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BACKGROUND: Cervical cancer is the third most common cancer among women worldwide, but particularly affects women living in sub-Saharan Africa. Screening and vaccination programs are two prevention approaches that can reduce cervical cancer incidence. However, effective vaccination campaigns require better knowledge of the prevalence of the main human papillomavirus (HPV) genotypes reported in high-grade neoplastic lesions and invasive carcinomas in women. METHODS: All samples collected in this study were processed using standard histopathological methods with haematoxylin and eosin staining of the sections. Areas with abnormal cells were then identified. The HPV genotype was determined on the DNA extracted from the same sections using nested PCR followed by amplicon sequencing and real-time PCR specific to five different HPV genotypes (16, 18, 33, 45 and 58). RESULTS: A total of 132 Gabonese patients with high-grade neoplastic lesions were included in this study; 81% were squamous cell carcinomas (SCC). At least one HPV was detected in 92.4% patients; HPV16 (75.4%) was the most frequent genotype, followed by HPV18, 58, 45, 33 and 35. Moreover, histological analysis showed that SCC samples had 50% and 58.2% stage III and IV tumor cells, respectively, according to the FIGO classification. Finally, 36.9% of these stage III and IV patients were less than 50 years old. CONCLUSIONS: Our results confirm the high prevalence of HPV16 and 18 genotypes among high-grade lesions in Gabonese women. This study confirms the need for a national strategy for early screening of precancerous lesions associated with a broad national vaccination program among non-sexually active women to significantly reduce the long-term cancer burden.
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Early predictions forecasted large numbers of severe acute respiratory syndrome coronavirus (SARS-CoV-2) cases and associated deaths in Africa. To date, Africa has been relatively spared. Various hypotheses were postulated to explain the lower than anticipated impact on public health in Africa. However, the contribution of pre-existing immunity is yet to be investigated. In this study, the presence of antibodies against SARS-CoV-2 spike (S) and nucleocapsid (N) proteins in pre-pandemic samples from Africa, Europe, South and North America was examined by ELISA. The protective efficacy of N specific antibodies isolated from Central African donors was tested by in vitro neutralization and in a mouse model of SARS-CoV-2 infection. Antibodies against SARS-CoV-2 S and N proteins were rare in all populations except in Gabon and Senegal where N specific antibodies were prevalent. However, these antibodies failed to neutralize the virus either in vitro or in vivo. Overall, this study indicates that cross-reactive immunity against SARS-CoV-2 N protein was present in Africa prior to the pandemic. However, this pre-existing humoral immunity does not impact viral fitness in rodents suggesting that other human immune defense mechanisms could be involved. In Africa, seroprevalence studies using the N protein are over-estimating SARS-CoV-2 circulation.
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COVID-19 , Animales , Anticuerpos Neutralizantes , Anticuerpos Antivirales , COVID-19/epidemiología , Humanos , Ratones , Pandemias , SARS-CoV-2 , Senegal , Estudios Seroepidemiológicos , Glicoproteína de la Espiga del CoronavirusRESUMEN
Serology-based diagnosis remains one of the major tools for diagnosis and surveillance of infectious diseases. However, for many neglected diseases no or only few commercial assays are available and often with prices prohibiting large scale testing in low and middle-income countries (LMICs). We developed an adaptable enzyme-linked immunoassay (ELISA) using hepatitis C virus (HCV) as a proof-of-concept application. By combining the maltose-binding-protein with a multiepitope HCV protein, we were able to obtain a high concentration of protein suitable for downstream applications. Following optimization, the assay was verified using previously tested human samples from Canada, Denmark and Gabon in parallel with the use of a commercial protein. Sensitivity and specificity were calculated to 98 % and 97 % respectively, after accounting for non-specific binding and assay optimization. This study provides a thorough description of the development, and validation of a multiepitope ELISA-based diagnostic assay against HCV, which could be implemented at low cost. The described methodology can be readily adapted to develop novel ELISA-based diagnostic assays for other infectious pathogens with well-described immunogenic epitopes. This method could improve the diagnosis of neglected diseases for which affordable diagnostic assays are lacking.
