RESUMO
BACKGROUND: A subgroup of anaplastic lymphoma kinase (ALK)-rearranged lung tumours can respond to ALK inhibitors. Until now, the ALK status in circulating tumour cells (CTCs) isolated from patients with lung cancer has not been characterised. We assessed the ALK status in CTCs detected in patients with lung cancer and correlated the results to the ALK status defined in the corresponding tumour tissue. PATIENTS AND METHODS: A total of 87 patients with lung adenocarcinoma showing CTCs isolated using the isolation by size of epithelial tumour cell method were screened for their ALK status both in tumour samples and in CTCs. ALK break-apart fluorescence in situ hybridisation (FISH) and immunoreactivity analyses using an anti-ALK antibody (5A4 clone) were carried out on CTCs and compared with the results obtained in the corresponding tissue specimens. RESULTS: A total of five patients showed ALK-gene rearrangement and strong ALK protein expression in CTCs and in the corresponding tumour samples. Both ALK-FISH and ALK immunoreactivity analyses show negative results in CTCs and corresponding tumour samples for 82 patients. Conclusions We demonstrated that the ALK status can be determined in CTCs isolated from patients with lung cancer by immunocytochemistry and FISH analyses. These results favour non-invasive, ALK-gene status pre-screening on a routine basis on CTCs isolated from patients with lung cancer and open new avenues for real-time monitoring for adapted targeted therapy.
Assuntos
Adenocarcinoma/genética , Adenocarcinoma/patologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Células Neoplásicas Circulantes/metabolismo , Receptores Proteína Tirosina Quinases/genética , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/enzimologia , Adenocarcinoma de Pulmão , Adulto , Idoso , Idoso de 80 Anos ou mais , Quinase do Linfoma Anaplásico , Crizotinibe , Feminino , Rearranjo Gênico , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/enzimologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Pirazóis/uso terapêutico , Piridinas/uso terapêutico , Receptores Proteína Tirosina Quinases/metabolismo , Translocação GenéticaRESUMO
PURPOSE: Lung cancer and atherosclerosis share common risk factors. Literature data suggest that the prevalence of lung malignancy in patients with peripheral arterial disease (PAD) is higher than in the general population. Our goal was to determine, through a systematic literature review, the prevalence of lung cancer in patients with PAD. METHODS: We consulted available publications in the Cochrane library, MEDLINE, PUBMED, EMBASE, and ClinicalTrials.gov. We included all articles, written in English or French, published between 1990 and 2020 reporting the prevalence of lung cancer in patients with PAD (atherosclerotic aortic aneurysm or peripheral occlusive diseases). Patients with coronary artery disease, cardiac valvulopathy or carotid stenosis were not included. We did not include case reports. We performed a critical analysis of each article. Data were collected from two independent readers. A fixed effect model meta-analysis allowed to estimate a summary prevalence rate. RESULTS: We identified 303 articles, and selected 19 articles according to selection criteria. A total of 16849 patients were included (mean age 68.3 years, 75.1% of males). Aortic aneurysms were found in 29% of patients and atherosclerotic occlusive disease in 66% of patients. Lung cancer was identified in 538 patients, representing a prevalence of 3%. DISCUSSION: Lung cancer is found in 3% of patients with atherosclerotic PAD. This prevalence is higher than that found in lung cancer screening programs performed in the general population of smokers and former smokers. These patients should be screened for lung cancer. Their selection may dramatically increase the benefit of lung cancer screening.
Assuntos
Aneurisma Aórtico/epidemiologia , Neoplasias Pulmonares/epidemiologia , Doença Arterial Periférica/epidemiologia , Idoso , Aneurisma Aórtico/diagnóstico por imagem , Detecção Precoce de Câncer , Feminino , Humanos , Neoplasias Pulmonares/diagnóstico , Masculino , Pessoa de Meia-Idade , Doença Arterial Periférica/diagnóstico , Prevalência , Prognóstico , Medição de Risco , Fatores de Risco , Fatores de TempoRESUMO
Chronic hepatitis B (HBV) infection is a major risk factor for hepatocellular carcinoma (HCC). Most HCCs complicate the evolution of an active or inactive cirrhosis. However, some tumors occur on livers with minimal histological changes; the prevalence of such cases varies from one geographical region to the other, being much higher in the Southern half of Africa (around 40% of HCCs) than in Asia, America and Europe, where at least 90% of HCCs are associated in the cirrhosis. This heterogeneity is probably a reflection of different environmental and genetic factors. This review will summarise the current knowledge on the mechanisms involved in HBV-related liver carcinogenesis. It will show in particular how viruses can be viewed as tools to discover and dissect new cellular pathways involved in cancer development and emphasize the potential synergistic effects between HBV and hepatitis C virus (HCV), as well as between viral infections and other environmental factors, such as alcohol.
