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1.
J Clin Oncol ; 42(2): 146-156, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-37906724

RESUMO

PURPOSE: In patients with peritoneal metastasis (PM) from gastric cancer (GC), chemotherapy is the treatment of choice. Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) are still being debated. This randomized, controlled, open-label, multicenter phase III trial (EudraCT 2006-006088-22; ClinicalTrials.gov identifier: NCT02158988) explored the impact on overall survival (OS) of HIPEC after CRS. PATIENTS AND METHODS: Adult patients with GC and histologically proven PM were randomly assigned (1:1) to perioperative chemotherapy and CRS alone (CRS-A) or CRS plus HIPEC (CRS + H). HIPEC comprised mitomycin C 15 mg/m2 and cisplatin 75 mg/m2 in 5 L of saline perfused for 60 minutes at 42°C. The primary end point was OS; secondary endpoints included progression-free survival (PFS), other distant metastasis-free survival (MFS), and safety. Analyses followed the intention-to-treat principle. RESULTS: Between March 2014 and June 2018, 105 patients were randomly assigned (53 patients to CRS-A and 52 patients to CRS + H). The trial stopped prematurely because of slow recruitment. In 55 patients, treatment stopped before CRS mainly due to disease progression/death. Median OS was the same for both groups (CRS + H, 14.9 [97.2% CI, 8.7 to 17.7] months v CRS-A, 14.9 [97.2% CI, 7.0 to 19.4] months; P = .1647). The PFS was 3.5 months (95% CI, 3.0 to 7.0) in the CRS-A group and 7.1 months (95% CI, 3.7 to 10.5; P = .047) in the CRS + H group. The CRS + H group showed better MFS (10.2 months [95% CI, 7.7 to 14.7] v CRS-A, 9.2 months [95% CI, 6.8 to 11.5]; P = .0286). The incidence of grade ≥3 adverse events (AEs) was similar between groups (CRS-A, 38.1% v CRS + H, 43.6%; P = .79). CONCLUSION: This study showed no OS difference between CRS + H and CRS-A. PFS and MFS were significantly better in the CRS + H group, which needs further exploration. HIPEC did not increase AEs.


Assuntos
Hipertermia Induzida , Neoplasias Peritoneais , Neoplasias Gástricas , Adulto , Humanos , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/cirurgia , Neoplasias Peritoneais/tratamento farmacológico , Neoplasias Peritoneais/secundário , Quimioterapia Intraperitoneal Hipertérmica , Terapia Combinada , Procedimentos Cirúrgicos de Citorredução/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Taxa de Sobrevida , Estudos Retrospectivos
3.
Cancers (Basel) ; 13(5)2021 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-33800365

RESUMO

Molecular precision oncology faces two major challenges: first, to identify relevant and actionable molecular variants in a rapidly changing field and second, to provide access to a broad patient population. Here, we report a four-year experience of the Molecular Tumor Board (MTB) of the Comprehensive Cancer Center Freiburg (Germany) including workflows and process optimizations. This retrospective single-center study includes data on 488 patients enrolled in the MTB from February 2015 through December 2018. Recommendations include individual molecular diagnostics, molecular stratified therapies, assessment of treatment adherence and patient outcomes including overall survival. The majority of MTB patients presented with stage IV oncologic malignancies (90.6%) and underwent an average of 2.1 previous lines of therapy. Individual diagnostic recommendations were given to 487 patients (99.8%). A treatment recommendation was given in 264 of all cases (54.1%) which included a molecularly matched treatment in 212 patients (43.4%). The 264 treatment recommendations were implemented in 76 patients (28.8%). Stable disease was observed in 19 patients (25.0%), 17 had partial response (22.4%) and five showed a complete remission (6.6%). An objective response was achieved in 28.9% of cases with implemented recommendations and for 4.5% of the total population (22 of 488 patients). By optimizing the MTB workflow, case-discussions per session increased significantly while treatment adherence and outcome remained stable over time. Our data demonstrate the feasibility and effectiveness of molecular-guided personalized therapy for cancer patients in a clinical routine setting showing a low but robust and durable disease control rate over time.