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Hepacivirus , Hepatitis C , Ensayo de Inmunoadsorción Enzimática/métodos , Hepatitis C/diagnóstico , Anticuerpos contra la Hepatitis C , Antígenos de la Hepatitis C , Humanos , Enfermedades Desatendidas , Sensibilidad y EspecificidadRESUMEN
Human papillomavirus (HPV) is recognised as the cause of precancerous and cancerous cervical lesions. Furthermore, in high-grade lesions, HPV is frequently integrated in the host cell genome and associated with the partial or complete loss of the E1 and E2 genes, which regulate the activity of viral oncoproteins E6 and E7. In this study, using a double-capture system followed by high-throughput sequencing, we determined the HPV integration status present in liquid-based cervical smears in an urban Gabonese population. The main inclusion criteria were based on cytological grade and the detection of the HPV16 genotype using molecular assays. The rate of HPV integration in the host genome varied with cytological grade: 85.7% (6/7), 71.4% (5/7), 66.7% (2/3) 60% (3/5) and 30.8% (4/13) for carcinomas, HSIL, ASCH, LSIL and ASCUS, respectively. For high cytological grades (carcinomas and HSIL), genotypes HPV16 and 18 represented 92.9% of the samples (13/14). The integrated form of HPV16 genotype was mainly found in high-grade lesions in 71.4% of samples regardless of cytological grade. Minority genotypes (HPV33, 51, 58 and 59) were found in LSIL samples, except HPV59, which was identified in one HSIL sample. Among all the HPV genotypes identified after double capture, 10 genotypes (HPV30, 35, 39, 44, 45, 53, 56, 59, 74 and 82) were detected only in episomal form. Our study revealed that the degree of HPV integration varies with cervical cytological grade. The integration event might be a potential clinical prognostic biomarker for the prediction of the progression of neoplastic lesions.
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Citodiagnóstico/métodos , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Papillomaviridae/aislamiento & purificación , Infecciones por Papillomavirus/complicaciones , Displasia del Cuello del Útero/virología , Neoplasias del Cuello Uterino/virología , Integración Viral/genética , ADN Viral/análisis , ADN Viral/genética , Femenino , Gabón/epidemiología , Genotipo , Humanos , Incidencia , Papillomaviridae/genética , Infecciones por Papillomavirus/genética , Infecciones por Papillomavirus/virología , Análisis de Secuencia de ADN/métodos , Neoplasias del Cuello Uterino/epidemiología , Neoplasias del Cuello Uterino/genética , Neoplasias del Cuello Uterino/patología , Displasia del Cuello del Útero/epidemiología , Displasia del Cuello del Útero/genética , Displasia del Cuello del Útero/patologíaRESUMEN
BACKGROUND: Cervical cancer is the fourth most common malignancy in women worldwide. However, screening with human papillomavirus (HPV) molecular tests holds promise for reducing cervical cancer incidence and mortality in low- and middle-income countries. The performance of the Abbott RealTime High-Risk HPV test (AbRT) was evaluated in 83 cervical smear specimens and compared with a conventional nested PCR coupled to high-throughput sequencing (HTS) to identify the amplicons. RESULTS: The AbRT assay detected at least one HPV genotype in 44.57% of women regardless of the grade of cervical abnormalities. Except for one case, good concordance was observed for the genotypes detected with the AbRT assay in the high-risk HPV category determined with HTS of the amplicon generated by conventional nested PCR. CONCLUSIONS: The AbRT test is an easy and reliable molecular tool and was as sensitive as conventional nested PCR in cervical smear specimens for detection HPVs associated with high-grade lesions. Moreover, sequencing amplicons using an HTS approach effectively identified the genotype of the hrHPV identified with the AbRT test.
