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1.
Oncology ; : 1-16, 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-39134012

RESUMEN

INTRODUCTION: Breast cancer comprises the leading cause of cancer-related death in women. MicroRNAs (miRNAs) have emerged as important factors with concern to carcinogenesis and have potential for use as biomarkers. METHODS: This study provides a comprehensive evaluation of the microRNA expression in invasive breast carcinoma of no special type tissues compared with benign tissues via large-scale screening and the candidate-specific validation of 15 miRNAs and U6 snRNA applying qPCR and the examination of clinicopathological data. RESULTS: Of the six downregulated miRNAs, let-7c was identified as the most promising miRNA biomarker and its lower expression was linked with Ki-67 positivity, luminal B versus luminal A samples, multifocality, lymph node metastasis, and inferior PFS. Of the 9 upregulated sncRNAs, the data on U6 snRNA, miR-493 and miR-454 highlighted their potential oncogenic functions. An elevated U6 snRNA expression was associated with the tumor grade, Ki-67 positivity, luminal B versus A samples, lymph node metastasis, and worsened PFS (and OS) outcomes. An elevated miR-454 expression was detected in higher grades, Ki-67 positive and luminal B versus A samples. Higher miR-493 levels were noted for the tumor stage (and grade) and worse patient outcomes (PFS, OS). The data also suggested that miR-451a and miR-328 may have tumor suppressor roles, and miR-182 and miR-200c pro-oncogenic functions, while the remaining sncRNAs did not evince any significant associations. CONCLUSION: We showed particular microRNAs and U6 snRNA as differentially expressed between tumors and benign tissues and associated with clinicopathological parameters, thus potentially corresponding with important roles in breast carcinogenesis. Their importance should be further investigated and evaluated in follow-up studies to reveal their potential in clinical practice.

2.
Oncology ; 2024 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-38408442

RESUMEN

Introduction Breast cancer is the most common cancer and the leading cause of cancer death in women. Recent research indicates that human endogenous retroviruses (HERVs) may be linked to carcinogenesis, but the data remain controversial. Methods HERVs´ expression was evaluated to show the differences between breast cancer and control samples, and their associations with clinicopathological parameters. Gene expression of 12 HERVs, i.e. ERVE-4, ERVW-1, ERVFRD-1, ERVV-1, ERV3-1, ERVH48-1, ERVMER34-1, ERVK7, ERVK13-1, ERVK11-1, ERVK3-1 and HCP5 was analyzed by qPCR and/or TCGA datasets for breast cancer. Results ERV3-1, ERVFRD-1, ERVH48-1 and ERVW-1 provided data to support their tumor suppressor roles in breast cancer. ERV3-1 evinced the best performing diagnostic data based on qPCR, i.e. AUC: 0.819 (p <0.0001), sensitivity of 72.41%, and specificity of 89.66%. Lower levels of ERV3-1 were noted in advanced stage and higher grades, and significant negative association was found in relation to Ki-67 levels. Oncogenic roles may be inferred for ERVK13-1, ERVV-1, and ERVMER34-1. Data for ERVK-7, ERVE-4, ERVK11-1 and HCP5 remain inconclusive. Conclusion Differential HERVs expression may be applicable to evaluate novel biomarkers for breast cancer. However, more research is needed to reveal their real clinical impact, the biological roles and regulatory mechanisms in breast carcinogenesis.

