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1.
Protein-bound polyamines were isolated from the plasma of mice using antipolyamine antibodies covalently linked to magnetic latex spheres. Their subsequent separation by polyacrylamide gel electrophoresis (PAGE) showed that in plasma from normal mice, 3 proteins (27, 55 and 82 kDa) carrying polyamines could be visualized, whereas in mice bearing the Lewis lung carcinoma at least 8 other proteins of higher molecular mass (5 of 94, 110, 130, 145 and 160 kDa, and 3 of greater than 170 kDa) had bound polyamines. These protein-bound polyamines could be detected from the first week after tumour graft; they increased during the second and third week but decreased thereafter. These proteins were not bound by immunolatex spheres preincubated with spermine bound to a protein-carrier insulin. Moreover, the appearance of these protein-bound polyamines was not a consequence of the inflammatory process since in mice infected with heat-inactivated Brucella abortus, with the exception of a 65 kDa protein, polyamines were bound to the same proteins found in normal mice. In mice grafted with the Lewis lung carcinoma the concomitant decrease in transglutaminase-mediated polyamine (e.g. putrescine) binding capacity of plasma proteins provides additional evidence for the presence in vivo of polyamines already bound to plasma proteins.  相似文献   

2.
The isolation of polyamines from urinary hydrolysates in a sufficiently pure state for subsequent analysis by gas chromatography has proved to be difficult. However, by using columns of Porapak-Q and ion-exchange resins, urinary hydrolysates are readily purified and formation of trifluoroacetyl derivatives of polyamines proceeds in high yield without carryover of artifacts in the gas chromatographic elution profile. Good yields from the trifluoroacetylation reaction are not achieved if large quantities of salts or urinary pigments are present. By obtaining the polyamine carbonates in the final stages of the method described, the trifluoroacetylation reaction yields excellent derivatives of nanogram or microgram amounts, particularly after standing over-night at room temperature. The procedure described in detail should permit routine urinary polyamine analysis where rapidity, ease of handling many samples, freedom from complications and artifacts are a consideration. The recent reports by Russell1, 2 that the urinary excretion of polyamines are greatly elevated in cancer patients has stimulated interest in these compounds as possible biological “markers” for the diagnosis of cancer. The polyamines usually considered are: putrescine, 1, 4-diaminobutane; cadaverine, 1, 5-diaminopentane; spermidine, and spermine. An extensive literature has developed over the last 50 years concerning the isolation and determination of polyamines including many excellent reviews. 3–5 However, the isolation and determination of small quantities of polyamines from biological sources has proven to be difficult. This has led to conflicting conclusions among investigators as to which polyamine is the major excretion product in the urine of cancer patients. 2, 6, 7, 8 The following report presents in detail a new procedure of isolation of urinary polyamines in high yield and pure state that facilitates quantitation of these amines by gas chromatography.  相似文献   

3.
The effects of polyamines on DNA synthesis in vitro using various subcellular DNA polymerase fractions from normal and tumour-bearing rat livers, and tumour cells were investigated. When nuclear and mitochondrial DNA polymerase fractions were used, DNA synthesis on activated DNA was increased 3.5-8-fold by the addition of 20 mM putrescine or cadaverine. However, DNA synthesis was not stimulated by the addition of spermidine or spermine at any concentration tested. In contrast, DNA synthesis using the cytoplasmic DNA polymerase fraction was not stimulated at various concentrations of any of the four polyamines tested. The stimulatory effects of putrescine and cadaverine were absent when nuclear fractions from tumour-bearing rat liver or from tumour cells were used. In addition, in vitro DNA synthesis was not stimulated by 20 mM putrescine or cadaverine when nuclear extracts from the livers of rats administered putrescine subcutaneously were used. The specific activities of DNA polymerases extracted from tumour cells and tumour-bearing rat liver were already fully stimulated. These results suggest that DNA polymerases in tumour cells and tumour-bearing liver cells are stimulated by trapped putrescine produced in tumour cells and are thus no longer activated by exogenous putrescine.  相似文献   

