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2.
Ann Surg Oncol ; 31(6): 3758-3768, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38453767

RESUMO

BACKGROUND: Before 2016, patients with isolated synchronous colorectal peritoneal metastases (PMCRC) diagnosed in expert centers had a higher odds of undergoing cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS-HIPEC) and better overall survival (OS) than those diagnosed in referring centers. Nationwide efforts were initiated to increase awareness and improve referral networks. METHODS: This nationwide study aimed to evaluate whether the between-center differences in odds of undergoing CRS-HIPEC and OS have reduced since these national efforts were initiated. All patients with isolated synchronous PMCRC diagnosed between 2009 and 2021 were identified from the Netherlands Cancer Registry. Associations between hospital of diagnosis and the odds of undergoing CRS-HIPEC, as well as OS, were assessed using multilevel multivariable regression analyses for two periods (2009-2015 and 2016-2021). RESULTS: In total, 3948 patients were included. The percentage of patients undergoing CRS-HIPEC increased from 17.2% in 2009-2015 (25.4% in expert centers, 16.5% in referring centers), to 23.4% in 2016-2021 (30.2% in expert centers, 22.6% in referring centers). In 2009-2015, compared with diagnosis in a referring center, diagnosis in a HIPEC center showed a higher odds of undergoing CRS-HIPEC (odds ratio [OR] 1.64, 95% confidence interval [CI] 1.02-2.67) and better survival (hazard ratio [HR] 0.80, 95% CI 0.66-0.96). In 2016-2021, there were no differences in the odds of undergoing CRS-HIPEC between patients diagnosed in HIPEC centers versus referring centers (OR 1.27, 95% CI 0.76-2.13) and survival (HR 1.00, 95% CI 0.76-1.32). CONCLUSION: Previously observed differences in odds of undergoing CRS-HIPEC were no longer present. Increased awareness and the harmonization of treatment for PMCRC may have contributed to equal access to care and a similar chance of survival at a national level.


Assuntos
Neoplasias Colorretais , Procedimentos Cirúrgicos de Citorredução , Quimioterapia Intraperitoneal Hipertérmica , Neoplasias Peritoneais , Humanos , Neoplasias Peritoneais/terapia , Neoplasias Peritoneais/secundário , Neoplasias Peritoneais/mortalidade , Procedimentos Cirúrgicos de Citorredução/mortalidade , Masculino , Feminino , Neoplasias Colorretais/patologia , Neoplasias Colorretais/terapia , Neoplasias Colorretais/mortalidade , Pessoa de Meia-Idade , Taxa de Sobrevida , Terapia Combinada , Idoso , Prognóstico , Seguimentos , Países Baixos , Acessibilidade aos Serviços de Saúde , Sistema de Registros , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico
4.
J Shoulder Elbow Surg ; 33(1): 145-155, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37689102

RESUMO

BACKGROUND: Overloading of the elbow joint prosthesis following total elbow arthroplasty can lead to implant failure. Joint moments during daily activities are not well contextualized for a prosthesis's failure limits, and the effect of the current postoperative instruction on elbow joint loading is unclear. This study investigates the difference in elbow joint moments between simulated daily tasks and between flexion-extension, pronation-supination, and varus-valgus movement directions. Additionally, the effect of the current postoperative instruction on elbow joint load is examined. METHODS: Nine healthy participants (age 45.8 ± 17 years, 3 males) performed 8 tasks; driving a car, opening a door, rising from a chair, lifting, sliding, combing hair, drinking, emptying cup, without and with the instruction "not lifting more than 1 kg." Upper limb kinematics and hand contact forces were measured. Elbow joint angles and net moments were analyzed using inverse dynamic analysis, where the net moments are estimated from movement data and external forces. RESULTS: Peak elbow joint moments differed significantly between tasks (P < .01) and movement directions (P < .01). The most and least demanding tasks were, rising from a chair (13.4 Nm extension, 5.0 Nm supination, and 15.2 Nm valgus) and sliding (4.3 Nm flexion, 1.7 Nm supination, and 2.6 Nm varus). Net moments were significantly reduced after instruction only in the chair task (P < .01). CONCLUSION: This study analyzed elbow joint moments in different directions during daily tasks. The outcomes question whether postoperative instruction can lead to decreasing elbow loads. Future research might focus on reducing elbow loads in the flexion-extension and varus-valgus directions.