Assuntos
Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/virologia , Hepatite B Crônica/complicações , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/virologia , Alcoolismo , Animais , Carcinoma Hepatocelular/epidemiologia , DNA Viral/sangue , Hepacivirus , Antígenos de Superfície da Hepatite B/sangue , Vírus da Hepatite B/genética , Hepatite B Crônica/virologia , Hepatite C/complicações , Humanos , Cirrose Hepática/complicações , Cirrose Hepática/virologia , Neoplasias Hepáticas/epidemiologia , Camundongos , Fatores de Risco , Transativadores/genética , Transativadores/fisiologia , Proteínas Virais Reguladoras e AcessóriasRESUMO
Some chemotherapeutic agents can elicit apoptotic cancer cell death, thereby activating an anticancer immune response that influences therapeutic outcome. We previously reported that anthracyclins are particularly efficient in inducing immunogenic cell death, correlating with the pre-apoptotic exposure of calreticulin (CRT) on the plasma membrane surface of anthracyclin-treated tumor cells. Here, we investigated the role of cellular Ca(2+) homeostasis on CRT exposure. A neuroblastoma cell line (SH-SY5Y) failed to expose CRT in response to anthracyclin treatment. This defect in CRT exposure could be overcome by the overexpression of Reticulon-1C, a manipulation that led to a decrease in the Ca(2+) concentration within the endoplasmic reticulum lumen. The combination of Reticulon-1C expression and anthracyclin treatment yielded more pronounced endoplasmic reticulum Ca(2+) depletion than either of the two manipulations alone. Chelation of intracellular (and endoplasmic reticulum) Ca(2+), targeted expression of the ligand-binding domain of the IP(3) receptor and inhibition of the sarco-endoplasmic reticulum Ca(2+)-ATPase pump reduced endoplasmic reticulum Ca(2+) load and promoted pre-apoptotic CRT exposure on the cell surface, in SH-SY5Y and HeLa cells. These results provide evidence that endoplasmic reticulum Ca(2+) levels control the exposure of CRT.
Assuntos
Antraciclinas/farmacologia , Cálcio/metabolismo , Calreticulina/metabolismo , Membrana Celular/metabolismo , Retículo Endoplasmático/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Apoptose , Brefeldina A/farmacologia , Linhagem Celular Tumoral , Células HeLa , Homeostase , Humanos , Inibidores da Síntese de Proteínas/farmacologiaRESUMO
By pumping calcium from the cytosol to the ER, sarco/endoplasmic reticulum calcium ATPases (SERCAs) play a major role in the control of calcium signaling. We describe two SERCA1 splice variants (S1Ts) characterized by exon 4 and/or exon 11 splicing, encoding COOH terminally truncated proteins, having only one of the seven calcium-binding residues, and thus unable to pump calcium. As shown by semiquantitative RT-PCR, S1T transcripts are differentially expressed in several adult and fetal human tissues, but not in skeletal muscle and heart. S1T proteins expression was detected by Western blot in nontransfected cell lines. In transiently transfected cells, S1T homodimers were revealed by Western blot using mildly denaturing conditions. S1T proteins were shown, by confocal scanning microscopy, to colocalize with endogenous SERCA2b into the ER membrane. Using ER-targeted aequorin (erAEQ), we have found that S1T proteins reduce ER calcium and reverse elevation of ER calcium loading induced by SERCA1 and SERCA2b. Our results also show that SERCA1 variants increase ER calcium leakage and are consistent with the hypothesis of a cation channel formed by S1T homodimers. Finally, when overexpressed in liver-derived cells, S1T proteins significantly induce apoptosis. These data reveal a further mechanism modulating Ca(2+) accumulation into the ER of nonmuscle cells and highlight the relevance of S1T proteins to the control of apoptosis.