4.
The significance of neuron-specific enolase (NSE) in the diagnosis and treatment monitoring of lung cancer was investigated in comparison with such established tumour markers as carcinoembryonic antigen (CEA), tissue polypeptide antigen (TPA), ferritin and calcitonin. We determined the serum concentrations of these tumour markers in 25 patients with small cell lung cancer (SCLC), 30 patients with non small cell lung cancer (NSCLC), and 38 patients with benign pulmonary diseases (BPD). In 14 patients with lung cancer, it was possible to follow up the behaviour of the tumour markers under treatment for up to 16 months. Calcitonin proved to have a surprisingly low sensitivity for SCLC. The utility of TPA and of ferritin was restricted, although the sensitivity was comparably high, by the high rate of false positive results. For NSCLC, CEA proved to be the best tumour marker. At present, NSE appears to be the tumour marker with the greatest specificity and sensitivity for SCLC. Its determination in the diagnosis, treatment and follow-up of SCLC makes good sense.  相似文献   

5.
Mammary epithelial cells were isolated from either abdominal-inguinal glands or mammary tumours of rats, after enzymic digestion of the tissues, and were analysed for polyamine content. Optimum conditions were developed for the isolation of cells in sufficient yield for the analysis of polyamines from 1 g of mammary gland or 0.5 g of tumour tissue. Complete recoveries of the polyamines in the tissues were achieved in the isolated epithelial cells.  相似文献   

6.
Pathological assessment of excised tumour and surgical margins in colorectal cancer (CRC) play crucial role in prognosis after surgery. Molecular assessment of margins could be more sensitive and informative than conventional histopathological analysis. Considering this view, we evaluated the distal surgical margins for expression of cancer stem cell (CSC) markers. Cellular and molecular assessment of normal, tumour and distal margin tissues were performed by flow cytometry, real‐time q‐PCR and immuno‐histochemical analysis for CRC patients after tumour excision. CRC patients were evaluated for expression of CSC markers in their normal, tumour and distal tissues. Flow cytometry assay revealed CD133 and CD44 enriched cells in distal margin and tumour compared to normal colorectal tissues, which was further confirmed by immunohistochemistry. Most importantly, immunohistochemistry also revealed the enrichment of CSC markers expression in pathologically negative distal margins. Patients with distal margin enriched for CD133 expression showed an increased recurrence rate and decreased disease‐free survival. This study proposes that although distal margin seems to be tumour free in conventional histopathological analysis, it could harbour cells enriched for CSC markers. Further CD133 could be a promising molecule to be used in molecular pathology for disease prognosis after surgery in CRC patients.  相似文献   

7.
Circulating tumour cells (CTCs) are independent predictor of prognosis in metastatic breast cancer. Nevertheless, in one third of patients, circulating tumour cells are undetected by conventional methods. Aim of the study was to assess the prognostic value of circulating tumour cells expressing mesenchymal markers in metastatic breast cancer patients. We isolated CTC from blood of 55 metastatic breast cancer patients. CTC were characterized for cytokeratins and markers of epithelial mesenchymal transition. The gain of mesenchymal markers in CTC was correlated to prognosis of patients in a follow-up of 24 months. The presence of mesenchymal markers on CTC more accurately predicted worse prognosis than the expression of cytokeratins alone. Because of the frequent loss of epithelial antigens by CTC, assays targeting epithelial antigens may miss the most invasive cell population. Thus, there is an urgent need to improve detection methods to identify CTC which undergone epithelial mesenchymal transition program.  相似文献   

