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1.
Ann Hepatobiliary Pancreat Surg ; 24(4): 396-414, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-33234742

RESUMO

BACKGROUNDS/AIMS: The role of immunonutrition (IMN) after liver resections or hepatectomies remains unclear and controversial. We undertook a systematic review to evaluate the effects of IMN on clinical outcomes of patients undergoing hepatectomy. METHODS: Main electronic databases were searched for randomised trials reported clinical outcomes or effects of IMN. The systematic review was conducted in accordance with the PRISMA guideline and meta-analysis was analysed using fixed or random-effects models. RESULTS: Eleven RCTs were identified. A total of 1084 patients (529 IMN and 555 Control) were included in the final pooled analysis. Of these patients, 43% (440/1016) underwent major hepatectomies and the majority are for hepatocellular carcinoma (90%, 956/1055) with Child-Pugh A disease (89%, 793/894). IMN significantly reduced post-operative wound infection (risk ratio (RR) 0.65, 95% confidence interval (CI) 0.43 to 0.96; p=0.03). IMN also had a shorter hospital stay (MD -4.97 days, 95% CI -8.23 to -1.72; p=0.003). There was no statistically significant in other post-operative morbidities and mortality. CONCLUSIONS: Wound infection rate was not significantly different between oral and parenteral IMN group. The length of hospital stay was significantly lower in parenteral IMN group than in oral IMN group. The mortality rates were not affected. Immunonutrition should be recommended routinely as part of the nutritional support in the Enhanced Recovery after Surgery (ERAS) protocol for hepatectomy.

2.
BMC Dev Biol ; 20(1): 4, 2020 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-32098630

RESUMO

BACKGROUND: Pancreatic organoid systems have recently been described for the in vitro culture of pancreatic ductal cells from mouse and human. Mouse pancreatic organoids exhibit unlimited expansion potential, while previously reported human pancreas organoid (hPO) cultures do not expand efficiently long-term in a chemically defined, serum-free medium. We sought to generate a 3D culture system for long-term expansion of human pancreas ductal cells as hPOs to serve as the basis for studies of human pancreas ductal epithelium, exocrine pancreatic diseases and the development of a genomically stable replacement cell therapy for diabetes mellitus. RESULTS: Our chemically defined, serum-free, human pancreas organoid culture medium supports the generation and expansion of hPOs with high efficiency from both fresh and cryopreserved primary tissue. hPOs can be expanded from a single cell, enabling their genetic manipulation and generation of clonal cultures. hPOs expanded for months in vitro maintain their ductal morphology, biomarker expression and chromosomal integrity. Xenografts of hPOs survive long-term in vivo when transplanted into the pancreas of immunodeficient mice. Notably, mouse orthotopic transplants show no signs of tumorigenicity. Crucially, our medium also supports the establishment and expansion of hPOs in a chemically defined, modifiable and scalable, biomimetic hydrogel. CONCLUSIONS: hPOs can be expanded long-term, from both fresh and cryopreserved human pancreas tissue in a chemically defined, serum-free medium with no detectable tumorigenicity. hPOs can be clonally expanded, genetically manipulated and are amenable to culture in a chemically defined hydrogel. hPOs therefore represent an abundant source of pancreas ductal cells that retain the characteristics of the tissue-of-origin, which opens up avenues for modelling diseases of the ductal epithelium and increasing understanding of human pancreas exocrine biology as well as for potentially producing insulin-secreting cells for the treatment of diabetes.


