Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 40
Filtrar
Mais filtros

País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Surg Endosc ; 35(6): 2817-2822, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-32556763

RESUMO

BACKGROUND: Endoscopic ultrasound (EUS) procedures are becoming more frequent nowadays and novel techniques are on the rise. These procedures require high technical experience and complex endoscopic skills. The goal of this study was to develop a new minimally invasive animal model of bile duct dilatation in the pig, in order to offer a new tool for endoscopic and surgical therapy training and to test new therapeutic strategies. METHODS: Twenty-five female pigs underwent laparoscopic surgery in order to perform a common hepatic duct ligation. A pre- and postoperative biochemical analyses were performed: glucose, albumin, total bilirubin (TBil), gamma glutamyl transferase (GGT), alkaline phosphatase, and alanine aminotransferase were measured. Surgical time and intra- and postoperative complications were registered. Five to six days after surgery, an EUS was performed to measure intrahepatic duct size (mm). Distance from the bile duct to the EUS transductor was also recorded (mm). T-student for quantitative variables was applied. Statistical significance was defined as p value ≤ 0.05. RESULTS: The mean surgical time was 29.5 ± 14.9 min. In five pigs (20%), some mild intraoperative problems occurred. A severe postoperative complication occurred in one animal (4%). No postoperative mortality was registered. Postoperative serum analyses showed an increase in total bilirubin (p = 0.005) and gamma glutamyl transferase levels (p = 0.001). Postoperative EUS showed dilatation of the intrahepatic bile duct in 76% of pigs, with a mean diameter of 9.6 ± 3.6 mm (distance from the gastric wall of 17.0 ± 6.4 mm). CONCLUSION: The surgical procedure described here is a safe technique to induce dilatation of the intrahepatic bile ducts in the pig, with a minimally invasive approach and a high efficacy rate. This animal model might be useful for EUS techniques training and for evaluating new therapeutic approaches.


Assuntos
Procedimentos Cirúrgicos do Sistema Biliar , Laparoscopia , Animais , Ductos Biliares , Ductos Biliares Intra-Hepáticos/cirurgia , Dilatação , Feminino , Suínos
2.
Int J Mol Sci ; 17(4): 484, 2016 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-27043547

RESUMO

KRAS mutations are responsible for resistance to anti-epidermal growth factor receptor (EGFR) therapy in colorectal cancer patients. These mutations sometimes appear once treatment has started. Detection of KRAS mutations in circulating cell-free DNA in plasma ("liquid biopsy") by droplet digital PCR (ddPCR) has emerged as a very sensitive and promising alternative to serial biopsies for disease monitoring. In this study, KRAS G12V mutation was analyzed by ddPCR in plasma DNA from 10 colorectal cancer patients and compared to six healthy donors. The percentage of KRAS G12V mutation relative to wild-type sequences in tumor-derived DNA was also determined. KRAS G12V mutation circulating in plasma was detected in 9 of 10 colorectal cancer patients whose tumors were also mutated. Colorectal cancer patients had 35.62 copies of mutated KRAS/mL plasma, whereas in healthy controls only residual copies were found (0.62 copies/mL, p = 0.0066). Interestingly, patients with metastatic disease showed a significantly higher number of mutant copies than M0 patients (126.25 versus 9.37 copies/mL, p = 0.0286). Wild-type KRAS was also significantly elevated in colorectal cancer patients compared to healthy controls (7718.8 versus 481.25 copies/mL, p = 0.0002). In conclusion, KRAS G12V mutation is detectable in plasma of colorectal cancer patients by ddPCR and could be used as a non-invasive biomarker.


Assuntos
Neoplasias Colorretais/patologia , DNA de Neoplasias/sangue , Proteínas ras/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais/uso terapêutico , Biomarcadores Tumorais/genética , Estudos de Casos e Controles , Linhagem Celular Tumoral , Neoplasias Colorretais/sangue , Neoplasias Colorretais/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Reação em Cadeia da Polimerase
3.
Mol Cancer ; 12: 8, 2013 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-23374730

