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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Several types of tumors contain high concentrations of hyaluronate, yet isolated tumor cells in culture often produce little glycosaminoglycan. To explore the possibility that interactions between tumor cells and host fibroblasts stimulate hyaluronate synthesis, human tumor cells were grown separately from and in coculture with normal human fibroblasts. Stimulation was observed with each of the three types of tumor cells used: LX-1 lung carcinoma, DAN pancreatic carcinoma, and TRIG melanoma. The interaction between LX-1 cells and fibroblasts was studied in detail. Under serum-free conditions, cocultures of LX-1 and fibroblasts synthesized 3-fold more hyaluronate than the sum of that produced by LX-1 and fibroblast cultures grown separately. This stimulation was linear over 72 hr and hyaluronate represented 80% of the glycosaminoglycan synthesized. Maximum stimulation occurred at a ratio of fibroblasts to LX-1 cells of 1-2:1. Quantitation of unlabeled glycosaminoglycans by HPLC analysis of disaccharides generated by digestion with chondroitin ABC and AC lyases (EC 4.2.2.4 and 4.2.2.5) demonstrated that net accumulation of hyaluronate increased 2-fold and that hyaluronate represented 80% of total chondroitinase-sensitive glycosaminoglycan produced by the cocultures. The disaccharide patterns obtained showed that accumulations of chondroitin-4- and chondroitin-6-sulfates were stimulated proportionately to that of hyaluronate in these cocultures. Similar levels of stimulation due to coculture were obtained in serum-containing and serum-free media. Stimulation was not effected by addition of LX-1-conditioned medium to fibroblast cultures or by culturing LX-1 and fibroblasts under conditions where they shared the same medium but were physically separated. Cell contact between LX-1 and fibroblasts thus appears to be necessary for the stimulation of hyaluronate synthesis.
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PMID:Interactions between human tumor cells and fibroblasts stimulate hyaluronate synthesis. 659 27

Using the cholesterol side-chain cleavage enzyme purified from bovine adrenals, we have previously shown that 22-amino-23,24-bisnor-5-cholen-3-beta-ol (22-ABC) and (20R) 20-phenyl-5-pregnene-3 beta, 20 diol (20-PPD) are potent competitive inhibitors of this enzyme. The studies presented herein were designed to characterize the effects of these new inhibitors on steroid production by intact cells. Using cultured Leydig tumor cells, we compared the effects of 22-ABC, 20-PPD, and aminoglutethimide (a well-known inhibitor of the cholesterol side-chain cleavage enzyme) on hormone-stimulated steroidogenesis. Our results show that these compounds inhibit steroid production in a dose-dependent manner and that 20-PPD and 22-ABC are about 100 and 4 times more active, respectively, than aminoglutethimide. In these cells, the inhibitory effects of the new compounds seem to be localized exclusively at the conversion of cholesterol to pregnenolone.
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PMID:Inhibition of steroidogenesis in cultured Leydig tumor cells by 22-amino-23,24-bisnor-5-cholen-3 beta-O1 and (20R) 20-phenyl-5-pregnene-3 beta,20-diol. 668 51

Rat 13762NF mammary adenocarcinoma cell surface glycoproteins from s.c. tumor- or lung metastases-derived cell clones of differing spontaneous metastatic potentials were examined for their relationship to metastasis. After treatment with neuraminidase, lectin-binding assays showed that highly metastatic clone MTLn3 cells express approximately twice the quantity of peanut agglutinin (PNA) binding sites (approximately 2.3 X 10(8) sites/cell) than clones of lower metastatic potential. However, the number of wheat germ agglutinin (WGA)-binding sites on the various cell clones decreased slightly as the metastatic potential of the clones increased. The quantities of concanavalin A (conA)-binding sites were similar (approximately 1.7 X 10(8) sites/cell) in all cell clones and growth conditions. Glycoprotein analysis was performed by electrophoresis on polyacrylamide gels in the presence of sodium dodecyl sulfate (SDS-PAGE) and subsequent staining with 125I-labeled lectins. SDS-PAGE gels stained with 125I-labeled conA revealed mainly one glycoprotein (Mr approximately 150 kD), and the amounts of this glycoprotein did not correlate with metastasis. Differences in WGA-binding glycoproteins were detected between s.c. tumor- and lung metastases-derived cell clones. Several desialylated glycoproteins were detected with 125I-labeled PNA after SDS-PAGE, and the labeling intensity of one (Mr approximately 580 kD) correlated with the metastatic potentials of the various cell clones. This high Mr galactoprotein was further analyzed by [3H]glucosamine metabolic labeling, solubilization, sequential gel filtration, and chondroitinase ABC treatment prior to SDS-PAGE. The 580 kD galactoprotein was expressed in increased amounts on the more highly metastatic clones. Chemical labeling of cell surface sialic acid residues using periodate treatment followed by [3H]borohydride reduction showed an additional change in a major sialoglycoprotein (Mr approximately 80 kD), which decreased in labeling intensity on clones of increasing metastatic potential. The results suggest quantitative changes in cell surface glycoproteins rather than major qualitative alterations are associated with differences in the metastatic behavior of 13762NF tumor cell clones.
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PMID:Cell surface glycoproteins of 13762NF mammary adenocarcinoma clones of differing metastatic potentials. 668 89