Assuntos
Apoptose , ATPases Transportadoras de Cálcio/metabolismo , Cálcio/metabolismo , Retículo Endoplasmático/metabolismo , Splicing de RNA , Adulto , Sequência de Aminoácidos , ATPases Transportadoras de Cálcio/química , ATPases Transportadoras de Cálcio/genética , Clonagem Molecular , Dimerização , Expressão Gênica , Células HeLa , Humanos , Membranas Intracelulares/metabolismo , Dados de Sequência Molecular , Isoformas de Proteínas/química , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Estrutura Secundária de Proteína , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático , Distribuição Tecidual , Células Tumorais CultivadasRESUMO
As discussed in detail in other chapters of this review, chronic hepatitis B (HBV) infection is a major risk factor for hepatocellular carcinoma (HCC). Most HCCs complicate the evolution of an active or inactive cirrhosis. However, some tumors occur on livers with minimal histological changes; the prevalence of such cases varies from one geographical region to the other, being much higher in the southern half of Africa (around 40% of HCCs) than in Asia, America and Europe, where at least 90% of HCCs are associated with the cirrhosis. This heterogeneity is probably a reflection of different environmental and genetic factors. This review will summarize the current knowledge on the mechanisms involved in HBV-related liver carcinogenesis. It will show in particular how viruses can be viewed as tools to discover and dissect new cellular pathways involved in cancer development and emphasize the potential synergistic effects between HBV and hepatitis C virus, as well as between viral infections and other environmental factors, such as alcohol.
Assuntos
Carcinoma Hepatocelular/virologia , Vírus da Hepatite B/patogenicidade , Neoplasias Hepáticas/virologia , Carcinoma Hepatocelular/química , Carcinoma Hepatocelular/metabolismo , Hepacivirus/genética , Hepacivirus/patogenicidade , Vírus da Hepatite B/genética , Humanos , Neoplasias Hepáticas/química , Neoplasias Hepáticas/metabolismoRESUMO
The hepatitis B virus (HBV) X protein (HBx) is a transcriptional transactivator that has been implicated in the development of HBV-related hepatocellular carcinoma. Mutations in the HBx open reading frame have been reported, but their general impact on the biological function of HBx remains unknown. To address this issue, we comparatively analyzed the structures and biological functions of HBx sequences isolated from sera and from tumor and nontumor tissues of patients with a HBV-related hepatocellular carcinoma. In addition to the HBx sequences derived from free HBV genomes, HBx from HBV integrants was also obtained from the tumor tissues by use of a HBx-Alu PCR-based approach. Sequence analysis showed that the HBx sequences derived from tumor tissues (6 of 7), particularly those isolated from HBV integrants (4 of 4), contained a deletion in the distal COOH-terminal region. Interestingly, most of the COOH-terminally truncated HBx sequences obtained from tumor tissues, in contrast to the full-length HBx isolated from the sera and nontumor tissues, lost their transcriptional activity and their inhibitory effects on cell proliferation and transformation. Importantly, although full-length HBx suppressed the focus formation induced by the cooperation of ras and myc oncogenes in primary rat embryo fibroblasts, COOH-terminally truncated HBx enhanced the transforming ability of ras and myc. Finally, by analyzing the artificial mutants, we were able to more precisely map the functional domains located at the COOH-terminal of HBx. Taken together, our results suggest a key role for the HBx COOH-terminal end in controlling cell proliferation, viability, and transformation. This study further supports the hypothesis that natural HBx mutants might be selected in tumor tissues and play a role in hepatocarcinogenesis by modifying the biological functions of HBx.
