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1.
Br J Haematol ; 201(5): 874-886, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36896699

RESUMO

For chronic lymphocytic leukaemia (CLL), targeted drugs have become the standard of care, in particular for second-line treatment. In this study, overall survival (OS), treatment-free survival (TFS) and adverse events (AE) were registered retrospectively in a Danish population-based cohort upon second-line treatment for CLL. Data were collected from medical records and the Danish National CLL register. For 286 patients receiving second-line treatment, three-year TFS was higher upon targeted treatment (ibrutinib/venetoclax/idelalisib) [63%, 95% confidence interval (CI) 50%-76%] compared with fludarabine, cyclophosphamide and rituximab or bendamustine and rituximab (FCR/BR) (37%, CI: 26%-48%) and chlorambucil+/-CD20-antibody (CD20Clb/Clb) (22%, CI: 10%-33%). Upon targeted treatment, three-year OS estimates were higher for targeted treatment (79%, CI: 68%-91%) compared with FCR/BR (70%, CI: 60%-81%) or CD20Clb/Clb (60%, CI: 47%-74%). The most common AEs were infections and haematological AEs; 92% of patients treated with targeted drugs had AEs, 53% of which were severe. Upon FCR/BR and CD20Clb/Clb, AEs were present for 75% and 53% respectively, of which 63% and 31% were severe. These real-world data demonstrate higher TFS and a tendency towards higher OS following targeted second-line treatment for CLL compared to chemoimmunotherapy, also for patients who may be frailer and more comorbid.


Assuntos
Leucemia Linfocítica Crônica de Células B , Humanos , Rituximab , Estudos Retrospectivos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Ciclofosfamida , Clorambucila/efeitos adversos , Cloridrato de Bendamustina/uso terapêutico
2.
Genomics ; 114(6): 110510, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36272495

RESUMO

Copy-number aberrations (CNAs) are assessed using FISH analysis in diagnostics of chronic lymphocytic leukemia (CLL), but CNAs can also be extrapolated from Illumina BeadChips developed for genome-wide methylation microarray screening. Increasing numbers of microarray data-sets are available from diagnostic samples, making it useful to assess the potential in CNA diagnostics. We benchmarked the limitations of CNA testing from two Illumina BeadChips (EPIC and 450k) and using two common packages for analysis (conumee and ChAMP) to FISH-based assessment of 11q, 13q, and 17p deletions in 202 CLL samples. Overall, the two packages predicted CNAs with similar accuracy regardless of the microarray type, but lower than FISH-based assessment. We showed that the bioinformatics analysis needs to be adjusted to the specific CNA, as no general settings were identified. Altogether, we were able to predict CNAs using methylation microarray data, however, with limited accuracy, making FISH-based assessment of deletions the superior diagnostic choice.


Assuntos
Leucemia Linfocítica Crônica de Células B , Humanos , Leucemia Linfocítica Crônica de Células B/diagnóstico , Leucemia Linfocítica Crônica de Células B/genética , Biologia Computacional
3.
Haematologica ; 107(4): 877-886, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-34092057

RESUMO

Currently, no molecular biomarker indices are used in standard care to make treatment decisions at diagnosis of chronic lymphocytic leukemia (CLL). We used Infinium MethylationEPIC array data from diagnostic blood samples of 114 CLL patients and developed a procedure to stratify patients based on methylation signatures associated with mutation load of the IGHV gene. This procedure allowed us to predict the time to treatment with a hazard ratio (HR) of 8.34 (95% confidence interval [CI]: 4.54-15.30), as opposed to a HR of 4.35 (95% CI: 2.60-7.28) using IGHV mutation status. Detailed evaluation of 17 cases for which the two classification procedures gave discrepant results showed that these cases were incorrectly classified using IGHV status. Moreover, methylation-based classification stratified patients with different overall survival (HR=1.82; 95% CI: 1.07-3.09), which was not possible using IGHV status. Furthermore, we assessed the performance of the developed classification procedure using published HumanMethylation450 array data for 159 patients for whom information on time to treatment, overall survival and relapse was available. Despite 450K array methylation data not containing all the biomarkers used in our classification procedure, methylation signatures again stratified patients with significantly better accuracy than did IGHV mutation load regarding all available clinical outcomes. Thus, stratification using IGHV-associated methylation signatures may provide better prognostic power than IGHV mutation status.


