic target associated with the hormone and/or neurotransmitter-mediated modulation of tumorigenesis.
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Anexina A7/análise , Biomarcadores Tumorais/análise , Neoplasias da Mama/química , Neoplasias da Mama/patologia , Neoplasias Hormônio-Dependentes/química , Neoplasias Hormônio-Dependentes/patologia , Neoplasias da Próstata/química , Neoplasias da Próstata/patologia , Animais , Regulação para Baixo , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Proteínas de Homeodomínio/análise , Humanos , Imuno-Histoquímica , Metástase Linfática , Masculino , Camundongos , Invasividade Neoplásica , Análise Serial de Proteínas , Análise Serial de Tecidos , Fatores de Transcrição/análiseRESUMO
Chromosomal abnormalities, including homozygous deletions and loss of heterozygosity at 10q, are commonly observed in most human tumors, including prostate, breast, and kidney cancers. The ANXA7-GTPase is a tumor suppressor, which is frequently inactivated by genomic alterations at 10q21. In the last few years, considerable amounts of data have accumulated describing inactivation of ANXA7-GTPase in a variety of human malignancies and demonstrating the tumor suppressor potential of ANXA7-GTPase. ANXA7-GTPase contains a calcium binding domain that classifies it as a member of the annexin family. The cancer-specific expression of ANXA7-GTPase, coupled with its importance in regulating cell death, cell motility, and invasion, makes it a useful diagnostic marker of cancer and a potential target for cancer treatment. Recently, emerging evidence suggests that ANXA7-GTPase is a critical factor associated with the metastatic state of several cancers and can be used as a risk biomarker for HER2 negative breast cancer patients. Cross talk between ANXA7, PTEN, and EGFR leads to constitutive activation of PI3K-AKT signaling, a central pathway of tumor cell survival and proliferation. This review focuses on the recent progress in understanding the tumor suppressor functions of ANXA7-GTPase emphasizing the role of this gene in Ca2+ metabolism, and exploring opportunities for function as an example of a calcium binding GTPase acting as a tumor suppressor and opportunities for ANXA7-GTPase gene cancer therapy.
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Anexina A7/genética , Neoplasias da Mama/terapia , Regulação Neoplásica da Expressão Gênica , Terapia Genética/métodos , Neoplasias Renais/terapia , Neoplasias da Próstata/terapia , Anexina A7/agonistas , Anexina A7/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Cálcio/metabolismo , Cromossomos Humanos Par 10 , Receptores ErbB/genética , Receptores ErbB/metabolismo , Feminino , Vetores Genéticos/uso terapêutico , Humanos , Neoplasias Renais/genética , Neoplasias Renais/metabolismo , Neoplasias Renais/patologia , Perda de Heterozigosidade , Masculino , PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/metabolismo , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Transdução de SinaisRESUMO
Genomics has revolutionized large-scale and high-throughput sequencing and has led to the discovery of thousands of new proteins. Protein chip technology is emerging as a miniaturized and highly parallel platform that is suited to rapid, simultaneous screening of large numbers of proteins and the analysis of various protein-binding activities, enzyme substrate relationships, and posttranslational modifications. Specifically, reverse capture protein microarrays provide the most appropriate platform for identifying low-abundance, disease-specific biomarker proteins in a sea of high-abundance proteins from biological fluids such as blood, serum, plasma, saliva, urine, and cerebrospinal fluid as well as tissues and cells obtained by biopsy. Samples from hundreds of patients can be spotted in serial dilutions on many replicate glass slides. Each slide can then be probed with one specific antibody to the biomarker of interest. That antibody's titer can then be determined quantitatively for each patient, allowing for the statistical assessment and validation of the diagnostic or prognostic utility of that particular antigen. As the technology matures and the availability of validated, platform-compatible antibodies increases, the platform will move further into the desirable realm of discovery science for detecting and quantitating low-abundance signaling proteins. In this chapter, we describe methods for the successful application of the reverse capture protein microarray platform for which we have made substantial contributions to the development and application of this method, particularly in the use of body fluids other than serum/plasma.