RESUMO

BACKGROUND: To clarify the implications of cell-free nucleic acids (cfNA) in the plasma in neoplastic disease, it is necessary to determine the kinetics of their release into the circulation. METHODS: To quantify non-tumor and tumor DNA and RNA in the plasma of tumor-bearing rats and to correlate such levels with tumor progression, we injected DHD/K12-PROb colon cancer cells subcutaneously into syngenic BD-IX rats. Rats were sacrificed and their plasma was analyzed from the first to the eleventh week after inoculation. RESULTS: The release of large amounts of non-tumor DNA into plasma was related to tumor development from its early stages. Tumor-specific DNA was detected in 33% of tumor-bearing rats, starting from the first week after inoculation and at an increasing frequency thereafter. Animals that were positive for tumor DNA in the plasma had larger tumors than those that were negative (p = 0.0006). However, the appearance of both mutated and non-mutated DNA fluctuated with time and levels of both were scattered among individuals in each group. The release of non-tumor mRNA was unaffected by tumor progression and we did not detect mutated RNA sequences in any animals. CONCLUSIONS: The release of normal and tumor cfDNA into plasma appeared to be related to individual-specific factors. The contribution of tumor DNA to the elevated levels of plasma DNA was intermittent. The release of RNA into plasma during cancer progression appeared to be an even more selective and elusive phenomenon than that of DNA.


Assuntos
DNA/sangue , RNA/sangue , Animais , Linhagem Celular Tumoral , DNA/genética , Progressão da Doença , Feminino , Masculino , Transplante de Neoplasias , Neoplasias Experimentais/sangue , Proteínas Proto-Oncogênicas p21(ras)/genética , RNA/genética , Ratos
4.
Transl Oncol ; 14(2): 100999, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33348249

RESUMO

INTRODUCTION: The current challenge on renal cell carcinoma (RCC) is to finding a non-invasive biomarker for improving their diagnostic and therapeutic management. In the present study, we analyzed the clinical value of plasma levels of cell-free DNA (cfDNA) and RNA (cfRNA) of two genes: glyceraldehyde 3-phosphate-dehydrogenase (GAPDH) and human telomerase reverse transcriptase (hTERT). MATERIALS AND METHODS: We recruited 82 patients with RCC, and 20 healthy subjects. Using RT-PCR techniques, plasma levels of cfDNA and cfRNA from hTERT and GAPDH genes were quantified pre- and post-operatively, and one year after surgery. Relationships between such plasma levels and clinicopathological features and evolution of disease were analyzed. RESULTS: Levels of GAPDH cfDNA and cfRNA were significantly higher in patients than in healthy subjects. hTERT cfDNA was detected in plasma from 35% of RCC patients and in none healthy subject. At diagnosis, plasma levels of GAPDH cfDNA were higher in advanced pT and TNM stages, and hTERT cfDNA in patients with 3-4 Fuhrman grade and affected lymph nodes. Levels of cfNAs were not related to the presence of metastasis. Following nephrectomy, GAPDH cfDNA levels dropped, and patients with higher levels before and after nephrectomy, showed lower overall survival (OS). However, Cox's multivariate model did not prove any association of the cfNA levels with progression. CONCLUSION: Plasma levels of cfDNA from GADPH and hTERT genes were correlated to tumor diagnosis and progression and, thus, such analyses might help to diagnosis and prognosis of RCC patients.

5.
Eur J Trauma Emerg Surg ; 47(2): 597-606, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31641785

RESUMO

PURPOSE: The abdomen is the second most common source of sepsis and secondary peritonitis, which likely lead to death. In the present study, we hypothesized that instillation of local anesthetics into the peritoneum might mitigate the systemic inflammatory response syndrome (SIRS) in the open abdomen when combined with negative-pressure therapy (NPT) to treat severe peritonitis. METHODS: We performed a study in 21 pigs applying a model of sepsis based on ischemia/reperfusion and fecal spread into the peritoneum. The pigs were randomized into three groups, and treated for 6 h as follows: Group A: temporary abdominal closure with ABTHERA™ Open Abdomen Negative-Pressure Therapy; Group B: temporary abdominal closure with ABTHERA™ Open Abdomen Negative-Pressure Therapy plus abdominal instillation with physiological saline solution (PSS); and Group C: temporary abdominal closure with ABTHERA™ Open Abdomen Negative-Pressure Therapy plus peritoneal instillation with a solution of ropivacaine in PPS. RESULTS: A comparison between the three groups revealed no statistically significant difference for any of the parameters registered (p > 0.05), i.e., intra-abdominal pressure, blood pressure, heart rate, O2 saturation, diuresis, body temperature, and blood levels of interleukin 6 (IL-6), tumor necrosis factor alpha (TNFα), and c-reactive protein (CRP). In addition, histological studies of the liver, ileum, kidney and lung showed no difference between groups. CONCLUSIONS: The use of abdominal instillation (with or without ropivacaine) did not change the effect of 6 h of NPT after sepsis in animals with open abdomen. The absence of adverse effects suggests that longer treatments should be tested.