8.
Transglutaminase activity and the levels of the polyamines putrescine, spermidine and spermine were measured in two transplantable rat sarcomata: P8 which metastasises consistently to the lung, and P7 which metastasises infrequently. With the P7 sarcoma no metastases were detected following implantation; similarly, no significant changes occurred in the levels of transglutaminase activity, putrescine, spermidine or spermine during tumour growth. However, with the P8 sarcoma at approx. 30 days after implantation there was a marked decrease in transglutaminase activity, mirrored exactly by a 20-fold increase in the levels of acid-soluble putrescine. Measurement of covalently-bound polyamines in the P8 sarcoma indicated a significant and corresponding decrease in the levels of bound putrescine. The timing of these changes coincided with the time at which the P8 sarcoma was shown to have metastasised, and suggests that the changes observed may be related to this phenomenon.  相似文献   

9.
植物源食品多胺的作用及其含量调节   总被引:9,自引:0,他引:9  
多胺 (polyamines,PAs)在植物源食品中广泛分布 ,在人体健康中发挥着重要作用。简要概述了多胺在细胞增殖、肿瘤发展中的作用及其作用的初步机理。通过化学调控和基因工程手段以及一些环境条件的控制 ,可以人为地调节植物源食品多胺的含量。  相似文献   

10.
多胺(polyamines, PAs)在植物源食品中广泛分布,在人体健康中发挥着重要作用。简要概述了多胺在细胞增殖、肿瘤发展中的作用及其作用的初步机理。通过化学调控和基因工程手段以及一些环境条件的控制,可以人为地调节植物源食品多胺的含量。  相似文献   

11.
1. Extracts prepared from tumours of the mouse colon induced by 1,2-dimethylhydrazine were considerably more active in catalysing the methylation of tRNA than were extracts from normal colon. The enhanced activity was observed when both unfractionated ;methyl-deficient' tRNA and purified tRNA preparations from yeast and bacteria were used as substrates for methylation. 2. The methylated bases produced in these reactions were identified. There were no differences between the products of the reaction catalysed by extracts of tumour and normal colon. 3. The increased activity of tRNA methylases was not due to the presence in the extracts of stimulatory or inhibitory molecules of low molecular weight such as polyamines or S-adenosylhomocysteine. 4. Other enzymes concerned with tRNA metabolism (RNA polymerase, ATP-tRNA adenylyltransferase, aminoacyl-tRNA ligases) were also increased in activity in the tumour tissue. 5. The extent of methylation of a limiting amount of tRNA was greater when tumour extracts were compared with controls, but in no case was it possible to achieve a stoicheiometric methylation of the purified tRNA preparations used as substrates, and the tumour extracts were not able to methylate tRNA obtained from normal mouse colon. We conclude that the tumours contained greater activities of tRNA methylases but that there was no evidence for changes in the specificity of these enzymes during neoplastic growth.  相似文献   

12.
The management of ovarian germ cell tumours (GCTs) has changed dramatically over the last 15 years. The combination of the introduction of tumour markers which accurately monitor the behaviour of the majority of germ cell tumours together with the introduction of newer chemotherapeutic agents has meant that few patients even with metastases should succumb from their disease. The tumour markers, human chorionic gonadotrophin (hCG) and alpha-foetoprotein (AFP) and, to a lesser extent, lactate dehydrogenase (LDH) and placental alkaline phosphatase (PLAP) are routinely used in assisting diagnosis, monitoring response to treatment and increasing the sensitivity of follow-up of patients after completing treatment. Analysis of our last 51 patients with all cell types of ovarian germ cell tumour has confirmed the importance of both hCG and AFP in that 45 (88%) of 51 patients had either or both of these tumour markers raised at the start of treatment for metastatic disease. Our data on LDH is incomplete since this has not been a routine assay until 1984 and, of the patients with active disease 10 (48%) had raised LDH at the start of treatment. PLAP has also been measured in a number of patients both on active treatment and in remission. 11 (50%) had raised levels of PLAP at the start of treatment but there was also a false positive rate of 8 (24%) of the 33 patients who were in remission and had not subsequently relapsed.  相似文献   