Assuntos
Leucemia Linfocítica Crônica de Células B , Humanos , Cadeias Pesadas de Imunoglobulinas/genética , Leucemia Linfocítica Crônica de Células B/diagnóstico , Leucemia Linfocítica Crônica de Células B/genética , Leucemia Linfocítica Crônica de Células B/terapia , Metilação , Mutação , Prognóstico
4.
Exp Mol Pathol ; 102(3): 484-491, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28512015

RESUMO

Lung cancer has the highest mortality rate amongst human cancers and the majority of deaths can be attributed to metastatic spread. The miR-34 family includes three tumor suppressive miRs: miR-34a, miR-34b and miR-34c. miR-34 downregulation is a frequent observation in human malignancies and is often attributed to hypermethylation of the miR-34a and miR-34b/c promoters. Here, the potential association between aberrant miR-34 expression and promoter methylation and distant metastases formation in lung adenocarcinoma (LAC) is investigated. The expression levels of miR-34a, miR-34b and miR-34c, as well as the methylation status of the miR-34a and miR-34b/c promoters were determined in a LAC patient cohort comprising 26 non-metastasizing and 26 metastasizing primary LACs, as well as 24 paired distant metastases and 25 tumor-adjacent normal lung samples using RT-qPCR and Methylation-Sensitive High Resolution Melting (MS-HRM) analysis. No difference in expression was observed for miR-34a when comparing metastasizing and non-metastasizing LACs (p=0.793). For both miR-34b and miR-34c, a significantly lower expression level was determined in metastasizing LACs compared to non-metastasizing LACs (p=0.0005 and p=0.002) with similarly decreased expression levels observed in the paired distant metastases. Hypermethylation was detected in 35/51 LACs compared to 0/25 tumor-adjacent normal lungs for the miR-34a promoter (p<0.0001). Similarly, 18/51 LACs compared to 1/25 tumor-adjacent normal lungs showed hypermethylation of the miR-34b/c promoter (p=0.003). No difference in methylation was observed between metastasizing and non-metastasizing LACs for neither the miR-34a (p=0.832) nor the miR-34b/c (p=0.900) promoter. In conclusion, miR-34a and miR-34b/c promoter hypermethylation is a frequent event in LAC occurring in 68.7% and 35.3% of tested cases (n=51), respectively. Low miR-34b and miR-34c expression was associated with distant metastases formation in LAC. These changes can be targeted as novel biomarkers in LAC.


Assuntos
Adenocarcinoma/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/genética , MicroRNAs/genética , Adenocarcinoma de Pulmão , Metilação de DNA , Humanos , MicroRNAs/metabolismo , Metástase Neoplásica/genética , Regiões Promotoras Genéticas
5.
BMC Public Health ; 17(1): 860, 2017 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-29100500

RESUMO

BACKGROUND: Social relations influence mental health through different pathways. To capture the complexity of social relations, it is beneficial to consider both the structural (e.g., reachability of social network and social integration) and functional (e.g., instrumental and emotional support) aspects of the concept. Both aspects are rarely investigated simultaneously. This study aimed to examine the association between the structural and functional aspects of social relations and poor mental health. METHODS: The study was designed as a cross-sectional register study. We used data on mental health and social relations from 15,839 individuals aged 16-92 years with a mean age of 49.0 years (SD 17.9) who responded to The North Denmark Region Health Survey 2013 among residents in Northern Jutland, Denmark. The 12-Item Short-Form Health Survey measured mental health; a cut-off point of 44.5 was used to dichotomize participants into poor and good mental health. The categorization of social relations was inspired by Berkman et al.'s conceptual model of social relations and health. The analyses were performed with survey logistic regression. RESULTS: We found that 21.6% (n = 3422) of participants reported poor mental health, and 59% (n = 2020) of these were women. Being in contact with family and friends less than once a month statistically significantly increased the risk for poor mental health (Family OR = 1.78, 95% CI = 1.51-2.10 and Friends OR = 2.65, 95% CI = 2.30-3.06). The individuals who were not in contact with their network as often as they liked had a significantly higher risk for poor mental health (OR = 2.40, 95% CI = 2.20-2.62). Lack of instrumental support was associated with a higher risk for poor mental health (OR = 2.81, 95% CI = 2.26-3.48). We found an interaction between age and emotional support; the youngest population had the highest risk for poor mental health when they did not have access to emotional support (Young OR = 5.26, 95% CI = 3.91-7.09; Adult OR = 3.69, 95% CI = 3.17-4.30; and Elderly OR = 2.73, 95% CI = 2.23-3.34). CONCLUSIONS: Both structural and functional aspects of social relations were associated with poor mental health in our study. Rarely being in contact with friends and a lack of network reachability were associated with poor mental health. Likewise, low levels of emotional and instrumental support were associated with poor mental health.