Assuntos
Tratamento de Ferimentos com Pressão Negativa , Peritonite , Sepse , Animais , Abdome , Peritonite/terapia , Ropivacaina , Suínos
6.
Transl Oncol ; 13(11): 100837, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32736333

RESUMO

Differential presence of exons (DPE) is a method of interpretation of exome sequencing, which has been proposed to design a predictive algorithm with clinical value in patients with colorectal cancer (CRC). The goal of the present study was to examine the reproducibility in a rat model of metastatic colon cancer. DHD/K12-TRb cells were injected in syngenic immunocompetent BD-IX rats. Cells were from two stocks with low and normal metastatic potential, and injected into two separate groups of rats. Five to ten weeks after injection, blood samples were taken prior euthanasia and whole exome sequencing performed. Through DPE analysis, we identified a set of exons whose differential presence in plasma allowed us to compare both groups of tumor-bearing animals. A verification test was performed to confirm that the algorithm was able to classify extracted samples into their corresponding groups of origin. The highest mean probability was 0.8954. In conclusion, the DPE analysis in tumor-bearing animals was able to discriminate between different disease status, which fully supports previous results in CRC patients.

7.
Intensive Care Med Exp ; 8(1): 66, 2020 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-33206250

RESUMO

BACKGROUND: Traumatic brain injury (TBI) is one of the most frequent and severe neurological diseases. In the last few decades, significant advances have been made in TBI pathophysiology and monitoring, however new treatments have not emerged. Although the central nervous system (CNS) has been historically defined as an immunologically privileged organ, recent studies show the increasingly predominant role of inflammatory and apoptotic phenomena in the pathogenesis of TBI. Inflammatory response mediators can be eliminated with continuous renal replacement therapies (CRRT). Our aim was to investigate whether hemofiltration protects the brain after head trauma in an experimental study in animals. METHODS AND RESULTS: A model of TBI and CVVH was performed in anesthetized New Zealand white rabbits without acute renal failure. The experimental group TBI ( +)-CVVH ( +) was compared with a TBI ( +)-CVVH (-) and a TBI (-)-CVVH ( +) control groups. Rabbits were assessed immediately (NES1) and 24 h hours after (NES2) TBI and/or CVVH using a functional Neurological Evaluation Score (NES) and histology of the brains after sacrifice. There was evidence to support a difference of NES1 comparing with the TBI (-)-CVVH ( +), but not with TBI ( +)-CVVH (-) with only 15% of the rabbits treated with CVVH and TBI showing a favorable neurological course. The final neurological outcome (mortality at 24 h) was 0%, 22% and 53% in the TBI(-) + CVVH( +), TBI( +)-CVVH(-) and TBI( +)-CVVH( +) groups respectively. The use of hemofiltration before or after TBI did not make a difference in regards the outcome of the rabbits. There was evidence in the histology to support an increase of mild ischemia, hemorrhage and edema in the experimental group compared with the other two groups. CONCLUSIONS: CVVH in rabbits without renal failure used with the intention to protect the brain may worsen the prognosis in TBI.

8.
Lab Anim (NY) ; 38(6): 211-6, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19455167

RESUMO

The authors evaluated the efficiency and safety of a technique for drawing blood from the cranial vena cava of the hamster (Mesocricetus auratus). They collected blood from Golden Syrian hamsters (n = 15) and from epileptic hamsters (GASH/Sal strain; n = 10) that were anesthetized with isoflurane. Four epileptic hamsters constituted a control group that underwent anesthesia but not blood collection. For blood sampling, a needle connected to a syringe was inserted at a site between 0.2 and 0.6 cm from the manubrium; the depth of insertion was 0.3-1.0 cm. Blood collection was successful in all hamsters except one, and the volume of collected blood ranged from 0.2 ml to 1.5 ml. All hamsters recovered quickly from the procedure, and none showed obvious signs of pain or stress. At necropsy (24 h after the procedure), six subjects showed small local hematomas, and eight showed vascular lacerations of limited severity. Lungs and hearts did not show any damage related to vein puncture. This relatively simple blood collection technique seems to be efficient and safe in hamsters.