Assuntos
Carcinoma Hepatocelular/virologia , Vírus da Hepatite B/genética , Neoplasias Hepáticas/virologia , Mutação , Transativadores/fisiologia , Sequência de Aminoácidos , Apoptose/fisiologia , Carcinoma Hepatocelular/química , Carcinoma Hepatocelular/genética , Genes myc/fisiologia , Genes ras/fisiologia , Inibidores do Crescimento/genética , Inibidores do Crescimento/fisiologia , Humanos , Neoplasias Hepáticas/química , Neoplasias Hepáticas/genética , Dados de Sequência Molecular , Estrutura Terciária de Proteína , Homologia de Sequência de Aminoácidos , Transativadores/genética , Transativadores/isolamento & purificação , Ativação Transcricional , Transfecção , Proteínas Virais Reguladoras e AcessóriasRESUMO
OBJECTIVE: We aimed at developing a method to recover trophoblastic cells from the cervix through a completely non-invasive approach and obtaining a genetic proof of their fetal nature implying that they can be used for non-invasive prenatal diagnosis (NIPD). METHODS: We studied obstetrical samples from 21 pregnant women between 8 and 12 weeks of gestation scheduled for chorionic villus sampling or undergoing elective termination of pregnancy. A cytobrush was used to extract cells from the external parts of the cervix and transferred to 10 ml of preservative solution. Cells were layered on filters with 8 microns pores using the ISET system (Isolation by SizE of Tumor/Trophoblastic cells) and stained. Putative fetal cells were collected by single cell laser-assisted microdissection and identified as fetal or maternal cells by Short Tandem Repeat genotyping. NIPD was blindly performed on 6 mothers at risk of having a fetus with Cystic Fibrosis or Spinal Muscular Atrophy. RESULTS: Trophoblastic cells were recovered from all tested cervical samples with a frequency of 2-12 trophoblasts per 2 ml. NIPD was blindly obtained and verified in 6 mothers at risk of having a fetus with Cystic Fibrosis or Spinal Muscular Atrophy. DISCUSSION: Although larger confirmation studies are required, this is the first report providing a solid proof of principle that trophoblasts can be consistently and safely recovered from cervical samples. Since they are a source of pure fetal DNA, i.e. fetal DNA not mixed with maternal DNA, they constitute an ideal target to develop NIPD of recessive diseases, which is a technical challenge for methods based on cell free DNA.
Assuntos
Colo do Útero/citologia , Técnicas de Genotipagem/métodos , Diagnóstico Pré-Natal/métodos , Análise de Célula Única/métodos , Trofoblastos/citologia , Amostra da Vilosidade Coriônica/métodos , Fibrose Cística/diagnóstico , Fibrose Cística/genética , Feminino , Testes Genéticos/métodos , Humanos , Masculino , Atrofia Muscular Espinal/diagnóstico , Atrofia Muscular Espinal/genética , Gravidez , Primeiro Trimestre da GravidezRESUMO
Proviral tagging has been used in animals as a powerful tool for cancer genetics. We show that a similar approach is possible in patients with hepatocellular carcinoma (HCC) infected by Hepatitis B Virus (HBV), a human pararetrovirus which may act by insertional mutagenesis. In this work, the HBV genome is used as a probe to identify cancer-related genes. By using HBV-Alu-PCR, we obtained 21 HBV/cellular DNA junctions from 18 different patients. In six of 21, we found the HBV DNA integrated into a cellular gene: (1) Sarco/Endoplasmic Reticulum Calcium ATPase1 Gene; (2) Thyroid Hormone Receptor Associated Protein 150 alpha Gene; (3) Human Telomerase Reverse Transcriptase Gene; (4) Minichromosome Maintenance Protein (MCM)-Related Gene; (5) FR7, a new gene expressed in human liver and cancer tissues; and (6) Nuclear Matrix Protein p84 Gene. Seven junctions contained unique cellular sequences. In the remaining eight, the HBV DNA was next to repetitive sequences, five of them of LINE1 type. The cellular genes targeted by HBV are key regulators of cell proliferation and viability. Our results show that studies on HBV-related HCCs allow to identify cellular genes involved in cancer. We therefore propose this approach as a valuable tool for functional cancer genomic studies in humans.
Assuntos
Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/virologia , DNA/metabolismo , Vírus da Hepatite B/genética , Reação em Cadeia da Polimerase/métodos , Sequência de Bases , Northern Blotting , Divisão Celular , DNA Complementar/metabolismo , Éxons , Humanos , Íntrons , Modelos Genéticos , Dados de Sequência Molecular , Mutação , Sequências Repetitivas de Ácido NucleicoRESUMO
We have used the Hepatitis B Virus DNA genome as a probe to identify genes clonally mutated in vivo, in human liver cancers. In a tumor, HBV-DNA was found to be integrated into the gene encoding Sarco/Endoplasmic Reticulum Calcium ATPase (SERCA), which pumps calcium, an important intracellular messenger for cell viability and growth, from the cytosol to the endoplasmic reticulum. The HBV X gene promoter cis-activates chimeric HBV X/SERCA1 transcripts, with splicing of SERCA1 exon 11, encoding C-terminally truncated SERCA1 proteins. Two chimeric HBV X/SERCA1 proteins accumulate in the tumor and form dimers. In vitro analyses have demonstrated that these proteins localize to the ER, determine its calcium depletion and induce cell death. We have also shown that these biological effects are related to expression of the SERCA, rather than of the viral moiety. This report involves for the first time the expression of mutated SERCA proteins in vivo in a tumor cell proliferation and in vitro in the control of cell viability. Oncogene (2000).