13.
Spermine, spermidine, putrescine and cadaverine are aliphatic amines widely spread in the human body. Their concentrations together with their acetyl conjugates increase significantly in the biological fluids and the affected tissues of cancer patients. Their concentrations decrease with the improvement in the patient’s condition on multiple therapy. Various chromatographic techniques are frequently used in monitoring concentrations of di- and polyamines in cancer. Among these techniques, thin-layer chromatography and liquid chromatography using pre- or postcolumn derivatization, separating on a reversed-phase or an ion-exchange column are the most commonly used. Besides, high-resolution capillary column gas chromatography (GC) is increasingly used over packed column GC, and in recent years, capillary zone electrophoresis has also gained some importance in polyamine determinations. The review examines the prospects and the limitations of polyamines as cancer markers using chromatographic and electrophoretic techniques.  相似文献   

14.
Members of the phylum Microspora are all obligate intracellular parasites. Little is known concerning metabolic pathways in these parasites, some of which pose serious problems in immunocompromised patients. We investigated polyamine metabolism in the systemic pathogen Enterocytozoon cuniculi using intact pre-emergent spores, and cell-free preparations. We found both polyamine synthetic and interconversion pathways to be operative, as evidenced by conversion of ornithine into polyamines, and production of spermidine from spermine by pre-emergent spores. Recent developments in the antitumour field have highlighted the ability of bis-ethylated polyamine analogues to reduce polyamine levels and block growth of tumour cells. In light of enhanced polyamine uptake in Enc. cuniculi, we have begun to study bis-aryl 3-7-3 and bis-ethyl oligoamine analogues as leads for chemotherapy of microsporidia.  相似文献   

15.
Most of commercially important crops, including maize and common bean, are sensitive to water deficit and salinity. Polyamines are considered to be osmotic and salt tolerance modulators and biochemical indicators of these stresses. In the present study, we measured organ-specific changes in levels of free, microsome- and thylakoid-associated polyamines in leaves and roots of maize and common bean plants exposed for 24 h to osmotic and saline stresses. Putrescine levels were generally higher in the studied organs of both species and under both stresses; only in the roots of salt-treated bean it considerably decreased. In both species, salt stress (200 mM NaCl) induced a significant decrease in free spermidine in roots. We observed a significant decrease in the contents of all polyamines associated with the microsomes isolated from the roots of maize and bean growing in sorbitol and salt conditions. Also the microsomes isolated from the leaves of stressed plants were characterized by the lower contents of polyamines. Our data showed a reduction of putrescine content, with significantly decreased spermidine and spermine levels in thylakoids isolated from the chloroplasts of maize and bean plants growing under both stresses. The results indicate that the studied maize and bean cultivars are rather drought-sensitive. Additionally, microsome- and thylakoid-associated polyamines seem to be good markers of plant stress tolerance.  相似文献   

16.
Objective We investigated serum levels of CA 15-3, sHER2 and CA 125, and their usefulness in the detection of metastatic disease in breast cancer patients.

Methods The levels of CA 15-3, sHER2 and CA 125 tumour markers were determined in 60 patients, 40 with localized and 20 with metastatic breast carcinoma. The control group consisted of 10 healthy women.

Results We found that, at the time of diagnosis, serum levels of all three tumour markers were elevated in patients with distant metastases, but of minute importance in the detection of any breast cancer. When the data for the individual markers were combined the overall sensitivity of metastases detection with all three markers improved. In this regard, 90% of patients with distant metastases had an increase in serum level of at least one of tested tumour markers. Similar results were obtained using receiver operating characteristic curve (ROC). Moreover, using ROC we defined cut-off values for metastasis detection for each of the tested markers.

