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1.
J Toxicol Pathol ; 29(3): 163-71, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27559241

RESUMO

Histopathological and electrocardiographic features of myocardial lesions induced by combretastatin A4 disodium phosphate (CA4DP) were evaluated, and the relation between myocardial lesions and vascular changes and the direct toxic effect of CA4DP on cardiomyocytes were discussed. We induced myocardial lesions by administration of CA4DP to rats and evaluated myocardial damage by histopathologic examination and electrocardiography. We evaluated blood pressure (BP) of CA4DP-treated rats and effects of CA4DP on cellular impedance-based contractility of human induced pluripotent stem cell-derived cardiomyocytes (hiPS-CMs). The results revealed multifocal myocardial necrosis with a predilection for the interventricular septum and subendocardial regions of the apex of the left ventricular wall, injury of capillaries, morphological change of the ST junction, and QT interval prolongation. The histopathological profile of myocardial lesions suggested that CA4DP induced a lack of myocardial blood flow. CA4DP increased the diastolic BP and showed direct effects on hiPS-CMs. These results suggest that CA4DP induces dysfunction of small arteries and capillaries and has direct toxicity in cardiomyocytes. Therefore, it is thought that CA4DP induced capillary and myocardial injury due to collapse of the microcirculation in the myocardium. Moreover, the direct toxic effect of CA4DP on cardiomyocytes induced myocardial lesions in a coordinated manner.

2.
J Toxicol Pathol ; 27(3-4): 223-30, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25378807

RESUMO

The microtubule inhibitor colchicine is cardiotoxic and is suggested to impair impulse formation and conduction. However, little is known about the electrocardiographic (ECG) changes induced by colchicine in experimental animals and the detailed pathogenesis of its cardiotoxicity. Therefore, we analyzed cardiotoxicity in colchicine-treated rats using electrocardiographic, histopathological and blood-chemistry approaches. A telemetry device for transmitting ECG data was implanted into male Crl:CD(SD) rats, and ECG tracings were obtained. At 6 weeks of age, 1.25 mg/kg colchicine was injected intravenously once daily for 2 consecutive days, and ECG waveforms and heart rate variability were analyzed. Furthermore, 1.25 mg/kg colchicine or vehicle was injected for 1 or 2 consecutive days in other rats at 6 weeks of age. One day after the final dosing, heart and blood samples were taken for histopathological and bloodchemical examination. ECG analysis revealed a prolonged RR interval, QRS duration, PR interval and QT interval. Heart rate variability analysis showed an increase in high frequency (HF) components as an index of parasympathetic nervous activity. In blood chemical examinations, colchicine induced high levels of parameters of cardiac injury and low levels and/or variations in Ca, inorganic phosphorus, potassium and chloride. Histopathologically, colchicine-treated rats showed eosinophilic granular degeneration and cytoplasmic vacuolation of ventricular myocardial cells but no remarkable change in the atrioventricular node. Not only blood chemical and histopathological changes but also ECG changes were induced in colchicine-treated rats, which indicated a decrease in myocardium excitability and conductivity, and these changes might be related to increased parasympathetic nervous activity and low blood Ca levels.

3.
Toxicol Appl Pharmacol ; 274(2): 191-9, 2014 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-24161588

RESUMO

Protein fermentation by intestinal bacteria generates various compounds that are not synthesized by their hosts. An example is p-cresol, which is produced from tyrosine. Patients with chronic kidney disease (CKD) accumulate high concentrations of intestinal bacteria-derived p-cresyl sulfate (pCS), which is the major metabolite of p-cresol, in their blood, and this accumulation contributes to certain CKD-associated disorders. Immune dysfunction is a CKD-associated disorder that frequently contributes to infectious diseases among CKD patients. Although some studies imply pCS as an etiological factor, the relation between pCS and immune systems is poorly understood. In the present study, we investigated the immunological effects of pCS derived from intestinal bacteria in mice. For this purpose, we fed mice a tyrosine-rich diet that causes the accumulation of pCS in their blood. The mice were shown to exhibit decreased Th1-driven 2, 4-dinitrofluorobenzene-induced contact hypersensitivity response. The concentration of pCS in blood was negatively correlated with the degree of the contact hypersensitivity response. In contrast, the T cell-dependent antibody response was not influenced by the accumulated pCS. We also examined the in vitro cytokine responses by T cells in the presence of pCS. The production of IFN-γ was suppressed by pCS. Further, pCS decreased the percentage of IFN-γ-producing Th1 cells. Our results suggest that intestinal bacteria-derived pCS suppressesTh1-type cellular immune responses.


