RESUMO
BACKGROUND: Germline variant evaluation in precision oncology opens new paths toward the identification of patients with genetic tumor risk syndromes and the exploration of therapeutic relevance. Here, we present the results of germline variant analysis and their clinical implications in a precision oncology study for patients with predominantly rare cancers. PATIENTS AND METHODS: Matched tumor and control genome/exome and RNA sequencing was carried out for 1485 patients with rare cancers (79%) and/or young adults (77% younger than 51 years) in the National Center for Tumor Diseases/German Cancer Consortium (NCT/DKTK) Molecularly Aided Stratification for Tumor Eradication Research (MASTER) trial, a German multicenter, prospective, observational precision oncology study. Clinical and therapeutic relevance of prospective pathogenic germline variant (PGV) evaluation was analyzed and compared to other precision oncology studies. RESULTS: Ten percent of patients (n = 157) harbored PGVs in 35 genes associated with autosomal dominant cancer predisposition, whereof up to 75% were unknown before study participation. Another 5% of patients (n = 75) were heterozygous carriers for recessive genetic tumor risk syndromes. Particularly, high PGV yields were found in patients with gastrointestinal stromal tumors (GISTs) (28%, n = 11/40), and more specifically in wild-type GISTs (50%, n = 10/20), leiomyosarcomas (21%, n = 19/89), and hepatopancreaticobiliary cancers (16%, n = 16/97). Forty-five percent of PGVs (n = 100/221) supported treatment recommendations, and its implementation led to a clinical benefit in 40% of patients (n = 10/25). A comparison of different precision oncology studies revealed variable PGV yields and considerable differences in germline variant analysis workflows. We therefore propose a detailed workflow for germline variant evaluation. CONCLUSIONS: Genetic germline testing in patients with rare cancers can identify the very first patient in a hereditary cancer family and can lead to clinical benefit in a broad range of entities. Its routine implementation in precision oncology accompanied by the harmonization of germline variant evaluation workflows will increase clinical benefit and boost research.
Assuntos
Neoplasias , Adulto Jovem , Humanos , Neoplasias/diagnóstico , Neoplasias/genética , Neoplasias/terapia , Mutação em Linhagem Germinativa , Predisposição Genética para Doença , Estudos Prospectivos , Síndrome , Medicina de Precisão/métodosRESUMO
BACKGROUND: Extracorporeal life-support systems are valuable tools to treat patients with acute cardiopulmonary failure in intensive care facilities, and are highly suitable for the interhospital transfer of critically ill patients to specialized centers. This article reviews the cannulation strategies and associated vascular complications in our institution. METHODS: Between January 2004 and December 2009, 464 extracorporeal life-support systems were implanted via percutaneous cannulation at our institution. The type and incidence of adverse events related to the percutaneous access to femoral, subclavian vessels and the jugular vein were retrospectively analyzed. The primary focus was on bleeding and limb ischemia. RESULTS: 464 patients (340 male, 124 female) with isolated pulmonary or combined cardiopulmonary failure were connected to extracorporeal gas exchange systems. Most patients (n = 196) were connected to a PECLA system; 158 patients to a veno-arterial ECMO. Use of a veno-venous ECMO system was necessary in 110 cases. Thirty-two patients (6.9 %) suffered bleeding complications after cannula insertion, predominantly after PECLA placement (3.9 %). After implantation, limb ischemia developed in 15 cases (3.2 %), mostly in the veno-arterial ECMO group (n = 13). Demographic data and cannula size show no significant difference between patient groups with and without ischemic complications ( P = 0.57). A prophylactic fasciotomy was performed in the 15 cases with limb ischemia. Survival was independent of ischemic (leg) complications. CONCLUSION: With proper vessel visualization, exposure and cannulation, and accurate cannula placement, optimal flows and minimal complication rates can be achieved, rendering percutaneous extracorporeal life support a safe procedure.