Assuntos
Flebotomia/veterinária , Veia Cava Superior , Anestesia/veterinária , Anestésicos Inalatórios , Animais , Cricetinae , Feminino , Isoflurano , Masculino , Mesocricetus , Dor/etiologia , Flebotomia/efeitos adversos
9.
Urol Oncol ; 37(10): 749-757, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-30975552

RESUMO

INTRODUCTION: Elevated mRNA expression of human telomerase reverse transcriptase (hTERT mRNA) is common in many types of tumors, participating in tumor growth and progression. Such expression has not been sufficiently examined in renal cancer. The goal of the present study was to quantify it and analyze its possible clinical value in the management of this pathology. PATIENTS AND METHODS: The study included 111 patients who underwent surgery for renal cell carcinoma (RCC) between 2015 and 2017. Tumor samples were taken from all patients and, in 94 of them, healthy renal tissue adjacent to the tumor was also sampled. The 2 types of tissue were histologically confirmed, after which mRNA was extracted. Using real-time quantitative PCR, the expression of hTERT and glyceraldehyde-3-phosphate dehydrogenase (as endogenous control) were indirectly quantified using the crossing point (CP), which is inversely correlated with the number of sample replicates yielding positive results. These values were correlated with patient socio-demographic variables and clinical-pathological factors of the RCC. RESULTS: The majority of patients were males, with an average age of 60.5 years (SD: 14.02). Most tumors (69.4%) were clear cell carcinomas. The most frequent stages were pT2 or lower (73%), while 5% were pN1 and 12% pM1. The majority of tumors (58%) were Fuhrman grades 1 or 2 (low grade). All samples of tumor and nontumor tissue expressed glyceraldehyde-3-phosphate dehydrogenase mRNA, with the CP in the tumor sample significantly lower than in the nontumor tissue (P < 0.001). The expression of hTERT mRNA was detected in 68% of tumor tissues and significantly correlated with histopathology: 100% in sarcomatoid RCC and 77.9% in clear cell carcinomas (P < 0.0001). The CP was lower in pN1 (P = 0.018), pM1 (P = 0.046), and TNM IV stages (P = 0,041). A greater number of hTERT mRNA replicas were detected in M1 patients (P = 0.0005) and TNM IV stage (P = 0.017). There was no correlation of hTERT mRNA expression with Fuhrman grade. CONCLUSIONS: The quantitation of hTERT mRNA expression in RCC might be useful as a complementary diagnostic tool as well as for assessing aggressiveness of the tumor.


Assuntos
Neoplasias Renais/enzimologia , Neoplasias Renais/genética , RNA Mensageiro/biossíntese , Telomerase/genética , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Feminino , Humanos , Neoplasias Renais/diagnóstico , Masculino , Pessoa de Meia-Idade , Prognóstico , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Telomerase/biossíntese , Telomerase/metabolismo
10.
Cancer Cell ; 35(3): 385-400.e9, 2019 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-30827887

RESUMO

Increasingly effective therapies targeting the androgen receptor have paradoxically promoted the incidence of neuroendocrine prostate cancer (NEPC), the most lethal subtype of castration-resistant prostate cancer (PCa), for which there is no effective therapy. Here we report that protein kinase C (PKC)λ/ι is downregulated in de novo and during therapy-induced NEPC, which results in the upregulation of serine biosynthesis through an mTORC1/ATF4-driven pathway. This metabolic reprogramming supports cell proliferation and increases intracellular S-adenosyl methionine (SAM) levels to feed epigenetic changes that favor the development of NEPC characteristics. Altogether, we have uncovered a metabolic vulnerability triggered by PKCλ/ι deficiency in NEPC, which offers potentially actionable targets to prevent therapy resistance in PCa.