Assuntos
Bactérias/metabolismo , Cresóis/sangue , Sistema Imunitário/microbiologia , Intestinos/microbiologia , Ésteres do Ácido Sulfúrico/sangue , Células Th1/imunologia , Animais , Linfócitos T CD8-Positivos/imunologia , Dermatite de Contato/imunologia , Dermatite de Contato/patologia , Dinitrofluorbenzeno/efeitos adversos , Feminino , Interações Hospedeiro-Patógeno , Imunidade Celular/efeitos dos fármacos , Interferon gama/biossíntese , Interferon gama/sangue , Mucosa Intestinal/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Células Th1/efeitos dos fármacos , Tirosina/administração & dosagem
4.
Phytother Res ; 27(2): 299-305, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22566187

RESUMO

Guava leaf tea (GLT) contains guava leaf polyphenol (Gvpp), which regulates the absorption of dietary carbohydrate from the intestines. Borderline diabetics, who are at high risk of development of diabetes, take GLT to suppress a rapid increase of blood sugar level after meals. However, patients with diabetes in whom diabetic drugs or warfarin as a blood thinner are prescribed also take GLT with the expectation of glycemic control. Therefore, we studied whether GLT had potential for inhibition or induction of cytochrome P450 (CYP) and an influence on the action of warfarin. Extract of guava leaf (GvEx) consists of carbohydrate and polyphenols, which are Gvpp, quercetin, and ellagic acid. These polyphenols, but not GvEx, showed a certain level of inhibition of human-cDNA-expressed CYPs. In a comparison of GLT and grapefruit juice, GLT showed weaker inhibition of CYP activities and of midazolam 1'-hydroxylation than grapefruit juice. Furthermore, neither liver weight nor CYP3A expression in the liver was changed in rats that received GvEx for 90 days compared with the control group. When rats were concomitantly treated with GLT and warfarin, the prolongation of clotting time of blood by warfarin was not influenced. These data suggest that GLT is unlikely to interact with drugs.


Assuntos
Inibidores do Citocromo P-450 CYP3A , Interações Alimento-Droga , Polifenóis/farmacologia , Psidium/química , Varfarina/farmacologia , Animais , Bebidas , Citocromo P-450 CYP3A/metabolismo , Inibidores Enzimáticos/farmacologia , Humanos , Fígado/efeitos dos fármacos , Fígado/enzimologia , Masculino , Midazolam/metabolismo , Tempo de Tromboplastina Parcial , Ratos , Ratos Sprague-Dawley
5.
Exp Toxicol Pathol ; 65(6): 737-43, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23131582

RESUMO

Microtubule disassembling agents (MDAs) such as colchicine (COL) and vincristine sulfate (VCR) are known to be cardiotoxic. However, few attempts have been made to histopathologically examine cardiac lesions induced by MDAs. In this study, we endeavored to induce myocardial injury in rats by administering MDAs and to clarify the morphological features of these myocardial lesions. Male rats were intravenously administered COL (1.00 or 1.25mg/kg for 2 days at single daily doses) or VCR (0.50 or 0.75 mg/kg for 2 days at single daily doses). The day after administration, hearts were excised and examined histopathologically, immunohistochemically and electron microscopically. Degeneration and necrosis of myocardial cells with vacuolation were observed in rats administered COL at 1.25mg/kg or VCR at 0.75 mg/kg. Electron microscopic examination revealed vacuoles in swollen mitochondria. Moreover, there were cells showing pyknosis and karyorrhexis in the interstitium. TUNEL and immunohistochemical staining for endothelial cells and electron microscopic examination identified the apoptotic cells in the interstitium to be vascular endothelial cells. These vascular endothelial lesions were induced by lower doses of MDAs than were myocardial lesions. Furthermore, common sites of cardiac lesions induced by MDAs had almost the same distribution as areas positive for pimonidazole, a marker of hypoxia. These findings indicate that MDAs occasionally damage mitochondria in myocardial cells, and suggest that these changes involve microcirculatory dysfunction induced by endothelial cell injury.