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Técnicas de Diagnóstico Molecular/métodos , Técnicas de Diagnóstico Molecular/normas , Papillomaviridae/genética , Infecciones por Papillomavirus/virología , Adulto , Anciano , Anciano de 80 o más Años , Cuello del Útero/virología , ADN Viral/análisis , Femenino , Gabón , Genotipo , Secuenciación de Nucleótidos de Alto Rendimiento , Papillomavirus Humano 16/genética , Papillomavirus Humano 18/genética , Humanos , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa Multiplex , Papillomaviridae/clasificación , Papillomaviridae/aislamiento & purificación , Infecciones por Papillomavirus/diagnóstico , Reacción en Cadena de la Polimerasa , Sensibilidad y Especificidad , Neoplasias del Cuello Uterino/virología , Frotis VaginalRESUMEN
BACKGROUND: The human papillomavirus (HPV) is the causative agent of cervical cancer, which is the leading cancer-related cause of death for women in Sub-Saharan Africa. In 2013, the Gabonese Ministry of Health and the Sylvia Bongo Ondimba Foundation implemented cervical cancer screening programs based on the detection of cancerous lesions by visual inspection with acetic acid and/or Lugol's iodine (VIA/VILI). This pilot study was set up to determine the HPV profile and analyze the nucleotide sequence variation of HPV16 circulating in patients with cervical abnormalities detected by VIA/VILI testing. METHODS: The cervical abnormalities observed upon VIA/VILI were confirmed by liquid-based cytology for all tested women. Nested PCR using the MY09/11 and GP5+/6+ primer sets was used to detect HPVs present in the extracted DNA. HPV genotypes were determined after sequencing of amplicons based on a high-throughput sequencing approach. For isolates of the HPV16 genotype, the E6 gene and the long control region (LCR) were directly sequenced using Sanger method. RESULTS: The study included 87 women who showed a positive VIA/VILI result. Cervical abnormalities were found in 40.23 % of women and 40 % were classified as high-grade lesions. The HPV detection rate was 82.9 % among women with abnormal cytology. Among all the identified high-risk HPV genotypes, HPV16, 18 and 33 were the most frequent. Multiple HPV infections were observed in 42.31 % of HPV-infected women. Analysis of the HPV16 sequence variation in the E6 gene and in the LCR showed that 85.3 and 14.7 % belonged to the African and European lineages, respectively. Among the African branch variants, Af2 was the most frequently identified in this study. CONCLUSION: This study offers the first report of the HPV detection rate and molecular epidemiology among Gabonese women with a positive result in a VIA/VILI screening test. Moreover, data on the HPV16 sequence variation confirm the predominance of African variants in high-grade lesions.
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Colposcopía/métodos , Displasia del Cuello del Útero/diagnóstico , Neoplasias del Cuello Uterino/diagnóstico , Ácido Acético , Adolescente , Adulto , Anciano , Biopsia , Femenino , Gabón/epidemiología , Humanos , Indicadores y Reactivos , Yoduros , Persona de Mediana Edad , Prueba de Papanicolaou/métodos , Valor Predictivo de las Pruebas , Sensibilidad y Especificidad , Displasia del Cuello del Útero/epidemiología , Displasia del Cuello del Útero/patología , Neoplasias del Cuello Uterino/epidemiología , Neoplasias del Cuello Uterino/patología , Frotis Vaginal/métodos , Adulto JovenRESUMEN
Loss of the tumor suppressor PTEN is a common occurrence in prostate cancer. This aberration leads to the ectopic activation of the PI3K-Akt pathway, which promotes tumor growth. Here, we show that the transcription factor Gata3 is progressively lost in Pten-deficient mouse prostate tumors as a result of both transcriptional down-regulation and increased proteasomal degradation. To determine the significance of this loss, we used conditional loss- and gain-of-function approaches to manipulate Gata3 expression levels in prostate tumors. Our results show that Gata3 inactivation in Pten-deficient prostates accelerates tumor invasion. Conversely, enforced expression of GATA3 in Pten-deficient tissues markedly delays tumor progression. In Pten-deficient prostatic ducts, enforced GATA3 prevented Akt activation, which correlated with the down-regulation of Pik3cg and Pik3c2a mRNAs, encoding respectively class I and II PI3K subunits. Remarkably, the majority of human prostate tumors similarly show loss of active GATA3 as they progress to the aggressive castrate-resistant stage. In addition, GATA3 expression levels in hormone-sensitive tumors holds predictive value for tumor recurrence. Together, these data establish Gata3 as an important regulator of prostate cancer progression.