Assuntos
Cateterismo Periférico , Circulação Extracorpórea , Cuidados para Prolongar a Vida/métodos , Adolescente , Adulto , Idoso , Cateterismo Periférico/efeitos adversos , Cateterismo Periférico/mortalidade , Distribuição de Qui-Quadrado , Desenho de Equipamento , Circulação Extracorpórea/efeitos adversos , Circulação Extracorpórea/instrumentação , Circulação Extracorpórea/mortalidade , Extremidades/irrigação sanguínea , Feminino , Alemanha , Hemorragia/etiologia , Humanos , Isquemia/etiologia , Isquemia/cirurgia , Cuidados para Prolongar a Vida/instrumentação , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Análise de Sobrevida , Taxa de Sobrevida , Fatores de Tempo , Resultado do Tratamento , Adulto JovemRESUMO
Since the activity of several conventional anticancer drugs is restricted by resistance mechanisms and dose-limiting side-effects, the design of nanocarriers seems to be an efficient and promising approach for drug delivery. Their chemical and mechanical stability and their possible multifunctionality render tubular nanomaterials, such as carbon nanotubes (CNTs) and carbon nanofibres (CNFs), promising delivery agents for anticancer drugs. The goal of the present study was to investigate CNTs and CNFs in order to deliver carboplatin in vitro. No significant intrinsic toxicity of unloaded materials was found, confirming their biocompatibility. Carboplatin was loaded onto CNTs and CNFs, revealing a loading yield of 0.20 mg (CNT-CP) and 0.13 mg (CNF-CP) platinum per milligram of material. The platinum release depended on the carrier material. Whereas CNF-CP marginally released the drug, CNT-CP functioned as a drug depot, constantly releasing up to 68% within 14 days. The cytotoxicity of CNT-CP and CNF-CP in urological tumour cell lines was dependent on the drug release. CNT-CP was identified to be more effective than CNF-CP concerning the impairment of proliferation and clonogenic survival of tumour cells. Moreover, carboplatin, which was delivered by CNT-CP, exhibited a higher anticancer activity than free carboplatin.
Assuntos
Apoptose/efeitos dos fármacos , Carboplatina/farmacocinética , Proliferação de Células/efeitos dos fármacos , Sistemas de Liberação de Medicamentos/métodos , Nanotubos de Carbono/química , Carboplatina/química , Carboplatina/farmacologia , Linhagem Celular Tumoral , Preparações de Ação Retardada , Ensaios de Seleção de Medicamentos Antitumorais , Estabilidade de Medicamentos , Humanos , Teste de Materiais , Nanofibras/química , Nanofibras/ultraestrutura , Nanotubos de Carbono/ultraestrutura , Neoplasias/tratamento farmacológico , Ensaio Tumoral de Célula-TroncoRESUMO
Common fragile sites are specific regions of the genome that form gaps and breaks on metaphase chromosomes when DNA synthesis is partially inhibited. Fragile sites and their associated genes show frequent deletions and other rearrangements in cancer cells, and may be indicators of DNA replication stress early in tumorigenesis. We have previously shown that the DNA damage response proteins ATR, BRCA1 and FANCD2 play critical roles in maintaining the stability of fragile site regions. To further elucidate the pathways regulating fragile site stability, we have investigated the effects of depletion of the cell cycle checkpoint kinases, CHK1 and CHK2 on common fragile site stability in human cells. We demonstrate that both CHK1 and CHK2 are activated following treatment of cells with low doses of aphidicolin that induce fragile site breakage. Furthermore, we show that depletion of CHK1, but not CHK2, using short-interfering RNA (siRNA) leads to highly destabilized chromosomes and specific common fragile site breakage. In many cells, CHK1 depletion resulted in extensive chromosome fragmentation, which was distinct from endonucleolytic cleavage commonly associated with apoptosis. These findings demonstrate a critical role for the CHK1 kinase in regulating chromosome stability, and in particular, common fragile site stability.