Assuntos
Cardiomiopatias/induzido quimicamente , Colchicina/toxicidade , Microtúbulos/efeitos dos fármacos , Miocárdio/ultraestrutura , Moduladores de Tubulina/toxicidade , Vincristina/toxicidade , Animais , Apoptose/efeitos dos fármacos , Cardiomiopatias/patologia , Imuno-Histoquímica , Masculino , Microscopia Eletrônica de Transmissão , Microtúbulos/diagnóstico por imagem , Dilatação Mitocondrial/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Ultrassonografia
6.
Nephrol Dial Transplant ; 26(3): 1094-8, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20929916

RESUMO

BACKGROUND: para-Cresol, which is present in the blood mainly as p-cresyl sulphate, is a protein-bound uraemic toxin that is produced in the intestine by certain intestinal bacteria, and its production is affected by various intestinal environmental factors. Patients with end-stage renal disease who are undergoing haemodialysis (HD) often have defective bowel function leading to abnormal defecation. Since treatment with synbiotics (SYN), which are a combination of probiotics and prebiotics, is reported to improve bowel habit, we examined the effects of SYN on the serum p-cresol level in HD patients. METHODS: Nine HD patients received SYN (Lactobacillus casei strain Shirota and Bifidobacterium breve strain Yakult as probiotics and galacto-oligosaccharides as prebiotics) three times a day for 2 weeks. The duration of the study was 4 weeks (2 weeks of pretreatment observation and 2 weeks of treatment). The subjects were asked to complete a questionnaire about their bowel habits (defecation frequency, stool quantity, stool form and ease of defecation) during the study period. Serum p-cresol levels before and after SYN treatment were determined. RESULTS: According to the questionnaire conducted during the pretreatment observation period, HD patients with a high serum p-cresol level tended to have hard stools with difficulty in defecation. With SYN treatment, stool quantity increased significantly and hard, muddy or soft stools tended to be replaced by normal ones. The serum p-cresol level also decreased significantly. CONCLUSIONS: It was found that uraemic toxin, p-cresol, was associated with constipation and that SYN treatment resulted in normalization of bowel habits and a decrease of serum p-cresol levels in HD patients. Therefore, SYN treatment may be anticipated to reduce the toxic effect of p-cresol in HD patients.


Assuntos
Cresóis/sangue , Falência Renal Crônica/terapia , Diálise Renal , Simbióticos/estatística & dados numéricos , Administração Oral , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Rejeição de Enxerto/prevenção & controle , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco , Inquéritos e Questionários , Taxa de Sobrevida
7.
Cancer Chemother Pharmacol ; 67(1): 201-13, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20354702

RESUMO

Irinotecan hydrochloride (CPT-11) is a useful drug for cancer chemotherapy but sometimes induces severe diarrhea clinically. CPT-11 is mainly activated to SN-38 by carboxylesterase (CES) and then detoxified to SN-38 glucuronide (SN-38G) by UDP-glucuronosyltransferase (UGT) in the liver. SN-38G is excreted via bile and de-conjugated to SN-38 by ß-glucuronidase (ß-GLU) in the intestinal content. In order to clarify the alleviative effect of antibiotics on CPT-11-induced diarrhea, we examined whether penicillin G and streptomycin (SM) alleviate CPT-11-induced delayed-onset diarrhea using three diarrheal models, i.e., Wistar rats with repeated dosing of CPT-11 (60 mg/kg/day i.v. for 4 consecutive days) and Wistar and Gunn rats with a single dosing of CPT-11 (200 and 20 mg/kg i.v., respectively). Gunn rats have an inherited deficiency of UGT1A and cannot conjugate SN-38 to SN-38G. Therefore, onset of CPT-11-induced diarrhea in Gunn rats is not affected by ß-GLU activity. SM alleviated diarrhea in all three diarrheal models. The alleviation of diarrhea by SM in Gunn rats indicated that the effect of SM occurred by a mechanism other than the inhibition of ß-GLU activity. SM decreased CPT-11 and/or SN-38 concentrations in intestinal tissues and alleviated epithelial damage from the ileum to colon. SM did not inhibit ß-GLU activity in the cecal content. SM also inhibited the intestinal absorption of CPT-11 and decreased CES activity and increased UGT activity in the intestinal epithelium. These findings indicated that SM decreased the exposure of CPT-11 and SN-38 to the intestinal epithelium by inhibiting the absorption of CPT-11 from the intestinal lumen and the change of CES and UGT activities in the intestinal epithelium and alleviated delayed-onset diarrhea.