Assuntos
Família/psicologia , Amigos/psicologia , Relações Interpessoais , Transtornos Mentais/epidemiologia , Apoio Social , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Dinamarca/epidemiologia , Feminino , Inquéritos Epidemiológicos , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Medição de Risco , Adulto Jovem
6.
BMC Musculoskelet Disord ; 18(1): 557, 2017 12 29.
Artigo em Inglês | MEDLINE | ID: mdl-29284454

RESUMO

BACKGROUND: Transplanting myogenic cells and scaffolds for tissue engineering in skeletal muscle have shown inconsistent results. One of the limiting factors is neovascularization at the recipient site. Low intensity shockwave therapy (Li-SWT) has been linked to increased tissue regeneration and vascularization, both integral to survival and integration of transplanted cells. This study was conducted to demonstrate the response of myoblasts and skeletal muscle to Li-SWT. METHOD: Primary isolated human myoblasts and explants were treated with low intensity shockwaves and subsequently cell viability, proliferation and differentiation were tested. Cardiotoxin induced injury was created in tibialis anterior muscles of 28 mice, and two days later, the lesions were treated with 500 impulses of Li-SWT on one of the legs. The treatment was repeated every third day of the period and ended on day 14 after cardiotoxin injection.. The animals were followed up and documented up to 21 days after cardiotoxin injury. RESULTS: Li-SWT had no significant effect on cell death, proliferation, differentiation and migration, the explants however showed decreased adhesion. In the animal experiments, qPCR studies revealed a significantly increased expression of apoptotic, angiogenic and myogenic genes; expression of Bax, Bcl2, Casp3, eNOS, Pax7, Myf5 and Met was increased in the early phase of regeneration in the Li-SWT treated hind limbs. Furthermore, a late accumulative angiogenic effect was demonstrated in the Li-SWT treated limbs by a significantly increased expression of Angpt1, eNOS, iNOS, Vegfa, and Pecam1. CONCLUSION: Treatment was associated with an early upregulation in expression of selected apoptotic, pro-inflammatory, angiogenic and satellite cell activating genes after muscle injury. It also showed a late incremental effect on expression of pro-angiogenic genes. However, we found no changes in the number of PAX7 positive cells or blood vessel density in Li-SWT treated and control muscle. Furthermore, Li-SWT in the selected doses did not decrease survival, proliferation or differentiation of myoblasts in vitro.


Assuntos
Desenvolvimento Muscular/efeitos da radiação , Músculo Esquelético/efeitos da radiação , Mioblastos/efeitos da radiação , Ondas Ultrassônicas , Animais , Diferenciação Celular/fisiologia , Diferenciação Celular/efeitos da radiação , Células Cultivadas , Feminino , Ondas de Choque de Alta Energia , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Desenvolvimento Muscular/fisiologia , Músculo Esquelético/citologia , Músculo Esquelético/fisiologia , Mioblastos/fisiologia
7.
Anal Biochem ; 468: 50-8, 2015 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-25277813

RESUMO

Formalin fixation has been the standard method for conservation of clinical specimens for decades. However, a major drawback is the high degradation of nucleic acids, which complicates its use in genome-wide analyses. Unbiased identification of biomarkers, however, requires genome-wide studies, precluding the use of the valuable archives of specimens with long-term follow-up data. Therefore, restoration protocols for DNA from formalin-fixed and paraffin-embedded (FFPE) samples have been developed, although they are cost-intensive and time-consuming. An alternative to FFPE and snap-freezing is the PAXgene Tissue System, developed for simultaneous preservation of morphology, proteins, and nucleic acids. In the current study, we compared the performance of DNA from either PAXgene or formalin-fixed tissues to snap-frozen material for genome-wide DNA methylation analysis using the Illumina 450K BeadChip. Quantitative DNA methylation analysis demonstrated that the methylation profile in PAXgene-fixed tissues showed, in comparison with restored FFPE samples, a higher concordance with the profile detected in frozen samples. We demonstrate, for the first time, that DNA from PAXgene conserved tissue performs better compared with restored FFPE DNA in genome-wide DNA methylation analysis. In addition, DNA from PAXgene tissue can be directly used on the array without prior restoration, rendering the analytical process significantly more time- and cost-effective.