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Factor de Transcripción GATA3/metabolismo , Fosfohidrolasa PTEN/deficiencia , Próstata/metabolismo , Neoplasias de la Próstata/metabolismo , Animales , Regulación hacia Abajo , Femenino , Factor de Transcripción GATA3/genética , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Fosfohidrolasa PTEN/antagonistas & inhibidores , Fosfohidrolasa PTEN/genética , Neoplasias de la Próstata/enzimología , Neoplasias de la Próstata/genética , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal , Células Tumorales CultivadasRESUMEN
BACKGROUND: We have previously reported that ErbB family members regulate the signaling pathway leading to Akt and NF-kappaB activation in prostate cancer cells. In this study, the regulation of Akt2 expression in LNCaP, DU145, and PC-3 prostate cancer cell lines was investigated. METHODS: Akt-2 expression was analyzed by western-blotting and Q-PCR in cell lines. We also analyzed the Akt-2 protein expression in a tissue microarray from 64 prostate cancer patients. Akt-2 promoter activity was assessed and analyzed by luciferase assay. RESULTS: A concomitant over-expression of Her-2 and Akt2 expression was observed by western-blotting and quantitative-PCR in prostate cancer cell lines. A significant correlation between Her-2 and Akt2 protein expression was also observed by immunohistochemistry assay on prostate cancer tissues. In LNCaP cells, over-expression of Akt2 protein and mRNA was decreased by Her-2 pharmacologic inhibitors as well as small interfering RNA (siRNA) specific to Her-2. Cloning of the AKT2 promoter in a luciferase reporter plasmid further showed that Akt2 over-expression in cell lines is associated with increased AKT2 promoter activity suggesting that Her-2 modulates a signaling pathway involving AKT2 gene regulation. CONCLUSION: This study reveals a novel mechanism of Akt2 regulation in prostate cancer cells.
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Neoplasias de la Próstata/metabolismo , Proteínas Proto-Oncogénicas c-akt/biosíntesis , Receptor ErbB-2/metabolismo , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Regiones Promotoras Genéticas , Neoplasias de la Próstata/patología , Proteínas Proto-Oncogénicas c-akt/genética , ARN Interferente Pequeño/metabolismo , Receptor ErbB-2/antagonistas & inhibidoresRESUMEN
ErbB3 is a transmembrane tyrosine kinase receptor among the epidermal growth factor receptor (EGFR) family that plays an important role in prostate cancer (PCa) progression. We previously demonstrated that ErbB3 is located in the nucleus of PCa cell lines and PCa tissues. It also was observed that ErbB3 nuclear localization could discriminate between benign and malignant prostate tissues as well as between hormone sensitive and hormone-refractory PCa. Several studies have suggested a role for clathrin-mediated endosomal sorting in the nuclear localization of EGFR and ErbB2 but the mechanisms by which ErbB receptors escape recycling or degradation are not well known. Consequently to determine the role of endocytosis in the nuclear localization of ErbB3, different endocytotic inhibitors and specific si-RNAs were used to discriminate between clathrin-dependent and clathrin-independent pathways. We found that clathrin, caveolin, and membrane domains are not required for endocytosis-mediated nuclear localization of ErbB3 in PCa cells and we provide evidence that amiloride, a macropinocytosis inhibitor, and the ADP-ribosylation factor 6 (Arf6) are implicated in the compartimentalization of ErbB3. In conclusion, evidence for an endocytosis-based mechanism in the nuclear localization of ErbB3 in PCa cells is proposed. These results may help elucidate new therapeutic avenues in PCa that target nuclear ErbB3, which may participate in the progression and aggressivity of the disease.