Assuntos
Apoptose/genética , ATPases Transportadoras de Cálcio/genética , Vírus da Hepatite B/fisiologia , Mutagênese Insercional/genética , Idoso , ATPases Transportadoras de Cálcio/metabolismo , Dimerização , Humanos , RNA Mensageiro/genética , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Retículo Sarcoplasmático/enzimologia , Células Tumorais Cultivadas , Integração ViralRESUMO
We compared the efficacy of 4 methods for isolating circulating tumor cells: immunocapture with Ber-EP4-coated magnetic beads, density gradient separation, ammonium chloride, and distilled water-mediated erythrocyte lysis. Human blood from healthy volunteers was mixed with serial dilutions of prostate (LNCaP) and liver (HepG2) derived tumor cells. Isolation of circulating tumor cells was followed by reverse transcriptase-polymerase chain reaction with primers specific for prostate-specific antigen and alpha-fetoprotein. Ber-EP4 antigen expression was evaluated by immunohistochemistry in 27 hepatocellular carcinomas and 34 prostate adenocarcinomas. Peripheral blood samples from 12 patients with hepatocellular carcinoma and 10 with prostate adenocarcinoma also were tested. Density gradient separation and Ber-EP4 immunocapture were the most sensitive techniques for isolating circulating tumor cells in in vitro tests. Isolation by density gradient separation was significantly more sensitive than Ber-EP4 immunocapture when applied to peripheral blood samples of patients with cancer, a result consistent with the variable expression of Ber-EP4 antigen that we found by immunohistochemistry in prostate adenocarcinomas and hepatocellular carcinomas.
Assuntos
Antígenos de Superfície/imunologia , Biomarcadores Tumorais/imunologia , Separação Imunomagnética/métodos , Células Neoplásicas Circulantes , Adenocarcinoma/sangue , Cloreto de Amônio/farmacologia , Anticorpos Monoclonais , Carcinoma Hepatocelular/sangue , Centrifugação com Gradiente de Concentração/métodos , Primers do DNA/química , DNA de Neoplasias/análise , Células Epiteliais/imunologia , Células Epiteliais/patologia , Estudos de Avaliação como Assunto , Hemólise/efeitos dos fármacos , Humanos , Técnicas Imunoenzimáticas , Neoplasias Hepáticas/sangue , Masculino , Células Neoplásicas Circulantes/imunologia , Células Neoplásicas Circulantes/patologia , Antígeno Prostático Específico/genética , Neoplasias da Próstata/sangue , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sensibilidade e Especificidade , Células Tumorais Cultivadas , alfa-Fetoproteínas/genéticaRESUMO
Interest in biomarkers in the field of thoracic oncology is focused on the search for new robust tests for diagnosis (in particular for screening), prognosis and theragnosis. These biomarkers can be detected in tissues and/or cells, but also in biological fluids, mainly the blood. In this context, there is growing interest in the detection of circulating tumor cells (CTCs) in the blood of lung cancer patients since CTC identification, enumeration and characterization may have a direct impact on diagnosis, prognosis and theragnosis in the daily clinical practice. Many direct and indirect methods have been developed to detect and characterize CTCs in lung cancer patients. However, these different approaches still hold limitations and many of them have demonstrated unequal sensitivity and specificity. Indeed, these methods hold advantages but also certain disadvantages. Therefore, despite the promises, it is currently difficult and premature to apply this methodology to the routine care of lung cancer patients. This situation is the consequence of the analysis of the methodological approaches for the detection and characterization of CTCs and of the results published to date. Finally, the advent of targeted cancer therapies in thoracic oncology has stimulated considerable interest in non-invasive detection of genomic alterations in tumors over time through the analysis of CTCs, an approach that may help clinicians to optimize therapeutic strategies for lung cancer patients. We describe here the main methods for CTC detection, the advantages and limitations of these different approaches and the potential usefulness and value of CTC characterization in the field of thoracic oncology.