4.
Dtsch Med Wochenschr ; 146(4): 213, 2021 02.
Artigo em Alemão | MEDLINE | ID: mdl-33592656
5.
Dtsch Med Wochenschr ; 146(4): 229-236, 2021 02.
Artigo em Alemão | MEDLINE | ID: mdl-33592658

RESUMO

Acute pancreatitis is one of the most common gastrointestinal diseases requiring acute hospitalization and its incidence is increasing. A particular challenge is the prediction and treatment of severe cases, which only affect a minority of patients, but are associated with mortality rates of up to 30 percent. In this review, we consider the diagnostic evaluation of the disease and provide an overview of current conservative and interventional treatment strategies.


Assuntos
Pancreatite , Humanos , Incidência
6.
Cancers (Basel) ; 12(11)2020 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-33121007

RESUMO

CAP7.1 is a novel topoisomerase II inhibitor, converted to active etoposide via carboxylesterase 2 (CES2), with signals of efficacy in treatment-refractory solid tumours. In a Phase II trial, 27 patients with advanced biliary tract cancers (BTC) were randomised 1:1 to CAP7.1 plus best supportive care (BSC), or BSC alone, with crossover to CAP7.1 upon disease progression. The primary objective was disease control rate (DCR) following 28-day cycles of CAP7.1 (200/150 mg/m2; iv), or BSC until progression. Secondary objectives included progression-free survival (PFS), time-to-treatment failure (TTF), overall survival (OS) and safety. Fourteen patients received CAP7.1 and 13 BSC. DCR favoured CAP7.1 vs. BSC (50% vs. 20%; treatment difference: 30%, 95%CI -18.44, 69.22, full analysis set [FAS]), with disease progression in 40% vs. 70%, respectively. Significantly longer median PFS was achieved for CAP7.1 vs. BSC: 66 vs. 39 days, respectively (hazard ratio [HR] 0.31; 95%CI 0.11, 0.86; p = 0.009; FAS). Similar trends were observed for TTF and OS. CES2-positive patients had longer median PFS (158 vs. 56 days) and OS (228 vs. 82 days) vs. CES2-negative patients. Adverse events were predictable, dose-dependent and consistent with those previously observed with etoposide. These efficacy and safety findings in second-line BTC warrant further clinical investigation of CAP7.1.

7.
Blood ; 136(12): 1442-1455, 2020 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-32542357

RESUMO

Acute graft-versus-host disease (GVHD) is a life-threatening complication after allogeneic hematopoietic cell transplantation (allo-HCT). Although currently used GVHD treatment regimens target the donor immune system, we explored here an approach that aims at protecting and regenerating Paneth cells (PCs) and intestinal stem cells (ISCs). Glucagon-like-peptide-2 (GLP-2) is an enteroendocrine tissue hormone produced by intestinal L cells. We observed that acute GVHD reduced intestinal GLP-2 levels in mice and patients developing GVHD. Treatment with the GLP-2 agonist, teduglutide, reduced de novo acute GVHD and steroid-refractory GVHD, without compromising graft-versus-leukemia (GVL) effects in multiple mouse models. Mechanistically GLP-2 substitution promoted regeneration of PCs and ISCs, which enhanced production of antimicrobial peptides and caused microbiome changes. GLP-2 expanded intestinal organoids and reduced expression of apoptosis-related genes. Low numbers of L cells in intestinal biopsies and high serum levels of GLP-2 were associated with a higher incidence of nonrelapse mortality in patients undergoing allo-HCT. Our findings indicate that L cells are a target of GVHD and that GLP-2-based treatment of acute GVHD restores intestinal homeostasis via an increase of ISCs and PCs without impairing GVL effects. Teduglutide could become a novel combination partner for immunosuppressive GVHD therapy to be tested in clinical trials.


Assuntos
Peptídeo 2 Semelhante ao Glucagon/uso terapêutico , Doença Enxerto-Hospedeiro/tratamento farmacológico , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Intestinos/efeitos dos fármacos , Celulas de Paneth/efeitos dos fármacos , Peptídeos/uso terapêutico , Células-Tronco/efeitos dos fármacos , Animais , Feminino , Fármacos Gastrointestinais/uso terapêutico , Doença Enxerto-Hospedeiro/patologia , Humanos , Intestinos/citologia , Intestinos/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Celulas de Paneth/patologia , Células-Tronco/patologia , Transplante Homólogo/efeitos adversos
8.
Scand J Gastroenterol ; 54(10): 1189-1198, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31608788

RESUMO

Background: Although lichen planus (LP) is a common skin disorder, the prevalence of esophageal involvement (ELP) and its clinical manifestations are poorly defined. We aimed to establish diagnostic criteria and characterize disease outcomes of ELP.Methods: Clinical, endoscopic, histological, and immunofluorescence data from consecutive patients with known LP between 2013 and 2018 were analyzed. We established endoscopic (denudation and tearing of the mucosa, hyperkeratosis and trachealization) and histological criteria (mucosal detachment, T-lymphocytic infiltrate, intraepithelial apoptosis, dyskeratosis, and fibrinogen deposits along the basement membrane) to grade disease severity. Endoscopic findings were correlated with clinical symptoms. Response to medical therapy was monitored.Results: Fifty-two consecutive patients (median age 59.5 years) were analyzed. According to our grading system, 16 patients were considered as severe and 18 as mild ELP. Dysphagia was the only symptom which differentiated patients with severe (14/16) or mild ELP (8/18) from patients without ELP (1/18). Concomitant oral and genital involvement of LP was associated with the presence of ELP, while oral involvement alone was not. Follow-up of 14/16 patients with severe EPL for at least one year revealed that most of these patients responded to topical corticosteroids (budesonide: n = 9/10 or fluticasone n = 2/2). Three budesonide patients experienced a resolution of symptomatic esophageal stenosis.Conclusions: Esophageal involvement of LP is frequent, but may be asymptomatic. ELP can be diagnosed using the diagnostic criteria proposed here. Dysphagia and combined oral and genital manifestation are associated with ELP. Therapy with topical corticosteroids appears to be a prudent therapeutic approach for ELP.


Assuntos
Doenças do Esôfago/diagnóstico , Líquen Plano/diagnóstico , Corticosteroides/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Anti-Inflamatórios/uso terapêutico , Doenças do Esôfago/tratamento farmacológico , Doenças do Esôfago/patologia , Esofagoscopia , Feminino , Seguimentos , Humanos , Imunossupressores/uso terapêutico , Líquen Plano/tratamento farmacológico , Líquen Plano/patologia , Masculino , Pessoa de Meia-Idade , Diagnóstico Ausente/prevenção & controle , Índice de Gravidade de Doença , Resultado do Tratamento
9.
Dev Dyn ; 247(6): 854-866, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29532564

RESUMO

BACKGROUND: The plasticity of pancreatic acinar cells to undergo acinar to ductal metaplasia (ADM) has been demonstrated to contribute to the regeneration of the pancreas in response to injury. Sox9 is critical for ductal cell fate and important in the formation of ADM, most likely in concert with a complex hierarchy of, as yet, not fully elucidated transcription factors. RESULTS: By using a mouse model of acute pancreatitis and three dimensional organoid culture of primary pancreatic ductal cells, we herein characterize the Ets-transcription factor Etv5 as a pivotal regulator of ductal cell identity and ADM that acts upstream of Sox9 and is essential for Sox9 expression in ADM. Loss of Etv5 is associated with increased severity of acute pancreatitis and impaired ADM formation leading to delayed tissue regeneration and recovery in response to injury. CONCLUSIONS: Our data provide new insights in the regulation of ADM with implications in our understanding of pancreatic homeostasis, pancreatitis and epithelial plasticity. Developmental Dynamics 247:854-866, 2018. © 2018 Wiley Periodicals, Inc.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Ductos Pancreáticos/metabolismo , Ductos Pancreáticos/fisiologia , Pancreatite/metabolismo , Fatores de Transcrição SOX9/metabolismo , Fatores de Transcrição/metabolismo , Células Acinares/citologia , Células Acinares/metabolismo , Animais , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Células Cultivadas , Proteínas de Ligação a DNA/genética , Camundongos , Camundongos Knockout , Pâncreas/embriologia , Pâncreas/metabolismo , Pancreatite/genética , Fatores de Transcrição SOX9/genética , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Fatores de Transcrição/genética
10.
Artigo em Inglês | MEDLINE | ID: mdl-32913998

RESUMO

PURPOSE: Dramatic advances in our understanding of the molecular pathophysiology of cancer, along with a rapidly expanding portfolio of molecular targeted drugs, have led to a paradigm shift toward personalized, biomarker-driven cancer treatment. Here, we report the 2-year experience of the Comprehensive Cancer Center Freiburg Molecular Tumor Board (MTB), one of the first interdisciplinary molecular tumor conferences established in Europe. The role of the MTB is to recommend personalized therapy for patients with cancer beyond standard-of-care treatment. METHODS: This retrospective case series includes 198 patients discussed from March 2015 through February 2017. The MTB guided individual molecular diagnostics, assessed evidence of actionability of molecular alterations, and provided therapy recommendations, including approved and off-label treatments as well as available matched clinical trials. RESULTS: The majority of patients had metastatic solid tumors (73.7%), mostly progressive (77.3%) after a mean of 2.0 lines of standard treatment. Diagnostic recommendations resulted in 867 molecular diagnostic tests for 172 patients (five per case), including exome analysis in 36 cases (18.2%). With a median turnaround time of 28 days, treatment recommendations were given to 104 patients (52.5%). These included single-agent targeted therapies (42.3%), checkpoint inhibitors (37.5%), and combination therapies (18.3%). Treatment recommendations were implemented in 33 of 104 patients (31.7%), of whom 19 (57.6%) showed stable disease or partial response, including 14 patients (7.1% of the entire population) receiving off-label treatments. CONCLUSION: Personalized extended molecular-guided patient care is effective for a small but clinically meaningful proportion of patients in challenging clinical situations. Limited access to targeted drugs, lack of trials, and submission at late disease stage prevents broader applicability, whereas genome-wide analyses are not a strict requirement for predictive molecular testing.

11.
Gastroenterology ; 151(3): 540-553.e14, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27318148

RESUMO

BACKGROUND & AIMS: The ETS-transcription factor ETV1 is involved in epithelial-mesenchymal transition during pancreatic development and is induced in mouse pancreatic intraepithelial neoplasia (PanIN) and pancreatic ductal adenocarcinoma (PDAC). We investigated the function of ETV1 in stromal expansion of PDAC and metastasis, as well as its effects on a novel downstream target Sparc, which encodes a matricellular protein found in PDAC stroma that has been associated with invasiveness, metastasis and poor patient outcomes. METHODS: Pancreatic ductal cells were isolated from Pdx1Cre;Kras(G12D/+) mice (PanIN), Pdx1Cre;Kras(G12D/+);p53(fl/+) and Pdx1Cre;Kras(G12D/+);p53(fl/+);Rosa26(YFP) mice (PDAC), and Pdx1Cre;Kras(G12D/+);p53(fl/+);Sparc(-/-) mice. Cells were grown in 3-dimensional organoid culture to analyze morphology, proliferation, and invasion. Human PanIN and PDAC tissues were evaluated for ETV1 expression. Orthotopic pancreatic transplants of ETV1-overexpressing PDAC and respective control cells were performed. RESULTS: ETV1 expression was significantly increased in human PanINs and, even more so, in primary and metastatic PDAC. Analyses of mouse orthotopic xenografts revealed that ETV1 induced significantly larger primary tumors than controls, with significantly increased stromal expansion, ascites and metastases. In 3-dimensional organoids, ETV1 disrupted cyst architecture, induced EMT, and increased invasive capacity. Furthermore, we identified Sparc as a novel functional gene target of Etv1 by luciferase assays, and SPARC and ETV1 proteins co-localized in vivo. Disruption of Sparc abrogates the phenotype of stromal expansion and metastasis found with ETV1 overexpression in vivo. We identified hyaluronan synthase 2 (Has2) as another novel downstream factor of Etv1; that may mediate ETV1's significant expansion of hyaluronic acid in PDAC stroma. Conversely, disruption of Etv1 in PDAC mice (Pdx1Cre;Kras(G12D/+);p53(fl/+);Rosa26(YFP);Cre;Etv1(fl/fl)) reduced levels of SPARC and hyaluronic acid in the stroma. CONCLUSIONS: ETV1 is critical in the desmoplastic stromal expansion and metastatic progression of pancreatic cancer in mice, mediated functionally in part through Sparc and Has2.


Assuntos
Carcinoma Ductal Pancreático/genética , Proteínas de Ligação a DNA/metabolismo , Ductos Pancreáticos/citologia , Neoplasias Pancreáticas/genética , Células Estromais/metabolismo , Fatores de Transcrição/metabolismo , Animais , Carcinoma Ductal Pancreático/patologia , Transição Epitelial-Mesenquimal/genética , Camundongos , Metástase Neoplásica/genética , Neoplasias Pancreáticas/patologia
12.
Genes Dev ; 30(2): 233-47, 2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26773005

RESUMO

The two major isoforms of the paired-related homeodomain transcription factor 1 (Prrx1), Prrx1a and Prrx1b, are involved in pancreatic development, pancreatitis, and carcinogenesis, although the biological role that these isoforms serve in the systemic dissemination of pancreatic ductal adenocarcinoma (PDAC) has not been investigated. An epithelial-mesenchymal transition (EMT) is believed to be important for primary tumor progression and dissemination, whereas a mesenchymal-epithelial transition (MET) appears crucial for metastatic colonization. Here, we describe novel roles for both isoforms in the metastatic cascade using complementary in vitro and in vivo models. Prrx1b promotes invasion, tumor dedifferentiation, and EMT. In contrast, Prrx1a stimulates metastatic outgrowth in the liver, tumor differentiation, and MET. We further demonstrate that the switch from Prrx1b to Prrx1a governs EMT plasticity in both mouse models of PDAC and human PDAC. Last, we identify hepatocyte growth factor ( HGF) as a novel transcriptional target of Prrx1b. Targeted therapy of HGF in combination with gemcitabine in a preclinical model of PDAC reduces primary tumor volume and eliminates metastatic disease. Overall, we provide new insights into the isoform-specific roles of Prrx1a and Prrx1b in primary PDAC formation, dissemination, and metastatic colonization, allowing for novel therapeutic strategies targeting EMT plasticity.


Assuntos
Carcinoma Ductal Pancreático/fisiopatologia , Proteínas de Homeodomínio/metabolismo , Invasividade Neoplásica/fisiopatologia , Neoplasias Pancreáticas/fisiopatologia , Animais , Carcinogênese/genética , Carcinoma Ductal Pancreático/genética , Células Cultivadas , Regulação Neoplásica da Expressão Gênica , Fator de Crescimento de Hepatócito/genética , Proteínas de Homeodomínio/genética , Humanos , Camundongos , Metástase Neoplásica/genética , Neoplasias Pancreáticas/genética , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Células Tumorais Cultivadas
14.
Pharmgenomics Pers Med ; 8: 171-80, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26675332

RESUMO

Immortalization is an important step toward the malignant transformation of human cells and is critically dependent upon telomere maintenance. There are two known mechanisms to maintain human telomeres. The process of telomere maintenance is either mediated through activation of the enzyme telomerase or through an alternative mechanism of telomere lengthening called ALT. While 85% of all human tumors show reactivation of telomerase, the remaining 15% are able to maintain telomeres via ALT. The therapeutic potential of telomerase inhibitors is currently investigated in a variety of human cancers. Gastrointestinal tumors are highly dependent on telomerase as a mechanism of telomere maintenance, rendering telomeres as well as telomerase potential targets for cancer therapy. This article focuses on the molecular mechanisms of telomere biology and telomerase activation in gastrointestinal cancers and reviews strategies of telomerase inhibition and their potential therapeutic use in these tumor entities.

15.
Cancer Genet ; 206(11): 374-86, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24331919

RESUMO

Immortalization is an important step toward the malignant transformation of human cells and is critically dependent upon telomere maintenance. Two mechanisms are known to maintain human telomeres. The process of telomere maintenance is either mediated through activation of the enzyme telomerase or through an alternative mechanism of telomere lengthening called alternative lengthening of telomeres (ALT). Whereas 85% of all human tumors show reactivation of telomerase, the remaining 15% are able to maintain telomeres via ALT. Telomerase inhibitors are already investigated in clinical trials, although the regulation as well as potential coexistence and redundancy of both telomere maintenance mechanisms during distinct steps of carcinogenesis are poorly understood. Herein, we demonstrate that telomerase activity and ALT alternate in a cell cycle dependent fashion in human esophageal epithelial cells, and can coexist in a genetically defined model of oral-esophageal squamous carcinogenesis. Moreover, we show that immortalized premalignant cells as well as cancer cells are able to switch from telomerase activation to ALT upon inhibition of telomerase. This indicates that cancer cells treated with telomerase inhibitors can use alternative and adaptive ways to maintain their telomeres and thereby escape telomere-based therapeutic strategies.


Assuntos
Transformação Celular Neoplásica/genética , Neoplasias Esofágicas/enzimologia , Neoplasias Esofágicas/genética , Telomerase/metabolismo , Telômero/metabolismo , Carcinogênese/genética , Carcinogênese/metabolismo , Ciclo Celular/fisiologia , Transformação Celular Neoplásica/metabolismo , Ativação Enzimática , Células Epiteliais/citologia , Células Epiteliais/enzimologia , Neoplasias Esofágicas/metabolismo , Esôfago/citologia , Células HEK293 , Humanos , Telomerase/genética , Transfecção
16.
Nat Protoc ; 8(7): 1354-65, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23787893

RESUMO

The most common subtype of pancreatic cancer is pancreatic ductal adenocarcinoma (PDAC). PDAC resembles duct cells morphologically and, to some extent, at a molecular level. Recently, genetic-lineage labeling has become popular in the field of tumor biology in order to study cell-fate decisions or to trace cancer cells in the mouse. However, certain biological questions require a nongenetic labeling approach to purify a distinct cell population in the pancreas. Here we describe a protocol for isolating mouse pancreatic ductal epithelial cells and ductlike cells directly in vivo using ductal-specific Dolichos biflorus agglutinin (DBA) lectin labeling followed by magnetic bead separation. Isolated cells can be cultured (in two or three dimensions), manipulated by lentiviral transduction to modulate gene expression and directly used for molecular studies. This approach is fast (~4 h), affordable, results in cells with high viability, can be performed on the bench and is applicable to virtually all genetic and nongenetic disease models of the pancreas.


Assuntos
Técnicas de Cultura de Células/métodos , Expressão Gênica , Ductos Pancreáticos/citologia , Transdução Genética/métodos , Animais , Separação Celular/métodos , Células Cultivadas , Lentivirus/genética , Camundongos , Lectinas de Plantas/química , Reação em Cadeia da Polimerase Via Transcriptase Reversa
17.
Neoplasia ; 15(4): 359-72, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23555182

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) commonly contains a mutation in K-Ras(G12D) and is characterized by a desmoplastic reaction composed of deregulated, proliferating cells embedded in an abnormal extracellular matrix (ECM). Our previous observations imply that inhibiting the mitogen-activated protein kinase (MAPK)-extracellular signal-regulated kinase (ERK2) kinase signal pathway reverses a matrix metalloproteinase 1-specific invasive phenotype. Here, we investigated the specific genes downstream of MAPK-ERK2 responsible for the hyperproliferative abilities of human and murine primary ductal epithelial cells (PDCs) within an ECM. Compared with control, DNA synthesis and total cell proliferation was significantly increased in human PDCs harboring the PDAC common p53, Rb/p16(INK4a), and K-Ras (G12D) mutations. Both of these effects were readily reversed following small-molecule inhibition or lentiviral silencing of ERK2. Microarray analysis of PDCs in three-dimensional (3D) culture revealed a unique, MAPK-influenced gene signature downstream of K-Ras (G12D). Unbiased hierarchical analysis permitted filtration of tissue inhibitor of matrix metalloproteinase 1 (TIMP1). Pancreatic cells isolated from Pdx1-Cre; LSL-K-ras(G12D/+)-mutated mice exhibit increased TIMP1 RNA transcription compared to wild-type littermate controls. Analyses of both 3D, in vitro human K-Ras (G12D) PDCs and data mining of publicly annotated human pancreatic data sets correlatively indicate increased levels of TIMP1 RNA. While silencing TIMP1 did not significantly effect PDC proliferation, exogenous addition of human recombinant TIMP1 significantly increased proliferation but only in transformed K-Ras (G12D) PDCs in 3D. Overall, TIMP1 is an upregulated gene product and a proliferative inducer of K-Ras(G12D)-mutated PDCs through the ERK2 signaling pathway.


Assuntos
Proliferação de Células , Proteína Quinase 1 Ativada por Mitógeno/fisiologia , Proteínas Proto-Oncogênicas/genética , Inibidor Tecidual de Metaloproteinase-1/genética , Proteínas ras/genética , Animais , Butadienos/farmacologia , Carcinoma Ductal Pancreático , Linhagem Celular Tumoral , Células Epiteliais/metabolismo , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Sistema de Sinalização das MAP Quinases , Camundongos , Camundongos Transgênicos , Proteína Quinase 1 Ativada por Mitógeno/antagonistas & inibidores , Mutação de Sentido Incorreto , Nitrilas/farmacologia , Análise de Sequência com Séries de Oligonucleotídeos , Ductos Pancreáticos/patologia , Neoplasias Pancreáticas , Proteínas Proto-Oncogênicas p21(ras) , RNA Interferente Pequeno/genética , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Transcriptoma
18.
Genes Dev ; 27(3): 288-300, 2013 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-23355395

RESUMO

Pancreatic exocrine cell plasticity can be observed during development, pancreatitis with subsequent regeneration, and also transformation. For example, acinar-ductal metaplasia (ADM) occurs during acute pancreatitis and might be viewed as a prelude to pancreatic intraepithelial neoplasia (PanIN) and pancreatic ductal adenocarcinoma (PDAC) development. To elucidate regulatory processes that overlap ductal development, ADM, and the progression of normal cells to PanIN lesions, we undertook a systematic approach to identify the Prrx1 paired homeodomain Prrx1 transcriptional factor as a highly regulated gene in these processes. Prrx1 annotates a subset of pancreatic ductal epithelial cells in Prrx1creER(T2)-IRES-GFP mice. Furthermore, sorted Prrx1(+) cells have the capacity to self-renew and expand during chronic pancreatitis. The two isoforms, Prrx1a and Prrx1b, regulate migration and invasion, respectively, in pancreatic cancer cells. In addition, Prrx1b is enriched in circulating pancreatic cells (Pdx1cre;LSL-Kras(G12D/+);p53(fl/+);R26YFP). Intriguingly, the Prrx1b isoform, which is also induced in ADM, binds the Sox9 promoter and positively regulates Sox9 expression. This suggests a new hierarchical scheme whereby a Prrx1-Sox9 axis may influence the emergence of acinar-ductal metaplasia and regeneration. Furthermore, our data provide a possible explanation of why pancreatic cancer is skewed toward a ductal fate.


Assuntos
Proteínas de Homeodomínio/metabolismo , Pâncreas/patologia , Pâncreas/fisiologia , Neoplasias Pancreáticas/fisiopatologia , Regeneração/fisiologia , Animais , Linhagem Celular Tumoral , Células Cultivadas , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Proteínas de Homeodomínio/genética , Camundongos , Camundongos Endogâmicos C57BL , Pâncreas/citologia , Regiões Promotoras Genéticas/genética , Ligação Proteica , Isoformas de Proteínas/metabolismo , Fatores de Transcrição SOX9/genética
19.
Cancer Sci ; 102(2): 351-60, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21156006

RESUMO

Telomerase plays an important role during immortalization and malignant transformation as crucial steps in the development of human cancer. In a cellular model of oral-esophageal carcinogenesis, recapitulating the human disease, immortalization occurred independent of the activation of telomerase but through the recombination-based alternative lengthening of telomeres (ALT). In this stepwise model, additional overexpression of EGFR led to in vitro transformation and activation of telomerase with homogeneous telomere elongation in already immortalized oral squamous epithelial cells (OKF6-D1_dnp53). More interestingly, EGFR overexpression activated the PI3K/AKT pathway. This strongly suggested a role for telomerase in tumor progression in addition to just elongating telomeres and inferring an immortalized state. Therefore, we sought to identify the regulatory mechanisms involved in this activation of telomerase and in vitro transformation induced by EGFR. In the present study we demonstrate that telomerase expression and activity are induced through both direct phosphorylation of hTERT by phospho-AKT as well as PI3K-dependent transcriptional regulation involving Hif1-alpha as a key transcription factor. Furthermore, EGFR overexpression enhanced cell cycle progression and proliferation via phosphorylation and translocation of p21. Whereas immortalization was induced by ALT, in vitro transformation was associated with telomerase activation, supporting an additional role for telomerase in tumor progression besides elongating telomeres.


Assuntos
Transformação Celular Neoplásica/metabolismo , Receptores ErbB/biossíntese , Neoplasias Esofágicas/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Neoplasias Bucais/metabolismo , Telomerase/metabolismo , Western Blotting , Transformação Celular Neoplásica/genética , Células Cultivadas , Ativação Enzimática/fisiologia , Receptores ErbB/genética , Neoplasias Esofágicas/genética , Imunofluorescência , Expressão Gênica , Regulação Neoplásica da Expressão Gênica/fisiologia , Humanos , Imunoprecipitação , Hibridização in Situ Fluorescente , Neoplasias Bucais/genética , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/fisiologia , Transcrição Gênica
20.
Cell Cycle ; 5(6): 630-4, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16582608

RESUMO

The development of cancer in humans involves a complex accumulation of genetic and epigenetic events mainly in proto-oncogenes and tumor-suppressor genes. Different combinations of these alterations have been observed in a given human cancer and an ever-increasing number of these genes seem to be involved in the distinct steps of neoplastic transformation. Nevertheless, recent successes in experimental models of immortalization and malignant transformation of human cells indicate that the disruption of a limited number of cellular pathways is sufficient to induce a cancerous phenotype in a wide variety of normal cells. This review summarizes in vitro transformation models recapitulating human carcinogenesis, which suggest that a series of genetic and cellular principles may govern the formation of most, if not all, types of human cancer.


Assuntos
Transformação Celular Neoplásica/genética , Regulação Neoplásica da Expressão Gênica/genética , Genes Supressores de Tumor/fisiologia , Neoplasias/genética , Proto-Oncogenes/genética , Linhagem Celular Transformada , Transformação Celular Neoplásica/metabolismo , Humanos , Neoplasias/metabolismo , Neoplasias/fisiopatologia , Transdução de Sinais/genética
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