Assuntos
Metilação de DNA , DNA/análise , DNA/química , Adenocarcinoma/química , Adenocarcinoma de Pulmão , Ilhas de CpG , DNA de Neoplasias/análise , DNA de Neoplasias/química , Formaldeído , Genoma Humano , Humanos , Pulmão/química , Neoplasias Pulmonares/química , Inclusão em Parafina , Reprodutibilidade dos Testes , Fixação de Tecidos
8.
Exp Mol Pathol ; 99(3): 632-40, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26551081

RESUMO

Readily accessible formalin-fixed paraffin embedded (FFPE) tissues are a highly valuable source of genetic material for molecular analyses in both research and in vitro diagnostics but frequently genetic material in those samples is highly degraded. With locus-specific methylation changes being widely investigated for use as biomarkers in various aspects of clinical disease management, we aimed to evaluate to what extent standard laboratory procedures can approximate the quality of the DNA extracted from FFPE samples prior to methylation analyses. DNA quality in 107 FFPE non-small cell lung cancer (NSCLC) samples was evaluated using spectrophotometry and gel electrophoresis. Subsequently, the quality assessment results were correlated with the results of locus specific methylation assessment with methylation sensitive high resolution melting (MS-HRM). The correlation of template quality with PCR amplification performance and HRM based methylation detection indicated a significant influence of DNA quality on PCR amplification but not on methylation assessment. In conclusion, standard laboratory procedures fairly well approximate DNA degradation of FFPE samples and DNA degradation does not seem to considerably affect locus-specific methylation assessment by MS-HRM.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Metilação de DNA/genética , DNA de Neoplasias/análise , Técnicas Genéticas , Neoplasias Pulmonares/genética , DNA de Neoplasias/metabolismo , Formaldeído , Humanos , Inclusão em Parafina , Reação em Cadeia da Polimerase , Fixação de Tecidos
9.
Toxicol Pathol ; 43(6): 890-2, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25717081

RESUMO

Incidental findings in the rat eye are not uncommon in acute and long-term toxicological studies. These findings can be associated with a number of causes unrelated to treatment with the test article, including congenital malformation, trauma, infection, metabolic disease, genetic predisposition, and age-related changes. The occurrence of pigment deposition in the retina of Wistar Hannover (Crl:WI (Han)) rats in a 4-week toxicity study is reported in this communication. The microscopic examination of the eyes in the 4-week toxicity study revealed focal yellow-brown pigment deposits in the retina, mainly located in the ganglion cell layer. The retinal pigment deposits were randomly distributed in the control and treated groups and were considered incidental. The deposits were clearly positive for ferric iron in the Perls' stain but not for lipofuscin by the Schmorl's and Long Ziehl-Neelsen methods. The iron-containing pigment is likely to represent hemosiderin accumulation after retinal micro-hemorrhage or could be indicative of the normal intraretinal iron transport and turnover.


Assuntos
Retina/metabolismo , Epitélio Pigmentado da Retina/metabolismo , Pigmentos da Retina/metabolismo , Animais , Corantes , Olho/patologia , Feminino , Compostos Férricos/metabolismo , Hemossiderina/análise , Lipofuscina/química , Masculino , Ratos , Ratos Wistar , Retina/química , Células Ganglionares da Retina/metabolismo , Células Ganglionares da Retina/patologia , Hemorragia Retiniana/patologia , Epitélio Pigmentado da Retina/química , Pigmentos da Retina/química , Fixação de Tecidos
10.
Breast Cancer Res ; 16(1): R17, 2014 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-24490656