Assuntos
Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/terapia , Células Neoplásicas Circulantes/patologia , Humanos , Terapia de Alvo Molecular , Metástase Neoplásica , Células Neoplásicas Circulantes/metabolismo , PrognósticoRESUMO
Cystic fibrosis (CF) is a frequently fatal autosomal recessive inherited disease affecting around one in 3000 newborns in France, the carrier frequency varying from one in 20 to one in 40 subjects depending on the geographical area. The disease is caused by a chloride channel defect that is attributable to mutations in the gene that encodes the CF transmembrane conductance regulator (CFTR). Approximately, 1200 different mutations have been discovered. Among them, the F508del mutation accounts for 70% of mutated alleles worldwide. Prenatal diagnosis (PND) of inherited monogenic disorders such as CF currently relies on invasive procedures--amniocentesis, chorionic villus sampling (CVS)--which carry a significant risk of miscarriage (from 0.5 to 3%). Several methods have been proposed to enrich circulating fetal cells (CFCs) from blood and use them in PND. However, up to now, no assay has been shown to be reliable enough for routine application in place of the invasive protocols. When combined with laser microdissection, isolation by size of epithelial tumor/trophoblastic cells (ISET) allows mutation analysis of DNA from single cells demonstrated to be fetal (circulating fetal trophoblastic cells [CFTC]) by short tandem repeat (STR) genotyping and uncontaminated with maternal DNA. Application of this protocol to 12 couples at risk of having a child affected by CF has shown, in a blind study, that the new method affords a reliable and safe PND of affected fetus, healthy carrier or normal non carrier fetus. A following prospective blind study has then been performed on 32 couples at risk of having an affected child. For each mother, five or 10 CFTCs have been analyzed with an individual genetic diagnosis performed per CFTC. Results have been obtained in 240 CFTC showing that seven mothers were carrying an affected foetus, with 100% sensitivity and 100% specificity. These results open the way to a multicenter clinical validation trial and to the potential future application of the ISET non invasive approach as a reliable alternative to the invasive PND procedures.
Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/genética , Fibrose Cística/diagnóstico , Diagnóstico Pré-Natal/métodos , Fibrose Cística/genética , Análise Mutacional de DNA , Feminino , Humanos , Gravidez , Estudos ProspectivosRESUMO
Despite advanced knowledge on the genetic basis of oxidative phosphorylation-related diseases, the molecular and/or cellular determinants for tissue-specific dysfunction are not completely understood. Here, we report the cellular events associated with mitochondrial respiratory Complex II deficiency occurring before cell death. Mutation or chronic inhibition of Complex II determined a large increase of basal and agonist-evoked Ca(2+) signals in the cytosol and the mitochondria, in parallel with mitochondrial dysfunction characterized by membrane potential (Δψ(mit)) loss, [ATP] reduction and increased reactive oxygen species production. Cytosolic and mitochondrial Ca(2+) overload are linked to increased endoplasmic reticulum (ER) Ca(2+) leakage, and to SERCA2b and PMCA proteasome-dependent degradation. Increased [Ca(2+)](mit) is also contributed by decreased mitochondrial motility and increased ER-mitochondria contact sites. Interestingly, increased intracellular [Ca(2+)] activated on the one hand a compensatory Ca(2+)-dependent glycolytic ATP production and determined on the second hand mitochondrial pathology. These results revealed the primary function for Ca(2+) signalling in the control of mitochondrial dysfunction and cellular bioenergetics outcomes linked to respiratory chain Complex II deficiency.