Assuntos
Antibacterianos/farmacologia , Antineoplásicos Fitogênicos/toxicidade , Camptotecina/análogos & derivados , Diarreia/prevenção & controle , Estreptomicina/farmacologia , Animais , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/farmacocinética , Camptotecina/administração & dosagem , Camptotecina/farmacocinética , Camptotecina/toxicidade , Diarreia/induzido quimicamente , Glucuronidase/antagonistas & inibidores , Glucuronidase/metabolismo , Glucuronosiltransferase/efeitos dos fármacos , Glucuronosiltransferase/metabolismo , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Irinotecano , Masculino , Penicilina G/farmacologia , Ratos , Ratos Gunn , Ratos Wistar , Fatores de Tempo
8.
J Toxicol Pathol ; 24(4): 251-5, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22319239

RESUMO

A subcutaneous tumor was found in the right abdomen of a 16-week-old male TCRß and p53 double-knockout mouse. The tumor had indistinct borders with the surrounding tissue. The cut surface after formalin fixation was pale yellowish white, partially dark red and partly white. Histologically, the tumor was composed of three distinct regions. The first region showed pleomorphic cells arranged in sheets. The second region showed spindle cells arranged in interlacing fascicles. The final region contained a mixture of the above mentioned two types of cells. Furthermore, a small amount of collagen fibers, round cells, multinucleated giant cells, and cells with eosinophilic granules were observed between these tumor cells. Immunohistochemical examination and electron microscopy identified that the pleomorphic cells and spindle cells were histiocytes and fibroblasts, respectively, and that the round cells were undifferentiated mesenchymal cells. Based on these findings, the tumor was diagnosed as a malignant fibrous histiocytoma.

9.
BMC Cancer ; 9: 157, 2009 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-19460136

RESUMO

BACKGROUND: Thymidylate synthase (TS) is known to have a unique 28 bp tandemly repeated sequence in the promoter region, and the majorities of subjects have a heterozygous double repeat/triple repeat genotype in their non-cancerous tissue. Loss of heterozygosity (LOH) at the TS locus is known to occur in cancer patients, but there is no evidence that it is present in precancerous tissue. The aim of this study was to analyze the frequency and timing of LOH at the TS locus in Barrett-associated adenocarcinoma (BA) and its precursory lesions, such as intestinal metaplasia (IM) and dysplasia. METHODS: One hundred twenty-three samples (including 37 with gastroesophageal reflux disease (GERD), 29 with IM, 13 with dysplasia, and 44 with BA) were obtained from 100 patients. Biopsies were obtained from the lower esophageal mucosa/IM/dysplasia/BA, when available. Normal squamous tissue from the upper esophagus was taken as a control. All tissues were analyzed for the TS genotype and TS mRNA expression using the real-time reverse-transcription polymerase chain reaction (RT-PCR) method after laser-capture microdissection. RESULTS: Among the patients with informative heterozygous genotype in their control samples, no sample with LOH at the TS locus was observed in the lower esophageal mucosa in GERD patients (0/22 samples). However, 6 out of 21 samples (28.6%) had LOH in IM, 2 of 7 (28.6%) in dysplasia, and 10 of 25 (40.0%) in BA. No significant difference in TS mRNA expression levels was observed between TS genotypes. CONCLUSION: Our results demonstrate that LOH is a relatively frequent and early event in the IM-BA sequence.


Assuntos
Adenocarcinoma/genética , Esôfago de Barrett/genética , Hiperplasia/genética , Perda de Heterozigosidade , Metaplasia/genética , Timidilato Sintase/genética , Adenocarcinoma/patologia , Idoso , Esôfago de Barrett/patologia , Progressão da Doença , Esôfago/patologia , Feminino , Humanos , Hiperplasia/patologia , Masculino , Metaplasia/patologia , Pessoa de Meia-Idade , Processos Neoplásicos
10.
Immunopharmacol Immunotoxicol ; 31(2): 304-9, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19235606

RESUMO

p-Cresol, an end product of aromatic amino acids, is produced from food proteins by intestinal bacteria, and is detectable in blood and feces. Especially, blood and fecal levels of p-cresol are high in chronic renal failure (CRF) patients. Although it has been suggested that p-cresol is toxic in the body, the effect of p-cresol on immune responses has not yet been clarified. In this study, we investigated the effect of p-cresol on IL-12 production of macrophages stimulated with Lactobacillus casei strain Shirota (LcS) in vitro. Pre-incubation with p-cresol inhibited IL-12 p40 production of LcS-stimulated J774.1 cells, a murine macrophage-like cell line, in a dose-dependent manner. IL-12 p40 and p70 production of LcS-stimulated murine peritoneal macrophages was also inhibited by p-cresol. The inhibitory effect was not dependent on the cytotoxicity of p-cresol. These results indicate that blood and fecal p-cresol may have adverse effects on the host defense system in CRF patients.