RESUMO

INTRODUCTION: Despite similar clinical and pathological features, large numbers of breast cancer patients experience different outcomes of the disease. This, together with the fact that the incidence of breast cancer is growing worldwide, emphasizes an urgent need for identification of new biomarkers for early cancer detection and stratification of patients. METHODS: We used ultrahigh-resolution microarrays to compare genomewide methylation patterns of breast carcinomas (n = 20) and nonmalignant breast tissue (n = 5). Biomarker properties of a subset of discovered differentially methylated regions (DMRs) were validated using methylation-sensitive high-resolution melting (MS-HRM) in a case-control study on a panel of breast carcinomas (n = 275) and non-malignant controls (n = 74). RESULTS: On the basis of microarray results, we selected 19 DMRs for large-scale screening of cases and controls. Analysis of the screening results showed that all DMRs tested displayed significant gains of methylation in the cancer tissue compared to the levels in control tissue. Interestingly, we observed two types of locus-specific methylation, with loci undergoing either predominantly full or heterogeneous methylation during carcinogenesis. Almost all tested DMRs (17 of 19) displayed low-level methylation in nonmalignant breast tissue, independently of locus-specific methylation patterns in cases. CONCLUSIONS: Specific loci can undergo either heterogeneous or full methylation during carcinogenesis, and loci hypermethylated in cancer frequently show low-level methylation in nonmalignant tissue.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Metilação de DNA/genética , Sequência de Bases , Estudos de Casos e Controles , Ilhas de CpG/genética , Epigênese Genética , Feminino , Humanos , Análise de Sequência de DNA , Análise Serial de Tecidos
11.
J Assist Reprod Genet ; 31(11): 1427-36, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25241129

RESUMO

PURPOSE: To provide an improved platform for simple, reliable, and cost-effective genotyping. BACKGROUND: Modern fertility treatments are becoming increasingly individualized in an attempt to optimise the follicular response and reproductive outcome, following controlled ovarian stimulation. As the field of pharmacogenetics evolve, genetic biomarkers such as polymorphisms of the follicle stimulating hormone receptor (FSHR) may be included as a predictive tool for individualized fertility treatment. However, the currently available genotyping methods are expensive, time-consuming or have a limited analytical sensitivity. Here, we present a novel version of "competitive amplification of differentially melting amplicons" (CADMA), providing an improved platform for simple, reliable, and cost-effective genotyping. METHODS: Two CADMA based assays were designed for the two common polymorphisms of the FSHR gene: rs6165 (c.919A > G, p. Thr307Ala, FSHR 307) and rs6166 (c.2039A > G, p. Asn680Ser, FSHR 680). To evaluate the reliability of the new CADMA-based assays, the genotyping results were compared with two conventional PCR based genotyping methods; allele-specific PCR (AS-PCR) and Sanger sequencing. RESULTS: The genotype frequencies for both polymorphisms were 35 % (TT), 42 % (CT), and 23 % (CC), respectively. A 100 % accordance was observed between the CADMA-based genotyping results and sequencing results, whereas 5 discrepancies were observed between the AS-PCR results and the CADMA-based genotyping results. Comparing the CADMA-based assays to (AS-PCR) and Sanger sequencing, the CADMA based assays showed an improved analytical sensitivity and a wider applicability. CONCLUSIONS: The new assays provide a reliable, fast and user-friendly genotyping method facilitating a wider implication in clinical practise.


Assuntos
Técnicas de Genotipagem , Polimorfismo Genético , Receptores do FSH/genética , Técnicas de Amplificação de Ácido Nucleico , Análise de Sequência de DNA
12.
Dan Med J ; 71(1)2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38235985

RESUMO

INTRODUCTION: Outpatient (OPT) thyroid surgery is increasing, with patient selection being pivotal for safety. While numerous studies exist, most are retrospective and encompass both benign and malignant cases. METHODS: We conducted a randomised clinical trial on patients undergoing hemithyroidectomy for benign thyroid disease. Participants were assigned to OPT or inpatient groups. We collected data on complications, failure to discharge on surgery day, post-operative pain, nausea, sleep quality and patient satisfaction. RESULTS: Among 97 patients, 27.5% (14/51) in the OPT group could not be discharged on the day of surgery due to minor complications, primarily nausea (36%) and neck swelling (29%). No reoperations were needed. Though OPT patients exhibited a higher rate of minor complications (29%), they reported less post-operative nausea, better sleep and a faster return to normal activity. CONCLUSIONS: Discharge on the day of surgery is not always possible with OPT thyroid surgery. However, our findings suggest that OPT hemithyroidectomy for benign cases can be both safe and feasible for a selected group of patients. FUNDING: None TRIAL REGISTRATION. CLINICALTRIALS: gov Identifier: NCT02891252.