Assuntos
Sinalização do Cálcio , Cálcio/metabolismo , Complexo II de Transporte de Elétrons/metabolismo , Metabolismo Energético , Mitocôndrias/metabolismo , Trifosfato de Adenosina/metabolismo , Apoptose , Células Cultivadas , Regulação para Baixo , Complexo II de Transporte de Elétrons/deficiência , Complexo II de Transporte de Elétrons/genética , Retículo Endoplasmático/metabolismo , Fibroblastos/metabolismo , Humanos , Potencial da Membrana Mitocondrial/fisiologia , Nitrocompostos/farmacologia , ATPases Transportadoras de Cálcio da Membrana Plasmática/metabolismo , Propionatos/farmacologia , Piridonas/farmacologia , Espécies Reativas de Oxigênio/metabolismo , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismoRESUMO
BACKGROUND AND AIMS: Hepatitis B virus (HBV) DNA integration into or close to cellular genes is frequently detected in HBV positive hepatocellular carcinomas (HCC). We have previously shown that viral integration can lead to aberrant target gene transcription. In this study, we attempted to investigate common pathways to hepatocarcinogenesis. METHODS: By using a modified Alu-polymerase chain reaction approach, we analysed 50 HCCs along with 10 previously published cases. RESULTS: Sixty eight cellular flanking sequences (seven repetitive or unidentified sequences, 42 cellular genes, and 19 sequences potentially coding for unknown proteins) were obtained. Fifteen cancer related genes and 25 cellular genes were identified. HBV integration recurrently targeted the human telomerase reverse transcriptase gene (three cases) and genes belonging to distinct pathways: calcium signalling related genes, 60s ribosomal protein encoding genes, and platelet derived growth factor and mixed lineage leukaemia encoding genes. Two tumour suppressor genes and five genes involved in the control of apoptosis were also found at the integration site. The viral insertion site was distributed over all chromosomes except 13, X, and Y. CONCLUSIONS: In 61/68 (89.7%) cases, HBV DNA was integrated into cellular genes potentially providing cell growth advantage. Identification of recurrent viral integration sites into genes of the same family allows recognition of common cell signalling pathways activated in hepatocarcinogenesis.
Assuntos
Carcinoma Hepatocelular/genética , DNA Viral/genética , Vírus da Hepatite B/genética , Hepatite B/genética , Neoplasias Hepáticas/genética , Integração Viral , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Sinalização do Cálcio/genética , Carcinoma Hepatocelular/virologia , Elementos de DNA Transponíveis/genética , Proteínas de Ligação a DNA , Feminino , Genes Supressores de Tumor , Humanos , Leucemia/genética , Neoplasias Hepáticas/virologia , Masculino , Pessoa de Meia-Idade , Proteínas de Neoplasias/genética , Fator de Crescimento Derivado de Plaquetas/genética , Reação em Cadeia da Polimerase/métodos , Proteínas Ribossômicas/genética , Telomerase/genética , Proteínas Virais/genéticaRESUMO
Hepatocellular carcinoma (HCC) is the most common histological form of primary liver cancer; the tumor cells having retained features of hepatocytic differentiation. It is important to emphasize the heterogeneity of the histological background on which the tumor develops. Most HCCs complicate the evolution of an active or inactive cirrhosis. However, some tumors occur on livers with minimal histological changes; the prevalence of such cases varies from one geographical region to the other; being much higher in the southern half of Africa (around 40% of HCCs) than in Asia, America and Europe, where at least 90% of HCCs are associated in the cirrhosis. This heterogeneity is probably a reflection of different environmental and genetic factors. A large number of epidemiological and molecular studies have indeed clearly demonstrated the prime importance of environmental factors to the development of primary liver cancers in humans. Chronic hepatitis B (HBV) and C (HCV) infections are major risk factors. This review will mainly analyse the impact of chronic HBV infection but it is important to emphasize the potential synergistic effects between HBV and HCV, as well as between viral infections and other environmental factors, such as alcohol, chemical carcinogens (see review by Dr Wogan) and other, still poorly defined, hormonal factors which may account for the higher incidence of the tumor in man. Finally the review by Dr Buendia highlights the emerging issue of liver-cancer genetics.
Assuntos
Carcinoma Hepatocelular/virologia , Hepatite B Crônica/virologia , Neoplasias Hepáticas/virologia , Apoptose , Carcinoma Hepatocelular/patologia , Ciclo Celular , DNA Viral/análise , Genoma Viral , Antígenos de Superfície da Hepatite B/análise , Vírus da Hepatite B/genética , Hepatite B Crônica/genética , Hepatite B Crônica/patologia , Hepatite C Crônica/genética , Hepatite C Crônica/patologia , Hepatite C Crônica/virologia , Humanos , Neoplasias Hepáticas/patologia , Transcrição Gênica/genética , Células Tumorais Cultivadas/efeitos dos fármacos , Integração ViralRESUMO
The circulation of liver-derived cells in patients with hepatocellular carcinoma (HCC) has been demonstrated by reverse transcriptase-polymerase chain reaction (RT-PCR) analyses. Contrasting results have been reported until now about the clinical impact of these assays, mainly due to technical differences. The use of RT-PCR approaches is now clearly, not suitable for recognition of circulating tumorous cells (CTC) when the test is performed after invasive medical or surgical procedures. Furthermore, the RT-PCR approach is incapable of analyzing the expression of invasion-related genes in CTC. Recently, new assays have been proposed to isolate CTC. They allow immunomorphological and molecular characterization of individual tumor cells. Based on these new results, new therapeutic approaches of metastases should be developed in the near future.