Assuntos
Carcinoma Neuroendócrino/patologia , Regulação para Baixo , Isoenzimas/deficiência , Neoplasias da Próstata/patologia , Proteína Quinase C/deficiência , Serina/metabolismo , Fator 4 Ativador da Transcrição/metabolismo , Vias Biossintéticas , Carcinoma Neuroendócrino/genética , Carcinoma Neuroendócrino/metabolismo , Linhagem Celular Tumoral , Metilação de DNA , Epigênese Genética , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , S-Adenosilmetionina/metabolismo
11.
J Cutan Pathol ; 35(6): 559-65, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18201234

RESUMO

Sarcomatoid carcinomas are rare tumors predominantly composed of spindle cells. This report describes two cases of penile sarcomatoid carcinoma with similar clinicopathological findings. Distinctive features of these tumors were the focal immunostaining that showed the sarcoma-like cells with keratin, smooth muscle actin and p16, and the absence of immunostaining of these cells with p53, S100 protein and desmin. Polymerase chain reaction (PCR) using the GP5+/GP6+ set of primers was positive in both cases. The sequences of the amplified products showed that the implicated genotypes were Human papillomavirus (HPV) 16 and HPV18. To the best of our knowledge, there has been no report in the English literature of HPV-associated penile sarcomatoid carcinoma. These cases might represent an unusual presentation of dedifferentiated carcinoma in which HPV could be shown by a sensitive technique of PCR.


Assuntos
Alphapapillomavirus/isolamento & purificação , Carcinossarcoma/virologia , Infecções por Papillomavirus/complicações , Neoplasias Penianas/virologia , Idoso , Idoso de 80 Anos ou mais , Alphapapillomavirus/genética , Alphapapillomavirus/patogenicidade , Carcinossarcoma/secundário , Carcinossarcoma/cirurgia , DNA de Neoplasias/análise , DNA Viral/análise , Evolução Fatal , Técnica Direta de Fluorescência para Anticorpo , Papillomavirus Humano 16/genética , Papillomavirus Humano 16/isolamento & purificação , Papillomavirus Humano 18/genética , Papillomavirus Humano 18/isolamento & purificação , Humanos , Hibridização In Situ , Masculino , Infecções por Papillomavirus/patologia , Neoplasias Penianas/patologia , Neoplasias Penianas/cirurgia , Análise de Sequência de DNA
12.
Cancer Med ; 7(5): 1706-1716, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29573240

RESUMO

Next-generation sequencing (NGS) has been proposed as a suitable tool for liquid biopsy in colorectal cancer (CRC), although most studies to date have focused almost exclusively on sequencing of panels of potential clinically actionable genes. We evaluated the clinical value of whole-exome sequencing (WES) of cell-free DNA (cfDNA) circulating in plasma, with the goal of identifying differential clinical profiles in patients with CRC. To this end, we applied an original concept, "differential presence of exons" (DPE). We determined differences in levels of 379 exons in plasma cfDNA and used DPE analysis to cluster and classify patients with disseminated and localized disease. The resultant bioinformatics analysis pipeline allowed us to design a predictive DPE algorithm in a small subset of patients that could not be initially classified based on the selection criteria. This DPE suggests that these nucleic acids could be actively released by both tumor and nontumor cells as a means of intercellular communication and might thus play a role in the process of malignant transformation. DPE is a new technique for the study of plasma cfDNA by WES that might have predictive and prognostic value in patients with CRC.


Assuntos
Ácidos Nucleicos Livres/sangue , Neoplasias Colorretais/patologia , Sequenciamento do Exoma/métodos , Metástase Neoplásica/patologia , Ácidos Nucleicos Livres/genética , Neoplasias Colorretais/genética , DNA de Neoplasias/sangue , DNA de Neoplasias/genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Biópsia Líquida , Metástase Neoplásica/genética , Sensibilidade e Especificidade , Análise de Sequência de DNA
13.
Cell Rep ; 23(4): 1178-1191, 2018 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-29694894

RESUMO

Most colorectal cancer (CRC)-related deaths are due to liver metastases. PKCζ is a tumor suppressor in CRC with reduced expression in metastasis. Given the importance of microRNAs (miRNAs) in regulating cellular plasticity, we performed an unbiased screening and identified the miR-200 family as the most relevant miRNAs downregulated by PKCζ deficiency. The regulation of the intracellular levels of miR-200 by PKCζ is post-transcriptional and involves their secretion in extracellular vesicles. Here, we identified ADAR2 as a direct substrate of PKCζ in CRC cells. Phosphorylation of ADAR2 regulates its editing activity, which is required to maintain miR-200 steady-state levels, suggesting that the PKCζ/ADAR2 axis regulates miR-200 secretion through RNA editing. Loss of this axis results in epithelial-to-mesenchymal transition (EMT) and increased liver metastases, which can be inhibited in vivo by blocking miR-200 release. Therefore, the PKCζ/ADAR2 axis is a critical regulator of CRC metastases through modulation of miR-200 levels.


