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1.
Oncologist ; 27(6): 430-e433, 2022 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-35675633

RESUMO

BACKGROUND: Photochemical internalization (PCI) is a novel technology for light-induced enhancement of the local therapeutic effect of cancer drugs, utilizing a specially designed photosensitizing molecule (fimaporfin). The photosensitizing molecules are trapped in endosomes along with macromolecules or drugs. Photoactivation of fimaporfin disrupts the endosomal membranes so that drug molecules are released from endosomes inside cells and can reach their therapeutic target in the cell cytosol or nucleus. Compared with photodynamic therapy, the main cytotoxic effect with PCI is disruption of the endosomal membrane resulting in delivery of chemotherapy drug, and not to the photochemical reactions per se. In this study we investigated the effect of PCI with gemcitabine in patients with inoperable perihilar cholangiocarcinoma (CCA). METHODS: The in vitro cytotoxic effect of PCI with gemcitabine was studied on two CCA-derived cell lines. In a fimaporfin dose-escalation phase I clinical study, we administered PCI with gemcitabine in patients with perihilar CCA (n = 16) to establish a safe and tolerable fimaporfin dose and to get early signals of efficacy. The patients enrolled in the study had tumors in which the whole length of the tumor could be illuminated from the inside of the bile duct, using an optical fiber inserted via an endoscope (Fig. 1). Fimaporfin was administered intravenously at day 0; gemcitabine (i.v.) and intraluminal biliary endoscopic laser light application on day 4; followed by standard gemcitabine/cisplatin chemotherapy. RESULTS: Preclinical experiments showed that PCI enhanced the effect of gemcitabine. In patients with CCA, PCI with gemcitabine was well tolerated with no dose-limiting toxicities, and no unexpected safety signals. Disease control was achieved in 10 of 11 evaluable patients, with a clearly superior effect in the two highest dose groups. The objective response rate (ORR) was 42%, including two complete responses, while ORR at the highest dose was 60%. Progression-free survival at 6 months was 75%, and median overall survival (mOS) was 15.4 months, with 22.8 months at the highest fimaporfin dose. CONCLUSION: Photochemical internalization with gemcitabine was found to be safe and resulted in encouraging response and survival rates in patients with unresectable perihilar CCA.


Assuntos
Colangiocarcinoma , Desoxicitidina , Fotoquimioterapia , Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias dos Ductos Biliares/tratamento farmacológico , Ductos Biliares Intra-Hepáticos , Colangiocarcinoma/tratamento farmacológico , Colangiocarcinoma/patologia , Desoxicitidina/efeitos adversos , Desoxicitidina/análogos & derivados , Humanos , Fotoquimioterapia/efeitos adversos , Fotoquimioterapia/métodos , Gencitabina
2.
Endosc Int Open ; 8(12): E1878-E1883, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33269324

RESUMO

Photochemical internalization (PCI) is a technology to induce a localized, intracellular enhancement of therapeutics that are processed through endosomal pathways, including gemcitabine in malignant cells. In addition to a direct phototoxic and tumoricidal effect, PCI specifically disrupts endosomal membranes and, thereby, the compartmentalization of certain cytotoxic compounds to enhance a drug's intended intracellular target reach within the tissue treated. Non-resectable extrahepatic cholangiocarcinoma (eCCA) is a common primary tumor and gemcitabine/cisplatin chemotherapy is widely considered standard of care for it. PCI is well suited as an endoscopic intervention, and clinical observations in three subjects participating in a phase I/IIa dose escalation safety trial are described. The trial included patients with perihilar, non-resectable CCA suitable for standard-of-care chemotherapy. Per protocol, a single endoscopic PCI procedure with gemcitabine was conducted at the initiation of standard gemcitabine/cisplatin therapy. Sixteen patients enrolled in the initial dose escalation phase of the trial, which later was extended to explore the safety of a second PCI procedure during chemotherapy. While limited to a case series, the various clinical observations described here serve to illustrate the effects of localized, perihilar tumor targeting in appropriate patients by any safe methodology, including PCI. As previously indicated by clinical data using other localized treatment modalities, adding a directed, tumor-targeting treatment to systemic therapy to ameliorate the progressively expanding extrahepatic tumor burden can have important effects on the overall outcome of systemic treatment in many patients who have incurable eCCA.