Assuntos
Artroplastia de Substituição do Cotovelo , Articulação do Cotovelo , Masculino , Humanos , Adulto , Pessoa de Meia-Idade , Articulação do Cotovelo/cirurgia , Cotovelo , Atividades Cotidianas , Movimento , Fenômenos Biomecânicos
5.
Acta Oncol ; 62(8): 842-852, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37548150

RESUMO

BACKGROUND: This study investigates whether inequalities in the utilization of resection and/or ablation for synchronous colorectal liver metastases (SCLM) between patients diagnosed in expert and non-expert hospitals changed since a multi-hospital network started. MATERIALS AND METHODS: Patients diagnosed with SCLM between 2009 and 2020 were included. The likelihood of receiving ablation and/or resection was analyzed in the prenetwork (2009-2012), startup (2013-2016), and matured-network (2017-2020) periods. RESULTS: Nationwide, 13.981patients were diagnosed between 2009 and 2020, of whom 1.624 were diagnosed in the network. Of patients diagnosed in the network's expert hospitals, 36.7% received ablation and/or resection versus 28.3% in nonexpert hospitals (p < 0.01). The odds ratio (OR) of receiving ablation and/or resection for patients diagnosed in expert versus nonexpert hospitals increased from 1.38 (p = 0.581, pre-network), to 1.66 (p = 0.108, startup), to 2.48 (p = 0.090, matured-network). Nationwide, the same trend occurred (respectively OR 1.41, p = 0.011; OR 2.23, p < 0.001; OR 3.20, p < 0.001). CONCLUSIONS: Patients diagnosed in expert hospitals were more likely to receive ablation and/or resection for SCLM than patients diagnosed in non-expert hospitals. This difference increased over time despite the startup of a multi-hospital network. Establishing a multi-hospital network did not have an effect on reducing the existing unequal odds of receiving specialized treatment. SYNOPSIS: Specialized oncology treatments are increasingly provided through multi-hospital networks. However, scant empirical evidence on the effectiveness of these networks exists. This study analyzes whether a regional multi-hospital network was able to improve equal access to specialized oncology treatments.


Assuntos
Neoplasias Colorretais , Neoplasias Hepáticas , Humanos , Hepatectomia , Neoplasias Colorretais/patologia , Neoplasias Hepáticas/secundário , Hospitais , Probabilidade , Resultado do Tratamento
6.
Clin Obes ; 12(2): e12507, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35040265

RESUMO

Postbariatric outcomes may improve by providing an additional preconditioning program (APP) in targeted patients. However, APPs are a demand for health resources while only little and inconsistent evidence consists to support their effectiveness. This cohort study aims to evaluate the effectiveness of APP, by comparing outcomes of patients with and without such APP. We carried out a retrospective single-centre cohort study in a before-after design. Patients signing up for primary gastric bypass or sleeve gastrectomy and eligible for surgery were included if screened as vulnerable patients. Vulnerable patients screened between September 2017 and March 2018 followed an APP and formed the APP-group. Due to a policy change, APPs were no longer performed since September 2018. Vulnerable patients screened between September 2018 and March 2019 thus did not receive an APP (comparator-group). Multidisciplinary follow-up remained unchanged. Endpoints included percentage total weight loss (%TWL), bodyweight, evolution of comorbidities, protein intake, and number of no-shows. The APP-group comprised 231 patients and the comparator-group 153. %TWL differed statistically significantly at 7 (Δ1.5%, p = .01) and 12 months postoperative (Δ2.8%, p < .01) in favour of the comparator-group, as did bodyweight 12 months postoperative (Δ1.8 kg, p < .01). Statistically significant differences were also found in the evolution of comorbidities, protein intake, and the number of no-shows, most in favour for the comparator-group. APP proofed not to be superior to Non-App. It is debatable whether statically significant differences are clinically relevant given their small magnitude. A care pathway without an APP seems at least as effective as a care pathway without.