Assuntos
Quebra Cromossômica , Sítios Frágeis do Cromossomo , Proteínas Quinases/deficiência , Proteínas Quinases/genética , Proteínas Serina-Treonina Quinases/fisiologia , Células Cultivadas , Quinase 1 do Ponto de Checagem , Quinase do Ponto de Checagem 2 , Células HCT116 , Células HeLa , Humanos , Proteínas Quinases/fisiologia , Proteínas Serina-Treonina Quinases/deficiência , Proteínas Serina-Treonina Quinases/genéticaRESUMO
Overexpression of matrix metalloproteinases (MMPs) facilitates tumor cell invasion. Synthetic MMP inhibitors such as batimastat have been designed to treat cancer. We report that because of batimastat treatment, human breast carcinoma cells metastasized to the liver in nude mice and that an increase of liver metastases of murine T-cell lymphoma cells was observed in syngeneic mice. Batimastat treatment also caused liver-specific overexpression of MMPs-2, -9, and mRNA up-regulation of angiogenesis factors and caspase-1, even in tumor-free animals. Induction of organ-specific side effects need to be taken into account regarding further development and clinical use of synthetic MMP inhibitors.
Assuntos
Antineoplásicos/toxicidade , Neoplasias Hepáticas Experimentais/induzido quimicamente , Neoplasias Hepáticas Experimentais/secundário , Fenilalanina/análogos & derivados , Fenilalanina/toxicidade , Inibidores de Proteases/toxicidade , Tiofenos/toxicidade , Indutores da Angiogênese/biossíntese , Indutores da Angiogênese/genética , Animais , Caspase 1/biossíntese , Caspase 1/genética , Feminino , Humanos , Fígado/efeitos dos fármacos , Fígado/enzimologia , Neoplasias Hepáticas Experimentais/enzimologia , Neoplasias Pulmonares/induzido quimicamente , Neoplasias Pulmonares/enzimologia , Neoplasias Pulmonares/secundário , Linfoma de Células T/enzimologia , Linfoma de Células T/patologia , Neoplasias Mamárias Experimentais/enzimologia , Neoplasias Mamárias Experimentais/patologia , Metaloproteinase 2 da Matriz/biossíntese , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 9 da Matriz/biossíntese , Metaloproteinase 9 da Matriz/genética , Inibidores de Metaloproteinases de Matriz , Camundongos , Camundongos Endogâmicos DBA , Camundongos Nus , Transplante de Neoplasias , Análise de Sequência com Séries de Oligonucleotídeos , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Regulação para Cima/efeitos dos fármacosRESUMO
Little is known about the treatment of bone pain in animal models of bone cancer. In the present study, the orthotopic 143-B human osteosarcoma xenotransplantation model was used to address the following questions: (1) Can repetitive analgesic treatment extend the experimental period by prolonging the time to reach humane endpoints and (2) Does repetitive analgesic treatment affect bone tumour development and metastasis? The analgesics, buprenorphine and meloxicam, were either applied individually or in combination at 12 h intervals as soon as the animals began to avoid using the tumour cell injected leg. While control mice treated with NaCl showed continuous body weight loss, the major criterion previously for terminating the experiments, animals treated with analgesic substances did not. The control mice had to be sacrificed 26 days after tumour cell injection, whereas the groups of animals with the different pain treatments were euthanized after an additional eight days. Importantly, primary intratibial tumour growth was not affected in any of the experimental groups by any of the pain treatment procedures. Between days 26 and 34 after tumour cell injection an increase of about 100% of the number of lung metastases was found for the groups treated with buprenorphine alone or together with meloxicam, but not for the group treated with meloxicam alone. In summary, the results indicated that both buprenorphine and meloxicam are suitable analgesics for prolonging the experimental periods in an experimental intratibial osteosarcoma mouse model.