3.
Front Immunol ; 11: 576756, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33488576

RESUMO

Background and Aims: Photochemical internalization (PCI) is a technology for inducing release of endocytosed antigens into the cell cytosol via a light-induced process. Preclinical experiments have shown that PCI improves MHC class I antigen presentation, resulting in strongly enhanced CD8+ T-cell responses to polypeptide antigens. In PCI vaccination a mixture of the photosensitizing compound fimaporfin, vaccine antigens, and an adjuvant is administered intradermally followed by illumination of the vaccination site. This work describes an open label, phase I study in healthy volunteers, to assess the safety, tolerability, and immune response to PCI vaccination in combination with the adjuvant poly-ICLC (Hiltonol) (ClinicalTrials.gov Identifier: NCT02947854). Methods: The primary objective of the study was to assess the safety and local tolerance of PCI mediated vaccination, and to identify a safe fimaporfin dose for later clinical studies. A secondary objective was to analyze the immunological responses to the vaccination. Each subject received 3 doses of HPV16 E7 peptide antigens and two doses of Keyhole Limpet Hemocyanin (KLH) protein. A control group received Hiltonol and vaccine antigens only, whereas the PCI groups in addition received fimaporfin + light. Local and systemic adverse effects were assessed by standard criteria, and cellular and humoral immune responses were analyzed by ELISpot, flow cytometry, and ELISA assays. Results: 96 healthy volunteers were vaccinated with fimaporfin doses of 0.75-50 µg. Doses below 17.5 µg were safe and tolerable, higher doses exhibited local tolerability issues in some study subjects, mainly erythema, and pain during illumination. There were few, and only mild and expected systemic adverse events. The employment of PCI increased the number of subjects exhibiting a T-cell response to the HPV peptide vaccine about 10-fold over what was achieved with the antigen/Hiltonol combination without PCI. Moreover, the use of PCI seemed to result in a more consistent and multifunctional CD8+ T-cell response. An enhancement of the humoral immune response to KLH vaccination was also observed. Conclusions: Using PCI in combination with Hiltonol for intradermal vaccination is safe at fimaporfin doses below 17.5 µg, and gives encouraging immune responses to peptide and protein based vaccination.


Assuntos
Papillomavirus Humano 16/fisiologia , Proteínas E7 de Papillomavirus/imunologia , Infecções por Papillomavirus/imunologia , Vacinas contra Papillomavirus/imunologia , Peptídeos/imunologia , Fármacos Fotossensibilizantes/imunologia , Linfócitos T/imunologia , Vacinação/métodos , Adulto , Células Cultivadas , Feminino , Voluntários Saudáveis , Humanos , Imunidade Celular , Iluminação , Masculino , Pessoa de Meia-Idade , Processos Fotoquímicos , Vacinas de Subunidades Antigênicas , Adulto Jovem
4.
Rheumatology (Oxford) ; 55(8): 1499-506, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27143789

RESUMO

OBJECTIVE: Anakinra is approved for the treatment of RA and cryopyrin-associated periodic syndromes (CAPS). While the anakinra safety profile is well established in RA, the long-term safety profile in severe CAPS is less well documented and will therefore be discussed in this report. METHODS: A prospective, open-label, single centre, clinical cohort study was conducted at the National Institutes of Health in the USA, from 2003 to 2010, investigating the efficacy and safety of anakinra treatment for up to 5 years in 43 patients with CAPS. Safety was evaluated using adverse event (AE) reports, laboratory assessments, vital signs and diary reports. RESULTS: In total, 1233 AEs were reported during the study, with a yearly rate of 7.7 AEs per patient. The event rate decreased over time, and dose escalation during the study did not affect AE frequency. Anakinra had similar safety profiles in adults and children. The most frequently reported AEs were typical CAPS disease symptoms such as headache and arthralgia. Injection site reactions occurred mainly during the first month of anakinra treatment. In total, 14 patients experienced 24 serious AEs (SAEs), all of which resolved during the study period. The most common types of SAEs were infections such as pneumonia and gastroenteritis. There were no permanent discontinuations of treatment due to AEs. CONCLUSION: In this study anakinra treatment of patients with severe CAPS for up to 5 years was safe and well tolerated both in paediatric and adult patients, with most AEs emerging during the first months after treatment initiation. TRIAL REGISTRATION: ClincialTrials.gov, clinicaltrials.gov, NCT00069329.