Assuntos
Cirurgia Bariátrica , Derivação Gástrica , Laparoscopia , Obesidade Mórbida , Estudos de Coortes , Gastrectomia/efeitos adversos , Derivação Gástrica/efeitos adversos , Humanos , Obesidade Mórbida/etiologia , Obesidade Mórbida/cirurgia , Estudos Retrospectivos , Resultado do Tratamento , Redução de Peso
7.
Br J Cancer ; 103(8): 1255-62, 2010 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-20842112

RESUMO

BACKGROUND: Wilms' tumour 1 (WT1) gene was discovered as a tumour suppressor gene. Later findings have suggested that WT1 also can be oncogenic. This complexity is partly explained by the fact that WT1 has a number of target genes. METHOD: WT1 and its target gene human telomerase reverse transcriptase (hTERT) were analysed in clear cell renal cell carcinoma (ccRCC). In vitro experiments were performed to examine the functional link between WT1 and hTERT by overexpression of WT1 isoforms in the ccRCC cell line, TK-10. RESULTS: WT1 demonstrated lower RNA expression in ccRCC compared with renal cortical tissue, whereas hTERT was increased, showing a negative correlation between WT1 and hTERT (P=0.005). These findings were experimentally confirmed in vitro. The WT1 generated effect on hTERT promoter activity seemed complex, as several negative regulators of hTERT transcription, such as SMAD3, JUN (AP-1) and ETS1, were activated by WT1 overexpression. Downregulation of potential positive hTERT regulators, such as cMyc, AP-2α, AP-2γ, IRF1, NFX1 and GM-CSF, were also observed. Chromatin immunoprecipitation analysis verified WT1 binding to the hTERT, cMyc and SMAD3 promoters. CONCLUSION: The collected data strongly indicate multiple pathways for hTERT regulation by WT1 in ccRCC.


Assuntos
Carcinoma de Células Renais/genética , Neoplasias Renais/genética , Telomerase/genética , Telomerase/metabolismo , Proteínas WT1/fisiologia , Carcinoma de Células Renais/enzimologia , Linhagem Celular Tumoral , Regulação para Baixo , Ativação Enzimática , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Genes myc , Humanos , Neoplasias Renais/enzimologia , Regiões Promotoras Genéticas , Ligação Proteica , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Transfecção , Proteínas WT1/genética , Proteínas WT1/metabolismo
8.
Scand J Public Health ; 36(7): 744-52, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18647789

RESUMO

BACKGROUND: The rate of biological ageing is individual and represents the steady decrease in physiological and mental functions. Adverse social factors have been shown to influence this process. Self-perceived early ageing (SEA) might be a useful indicator of early biological ageing and increased mortality risk. The aim of this population-based study was to identify markers of SEA, including telomere length. METHODS: We studied 1502 subjects (744 men, 758 women) from Northern Sweden. These subjects underwent a physical examination, blood sampling (including telomere length) and completed a self-administered questionnaire about their subjective age, social situation, lifestyle, and self-rated health (SRH). Age- and SRH-adjusted statistical analyses were made comparing SEA subjects with same-sex controls. RESULTS: In all, 7.9% of men and 12.1% of women reported SEA. These subjects had significantly (p<0.0001) wider waist circumference and higher body mass index than controls. SEA men showed higher fasting glucose and SEA women showed higher total cholesterol levels than controls (p=0.020 and p=0.015, respectively). In addition, SEA women more often reported infrequent physical exercise (p=0.006), mental problems (p=0.064) and worse SRH (p=0.001) than controls. In a random sub-sample, telomere length was significantly shorter in SEA subjects (n=139) than controls (n=301; p=0.02), but not after full adjustment for BMI. CONCLUSIONS: Self-perceived early ageing is not uncommon and is associated with abdominal obesity, poor self-rated health, lower education, and shorter telomere length. This could link adverse social factors with features of the metabolic syndrome as well as with early biological ageing, of importance for targeting preventive programmes.