Assuntos
Organoides/citologia , Pâncreas/citologia , Diferenciação Celular/fisiologia , Células Cultivadas , Feminino , Citometria de Fluxo , Instabilidade Genômica/fisiologia , Humanos , Técnicas In Vitro , Lentivirus/genética , Masculino , Técnicas de Cultura de Órgãos , Organoides/metabolismo , Pâncreas/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
3.
J Hum Genet ; 65(2): 199-205, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31619740

RESUMO

Partner and localiser of BRCA2 forms part of a macromolecular complex with BRCA1 and BRCA2, which is critical for the repair of double-strand DNA breaks by homologous DNA recombination. Germline loss-of-function variants in the PALB2 gene may confer an increased lifetime risk of breast, pancreatic, ovarian and other cancers. However, the complete spectrum of predicted pathogenic PALB2 variants associated with each tissue type of cancer remains unknown. A systematic review is performed with the aim of cataloguing predicted pathogenic PALB2 variants in breast, ovary and pancreas cancers. All catalogued predicted pathogenic variants are analysed to assess for overlap and mutational "hotspots" within gene exons. Our results showed that 911 (92.5%) cases were described in breast cancer patients, 49 (5.0%) cases were described in ovarian cancer patients, and 24 (2.4%) cases were described in pancreatic cancer patients. The top five most frequently reported predicted pathogenic PALB2 variants were c.509_510delGA, c.3113G > A, c.1592delT, c.172_175delTTGT, and c.1240C > T, accounting for 57.3% of all cases. Breast and pancreatic cancers share five variants while breast and ovarian cancers share 12 variants. Breast, ovarian and pancreatic cancers share eight common variants. Exons with the highest mutation rates were exons 2 (6.7%), 1 (6.3%) and 3 (5.8%). This systematic review provides a quantitative catalogue of predicted pathogenic PALB2 variants described in cancers. This comprehensive analysis of the PALB2 mutational spectrum represents a useful resource for clinicians overseeing PALB2-related cancer surveillance and provides a valuable resource for future PALB2-specific research.


Assuntos
Neoplasias da Mama/genética , Carcinoma Epitelial do Ovário/genética , Proteína do Grupo de Complementação N da Anemia de Fanconi/genética , Neoplasias Ovarianas/genética , Neoplasias Pancreáticas/genética , Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias da Mama/patologia , Carcinoma Epitelial do Ovário/patologia , Éxons/genética , Feminino , Predisposição Genética para Doença , Mutação em Linhagem Germinativa , Humanos , Neoplasias Ovarianas/patologia , Neoplasias Pancreáticas/patologia
4.
Pancreas ; 46(10): 1314-1321, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28902764

RESUMO

OBJECTIVES: The aims of this study were to (i) identify independent predictors of survival after pancreaticoduodenectomy for ampullary cancer and (ii) develop a prognostic model of survival. METHODS: Data were analyzed retrospectively on 110 consecutive patients who underwent pancreaticoduodenectomy between 2002 and 2013. Subjects were categorized into 3 nodal subgroups as per the recently proposed nodal subclassification: N0 (node negative), N1 (1-2 metastatic nodes), or N2 (≥3 metastatic nodes). Clinicopathological features and overall survival were compared by Kaplan-Meier and Cox regression analyses. RESULTS: The overall 1-, 3-, and 5-year survival rates were 79.8%, 42.2%, and 34.9%, respectively. The overall 1-, 3-, and 5-year survival rates for the N0 group were 85.2%, 71.9%, and 67.4%, respectively. The 1-, 3-, 5-year survival rates for the N1 and N2 subgroups were 81.5%, 49.4%, and 49.4% and 75%, 19.2%, and 6.4%, respectively (log rank, P < 0.0001). After performing a multivariate Cox regression analysis, vascular invasion and lymph node ratio were the only independent predictors of survival. Hence, a prediction model of survival was constructed based on those 2 variables. CONCLUSIONS: Using data from a carefully selected cohort of patients, we created a pilot prognostic model of postresectional survival. The proposed model may help clinicians to guide treatments in the adjuvant setting.