Assuntos
Impressão/métodos , Análise Serial de Proteínas/métodos , Processamento de Proteína Pós-Traducional , Proteínas/análise , Proteômica/métodos , Anticorpos/química , Biomarcadores/sangue , Biomarcadores/líquido cefalorraquidiano , Biomarcadores/urina , Líquidos Corporais/química , Humanos , Cultura Primária de Células , Impressão/instrumentação , Análise Serial de Proteínas/instrumentação , Proteínas/metabolismo , Proteômica/instrumentação , Estudos de Validação como AssuntoRESUMO
Tumor necrosis factor-α-inducible protein 8 (TNFAIP8) is the first discovered oncogenic and an anti-apoptotic member of a conserved TNFAIP8 or TIPE family of proteins. TNFAIP8 mRNA is induced by NF-kB, and overexpression of TNFAIP8 has been correlated with poor prognosis in many cancers. Downregulation of TNFAIP8 expression has been associated with decreased pulmonary colonization of human tumor cells, and enhanced sensitivities of tumor xenografts to radiation and docetaxel. Here we have investigated the effects of depletion of TNFAIP8 on the mRNA, microRNA and protein expression profiles in prostate and breast cancers and melanoma. Depending on the tumor cell type, knockdown of TNFAIP8 was found to be associated with increased mRNA expression of several antiproliferative and apoptotic genes (e.g., IL-24, FAT3, LPHN2, EPHA3) and fatty acid oxidation gene ACADL, and decreased mRNA levels of oncogenes (e.g., NFAT5, MALAT1, MET, FOXA1, KRAS, S100P, OSTF1) and glutamate transporter gene SLC1A1. TNFAIP8 knockdown cells also exhibited decreased expression of multiple onco-proteins (e.g., PIK3CA, SRC, EGFR, IL5, ABL1, GAP43), and increased expression of the orphan nuclear receptor NR4A1 and alpha 1 adaptin subunit of the adaptor-related protein complex 2 AP2 critical to clathrin-mediated endocytosis. TNFAIP8-centric molecules were found to be predominately implicated in the hypoxia-inducible factor-1α (HIF-1α) signaling pathway, and cancer and development signaling networks. Thus TNFAIP8 seems to regulate the cell survival and cancer progression processes in a multifaceted manner. Future validation of the molecules identified in this study is likely to lead to new subset of molecules and functional determinants of cancer cell survival and progression.
Assuntos
Proteínas Reguladoras de Apoptose/genética , Neoplasias da Mama/genética , Regulação Neoplásica da Expressão Gênica , Melanoma/genética , Neoplasias da Próstata/genética , Proteômica/métodos , Sequência de Aminoácidos , Proteínas Reguladoras de Apoptose/antagonistas & inibidores , Proteínas Reguladoras de Apoptose/metabolismo , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Sobrevivência Celular , Progressão da Doença , Transportador 3 de Aminoácido Excitatório/genética , Transportador 3 de Aminoácido Excitatório/metabolismo , Feminino , Humanos , Masculino , Melanoma/diagnóstico , Melanoma/metabolismo , Melanoma/patologia , NF-kappa B/genética , NF-kappa B/metabolismo , Proteínas Oncogênicas/genética , Proteínas Oncogênicas/metabolismo , Prognóstico , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Transdução de SinaisRESUMO
"Soldier's Heart," is an American Civil War term linking post-traumatic stress disorder (PTSD) with increased propensity for cardiovascular disease (CVD). We have hypothesized that there might be a quantifiable genetic basis for this linkage. To test this hypothesis we identified a comprehensive set of candidate risk genes for PTSD, and tested whether any were also independent risk genes for CVD. A functional analysis algorithm was used to identify associated signaling networks. We identified 106 PTSD studies that report one or more polymorphic variants in 87 candidate genes in 83,463 subjects and controls. The top upstream drivers for these PTSD risk genes are predicted to be the glucocorticoid receptor (NR3C1) and Tumor Necrosis Factor alpha (TNFA). We find that 37 of the PTSD candidate risk genes are also candidate independent risk genes for CVD. The association between PTSD and CVD is significant by Fisher's Exact Test (P = 3 × 10-54). We also find 15 PTSD risk genes that are independently associated with Type 2 Diabetes Mellitus (T2DM; also significant by Fisher's Exact Test (P = 1.8 × 10-16). Our findings offer quantitative evidence for a genetic link between post-traumatic stress and cardiovascular disease, Computationally, the common mechanism for this linkage between PTSD and CVD is innate immunity and NFκB-mediated inflammation.