Assuntos
Antirreumáticos/efeitos adversos , Síndromes Periódicas Associadas à Criopirina/tratamento farmacológico , Proteína Antagonista do Receptor de Interleucina 1/efeitos adversos , Adolescente , Adulto , Antirreumáticos/administração & dosagem , Artralgia/induzido quimicamente , Criança , Pré-Escolar , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Gastroenterite/induzido quimicamente , Transtornos da Cefaleia/induzido quimicamente , Humanos , Injeções Subcutâneas , Proteína Antagonista do Receptor de Interleucina 1/administração & dosagem , Masculino , Pessoa de Meia-Idade , Segurança do Paciente , Pneumonia/induzido quimicamente , Estudos Prospectivos , Resultado do Tratamento , Adulto Jovem
5.
Int J Oncol ; 39(2): 311-8, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21573504

RESUMO

Colorectal cancer (CRC) is one of the most common and deadly forms of cancer. Despite improved treatment modalities, post-operative recurrence and metastasis remain the major problems for extending patient survival after surgery. This highlights the need to search for biomarkers for prognostication and treatment stratification of colorectal cancer patients. In this study, we applied the SYBR-green quantitative PCR-based array approach to screen for differentially expressed miRNAs between patients with short (<50 months, range 10-33 months) and long survival (≥ 50 months, range 50-152 months). The selected candidate prognostic miRNAs were validated in a cohort of 50 CRC patients by TaqMan quantitative PCR. We found that high expression of miR-185 and low expression of miR-133b were correlated with poor survival (p=0.001 and 0.028, respectively) and metastasis (p=0.007 and 0.036, respectively) in colorectal cancer. Our findings suggest the potential prognostic values of these miRNAs for predicting clinical outcome after surgery.


Assuntos
Neoplasias Colorretais/fisiopatologia , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise por Conglomerados , Neoplasias Colorretais/mortalidade , Regulação para Baixo , Feminino , Perfilação da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Prognóstico
6.
Oncol Rep ; 25(1): 253-8, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21109984

RESUMO

The prognostic value of gene abnormalities in colorectal cancer is unclear, varies between investigators, and may be unreliable due to tumor heterogeneity. We analyzed tumors completely divided into biopsies to characterize the overall distribution of LOH at 5q, 17p, 18q, K-ras mutations, and methylation of the p16 and MGMT genes. Seventeen tumors (stage II-III) were completely divided into biopsy cubes from which DNA was sequentially analyzed. The results from fragment analysis for LOH at 5q, 17p, 18q, TGGE of the K-ras, and MSP for p16 and MGMT genes were used to characterize the occurrence of these aberrations. LOH at 18q, 17p, and LOH 5q were present in 17/17, 15/17, and 15/16 tumors, respectively. p16 and MGMT were methylated in 16/17 and 14/17, respectively. The frequency of these aberrations varied largely between tumors. K-ras-mutations, present in 8/17 tumors, were much more consistently distributed in mutated tumor. Methylation of p16 and MGMT and LOH at 18q, 17p, and 5q are present within the tumor mass in a large majority of CRC tumors and are of no or little prognostic value. K-ras mutations appear more homogeneously distributed. This has clinical relevance for biopsing to predict anti-EGFR response.


Assuntos
Neoplasias Colorretais/genética , Análise Mutacional de DNA/métodos , Genes ras/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Neoplasias Colorretais/patologia , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Feminino , Genes p16 , Humanos , Perda de Heterozigosidade , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Proteínas Supressoras de Tumor/genética
7.
Clin Cancer Res ; 13(12): 3748-52, 2007 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-17575241