Assuntos
Envelhecimento , Obesidade , Telômero , Envelhecimento/fisiologia , Envelhecimento/psicologia , Índice de Massa Corporal , Senescência Celular/fisiologia , Estudos Transversais , Feminino , Humanos , Expectativa de Vida , Estilo de Vida , Masculino , Síndrome Metabólica/prevenção & controle , Obesidade/prevenção & controle , Fatores de Risco , Autoimagem , Fumar/efeitos adversos , Fatores Socioeconômicos , Inquéritos e Questionários , Suécia/epidemiologia , Telômero/fisiologia , Relação Cintura-Quadril
9.
Leukemia ; 22(2): 339-43, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18046447

RESUMO

The (-938C>A) polymorphism in the promoter region of the BCL-2 gene was recently associated with inferior time to treatment and overall survival in B-cell chronic lymphocytic leukemia (CLL) patients displaying the -938A/A genotype and may thus serve as an unfavorable genetic marker in CLL. Furthermore, the -938A/A genotype was associated with increased expression of Bcl-2. To investigate this further, we analyzed the -938 genotypes of the BCL-2 gene in 268 CLL patients and correlated data with treatment status, overall survival and known prognostic factors, for example, Binet stage, immunoglobulin heavy-chain variable (IGHV) mutational status and CD38 expression. In contrast to the recent report, the current cohort of CLL patients showed no differences either in time to treatment or overall survival in relation to usage of a particular genotype. In addition, no correlation was evident between the (-938C>A) genotypes and IGHV mutational status, Binet stage or CD38. Furthermore, the polymorphism did not appear to affect the Bcl-2 expression at the RNA level. Taken together, our data do not support the use of the (-938C>A) BCL-2 polymorphism as a prognostic marker in CLL and argue against its postulated role in modulating Bcl-2 levels.


Assuntos
Genes bcl-2/genética , Leucemia Linfocítica Crônica de Células B/diagnóstico , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas/genética , Idoso , Biomarcadores , Análise Mutacional de DNA , Genótipo , Humanos , Leucemia Linfocítica Crônica de Células B/genética , Leucemia Linfocítica Crônica de Células B/mortalidade , Pessoa de Meia-Idade , Epidemiologia Molecular , Prognóstico , RNA Mensageiro/análise , Análise de Sobrevida , Resultado do Tratamento
10.
Leukemia ; 22(3): 504-10, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18094715

RESUMO

We retrospectively evaluated reticulin fiber density (RFD) in 166 diagnostic bone marrow (BM) biopsies and 62 biopsies obtained at treatment day 29 from children with acute lymphoblastic leukemia (ALL). Patients with B-cell precursor (BCP)-ALL showed higher RFD as compared to patients with T-cell ALL (P<0.001). RFD correlated negatively with white blood cell count (P=0.008) in BCP-ALL patients. Patients with high-hyperdiploid ALL (51-61 chromosomes), no high-risk criteria and low RFD showed a favorable outcome when compared to similar patients with high RFD (P=0.002). In BCP-ALL patients, RFD at diagnosis correlated to the levels of minimal residual disease (MRD) analyzed by flow cytometry on treatment day 29 (P=0.001). Accordingly, patients with MRD > or = 10(-4) presented higher RFD at diagnosis compared to patients with MRD < 10(-4) (P=0.003). BCP-ALL patients with low RFD at diagnosis and a rapid reduction of RFD on day 29 had a favorable outcome compared to patients with the same baseline RFD level at diagnosis but a slow RFD reduction (P=0.041). To our knowledge, these findings are novel and may indicate BM fibrosis as a new valuable prognostic marker in childhood ALL. Expanded use of BM biopsy both at diagnosis and during follow-up is suggested.