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Factores de Ribosilacion-ADP/metabolismo , Nucléolo Celular/metabolismo , Pinocitosis/efectos de los fármacos , Neoplasias de la Próstata/metabolismo , Receptor ErbB-3/metabolismo , Factor 6 de Ribosilación del ADP , Animales , Línea Celular Tumoral , Clatrina/metabolismo , Humanos , Masculino , Ratones , Receptor ErbB-3/análisisRESUMEN
OBJECTIVES: In the present study, we investigated whether the pH of IP6 could influence its anti-tumoral activity in vitro. METHODS: PC-3 cells were exposed to IP6 at pH 5, pH 7, and pH 12 and we evaluated the metabolic activity (WST-1 assay), cell proliferation (cell count), cell cycle distribution (FACS), and mitochondrial depolarization (JC-1 staining) in vitro. RESULTS: Our results demonstrated that IP6 at pH 5 and pH 12 were more potent at lowering the metabolic activity of PC-3 cells than IP6 at pH 7. Treatment with IP6 at pH 12 also caused the greatest inhibition in cellular proliferation and accumulation of PC-3 cells in sub-G1. Finally, IP6 at pH 12 lead to a reduction in phospho-AKT and phospho-PDK1 and upregulated phospho-ERK. CONCLUSION: Together, our data strongly suggest that the pH of IP6 effectively modulates its anti-tumoral activity and should be reported in future studies.
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BACKGROUND: Inhibitors of the mammalian target of rapamycin (mTOR) are emerging as promising therapies for metastatic renal cell carcinoma (RCC). Because rational treatment strategies require understanding the activation status of the underlying signaling pathway being targeted at the desired stage of disease, the authors examined the activation status of different components of the mTOR pathway in RCC metastases and matched primary tumors. METHODS: The authors immunostained metastatic RCC samples from 132 patients and a subset of 25 matched primary RCCs with antibodies against phosphatidylinositol 3'-kinase, PTEN, phospho-Akt, phospho-mTOR, and p70S6. PTEN genomic status was assessed by fluorescent in situ hybridization. Marker expression was correlated to clinicopathologic variables and to survival. RESULTS: The mTOR pathway showed widespread activation in RCC metastases of various sites with strong correlation between different components of this signaling cascade (P<.0001), but without significant PTEN genomic deletion. Only cytoplasmic phospho-mTOR showed independent prognostic significance (P = .029) and fidelity between primary RCCs and their matched metastases (P = .004). CONCLUSIONS: Activation of various components of the mTOR signaling pathway in metastatic RCC lesions across various tumor histologies, nuclear grades, and metastatic sites suggests the potential for vertical blockade of multiple steps of this pathway. Patient selection may be improved by mTOR immunostaining of primary RCC.
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Carcinoma de Células Renales/metabolismo , Carcinoma de Células Renales/patología , Eliminación de Gen , Neoplasias Renales/metabolismo , Neoplasias Renales/patología , Fosfohidrolasa PTEN/genética , Serina-Treonina Quinasas TOR/metabolismo , Carcinoma de Células Renales/mortalidad , Femenino , Humanos , Neoplasias Renales/mortalidad , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Pronóstico , Transducción de Señal , Microambiente Tumoral , Regulación hacia ArribaRESUMEN
Translational regulation plays a critical role in the control of cell growth and proliferation. A key player in translational control is eIF4E, the mRNA 5' cap-binding protein. Aberrant expression of eIF4E promotes tumorigenesis and has been implicated in cancer development and progression. The activity of eIF4E is dysregulated in cancer. Regulation of eIF4E is partly achieved through phosphorylation. However, the physiological significance of eIF4E phosphorylation in mammals is not clear. Here, we show that knock-in mice expressing a nonphosphorylatable form of eIF4E are resistant to tumorigenesis in a prostate cancer model. By using a genome-wide analysis of translated mRNAs, we show that the phosphorylation of eIF4E is required for translational up-regulation of several proteins implicated in tumorigenesis. Accordingly, increased phospho-eIF4E levels correlate with disease progression in patients with prostate cancer. Our findings establish eIF4E phosphorylation as a critical event in tumorigenesis. These findings raise the possibility that chemical compounds that prevent the phosphorylation of eIF4E could act as anticancer drugs.