Assuntos
Carcinoma Hepatocelular/sangue , Neoplasias Hepáticas/sangue , Células Neoplásicas Circulantes , Albuminas/análise , Albuminas/biossíntese , Marcadores Genéticos , Humanos , Células Neoplásicas Circulantes/patologia , RNA Mensageiro/análise , RNA Mensageiro/sangue , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sensibilidade e Especificidade , Transcrição Gênica , Células Tumorais Cultivadas , alfa-Fetoproteínas/análise , alfa-Fetoproteínas/biossínteseRESUMO
Deletions of the Tg737 gene, whose product is involved in liver oval cell proliferation, differentiation, and ploidy control, have been recently shown in chemically induced rat liver tumors and in a limited series of patients with hepatocellular carcinoma (HCC). Thus, Tg737 has been proposed as a candidate new liver-specific tumor suppressor gene. To investigate this important issue, we analyzed the structure and expression pattern of the Tg737 gene in a group of 23 tumorous and adjacent nontumorous liver tissues, by combining polymerase chain reaction (PCR) and Southern and Northern blot-based analyses. We failed to identify deletions or gross alterations of the Tg737 gene by both PCR and Southern blot analyses. Northern blots showed comparable accumulation of normal Tg737 transcripts in both tumorous and nontumorous tissues. Collectively, therefore, our results do not support the hypothesis of frequent Tg737 genetic alterations in human HCC.
Assuntos
Carcinoma Hepatocelular/genética , Genes Supressores de Tumor , Neoplasias Hepáticas/genética , Proteínas/genética , Proteínas Supressoras de Tumor , Southern Blotting , Éxons , Humanos , Reação em Cadeia da PolimeraseRESUMO
AIM: To assess the effect of laparoscopy on circulating tumor cell (CTC) detection in case of carcinosis. MATERIAL AND METHODS: We compared laparoscopy versus laparotomy on tumor cell blood release in an animal model of ovarian carcinosis obtained by intraperitoneal inoculation of IGR-OV1 cells in nude rats. Animals were randomly assigned to one of the following groups: CO(2) laparoscopy (L), gasless laparoscopy (GL), midline laparotomy (ML), or general anesthesia as control (C). A 0.5 ml blood sample was taken in each case before and after experiment and tested with a novel assay, ISET (isolation by size of epithelial tumor cells), which isolates CTC by filtration on account of their size. Statistics were performed with the Fisher's and the Chi-square tests. RESULTS: Ten rats were included in each group. We did not find any significant difference in CTC prevalence before and after surgery (2/14 versus 3/19, respectively, P = 1). Similarly, the three surgical accesses were equivalent with one post-experiment detection per group: 1/5 for L, 1/7 for ML, 1/7 for GL, and 1/6 for C (P = 0.9). CONCLUSION: This trial did not show any deleterious effect of laparoscopy on CTC when compared to laparotomy.
Assuntos
Laparoscopia/efeitos adversos , Laparotomia/efeitos adversos , Células Neoplásicas Circulantes/patologia , Neoplasias Ovarianas/cirurgia , Animais , Modelos Animais de Doenças , Feminino , Transplante de Neoplasias , Neoplasias Ovarianas/patologia , Distribuição Aleatória , Ratos , Ratos NusRESUMO
Spinal muscular atrophy (SMA) has a prevalence of one in 6000 births and a one in 40 heterozygote frequency. We aimed to develop a routine test for non-invasive prenatal diagnosis. We tested blood with ISET (isolation by size of epithelial tumour or trophoblastic cells) in 12 pregnant women whose babies were at risk of SMA. Using genetic analysis of fetal cells, we identified SMA in all nine isolated from the three mothers carrying an affected child. There was no mutation in any of the 26 fetal cells isolated from the nine women with an unaffected child. Our results show that non-invasive detection of genetic diseases by the analysis of maternal blood is feasible.