Assuntos
Pacientes Ambulatoriais , Tireoidectomia , Humanos , Estudos Retrospectivos , Tireoidectomia/efeitos adversos , Glândula Tireoide , Náusea
13.
Hum Mutat ; 33(1): 264-71, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21901793

RESUMO

Sensitive and specific mutation detection is of particular importance in cancer diagnostics, prognostics, and individualized patient treatment. However, the majority of molecular methodologies that have been developed with the aim of increasing the sensitivity of mutation testing have drawbacks in terms of specificity, convenience, or costs. Here, we have established a new method, Competitive Amplification of Differentially Melting Amplicons (CADMA), which allows very sensitive and specific detection of all mutation types. The principle of the method is to amplify wild-type and mutated sequences simultaneously using a three-primer system. A mutation-specific primer is designed to introduce melting temperature decreasing mutations in the resulting mutated amplicon, while a second overlapping primer is designed to amplify both wild-type and mutated sequences. When combined with a third common primer very sensitive mutation detection becomes possible, when using high-resolution melting (HRM) as detection platform. The introduction of melting temperature decreasing mutations in the mutated amplicon also allows for further mutation enrichment by fast coamplification at lower denaturation temperature PCR (COLD-PCR). For proof-of-concept, we have designed CADMA assays for clinically relevant BRAF, EGFR, KRAS, and PIK3CA mutations, which are sensitive to, between 0.025% and 0.25%, mutated alleles in a wild-type background. In conclusion, CADMA enables highly sensitive and specific mutation detection by HRM analysis.


Assuntos
Adenocarcinoma/genética , Neoplasias do Colo/genética , Análise Mutacional de DNA/métodos , DNA/genética , Mutação , Reação em Cadeia da Polimerase , Adenocarcinoma/diagnóstico , Sequência de Bases , Linhagem Celular Tumoral , Neoplasias do Colo/diagnóstico , Primers do DNA/genética , Congelamento , Genes ras , Temperatura Alta , Humanos , Dados de Sequência Molecular , Desnaturação de Ácido Nucleico , Proteínas Proto-Oncogênicas B-raf/genética , Sensibilidade e Especificidade , Temperatura de Transição
14.
BMC Cancer ; 12: 548, 2012 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-23173730

RESUMO

BACKGROUND: Cancer is an extremely heterogeneous group of diseases traditionally categorized according to tissue of origin. However, even among patients with the same cancer subtype the cellular alterations at the molecular level are often very different. Several new therapies targeting specific molecular changes found in individual patients have initiated the era of personalized therapy and significantly improved patient care. In metastatic colorectal cancer (mCRC) a selected group of patients with wild-type KRAS respond to antibodies against the epidermal growth factor receptor (EGFR). Testing for KRAS mutations is now required prior to anti-EGFR treatment, however, less sensitive methods based on conventional PCR regularly fail to detect KRAS mutations in clinical samples. METHODS: We have developed sensitive and specific assays for detection of the seven most common KRAS mutations based on a novel methodology named Competitive Amplification of Differentially Melting Amplicons (CADMA). The clinical applicability of these assays was assessed by analyzing 100 colorectal cancer samples, for which KRAS mutation status has been evaluated by the commercially available TheraScreen® KRAS mutation kit. RESULTS: The CADMA assays were sensitive to at least 0.5% mutant alleles in a wild-type background when using 50 nanograms of DNA in the reactions. Consensus between CADMA and the TheraScreen kit was observed in 96% of the colorectal cancer samples. In cases where disagreement was observed the CADMA result could be confirmed by a previously published assay based on TaqMan probes and by fast COLD-PCR followed by Sanger sequencing. CONCLUSIONS: The high analytical sensitivity and specificity of CADMA may increase diagnostic sensitivity and specificity of KRAS mutation testing in mCRC patients.


Assuntos
Neoplasias Colorretais/genética , Análise Mutacional de DNA/métodos , Mutação , Proteínas Proto-Oncogênicas/genética , Proteínas ras/genética , Linhagem Celular Tumoral , Neoplasias Colorretais/patologia , DNA de Neoplasias/química , DNA de Neoplasias/genética , Humanos , Reação em Cadeia da Polimerase , Proteínas Proto-Oncogênicas p21(ras) , Reprodutibilidade dos Testes , Análise de Sequência de DNA
15.
Genes (Basel) ; 13(8)2022 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-36011328