RESUMO

PURPOSE: Recently a common variant of the TGFBR1 gene, TGFBR1*6A, has been proposed to act as a low-penetrance tumor susceptibility allele for colorectal cancer, but data from published studies with individually low statistical power are conflicting. To further evaluate the relationship between TGFBR1*6A and colorectal cancer risk, we have conducted a large case-control study and a meta-analysis of previously published studies. EXPERIMENTAL DESIGN: A total of 1,042 colorectal cancer cases and 856 population controls were genotyped for the TGFBR1*6A polymorphism. Previously published case-control studies of the relationship between TGFBR1*6A and colorectal cancer were identified, and a meta-analysis was conducted. RESULTS: We found no evidence that homozygosity, heterozygosity or carrier status for the TGFBR1*6A allele confers an increased risk of colorectal cancer; respective odds ratios (OR) were 1.05 [95% confidence interval (95% CI), 0.83-1.32], 0.82 (95% CI, 0.34-1.99), and 0.92 (95% CI, 0.74-1.15), respectively. A meta-analysis of our case-control study and seven other studies that provided data on 2,627 colorectal cancer cases and 3,387 controls also yielded no evidence that possession of the TGFBR1*6A allele is associated with an elevated risk of colorectal cancer; pooled estimate of the OR were 1.20 (95% CI, 0.64-2.24) for homozygosity, 1.11 (95% CI, 0.96-1.29) for heterozygosity, and 1.13 (95% CI, 0.98-1.30) for carriers of TGFBR1*6A. CONCLUSION: Current data provide limited support for the hypothesis that sequence variation in TGFBR1 defined by the TGFBR1*6A allele confers an elevated risk of colorectal cancer.


Assuntos
Neoplasias Colorretais/genética , Predisposição Genética para Doença , Polimorfismo Genético , Proteínas Serina-Treonina Quinases/genética , Receptores de Fatores de Crescimento Transformadores beta/genética , Estudos de Casos e Controles , Genótipo , Humanos , Reação em Cadeia da Polimerase , Receptor do Fator de Crescimento Transformador beta Tipo I , Fatores de Risco
9.
Anticancer Res ; 26(6C): 4885-8, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17214356

RESUMO

BACKGROUND: The cell cycle checkpoint kinase 2 (CHEK2) 1100delC variant has recently been identified at high frequency in families with both breast and colorectal cancer, suggesting the possible role of this variant in colorectal cancer predisposition. PATIENTS AND METHODS: To evaluate the role of CHEK2 ll00delC among Swedish colorectal cancer patients, the variant frequency was determined in 174 selected familial cases, 644 unselected cases and 760 controls, as well as in l8 families used in the genome-wide linkage analysis, where weak linkage was seen for the region harboring the CHEK2 gene. RESULTS: CHEK2 l100delC was found in 1.15% of familial and in 0.93% of unselected cases, compared to 0.66% of controls, showing no significant difference between groups. One out of 45 familial cases with a family history of breast cancer was shown to be a carrier. The variant was not identified in the 18 families included in the linkage analysis. CONCLUSION: The CHEK2 1100delC was not significantly increased in Swedish colorectal cancer patients, however, in order to determine the role of the variant in colorectal cancer families with the history of breast cancer a larger sample size is needed.


Assuntos
Neoplasias Colorretais/enzimologia , Neoplasias Colorretais/genética , Proteínas Serina-Treonina Quinases/genética , Estudos de Casos e Controles , Quinase do Ponto de Checagem 2 , Cromossomos Humanos Par 22 , Mutação em Linhagem Germinativa , Humanos , Suécia
10.
Anticancer Res ; 25(1B): 657-61, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15816642

RESUMO

Free DNA in the circulation is increased five-to ten-fold in patients with solid tumours compared to healthy controls. A range of tumor-specific mutated DNA has been shown to be readily extractable and possible to analyse from plasma and serum in these patients. K-ras oncogene mutations are an early event in a subset of colorectal tumors and have been found in 30-60% of patients with colorectal carcinoma (CRC). The presence of tumor-derived k-ras gene mutations in the circulation has previously been described before surgery. The aim of this study was to characterize the presence of mutant k-ras in plasma in the short-term postoperative period after radical surgery of CRC patients, and further to characterize this in relation to relapse of the disease. Tumors and corresponding plasma pre- and postoperatively on day three after surgery were collected from 25 patients with CRC (Dukes' stage A-D). Biopsies for DNA extraction from the tumors were collected from the most invasive parts microscopically. After PCR amplification of the k-ras gene (codon 12 and 13), the presence of mutations was analysed by TGGE (temperature gradient gel electrophoresis). Twenty four/25 patients underwent putatively curative resections. Sixteen of the 25 patients (64%) expressed k-ras mutations in their tumor. Of these, 9 patients (56%) also had detectable k-ras mutations in preoperative plasma samples. On day three postoperatively, 8 of these patients persistently were found to have mutant k-ras in the plasma. This was not correlated with tumor stage. None of the 9 tumor mutation-negative cases expressed mutated k-ras in their plasma pre- or postoperatively. The results indicate that plasma mutant k-ras can be detected pre- and early postoperatively in all stages of colorectal neoplasia. No correlation between short-term postoperative persistence of mutant plasma-DNA and disease recurrence at follow-up was found. However, the use of k-ras as a marker during postoperative follow-up and as a possible tool for early detection of recurrent disease must be further characterized.