Assuntos
Analgésicos Opioides/administração & dosagem , Bem-Estar do Animal , Anti-Inflamatórios não Esteroides/administração & dosagem , Buprenorfina/administração & dosagem , Camundongos SCID/fisiologia , Manejo da Dor , Tiazinas/administração & dosagem , Tiazóis/administração & dosagem , Animais , Neoplasias Ósseas/patologia , Modelos Animais de Doenças , Quimioterapia Combinada , Feminino , Injeções , Longevidade/efeitos dos fármacos , Neoplasias Pulmonares/secundário , Meloxicam , Camundongos , Osteossarcoma/patologia , TíbiaRESUMO
The Sox gene family encodes an important group of transcription factors harboring the conserved high-mobility group (HMG) box originally identified in the mouse and human testis determining gene Sry. We have cloned and sequenced SOX6, a member of the human Sox gene family. SOX6 cDNAs isolated from a human myoblast cDNA library show 94.3% amino acid identity to mouse Sox6 throughout the gene, and 100% identity in the critical HMG box and coiled-coil domains. The human SOX6 gene was localized to chromosome 11p15.2-11p15.3 in a region of shared synteny with distal mouse chromosome 7. An analysis of the genomic structure of the human SOX6 gene revealed 16 exons. We identified three SOX6 cDNAs that are generated by alternative splicing. Northern blot analysis revealed that SOX6 is expressed in a wide variety of tissues, most abundantly in skeletal muscle, suggesting an important role for SOX6 in muscle. Mice homozygous for a null mutation of Sox6 (p(100H)) die suddenly within the first 2 weeks after birth, most likely from cardiac conduction defects (Hagiwara et al., 2000). Thus, there is a possibility that human SOX6 is similarly involved in an, as yet, unidentified human cardiac disorder.
Assuntos
Proteínas de Ligação a DNA/genética , Genes/genética , Proteínas de Grupo de Alta Mobilidade/genética , Fatores de Transcrição , Sequência de Aminoácidos , Sequência de Bases , Northern Blotting , Bandeamento Cromossômico , Mapeamento Cromossômico , Cromossomos Humanos Par 11/genética , Clonagem Molecular , DNA/química , DNA/genética , DNA Complementar/química , DNA Complementar/genética , Éxons , Feminino , Expressão Gênica , Humanos , Íntrons , Masculino , Dados de Sequência Molecular , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fatores de Transcrição SOXD , Alinhamento de Sequência , Análise de Sequência de DNA , Distribuição TecidualRESUMO
Aphidicolin-induced common fragile sites are site-specific gaps or breaks seen on metaphase chromosomes after partial inhibition of DNA synthesis. These fragile sites were first recognized during the early studies of the fragile X syndrome and are induced by the same conditions of folate or thymidylate stress used to induce the fragile X site. Common fragile sites are normally stable in cultured human cells. However, following induction with replication inhibitors, they display a number of characteristics of unstable and highly recombinogenic DNA. From the many studies that have cloned and characterized fragile sites, it is now known that these sites extend over large regions, are associated with genes, exhibit late or delayed replication, and contain regions of high flexibility but are otherwise unremarkable in sequence. Studies showing that fragile sites and their associated genes are frequently deleted or rearranged in cancer cells have clearly demonstrated their importance in genome instability in tumorigenesis. Yet until recently, very little was known about the molecular mechanisms involved in their stability. Recent findings showing that the key checkpoint genes ATR and BRCA1 are critical for genome stability at fragile sites have shed new light on these mechanisms and on the biological significance of common fragile sites.
Assuntos
Sítios Frágeis do Cromossomo/genética , Proteínas Serina-Treonina Quinases , Animais , Afidicolina/farmacologia , Proteínas Mutadas de Ataxia Telangiectasia , Proteína BRCA1/genética , Proteínas de Ciclo Celular/genética , Aberrações Cromossômicas/induzido quimicamente , Cromossomos Humanos Par 16/genética , Cromossomos Humanos Par 3/genética , Evolução Molecular , Humanos , Hibridização in Situ FluorescenteRESUMO
Cyclosporine A (CsA) seems to exert direct effects on blood pressure and diurnal blood pressure alterations. After kidney transplant about 60% of the recipients are suffering from such alterations. In the present study, blood pressure profiles of 15 FK506-treated kidney transplant patients were compared to recipients with CsA immunosuppression. Both groups showed no statistical differences in number, kidney function, age, body weight, sex distribution and time after transplantation. Mean arterial blood pressure in FK506-treated patients at daytime was 105 +/- 2.5 mmHg, at night 109 +/- 3.0 mmHg. Systolic blood pressure difference was 2.3 mmHg, diastolic day/night blood pressure difference 0.6 mmHg, and the difference of the heart frequency 6.8 beats/min. Cyclosporin A-treated patients showed a mean arterial blood pressure during the day of 107 + 2.6 mmHg, at night-time a mean arterial blood pressure of 107 + 3.4 mmHg was measured. The diurnal blood pressure alterations of systolic blood pressure were 0.9 mmHg, diastolic blood pressure difference 3.5 mmHg respectively, the heart frequency showed a difference of 4.4 beats/min. Both, FK506-treated patients and patients with CsA immunosuppression exhibit reduced diurnal blood pressure alterations. Furthermore, mean arterial pressure in both, FK506 and CsA-treated patients was elevated and showed no statistical differences between the groups. In FK506-treated patients, however, antihypertensive therapy was less intensive. Concerning arterial blood pressure and diurnal blood pressure alterations, FK506 offers no advantages as compared to cyclosporine A. The reduced usage of antihypertensive drugs, however, may give evidence for lower hypertensive properties of FK506 as compared to CsA.