Assuntos
Exame de Medula Óssea , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Mielofibrose Primária/patologia , Reticulina/análise , Adolescente , Aneuploidia , Biópsia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Leucemia-Linfoma de Células T do Adulto/patologia , Leucemia-Linfoma de Células T do Adulto/terapia , Masculino , Neoplasia Residual , Leucemia-Linfoma Linfoblástico de Células Precursoras B/patologia , Leucemia-Linfoma Linfoblástico de Células Precursoras B/terapia , Leucemia-Linfoma Linfoblástico de Células Precursoras/classificação , Leucemia-Linfoma Linfoblástico de Células Precursoras/complicações , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidade , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Mielofibrose Primária/etiologia , Prognóstico , Estudos Retrospectivos , Medição de Risco , Análise de Sobrevida , Suécia/epidemiologia , Resultado do Tratamento
11.
Leukemia ; 20(1): 77-81, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16307023

RESUMO

The G(-248)A polymorphism in the promoter region of the Bax gene was recently associated with low Bax expression, more advanced stage, treatment resistance and short overall survival in B-cell chronic lymphocytic leukemia (CLL), the latter particularly in treated patients. To investigate this further, we analyzed 463 CLL patients regarding the presence or absence of the G(-248)A polymorphism and correlated with overall survival, treatment status and known prognostic factors, for example, Binet stage, VH mutation status and genomic aberrations. In this material, similar allele and genotype frequencies of the Bax polymorphism were demonstrated in CLL patients and controls (n=207), where 19 and 21% carried this polymorphism, respectively, and no skewed distribution of the polymorphism was evident between different Binet stages and VH mutated and unmutated CLLs. Furthermore, no difference in overall survival was shown between patients displaying the G(-248)A polymorphism or not (median survival 85 and 102 months, respectively, P=0.21), and the polymorphism did not influence outcome specifically in treated CLL. Neither did the polymorphism affect outcome in prognostic subsets defined by VH mutation status or genomic aberrations. In conclusion, the pathogenic role and clinical impact of the Bax polymorphism is limited in CLL.


Assuntos
Biomarcadores Tumorais/genética , Leucemia Linfocítica Crônica de Células B/genética , Polimorfismo Genético/genética , Regiões Promotoras Genéticas , Proteína X Associada a bcl-2/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/biossíntese , Estudos de Coortes , Análise Citogenética , Feminino , Humanos , Leucemia Linfocítica Crônica de Células B/diagnóstico , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida , Proteína X Associada a bcl-2/biossíntese
14.
Br J Cancer ; 88(9): 1417-23, 2003 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-12778072

RESUMO

Aberrations in the G1/S transition of the cell cycle have been observed in many malignancies and seem to be critical in the transformation process. Few studies have delineated the presence of G1/S regulatory defects and their clinical relevance in renal cell carcinoma (RCC). Therefore, we have examined the protein contents of cyclin D1, D3, E, and p27 in 218 RCCs, using tissue microarray and immunohistochemistry. The results from a subset of tumours were confirmed by Western blotting and immunohistochemical staining of regular tissue sections. Interestingly, low protein contents of cyclin D1 and p27 were associated with high nuclear grade, large tumour size, and poor prognosis for patients with conventional tumours. We further observed substantial differences in the pattern of G1/S regulatory defects between the different RCC subtypes. The majority of both conventional and papillary cases expressed p27; however, chromophobe tumours generally lacked p27 staining. In addition, conventional RCCs often expressed high cyclin D1 protein levels, while papillary RCCs exhibited high cyclin E. In summary, we have shown that G1/S regulatory defects are present in RCC and are associated with clinico-pathological parameters. The pattern of cell cycle regulatory defects also differed between RCC subtypes.