A proteoglycan was isolated from ascites fluid produced by a rat yolk sac tumor. The glycosaminoglycan chains of the proteoglycan are all sensitive to digestion with chondroitinase ABC and about 90% are sensitive to chondroitinase AC. The proteoglycan contains 5% protein. Amino acid analysis revealed a high content of serine and glycine which together constitute 37% of the amino acids. Glutamic acid (glutamine) and aspartic acid (asparagine) are also abundant. Galactosamine accounts for 97% of the hexosamine and the remainder is glucosamine. These characteristics indicate that the glycosaminoglycan side chains of this proteoglycan are predominantly chondroitin sulfate with a smaller amount of dermatan sulfate. Antibodies to the proteoglycan were prepared by immunization of a rabbit with purified alkali-treated proteoglycan. Affinity-purified antibodies from the antiserum immunoprecipitated (35S)sulfate-labeled radioactivity from culture media of the yolk sac tumor cells known to contain chondroitin sulfate proteoglycan. This binding was inhibited by the intact purified proteoglycan but not by proteoglycan treated with papain, suggesting dependence of the reactivity of the antibodies on integrity of the protein part of the proteoglycan. Immunofluorescence of the cultured yolk sac tumor cells revealed localization of immune reactive proteoglycans at the cell surface.
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PMID:Isolation of a chondroitin sulfate proteoglycan from a rat yolk sac tumor and immunochemical demonstration of its cell surface localization. 679 88

A transplantable colorectal adenocarcinoma and the normal colonic mucosa derived from rats of ACI/N strain were digested successively with pronase, deoxyribonuclease, chondroitinase ABC, and heparitinase to obtain the corresponding glycopeptide fractions. The amino acid compositions of these two fractions suggested that the polypeptide backbones were quite similar. However, the electrostatic net charges of these fractions were shown to be different by cellulose acetate membrane electrophoresis, ion exchange chromatography, and measurement of sialic acid contents. The glycopeptide fraction derived from adenocarcinoma contained much greater quantities of less acidic glycopeptides than that derived from the normal colonic mucosa. The former exhibited much stronger blood group A and H activities than the latter. Moreover, the former reacted with Ricinus communis lectin I, whereas the latter did not react with this lectin. These results indicate that the carbohydrate structures of tumor sialoglycoproteins are different from those of the corresponding ones in the normal tissue from which the tumor has originated.
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PMID:Sialoglycopeptides obtained from a transplantable rat colorectal adenocarcinoma: a comparison with those from normal colonic mucosa. 688 96

Clinical investigation of 93 patients with histologically confirmed renal pelvic and ureteral cancer were performed. These patients consisted of 55 males and 38 females with a mean age of 64.8 years. There were 61 cases of renal pelvic cancer, 55 cases of ureteral cancer and 23 with cancers of both sites. Thirty-four cases were associated with bladder cancer and 41 of 82 patients had multiple tumors. The overall 5-year survival rate was 46.0%. 5-year survival of stages pTa, pT1, pT2, pT3, and pT4, was 93.3%, 71.8%, 37.5%, 30.4% and 10.5%, respectively. In this report, we evaluated various prognostic factors according to the survival rate. Sex, age, tumor localization, multiplicity, associated bladder cancer and concomitance of CIS had no influence on survival. In the ABC analysis, the B group showed a tendency for a poor prognosis. However it may be explained from the fact that the B group contained more patients at advanced stages than the other groups. Tumor grade, tumor stage, pV factor and pL factor had a significant effect on survivals. But tumor grade, pV and pL factors were closely related to the tumor stage. Thus the stage was thought to be the most important factor in the prognosis of upper urinary tract cancer. Different surgical procedures and irradiation also did not affect the prognosis of the patients with the same degree of invasion. Chemotherapy for all stages had no effect on survivals compared with non-chemotherapeutic group. However only for pT3 and higher stage cases, cisplatin-based chemotherapy improved the prognosis compared with patients not given chemotherapy. In conclusion, chemotherapy containing cisplatin should be considered for treatment of high stage upper urinary tract cancer.
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PMID:[Clinical investigation of renal pelvic and ureteral cancer with special reference to adjuvant chemotherapy]. 747 22