Assuntos
Ampola Hepatopancreática/cirurgia , Neoplasias do Ducto Colédoco/cirurgia , Neoplasias Pancreáticas/cirurgia , Pancreaticoduodenectomia/métodos , Modelos de Riscos Proporcionais , Adulto , Idoso , Idoso de 80 Anos ou mais , Ampola Hepatopancreática/patologia , Neoplasias do Ducto Colédoco/patologia , Feminino , Humanos , Estimativa de Kaplan-Meier , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Neoplasias Pancreáticas/patologia , Projetos Piloto , Prognóstico , Estudos Retrospectivos
5.
Pancreatology ; 15(2): 179-84, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25579809

RESUMO

BACKGROUND: Post-operative pancreatic fistula (POPF) is the major source of morbidity following pancreaticoduodenectomy. A predictive indicator would be highly advantageous. One potential marker is drain amylase concentration (DAC). However, its predictive value has not been fully established. METHODS: 405 patients undergoing pancreaticoduodenectomy at our centre over a 10 year period were reviewed to determine the value of DAC as a predictive indicator for the development of POPF. RESULTS: POPF developed in 58 patients (14%). These patients suffered greater morbidity. Overall 30-day mortality was 1.5%. Male gender (OR: 5.1; p = 0.0082) and age > 70 (OR 2; p = 0.0372) were independent risk factors for POPF, whilst Type 2 diabetes (OR: 0.2321; p = 0.0090) and pancreatic ductal-adenocarcinoma (OR: 0.3721; p = 0.0039) decreased POPF risk. The DACs post-operatively were significantly higher in those developing POPF, but with significant overlap. ROC curves revealed optimal threshold values for differentiating POPF and non-POPF patients. A DAC°<°1400 U/ml on day 1 and <768 U/ml on day 2, although having a poor positive predictive value (32-44%), had a very strong negative predictive value (97-99%). CONCLUSION: Our data suggest that post-operative DAC below the determined optimal threshold values on day 1 and 2 following pancreaticoduodenectomy carries high negative predictive value for POPF development and identifies patients in whom early drain removal, and enhanced recovery may be considered, with simultaneous assessment of operative and clinical factors.


Assuntos
Amilases/análise , Fístula Pancreática/enzimologia , Fístula Pancreática/etiologia , Pancreaticoduodenectomia/efeitos adversos , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/etiologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Carcinoma Ductal Pancreático/complicações , Carcinoma Ductal Pancreático/cirurgia , Drenagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fístula Pancreática/epidemiologia , Neoplasias Pancreáticas/complicações , Neoplasias Pancreáticas/cirurgia , Cuidados Pós-Operatórios , Complicações Pós-Operatórias/epidemiologia , Valor Preditivo dos Testes , Fatores de Risco , Fatores Sexuais , Resultado do Tratamento , Adulto Jovem
6.
Mol Oncol ; 8(2): 161-8, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24268522

RESUMO

Chromosomal instability is a hallmark of human cancer cells, but its role in carcinogenesis remains poorly resolved. Insights into this role have emerged from studies on the tumour suppressor BRCA2, whose inactivation in human cancers causes chromosomal instability through the loss of essential functions of the BRCA2 protein in the normal mechanisms responsible for the replication, repair and segregation of DNA during cell division. Humans who carry heterozygous germline mutations in the BRCA2 gene are highly predisposed to cancers of the breast, ovary, pancreas, prostate and other tissues. Here, we review recent studies that describe genetically engineered mouse models (GEMMs) for pancreatic cancer associated with BRCA2 mutations. These studies not only surprisingly show that BRCA2 does not follow the classical Knudson "two hit" paradigm for tumour suppression, but also highlight features of the interplay between TP53 inactivation and carcinogenesis in the context of BRCA2 deficiency. Thus, the models reveal novel aspects of cancer evolution in carriers of germline BRCA2 mutations, provide new insights into the tumour suppressive role of BRCA2, and establish valuable new preclinical settings for testing approaches to pancreatic cancer therapy; together, these features emphasize the value of GEMMs in cancer research.