RESUMO

Pyrosequencing is one of the technologies widely used for quantitative methylation assessment. The protocol of pyrosequencing experiment consists of PCR amplification of a locus of interest and subsequent sequencing via synthesis of the amplified PCR product. As the PCR in this protocol utilizes one primer set for the amplification of a template originating from both methylated and non-methylated versions of the analysed locus, the unequal amplification of one of the templates may affect the methylation level assessment by pyrosequencing. We have investigated whether the unequal amplification of one of the templates challenges the quantitative properties of the pyrosequencing technology. Our results show that the sensitivity and dynamic range of pyrosequencing can be significantly affected by unequal amplification of the methylated and non-methylated version of the locus of interest in an assay specific manner. Thus, the assessment of the effect of unequal template amplification on the performances of the specific pyrosequencing assay is necessary before using the assay either in research or especially in diagnostic settings.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala , Técnicas de Amplificação de Ácido Nucleico , Reação em Cadeia da Polimerase/métodos
16.
PLoS One ; 17(9): e0273058, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36067175

RESUMO

Testing for disease-related DNA methylation changes provides clinically relevant information in personalized patient care. Methylation-Sensitive High-Resolution Melting (MS-HRM) is a method used for measuring methylation changes and has already been used in diagnostic settings. This method utilizes one set of primers that initiate the amplification of both methylated and non-methylated templates. Therefore, the quantification of the methylation levels using MS-HRM is hampered by the PCR bias phenomenon. Some approaches have been proposed to calculate the methylation level of samples using the high-resolution melting (HRM) curves. However, limitations of the methylation calculation using MS-HRM have not been evaluated systematically and comprehensively. We used the Area Under the Curve (AUC), a derivative of the HRM curves, and least square approximation (LSA) to establish a procedure that allowed us to infer methylation levels in an MS-HRM experiment and assess the limitations of that procedure for the assays' specific methylation level measurement. The developed procedure allowed, with certain limitations, estimation of the methylation levels using HRM curves.


Assuntos
Metilação de DNA , Primers do DNA , Humanos , Reação em Cadeia da Polimerase/métodos
17.
Int J Cancer ; 129(12): 2855-66, 2011 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-21400501

RESUMO

In our study, whole-genome methylation arrays were applied to identify novel genes with tumor specific DNA methylation of promoter CpG islands in pre-malignant and malignant colorectal lesions. Using a combination of Illumina HumanMethylation27 beadchips, Methylation-Sensitive High Resolution Melting (MS-HRM) analysis, and Exon arrays (Affymetrix) the DNA methylation pattern of ∼14,000 genes and their transcript levels were investigated in six normal mucosas, six adenomas and 30 MSI and MSS carcinomas. Sixty eight genes with tumor-specific hypermethylation were identified (p < 0.005). Identified hypermethylated sites were validated in an independent sample set of eight normal mucosas, 12 adenomas, 40 MSS and nine MSI cancer samples. The methylation patterns of 15 selected genes, hypermethylated in adenomas and carcinomas (FLI1, ST6GALNAC5, TWIST1, ADHFE1, JAM2, IRF4, CNRIP1, NRG1 and EYA4), in carcinomas only (ABHD9, AOX1 and RERG), or in MSI but not MSS carcinomas (RAMP2, DSC3 and MLH1) were validated using MS-HRM. Four of these genes (MLH1, AOX1, EYA4 and TWIST1) had previously been reported to be hypermethylated in CRC. Eleven genes, not previously known to be affected by CRC specific hypermethylation, were identified and validated. Inverse correlation to gene expression was observed for six of the 15 genes with Spearman correlation coefficients ranging from -0.39 to -0.60. For six of these genes the altered methylation patterns had a profound transcriptional association, indicating that methylation of these genes may play a direct regulatory role. The hypermethylation changes often occurred already in adenomas, indicating that they may be used as biomarkers for early detection of CRC.


Assuntos
Adenoma/genética , Carcinoma/genética , Neoplasias Colorretais/genética , Ilhas de CpG/genética , Metilação de DNA , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Neuregulina-1/metabolismo
18.
Future Oncol ; 7(12): 1451-5, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22112320

RESUMO

There is no doubt that aberrant somatic (tumor-specific) methylation significantly contributes to the carcinogenic process. However, the question of the relevance of methylation pattern changes, acquired by individuals during their development and lifetime or inherited through the germline, to the pathology of different diseases, remains open. Recently, a number of studies addressed the question of the prevalence of aberrant methylation of cancer-related genes in peripheral blood leukocyte (PBL) DNA and indicated a strong possibility that the presence of constitutional methylation of different genes might predispose for cancer development. Here, we have used the methlyation-sensitive high-resolution melting approach to examine the methylation status of the BRCA1, BRCA2, APC, RASSF1A and RARß2 genes in PBLs of a group of women diagnosed with breast cancer, and an age-matched control group with no signs of breast cancer. No significant differences in the frequency of methylation of the above genes were found between cases and controls in our study. Hence, testing for the presence of methylation of cancer-related genes in PBL DNA from women diagnosed with sporadic breast cancer and classified for testing without any pathological or clinical selection criteria does not seem to have clinical applicability.