Assuntos
Monitorização Ambulatorial da Pressão Arterial , Pressão Sanguínea/efeitos dos fármacos , Ciclosporina/uso terapêutico , Rejeição de Enxerto/prevenção & controle , Imunossupressores/uso terapêutico , Transplante de Rim/efeitos adversos , Tacrolimo/uso terapêutico , Adulto , Anti-Hipertensivos/uso terapêutico , Nitrogênio da Ureia Sanguínea , Creatinina/sangue , Rejeição de Enxerto/metabolismo , Rejeição de Enxerto/fisiopatologia , Humanos , Hipertensão/tratamento farmacológico , Hipertensão/etiologia , Pessoa de Meia-Idade , Ácido Úrico/sangueRESUMO
We report the use of out-of-hospital extracorporeal life support (ECLS) in cardiac arrest. We treated a 9-year-old girl with cardiac arrest after warm-water drowning with percutaneous venoarterial extracorporeal membrane oxygenation (ECMO) using a new portable Mini-ECMO system. A beating-heart circulation was reestablished on ECMO, but, unfortunately, our patient did not survive. This case shows that Mini-ECMO support can be used to restore an effective circulation and gas exchange in the out-of-hospital setting.
Assuntos
Reanimação Cardiopulmonar/métodos , Afogamento , Serviços Médicos de Emergência/métodos , Oxigenação por Membrana Extracorpórea/métodos , Parada Cardíaca Extra-Hospitalar/terapia , Criança , Evolução Fatal , Feminino , Humanos , Parada Cardíaca Extra-Hospitalar/etiologia , Medição de RiscoAssuntos
Proteínas de Transporte/genética , Repetições de Dinucleotídeos , Genes Supressores de Tumor , Proteína P2 de Mielina/genética , Proteínas de Neoplasias , Proteínas Supressoras de Tumor , Alelos , Proteína 3 Ligante de Ácido Graxo , Proteína 7 de Ligação a Ácidos Graxos , Proteínas de Ligação a Ácido Graxo , Humanos , ÍntronsAssuntos
Antígenos CD/sangue , Rejeição de Enxerto/diagnóstico , Transplante de Rim/imunologia , Antígenos Comuns de Leucócito/sangue , Linfócitos T Auxiliares-Indutores/imunologia , Antígenos CD4/sangue , Citometria de Fluxo/métodos , Rejeição de Enxerto/sangue , Rejeição de Enxerto/imunologia , Humanos , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade , Estatísticas não Paramétricas , Subpopulações de Linfócitos T/imunologiaRESUMO
Massive pulmonary embolism (PE) leads to cardiogenic shock and is associated with mortality rates of up to 75%. We report on a 27-year-old mother in childbirth who developed a massive post-partal PE and cardiac arrest. Despite mechanical resuscitation, return of spontaneous circulation (ROSC) could not be achieved. After systemic thrombolysis, ROSC returned, but cardiopulmonary failure was persisting, complicated by massive bleeding shock. By using a newly developed, hand-held ECMO system, systemic blood flow and oxygenation were restored and emergency medical services for advanced surgical treatment (hysterectomy and pulmonary embolectomy) were possible. The patient recovered completely. We assume that this newly developed hand-held ECMO device enables rapid onset mechanical life support and improves the prognosis of patients in fatal conditions.