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Factor 4E Eucariótico de Iniciación/metabolismo , Neoplasias/etiología , Neoplasias/patología , Animales , Progresión de la Enfermedad , Factor 4E Eucariótico de Iniciación/genética , Regulación de la Expresión Génica , Técnicas de Sustitución del Gen , Humanos , Masculino , Ratones , Proteínas de Neoplasias/genética , Neoplasias/genética , Fosforilación/fisiología , Regulación hacia ArribaRESUMEN
BACKGROUND: ErbB3-binding protein 1 (Ebp1) is a member of the PA2G4 family of proliferation-regulated proteins that is expressed in multiple malignant and non-malignant cells. ErbB3 and other members of the EGFR family have been implicated in cancer progression, it however remains unknown whether Ebp1 participate in prostate cancer progression in vivo. Therefore, the present study examines Ebp1 expression in cancerous and non-cancerous prostates tissues. Ebp1 expression was also correlated to known Ebp1 regulated proteins (Androgen receptor (AR), Cyclin D1 & ErbB3) and the proliferation marker Ki67. Furthermore we evaluated whether Ebp1 expression correlated with biochemical recurrence (BCR) following radical prostatectomy. METHODS: The expression of Ebp1, AR, Cyclin D1, ErbB3 and Ki67 were evaluated by immunohistochemistry using three separate tissue micro-arrays containing normal prostate tissues, non-cancerous tissue adjacent to the primary tumor, hormone-sensitive and hormone-refractory cancerous tissues. Multivariate COX regression analysis was performed with four clinical parameters in order to correlate Ebp1 expression with PCa progression. RESULTS: The expression of Ebp1 significantly increased with the progression from normal to hormone sensitive and to hormone refractory PCa. Furthermore, we observed strong correlation between Ebp1 expression and the nuclear expression of AR, Cyclin D1 and ErbB3 in both normal adjacent and cancer tissues. The expression of AR, Cyclin D1 and ErbB3 in normal adjacent tissues correlated with PSA relapse, whereas Ebp1 on its own did not significantly predict PSA relapse. Finally, in a multivariate analysis with a base clinical model (Gleason, Pre-op PSA, surgical margins and P-stage) we identified the multi-marker combination of Ebp1+/Cyclin D1- as an independent predictor of PSA relapse with a hazard ratio of 4.79. CONCLUSION: Although not related to disease recurrence, this is the first in vivo study to report that Ebp1 expression correlates with PCa progression.
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OBJECTIVE: To address, by co-assessing cytoplasmic and nuclear androgen receptor (AR) expression in prostate tissues, the contribution of the AR throughout the stages of prostate cancer (PC) and its value as a marker for predicting biochemical recurrence (BCR) after radical prostatectomy (RP). PATIENTS AND METHODS: Archival prostate specimens from patients who were cancer-free (43), with hormone-sensitive prostate cancer (HSPC, 62), and with androgen-independent prostate cancer (AIPC, 30) were used to construct tissue microarrays (total 135). Prostatic intraepithelial neoplasia (PIN) and non-neoplastic tissues (NA) found adjacent to HSPC were also included. Nuclear and cytoplasmic AR expression was scored by two observers using a composite scale, after immunohistochemical detection of the AR. The nuclear/cytoplasmic AR expression ratio was also calculated. Univariate Kaplan-Meier plots, and multivariate Cox and survival-tree analyses, were then used to assess the ability of the AR to predict BCR in the patients with HSPC. RESULTS: There was markedly greater nuclear AR staining intensity in NA than in normal prostate tissues from cancer-free patients. Cytoplasmic AR expression was highest in AIPC and markedly more than in HSPC. The nuclear/cytoplasmic AR expression ratio was highest in NA and PIN. In univariate analyses, a low nuclear AR, low cytoplasmic AR, and a high nuclear/cytoplasmic AR expression ratio were associated with BCR. Although cytoplasmic AR was an independent predictor of BCR in a Cox multivariate model (hazard ratio 2.736, 95% confidence interval 1.228-6.091, P = 0.014), survival-tree analyses suggested a complex relationship between AR expression and clinicopathological features. CONCLUSION: We propose that increased nuclear AR expression might be a precursor to PC and that cytoplasmic AR could contribute to the AIPC phenotype. The predictive ability of the AR might be closely linked to clinicopathological features.