Assuntos
Adenosina Desaminase , MicroRNA Circulante , Neoplasias Colorretais , Neoplasias Hepáticas , MicroRNAs , Proteínas de Neoplasias , Proteína Quinase C , RNA Neoplásico , Proteínas de Ligação a RNA , Adenosina Desaminase/genética , Adenosina Desaminase/metabolismo , Animais , Micropartículas Derivadas de Células/genética , Micropartículas Derivadas de Células/metabolismo , Micropartículas Derivadas de Células/patologia , MicroRNA Circulante/genética , MicroRNA Circulante/metabolismo , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/secundário , Camundongos , Camundongos Knockout , MicroRNAs/genética , Metástase Neoplásica , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Proteína Quinase C/genética , Proteína Quinase C/metabolismo , RNA Neoplásico/genética , RNA Neoplásico/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo
14.
Lab Anim ; 56(2): 204-205, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35511488
15.
World J Clin Oncol ; 8(5): 378-388, 2017 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-29067274

RESUMO

Metastasis is the major cause of mortality in cancer disease and still constitutes one of the most controversial mechanism, not yet fully understood. What is almost beyond doubt is that circulatory system is crucial for cancer propagation. Regarding this system, much attention has been recently paid to liquid biopsy. This technique is aimed to detect circulating tumor cells (CTCs) and circulating nucleic acids so it can be used as a tool for diagnostic, prognostic and follow-up of patients. Whereas CTCs tend to be scarce in serum and plasma from cancer patient, abundant circulating nucleic acids can be detected in the same location. This fact, together with the genetic origin of cancer, stands out the relevance of circulating nucleic acids and shed light into the role of nucleic acids as drivers of metastasis, a recently discovered phenomenon called Genometastasis. This innovative theory supports the transfer of oncogenes from cancer cells to normal and susceptible cells located in distant target organs through circulatory system. What is more, many biological processes haven been described to deliver and secrete circulating nucleic acids into the circulation which can allow such horizontal transfer of oncogenes. In this review, we focus not only on these mechanisms but also we demonstrate its putative role in cancer propagation and give insights about possible therapeutic strategies based on this theory. Our objective is to demonstrate how findings about cell-to-cell communications and previous results can agree with this unprecedented theory.

16.
Head Neck ; 39(4): 647-655, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28225552

RESUMO

BACKGROUND: The use of plasma as a "liquid biopsy" has gained increasing attention. The purpose of the present study was to evaluate the diagnostic and prognostic utility of the perioperative detection and quantitation of mRNAs encoding human telomerase reverse transcriptase (hTERT) and glyceraldehyde 3-phosphate dehydrogenase (GAPDH) in plasma from patients with cancer of the larynx or hypopharynx. METHODS: We recruited 47 patients with laryngeal cancer and 2 patients with hypopharyngeal cancer, plus 27 healthy subjects. A blood sample was taken from each patient before and after surgical resection of the tumor. We quantified hTERT mRNA and GAPDH mRNA in plasma by real-time polymerase chain reaction (PCR). RESULTS: Detection of hTERT mRNA before surgery had diagnostic value (sensitivity, 22%; specificity, 100%). Detection was more frequent in patients with supraglottic tumors than glottic tumors (p = .02) and was related to subsequent recurrence (p = .02). Preoperative levels of hTERT mRNA in plasma were higher in patients with subsequent recurrence (p = .046) and/or metastases (p = .047). The disease-free survival (DFS) and overall survival (OS) of patients with plasma samples positive for hTERT mRNA was poorer than that of patients with negative samples. Mean levels of plasma GAPDH mRNA in untreated patients were higher than in healthy subjects (p < .001). CONCLUSION: Detection and quantitation of hTERT and GAPDH mRNA in patients' plasma might be clinically significant in cases of laryngeal and hypopharyngeal cancer. © 2017 Wiley Periodicals, Inc. Head Neck 39: 647-655, 2017.