Assuntos
Proteína BRCA2/metabolismo , Instabilidade Cromossômica , Cromossomos Humanos/metabolismo , Mutação em Linhagem Germinativa , Neoplasias Experimentais/metabolismo , Neoplasias Pancreáticas/metabolismo , Animais , Proteína BRCA2/genética , Transformação Celular Neoplásica , Cromossomos Humanos/genética , Reparo do DNA , Replicação do DNA/genética , DNA de Neoplasias/genética , DNA de Neoplasias/metabolismo , Humanos , Camundongos , Neoplasias Experimentais/genética , Neoplasias Experimentais/patologia , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia
7.
J Gastrointest Surg ; 17(10): 1869-82, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23835731

RESUMO

INTRODUCTION: Hepatic adenomas (HAs) are benign tumors of the liver, which can be solitary or multiple, and have a definite risk of malignant degeneration. DISCUSSION: The pathogenesis and natural history of this disease entity were previously unknown. Recent research into the molecular pathogenesis of this condition has provided evidence for the malignant transformation of some of these adenomas. In the current article, we discuss the current evidence on the molecular biology underlying malignant transformation of hepatic adenomas and the implications for the surgical management of this disease.


Assuntos
Adenoma/genética , Adenoma/cirurgia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/cirurgia , Adenoma/epidemiologia , Transformação Celular Neoplásica , Árvores de Decisões , Genótipo , Humanos , Neoplasias Hepáticas/epidemiologia , Fenótipo , Fatores de Risco
8.
Surgeon ; 10(5): 267-72, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22959160

RESUMO

BACKGROUND: Laparoscopic adrenalectomy (LA) is the gold standard for benign adrenal resection, and has been performed at our centre since 2000. We present a retrospective audit of our ten-year experience, and discuss the learning curve. METHODS: Creating a retrospective database, clinical and outcome data were collected for all resections performed over a ten-year period (2000-2010). Patients were chronologically divided into an 'early' (first 40 cases) and 'late' (subsequent cases) group to provide an insight into the learning curve. RESULTS: Over this period, 134 laparoscopic resections were performed, predominantly for benign adenomas (80.3%), with 48% of patients having primary hyperaldosteronism. There was almost equal sex distribution and mean age was 50.2 years, with a median BMI of 28.2. The mean operating time for left and right procedures were 127 and 124 min respectively, with 56.7% of resections being left sided. Our rate of conversion to open was 3.9%. Median length of stay was 4 days post-operatively. There was no mortality and 8.7% patients experienced a surgical complication. Analysis of the grouped data demonstrated a statistically significant reduction in open conversion rate (p = 0.017) and operative time (p = 0.011) in the 'late' group. Among the two groups there was no statistically significant difference in the length of stay and surgical complication rate. All results were comparable to published series in the literature. CONCLUSION: LA has proven to be a safe procedure with a low complication rate at our centre. Our data provide evidence that operative time and conversion rate improves with experience.


Assuntos
Adenoma/cirurgia , Neoplasias das Glândulas Suprarrenais/cirurgia , Adrenalectomia/métodos , Laparoscopia/métodos , Feocromocitoma/cirurgia , Adolescente , Adulto , Idoso , Feminino , Humanos , Curva de Aprendizado , Tempo de Internação , Masculino , Auditoria Médica , Pessoa de Meia-Idade , Adulto Jovem
9.
Int J Surg Case Rep ; 3(11): 555-8, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22922358