Assuntos
Biomarcadores Tumorais/sangue , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/genética , Metilação de DNA , DNA de Neoplasias/sangue , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Leucócitos Mononucleares/metabolismo , Pessoa de Meia-Idade , Regiões Promotoras Genéticas
19.
Sci Rep ; 11(1): 9846, 2021 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-33972578

RESUMO

The anticancer activity of bortezomib (BTZ) has been increasingly studied in a number of indications and promising results for the use of this treatment have been shown in neuroblastoma. As BTZ treatment is usually administered in cycles, the development of resistance and side effects in patients undergoing therapy with BTZ remains a major challenge for the clinical usage of this compound. Common resistance development also means that certain cells are able to survive BTZ treatment and bypass molecular mechanisms that render BTZ anticancer activity. We studied the methylome of neuroblastoma cells that survived BTZ treatment. Our results indicate that BTZ induces pronounced genome wide methylation changes in cells which recovered from the treatment. Functional analyses of identified methylation changes demonstrated they were involved in key cancer pathology pathways. These changes may allow the cells to bypass the primary anticancer activity of BTZ and develop a treatment resistant and proliferative phenotype. To study whether cells surviving BTZ treatment acquire a proliferative phenotype, we repeatedly treated cells which recovered from the first round of BTZ treatment. The repetitive treatment led to induction of the extraordinary proliferative potential of the cells, that increased with subsequent treatments. As we did not observe similar effects in cells that survived treatment with lenalidomide, and non-treated cells cultured under the same experimental conditions, this phenomenon seems to be BTZ specific. Overall, our results indicate that methylation changes may play major role in the development of BTZ resistance.


Assuntos
Antineoplásicos/farmacologia , Bortezomib/farmacologia , Metilação de DNA/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Neuroblastoma/tratamento farmacológico , Antineoplásicos/uso terapêutico , Bortezomib/uso terapêutico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Sobrevivência Celular/genética , Resistencia a Medicamentos Antineoplásicos/genética , Epigênese Genética/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Lenalidomida/farmacologia , Lenalidomida/uso terapêutico , Neuroblastoma/genética
20.
MAbs ; 13(1): 1994690, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34709986

RESUMO

Alpha-synuclein is a 15 kDa protein associated with neurodegenerative diseases such as Parkinson disease and multiple-system atrophy where pathological forms of alpha-synuclein aggregate and become neurotoxic. Here we describe the nonclinical program to support a first-in-human (FIH) single ascending dose (SAD) study for Lu AF82422, a human recombinant, anti-alpha-synuclein monoclonal antibody (mAb) in development for treatment of synucleinopathies. Alpha-synuclein is primarily expressed in brain, peripheral nerves and in blood cells. A tissue cross-reactivity assessment showed that Lu AF82422 binding was generally restricted to nervous tissues. Flow cytometry analysis did not show extracellular surface binding of Lu AF82422 to human platelets, erythrocytes, granulocytes, or lymphocytes, but to a low fraction of monocytes, without any functional consequences on activation or phagocytic capacity. A single dose pharmacokinetic (PK) study in cynomolgus monkeys with dose levels of 1-30 mg/kg confirmed PK properties in the expected range for a mAb with a soluble target, and target engagement was shown as a decrease in free alpha-synuclein in plasma. Four-week repeat-dose toxicity studies were conducted in rats and cynomolgus monkeys at doses up to 600 mg/kg administered intravenously every 10 days. Results showed no treatment-related adverse findings and the no-observed-adverse-effect-level was the highest dose tested. Target engagement was shown in plasma and cerebrospinal fluid. Taken together, the nonclinical data indicated no safety signal of concern and provided adequate safety margins between observed safe doses in animals and the planned dose levels in the FIH SAD study.


Assuntos
Doença de Parkinson , Sinucleinopatias , Animais , Anticorpos Monoclonais/farmacocinética , Imunoglobulina G , Ratos , alfa-Sinucleína
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