Assuntos
Cesárea/efeitos adversos , Oxigenação por Membrana Extracorpórea/instrumentação , Parada Cardíaca/cirurgia , Embolia Pulmonar/etiologia , Embolia Pulmonar/cirurgia , Terapia Trombolítica , Adulto , Embolectomia , Oxigenação por Membrana Extracorpórea/métodos , Feminino , Parada Cardíaca/etiologia , Hemorragia/complicações , Hemorragia/etiologia , Hemorragia/cirurgia , Humanos , Histerectomia , GravidezRESUMO
L1 cell adhesion molecule (L1-CAM) is a transmembrane cell adhesion molecule involved in cell migration and axon guidance in the developing nervous system. L1 is also overexpressed in ovarian and endometrial carcinomas and is associated with a bad prognosis. In carcinoma cell lines, L1 overexpression augments cell motility, tumor growth in mice and induces expression of Erk-dependent genes. Here, we show that a mutation in the cytoplasmic portion of L1 (T1247A, S1248A) abrogates Erk activation, blocks cell migration on extracellular matrix proteins and did not augment tumor growth in non-obese diabetic/severe combined immuno-deficient mice. In cells expressing mutant L1, the induction of Erk-dependent genes such as beta3-integrin, cathepsin-B and several transcription factors is eliminated and the invasive phenotype is abrogated. L1 antibodies showed similar effects. They prevented Erk activation and interfered with the Erk-dependent gene expression pattern. These findings provide a rationale for the mode of action of L1 antibodies and suggest that interference with L1 function could become a valuable target for therapy.
Assuntos
Anticorpos Monoclonais/uso terapêutico , Proliferação de Células , Citoplasma/fisiologia , Regulação Neoplásica da Expressão Gênica , Neoplasias/imunologia , Neoplasias/terapia , Molécula L1 de Adesão de Célula Nervosa/fisiologia , Animais , Linhagem Celular , Linhagem Celular Tumoral , Citoplasma/química , Feminino , Regulação Neoplásica da Expressão Gênica/imunologia , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Invasividade Neoplásica , Neoplasias/genética , Neoplasias/patologia , Neoplasias Experimentais/genética , Neoplasias Experimentais/imunologia , Neoplasias Experimentais/patologia , Neoplasias Experimentais/terapia , Molécula L1 de Adesão de Célula Nervosa/química , Estrutura Terciária de ProteínaRESUMO
After allogenic transplantations a dramatic increase in the development of arteriosclerotic plaques can be observed, which might be due to metabolic alterations, influenced by changes of the transplant organ or immunosuppression. In this study the effects of FK 506 in kidney transplant patients on cardiovascular risk factors were compared to cyclosporin A (CsA) immunosuppression. Both groups showed no statistical differences in number, kidney function, age, body weight, sex distribution, steroid dosage and follow-up time after transplantation. Total cholesterol was similar in FK 506-treated patients (231 +/- 22 vs. 278 +/- 52 mg/dl) as compared with patients with CsA immunosuppression. Furthermore, there were no differences in triglycerides (220 +/- 72 vs. 210 +/- 67 mg/dl), HDL-cholesterol (67 +/- 14 vs. 52 +/- 18 mg/dl) and fasting glucose (112 +/- 36 vs. 116 +/- 17 mg/dl). However, the concentration of LDL-cholesterol (114 +/- 21 vs. 167 +/- 37 mg/dl), the independent risk factor Lp(a) (11 +/- 9 vs. 27 +/- 8 mg/dl) and fibrinogen (216 +/- 71 vs. 297 +/- 47) was lower in FK 506-treated patients. Our results indicate that FK 506 immunosuppression offers some advantages in cardiovascular risk factors.