RESUMO
Cystic fibrosis (CF) is a common, lethal genetic disease, which is due to mutations in the CFTR gene. The CF lung expresses a profoundly proinflammatory phenotype, due to constitutive hypersecretion of IL-8 from epithelial cells lining the airways. In a systematic search for candidate drugs that might be used therapeutically to suppress IL-8 secretion from these cells, we have identified a potent and efficacious series of amphiphilic pyridinium salts. The most potent of these salts is MRS2481, an (R)-1-phenylpropionic acid ester, with an IC50 of ca. 1microM. We have synthesized 21 analogues of MRS2481, which have proven sufficient to develop a preliminary structure-activity relationship (SAR). For optimal activity, we have found that the ester must be connected to the pyridinium derivative by an eight-carbon chain. An optical isomer of the lead compound, containing an (S)-1-phenylpropionic acid ester, has been found to be a much less active. The mechanism of action of MRS2481 appears to involve inhibition of signaling of the NF(kappa)B and AP-1 transcription factors to the IL-8 promoter. MRS2481 is a potent inhibitor of TNFalpha-induced phosphorylation and proteosomal destruction of I(kappa)B(alpha). Inasmuch as I(kappa)B(alpha) is the principal inhibitor of the NF(kappa)B signaling pathway, preservation of intact I(kappa)B(alpha) would serve to keep the IL-8 promoter silent. We also find that MRS2481 blocks TNF(alpha)-activated phosphorylation of JNK, the c-JUN kinase. The IL-8 promoter is also activated by an AP-1 site, which requires a phospho-c-JUN/c-FOS dimer for activity. We therefore interpret these data to suggest that the mechanism of MRS2481 action is to inhibit both NF(kappa)B and AP-1 signaling on the IL-8 promoter. Given the medicinally promising properties of water-solubility, potency in the low muM concentration range, and high efficacy, we anticipate that MRS2481, or a further optimized derivative, may find an important place in the armamentarium of pharmaceutical strategies yet to be arrayed against the inflammatory phenotype of the CF lung.
Assuntos
Fibrose Cística/metabolismo , Interleucina-8/antagonistas & inibidores , Interleucina-8/metabolismo , NF-kappa B/antagonistas & inibidores , Mucosa Respiratória/efeitos dos fármacos , Mucosa Respiratória/metabolismo , Tensoativos/farmacologia , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fibrose Cística/tratamento farmacológico , Relação Dose-Resposta a Droga , Células HeLa , Humanos , NF-kappa B/fisiologia , Compostos de Piridínio/química , Compostos de Piridínio/farmacologia , Compostos de Piridínio/uso terapêutico , Mucosa Respiratória/fisiologia , Sais/química , Sais/farmacologia , Sais/uso terapêutico , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Tensoativos/química , Tensoativos/uso terapêutico , Fator de Necrose Tumoral alfa/fisiologiaRESUMO
PURPOSE: ANX7-GTPase located on chromosome 10q21 is significantly altered and associated with hormone-refractory metastatic prostate cancers. Therefore, we investigated whether levels of ANX7 correlate with breast cancer progression and survival EXPERIMENTAL DESIGN: A diagnostic tumor tissue microarray containing 525 human breast tissue specimens at different stages of the disease was assayed for ANX7 using immunocytochemical methods with ANX7 monoclonal antibody. A separate prognostic tumor tissue microarray containing 553 human breast tissue specimens annotated with clinicopathological parameters was assayed for ANX7, HER2, estrogen receptor, progesterone receptor, and p53 protein. RESULTS: We report here for the first time that the expression of ANX7-GTPase is significantly enhanced and associated with the presence of metastatic disease (P < 0.0001) in the 525 human breast tissue specimens analyzed. Furthermore, using a separate 553 case retrospective prognostic tumor tissue microarray, we found that increased ANX7 expression is also significantly associated with poor overall patient survival (P < 0.014). This is particularly true when restricted to patients in whom the BRE clinical grade is 2 (P < 0.001) or for whom there is a lack of HER2 expression (P < 0.002). Finally, Cox regression analysis shows that as the expression of ANX7 rises, the probability of survival decreases by more than 10-fold for those patients with HER2-negative tumors. These latter patients represented 66% of the population affected with breast cancer in this study. CONCLUSIONS: High levels of ANX7 in tumor correlate strongly with poor survival of HER2-negative patients and the most aggressive forms of breast cancer. This is the first study to demonstrate that ANX7 antibody has the potential for development into an in vivo diagnostic and therapeutic tool. This simple and reliable immunohistochemical assay may therefore become an important biomarker for metastatic breast cancer diagnosis and management of HER2-negative breast tumor patients.