Assuntos
Cresóis/toxicidade , Interleucina-12/antagonistas & inibidores , Macrófagos/efeitos dos fármacos , Animais , Células Cultivadas , Cresóis/metabolismo , Imunização , Interleucina-12/biossíntese , Falência Renal Crônica/imunologia , Lacticaseibacillus casei/imunologia , Macrófagos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C
11.
J Toxicol Pathol ; 22(1): 83-7, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22271980

RESUMO

Cardiac hypertrophy was observed in a 9-week-old Crl:CD(SD) rat that died unexpectedly. The animal was allocated to the control group of a toxicity study, and no abnormalities in its general conditions, body weight or food intake were observed. Necropsy revealed an increase in heart weight. Gross examination indicated cardiac enlargement with thickening of the right and left ventricular walls. Histopathological examination revealed hypertrophy of the cardiomyocytes in the right and left ventricular walls and the interventricular septum. Electron microscopic examination indicated bizarre nuclei and accumulation of an increased number of various sizes of mitochondria in the perinuclear region of the hypertrophied myocytes. Hypertrophied myocytes connected by intensely folded intercalated disks were also observed. Based on these findings, the animal was diagnosed with cardiac hypertrophy. This is the first case report of cardiac hypertrophy in this strain.

12.
BMC Cancer ; 8: 386, 2008 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-19105824

RESUMO

BACKGROUND: Over-expression of thymidylate synthase (TS) and dihydropyrimidine dehydrogenase (DPD) in tumor tissue is associated with insensitivity to 5-fluorouracil (5-FU). Over-expression of ERCC1 correlates with insensitivity to oxaliplatin (OX) therapy, while high thymidine phosphorylase (TP) levels predict for increased sensitivity to capecitabine (Xel). METHODS: Biopsies of metastatic tumor were taken before OX (130 mg/m2 day 1) given with Xel (1200-3000 mg/m2 in two divided doses days 1-5 and 8-12) every 3-weeks. Micro-dissected metastatic and primary tumors were analyzed for relative gene expression by real-time quantitative polymerase chain reaction. The clinical protocol prospectively identified the molecular targets of interest that would be tested. Endpoints for the molecular analyses were correlation of median, first and third quartiles for relative gene expression of each target with response, time to treatment failure (TTF), and survival. RESULTS: Among 91 patients participating in this trial; 97% had colorectal cancer. The median number of prior chemotherapy regimens was 2, and most had prior 5-FU and irinotecan. In paired samples, median mRNA levels were significantly higher in metastatic versus primary tumor (-fold): TS (1.9), DPD (3.8), ERCC1 (2.1) and TP (1.6). A strong positive correlation was noted between DPD and TP mRNA levels in both primary (r = 0.693, p < 0.0005) and metastatic tissue (r = 0.697, p < 0.00001). There was an association between TS gene expression and responsive and stable disease: patients whose intratumoral TS mRNA levels were above the median value had significantly greater risk of early disease progression (43% vs 17%), but this did not translate into a significant difference in TTF. ERCC1 gene expression above the third quartile was associated with a shorter TTF (median 85 vs 162 days, p = 0.046). Patients whose TS mRNA levels in metastatic tumor tissue were below the median had a longer overall survival (median 417 vs 294 days, p = 0.042). CONCLUSION: Target gene expression in primary tumor was significantly lower than that in paired metastatic tissue. High ERCC1 mRNA levels in metastatic tumor was associated with a shorter TTF. Lower expression of TS mRNA correlated with a lower chance of early PD with XelOX therapy and improved overall survival.


Assuntos
Neoplasias Colorretais/genética , Proteínas de Ligação a DNA/análise , Di-Hidrouracila Desidrogenase (NADP)/análise , Endonucleases/análise , Proteínas de Neoplasias/análise , Timidina Fosforilase/análise , Timidilato Sintase/análise , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Capecitabina , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/mortalidade , Proteínas de Ligação a DNA/genética , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Esquema de Medicação , Resistencia a Medicamentos Antineoplásicos , Endonucleases/genética , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/análogos & derivados , Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas de Neoplasias/genética , Compostos Organoplatínicos/administração & dosagem , Oxaliplatina , RNA Mensageiro/análise , Análise de Sobrevida , Timidina Fosforilase/genética , Falha de Tratamento
13.
Gan To Kagaku Ryoho ; 35(8): 1435-8, 2008 Aug.
Artigo em Japonês | MEDLINE | ID: mdl-18701867

RESUMO

We described 3 cases of stomatitis caused by chemotherapy with the fluoropyrimidine preparation S-1, alone or combined with other anticancer drugs. The stomatitis did not respond to conventional oral mucosal treatment such as triamcinolone acetonide(Kenalog)or allopurinol, but improved after treatment with the histamine H2-receptor antagonist lafutidine. The concurrent use of lafutidine allowed these 3 patients to continue chemotherapy with no recurrence of stomatitis. We concluded that lafutidine may be a viable treatment option for chemotherapy-induced stomatitis, allowing treatment to be continued.