Assuntos
Biomarcadores Tumorais/sangue , Carcinoma de Células Escamosas/sangue , Neoplasias Hipofaríngeas/sangue , Neoplasias Laríngeas/sangue , RNA Mensageiro/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/cirurgia , Estudos de Casos e Controles , Intervalo Livre de Doença , Feminino , Humanos , Neoplasias Hipofaríngeas/mortalidade , Neoplasias Hipofaríngeas/patologia , Neoplasias Hipofaríngeas/cirurgia , Estimativa de Kaplan-Meier , Neoplasias Laríngeas/mortalidade , Neoplasias Laríngeas/cirurgia , Laringectomia/métodos , Masculino , Pessoa de Meia-Idade , Assistência Perioperatória/métodos , Reação em Cadeia da Polimerase/métodos , Prognóstico , Estudos Retrospectivos , Espanha , Estatísticas não Paramétricas , Análise de Sobrevida , Resultado do Tratamento
17.
Cancer Lett ; 399: 74-81, 2017 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-28416454

RESUMO

The E1a gene from adenovirus has become a major tool in cancer research. Since the discovery of E1a, it has been proposed to be an oncogene, becoming a key element in the model of cooperation between oncogenes. However, E1a's in vivo behaviour is consistent with a tumour suppressor gene, due to the block/delay observed in different xenograft models. To clarify this interesting controversy, we have evaluated the effect of the E1a 13s isoform from adenovirus 5 in vivo. Initially, a conventional xenograft approach was performed using previously unreported HCT116 and B16-F10 cells, showing a clear anti-tumour effect regardless of the mouse's immunological background (immunosuppressed/immunocompetent). Next, we engineered a transgenic mouse model in which inducible E1a 13s expression was under the control of cytokeratin 5 to avoid side effects during embryonic development. Our results show that E1a is able to block chemical skin carcinogenesis, showing an anti-tumour effect. The present report demonstrates the in vivo anti-tumour effect of E1a, showing that the in vitro oncogenic role of E1a cannot be extrapolated in vivo, supporting its future use in gene therapy approaches.


Assuntos
Proteínas E1A de Adenovirus/metabolismo , Neoplasias Cutâneas/prevenção & controle , Proteínas Supressoras de Tumor/metabolismo , 9,10-Dimetil-1,2-benzantraceno , Proteínas E1A de Adenovirus/genética , Animais , Proliferação de Células , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Feminino , Células HCT116 , Humanos , Melanoma Experimental/genética , Melanoma Experimental/metabolismo , Melanoma Experimental/patologia , Melanoma Experimental/prevenção & controle , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Nus , Camundongos Transgênicos , Transdução de Sinais , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia , Acetato de Tetradecanoilforbol , Fatores de Tempo , Transfecção , Carga Tumoral , Proteínas Supressoras de Tumor/genética
18.
Ann N Y Acad Sci ; 1075: 165-73, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17108207

RESUMO

The "genometastasis hypothesis" proposes that cell-free tumor nucleic acids might be able to transform host stem cells, and that this might be a pathway for the development of metastases. This theory is supported by previous experimental findings and is consistent with observations of other authors. It has been suggested that tumor DNA might be horizontally transferred by the uptake of apoptotic bodies and initiate the genetic changes that are necessary for tumor formation. In addition, apoptotic bodies have been proposed as possible vehicles that protect the nucleic acids circulating in the plasma from enzymatic degradation. In the present study, we analyzed the presence of apoptotic bodies in serum and its relationship with tumor progression in a heterotopic model of colon cancer in the rat. We injected DHD/K12-PROb cancer cells subcutaneously into BD-IX rats and divided the animals into three groups according to the time between the injection of tumor cells and euthanasia. A control group of healthy animals was included (n = 6). After euthanasia, macroscopic metastases were assessed and samples of blood were collected. To detect apoptotic bodies in the sera, each sample was mixed with FITC-conjugated annexin V antibody in combination with propidium iodide and then analyzed by flow cytometry. Detection of apoptotic bodies was only significantly increased in the sera of a few tumor-bearing animals in late stages of tumor development. Thus, such particles appear not to be the vehicle of the cell-free tumor nucleic acids that are detected at early stages of cancer.