Assuntos
Neoplasias Colorretais/sangue , Neoplasias Colorretais/genética , Neoplasias Colorretais/cirurgia , Genes ras , Mutação , Idoso , Idoso de 80 Anos ou mais , Biópsia , Carcinoma/sangue , Carcinoma/genética , Carcinoma/cirurgia , DNA/sangue , DNA/metabolismo , DNA de Neoplasias , Eletroforese , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Fatores de Tempo
11.
Arterioscler Thromb Vasc Biol ; 24(2): 349-56, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14656733

RESUMO

OBJECTIVE: Growth hormone (GH) induces hepatic low-density lipoprotein (LDL) receptors and lowers plasma cholesterol. We characterized the influence of GH treatment on plasma LDL clearance in normal humans and investigated the relative role of LDL receptor (LDLR) activity and stimulation of bile acid synthesis in subjects with different LDLR expression. METHODS AND RESULTS: Plasma clearance of autologous 125I-LDL was measured before and during 3 weeks of treatment with GH (0.1 IU/kg per day) in 9 healthy young males. Plasma LDL cholesterol was reduced by 13% and the fractional catabolic rate of LDL increased by 27%. More marked changes were seen in a patient with hypopituitarism substituted with GH (0.07 IU/kg per day) for 3 months. In a second study, GH dose-dependently reduced LDL cholesterol and increased Lp(a) levels in 3 groups of males: younger and elderly healthy subjects and heterozygous familial hypercholesterolemia (FH). No effect on bile acid synthesis measured by the plasma marker 7alpha-hydroxy-4-cholesten-3-one was observed. In an LDLR-deficient FH homozygote, LDL cholesterol was not affected by GH. CONCLUSIONS: GH treatment reduces plasma LDL cholesterol by inducing LDL clearance. In humans, LDLR expression is a prerequisite for this effect, whereas it is not related to stimulation of bile acid synthesis.


Assuntos
Ácidos e Sais Biliares/biossíntese , Hormônio do Crescimento Humano/farmacologia , Lipoproteínas LDL/metabolismo , Adulto , Atorvastatina , Criança , LDL-Colesterol/sangue , LDL-Colesterol/metabolismo , LDL-Colesterol/urina , Colestipol/uso terapêutico , Relação Dose-Resposta a Droga , Esquema de Medicação , Quimioterapia Combinada , Feminino , Ácidos Heptanoicos/uso terapêutico , Heterozigoto , Hormônio do Crescimento Humano/administração & dosagem , Hormônio do Crescimento Humano/uso terapêutico , Humanos , Hiperlipoproteinemia Tipo II/sangue , Hiperlipoproteinemia Tipo II/tratamento farmacológico , Hiperlipoproteinemia Tipo II/metabolismo , Hiperlipoproteinemia Tipo II/urina , Hipopituitarismo/sangue , Hipopituitarismo/metabolismo , Hipopituitarismo/urina , Lipoproteínas LDL/sangue , Lipoproteínas LDL/urina , Masculino , Pessoa de Meia-Idade , Pirróis/uso terapêutico
12.
J Clin Endocrinol Metab ; 87(9): 4307-13, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12213890

