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2.
Int J Mol Sci ; 23(21)2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36362115

RESUMO

Prostate cancer (PCa) is one of the most commonly diagnosed types of malignancy and is the second leading cause of cancer-related death in men in developed countries. Cyclin dependent kinase 2 associate protein 1(CDK2AP1) is an epigenetic and cell cycle regulator gene which has been downregulated in several malignancies, but its involvement in PCa has not yet been investigated in a clinical setting. We assessed the prognostic value of CDK2AP1 expression in a cohort of men diagnosed with PCa (n = 275) treated non-surgically by transurethral resection of the prostate (TURP) and studied the relationship between CDK2AP1 expression to various PCa molecular subtypes (ERG, PTEN, p53 and AR) and evaluated the association with clinical outcome. Further, we used bioinformatic tools to analyze the available TCGA PRAD transcriptomic data to explore the underlying mechanism. Our data confirmed increased expression of CDK2AP1 with higher Gleason Grade Group (GG) and metastatic PCa (p <0.0001). High CDK2AP1 expression was associated with worse overall survival (OS) (HR: 1.62, CI: 1.19−2.21, p = 0.002) and cause-specific survival (CSS) (HR: 2.012, CI 1.29−3.13, p = 0.002) using univariate analysis. When compared to each sub-molecular type. High CDK2AP1/PTEN-loss, abnormal AR or p53 expression showed even worse association to poorer OS and CCS and remained significant when adjusted for GG. Our data indicates that CDK2AP1 directly binds to p53 using the Co-Immunoprecipitation (Co-IP) technique, which was validated using molecular docking tools. This suggests that these two proteins have a significant association through several binding features and correlates with our observed clinical data. In conclusion, our results indicated that the CDK2AP1 overexpression is associate with worse OS and CSS when combined with certain PCa molecular subtypes; interaction between p53 stands out as the most prominent candidate which directly interacts with CDK2AP1.


Assuntos
Neoplasias da Próstata , Ressecção Transuretral da Próstata , Humanos , Masculino , Quinase 2 Dependente de Ciclina/genética , Quinase 2 Dependente de Ciclina/metabolismo , Proteínas Inibidoras de Quinase Dependente de Ciclina/metabolismo , Simulação de Acoplamento Molecular , Neoplasias da Próstata/metabolismo , Proteína Supressora de Tumor p53/genética
3.
Int J Legal Med ; 136(2): 397-404, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34718845

RESUMO

Identification of semen and spermatozoa is crucial in the forensic investigation of alleged sexual assault cases. In cases of alleged sexual assault where there is a long time gap between the incident and sample collection, or in cases of low sperm count, current methods have limitations of specificity, in the case of presumptive tests for semen, or the problem of recording spermatozoa by microscopy if they are few in number. A 3-plex MSRE-PCR (methylation-sensitive restriction enzyme-PCR) assay using a spermatozoa-specific DNA methylated marker to identify spermatozoa has been reported previously by our laboratory. A key advantage over current methods is the increased sensitivity and specificity. A transition from a research tool to operational use requires blind trial testing and inter-laboratory trials. We report on a collaborative exercise where reagents of the 3-plex MSRE-PCR were sent to six participating laboratories. Each laboratory used their own equipment, consumables, and the presumptive reagents conventionally for body fluid (such as acid phosphatase or PSA), DNA extraction, and quantification in practical casework. The reagents and protocol for the 3-plex MSRE-PCR assay and 9 samples were provided by the organizing laboratory. The participating laboratories were requested to fill in the questionnaire after testing. The reported results from all the six participating laboratories were concordant and the expected correct results for the presence of spermatozoa. These outcomes verified the reproducibility and feasibility of the 3-plex MSRE-PCR assay. The results also indicated that the 3-plex MSRE-PCR assay was readily accessible to forensic laboratories for integrating it into current forensic casework processes.