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Biomarcadores de Tumor/análisis , Neoplasias Hormono-Dependientes/química , Próstata/química , Neoplasias de la Próstata/química , Receptores Androgénicos/análisis , Anciano , Anciano de 80 o más Años , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/diagnóstico , Neoplasias Hormono-Dependientes/mortalidad , Neoplasias Hormono-Dependientes/patología , Neoplasias Hormono-Dependientes/cirugía , Pronóstico , Próstata/patología , Prostatectomía/métodos , Neoplasias de la Próstata/mortalidad , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/cirugía , Receptores Androgénicos/metabolismo , Análisis de SupervivenciaRESUMEN
PURPOSE: To assess the expression of proapoptotic NOXA and PUMA in prostate tissues and delineate their association with prostate cancer (PCa) recurrence. EXPERIMENTAL DESIGN: Normal, prostatic intraepithelial neoplasia (PIN), hormone-sensitive (HS) PCa, and hormone-refractory (HR) PCa tissues were used to build tissue microarrays encompassing a total of 135 patients. Two observers assessed the intensity of NOXA and PUMA immunohistochemical staining using a composite color scale. One hundred and eighty recursive partitioning and regression tree (RPART) models were generated to predict biochemical recurrence (BCR) within HS cancer patients using NOXA, PUMA, and clinical parameters. Models were then ranked according to the integrated Brier score (IBS). RESULTS: Increasing NOXA expression was associated with PCa progression, reaching the highest levels in HR PCa. Increased NOXA expression was observed in 68% of HS cancer patients and was predictive of BCR (LR = 8.64; P = 0.003). In contrast, PUMA expression was highest in HS cancer, and although 70% of HS cancer patients exhibited increased PUMA expression, PUMA alone could not predict the onset of BCR. Interestingly, the top-ranking RPART model generated [IBS = 0.107; 95% confidence interval (95% CI), 0.065-0.128] included surgical margin status and NOXA and PUMA expression, although recurrent prognostic classification schemes obtained in the top 10 models favored a survival tree model containing margin status, NOXA expression, and preoperative prostate-specific antigen (PSA) (IBS = 0.114; 95% CI, 0.069-0.142). CONCLUSION: We conclude that NOXA and PUMA expression may be linked to PCa progression and propose further validation of a survival tree model including surgical margin status, NOXA expression, and preoperative PSA for predicting BCR.
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Proteínas Reguladoras de la Apoptosis/biosíntesis , Biomarcadores de Tumor/biosíntesis , Recurrencia Local de Neoplasia/metabolismo , Neoplasia Intraepitelial Prostática/metabolismo , Neoplasias de la Próstata/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/biosíntesis , Proteínas Proto-Oncogénicas/biosíntesis , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Apoptosis/genética , Apoptosis/fisiología , Proteínas Reguladoras de la Apoptosis/genética , Biomarcadores de Tumor/genética , Línea Celular Tumoral , Progresión de la Enfermedad , Humanos , Estimación de Kaplan-Meier , Masculino , Análisis por Micromatrices , Persona de Mediana Edad , Recurrencia Local de Neoplasia/genética , Recurrencia Local de Neoplasia/patología , Neoplasia Intraepitelial Prostática/genética , Neoplasia Intraepitelial Prostática/patología , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/patología , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas c-bcl-2/genéticaRESUMEN
PURPOSE: The ErbB1 and ErbB2 receptors have been implicated in prostate cancer progression, but less is known about the role and biology of other ErbB receptor family members in prostate cancer. The aim of this study was to analyze the expression and localization of ErbB3 in prostate tissues and prostate cancer cell lines. EXPERIMENTAL DESIGN: Immunohistochemistry of ErbB3 was done on prostate cancer tissue sections from 143 patients and on a tissue microarray containing 390 cores of radical prostatectomy-derived specimens representing normal, prostatic intraepithelial neoplasia, and malignant tissues from 81 patients. ErbB3 subcellular localization was studied by Western blot analysis in LNCaP, 22Rv1, PC-3, and DU145 prostate cancer cell lines. RESULTS: Immunohistochemistry analysis of prostate cancer tissues revealed that >90% of prostate cancer tissues displayed cytoplasmic ErbB3 staining. Minimal ErbB3 nuclear staining was observed in normal prostate tissues and benign prostatic hyperplasia tissues; in contrast, ErbB3 was frequently localized in the nucleus of cancerous tissues. This nuclear localization was more frequent (P < 0.001) in hormone-refractory tissues (17 of 17, 100%) compared with hormone-sensitive samples (37 of 92, 40.2%). Additionally, in the tissue microarray, increased nuclear ErbB3 was associated with increasing Gleason grade. Interestingly, Western blot analysis of cytoplasmic and nuclear subcellular fractions showed that ErbB3 nuclear localization was more prevalent in hormone-sensitive prostate cancer cell lines (LNCaP and 22Rv1) compared with hormone-insensitive cell lines (PC-3 and DU145). CONCLUSIONS: ErbB3 nuclear localization discriminates normal from malignant prostate tissues and between tumors from hormone-sensitive versus hormone-refractory prostate cancer. ErbB3 nuclear staining seems to be associated with risk of disease progression. The high frequency of ErbB3 nuclear localization in hormone-refractory tissues indicates that ErbB3 warrants further study to understand its association with prostate cancer disease progression.