Assuntos
Ciclosporina/uso terapêutico , Fibrinogênio/efeitos dos fármacos , Imunossupressores/uso terapêutico , Transplante de Rim , Metabolismo dos Lipídeos , Tacrolimo/uso terapêutico , Adulto , Fatores Etários , Arteriosclerose/etiologia , Glicemia/análise , Peso Corporal , Colesterol/sangue , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Ciclosporina/administração & dosagem , Jejum , Feminino , Fibrinogênio/análise , Seguimentos , Glucocorticoides/administração & dosagem , Glucocorticoides/uso terapêutico , Humanos , Imunossupressores/administração & dosagem , Transplante de Rim/fisiologia , Lipídeos/sangue , Masculino , Prednisolona/administração & dosagem , Prednisolona/uso terapêutico , Fatores de Risco , Fatores Sexuais , Tacrolimo/administração & dosagem , Transplante Homólogo , Triglicerídeos/sangueRESUMO
The genetic events associated with endometrial cancer are at present poorly understood. Frequent loss of heterozygosity (LOH) in a particular chromosomal region is often indicative of the involvement of a tumor suppressor gene. Previous studies are in disagreement over the involvement of a tumor suppressor gene(s) on the short arm of chromosome 3 in endometrial tumorigenesis. A set of 75 endometrial carcinomas was examined for the presence of LOH using 10 microsatellite repeat polymorphisms which are localized to chromosome 3p. In addition, these tumors were examined for the presence of replication errors (RER). Eleven of the 64 RER-negative tumors (17.2%) displayed LOH at one or more loci on chromosome 3p. The highest frequency of LOH at a single marker was 10.8% (4/37) at the locus D3S1312. The tumors investigated did not suggest that there was any common region of deletion. There was a significant increase in the frequency of 3p LOH in high-grade versus low-grade endometrioid adenocarcinomas (P < 0.05). Our results indicate that it is unlikely that a tumor suppressor gene on the short arm of chromosome 3 plays a major role in endometrial tumorigenesis.
Assuntos
Carcinoma Endometrioide/genética , Cromossomos Humanos Par 3 , Neoplasias do Endométrio/genética , Heterozigoto , Alelos , Autorradiografia , Sequência de Bases , Carcinoma Endometrioide/patologia , DNA de Neoplasias/genética , Neoplasias do Endométrio/patologia , Feminino , Humanos , Repetições de Microssatélites , Sondas Moleculares/genética , Dados de Sequência Molecular , Polimorfismo GenéticoRESUMO
OBJECTIVE: The goal of this study was to assess the involvement of chromosome 1p deletion in ovarian papillary serous carcinoma (OPSC) via high-resolution physical mapping to detect a candidate tumor suppressor gene previously implicated in uterine papillary serous carcinoma (UPSC) tumorigenesis. METHODS: Previous studies have demonstrated a high rate of loss of heterozygosity (LOH) within a critical region of chromosome 1p in UPSC, suggesting the presence of a putative tumor suppressor gene important in the development of UPSC. To compare the genetic changes in OPSC with those in UPSC, seven microsatellite repeat polymorphisms were used to evaluate LOH in primary OPSC specimens. Allelic intensity was compared between normal and tumor DNA from microdissected, formalin-fixed, paraffin-embedded specimens. In addition to the same seven 1p markers used for UPSC, three additional non-1p markers for chromosomes 1q, 11q, and 2p were tested to determine a baseline rate of LOH. RESULTS: Overall, 26.6% (8/30) of OPSC (vs 63.2% of UPSC) were characterized by loss at either of the two loci that define the critical region for UPSC. Rates of LOH at each of the 1p loci in the OPSC tumors ranged from 5.6 to 38.9%, which are compatible with background rates of loss for OPSC. LOH at non-1p loci was 29.2%. CONCLUSION: While a tumor suppressor gene on 1p appears to be an important genetic event in the development of UPSC, a similar rate and pattern of loss on 1p are not identified in OPSC. Thus, despite the striking clinical similarities between UPSC and OPSC, tumorigenesis in these carcinomas appears to occur via distinctly different pathways.