We report herein identification of a novel ligand for CD44, a cell surface glycoprotein implicated in tumor metastasis, lymphocyte differentiation and homing. A mouse T cell line CTLL-2 transfected with cDNA encoding a hemopoietic form of mouse CD44 exhibited a new self-adhesive phenotype, forming large aggregates. The aggregation was blocked by anti-CD44 mAb but little affected by hyaluronidase, indicating the involvement of CD44 and its non-hyaluronate ligand in the cell aggregation. The ability to induce CD44-dependent aggregation was observed in culture supernatants of CTLL-2 and its CD44 transfectants. Immunoprecipitation analysis using a CD44-Ig chimeric molecule indicated that CTLL-2 and its transfectants synthesized a macromolecule (gp600) which bound specifically to CD44. gp600 was readily labeled with radioactive sulfate and treatment of gp600 with chondroitinase ABC or AC II generated a lower molecular weight species (18-22 kDa), suggesting that gp600 consists of a small core protein heavily modified with chondroitin sulfate glycosaminoglycan side chains. However, when binding of CD44 was tested in vitro to chondroitinase-sensitive purified glycosaminoglycans, such as chondroitin-4-sulfate, chondroitin-6-sulfate and dermatan sulfate, no binding was demonstrable, suggesting either that a novel type of chondroitinase-sensitive glycosaminoglycan is recognized by CD44 or that association of the glycosaminoglycan with a core protein is required for recognition by CD44.
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PMID:A novel ligand for CD44 is sulfated proteoglycan. 751 79

Aim of the present study was to investigate the efficacy of 4 different proteolytic treatments (Ficin, Protease type XIV, Microwave irradiation in Citrate buffer and Microwave irradiation in Lead Tiocyanate), compared to the incubation with buffer only, for the detection of cytokeratins in 10 cases of carcinomas from different organs. The same anti-cytokeratin antibody was applied to two sets of tissue sections, after proteolytic treatment, and the reaction was developed by using a different method (ABC or APAAP) for each set of slides. The semiquantitative evaluation of the specimens demonstrated that the higher number of immunoreactive tumor cells was present after Microwave irradiation in Lead Tiocyanate and, to quite a lesser extent, in Citrate buffer. Ficin and Protease type XIV appeared less effective and in some circumstances, the enzymatic digestion of tumor cells seemed to negatively affect the quality of immunostain. When buffer only was used the percentage of immunoreactive tumor cells was considered to be unreliable for diagnostic purposes. The results of the study seem to suggest that proteolytic pretreatment is essential to avoid false negative results when cytokeratin immunostain is essential in histopathology and that Microwave irradiation in Citrate buffer is eligible as the best procedure.
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PMID:Efficacy of different proteolytic treatments for the immunohistochemical stain of cytokeratins. 752 14

We have identified a novel ligand for CD44, a cell surface glycoprotein implicated in tumor metastasis and lymphocyte homing. When the mouse T cell line CTLL-2 was transfected with cDNA encoding a hemopoietic form of mouse CD44, CTLL-2 cells exhibited a new self-adhesive phenotype, forming large aggregates. The aggregation was blocked by neutralizing anti CD44 monoclonal antibody but unaffected by hyaluronidase, indicating the involvement of CD44 and its non-hyaluronate ligand in the cell aggregation. The ability to induce CD44-dependent aggregation was found in culture supernatants of CTLL-2 and its CD44 transfectants. The use of CD44-immunoglobulin chimeric protein revealed that CTLL-2 and its transfectants synthesized a large-molecular weight protein (gp600) which bound specifically to CD44. The gp600 was readily labeled with radioactive sulfate, and treatment of gp600 with chondroitinase ABC or ACII generated a lower molecular weight species (18-22 kDa), suggesting that gp600 consists of a small core protein with chondroitin sulfate glycosaminoglycan side chains. However, binding of CD44 to glycosaminoglycans such as chondroitin 4-sulfate, chondroitin 6-sulfate, and dermatan sulfate was undetectable, suggesting either that a novel chondroitin-type glycosaminoglycan is recognized by CD44 or that a particular configuration of the glycosaminoglycan is required for recognition by CD44.
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PMID:A sulfated proteoglycan as a novel ligand for CD44. 2292 40

Cervico-uterine cancer is the most frequent gynecological neoplasia in Mexico and cervico-vaginal cytology is the most practical and dependable resource in lesions detection. During the last years precursory lesions detection (NIC and HPV infection) has increased. So, every patient presenting with an abnormal cytology should be included in an evaluation program, that includes a colposcopic study with biopsy of suspicious lesions, in order to know cellular abnormality degree, as these studies combination increases diagnosis certainty. Ninety three patients were evaluated by colposcopy, as the Papanicolaou showed abnormality ICN type in any degree or HPV infection data, during the first three years of the Unidad de Colposcopia de la Beneficiencia del Hospital ABC. In 49 patients histopathological study, was done. A correlation of all studies was carried out. There was a correlation cytology-histopathology of 59.18%; and colposcopy-histopathology of 89.79%. It was concluded that evaluation by cytology is insufficient to establish a final diagnosis and treatment, and that colposcopic study is fundamental in the evaluation of the patient with abnormal exfoliative cytology.
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PMID:[Cytologic-colposcopic-histopathologic correlations in preinvasive cervical lesions and cervical Human Papillomavirus infections]. 755 31


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