Assuntos
Apoptose/fisiologia , Neoplasias do Colo , Ácidos Nucleicos/sangue , Animais , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Modelos Animais de Doenças , Progressão da Doença , Feminino , Humanos , Masculino , Metástase Neoplásica , Distribuição Aleatória , Ratos
19.
Med Clin (Barc) ; 126(12): 452-4, 2006 Apr 01.
Artigo em Espanhol | MEDLINE | ID: mdl-16620731

RESUMO

BACKGROUND AND OBJECTIVE: Epigenetic inactivation is a gene function abnormality that produces no changes in the DNA sequence, with the most frequent epigenetic alteration being hypermethylation of CpG islands in the promoter regions of the genes. Based on recent indications of a potential relationship between mismatch repair genes and renal cell carcinoma (RCC), we were interested in investigating the existence of promoter hypermethylation of the hMLH1 gene in tumor DNA samples from patients with sporadic RCC. MATERIAL AND METHOD: Sixty-five tumor tissue specimens were collected consecutively. The DNA was first obtained and purified, then digested with the restriction enzymes Hpa II and Msp I, followed by polimerase chain reaction amplification of 3 promoter regions of the hMLH1 gene, agarose gel electrophoresis, and densitometric analysis of the images of the amplified bands. RESULTS: Mean patient age was 63.7 years. The most frequent cell type was clear cell carcinoma (67.7%). 73.9% of tumors were diagnosed in stages below pT2, 9.3% had gland involvement and 20%, distant metastasis. No somatic hypermethylation was detected in the promoter region of the hMLH1 gene in any of the patients studied. CONCLUSIONS: Our data indicate that promoter hypermethylation of the hMLH1 gene is not implicated in the pathogenesis of sporadic RCC, and therefore the existence of another type of mutation, microsatellite instability and/or loss of heterozygosity should be examined to determine the possible role of this gene in sporadic RCC.


Assuntos
Carcinoma de Células Renais/genética , Proteínas de Transporte/genética , Neoplasias Renais/genética , Proteínas Nucleares/genética , Proteínas Adaptadoras de Transdução de Sinal , Pareamento Incorreto de Bases , Metilação de DNA , Reparo do DNA , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proteína 1 Homóloga a MutL , Regiões Promotoras Genéticas
20.
Cancer Epidemiol Biomarkers Prev ; 25(2): 399-406, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26604269

RESUMO

BACKGROUND: The ability to undertake molecular analysis to inform on prognosis and predictors of response to therapy is limited by accessibility of tissue. Measurement of total circulating free DNA (cfDNA) or circulating tumor DNA (ctDNA) in peripheral blood may allow easier access to tumor material and help to predict clinical outcomes. METHODS: A systematic review of electronic databases identified publications exploring the association between cfDNA or ctDNA and overall survival (OS) in solid tumors. HRs for OS were extracted from multivariable analyses and included in a meta-analysis. Pooled HRs were computed and weighted using generic inverse variance and random-effect modeling. For studies not reporting multivariable analyses, univariable ORs were estimated from Kaplan-Meier curves for OS at 1 and 3 years. RESULTS: Thirty-nine studies comprising 4,052 patients were included in the analysis. Detection of ctDNA was associated with a significantly worse OS in multivariable analyses [HR, 2.70; 95% confidence interval (CI), 2.02-3.61; P < 0.001). Similar results were observed in the univariable analyses at 3 and 1 year (OR, 4.83; 95% CI, 3.20-7.28; P < 0.001).There was also a statistically significant association between high total cfDNA and worse OS for studies reporting multivariable and univariate data at 3 years (HR, 1.91; 95% CI, 1.59-2.29; P < 0.001 and OR, 2.82; 95% CI, 1.93-4.13; P < 0.001, respectively). CONCLUSIONS: High levels of total cfDNA and presence of ctDNA are associated with worse survival in solid tumors. IMPACT: Circulating DNA is associated with worse outcome in solid tumors.


Assuntos
DNA/genética , Humanos , Neoplasias/mortalidade , Prognóstico
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA