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1.
Gastrointest Endosc ; 98(2): 191-198, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36990125

RESUMO

BACKGROUND AND AIMS: The role of the newer EUS fine-needle biopsy needles in lymphadenopathies (LAs) is still under evaluation. We aimed to evaluate the diagnostic accuracy and adverse event rate of EUS-guided fine-needle biopsy sampling (EUS-FNB) in diagnosing LAs. METHODS: From June 2015 to June 2022, all patients referred to 4 institutions for EUS-FNB of mediastinal and abdominal LAs were enrolled. Twenty-two-gauge Franseen tip or 25-gauge fork-tip needles were used. The criterion standard for positive results was surgery or imaging and clinical evolution over a follow-up of at least 1 year. RESULTS: One hundred consecutive patients were enrolled, consisting of those with a new diagnosis of LA (40%), presence of LA with a previous history of neoplasia (51%), or suspected lymphoproliferative disease (9%). EUS-FNB was technically feasible in all LA patients with 2 to 3 passes (mean, 2.62 ± .93). The overall sensitivity, positive predictive value, specificity, negative predictive value, and accuracy for EUS-FNB were 96.20%, 100%, 100%, 87.50%, and 97.00%, respectively. Histologic analysis was feasible in 89% of cases. Cytologic evaluation was performed in 67% of specimens. A statistical difference between the accuracy of the 22-gauge or 25-gauge needle (P = .63) was not found. A subanalysis on lymphoproliferative disease revealed a sensitivity and accuracy of 89.29% and 90.0%, respectively. No adverse events were recorded. CONCLUSIONS: EUS-FNB with new end-cutting needles is a valuable and safe method to diagnose LAs. The high quality of histologic cores and the good amount of tissue allowed a complete immunohistochemical analysis of metastatic LAs and precise subtyping of the lymphomas. (Clinical trial registration number: NCT02855151.).


Assuntos
Linfadenopatia , Linfoma , Neoplasias , Neoplasias Pancreáticas , Humanos , Estudos Prospectivos , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico/efeitos adversos , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico/métodos , Linfadenopatia/diagnóstico , Linfoma/diagnóstico , Linfoma/patologia , Neoplasias Pancreáticas/patologia
3.
Endoscopy ; 55(2): 129-137, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36044915

RESUMO

BACKGROUND : The advantage of using the macroscopic on-site evaluation (MOSE) technique during endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB) performed with 22G Franseen needles has not been investigated. We aimed to compare EUS-FNB with MOSE vs. EUS-FNB performed with three needle passes. METHODS : This randomized trial involved 10 Italian referral centers. Consecutive patients referred for EUS-FNB of pancreatic or nonpancreatic solid lesions were included in the study and randomized to the two groups. MOSE was performed by gross visualization of the collected material by the endoscopists and considered adequate when a white/yellowish aggregate core longer than 10 mm was retrieved. The primary outcome was diagnostic accuracy. Secondary outcomes were specimen adequacy, number of needle passes, and safety. RESULTS : 370 patients with 234 pancreatic lesions (63.2 %) and 136 nonpancreatic lesions (36.8 %) were randomized (190 EUS-FNB with MOSE and 180 with standard EUS-FNB). No statistically significant differences were found between EUS-FNB with MOSE and conventional EUS-FNB in terms of diagnostic accuracy (90.0 % [95 %CI 84.8 %-93.9 %] vs. 87.8 % [95 %CI 82.1 %-92.2 %]; P = 0.49), sample adequacy (93.1 % [95 %CI 88.6 %-96.3 %] vs. 95.5 % [95 %CI 91.4 %-98 %]; P = 0.31), and rate of adverse events (2.6 % vs. 1.1 %; P = 0.28). The median number of passes was significantly lower in the EUS-FNB with MOSE group (1 vs. 3; P < 0.001). CONCLUSIONS : The accuracy of EUS-FNB with MOSE is noninferior to that of EUS-FNB with three needle passes. MOSE reliably assesses sample adequacy and reduces the number of needle passes required to obtain the diagnosis with a 22G Franseen needle.


Assuntos
Neoplasias Pancreáticas , Humanos , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico/métodos , Biópsia Guiada por Imagem , Pâncreas/diagnóstico por imagem , Pâncreas/patologia , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/patologia
4.
Endosc Int Open ; 9(6): E901-E906, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34079874

RESUMO

Background and study aims The standard method for obtaining samples during endoscopic ultrasonography (EUS) is fine-needle aspiration (FNA), the accuracy of which can be affected by the presence of a cytopathologist in endoscopy room (rapid on-site evaluation [ROSE]). With the introduction of fine-needle biopsy (FNB), macroscopic on-site evaluation (MOSE) of a acquired specimen has been proposed. Only a few studies have evaluated the role of MOSE and in all except one, a 19G needle was used. Our primary aim was to evaluate the diagnostic yield and accuracy of MOSE with different needle sizes and the secondary aim was to identify factors influencing the yield of MOSE. Patients and methods Data from patients who underwent EUS-FNB for solid lesions, with MOSE evaluation of the specimen, were collected in six endoscopic referral centers. Results A total of 378 patients (145 F and 233 M) were enrolled. Needles sizes used during the procedures were 20G (42 %), 22G (45 %), and 25G (13 %). The median number of needle passes was two (IQR 2-3). The overall diagnostic yield of MOSE was of 90 % (confidence interval [CI] 86 %-92 %). On multivariable logistic regression analysis, variables independently associated with the diagnostic yield of MOSE were a larger needle diameter (20G vs. 25G, OR 11.64, 95 %CI 3.5-38.71; 22G vs. 25G, OR 6.20, 95 %CI 2.41-15.90) and three of more needle passes (OR 3.39, 95 %CI 1.38-8.31). Conclusions MOSE showed high diagnostic yield and accuracy. Its yield was further increased if performed with a large size FNB needles and more than two passes.

5.
Dig Liver Dis ; 52(11): 1346-1350, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32601037

RESUMO

After the lockdown during the emergency phase of the Covid-19 pandemic, we have to deal with phase 2, a period of uncertain duration, with a controlled and progressive return to normalization, in which we need to reconcile our work and our movements with the presence of the virus on our territory. Digestive endoscopic activity is a high-risk transmission procedure for Covid-19. The measures put in place to protect healthcare personnel and patients are stressful and "time-consuming" and lead to a reduction in the number of endoscopic procedures that can be performed. In this scenario, the Oncological Institutes are forced to make a rigorous selection of patients to undergo endoscopic examinations and treatments, according to lists of exceptional priorities, in order to guarantee cancer patients and subjects at high risk of developing digestive tumors, a preferential diagnostic and therapeutic process, protected from contagion risks. For this purpose, cuts and postponing times of endoscopic performances are here proposed, which go beyond the guidelines of scientific societies and have little evidences in the literature. These changes should be applied limited to this exceptional period and in proportion to the capacity of each operating unit in order to meet the demands of the patients.


Assuntos
Institutos de Câncer/organização & administração , Endoscopia Gastrointestinal , Seleção de Pacientes , Betacoronavirus , COVID-19 , Controle de Doenças Transmissíveis/métodos , Infecções por Coronavirus/transmissão , Neoplasias Gastrointestinais/diagnóstico , Neoplasias Gastrointestinais/terapia , Humanos , Pandemias , Pneumonia Viral/transmissão , SARS-CoV-2
7.
Dig Liver Dis ; 52(1): 64-71, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31629705

RESUMO

BACKGROUND AND AIMS: Most of the evidence supporting endoscopic submucosal dissection (ESD) comes from Asia. European data are primarily reported by specialized referral centers and thus may not be representative of common European ESD practice. The aim of this study is to understand the current state of ESD practice across Italian endoscopy centers. METHODS: All Italian endoscopists who were known to perform ESD were invited to complete a structured questionnaire including: operator features and competencies, ESD training details and clinical outcomes over a 2-year period. RESULTS: Twenty-nine operators from 23 centers (69% response rate) completed the questionnaire: 18 (62%) were <50 years old; 7 (24%) were female; 16 (70%) were located in Northern Italy. Overall ESD volume was <40 cases in 9 (31%) operators, 40-80 in 8 (27.5%), 80-150 in 4 (13.8%) and >150 in 8 (27.5%). Colorectal ESD was predominant for operators with an experience >80 cases. En-bloc resection rates ranged from 77.2 to 97.2% depending on the anatomic location with an R0 resection rate range of 75.3-93.6%. ESD perforation rates in the colon and rectum were significantly lower when experience was >150 compared to 80-150 cases (p < 0.0001 and p = 0.006 for colon and rectum, respectively). CONCLUSION: ESD in Italy is performed by a significant number of operators. Overall, Italian endoscopists performing ESD have achieved a good competence level. However, there is much variability in training protocols, initial supervision of procedures, practice settings, case mix and procedural volume/year that are likely responsible for some of the suboptimal resectional outcomes and increased perforation risk, mainly in the colon. Standardized training programs, practice parameters and auditing of outcomes are required.


Assuntos
Competência Clínica , Colonoscopia/métodos , Dissecação/métodos , Mucosa Gástrica/cirurgia , Gastroscopia/métodos , Mucosa Intestinal/cirurgia , Idoso , Colo/cirurgia , Colonoscopia/efeitos adversos , Colonoscopia/educação , Dissecação/efeitos adversos , Dissecação/educação , Educação de Pós-Graduação em Medicina , Feminino , Humanos , Itália , Curva de Aprendizado , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/prevenção & controle , Reto/cirurgia , Estudos Retrospectivos , Inquéritos e Questionários , Resultado do Tratamento
8.
Dig Liver Dis ; 51(7): 978-984, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30718203

RESUMO

BACKGROUND: Prospective studies about endoscopic retrograde cholangio-pancreatography (ERCP) in a community setting are rare. AIM: To assess success and complication rates of routinely-performed ERCP in a regional setting, and the priority quality indicators for ERCP practice. METHODS: Prospective region wide observational study on consecutive patients undergoing ERCP during a 6-month period. A centralized online ERCP questionnaire was built and used for data storage. Primary quality indicators provided by the American Society of Gastrointestinal Endoscopy (ASGE) were considered. RESULTS: 38 endoscopists from 18 centers performed a total of 2388 ERCP. The most common indication for ERCP was choledocholitiasis (54.8%) followed by malignant jaundice (22.6%). Cannulation of the desired duct was obtained in 2293 cases (96%) and ERCP was successful in 2176 cases (91.1%). Success and ERCP difficulty were significantly related to the experience of the operator (p = 0.001 and p < 0.001, respectively). ERCP difficulty was also significantly related to volume centers (p < 0.01). The overall complication rate was 8.4%: post-ERCP pancreatitis (PEP) occurred in 4.1% of procedures, bleeding in 2.9%, infection in 0.8%, perforation in 0.4%. Mortality rate was 0.4%. All the ASGE priority quality indicators for ERCP were confirmed. CONCLUSIONS: The procedural questionnaire proved to be an important tool to assess and verify the quality of routinely-performed ERCP performance in a community setting.


Assuntos
Colangiopancreatografia Retrógrada Endoscópica/efeitos adversos , Colangiopancreatografia Retrógrada Endoscópica/estatística & dados numéricos , Hemorragia/epidemiologia , Pancreatite/epidemiologia , Indicadores de Qualidade em Assistência à Saúde , Cateterismo/estatística & dados numéricos , Coledocolitíase/diagnóstico por imagem , Coledocolitíase/cirurgia , Bases de Dados Factuais , Hemorragia/etiologia , Humanos , Itália/epidemiologia , Icterícia/diagnóstico por imagem , Modelos Logísticos , Pancreatite/etiologia , Estudos Prospectivos , Inquéritos e Questionários
9.
J Clin Gastroenterol ; 53(4): 269-276, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-29394176

RESUMO

GOALS: The aim of this study was to analyze the performance of Fuji Intelligent Color Enhancement (FICE) using the classification of Kudo in the differentiation of neoplastic and non-neoplastic raised lesions in ulcerative colitis (UC). BACKGROUND: The Kudo classification of mucosal pit patterns is an aid for the differential diagnosis of colorectal polyps in the general population, but no systematic studies are available for all forms of raised lesions in UC. STUDY: All raised, polypoid and nonpolypoid, lesions found during consecutive surveillance colonoscopies with FICE for long-standing UC were included. In the primary prospective analysis, the Kudo classification was used to predict the histology by FICE. In a post hoc analysis, further endoscopic markers were also explored. RESULTS: Two hundred and five lesions (mean size, 8 mm; range, 2 to 30 mm) from 59 patients (mean age, 56 y; range, 21 to 79 y) were analyzed. Twenty-three neoplastic (11%), 18 hyperplastic (9%), and 164 inflammatory (80%) lesions were found. Thirty-one lesions (15%), none of which were neoplastic, were unclassifiable according to Kudo. After logistic regression, a strong negative association resulted between endoscopic activity and neoplasia, whereas the presence of a fibrin cap was significantly associated with endoscopic activity. Using FICE, the sensitivity, specificity, and positive and negative likelihood ratios of the Kudo classification were 91%, 76%, 3.8, and 0.12, respectively. The corresponding values by adding the fibrin cap as a marker of inflammation were 91%, 93%, 13, and 0.10, respectively. CONCLUSIONS: FICE can help to predict the histology of raised lesions in UC. A new classification of pit patterns, based on inflammatory markers, should be developed in the setting of UC to improve the diagnostic performance.


Assuntos
Colite Ulcerativa/patologia , Pólipos do Colo/diagnóstico , Colonoscopia/métodos , Neoplasias Colorretais/diagnóstico , Adulto , Idoso , Pólipos do Colo/patologia , Cor , Diagnóstico Diferencial , Feminino , Humanos , Aumento da Imagem , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Sensibilidade e Especificidade , Adulto Jovem
10.
PLoS One ; 11(7): e0159373, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27441558

RESUMO

Little is known about the immunoediting process in precancerous lesions. We explored this aspect of benign colorectal adenomas with a descriptive analysis of the immune pathways and immune cells whose regulation is linked to the morphology and size of these lesions. Two series of polypoid and nonpolypoid colorectal adenomas were used in this study: 1) 84 samples (42 lesions, each with matched samples of normal mucosa) whose gene expression data were used to quantify the tumor morphology- and size-related dysregulation of immune pathways collected in the Molecular Signature Database, using Gene Set Enrichment Analysis; 2) 40 other lesions examined with immunohistochemistry to quantify the presence of immune cells in the stromal compartment. In the analysis of transcriptomic data, 429 immune pathways displayed significant differential regulation in neoplasms of different morphology and size. Most pathways were significantly upregulated or downregulated in polypoid lesions versus nonpolypoid lesions (regardless of size). Differential pathway regulation associated with lesion size was observed only in polypoid neoplasms. These findings were mirrored by tissue immunostaining with CD4, CD8, FOXP3, MHC-I, CD68, and CD163 antibodies: stromal immune cell counts (mainly T lymphocytes and macrophages) were significantly higher in polypoid lesions. Certain markers displayed significant size-related differences regardless of lesion morphology. Multivariate analysis of variance showed that the marker panel clearly discriminated between precancerous lesions of different morphologies and sizes. Statistical analysis of immunostained cell counts fully support the results of the transcriptomic data analysis: the density of infiltration of most immune cells in the stroma of polypoid precancerous lesions was significantly higher than that observed in nonpolypoid lesions. Large neoplasms also have more immune cells in their stroma than small lesions. Immunoediting in precancerous colorectal tumors may vary with lesion morphology and stage of development, and this variability could influence a given lesion's trajectory to cancer.


Assuntos
Pólipos Adenomatosos/imunologia , Neoplasias Colorretais/imunologia , Lesões Pré-Cancerosas/imunologia , Pólipos Adenomatosos/genética , Pólipos Adenomatosos/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Contagem de Células , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/patologia , Células Estromais/patologia
12.
Mol Cell Proteomics ; 13(5): 1198-218, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24567419

RESUMO

Colorectal adenomas are cancer precursor lesions of the large bowel. A multitude of genomic and epigenomic changes have been documented in these preinvasive lesions, but their impact on the protein effectors of biological function has not been comprehensively explored. Using shotgun quantitative MS, we exhaustively investigated the proteome of 30 colorectal adenomas and paired samples of normal mucosa. Total protein extracts were prepared from these tissues (prospectively collected during colonoscopy) and from normal (HCEC) and cancerous (SW480, SW620, Caco2, HT29, CX1) colon epithelial cell lines. Peptides were labeled with isobaric tags (iTRAQ 8-plex), separated via OFFGEL electrophoresis, and analyzed by means of LC-MS/MS. Nonredundant protein families (4325 in tissues, 2017 in cell lines) were identified and quantified. Principal component analysis of the results clearly distinguished adenomas from normal mucosal samples and cancer cell lines from HCEC cells. Two hundred and twelve proteins displayed significant adenoma-related expression changes (q-value < 0.02, mean fold change versus normal mucosa ±1.4), which correlated (r = 0.74) with similar changes previously identified by our group at the transcriptome level. Fifty-one (∼25%) proteins displayed directionally similar expression changes in colorectal cancer cells (versus HCEC cells) and were therefore attributed to the epithelial component of adenomas. Although benign, adenomas already exhibited cancer-associated proteomic changes: 69 (91%) of the 76 protein up-regulations identified in these lesions have already been reported in cancers. One of the most striking changes involved sorbitol dehydrogenase, a key enzyme in the polyol pathway. Validation studies revealed dramatically increased sorbitol dehydrogenase concentrations and activity in adenomas and cancer cell lines, along with important changes in the expression of other enzymes in the same (AKR1B1) and related (KHK) pathways. Dysregulated polyol metabolism might represent a novel facet of metabolome remodeling associated with tumorigenesis.


Assuntos
Adenoma/patologia , Aldeído Redutase/metabolismo , Neoplasias Colorretais/patologia , Frutoquinases/metabolismo , Mucosa Gástrica/metabolismo , L-Iditol 2-Desidrogenase/metabolismo , Adenoma/metabolismo , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/metabolismo , Células CACO-2 , Linhagem Celular Tumoral , Cromatografia Líquida , Neoplasias Colorretais/metabolismo , Regulação Neoplásica da Expressão Gênica , Células HT29 , Humanos , L-Iditol 2-Desidrogenase/genética , Masculino , Espectrometria de Massas , Pessoa de Meia-Idade , Proteômica/métodos , Reprodutibilidade dos Testes
13.
BMC Cancer ; 14: 46, 2014 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-24472434

RESUMO

BACKGROUND: Biological processes are controlled by transcription networks. Expression changes of transcription factor (TF) genes in precancerous lesions are therefore crucial events in tumorigenesis. Our aim was to obtain a comprehensive picture of these changes in colorectal adenomas. METHODS: Using a 3-pronged selection procedure, we analyzed transcriptomic data on 34 human tissue samples (17 adenomas and paired samples of normal mucosa, all collected with ethics committee approval and written, informed patient consent) to identify TFs with highly significant tumor-associated gene expression changes whose potential roles in colorectal tumorigenesis have been under-researched. Microarray data were subjected to stringent statistical analysis of TF expression in tumor vs. normal tissues, MetaCore-mediated identification of TF networks displaying enrichment for genes that were differentially expressed in tumors, and a novel quantitative analysis of the publications examining the TF genes' roles in colorectal tumorigenesis. RESULTS: The 261 TF genes identified with this procedure included DACH1, which plays essential roles in the proper proliferation and differentiation of retinal and leg precursor cell populations in Drosophila melanogaster. Its possible roles in colorectal tumorigenesis are completely unknown, but it was found to be markedly overexpressed (mRNA and protein) in all colorectal adenomas and in most colorectal carcinomas. However, DACH1 expression was absent in some carcinomas, most of which were DNA mismatch-repair deficient. When networks were built using the set of TF genes identified by all three selection procedures, as well as the entire set of transcriptomic changes in adenomas, five hub genes (TGFB1, BIRC5, MYB, NR3C1, and TERT) where identified as putatively crucial components of the adenomatous transformation process. CONCLUSION: The transcription-regulating network of colorectal adenomas (compared with that of normal colorectal mucosa) is characterized by significantly altered expression of over 250 TF genes, many of which have never been investigated in relation to colorectal tumorigenesis.


Assuntos
Adenoma/genética , Biomarcadores Tumorais/genética , Neoplasias Colorretais/genética , Perfilação da Expressão Gênica , Fatores de Transcrição/genética , Adenoma/metabolismo , Adenoma/patologia , Biomarcadores Tumorais/metabolismo , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Análise por Conglomerados , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Proteínas do Olho/genética , Proteínas do Olho/metabolismo , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Genes myb , Humanos , Imuno-Histoquímica , Proteínas Inibidoras de Apoptose/genética , Proteínas Inibidoras de Apoptose/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , RNA Mensageiro/metabolismo , Receptores de Glucocorticoides/genética , Receptores de Glucocorticoides/metabolismo , Survivina , Telomerase/genética , Telomerase/metabolismo , Fatores de Transcrição/metabolismo , Transcrição Gênica , Fator de Crescimento Transformador beta1/genética , Fator de Crescimento Transformador beta1/metabolismo
14.
Dig Liver Dis ; 45(3): 207-10, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23107488

RESUMO

BACKGROUND AND AIMS: Advances in colonoscopy, such as the Pentax i-Scan electronic technique, have the potential to improve the early detection of colorectal cancer. The aim of this multicentre study was to assess the interobserver agreement in the visualization of the surface and margins of colorectal polyps and in distinguishing neoplastic from non-neoplastic polyps. PATIENTS AND METHODS: Eight expert endoscopists examined 400 mixed previously recorded images of polyps taken with different Pentax i-Scan settings in order to give an evaluation of the surface of the polyp and regular colonic mucosa, the pit-pattern and the nature of the lesion. RESULTS: A total of 400 mixed images of polyps with a diameter >5mm and <10mm were stored for analysis. Overall, there was a Kf agreement of 0.370 (p<0.001) and 0.306 (p<0.001) regarding pit-pattern and margins, respectively. The Kf agreement for the difference between neoplastic and non-neoplastic lesions was of 0.446 (p<0.001). CONCLUSIONS: We observed good interobserver agreement in the evaluation of neoplastic and non-neoplastic lesions and poor agreement in the evaluation of pit-pattern and margins. Adequate training is required in order to interpret images acquired with the i-Scan technique.


Assuntos
Pólipos do Colo/patologia , Colonoscopia/estatística & dados numéricos , Neoplasias Colorretais/patologia , Mucosa Intestinal/patologia , Idoso , Colonoscopia/métodos , Feminino , Humanos , Aumento da Imagem , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador
15.
BMC Cancer ; 12: 608, 2012 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-23253212

RESUMO

BACKGROUND: The malignant transformation of precancerous colorectal lesions involves progressive alterations at both the molecular and morphologic levels, the latter consisting of increases in size and in the degree of cellular atypia. Analyzing preinvasive tumors of different sizes can therefore shed light on the sequence of these alterations. METHODS: We used a molecular pathway-based approach to analyze transcriptomic profiles of 59 colorectal tumors representing early and late preinvasive stages and the invasive stage of tumorigenesis. Random set analysis was used to identify biological pathways enriched for genes differentially regulated in tumors (compared with 59 samples of normal mucosa). RESULTS: Of the 880 canonical pathways we investigated, 112 displayed significant tumor-related upregulation or downregulation at one or more stages of tumorigenesis. This allowed us to distinguish between pathways whose dysregulation is probably necessary throughout tumorigenesis and those whose involvement specifically drives progression from one stage to the next. We were also able to pinpoint specific changes within each gene set that seem to play key roles at each transition. The early preinvasive stage was characterized by cell-cycle checkpoint activation triggered by DNA replication stress and dramatic downregulation of basic transmembrane signaling processes that maintain epithelial/stromal homeostasis in the normal mucosa. In late preinvasive lesions, there was also downregulation of signal transduction pathways (e.g., those mediated by G proteins and nuclear hormone receptors) involved in cell differentiation and upregulation of pathways governing nuclear envelope dynamics and the G2>M transition in the cell cycle. The main features of the invasive stage were activation of the G1>S transition in the cell cycle, upregulated expression of tumor-promoting microenvironmental factors, and profound dysregulation of metabolic pathways (e.g., increased aerobic glycolysis, downregulation of pathways that metabolize drugs and xenobiotics). CONCLUSIONS: Our analysis revealed specific pathways whose dysregulation might play a role in each transition of the transformation process. This is the first study in which such an approach has been used to gain further insights into colorectal tumorigenesis. Therefore, these data provide a launchpad for further exploration of the molecular characterization of colorectal tumorigenesis using systems biology approaches.


Assuntos
Transformação Celular Neoplásica/genética , Neoplasias do Colo/genética , Perfilação da Expressão Gênica , Transdução de Sinais/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias do Colo/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transcriptoma
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