Assuntos
Deleção Cromossômica , Cromossomos Humanos Par 1/genética , Cistadenocarcinoma Papilar/genética , Neoplasias Ovarianas/genética , Neoplasias Uterinas/genética , Primers do DNA/química , Feminino , Genes Supressores de Tumor , Humanos , Perda de Heterozigosidade , Reação em Cadeia da Polimerase , Deleção de SequênciaRESUMO
Our laboratory previously reported a high frequency of loss of heterozygosity (LOH) at 1p32-p33 in endometrial cancers. LOH at 1p32-p33 is a specific feature of one of the most aggressive forms of endometrial carcinoma, uterine papillary serous cancer (UPSC). The minimum region of allelic loss in UPSC is defined by D1S190 and D1S447, an interval corresponding to less than 1 cM. Here we describe the construction and characterization of a sequence-ready clone contig that spans the deletion region. The contig consists of 24 bacterial artificial chromosome clones and 18 P1 artificial chromosome clones and spans approximately 1050 kb. The consensus region of allelic loss between D1S190 and D1S447 represents approximately 792 kb. Eight previously described ESTs have been positioned within the contig.
Assuntos
Deleção Cromossômica , Cromossomos Humanos Par 1 , Neoplasias do Endométrio/genética , Southern Blotting , Mapeamento de Sequências Contíguas , Etiquetas de Sequências Expressas , Feminino , Genes Bacterianos , Marcadores Genéticos , Humanos , Perda de Heterozigosidade , Modelos Genéticos , Mapeamento por RestriçãoRESUMO
Common fragile sites have been proposed to play a mechanistic role in chromosome translocations and other rearrangements in cancer cells in vivo based on their behavior in vitro and their co-localization with cancer translocation breakpoints. This hypothesis has been the subject of controversy, because associations have been made at the chromosomal level and because of the large number of both fragile sites and cancer chromosome breakpoints. Tests of this hypothesis at the molecular level are now possible with the cloning of common fragile site loci and the use of fragile site clones in the analysis of rearranged chromosomes. FRA3B, the most frequently seen common fragile site, lies within the large FHIT gene. It is now well established that this region is the site of frequent, large intragenic deletions and aberrant transcripts in a number of tumors and tumor cell lines. In contrast, only one tumor-associated translocation involving the FHIT gene has been reported. We have found translocations in both homologs of chromosome 3 in an early-passage esophageal adenocarcinoma cell line. This cell line showed no normal FHIT transcripts by reverse transcription polymerase chain reaction. Subsequent chromosome analysis showed translocations of the short arms of both homologs of chromosome 3: t(3;16) and t(3;4). The breakpoints of both translocations were shown by fluorescence in situ hybridization and polymerase chain reaction to be in the FHIT gene, at or near the center of the fragile site region. Using rapid amplification of cDNA ends with FHIT primers, a noncoding chimeric transcript resulting from t(3;16) was identified. These data provide direct support for the hypothesis that FRA3B, and likely other common fragile sites, may be "hot spots" for translocations in certain cancers, as they are for deletions, and that such translocations have the potential to form abnormal chimeric transcripts. In addition, the results suggest selection for loss of a functional FHIT gene by the translocation events.
Assuntos
Hidrolases Anidrido Ácido , Adenocarcinoma/genética , Quebra Cromossômica/genética , Fragilidade Cromossômica/genética , Cromossomos Humanos Par 3/genética , Neoplasias Esofágicas/genética , Proteínas de Neoplasias/genética , Proteínas/genética , Translocação Genética/genética , Sequência de Aminoácidos , Sequência de Bases , Sítios Frágeis do Cromossomo , Cromossomos Humanos Par 16/genética , Cromossomos Humanos Par 4/genética , Humanos , Masculino , Dados de Sequência Molecular , Homologia de Sequência do Ácido Nucleico , Células Tumorais CultivadasRESUMO
The molecular genetic events underlying endometrial tumorigenesis are ill-defined at present. We have identified a region on the short arm of chromosome 1 which is frequently deleted in endometrial cancers. The region of deletion has been localized to bands 1p32-33. Deletion of 1p32-33 is seen more frequently in cancers of the highly aggressive papillary serous type than in cancers of the less-aggressive endometrioid type. These data suggest the presence of a tumor suppressor gene on 1p32-33 which is specifically involved in the development of endometrial cancers with poor outcome.