Assuntos
Sêmen , Espermatozoides , Metilação de DNA , Humanos , Masculino , Reação em Cadeia da Polimerase/métodos , Reprodutibilidade dos Testes
4.
Sci Rep ; 11(1): 15370, 2021 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-34321583

RESUMO

Given the unclear preference criteria for regorafenib in treating refractory metastatic colorectal cancer (mCRC), this study aimed to construct an algorithm in selecting right patients for regorafenib. This was a multicenter retrospective cohort study. Patients with pathology confirmed mCRC and administered with regorafenib for > 3 weeks were enrolled. Patients with good response were defined to have progression-free survival (PFS) of ≥ 4 months. The Kaplan-Meier plot was used to analyze survival. A Cox proportional hazards model was used to analyze univariate and multivariate prognostic factors and was visualized using forest plot. A clustering heatmap was used to classify patients according to responses. The decision tree and nomogram were used to construct the approaching algorithm. A total of 613 patients was analyzed. The median PFS and overall survival (OS) were 2.7 and 10.6 months, respectively. The partial response and stable disease rate are 2.4% and 36.4%. The interval between metastasis (M1) and regorafenib, metastatic status (number, liver, and brain), and CEA level were independent prognostics factors of PFS that classifies patients into three groups: good, bad and modest-1/modest-2 group with PFS > = 4 months rates of 51%, 20%, 39% and 30%, respectively. Results were used to develop the decision tree and nomogram for approaching patients indicated with regorafenib. The preference criteria for regorafenib in treating patients with refractory mCRC are small tumor burden (CEA), slow growth (interval between metastasis and regorafenib) and poor/scanty spread (metastatic status: number and sites of metastasis): The 3S rules.TRIAL registration ClinicalTrials.gov Identifier: NCT03829852; Date of first registration (February 11, 2019).


Assuntos
Proliferação de Células/efeitos dos fármacos , Neoplasias Colorretais/tratamento farmacológico , Compostos de Fenilureia/administração & dosagem , Piridinas/administração & dosagem , Carga Tumoral/efeitos dos fármacos , Adulto , Idoso , Neoplasias Colorretais/patologia , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Compostos de Fenilureia/efeitos adversos , Intervalo Livre de Progressão , Modelos de Riscos Proporcionais , Piridinas/efeitos adversos
5.
Clin Colorectal Cancer ; 19(4): e164-e180, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32387305

RESUMO

BACKGROUND: Because more than one neoadjuvant treatment is available for advanced rectal cancer, the aim of this study was to compare the differential clinical and pathologic effects of different combinations of chemoradiation regimens, treatment sequencing, and timing to surgery on patient outcomes. PATIENTS AND METHODS: Between January 2015 and October 2018, 126 newly diagnosed patients with rectal cancer with magnetic resonance imaging-based cT3-4 or N+ rectal disease for curative-intent treatment received 1 of 4 neoadjuvant regimens, followed by immediate surgery or delayed surgery. Whole post-neoadjuvant surgical specimens were assessed by 3-dimensional digital whole-tumor microarray imaging and immunostaining in pathology to analyze the global tumor pathologic regression grades, residual tumor distribution patterns, the extent of lymphovascular permeation, lymph node positivity, and the overall density of lymphocyte infiltration in the tumor microenvironment. These factors were further examined to identify possible correlations with clinical outcomes. RESULTS: Among the 4 neoadjuvant treatment groups, including 2 conventional regimens, we found a significant increase of stromal CD3+ and CD8+ immune infiltrates in the postneoadjuvant tumor microenvironment in the 3 groups with delayed surgery after different chemoradiation regimens compared with the group with immediate surgery after a short course of RT alone. Independent of neoadjuvant chemoradiation regimens, the post-induction high-intermediate-low stromal-infiltrating CD8+ T-cell densities corresponded to tumor regression grades, distant metastasis rates, and disease-free survival and were prognostic factors for the further stratification of patients with American Joint Committee on Cancer stage III rectal cancer into different risk groups after surgery. CONCLUSION: The effectiveness of induction strategies on tumor remission and disease recurrence in advanced rectal cancer was significantly correlated with an enhanced cytotoxic immune response in the tumor microenvironment.


