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1.
Leukemic blast growth factors (LBGFs) are necessary for in vitro growth of clonogenic cells from patients with acute myeloblastic leukemia. As the human bladder carcinoma cell line 5637 had previously been reported to secrete abundant LBGFs into the culture supernatant, the LBGFs in 5637-conditioned medium (5637-CM) were characterized. Measurement of LBGFs was done using an in vitro leukemic blast colony assay in methylcellulose culture. LBGFs in 5637-CM were fractionated by anion exchange chromatography, and two peaks of activity were recovered. Pool B (high-salt eluent) and/or purified granulocyte colony-stimulating factor (G-CSF) were added to the clonogenic leukemic blast cell assays. It was found that pool B was more active than G-CSF in the majority of cases examined and that the two types of activity were synergistic in some cases.  相似文献   

2.
Medium conditioned by the established lung tumor cell line A549 was used as a supplement to culture cells from primary solid lung tumors. Of 36 cases placed into culture, primary cells were obtained in 33 (91.7%). Of 29 cases in which subcultures were attempted, 18 (62.1%) were successful. Nine cell lines have been established by this technique to date. In growth assays, conditioned medium (CM) was found to stimulate both monolayer colony formation and growth in semi-solid medium of cells cultured from primary solid tumors. CM has been found to contain factors with the properties of both transforming growth factor alpha (TGF alpha) and insulin-like growth factor-I (IGF-I). The addition of a combination of these factors as purified peptides to basal medium at levels found in CM (0.1-0.5 ng/ml) stimulated colony formation of lung tumor cells by up to fourfold. These results indicate that secretion of growth factors may be important in tumor growth in vivo, and that use of CM may be a valuable tool for obtaining cultures from primary solid tumors.  相似文献   

3.
The growth of endothelial cells is necessary for angiogenesis, which in turn is required for later steps of tumor progression. In an attempt to purify new modulators of endothelial cell growth from the conditioned medium of human urinary bladder carcinoma cells, we isolated a small and stable oligonucleotide containing 10 to 16 bases. This oligonucleotide inhibited the growth of endothelial cells in vitro and was identified as a fragment of transfer RNA (tRNA). When unfractionated bovine tRNA was added to the cell culture, it specifically inhibited growth of endothelial cells, but not smooth muscle cells, bovine kidney cells, 3T3 fibroblasts, and several cancer cell lines. In contrast, ribosomal RNA, total yeast RNA, and single nucleosides from tRNA hydrolysate had no effect. These results demonstrate a new role for tRNA and its fragment as a selective endothelial cell inhibitor in vitro. J. Cell. Biochem. 76:109–117, 1999. © 1999 Wiley‐Liss, Inc.  相似文献   

4.
The growth of endothelial cells is necessary for angiogenesis, which in turn is required for later steps of tumor progression. In an attempt to purify new modulators of endothelial cell growth from the conditioned medium of human urinary bladder carcinoma cells, we isolated a small and stable oligonucleotide containing 10 to 16 bases. This oligonucleotide inhibited the growth of endothelial cells in vitro and was identified as a fragment of transfer RNA (tRNA). When unfractionated bovine tRNA was added to the cell culture, it specifically inhibited growth of endothelial cells, but not smooth muscle cells, bovine kidney cells, 3T3 fibroblasts, and several cancer cell lines. In contrast, ribosomal RNA, total yeast RNA, and single nucleosides from tRNA hydrolysate had no effect. These results demonstrate a new role for tRNA and its fragment as a selective endothelial cell inhibitor in vitro.  相似文献   

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Erythroid-potentiating activity (EPA) was detected in culture medium conditioned by a human cancer cell line (KONT) that produces colony-stimulating activity (CSA), using erythroid colony formation in vitro. EPA in the medium conditioned by the KONT cells (KONT-CM) was markedly heat stable. After treating KONT-CM at 80 degrees C for 30 min, 30% EPA remained, while CSA was completely inactivated. Both EPA and CSA appeared in approximately the same fractions of the gel filtration, indicating a molecular weight of approximately 30,000 daltons. EPA bound partially to Concanavalin-A Sepharose, whereas CSA almost did not bind. Our results indicate that EPA can be separated from CSA based on heat stability and binding to Concanavalin-A Sepharose.  相似文献   