3.
Cancer Biomark ; 40(1): 61-78, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38277283

RESUMEN

BACKGROUND: Breast cancer is the most commonly occurring cancer worldwide and is the main cause of death from cancer in women. Novel biomarkers are highly warranted for this disease. OBJECTIVE: Evaluation of novel long non-coding RNAs biomarkers for breast cancer. METHODS: The study comprised the analysis of the expression of 71 candidate lncRNAs via screening, six of which (four underexpressed, two overexpressed) were validated and analyzed by qPCR in tumor tissues associated with NST breast carcinomas, compared with the benign samples and with respect to their clinicopathological characteristics. RESULTS: The results indicated the tumor suppressor roles of PTENP1, GNG12-AS1, MEG3 and MAGI2-AS3. Low levels of both PTENP1 and GNG12-AS1 were associated with worsened progression-free and overall survival rates. The reduced expression of GNG12-AS1 was linked to the advanced stage. A higher grade was associated with the lower expression of PTENP1, GNG12-AS1 and MAGI2-AS3. Reduced levels of both MEG3 and PTENP1 were linked to Ki-67 positivity. The NRSN2-AS1 and UCA1 lncRNAs were overexpressed; higher levels of UCA1 were associated with multifocality. CONCLUSIONS: The results suggest that the investigated lncRNAs may play important roles in breast cancer and comprise a potential factor that should be further evaluated in clinical studies.


Asunto(s)
Biomarcadores de Tumor , Neoplasias de la Mama , ARN Largo no Codificante , Humanos , ARN Largo no Codificante/genética , Femenino , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/mortalidad , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Persona de Mediana Edad , Regulación Neoplásica de la Expresión Génica , Adulto , Pronóstico , Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Guanilato-Quinasas/genética , Guanilato-Quinasas/metabolismo , Anciano , Clasificación del Tumor , Genes Supresores de Tumor
4.
Mol Biol Rep ; 49(3): 1955-1971, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34993725

RESUMEN

BACKGROUND: Breast cancer is a leading cause of cancer-related death in women. Most cases are invasive ductal carcinomas of no special type (NST breast carcinomas). METHODS AND RESULTS: In this prospective, multicentric biomarker discovery study, we analyzed the expression of small non-coding RNAs (mainly microRNAs) in plasma by qPCR and evaluated their association with NST breast cancer. Large-scale expression profiling and subsequent validations have been performed in patient and control groups and compared with clinicopathological data. Small nuclear U6 snRNA, miR-548b-5p and miR-451a have been identified as candidate biomarkers. U6 snRNA was remarkably overexpressed in all the validations, miR-548b-5p levels were generally elevated and miR-451a expression was mostly downregulated in breast cancer groups. Combined U6 snRNA/miR-548b-5p signature demonstrated the best diagnostic performance based on the ROC curve analysis with AUC of 0.813, sensitivity 73.1% and specificity 82.6%. There was a trend towards increased expression of both miR-548b-5p and U6 snRNA in more advanced stages. Further, increased miR-548b-5p levels have been partially associated with higher grades, multifocality, Ki-67 positivity, and luminal B rather than luminal A samples. On the other hand, an association has been observed between high miR-451a expression and progesterone receptor positivity, lower grade, unifocal samples, Ki-67-negativity, luminal A rather than luminal B samples as well as improved progression-free survival and overall survival. CONCLUSIONS: Our results indicated that U6 snRNA and miR-548b-5p may have pro-oncogenic functions, while miR-451a may act as tumor suppressor in breast cancer.


Asunto(s)
Neoplasias de la Mama , MicroARNs , Biomarcadores , Biomarcadores de Tumor/genética , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Femenino , Regulación Neoplásica de la Expresión Génica/genética , Humanos , MicroARNs/metabolismo , Pronóstico , Estudios Prospectivos , ARN Nuclear Pequeño
5.
Cancer Biomark ; 33(1): 1-16, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34511487