Assuntos
Quimiorradioterapia Adjuvante/estatística & dados numéricos , Terapia Neoadjuvante/estatística & dados numéricos , Recidiva Local de Neoplasia/epidemiologia , Neoplasias Retais/terapia , Microambiente Tumoral/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Quimiorradioterapia Adjuvante/métodos , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante/métodos , Recidiva Local de Neoplasia/prevenção & controle , Estadiamento de Neoplasias , Protectomia , Prognóstico , Neoplasias Retais/diagnóstico , Neoplasias Retais/imunologia , Neoplasias Retais/mortalidade , Reto/diagnóstico por imagem , Reto/imunologia , Reto/cirurgia , Estudos Retrospectivos , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/efeitos da radiação , Adulto Jovem
6.
Micromachines (Basel) ; 10(6)2019 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-31200486

RESUMO

The widely used rigid gas permeable (RGP) contact lenses provide higher oxygen permeability and tear exchange rate than do soft contact lenses. However, their wettability warrants improvement to enhance the wearing comfort. This study used UV laser (wavelength = 355 nm) to modify the surface properties of RGP contact lenses with materials of Boston XO® (Bausch & Lomb Incorporated). Briefly, the mesh pattern was fabricated on the RGP contact lens surface by using the laser and smoothed by using oxygen plasma; the enhanced hydrophilic efficiency was analyzed using contact angle measurement. The experiment results indicated that the contact angle of the lens material decreased by approximately 10°-20° when the pitch of mesh pattern was <50 µm under a 500-mm/s scanning speed. The oxygen plasma enhanced surface wettability with a decreased contact angle (40°). The hydrophilic characteristic of the UV laser and oxygen plasma-treated surface was twice that of oxygen plasma-treated and untreated surfaces. In the future, RGP contact lens edges could be treated with UV laser and oxygen plasma to enhance the tear wettability and wearing comfort.

7.
JAMA Oncol ; 4(9): 1228-1235, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-29978187

RESUMO

Importance: Identification of patients with hereditary renal cell carcinoma (RCC) is important for cancer screening and, in patients with advanced disease, for guiding treatment. The prevalence of cancer-related germline mutations in patients with advanced RCC and the phenotypes associated with some rare mutations are unknown. Objectives: To examine the prevalence of germline mutations in both known RCC predisposition genes and other cancer-associated genes and to identify clinical and pathologic factors associated with germline mutations. Design, Setting, and Participants: In this cohort study conducted from October 1, 2015, to July 31, 2017, 254 of 267 patients with advanced (American Joint Committee on Cancer stage III or IV) RCC who were seen in medical oncology or urology clinics agreed to germline sequencing and disclosure of results under an institutional protocol of matched tumor-germline DNA sequencing. Main Outcomes and Measures: Mutation prevalence and spectrum in patients with advanced RCC were determined. Clinical characteristics were assessed by mutation status. Results: Of the 254 patients (median age [range], 56 [13-79] years; 179 [70.5%] male; 211 [83.1%] non-Hispanic white), germline mutations were identified in 41 (16.1%); 14 (5.5%) had mutations in syndromic RCC-associated genes (7 in FH, 3 in BAP1, and 1 each in VHL, MET, SDHA, and SDHB). The most frequent mutations were CHEK2 (n = 9) and FH (n = 7). Of genes not previously associated with RCC risk, CHEK2 was overrepresented in patients compared with the general population, with an odds ratio of RCC of 3.0 (95% CI, 1.3-5.8; P = .003). Patients with non-clear cell RCC were significantly more likely to have an RCC-associated gene mutation (9 [11.7%] of 74 vs 3 [1.7%] of 177; P = .001), and 8 (10.0%) had a mutation in a gene that could guide therapy. Of patients with mutations in RCC-associated genes, 5 (35.7%) failed to meet current clinical guidelines for genetic testing. Conclusions and Relevance: Of patients with non-clear cell RCC, more than 20% had a germline mutation, of which half had the potential to direct systemic therapy. Current referral criteria for genetic testing did not identify a substantial portion of patients with mutations, supporting the role of a more inclusive sequencing approach.


Assuntos
Carcinoma de Células Renais/genética , Predisposição Genética para Doença/genética , Mutação em Linhagem Germinativa , Neoplasias Renais/genética , Adolescente , Adulto , Idoso , Carcinoma de Células Renais/diagnóstico , Estudos de Coortes , Feminino , Estudos de Associação Genética , Testes Genéticos/métodos , Testes Genéticos/estatística & dados numéricos , Humanos , Neoplasias Renais/diagnóstico , Masculino , Pessoa de Meia-Idade , Prevalência , Adulto Jovem
8.
Pathol Oncol Res ; 23(2): 399-407, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27738792

RESUMO

SPINK1 is proposed as potential prognostic marker in prostate cancer (PCA). However, its relation to PTEN and ERG in localized PCA remains unclear. The study population consisted of two independent cohorts of men treated by radical prostatectomy for localized PCA (discovery n = 218 and validation n = 129). Patterns of association between SPINK1 and each of ERG and PTEN were evaluated by immunohistochemistry and fluorescence in situ hybridization. Associations between SPINK1 expression and various pathologic parameters and clinical outcome were also investigated. SPINK1 was expressed in 15.3 % and 10.9 % of cases in the discovery and validation cohort, respectively. SPINK expression was observed in 5.56 % of high-grade prostatic intraepithelial neoplasia and 1.1 % of adjacent morphologically benign prostatic glands. SPINK1 and ERG expression were almost exclusive, with only 1.0 % of the cases co-expressing both in the same core sample. SPINK1 interfocal and within-core heterogeneity was noted in 29.2 % and 64.6 % of cases, respectively. SPINK1 expression was not significantly associated with PTEN deletion in the two cohorts (p = 0.871 for discovery cohort and p = 0.293 for validation cohort). While SPINK1 expression did occur with hemizygous PTEN deletion, there was a complete absence of SPINK1 expression in PCA showing homozygous PTEN deletion, which was confirmed in the validation cohort (p = 0.02). Despite SPINK1's association with higher Gleason score (>7) (p = 0.02), it was not associated with other pathological parameters or biochemical recurrence post-radical prostatectomy. We documented absolute exclusivity between SPINK1 overexpression and homozygous PTEN deletion in localized PCA. SPINK1 and ERG expressions are exclusive events in PCA. SPINK1 is not of added prognostic value in localized PCA.


Assuntos
Proteínas de Transporte/genética , PTEN Fosfo-Hidrolase/genética , Neoplasias da Próstata/genética , Biomarcadores Tumorais/genética , Deleção de Genes , Humanos , Masculino , Gradação de Tumores/métodos , Prognóstico , Próstata/patologia , Prostatectomia/métodos , Neoplasias da Próstata/patologia , Regulador Transcricional ERG/genética , Inibidor da Tripsina Pancreática de Kazal
9.
Urol Oncol ; 34(5): 235.e1-10, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26725250

RESUMO

BACKGROUND: SPINK1, ERG, and PTEN are proposed prognostic biomarkers in prostate cancer (PCA). However, their relations and patterns of expression in primary and metastatic lymph node (LN) PCAs are not fully explored. METHODS: A tissue microarray of matched primary PCA and LN metastasis was constructed from 36 patients. SPINK1, ERG, and PTEN expression statuses were assessed by immunohistochemistry and correlated with each other. RESULTS: SPINK1 and ERG were expressed in 25% and 42.7% of primary PCA cases, respectively. PTEN loss of any degree was observed in 91.7% of primary PCA cases, with 54.2% showing complete loss. In primary PCA, 12.5% of the cases showed SPINK1+/ERG-phenotype, 16.7% showed SPINK1+/ERG+phenotype, 25.0% showed SPINK1-/ERG+phenotype, and 45.8% showed SPINK1-/ERG-phenotype. All PCAs with expression of either SPINK1 or ERG also exhibited PTEN loss, whereas PCA without PTEN loss (2 cases) expressed neither SPINK1 nor ERG. In primary PCA, evaluation of combined ERG and SPINK1 status, but not SPINK1 individually, was associated with a significant difference in proportion of Gleason patterns (P = 0.013), with the SPINK1+/ERG+and SPINK1-/ERG-phenotypes represented more in Gleason pattern>7 PCAs. In LN metastases, the overall SPINK1 protein expression frequency was significantly lower (6.5% of cases) compared with primary PCA (P = 0.03). Only 16.7% of cases with positive SPINK1 expression in primary PCA maintained expression in LN metastases. The down-regulated SPINK1 expression in LN was primarily because of a reduction in the SPINK1+/ERG+PCA subpopulation to 3.5% of cases (P = 0.16 compared with primary PCA). The frequencies of ERG expression and PTEN loss were relatively stable in primary PCA and LN metastases. CONCLUSION: SPINK1 expression is dynamically regulated with up-regulation in primary sites of nodal metastatic PCA and down-regulation in LN metastases. The increased SPINK1 expression in primary site of nodal metastatic PCA is secondary to an increased frequency of SPINK1+/ERG+tumors. In primary PCAs, the SPINK1+/ERG+phenotype is associated with higher Gleason grade, suggesting that this phenotype may mark a more aggressive PCA subpopulation with higher risk of LN metastases.


Assuntos
Proteínas de Transporte/biossíntese , PTEN Fosfo-Hidrolase/biossíntese , Neoplasias da Próstata/metabolismo , Idoso , Biomarcadores Tumorais/biossíntese , Humanos , Imuno-Histoquímica , Linfonodos/patologia , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Neoplasias da Próstata/patologia , Fatores de Risco , Regulador Transcricional ERG/biossíntese , Inibidor da Tripsina Pancreática de Kazal
10.
Clin Nucl Med ; 40(10): e465-9, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26204213

RESUMO

PURPOSE: FDG PET that has been used is good for diagnosing asymptomatic colorectal cancer (CRC) recurrence in patients with elevated serum carcinoembryonic antigen (CEA) level. However, there is no reference level of CEA rise that would universally suggest the necessity of a PET study. The purpose of this retrospective study was to identify the high-risk group of CRC recurrence through an examination of the dynamics of the CEA level rise as a recurrence indicator. PATIENTS AND METHODS: Between July 2002 and May 2010, 112 patients (59 men, 53 women; age, 18-87 years) had FDG PET for suspicious CRC recurrence indicated by elevated CEA level. We reviewed the PET results and the medical records for recurrence verification and calculated the ratio of increase and the velocity of change in CEA levels for risk stratification. RESULTS: The patient-based sensitivity, specificity, and accuracy of PET are 96.6%, 91.3%, and 95.5%, respectively. The probability of recurrence positively correlated with the CEA level rise and the newly diagnosed disease stage. Carcinoembryonic antigen level greater than 13 ng/mL indicated significantly higher risks of recurrence. In patients with CEA level rise of 13 ng/mL or less, an increase over 3.34 times the individualized baseline also indicated high risks of recurrence. CONCLUSIONS: A posttreatment CEA level rise to greater than 13 ng/mL is suggestive of the optimal use of FDG PET, and so is a mild increase below 13 ng/mL at an increase rate over 3.34.


Assuntos
Biomarcadores Tumorais/sangue , Antígeno Carcinoembrionário/sangue , Neoplasias Colorretais/diagnóstico por imagem , Recidiva Local de Neoplasia/diagnóstico por imagem , Adulto , Idoso , Feminino , Fluordesoxiglucose F18 , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons , Medicina de Precisão , Compostos Radiofarmacêuticos
11.
Cancer Biol Ther ; 15(9): 1120-8, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24972028

RESUMO

ERG and androgen receptor (AR) are known to function cooperatively in prostate cancer (PCa) progression. However, the prognostic value of combined ERG and AR expression and potential pathways are not well characterized. We assessed ERG and AR protein expression by immunohistochemistry in a cohort of 312 men with PCa diagnosed by transurethral resection of the prostate (TURP). Patients were divided into those with no prior hormonal treatment (designated as PCa/AdvPCa) vs. those with castrate-resistant PCa (CRPC) undergoing channel TURP to relieve obstructive symptoms. The expression status was correlated with various clinical-pathological parameters. The Swedish watchful-waiting cohort was used for validation and characterization of potential gene signatures associated with ERG and AR.   Patients with combined ERG-positive/AR high expression profile demonstrated higher rates of PCa-specific mortality (PCSM) compared with patients with ERG-negative/AR low in patients with no prior treatment (n = 90, P = 0.032), but this was attenuated in the overall cohort which included the CRPC subgroup (n = 125, P = 0.096). The prognostic significance to PCSM was validated in the Swedish watchful waiting cohort in univariate (HR: 3.3; 95% CI: 1.9-5.6, P = 4.25E-5) and multivariate analysis (HR: 2; 95% CI: 0.97-4.1, P = 0.057), which included Gleason score. ERG/AR overexpression status characterized 152 genes signatures including WNT, PI3K/AKT and chemokine signaling pathways known to be deregulated in PCa. In conclusion, combined ERG/AR overexpression signifies a class of patients at highest-risk of PCSM with specific key genetic alteration likely responsible for disease progression. The prognostic value of combined ERG/AR overexpression and its associated genes should be further investigated as potential prognostic and therapeutic targets in prostate cancer progression.


Assuntos
Androgênios/deficiência , Neoplasias da Próstata/diagnóstico , Receptores Androgênicos/metabolismo , Transativadores/metabolismo , Idoso , Idoso de 80 Anos ou mais , Quimiocinas/metabolismo , Estudos de Coortes , Terapia Combinada , Progressão da Doença , Intervalo Livre de Doença , Hormônio Liberador de Gonadotropina/agonistas , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Antígeno Prostático Específico/metabolismo , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/mortalidade , Neoplasias da Próstata/terapia , Neoplasias de Próstata Resistentes à Castração/diagnóstico , Neoplasias de Próstata Resistentes à Castração/metabolismo , Neoplasias de Próstata Resistentes à Castração/mortalidade , Neoplasias de Próstata Resistentes à Castração/terapia , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores Androgênicos/genética , Transdução de Sinais , Transativadores/genética , Regulador Transcricional ERG , Ressecção Transuretral da Próstata , Conduta Expectante , Proteínas Wnt/genética , Proteínas Wnt/metabolismo
12.
PLoS One ; 8(8): e73296, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24015300

RESUMO

The Coxsackievirus and Adenovirus Receptor (CAR) is a cell adhesion molecule originally characterized as a virus receptor but subsequently shown to be involved in physiological processes such as neuronal and heart development, epithelial tight junction integrity, and tumour suppression. Proteolysis of cell adhesion molecules and a wide variety of other cell surface proteins serves as a mechanism for protein turnover and, in some cases, cell signaling. Metalloproteases such as A Disintegrin and Metalloprotease (ADAM) family members cleave cell surface receptors to release their substrates' ectodomains, while the presenilin/ɣ-secretase complex mediates regulated intramembrane proteolysis (RIP), releasing intracellular domain fragments from the plasma membrane. In the case of some substrates such as Notch and amyloid precursor protein (APP), the released intracellular domains enter the nucleus to modulate gene expression. We report that CAR ectodomain is constitutively shed from glioma cells and developing neurons, and is also shed when cells are treated with the phorbol ester phorbol 12-myristate 13-acetate (PMA) and the calcium ionophore ionomycin. We identified ADAM10 as a sheddase of CAR using assays involving shRNA knockdown and rescue, overexpression of wild-type ADAM10 and inhibition of ADAM10 activity by addition of its prodomain. In vitro peptide cleavage, mass spectrometry and mutagenesis revealed the amino acids M224 to L227 of CAR as the site of ADAM10-mediated ectodomain cleavage. CAR also undergoes RIP by the presenilin/γ-secretase complex, and the intracellular domain of CAR enters the nucleus. Ectodomain shedding is a prerequisite for RIP of CAR. Thus, CAR belongs to the increasing list of cell surface molecules that undergo ectodomain shedding and that are substrates for ɣ-secretase-mediated RIP.


Assuntos
Secretases da Proteína Precursora do Amiloide/metabolismo , Membrana Celular/metabolismo , Proteína de Membrana Semelhante a Receptor de Coxsackie e Adenovirus/metabolismo , Presenilinas/metabolismo , Proteólise , Proteínas ADAM/genética , Proteínas ADAM/metabolismo , Proteína ADAM10 , Secretases da Proteína Precursora do Amiloide/genética , Animais , Carcinógenos/farmacologia , Linhagem Celular Tumoral , Membrana Celular/genética , Proteína de Membrana Semelhante a Receptor de Coxsackie e Adenovirus/genética , Células HEK293 , Humanos , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Mutagênese Sítio-Dirigida , Neurônios/citologia , Neurônios/metabolismo , Presenilinas/genética , Estrutura Terciária de Proteína , Acetato de Tetradecanoilforbol/farmacologia
13.
FEBS Lett ; 581(14): 2702-8, 2007 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-17531226

RESUMO

The Coxsackie and adenovirus receptor (CAR) is a cell adhesion molecule that is highly expressed in the developing brain. CAR is enriched in growth cone particles (GCP) after subcellular fractionation. In GCP, we identified actin as an interaction partner of the cytoplasmic domain of CAR. In vivo, actin and CAR co-immunoprecipitate and co-localize. In vitro, the binding is direct, with a K(d) of approximately 2.6 microM, and leads to actin bundling. We previously demonstrated that CAR interacts with microtubules. These data suggest a role for CAR in processes requiring dynamic reorganization of the cytoskeleton such as neurite outgrowth and cell migration.


Assuntos
Actinas/metabolismo , Citoesqueleto/metabolismo , Receptores Virais/metabolismo , Sequência de Aminoácidos , Animais , Animais Recém-Nascidos , Células Cultivadas , Proteína de Membrana Semelhante a Receptor de Coxsackie e Adenovirus , Glutationa Transferase/genética , Glutationa Transferase/metabolismo , Cones de Crescimento/metabolismo , Hipocampo/citologia , Hipocampo/metabolismo , Imunoprecipitação , Cinética , Camundongos , Microscopia Eletrônica , Microscopia de Fluorescência , Dados de Sequência Molecular , Neurônios/citologia , Neurônios/metabolismo , Ligação Proteica , Receptores Virais/genética , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Recombinantes de Fusão/ultraestrutura
14.
Langmuir ; 23(3): 1419-26, 2007 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-17241068

RESUMO

We report on the synthesis of highly monodisperse iron nanoparticles, using a chemical reduction method. Iron nanoparticles with an average diameter of 6 nm and a geometric standard deviation of 1.3 were synthesized at a pH of 9.50 from ferric chloride precursor with sodium borohydride as the reducing agent, polyacrylic acid as the dispersing agent, and palladium ions as seeds for iron nanoparticle nucleation. The resulting nanoparticles were ferromagnetic at 5 K and superparamagnetic at 350 K. The dispersing agent polyacrylic acid (PAA) was shown to prevent iron nanoparticles and possibly palladium clusters from aggregating; in the absence of PAA, only aggregated iron nanoparticles were obtained. The addition of palladium ions decreased the diameter of iron nanoparticles presumably by providing sites for heterogeneous nucleation onto palladium clusters. In the absence of palladium ions, the mean diameter of iron nanoparticles was approximately 110 nm and the standard deviation increased to 2.0. The pH of the solution also was found to have a significant effect on the particle diameter, likely by affecting PAA ionization and altering the conformation of the polymer chains. At lower pH (8.75), the PAA is less ionized and its ability to disperse palladium clusters is reduced, so the number of palladium seeds decreases. Therefore, the resulting iron nanoparticles were larger, 59 nm in diameter, versus 6 nm for nanoparticles formed at a pH of 9.50.

15.
J Biol Chem ; 282(10): 7512-21, 2007 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-17210569

RESUMO

The Coxsackie and adenovirus receptor (CAR), a cell adhesion molecule of the immunoglobulin superfamily, inhibits cell growth of a variety of tumors. The cytoplasmic domain of CAR has been implicated in decreased invasion and intracerebral growth of human U87 glioma cells. Using affinity binding, we identified tubulin as an interaction partner for the cytoplasmic domain of CAR. The interaction was specific; CAR and tubulin co-immunoprecipitated in cells expressing endogenous CAR and partially co-localized in situ. The binding of CAR to tubulin heterodimers and to microtubules was direct, with dissociation constants of approximately 1 mum for tubulin and approximately 32 nm for in vitro assembled microtubules. Whereas CAR-expressing U87 glioma cells had decreased migration in a chemotactic assay in Boyden chambers as compared with control cells, an effect that depended on the presence of the cytoplasmic domain of CAR, the difference was abrogated at low, non-cytotoxic doses of the taxane paclitaxel, a microtubule-stabilizing agent. These results indicate that CAR may affect cell migration through its interaction with microtubules.


Assuntos
Microtúbulos/metabolismo , Receptores Virais/fisiologia , Sequência de Aminoácidos , Linhagem Celular Tumoral , Movimento Celular , Proteína de Membrana Semelhante a Receptor de Coxsackie e Adenovirus , Dimerização , Glioma/patologia , Humanos , Dados de Sequência Molecular , Paclitaxel/farmacologia , Estrutura Terciária de Proteína , Receptores Virais/química , Tubulina (Proteína)/metabolismo
16.
Int J Cancer ; 113(5): 738-45, 2005 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-15499626

RESUMO

Expression of the coxsackie and adenovirus receptor (CAR) is downregulated in malignant glioma cell lines and is barely detectable in high-grade primary astrocytoma (glioblastoma multiforme). We determined the effect of forced CAR expression on the invasion and growth of the human glioma cell line U87-MG, which does not express any CAR. Although retrovirally mediated expression of full-length CAR in U87-MG cells did not affect monolayer growth in vitro, it did reduce glioma cell invasion in a 3-dimensional spheroid model. Furthermore, in xenograft experiments, intracerebral implantation of glioma cells expressing full-length CAR resulted in tumors with a significantly reduced volume compared to tumors generated by control vector-transduced U87-MG cells. In contrast, U87-MG cells expressing transmembrane CAR with a deletion of the entire cytoplasmic domain (except for the first 2 intracellular juxtamembrane cysteine amino acids) had rates of invasion and tumor growth that were similar to those of the control cells. This difference in behavior between the 2 forms of CAR was not due to improper cell surface localization of the cytoplasmically deleted CAR as determined by comparable immunostaining of unpermeabilized cells, equivalent adenoviral transduction of the cells and similar extent of fractionation into lipid-rich domains. Taken together, these results suggest that the decrease or loss of CAR expression in malignant glioma may confer a selective advantage in growth and invasion to these tumors.


Assuntos
Neoplasias Encefálicas/patologia , Proliferação de Células , Glioma/patologia , Receptores Virais/fisiologia , Animais , Neoplasias Encefálicas/metabolismo , Proteína de Membrana Semelhante a Receptor de Coxsackie e Adenovirus , Regulação para Baixo/genética , Vetores Genéticos , Glioma/metabolismo , Humanos , Camundongos , Camundongos Nus , Invasividade Neoplásica , Estrutura Terciária de Proteína , Transporte Proteico , Retroviridae/genética , Transfecção , Transplante Heterólogo , Células Tumorais Cultivadas
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