7.
Previous reports have indicated that metabolic acidosis stimulates H+ excretion, and this excretion is accompanied by an increased turnover of phospholipids (PL) in toad urinary bladder. The purpose of this experiment was to determine if other known stimulators of H+ excretion [insulin, deoxycorticosterone acetate (DOCA), epinephrine, parathyroid hormone, and CO2] might also stimulate PL turnover in the toad urinary bladder. Quarter bladders from normal toads were removed, weighed, and then incubated with [32P]orthophosphate for 2 hr at 25 degrees C. PL were extracted, separated, and detected using thin layer chromatography and autoradiography, and quantitated by liquid scintillation counting. Results were expressed in cpm (100 mg bladder)-1 (hr)-1. One quarter bladder received insulin (100 milliunits/ml), DOCA (10(-6) M), epinephrine (50 mM), parathyroid hormone (100 micrograms/ml), or 5% CO2 during the incubation, whereas the paired quarter bladder received no treatment. Phosphatidylcholine (PC) and phosphatidylinositol turnover were increased by insulin (P less than 0.025 and less than 0.05, respectively). DOCA had no effect on PL turnover, but stimulated the percentage fraction of PC (P less than 0.05) expressed as percentage fraction of total lipids. Five percent CO2 in the bath resulted in an increased rate of turnover of the PL fractions phosphatidylinositol (P less than 0.05), and the phosphatidic acid plus phosphatidyl-serine (P less than 0.01). Epinephrine and parathyroid hormone were both without effect on PL metabolism. We conclude that insulin, DOCA, and CO2 may stimulated H+ excretion in toad bladder in part by increasing turnover of membrane PL, PC, and phosphatidylinositol, and in the case of CO2, phosphatidic acid plus phosphatidylserine as well, but not PC.  相似文献   

8.
Summary Sera from 144 healthy blood donors were screened for the presence of antibody against the bladder carcinoma cell line RT4 by means of an immune adherence assay. Only one serum (9241) demonstrated high activity with a titer of 1/124. Qualitative and quantitative absorption analyses were carried out with a wide variety of cells to characterize the specificity of the reaction. Cells used for absorption were both cultured and non-cultured and normal and malignant. The reactivity was absorbed by the bladder cancer cell lines RT4 and 5637 and the lung cancer cell line SK-LC-LL. In addition, surgically obtained urothelium from a patient with transitional cell carcinoma abrogated reactivity. No other absorbing cells removed the reactivity of serum 9241 for RT4. The antigen defined by this serologic reaction is heat-stable and trypsin-resistant, as demonstrated by using heated or trypsinized RT4 cells for absorption.This study shows that naturally occurring antibody directed toward cell surface antigens of tumor cells is present in some normal individuals. This finding is important in the evaluation of a possible causal relationship between the presence of antibody specific for tumor cell antigens and the development of neoplasia.  相似文献   

9.
Invasion of bacteria into nonphagocytic host cells is an important pathogenicity factor for escaping the host defence system. Gram-positive organisms, for example Staphylococcus aureus and Listeria monocytogenes, are invasive in nonphagocytic cells, and this mechanism is discussed as an important part of the infection process. Uropathogenic Escherichia coli and Staphylococcus saprophyticus can cause acute and recurrent urinary tract infections as well as bloodstream infections. Staphylococcus saprophyticus shows strong adhesion to human urinary bladder carcinoma and Hep2 cells and expresses the 'Microbial Surface Components Recognizing Adhesive Matrix molecule' (MSCRAMM)-protein SdrI with collagen-binding activity. MSCRAMMs are responsible for adhesion and collagen binding in S. aureus and are discussed as an important pathogenicity factor for invasion. To investigate internalization in S. aureus, several fluorescence activated cell sorting (FACS) assays have been described recently. We used a previously described FACS assay, with slight modifications, in addition to an antibiotic protection assay and transmission electron microscopy to show that S. saprophyticus ATCC 15305 and the wild-type strain 7108 were internalized into the human urinary bladder carcinoma cell line 5637. The discovery of the internalization of S. saprophyticus may be an important step for understanding the pathogenicity of recurrent infections caused by this organism.  相似文献   