RESUMEN

Ovarian cancer comprises the most lethal gynecologic malignancy and is accompanied by the high potential for the incidence of metastasis, recurrence and chemotherapy resistance, often associated with a formation of ascitic fluid. The differentially expressed ascites-derived microRNAs may be linked to ovarian carcinogenesis. The article focuses on a number of miRNAs that share a common expression pattern as determined by independent studies using ascites samples and with regard to their functions and outcomes in experimental and clinical investigations.Let-7b and miR-143 have featured as tumor suppressors in ovarian cancer, which is in line with data on other types of cancer. Although two miRNAs, i.e. miR-26a-5p and miR-145-5p, act principally as tumor suppressor miRNAs, they occasionally exhibit oncogenic roles. The performance of miR-95-3p, upregulated in ascites, is open to debate given the current lack of supportive data on ovarian cancer; however, data on other cancers indicates its probable oncogenic role. Different findings have been reported for miR-182-5p and miR-200c-3p; in addition to their presumed oncogenic roles, contrasting findings have indicated their ambivalent functions. Further research is required for the identification and evaluation of the potential of specific miRNAs in the diagnosis, prediction, treatment and outcomes of ovarian cancer patients.


Asunto(s)
MicroARNs , Neoplasias Ováricas , Ascitis/genética , Carcinogénesis/genética , Femenino , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Genes Supresores de Tumor , Humanos , MicroARNs/genética , MicroARNs/metabolismo , Neoplasias Ováricas/patología
7.
Methods Mol Biol ; 1580: 99-106, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28439829

RESUMEN

Cell-free microRNAs (miRNAs) have become one of the novel promising diagnostic and prognostic biomarkers for various diseases recently. Blood serum and plasma along with urine are the most common sources of clinically well, almost noninvasively available samples containing various types of miRNAs. Here, we present a protocol for a small-scale study investigating expression of several candidate miRNAs. Small-scale experiments may be worth investigating in cases where no information is available on miRNAs expression in particular diseases, for validation of previously published miRNAs with promising diagnostic potential, particularly in situations where follow-up study is aimed at validating miRNAs coming from array or NGS experiments, or where funding for these large-scale experiments is not available.Using urine miRNAs expression as the novel diagnostic tools is challenging and currently this approach is still in its infancy. Therefore, various methods may result in different conclusions depending on clinical sample sets and differences among methods used for the miRNAs isolation and quantitation. In this protocol, we present the method evaluated in the study focused on cell-free urinary miRNAs in ovarian and endometrial cancers. We recommend using stabilization tubes for the urine collection, as this step may be necessary to stop activity of RNases. Further, routine real-time PCR methods are described. We demonstrate that assessment of urinary miRNAs expression may reveal as a feasible method to explore the potential for finding novel diagnostic and prognostic markers.


Asunto(s)
MicroARN Circulante/orina , Neoplasias Endometriales/orina , Perfilación de la Expresión Génica/métodos , Neoplasias Ováricas/orina , MicroARN Circulante/genética , MicroARN Circulante/aislamiento & purificación , Neoplasias Endometriales/genética , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias Ováricas/genética , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Urinálisis/métodos
8.
Neuro Endocrinol Lett ; 37(4): 289-294, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27857045

RESUMEN

OBJECTIVES: ADHD is one of the most significant diagnostic units in child and adolescent psychiatry. The occurrence in children is 5-6% and 50-80% continued to adult age. The presence of individual genes (polymorphism) on particular symptoms and processes in ADHD are not known. It is estimated that ADHD symptoms are up to 80% to genetic. The higher density of resultant DAT 1 protein was observed in ADHD patients in comparison with controls. The question was if DAT 1 10/10 predicted bad prognoses in long term therapy. METHODS: We compared 30 ADHD DAT 1 10/10 adolescents treated for 5-6 years. Patients with 30 control adolescents. They were the same age of probands and controls. All these subjects were examined by child psychiatry scales (Conners, Achenbach…). Biological changes were tested by MRI specific CNS volumometry. RESULTS: We didn't confirm bad prognoses in long term therapy with methylphenidate or atomoxetine in ADHD children DAT 1 10/10 in long term therapy. In MRI specific CNS volumometry were not identify any differences in controls and ADHD probands. Gray matter thickness was significantly higher in prefrontal and occipital areas in patients compared to control in prefrontal and occipital areas with cluster-wise p-value<0.05. By this method were not identify any cerebrum damage in long term therapy by methylphenidate and atomoxetine.