Conclusion Our findings indicate that measurement of CA 15-3 serum values in conjunction with sHER2 and CA 15-3 can increase sensitivity in metastasis detection.  相似文献   

17.
A search was initiated towards the localization of novel mutated tumour suppressor genes that may be involved in adult leukaemia. For this purpose, we measured the occurrence of loss of heterozygosity (LOH) in nine patients with acute B-lineage leukaemia (ALL) and one with undifferentiated leukaemia (AUL). Eight leukaemias exhibited a diploid karyotype. For each patient, PCR products of 130 polymorphic microsatellite markers, located in subtelomeric areas of every autosomal chromosome arm were analysed to visualize LOH events resulting from reduplication of a single mutated chromosome or from mitotic recombination. These kinds of LOH events contribute most to LOH in model systems but cannot be detected by classical cytogenetic techniques. By comparing allelic PCR products in tumour cells with those in normal cells, LOH was found in tumour cells of one ALL patient at 9p which harbours the known p16INK44 tumour suppressor gene. In the AUL patient, however, LOH was detected at the telomeres of 4q and 21q, suggesting that these sites may contain novel tumour suppressor genes specifically involved in this form of leukaemia. In the DNA of tumour cells from eight out of 10 patients no LOH was detected. This is in contrast with the general assumption that LOH is a frequent phenomenon in ALL. However, some markers at telomeric regions of chromosomes were already homozygous in the control T-cells of several patients. For instance, we found in the DNA of control cells from one patient five consecutive microsatellites on 9p up to 9p43 which were homozygous and in three other patients homozygosity was observed in band 8q24, which includes the MYC gene. These observations indicate that LOH events already are present in non-cancerous putative stem cells and that mitotic recombination may be a very early event in leukaemogenesis.  相似文献   

18.
The polyamines associated to human erythrocytes from healthy donors are mainly localized intracellularly. In fact chromatography of the erythrocytes on a resin which has a high affinity and capacity for polyamines does not affect the amount of polyamines associated to the erythrocytes. The low ability of spermine to adsorb to the external surface of erythrocytes at physiological ionic strength is suggested also by studies conducted with sealed ghosts. Also erythrocytes from patients with hematological and dermatological diseases which contain increased levels of polyamines show an intracellular location of these amines.  相似文献   

19.
Objective We investigated serum levels of CA 15-3, sHER2 and CA 125, and their usefulness in the detection of metastatic disease in breast cancer patients.

Methods The levels of CA 15-3, sHER2 and CA 125 tumour markers were determined in 60 patients, 40 with localized and 20 with metastatic breast carcinoma. The control group consisted of 10 healthy women.

Results We found that, at the time of diagnosis, serum levels of all three tumour markers were elevated in patients with distant metastases, but of minute importance in the detection of any breast cancer. When the data for the individual markers were combined the overall sensitivity of metastases detection with all three markers improved. In this regard, 90% of patients with distant metastases had an increase in serum level of at least one of tested tumour markers. Similar results were obtained using receiver operating characteristic curve (ROC). Moreover, using ROC we defined cut-off values for metastasis detection for each of the tested markers.

Conclusion Our findings indicate that measurement of CA 15-3 serum values in conjunction with sHER2 and CA 15-3 can increase sensitivity in metastasis detection.  相似文献   

20.
Sequential analysis of a few biochemical markers was carried out in rat liver exposed to the hypolipidemic drug, clofibrate. A transformation marker, gamma-glutamyltranspeptidase (GGT), proliferation markers, polyamines, differentiation markers, arginase and ornithine transaminase (OTA), were chosen for the study. GGT activity was significantly reduced with an increase in glutathione concentration. Polyamine synthesis was markedly elevated 5 h following clofibrate administration. However, chronic exposure evoked only a moderate increase in polyamine profile. Hepatic arginase activity decreased significantly during the course of drug treatment. Progressive decrease in OTA, accompanied by hyperornithinemia, suggested decreased catabolism of ornithine. It is felt that these effects of clofibrate on enzyme systems unrelated to its lipid lowering action have far-reaching implications in hepatocarcinogenesis.  相似文献   

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