RESUMO

INTRODUCTION: Portal venous aneurysms are a rare finding. The reported incidence is on the rise with increasing use of modern imaging techniques in clinical practice. However, there is still much to be elicited regarding their aetiology, natural history, and management. PRESENTATION OF CASE: An 80-year-old woman presented with abdominal pain and nausea. Investigations showed a hypoechoic area in the region of the head of pancreas on ultrasound, which was found to be a portal venous aneurysm on CT. In view of her multiple comorbidities, a conservative approach was taken. DISCUSSION: Portal venous aneurysms represent approximately 3% of all venous aneurysms with a reported prevalence of 0.43%. They may be congenital, due to failure of complete regression of the right vitelline vein, or acquired secondary to portal hypertension. The primary presentation of portal vein aneurysm is abdominal pain, followed by incidental detection on imaging, with a minority of patients presenting with gastrointestinal bleeding. Complications of PVA include thrombosis, biliary tract obstruction, inferior vena cava obstruction, and duodenal compression. On the whole PVAs are stable and have a low risk of complications with 88% of patients showing no progression of aneurysm size or complications on subsequent follow up scans. CONCLUSION: We recommend that portal venous aneurysms be assessed using colour Doppler ultrasonography in the first instance with CT scans reserved for indeterminate cases or symptomatic patients. Due to the slow progression of such aneurysms, surgery is recommended only for symptomatic patients or those with complications secondary to portal venous aneurysms.

11.
Ann R Coll Surg Engl ; 92(7): 562-8, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20522309

RESUMO

INTRODUCTION: The risk of ipsilateral breast tumour recurrence (IBTR) following breast conservation surgery (BCS) for invasive breast cancer (IBC) and radiotherapy is dependent on patient-, tumour- and treatment-related variables. In the Cambridge Breast Unit, breast conserving surgery has been performed with a target radial margin of 5 mm for IBC, in combination with 40-Gy hypofractionated (15 fractions) breast radiotherapy, since 1999. PATIENTS AND METHODS: An audit was performed of cases treated between 1999 and 2004. A total of 563 patients underwent BCS for invasive breast cancer with 90.4% receiving radiotherapy (RT) and 60.4% of patients receiving boost RT (3 fractions of 3-Gy). RESULTS: After a median follow-up of 58 months, five of the 563 (0.9%) patients developed IBTR. The 5-year actuarial IBTR rate was 1.1%. In terms of distant disease recurrence (DDR), 29 of the 563 (5.2%) had DDR during follow-up, giving a 5-year actuarial DDR rate of 5.4%. The 5-year breast cancer specific survival was 95%, with the poorer NPI groups having worse breast cancer specific survival (Log-rank, P<0.0001). More importantly, patients with IBTR had a shorter breast cancer-specific survival than those who were IBTR-free (Log-rank, P<0.0001). CONCLUSIONS: Our treatment regimen, combining BCS with a 5-mm target margin and hypofractionated 40-Gy RT, results in an extremely low rate of IBTR, and compares favourably with the target IBTR rate of <5% defined by the Association of Breast Surgeons (ABS) at BASO guidelines.


Assuntos
Neoplasias da Mama/cirurgia , Mastectomia Segmentar/métodos , Recidiva Local de Neoplasia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/patologia , Neoplasias da Mama/radioterapia , Métodos Epidemiológicos , Feminino , Humanos , Mastectomia Segmentar/normas , Pessoa de Meia-Idade , Invasividade Neoplásica , Prognóstico , Radioterapia Adjuvante , Resultado do Tratamento
13.
Clin J Gastroenterol ; 2(1): 22-26, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26191803

RESUMO

Pneumatosis intestinalis (PI) is a condition characterised by gas-filled cystic malformations on the intestinal wall. It is often secondary to an underlying disease process. We describe the case of a 76-year-old gentleman who presented with intermittent abdominal pain, altered bowel habits and weight loss. Barium enema was unremarkable, apart from sigmoid diverticulosis. CT scan found evidence of pneumatosis on small bowel walls with benign pneumoperitoneum. As there was no sign of intra-abdominal crisis, he was initially treated conservatively. Unfortunately, he required re-admission 6 weeks later with symptoms of bowel obstruction and clinical signs of perotinitis. At laparotomy, he was found to have extensive small bowel infarction due to volvulus from 'twisting' around the axis of superior mesenteric vessels. Evidently, this occurred secondary to a congenitally long small bowel mesentery that predisposed him to volvulus. Extensive small bowel resection was performed. The postoperative course was complicated by persistent hypotension, which proved fatal. This case report draws attention to the rare association between PI and small bowel volvulus predisposed by a congenitally long mesentery, which can present initially with a benign picture (intermittent, reversible volvulus), but subsequently be complicated by lethal bowel infarction (irreversible volvulus). This case raises several issues about the management of this rare condition. Clinicians must realise that PI, though often benign, can present with lethal complications, and early recognition of such complications can be life-saving.

14.
Clin J Gastroenterol ; 2(3): 238-241, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26192304

RESUMO

Cholecysto-duodenal fistula and gallstone ileus are well-recognised complications of gallstone disease. However, small bowel necrosis is a rare complication of gallstone disease. We describe a case of gallstone-induced ileal necrosis presenting with symptoms and signs resembling acute appendicitis. A 79-year-old woman presented to the surgical team with central abdominal pain which subsequently shifted to the right iliac fossa. Clinically, the patient had localised perotinism in the right iliac fossa with high inflammatory markers. Abdominal radiography showed no diagnostic features. Initial clinical impression was that of acute appendicitis. Given that this diagnosis was unlikely in a patient of this age, an abdominal CT scan was performed. The CT scan showed evidence of a large gallstone causing small bowel obstruction in the presence of a cholecysto-duodenal fistula. At surgery, she was found to have an area of necrosis with a pin-point perforation at the site of impaction of the gallstone in the proximal ileum. This occurred secondarily to pressure necrosis from the gallstone impacting at a site where the small bowel diameter narrows in transition from jejunum to ileum. A limited small bowel resection was performed with an uncomplicated postoperative course. This case report draws attention to a rare complication of gallstone disease which presents with a clinical picture similar to acute appendicitis. Preoperative investigation for an elderly patient who presents with an acute abdomen should include an abdominal CT scan to diagnose any rare disease processes which otherwise may not be suspected.

15.
Surg Clin North Am ; 88(4): 681-704, v, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18672136

RESUMO

Contemporary ideas of carcinogenesis envisage a series of stochastic genetic changes that confer a selective growth advantage over healthy cells. These changes collectively lead to the disruption of coordinated networks of intercellular communication and cause a fundamental change in cellular behavior, which affects processes, such as proliferation, differentiation, and apoptosis. This progressive dysregulation of cellular function implies that cancer is not a morphologic entity, but a process in which the malignant phenotype is gradually acquired.


Assuntos
Biomarcadores Tumorais/genética , Genes Neoplásicos/genética , Neoplasias/genética , Neoplasias/cirurgia , Predisposição Genética para Doença , Humanos
17.
Cancer ; 113(2): 302-14, 2008 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-18473350

RESUMO

BACKGROUND: High mobility group AT-hook 1 (HMGA1) proteins are architectural transcription factors that are overexpressed by pancreatic adenocarcinomas. The authors hypothesized that tumor HMGA1 status represents a novel prognostic marker in pancreatic adenocarcinoma. They also tested the hypothesis that HMGA1 promotes anchorage-independent cellular proliferation and in vivo tumorigenicity. METHODS: Tumor HMGA1 expression was examined by immunohistochemical analysis of tissues from 89 consecutive patients who underwent resection for pancreatic adenocarcinoma. Short-hairpin RNA (shRNA)-mediated RNA interference was used to silence HMGA1 expression in MiaPaCa2 and PANC1 pancreatic cancer cells. Anchorage-independent proliferation was assessed by using soft agar assays. The roles of phosphatidylinositol 3-kinase (PI3-K)/Akt and extracellular signal-regulated kinase (ERK) signaling were investigated by using specific inhibitors and adenoviral dominant-negative/active Akt constructs. In vivo tumorigenicity was assessed by using a nude mouse xenograft model. RESULTS: Tumor HMGA1 expression was detected in 93% of patients with pancreatic adenocarcinoma. Patients with HMGA1-negative tumors had a significantly longer median survival than patients with HMGA1-expressing cancers in univariate analysis (P = .0028) and in multivariate analysis (P<.05). shRNA-mediated HMGA1 silencing resulted in significant reductions in anchorage-independent proliferation in soft agar. Forced HMGA1 overexpression promoted proliferation in soft agar through a process that was dependent on PI3-K/Akt-activited signaling, but not on mitogen-activated protein kinase (MEK)/ERK signaling. Targeted silencing of HMGA1 reduced tumor growth in vivo through reduced proliferation (Ki-67 index) and increased apoptosis (terminal deoxynucleotidyl transferase nick-end labeling). CONCLUSIONS: The current findings suggested that HMGA1 is an independent predictor of poor postoperative survival in patients with pancreatic adenocarcinoma. Furthermore, HMGA1 promotes tumorigenicity through a PI3-K/Akt-dependent mechanism. HMGA1 warrants further evaluation as a prognostic marker and therapeutic target in pancreatic cancer.


Assuntos
Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Proteína HMGA1a/metabolismo , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Adenocarcinoma/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Linhagem Celular Tumoral , Proliferação de Células , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Proteína HMGA1a/genética , Humanos , Masculino , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Neoplasias Pancreáticas/genética , Fosfatidilinositol 3-Quinases/metabolismo , Prognóstico , Proteínas Proto-Oncogênicas c-akt/metabolismo , Interferência de RNA , Taxa de Sobrevida , Ensaios Antitumorais Modelo de Xenoenxerto
18.
Clin Cancer Res ; 14(5): 1470-7, 2008 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-18316571

RESUMO

PURPOSE: HMGA1 proteins are architectural transcription factors that are overexpressed by pancreatic adenocarcinomas. We previously have shown that RNA interference targeting the HMGA1 gene may represent a potential chemosensitizing strategy in pancreatic adenocarcinoma cells. In this study, we tested the hypothesis that HMGA1 promotes chemoresistance to gemcitabine in pancreatic cancer cells. EXPERIMENTAL DESIGN AND RESULTS: Stable short hairpin RNA-mediated HMGA1 silencing in BxPC3 and MiaPaCa2 cells promoted chemosensitivity to gemcitabine, with reductions in gemcitabine IC(50) and increases in gemcitabine-induced apoptosis and caspase-3 activation. In contrast, forced HMGA1 overexpression in MiaPaCa2 cells promoted chemoresistance to gemcitabine, with increases in gemcitabine IC(50) and reductions in gemcitabine-induced apoptosis and caspase-3 activation. Dominant negative Akt abrogated HMGA1 overexpression-induced increases in chemoresistance to gemcitabine. Finally, HMGA1 silencing promoted chemosensitivity to gemcitabine in vivo in a nude mouse xenograft model of pancreatic adenocarcinoma. CONCLUSION: Our findings suggest that HMGA1 promotes chemoresistance to gemcitabine through an Akt-dependent mechanism. Targeted therapies directed at HMGA1 represent a potential strategy for ameliorating chemoresistance in pancreatic adenocarcinoma.


Assuntos
Adenocarcinoma/tratamento farmacológico , Antimetabólitos Antineoplásicos/uso terapêutico , Carcinoma Ductal Pancreático/tratamento farmacológico , Desoxicitidina/análogos & derivados , Resistencia a Medicamentos Antineoplásicos , Proteína HMGA1a/metabolismo , Neoplasias Pancreáticas/tratamento farmacológico , Adenocarcinoma/secundário , Animais , Apoptose/efeitos dos fármacos , Western Blotting , Carcinoma Ductal Pancreático/secundário , Caspase 3/metabolismo , Células Cultivadas , Desoxicitidina/uso terapêutico , Ativação Enzimática/efeitos dos fármacos , Proteína HMGA1a/antagonistas & inibidores , Proteína HMGA1a/genética , Humanos , Técnicas Imunoenzimáticas , Masculino , Camundongos , Camundongos Nus , Neoplasias Pancreáticas/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Interferência de RNA , Transdução de Sinais/efeitos dos fármacos , Células Tumorais Cultivadas , Gencitabina
19.
J Med Case Rep ; 1: 36, 2007 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-17598918

RESUMO

BACKGROUND: A carcinoma within a hernia in the groin is uncommon, with an incidence of less than 0.5 percent of all excised sacs. This article describes a case of synchronous colonic carcinomas, one of which presented as an inguinoscrotal mass. CASE PRESENTATION: A 69-year old man presented with a large, irreducible left inguinoscrotal hernia and symptoms of obstruction. On examination, there was an 8 cm palpable mass within the hernia sac. CT scan revealed small and proximal large bowel obstruction secondary to a large ingunoscrotal sac and synchronous colonic tumours of the transverse colon and the ascending colon. The former presented as an inguinoscrotal mass. Laparotomy revealed a large tumour mass arising from the transverse colon in the hernia sac. The procedure was followed by an extended right hemicolectomy, during which the second tumour in the ascending colon was also resected. CONCLUSION: This case demonstrates a rare but interesting occurrence of primary transverse colon carcinoma presenting in a hernia sac, in conjunction with a synchronous tumour of the ascending colon. Prognosis is comparable to patients with a solitary tumour of similar pathological staging when the resection is curative. The presence of an inguinal hernia itself does not signify an increased risk of colorectal malignancy. However, in the presence of obstruction, incarceration, and weight loss, malignancy should be suspected. Thorough clinical examination, flexible sigmoidoscopy or radiographic evaluation is necessary preoperatively in such patients. Surgical resection, with or without adjuvant oncological treatment, should be performed as soon as possible, using established techniques with modifications according to involvement of local structures.

20.
Cancer Res ; 66(24): 11613-22, 2006 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-17178855

RESUMO

HMGA1 proteins are architectural transcription factors that are overexpressed in a range of human malignancies, including pancreatic adenocarcinoma. We hypothesized that HMGA1 expression is a determinant of cellular invasiveness and metastasis in pancreatic cancer. Stable silencing of HMGA1 in MiaPaCa2 and PANC1 pancreatic adenocarcinoma cells was achieved by transfection of short hairpin RNA-generating vectors. Additionally, stable overexpression of HMGA1 in MiaPaCa2 cells (characterized by low levels of inherent HMGA1 expression) was achieved. HMGA1 silencing resulted in significant reductions in cellular invasiveness through Matrigel; in cellular matrix metalloproteinase-9 (MMP-9) activity, mRNA levels, and gene promoter activity; and in Akt phosphorylation at Ser(473). Conversely, forced HMGA1 overexpression resulted in significant increases in cellular invasiveness; in cellular MMP-9 activity, mRNA levels, and promoter activity; and in Akt phosphorylation at Ser(473). HMGA1 overexpression-induced increases in invasiveness were MMP-9 dependent. The role of phosphatidylinositol-3 kinase (PI3K)/Akt in mediating HMGA1-dependent invasiveness was elucidated by a specific PI3K inhibitor (LY294002) and constitutively active and dominant-negative Akt adenoviral constructs. Akt-dependent modulation of MMP-9 activity contributed significantly to HMGA1 overexpression-induced increases in invasive capacity. Furthermore, HMGA1 silencing resulted in reductions in metastatic potential and tumor growth in vivo and in tumoral MMP-9 activity. Our findings suggest that HMGA1 may be a novel molecular determinant of invasiveness and metastasis, as well as a potential therapeutic target, in pancreatic adenocarcinoma.


Assuntos
Adenocarcinoma/patologia , Proteína HMGA1a/genética , Neoplasias Pancreáticas/patologia , Sequência de Bases , Divisão Celular , Linhagem Celular Tumoral , Primers do DNA , Genes Reporter , Vetores Genéticos , Humanos , Metaloproteinase 9 da Matriz/genética , Invasividade Neoplásica , Neoplasias Pancreáticas/genética , Reação em Cadeia da Polimerase , Regiões Promotoras Genéticas , Interferência de RNA , Transfecção
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