Asunto(s)
Inhibidores de Captación Adrenérgica/uso terapéutico , Clorhidrato de Atomoxetina/uso terapéutico , Trastorno por Déficit de Atención con Hiperactividad/tratamiento farmacológico , Encéfalo/diagnóstico por imagen , Estimulantes del Sistema Nervioso Central/uso terapéutico , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática/genética , Metilfenidato/uso terapéutico , Adolescente , Trastorno por Déficit de Atención con Hiperactividad/diagnóstico por imagen , Trastorno por Déficit de Atención con Hiperactividad/genética , Encéfalo/patología , Femenino , Sustancia Gris/diagnóstico por imagen , Sustancia Gris/patología , Humanos , Imagen por Resonancia Magnética , Masculino , Lóbulo Occipital/diagnóstico por imagen , Lóbulo Occipital/patología , Tamaño de los Órganos , Polimorfismo Genético , Corteza Prefrontal/diagnóstico por imagen , Corteza Prefrontal/patología , Pronóstico
9.
Mol Clin Oncol ; 5(1): 161-164, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27330791

RESUMEN

The present study reports a case of a 44-year-old female patient with a large frontal lobe tumor who underwent surgery using a modern navigation system SonoWand that combines the advantages of a non-frame navigation system with intraoperative real-time ultrasound imaging. The right frontal lobe tumor consisted of two morphologically different sections. A diffuse astrocytoma grade II and a glioblastoma grade IV were identified. These tumors were relatively substantially separated. A 17 p deletion, including TP53, was detected in a diffuse astrocytoma but not in a glioblastoma. EGFR and MDM2 amplifications were detected only in a glioblastoma. Detection of these amplifications is typical for primary glioblastomas. These findings support our assumption of two independent tumors. The KRAS, BRAF and EGFR gene mutations were also detected in a glioblastoma. Such an accumulation of molecular mutations is rare in one tumor. Following oncological treatment the patient was cared for in the oncological center and survived for 15 months after the surgery without any signs of a disease. This is an unusual case, and to the best of our knowledge, is not frequently published in literature.

10.
Neuro Endocrinol Lett ; 37(1): 29-32, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26994382

RESUMEN

We discussed the cross section studies and the meta-analysis of published data in children and adolescents with ADHD (both drug naive and receiving stimulant medications), in comparison with healthy children and adolescents of the same age. In children and adolescents with ADHD the deceleration of the maturation dynamics of discrete CNS structures is found, volume reduction and decreased grey matter in prefrontal and occipital regions, which is accompanied by reverse asymmetry of the basal ganglia volume (putamen, nucleus caudate). The above mentioned developmental characteristics are valid only for the ADHD children, who have not been treated by stimulant medications. The stimulant treatment eliminates the mentioned changes into various extend. These developmental changes of CNS structures volume are missing in girls.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/tratamiento farmacológico , Trastorno por Déficit de Atención con Hiperactividad/patología , Ganglios Basales/anomalías , Encéfalo/anomalías , Estimulantes del Sistema Nervioso Central/uso terapéutico , Adolescente , Ganglios Basales/efectos de los fármacos , Ganglios Basales/patología , Encéfalo/efectos de los fármacos , Encéfalo/patología , Niño , Estudios Transversales , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Tamaño de los Órganos/efectos de los fármacos
11.
Pathol Oncol Res ; 21(4): 1027-35, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25827090

RESUMEN

Among gynaecological cancers, epithelial ovarian cancers are the most deadly cancers while endometrial cancers are the most common diseases. Efforts to establish relevant novel diagnostic, screening and prognostic markers are aimed to help reduce the high level of mortality, chemoresistance and recurrence, particularly in ovarian cancer. MicroRNAs, the class of post-transcriptional regulators, have emerged as the promising diagnostic and prognostic markers associated with various diseased states recently. Urine has been shown as the source of microRNAs several years ago; however, there has been lack of information on urine microRNA expression in ovarian and endometrial cancers till now. In this pilot study, we examined the expression of candidate cell-free urine microRNAs in ovarian cancer and endometrial cancer patients using quantitative real-time PCR. We compared the expression between pre- and post-surgery ovarian cancer samples, and between patients with ovarian and endometrial cancers and healthy controls, within three types of experiments. These experiments evaluated three different isolation methods of urine RNA, representing two supernatant and one exosome fractions of extracellular microRNA. In ovarian cancer, we found miR-92a significantly up-regulated, and miR-106b significantly down-regulated in comparison with control samples. In endometrial cancer, only miR-106b was found down-regulated significantly compared to control samples. Using exosome RNA, no significant de-regulations in microRNAs expression could be found in either of the cancers investigated. We propose that more research should now focus on confirming the diagnostic potential of urine microRNAs in gynaecological cancers using more clinical samples and large-scale expression profiling methods.


Asunto(s)
Neoplasias Endometriales/diagnóstico , Neoplasias Endometriales/orina , MicroARNs/genética , MicroARNs/orina , Neoplasias Ováricas/diagnóstico , Neoplasias Ováricas/orina , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/orina , Estudios de Casos y Controles , Regulación hacia Abajo/genética , Neoplasias Endometriales/genética , Exosomas/genética , Femenino , Humanos , Persona de Mediana Edad , Neoplasias Ováricas/genética , Proyectos Piloto , Pronóstico , Regulación hacia Arriba/genética
12.
Reprod Biomed Online ; 29(2): 245-50, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24928354

RESUMEN

Heterochromatin variants are commonly found during cytogenetic examinations, and chromosomes 1, 9, 16 and Y are commonly involved in these variations. These variants are believed to be clinically insignificant variations in human karyotypes. Nevertheless, reproductive failure has been frequently discussed as possibly being associated with these variants. Various authors have reported a significantly elevated incidence of these variants in individuals with idiopathic reproductive failure compared with individuals with no such history. This study compared the incidence of heterochromatin variants in individuals with idiopathic reproductive failure (n=1036) with that of a control group of healthy fetuses (n=995) indicated for prenatal karyotype examination solely based on the advanced ages of their mothers. The heterochromatin variants occurred more frequently in the reproductive failure group than in the controls (P=0.006). Regarding individual chromosomes, chromosome 9 variants were most frequently found in the study and control groups, and they also occurred more frequently in the reproductive failure group. The most significant difference between the study and control groups was found for the 9qh+ variant (P=0.026), and although the results are statistically significant, the cause of this phenomenon remains unknown.


Asunto(s)
Heterocromatina/genética , Infertilidad Femenina/genética , Infertilidad Masculina/genética , Cariotipificación , Femenino , Humanos , Masculino , Estudios Retrospectivos
13.
BMC Med Genet ; 15: 41, 2014 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-24694054

RESUMEN

BACKGROUND: Autosomal dominant polycystic kidney disease (ADPKD) is the most common hereditary renal disorder caused by mutation in either one of two genes, PKD1 and PKD2. High structural and sequence complexity of PKD genes makes the mutational diagnostics of ADPKD challenging. The present study is the first detailed analysis of both PKD genes in a cohort of Czech patients with ADPKD using High Resolution Melting analysis (HRM) and Multiplex Ligation-dependent Probe Amplification (MLPA). METHODS: The mutational analysis of PKD genes was performed in a set of 56 unrelated patients. For mutational screening of the PKD1 gene, the long-range PCR (LR-PCR) strategy followed by nested PCR was used. Resulting PCR fragments were analyzed by HRM; the positive cases were reanalyzed and confirmed by direct sequencing. Negative samples were further examined for sequence changes in the PKD2 gene by the method of HRM and for large rearrangements of both PKD1 and PKD2 genes by MLPA. RESULTS: Screening of the PKD1 gene revealed 36 different likely pathogenic germline sequence changes in 37 unrelated families/individuals. Twenty-five of these sequence changes were described for the first time. Moreover, a novel large deletion was found within the PKD1 gene in one patient. Via the mutational analysis of the PKD2 gene, two additional likely pathogenic mutations were detected. CONCLUSIONS: Probable pathogenic mutation was detected in 71% of screened patients. Determination of PKD mutations and their type and localization within corresponding genes could help to assess clinical prognosis of ADPKD patients and has major benefit for prenatal and/or presymptomatic or preimplantational diagnostics in affected families as well.


Asunto(s)
Mutación/genética , Riñón Poliquístico Autosómico Dominante/genética , Canales Catiónicos TRPP/genética , Estudios de Cohortes , República Checa , Femenino , Ligamiento Genético , Pruebas Genéticas/métodos , Humanos , Masculino , Reacción en Cadena de la Polimerasa Multiplex , Reacción en Cadena de la Polimerasa , Análisis de Secuencia de ADN , Temperatura de Transición
14.
BMC Nephrol ; 14: 59, 2013 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-23496908

RESUMEN

BACKGROUND: Autosomal dominant polycystic kidney disease (ADPKD) is the most common form of inherited kidney disease that results in renal failure. ADPKD is a systemic disorder with cysts and connective tissue abnormalities involving many organs. ADPKD caused by mutations in PKD1 gene is significantly more severe than the cases caused by PKD2 gene mutations. The large intra-familial variability of ADPKD highlights a role for genetic background. CASE PRESENTATION: Here we report a case of ADPKD family initially appearing unlinked to the PKD1 or PKD2 loci and the influence of mosaicism and hypomorphic allele on the variability of the clinical course of the disease. A grandmother with the PKD1 gene mutation in mosaicism (p.Val1105ArgfsX4) and with mild clinical course of ADPKD (end stage renal failure at the age of 77) seemed to have ADPKD because of PKD2 gene mutation. On the other hand, her grandson had a severe clinical course (end stage renal disease at the age of 45) in spite of the early treatment of mild hypertension. There was found by mutational analysis of PKD genes that the severe clinical course was caused by PKD1 gene frameshifting mutation inherited from his father and mildly affected grandmother in combination with inherited hypomorphic PKD1 allele with described missense mutation (p.Thr2250Met) from his clinically healthy mother. The sister with two cysts and with PKD1 hypomorphic allele became the kidney donor to her severely affected brother. CONCLUSION: We present the first case of ADPKD with the influence of mosaicism and hypomorphic allele of the PKD1 gene on clinical course of ADPKD in one family. Moreover, this report illustrates the role of molecular genetic testing in assessing young related kidney donors for patients with ADPKD.


Asunto(s)
Alelos , Mutación del Sistema de Lectura/genética , Mosaicismo , Riñón Poliquístico Autosómico Dominante/genética , Canales Catiónicos TRPP/genética , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Linaje , Riñón Poliquístico Autosómico Dominante/diagnóstico
15.
Fam Cancer ; 12(1): 35-42, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22987206

RESUMEN

Familial adenomatous polyposis (FAP) is an autosomal dominant syndrome with almost 100 % risk of colorectal cancer. The typical FAP is characterized by hundreds to thousands of colorectal adenomatous polyps and by extracolonic manifestations, later onset and lower number of polyps in colon is characteristic of an attenuated form (AFAP). We analyzed the APC gene for germline mutations in 90 FAP/AFAP patients. Mutation screening was performed using Denaturing Gradient Gel Electrophoresis. DNA fragments showing an aberrant electrophoretic banding pattern were sequenced. APC-mutation-negative probands were screened for large deletions of the APC gene using multiplex ligation dependent probe amplification. Analysis of mRNA variants followed in probands with possible splicing mutation by PCR amplification of target site flanking exons and sequencing the normal and aberrant products. We identified 30 germline variants among 36 unrelated probands including large deletions. Eleven APC variants detected last two years have not been reported yet. At all, fifteen of them are expected to cause errors in mRNA splicing. Analysis of mRNA in ten of these patients revealed exon skipping in seven cases, exonisation of intron in one of these as well, change of the amount of alternatively spliced product in one case, and no effect was found in three cases. In two of the patients, the biopsy of colon mucosa and polyp enabled us to examine the effect of the mutation on splicing pattern in colon cells directly. The comparison of alternative and standard transcript amount showed similar transcription pattern of exon 14 in control colon mucosa tissue (9 samples) as in 51 blood control samples.


Asunto(s)
Poliposis Adenomatosa del Colon/genética , Empalme Alternativo , Neoplasias Colorrectales/genética , Genes APC , República Checa , Femenino , Predisposición Genética a la Enfermedad , Humanos , Masculino , Mutación
16.
J Exp Bot ; 63(10): 3815-27, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22438304

RESUMEN

The molecular basis of cellular auxin transport is still not fully understood. Although a number of carriers have been identified and proved to be involved in auxin transport, their regulation and possible activity of as yet unknown transporters remain unclear. Nevertheless, using single-cell-based systems it is possible to track the course of auxin accumulation inside cells and to specify and quantify some auxin transport parameters. The synthetic auxins 2,4-dichlorophenoxyacetic acid (2,4-D) and naphthalene-1-acetic acid (NAA) are generally considered to be suitable tools for auxin transport studies because they are transported specifically via either auxin influx or efflux carriers, respectively. Our results indicate that NAA can be metabolized rapidly in tobacco BY-2 cells. The predominant metabolite has been identified as NAA glucosyl ester and it is shown that all NAA metabolites were retained inside the cells. This implies that the transport efficiency of auxin efflux transporters is higher than previously assumed. By contrast, the metabolism of 2,4-D remained fairly weak. Moreover, using data on the accumulation of 2,4-D measured in the presence of auxin transport inhibitors, it is shown that 2,4-D is also transported by efflux carriers. These results suggest that 2,4-D is a promising tool for determining both auxin influx and efflux activities. Based on the accumulation data, a mathematical model of 2,4-D transport at a single-cell level is proposed. Optimization of the model provides estimates of crucial transport parameters and, together with its validation by successfully predicting the course of 2,4-D accumulation, it confirms the consistency of the present concept of cellular auxin transport.


Asunto(s)
Ácidos Indolacéticos/química , Ácidos Indolacéticos/metabolismo , Nicotiana/química , Nicotiana/metabolismo , Reguladores del Crecimiento de las Plantas/química , Reguladores del Crecimiento de las Plantas/metabolismo , Ácido 2,4-Diclorofenoxiacético/química , Ácido 2,4-Diclorofenoxiacético/metabolismo , Transporte Biológico , Células Cultivadas , Modelos Teóricos , Naftalenos/química , Naftalenos/metabolismo , Nicotiana/citología
19.
BMC Med Genet ; 10: 78, 2009 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-19686598