RESUMO

To characterize the coordinate regulation of cholesterol metabolism in human liver, we simultaneously quantified mRNA levels of cholesterol 7alpha-hydroxylase (CYP7A1), 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGR), and low- density lipoprotein receptors (LDLRs) in liver biopsies from 76 patients undergoing cholecystectomy. The three transcript levels were not different between untreated gallstone and gallstone-free patients and not significantly altered by 10-d exclusion of dietary cholesterol. Treatment with chenodeoxycholic acid suppressed CYP7A1 and to a lesser extent HMGR mRNA levels. Cholestyramine treatment increased CYP7A1, but also HMGR and LDLR mRNA, and statins only increased HMGR mRNA. Resin + statin treatment increased all mRNA species. In untreated patients, the mRNA levels of HMGR and LDLR were more strongly correlated (r = +0.60) than those of CYP7A1 and HMGR (r = +0.49) or CYP7A1 and LDLR (r = +0.21). In the treated patients, in whom bile acid synthesis was suppressed or stimulated, mRNA levels of CYP7A1 and HMGR (r = +0.84) as well as CYP7A1 and LDLR (r = +0.62) were more strongly correlated than those of HMGR and LDLR (r = +0.59). The coordinate control of HMGR and LDLR mRNA levels reflects their common regulation by shared transcriptional activation. In contrast, following changes in bile acid flux through the liver, CYP7A1 gene expression becomes a strong modulator of hepatic cholesterol metabolism.


Assuntos
Colesterol 7-alfa-Hidroxilase/genética , Regulação da Expressão Gênica , Hidroximetilglutaril-CoA Redutases/genética , Fígado/metabolismo , RNA Mensageiro/genética , Receptores de LDL/genética , Adulto , Idoso , Colecistectomia , Colelitíase/genética , Resina de Colestiramina/metabolismo , Feminino , Regulação Enzimológica da Expressão Gênica , Humanos , Fígado/enzimologia , Masculino , Pessoa de Meia-Idade , Análise de Regressão
13.
Int J Colorectal Dis ; 17(2): 92-7, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12014427

RESUMO

BACKGROUND: In a small subgroup of patients with ulcerative colitis (UC) undergoing proctocolectomy and restorative ileal pouch-anal anastomosis (IPAA), a colonic-like pouch mucosa with severe and persistent villous atrophy (type C pattern) develops. Neoplastic transformation of the mucosa in the neorectum may occur in these patients. We hypothesized that genetic alterations associated with colorectal carcinoma (CRC) could be an early finding in this transformational process and thus potentially useful as clinical monitors in carcinoma risk assessment. METHODS: In six patients with long-standing severe pouchitis and a type C-pattern mucosa, biopsies were obtained from five different locations of the pouches. DNA was PCR-amplified and analyzed by automated fragment analysis for loss of heterozygosity (LOH) at chromosome 5q14-22, 17p12-13, and 18q12-22. Point mutations of the K-ras and adenomatous polyposis coli (APC) genes were studied by sequencing. RESULTS: The patients had varying degrees of dysplasia and one displayed DNA aneuploidy. Loss of heterozygosity at 5q15-22 was detected in three of five biopsies in one patient. This particular patient had no signs of dysplasia or DNA aneuploidy and a normal exon 15 sequence of the APC gene. No alterations of either the K-ras or the APC genes or LOH of 5q, 17p, or 18q were seen in any of the other patients. CONCLUSION: Dysplasia, aneuploidy, and LOH in 5q may all reflect different parts of an atrophic mucosa-dysplasia-carcinoma sequence, in line with current concepts of carcinogenesis for CRC in long-standing pouchitis. Further studies of histological and molecular events in IPAA patients with severe atrophy are warranted.


Assuntos
Transformação Celular Neoplásica/genética , DNA/genética , Mucosa Intestinal/patologia , Pouchite/patologia , Adulto , Aneuploidia , Transformação Celular Neoplásica/patologia , Criança , Colite Ulcerativa/cirurgia , Neoplasias Colorretais/etiologia , Neoplasias Colorretais/genética , DNA de Neoplasias/análise , Feminino , Genes APC , Genes ras/genética , Humanos , Mucosa Intestinal/metabolismo , Perda de Heterozigosidade , Masculino , Repetições de Microssatélites/genética , Mutação Puntual , Reação em Cadeia da Polimerase , Pouchite/complicações , Pouchite/genética , Fatores de Risco
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