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Neoplasias de la Próstata/genética , Receptor ErbB-3/genética , Núcleo Celular/genética , Progresión de la Enfermedad , Regulación Neoplásica de la Expresión Génica , Humanos , Inmunohistoquímica , Masculino , Neoplasias de la Próstata/patología , Receptor ErbB-3/metabolismoRESUMEN
BACKGROUND: Recent research has highlighted the potential role of EGFR and Her-2 in the constitutive activation of NF-kappaB (NF-kappaB) in prostate cancer cells, although the mechanism by which these receptors activate NF-kappaB in these cells remains unclear. METHODS AND RESULTS: Using pharmacological and genetic approaches we show that in PC-3 cells, EGFR and Her-2 are involved in the constitutive activation of NF-kappaB through two different mechanisms. EGFR activates NF-kappaB through the PI3K/Akt pathway that leads to the phosphorylation of IkappaBalpha on serines 32 and 36, thereby promoting the nuclear translocation of the p65 subunit. In contrast, Her-2 activates NF-kappaB through Casein Kinase II (CK-2) activation independently of IkappaBalpha phosphorylation on serines 32 and 36. CONCLUSIONS: Our study not only directly clarifies the signaling pathways involved in NF-kappaB activation in prostate cancer cell lines and but also provides a framework for further studies in the clinical characterization and management of prostate cancer.
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Quinasa de la Caseína II/metabolismo , Receptores ErbB/metabolismo , FN-kappa B/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Neoplasias de la Próstata/metabolismo , Receptor ErbB-2/metabolismo , Western Blotting , Quinasa de la Caseína II/antagonistas & inhibidores , Línea Celular Tumoral , Cromonas/farmacología , Ensayo de Cambio de Movilidad Electroforética , Activación Enzimática , Inhibidores Enzimáticos/farmacología , Humanos , Proteínas I-kappa B/metabolismo , Masculino , Morfolinas/farmacología , Inhibidor NF-kappaB alfa , Inhibidores de las Quinasa Fosfoinosítidos-3 , Fosforilación , Neoplasias de la Próstata/enzimología , Transducción de Señal , Tirfostinos/farmacologíaRESUMEN
BACKGROUND: The mechanism through which NF-kappaB (NF-kappaB) is constitutively activated in prostate cancer cells remains unclear. We investigated whether members of the ErbB family of epidermal growth factor receptors (EGFR) are involved in the constitutive activation of NF-kappaB in prostate cancer cell lines. METHODS AND RESULTS: EGFR, Her-2, and ErbB3 are expressed and constitutively activated in PC-3, DU145, and LNCaP prostate cancer cells lines. Using several pharmacological ErbB inhibitors, we demonstrate that EGFR and Her-2 are involved in the constitutive activation of NF-kappaB in PC-3 cells through two different mechanisms. EGFR activates NF-kappaB through the phosphorylation of IkappaBalpha on serines 32/36 thereby influencing the nuclear translocation of the p65 subunit. In contrast, Her-2 activates NF-kappaB independently of IkappaBalpha phosphorylation on serines 32/36. CONCLUSION: This study directly implicates ErbB receptors in the activation of NF-kappaB in PC-3 prostate cancer cells.