RESUMEN

BACKGROUND: Autosomal dominant polycystic kidney disease (ADPKD) is the most common hereditary renal disease. The disease is caused by mutations of the PKD1 (affecting roughly 85% of ADPKD patients) and PKD2 (affecting roughly 14% of ADPKD patients) genes, although in several ADPKD families, the PKD1 and/or PKD2 linkage was not found. Mutation analysis of the PKD1 gene is complicated by the presence of highly homologous genomic duplications of the first two thirds of the gene. METHODS: The direct detection of mutations in the non-duplicated region of the PKD1 gene was performed in 90 unrelated individuals, consisting of 58 patients with end-stage renal failure (manifesting before their 50th year of life) and 32 individuals from families where the disease was clearly linked to the PKD1 gene. Mutation screening was performed using denaturing gradient gel electrophoresis (DGGE). DNA fragments showing an aberrant electrophoretic banding pattern were sequenced. RESULTS: In the non-duplicated region of the PKD1 gene, 19 different likely pathogenic germline sequence changes were identified in 19 unrelated families/individuals. Fifteen likely pathogenic sequence changes are unique for the Czech population. The following probable mutations were identified: 9 nonsense mutations, 6 likely pathogenic missense mutations, 2 frameshifting mutations, one in-frame deletion and probable splice site mutation. In the non-duplicated region of the PKD1 gene, 16 different polymorphisms or unclassified variants were detected. CONCLUSION: Twenty probable mutations of the PKD1 gene in 90 Czech individuals (fifteen new probable mutations) were detected. The establishment of localization and the type of causal mutations and their genotype phenotype correlation in ADPKD families will improve DNA diagnosis and could help in the assessment of the clinical prognosis of ADPKD patients.


Asunto(s)
Mutación , Riñón Poliquístico Autosómico Dominante/genética , Canales Catiónicos TRPP/genética , Adulto , República Checa , Análisis Mutacional de ADN , Femenino , Duplicación de Gen , Mutación de Línea Germinal , Humanos , Masculino , Persona de Mediana Edad , Mutación Missense , Polimorfismo Genético , Análisis de Secuencia de ADN
20.
BMC Med Genet ; 8: 16, 2007 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-17411426

RESUMEN

BACKGROUND: Germline mutations in the adenomatous polyposis gene (APC) result in familial adenomatous polyposis (FAP). FAP is an autosomal dominantly inherited disorder predisposing to colorectal cancer. Typical FAP is characterized by hundreds to thousands of colorectal adenomatous polyps and by several extracolonic manifestations. An attenuated form of polyposis (AFAP) is characterized by less than 100 adenomas and later onset of the disease. METHODS: Here, we analyzed the APC gene for germline mutations in 59 Czech and 15 Slovak FAP patients. In addition, 50 apparently APC mutation negative Czech probands and 3 probands of Slovak origin were screened for large deletions encompassing the APC gene. Mutation screening was performed using denaturing gradient gel electrophoresis and/or protein truncation test. DNA fragments showing an aberrant electrophoretic banding pattern were sequenced. Screening for large deletions was performed by multiplex ligation dependent probe amplification. The extent of deletions was analyzed using following microsatellite markers: D5S299, D5S82, D5S134 and D5S346. RESULTS: In the set of Czech and Slovak patients, we identified 46 germline mutations among 74 unrelated probands. Total mutation capture is 62,2% including large deletions. Thirty seven mutations were detected in 49 patients presenting a classical FAP phenotype (75,5%) and 9 mutations in 25 patients with attenuated FAP (36%). We report 20 novel germline APC mutations and 3 large deletions (6%) encompassing the whole-gene deletions and/or exon 14 deletion. In the patients with novel mutations, correlations of the mutation localization are discussed in context of the classical and/or attenuated phenotype of the disease. CONCLUSION: The results of the molecular genetic testing are used both in the establishment of the predictive diagnosis and in the clinical management of patients. In some cases this study has also shown the difficulty to classify clinically between the classical and the attenuated form of FAP according to the established criteria. Interfamilial and/or intrafamilial phenotype variability was also confirmed in some cases which did not fit well with predicted genotype-phenotype correlation. All these findings have to be taken into consideration both in the genetic counselling and in the patient care.


Asunto(s)
Poliposis Adenomatosa del Colon/genética , Genes APC , Mutación de Línea Germinal , Secuencia de Bases , República Checa , Exones , Eliminación de Gen , Humanos , Datos de Secuencia Molecular , Fenotipo , Eslovaquia
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