Assuntos
Carcinoma de Células Renais/genética , Ciclina D1/genética , Ciclina E/genética , Ciclinas/genética , Neoplasias Renais/genética , Proteínas dos Microfilamentos/genética , Proteínas Musculares , Análise Atuarial , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Renais/mortalidade , Carcinoma de Células Renais/patologia , Ciclo Celular/genética , Ciclina D , Ciclina D1/metabolismo , Ciclina E/metabolismo , Ciclinas/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Neoplasias Renais/mortalidade , Neoplasias Renais/patologia , Masculino , Proteínas dos Microfilamentos/metabolismo , Pessoa de Meia-Idade , Análise Multivariada , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Análise de Sobrevida , Fatores de Tempo
15.
Int J Oncol ; 22(4): 861-8, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12632080

RESUMO

A group of 133 primary oral squamous cell carcinomas were studied concerning a relationship between exposure factors and tumour biological parameters with a focus on the TP53 gene and p53 protein status. Tumours were evaluated using immunohistochemistry (IHC) for expression of p53, PCNA, Ki-67 and bcl-2 proteins. The TP53 gene was studied for mutations using PCR amplification of exons 5-9 and single strand conformation polymorphism (SSCP) analysis. The collected data were correlated to the exposure factors smoking, oral snuff, liquor, oral infections, dental factors, dental X-ray and iron deficiency. When compared with matched controls only oral infections, and reported HSV-infections in particular, gave statistically significant ORs (odds ratio) for all tumours (OR 8.0) as well as for the group of IHC p53 positive tumours (OR 12). No association between smoking and p53 positivity was found (OR 1.0).


Assuntos
Antígeno Ki-67/biossíntese , Neoplasias Bucais/genética , Neoplasias Bucais/metabolismo , Antígeno Nuclear de Célula em Proliferação/biossíntese , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Proteína Supressora de Tumor p53/biossíntese , Carcinoma de Células Escamosas/epidemiologia , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Estudos de Casos e Controles , Divisão Celular , Linhagem Celular Tumoral , Éxons , Genes p53 , Humanos , Imuno-Histoquímica , Neoplasias Bucais/epidemiologia , Mutação , Razão de Chances , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples , Fatores de Risco , Proteína Supressora de Tumor p53/metabolismo , Raios X
16.
Br J Cancer ; 88(4): 593-8, 2003 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-12592375

RESUMO

The immunoglobulin V(H) gene mutation status can divide B-cell chronic lymphocytic leukaemia (CLL) into two entities with a different clinical course. Cases with unmutated V(H) genes, considered to evolve from pregerminal centre (GC) cells, have a worse outcome compared to cases showing mutated V(H) genes, that is, post-GC derived. Also, telomere length has been reported to be of prognostic significance in CLL. Interestingly, telomerase becomes activated during the GC reaction and an elongation of the telomeres occurs in GC B cells. We performed telomere length and V(H) gene analysis in a series of 61 CLL cases, in order to investigate if the unique telomere lengthening shown in GC B cells could reflect the telomere status in the two subsets of mutated and unmutated CLL. A novel association was found between V(H) gene mutation status and telomere length, since significantly shorter telomeres were demonstrated in the unmutated group compared to the mutated group (mean length 4.3 vs 6.3 kbp). Shorter telomeres also constituted a subgroup with a worse prognosis than cases with longer telomeres (median survival 59 vs 159 months). Furthermore, the Ig gene sequence data revealed that samples with high mutations frequency (>6%) had long telomeres ( approximately 8 kbp). Thus, both the telomere and V(H) gene mutation status in CLL appear linked, which may reflect the proliferative history of the clonal cells with regard to the GC reaction.