Assuntos
Acetamidas/uso terapêutico , Neoplasias Gastrointestinais , Piperidinas/uso terapêutico , Piridinas/uso terapêutico , Estomatite/complicações , Estomatite/tratamento farmacológico , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Gastrointestinais/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade
14.
Cancer Chemother Pharmacol ; 63(1): 85-9, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18309485

RESUMO

PURPOSE: Although the prognosis in patients with pancreatic cancer has been poor, we recently reported unusually high response rate and survival benefit of S-1 treatment in patients with pancreatic cancer. The aim of this study was to reveal genetic background of this unique activity of S-1 against pancreatic cancer. S-1 is a novel oral fluoropyrimidine derivative consisting of Tegafur (FT) and dihydropyrimidine dehydrogenase (DPD) inhibitor (5-chloro-2,4-dihydroxypyridine; CDHP). Accordingly, intratumoral DPD mRNA expression level was measured to reveal whether the level in pancreatic cancer was different from other GI cancer and whether it was relevant to chemosensitivity. METHODS: Thirty-three recurrent pancreatic cancer patients treated with S-1 were studied. We obtained 15 responders and 13 non-responders according to the change of serum CA19-9. The mRNA was extracted from paraffin-embedded surgical specimens using laser captured microdissection, and relative expression levels of each DPD/beta-actin were measured using a quantitative reverse transcription polymerase chain reaction (RT-PCR) (Taqman) system. Forty-four colorectal cancer patients and 20 gastric cancer patients treated with S-1 were enrolled as control groups. Thymidylate synthase (TS) mRNA expression levels were also measured. RESULTS: Intratumoral DPD mRNA expression level was significantly higher in pancreatic cancer than that in colorectal cancer (P = 0.0003; median level, 1.38 vs. 0.44) and gastric cancer (P = 0.0061; 1.38 vs. 0.82). No difference in TS mRNA expression levels was observed among cancer types. DPD expression among responded pancreatic cancer was significantly lower than non-responded. (P = 0.012, Mann-Whitney U test). CONCLUSIONS: Intratumoral DPD mRNA expression level in pancreatic cancer was significantly higher than the other malignancies. This result may elucidate possible reasons for the high effectiveness of S-1 in pancreatic cancer.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Di-Hidrouracila Desidrogenase (NADP)/genética , Proteínas de Neoplasias/genética , Neoplasias Pancreáticas/enzimologia , RNA Mensageiro/análise , RNA Neoplásico/análise , Adenocarcinoma/enzimologia , Adenocarcinoma/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/sangue , Antígeno CA-19-9/sangue , Cisplatino/administração & dosagem , Neoplasias Colorretais/enzimologia , Neoplasias Colorretais/genética , Di-Hidrouracila Desidrogenase (NADP)/biossíntese , Combinação de Medicamentos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas de Neoplasias/biossíntese , Ácido Oxônico/administração & dosagem , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias Gástricas/enzimologia , Neoplasias Gástricas/genética , Tegafur/administração & dosagem , Resultado do Tratamento
15.
Cancer Chemother Pharmacol ; 61(4): 595-605, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17549477

RESUMO

We assessed the involvement of UDP-glucuronosyltransferase (UGT) activity in episodes of irinotecan hydrochloride (CPT-11)-induced delayed-onset diarrhea using a mutant rat strain with an inherited deficiency of UGT1A (Gunn rats). Gunn rats exhibited severe diarrhea after the intravenous administration of CPT-11 at a dose of 20 mg/kg, whereas Wistar rats did not. In the epithelium of the small intestine and cecum in Gunn rats, the shortening of villi, degeneration of crypts, and destruction of the nucleus were observed. The AUC, MRT, and t (1/2) of CPT-11, and the AUC of 7-ethyl-10-hydroxycamptothecin (SN-38) in plasma were, respectively, 1.6-fold, 1.5-fold, 1.7-fold, and 6.5-fold higher, and the cumulative biliary excretion rate of SN-38 was 2.3-fold higher, in Gunn rats than Wistar rats. SN-38 glucuronide excreted via bile in Wistar rats was not de-conjugated in the small intestinal lumen. The SN-38 AUC values in small intestinal tissues were also 5.0 to 5.8-fold higher in Gunn rats than Wistar rats. In conclusion, Gunn rats developed severe delayed-onset diarrhea after i.v. administration of CPT-11 at a much lower dose. Severe intestinal impairments would be induced in Gunn rats through exposure to SN-38 at high levels for a long period mainly via the intestinal lumen and partially via the bloodstream. These results clarified that the deficiency of UGT activity contributed greatly to the induction of the CPT-11-induced delayed-onset diarrhea and epithelial impairment in the intestine. In the clinic, great care is needed when using chemotherapy with CPT-11 in patients with poor UGT activity.