10.
Two adenocarcinoma cell lines, Breast M25-SF and Breast M, were established from tumor tissue resected surgically from a patient with breast cancer. One, Breast M25-SF, expresses interleukin-2 receptor (IL-2R) on the cell surface and the other, Breast M, does not. The effects of recombinant inteleukin-2 (rIL-2) on the proliferation of these cell lines were investigated. The growth of Breast M25-SF was significantly promoted by rIL-2 ranging from 1,25 U/ml to 640 U/ml. Anti-CD25 (Tac) antibody, significantly blocked the growth enhancement of Breast M25-SF by rIL-2. Breast M, however, did not respond to rIL-2. To confirm more directly the promotion of Breast M25-SF growth by rIL-2, cloning of IL-2 responders from parent Breast M25-SF cells was carried out by limiting dilution without feeder cells in 96-well microplates. No colony formation was found in 24 wells without rIL-2. Eleven, 13 and 6 clones were established from groups of 24 wells containing rIL-2 at 200, 20 and 2 U/ml respectively. All of the clones expressed IL-2R and respond to rIL-2. By using a sensitive polymerase chain reaction technique, we demonstrated that Breast M25-SF but not Breast M expressed IL-2 mRNA, and IL-2 secretion from Breast M25-SF but not Breast M was also confirmed by radioimmunoassay. These findings suggest a role for IL-2 in autocrine support of Breast M25-SF growth. IL-2 may play an important role in the growth control of breast carcinoma cells.  相似文献   

11.
Serum-free culture medium conditioned by an established human pancreatic adenocarcinoma cell line, CAPAN-1, contains copious amounts of immunoreactivity due to pancreatic secretory trypsin inhibitor (PSTI) as demonstrated by radioimmunoassay. The immunoreactive substance was purified from the conditioned medium to apparent homogeneity by trypsin affinity and gel filtration chromatography with an overall recovery of 40%, and its primary structure was determined by Edman degradation. The immunoreactive substance is a peptide of 56 amino acid residues with a calculated molecular weight of 6,241. Its amino acid composition, primary structure, and inhibitory effect against trypsin are indistinguishable from those of human pancreatic juice PSTI, indicating that this substance is PSTI itself. This is the first direct demonstration that tumor cells secrete PSTI in vitro. When CAPAN-1 was inoculated into a nude mouse, it produced a tumor and the tumor synthesized human PSTI in vivo, as demonstrated by the fact that the tumor extract contained 99.0 +/- 26.2 ng of human PSTI/mg of protein, while PSTI was not detected in extracts from other tissues examined. Furthermore, high levels of human PSTI (14.3 +/- 2.6 ng/ml) were detected in the serum of tumor-bearing mice but not in that of nontumor-bearing mice, suggesting that PSTI secreted from the tumor appears in the blood circulation. Taken together, these results strongly support the view that the serum levels of PSTI are elevated in cancer-bearing patients due to secretion of this peptide from tumor cells per se.  相似文献   

12.
A mouse monoclonal antibody, designated 1G3.10, directed against a human urinary bladder cancer cell line TSGH-8301 was generated using the conventional hybridoma technique. It was of the IgG3 subclass with a restricted specificity to bladder cancer and several epithelial cancers, as detected on a panel of various cell lines and tissues by radioimmunoassay and indirect immunofluorescence methods. It also exhibited a strong binding activity to human group A red blood cells, as demonstrated in hemagglutination and absorption tests. Radioimmunoprecipitation and thin-layer chromatography revealed that the antigens recognized by the antibody are a mixture of glycopeptides (M.W. 30, 54, and 108 KD) and glycolipid (retardation factor 0.67-0.83). From a fluorescence activated cell sorter (FACS) study, direct killing of tumor cells by the antibody at a concentration of more than 10 micrograms/ml was observed. This antibody could also mediate both antibody-dependent cellular cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC) in vitro when tested in a 4-hr 51Cr-release test. These results suggest that the monoclonal antibody 1G3.10 may provide an agent for further immunodiagnosis and the treatment of human bladder cancer.  相似文献   

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A human gall bladder carcinoma cell line was established from ascites of a patient of peritonitis carcinomatosa. The pathological diagnosis of this patient was adenocarcinoma tubular ++, moderately differentiated. This cell line was composed of polygonal, spindle and round shaped cells. Each cell types were cloned by single cell cloning technique and each cloned cell secreted CEA or Ferritin or none of them. The doubling time of cell number was 48 hours, and plating efficiency was 14-19%. NOZ cell was transplantable to nude mouse. The morphological feature of transplanted tumor was similar to the original one.  相似文献   

16.
Isolation of a transforming sequence from a human bladder carcinoma cell line   总被引:122,自引:0,他引:122  
C Shih  R A Weinberg 《Cell》1982,29(1):161-169
We have isolated the component of human bladder carcinoma cell DNA that is able to transform mouse fibroblasts. The oncogenic sequence was isolated initially from a lambda phage genomic library made from DNA of a transfected mouse cell carrying the human oncogene. A subcloned insert of 6.6 kb that carried transforming activity was amplified in the plasmid vector pBR322. The subcloned oncogene has been used as a sequence probe in Southern blot analyses. The oncogene appears to derive from sequences present in normal cellular DNA. Structural analysis has failed so far to reveal differences between the oncogene and its normal cellular homolog. The oncogene is unrelated to transforming sequences detected in a variety of other types of human tumor cell lines derived from colonic and lung carcinoma and from neuroblastoma. In contrast, the EJ bladder oncogene appears closely related to one that is active in the human T24 bladder carcinoma cell line. The oncogene appears to have undergone little, if any, amplification in several bladder carcinoma cell lines.  相似文献   

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Because polymorphisms in the methyl group metabolism genes methylene-tetrahydrofolate reductase (MTHFR), methionine synthase (MS), and cystathione beta-synthetase (CBS) affect plasma homocysteine levels and intracellular concentrations of S-adenosylmethionine (SAM), they modify the susceptibility to cardiovascular diseases and cancer. Specifically, genome-wide decreased DNA methylation ('hypomethylation') in human cancers might be a consequence of decreased SAM levels. Because hypomethylation is particularly prevalent in transitional cell carcinoma of the urinary bladder (TCC), the genotype distributions for the two each most prevalent MTHFR, MS, and CBS alleles were compared between 165 TCC patients and 150 population controls. The distributions of the MTHFR 677A/V and the MS 919G/D alleles were not significantly different between cancer patients and controls, even after stratification according to age, gender, tumor stage or grade. The CBS 844INS68 allele was slightly less frequent in TCC patients than in controls (q=0.07 versus 0.10), but was rarer among males in both groups. Among the TCC patients, this gender difference was highly significant (Mantel-Haenszel and chi(2)-test P=0.007). No significant difference between TCC patients and controls was found for any combined genotype. Likewise, the extent of DNA hypomethylation determined in 62 carcinoma specimens was not related to the respective genotypes. Thus, on their own, the MTHFR, MS and CBS genotypes do not appear to act upon susceptibility to TCC or influence the extent of DNA hypomethylation in this cancer.  相似文献   

20.
Measurements of electrical current and oxygen consumption were carried out concurrently under voltage clamp conditions in 11 toad hemibladders. Inhibition of active transport with amiloride then permitted evaluation of the passive conductance and the rate of basal oxygen consumption Jbr, allowing the simultaneous determination of the rates of active sodium transport JaNa and suprabasal oxygen consumption Jsbr-JaNa and Jabr were linear functions of the electrical potential difference over a range of +/- 80 mV. This allowed the comprehensive application of a linear nonequilibrium thermodynamic formalism, leading to the evaluation of the affinity A (negative free energy) of the metabolic reaction driving transport, all phenomenological coefficients, and the degree of coupling q relating transport to metabolism. Values of A determined by two techniques were A1=56.0 +/- 5.8 and A2=58.2 +/- 6.5 kcal per mole. Values of q determined by two techniques agreed well and were less than 1, indicating incompleteness of coupling, and hence lack of fixed stoichiometry between Na transort and O2 consumption. The affinity and the electromotive force of sodium transport ENa are not closely correlated, reflecting the fact that ENa comprises both kinetic and energetic factors.  相似文献   

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