Assuntos
Genes de Imunoglobulinas/genética , Leucemia Linfocítica Crônica de Células B/genética , Leucemia Linfocítica Crônica de Células B/patologia , Mutação/genética , Telômero/patologia , Idoso , Aberrações Cromossômicas , Análise Mutacional de DNA , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Análise de Sobrevida , Telômero/genética , Fatores de Tempo
18.
Exp Cell Res ; 271(2): 223-9, 2001 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-11716534

RESUMO

The replication timing of telomeres seems to differ between species. Yeast telomeres are late replicating, whereas limited data from very few human cell lines have indicated telomere replication throughout S phase. In the present study a series of permanent cell lines and patient samples was investigated using a flow cytometric approach for telomere length determination based on in situ hybridization using peptide nucleic acid probes and DNA staining. This method permits selective analysis of cells in specific phases of the cell cycle without perturbation of the cell cycle machinery. The timing of replication of telomeric C(3)TA(2) and T(2)AG(3) repeats was found to differ between individual samples and could precede or be concomitant with the replication of bulk DNA. Replication of the T(2)AG(3) strand seemed to occur somewhat later than that of the C(3)TA(2) strand in some samples. (GTG)(n) and other repetitive sequences generally showed a replication pattern similar to that of the bulk of DNA with slightly individual differences, whereas centromeric DNA repeats consistently replicated within a short time frame in late S phase. The apparent variability in replication timing seen for telomeric DNA might suggest individual differences in firing of replication origins.


Assuntos
Ciclo Celular/genética , Centrômero/genética , Replicação do DNA/fisiologia , Sequências Repetitivas de Ácido Nucleico/fisiologia , Telômero/genética , Citometria de Fluxo , Regulação Neoplásica da Expressão Gênica/fisiologia , Neoplasias Hematológicas/genética , Humanos , Hibridização in Situ Fluorescente , Fase S/genética , Fatores de Tempo , Células Tumorais Cultivadas , Leveduras/genética
20.
Leuk Res ; 25(12): 1033-45, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11684274

RESUMO

Genetic instability has important implications for detection of minimal residual disease (MRD) when the target is a clonal genetic marker revealed at diagnosis. A successful MRD detection approach requires a stable marker and for lymphoid leukemias clonal rearrangements of immunoglobulin (Ig) and T cell receptor (TCR) genes are commonly used. In the present study, Ig heavy chain (IgH) and TCR (gamma and delta) genes were studied in 18 consecutive, relapsing precursor-B ALL patients. At least one clonal rearrangement was found in all cases at presentation (IgH 94%, TCRgamma 39% and TCRdelta 28%). An altered rearrangement pattern between diagnosis and relapse was demonstrated in 14 patients (78%). At least one stable molecular target was found in 13 out of 18 cases (72%). Clonal differences between diagnostic and relapse samples were explained by: (1) loss of original rearrangements; (2) V(H) to DJ(H) joining; (3) V(H) gene replacement; (4) appearance of new rearrangements. In two cases with apparently new IgH gene rearrangements at relapse extended sequencing of the diagnostic samples revealed minor clonal rearrangements identical to the relapse clones. Interestingly, one patient displayed instability on both the IgH and TCR gene loci, whereas a stable Igkappa rearrangement was found at presentation and relapse. These data show that clonal diversity is common in precursor-B ALL and strongly suggest that MRD detection should include multiple gene targets to minimize false-negative samples. Even so, five of our 18 relapse cases (28%) lacked stable clonal markers and should have been unsuitable for MRD detection.


Assuntos
Rearranjo Gênico , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genética , Adulto , Idoso , Sequência de Bases , Criança , Pré-Escolar , Rearranjo Gênico do Linfócito T , Genes de Imunoglobulinas , Humanos , Cadeias Pesadas de Imunoglobulinas/genética , Pessoa de Meia-Idade , Dados de Sequência Molecular , Neoplasia Residual , Reação em Cadeia da Polimerase , Leucemia-Linfoma Linfoblástico de Células Precursoras B/diagnóstico
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