Assuntos
Antineoplásicos Fitogênicos/toxicidade , Camptotecina/análogos & derivados , Diarreia/induzido quimicamente , Diarreia/enzimologia , Glucuronosiltransferase/metabolismo , Algoritmos , Animais , Antineoplásicos Fitogênicos/farmacocinética , Área Sob a Curva , Bilirrubina/metabolismo , Camptotecina/metabolismo , Camptotecina/farmacocinética , Camptotecina/toxicidade , Síndrome de Crigler-Najjar/enzimologia , Síndrome de Crigler-Najjar/genética , Diarreia/patologia , Glucuronosiltransferase/deficiência , Glucuronosiltransferase/genética , Hiperbilirrubinemia/enzimologia , Hiperbilirrubinemia/genética , Intestinos/patologia , Irinotecano , Ratos , Ratos Gunn , Ratos Wistar
16.
J Cancer Res Clin Oncol ; 133(11): 841-6, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17479286

RESUMO

PURPOSE: We evaluate the feasibility and efficacy of S-1 in combination with cisplatin (CDDP) for patients with colorectal cancer. METHODS: A total of 52 patients with advanced or recurrent colorectal cancer were included. S-1 was given orally twice daily for 21 days and CDDP 30 mg/m(2) on day 1 and 8, followed by a 2-week period of no treatment. RESULTS: Tumor responses among patients included 18 PR, 12 SD, and 16 PD (n = 46). The overall response rate was 36.4% (18/46). The response rate of the patients with prior chemotherapy was 22.2% (4/18) and 50.0% (12/24) among the patients who had no prior therapy. The median survival periods were 555 days and the median progression free survival periods were 183 days, respectively. S-1 in combination with CDDP shows promising activity with acceptable toxicities against colorectal cancer. CONCLUSIONS: A combination of S-1 and CDDP could be a standard therapy for treating colorectal carcinoma.


Assuntos
Adenocarcinoma/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Cisplatino/administração & dosagem , Neoplasias Colorretais/patologia , Intervalo Livre de Doença , Combinação de Medicamentos , Feminino , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Ácido Oxônico/administração & dosagem , Taxa de Sobrevida , Tegafur/administração & dosagem , Resultado do Tratamento
17.
Int J Cancer ; 119(3): 522-6, 2006 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-16572420

RESUMO

Gene expression levels of thymidylate synthase (TS), dihydropyrimidine dehydrogenase (DPD), thymidine phosphorylase (TP) and orotate phosphoribosyl transferase (OPRT) have been shown to be associated with response to 5-fluorouracil-based therapies. Analyzing these gene expression levels in liver metastases is important to obtain the best prediction of therapy. Our aim was to determine how TS, DPD, TP and OPRT gene expression levels in primary colorectal cancer (CRC) were related to those in liver metastases. Formalin-fixed, paraffin-embedded tumor specimens from 31 pairs of primary CRC and corresponding liver metastases were dissected by using laser-captured microdissection. RNA was extracted and cDNA was prepared by reverse-transcription. Quantitation of target gene and internal reference gene was performed using real-time PCR. No significant difference was seen between median mRNA expression levels of TS, DPD, TP and OPRT in primary cancer and those in corresponding liver metastases (median value: TS 1.48 vs. 1.43; p=0.92, DPD 0.19 vs.0.12; p=0.10, TP 1.20 vs. 0.98; p=0.39, OPRT 1.17 vs. 0.95; p=0.10). When matched tissue sets were compared on an individual basis, there was a significant correlation for TS mRNA expression between primary cancer and corresponding liver metastases (rs=0.52, p=0.0026). However, no correlation was seen between matched sets for DPD, TP or OPRT. Significant correlation was seen between DPD and TP expression levels in both primary CRC (rs=0.38, p=0.03) and liver metastases (rs=0.72, p<0.0001). A good prediction of TS mRNA levels in liver metastases can be obtained by measuring those of primary CRC, although no correlation was seen for DPD, TP and OPRT.


Assuntos
Neoplasias Colorretais/genética , Regulação Enzimológica da Expressão Gênica/genética , Regulação Neoplásica da Expressão Gênica/genética , Neoplasias Hepáticas/genética , Idoso , Idoso de 80 Anos ou mais , Colo/efeitos dos fármacos , Colo/enzimologia , Colo/metabolismo , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Di-Hidrouracila Desidrogenase (NADP)/genética , Feminino , Fluoruracila/uso terapêutico , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Fígado/efeitos dos fármacos , Fígado/enzimologia , Fígado/metabolismo , Neoplasias Hepáticas/secundário , Masculino , Pessoa de Meia-Idade , Orotato Fosforribosiltransferase/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reto/efeitos dos fármacos , Reto/enzimologia , Reto/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Timidina Fosforilase/genética , Timidilato Sintase/genética
18.
Int J Cancer ; 119(4): 765-70, 2006 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-16550596

RESUMO

Previous studies from our laboratory and others have suggested that increased expression of cox-2 is important in the genesis of esophageal adenocarcinoma. In vitro studies suggest that cox-2 regulates expression of the anti-apoptotic protein bcl-2, thus possibly accounting for reduced apoptosis in carcinogenesis. The aim of this study was to investigate the relationship of these 2 genes in the development of Barrett's-associated adenocarcinoma. Histologic sections from endoscopic biopsies or esophagectomy specimens were classified as non-dysplastic Barrett's (n = 30), intraepithelial neoplasia (n = 12) and adenocarcinoma (n = 48). The desired tissue was isolated by laser capture microdissection and expression levels of cox-2 and bcl-2 were measured by quantitative real-time PCR (Taqman). Gene expression levels were compared to samples of the distal esophageal squamous epithelium (n = 55) and reflux-esophagitis (n = 25), without Barrett's or cancer. Expression of both bcl-2 and cox-2 were increased in non-dysplastic Barrett's (p = 0.0077, p = 0.0037), intraepithelial neoplasia (p = 0.0053, p = 0.0220) and adenocarcinoma (p < 0.0001, p < 0.0001) compared to squamous epithelium or reflux-esophagitis. Furthermore, there is a significant correlation between these two genes, especially in carcinoma (p < 0.0001).


Assuntos
Adenocarcinoma/genética , Adenocarcinoma/patologia , Esôfago de Barrett/genética , Esôfago de Barrett/patologia , Ciclo-Oxigenase 2/genética , Regulação Neoplásica da Expressão Gênica , Proteínas Proto-Oncogênicas c-bcl-2/genética , Adenocarcinoma/enzimologia , Esôfago de Barrett/enzimologia , Progressão da Doença , Humanos
20.
Clin Cancer Res ; 12(1): 29-33, 2006 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-16397020

RESUMO

PURPOSE: Increased vascular endothelial growth factor (VEGF) expression is associated with colorectal cancer liver metastases. It is reasonable to expect that measurement of VEGF in liver metastases would provide the best prediction of therapy benefit for VEGF-targeted drugs, such as bevacizumab (Avastin). In this study, we evaluated how VEGF mRNA level in primary colorectal cancer was related to that in corresponding liver metastases. Thirty-one pairs of primary colorectal cancer and corresponding liver metastases were analyzed. EXPERIMENTAL DESIGN: Formalin-fixed, paraffin-embedded tumor specimens were dissected by using laser-captured microdissection. RNA was extracted and cDNA was prepared by reverse transcription. Quantitation of VEGF and internal reference gene (beta-actin) was done using real-time PCR (Taqman PCR). RESULTS: There was no difference between median VEGF mRNA levels of primary colorectal cancer and liver metastases (median value 3.79 versus 3.97: P = 0.989). On an individual basis, there was a significant correlation in VEGF mRNA expression between primary colorectal cancer and corresponding liver metastases (r(s) = 0.6627, P < 0.0001). In addition, the VEGF mRNA levels of the patients who had two or more liver metastatic tumors were significantly higher than those of the patient who had solitary liver metastatic tumor in both primary cancer (5.02 versus 3.34: P = 0.0483) and liver metastases (4.38 versus 3.25: P = 0.0358). CONCLUSION: Good prediction of VEGF mRNA levels in liver metastases can be obtained by measuring those of primary colorectal cancer. The risk of multiple liver metastatic tumors might be predictable by measuring VEGF mRNA expression in primary colorectal cancer. Further study is required to confirm these preliminary results.


Assuntos
Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/secundário , Fator A de Crescimento do Endotélio Vascular/biossíntese , Idoso , Idoso de 80 Anos ou mais , Feminino , Expressão Gênica , Humanos , Masculino , Microdissecção , Pessoa de Meia-Idade , RNA Mensageiro , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator A de Crescimento do Endotélio Vascular/genética
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