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

The biosynthesis and intracellular distribution of acid mucopolysaccharides in Ehrlich ascites tumor cells was studied in vivo by means of the precursors 35S-sulfate, 3H-glucosamine and 14C-galactosamine. It was found that the acid mucopolysaccharide present in the ascitic fluid supernatant is hyaluronic acid. Hyaluronic acid appears to be of extracellular origin, and it is bound to proteins of the cell membrane. The ascites cells exhibit a very active production of sulfated mucopolysaccharides particularly at the mitochondria and cell membrane level. Chondroitin sulfate A is the major component but also the isomers B and C are present. The possible role of chondroitin sulfate A in the development of neoplastic characteristics of the cell is discussed.
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PMID:In vivo synthesis of acid mucopolysaccharides by Ehrlich ascites tumor cells. 13 92

Heparan sulfate from the surface of a variety of mouse cells at different cell densities was examined by ion-exchange chromatography. The results of this analysis show that: (1) The heparan sulfate from new isolates of Swiss 3T3 cells transformed by SV40 virus (a DNA tumor virus) elutes from DEAE-cellulose at a lower ionic strength than that from the parent cell type. This finding confirms our earlier observation with an established SV40-transformed cell line (Underhill and Keller, '75) and eliminates the possibility that this change is caused by extended passage in culture. (2) For both parent and transformed 3T3 cells, the heparan sulfates from low and high density cultures were the same as judged by chromatography on DEAE-cellulose. This result demonstrates that the transformation-dependent change which we have observed is independent of cell density. (3) The heparan sulfate from Balb/c 3T3 cells transformed with Kirsten murine sarcoma virus (an RNA tumor virus) elutes from DEAE-cellulose prior to that from parent Balb/c 3T3 cells. This result extends the transformation dependent change in heparan sulfate to the Balb/c 3T3 cell line and to cells transformed with an RNA virus.
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PMID:Heparan sulfates of mouse cells. Analysis of parent and transformed 3T3 cell lines. 13 10

Extensive hormonal evaluation was performed in a girl with adrenal carcinoma during the primary tumor stage, following adrenalectomy, during the period when metastases were evident and while on treatment with o,p'-DDD. At the age of 14 months a diagnosis of congenital adrenal hyperplasia was made and treatment with dexamethasone (0.125 to 0.25 mg/day) resulted in a fall-off in growth rate, normal advancement in bone age, decrease in virilization and suppression of 17- ketosteroid excretion which continued until 4 3/12 years of age when virilization increased. At five years of age elevated serum and urinary androgen levels unsuppressible with dexamethasone were noted. Following removal of a large right adrenal carcinoma, serum and urinary hormone levels returned to normal. There months following surgery, liver metastases were documented associated with elevated levels of serum androgens. With o,p'-DDD treatment, serum dehydroepiandrosterone sulfate (DS) and urinary 17-ketosteroid (17-KS) excretion fell rapidly while there was a delay in the fall of free androgens. The persistence of free steroid secretion with decreased formation of DS suggests that the o,p'-DDD may have altered sulfatase activity before causing tumor necrosis and total decrease in steroidogenesis.
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PMID:Virilizing adrenal tumor in a child suppressed with dexamethasone for three years. Effect of o,p'-DDD on serum and urinary androgens. 13 87

Primary liver cancer occasionally presents with feminization. The mechanism is unknown. We studied a young man with primary liver cancer associated with feminization that disappeared after removal of the tumor. Before operation, the serum estrone level was markedly (1113 pg per milliliter) and estradiol and estriol levels were slightly elevated. Human placental lactogen was also increased (0.52 microng per milliliter). Luteinizing hormone, follicle-stimulating hormone and prolactin levels were normal, and testosterone reduced. Beta subunits of human chorionic gonadotropin were not detected in the serum. In vitro assay of tumor tissue showed estrogenic activity and high levels of these subunits. With a reversed isotope dilution technic with crystallization to constant specific activity, we showed the tumor tissue to convert dehydroepiandrosterone sulfate and dehydroepiandrosterone to estrone and estradiol. Production of beta subunits of chorionic gonadotropin and raised serum levels of placental lactogen provided further evidence that the tumor was functioning as trophoblastic tissue.
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PMID:Mechanism of feminization in primary liver cancer. 13 68

By light microscopy the subdermal nodule of a patient with fibrodysplasia ossificans progressiva (FOP) had a fibromatoid histologic appearance. The cytoplasm of the cells stained strongly for mannose-rich glycoprotein with the concanavalin A-horseradish peroxidase (con A-HRP) method. The tumors also exhibited abundant hyaluronidase-digestible mucopolysaccharide in the interstitium with various basic staining reagents. This material appeared to consist principally of hyaluronic acid or chondroitin sulfate with few or mainly masked sulfate esters. At the ultrastructural level, cells interpreted as the tumor cells in the subdermal nodule from the patient displayed extremely hyperplastic granular reticulum and well-developed Golgi elements and appeared very active in synthesis and secretion of protein. The material in the dilated cisternae of the granular reticulum stained for glycoprotein with the con-A-HRP method. Macrophages which comprised the other main cell type in the nodules commonly contacted the tumor cells and occasionally evidenced engulfment of these cells. The intercellular matrix of the nonossified subdermal nodule exhibited greatly increased mucosubstance and, by electron microscopy, showed an unusual network of dialyzed iron-reactive acid muco-substance in the interstitium.
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PMID:Histochemical and ultrastructural studies in fibrodysplasia ossificans progressiva (myositis ossificans progressiva). 14 Dec 14

The mucopolysaccharides were prepared from human lung carcinomas of three histologically different types and the control tissue by exhaustive proteolytic digestion, quaternary ammonium chloride fractionation and column chromatography on Dowex 1 (Cl-). They were identified by chemical, enzymic and electrophoretic methods, as hyaluronic acid (HA), chondroitin sulfate (ChS), dermatan sulfate (DS), heparan sulfate (HS) and over-sulfated ChS and/or DS. Qualitatively they were not differed in tumor and normal tissues. However, the amounts of whole mucopolysaccharide were much increased in carcinomas than those of normal control in order of squamous cell carcinoma greater than small cell undifferentiated carcinoma greater than or equal to adenocarcinoma. The increment of mucopolysaccharide contents in carcinoma are largely due to increased amounts of HA and ChS. Carcinoma-type characteristic pattern was also demonstrated in terms of relative amounts of non-sulfated (HA) and sulfated (ChS, DS, HS) mucopolysaccharides: In squamous cell carcinoma and adenocarcinoma sulfated mucopolysaccharides were predominant (73 to 78% of total mucopolysaccharides), whereas in small cell undifferentiated carcinoma sulfated ones were diminished (25% of total mucopolysaccharides). In normal lung tissue sulfated mucopolysaccharide comprised 64% of total mucopolysaccharides. The presence of over-sulfated ChS and/or DS, which have not until now been found in lung tissue, was higher in carcinoma tissue as compared to the normal control. Total glycopeptides which were derived from tissue glycoproteins and not in detail characterized in this study were decreased in carcinomas of any histological types as compared to those of normal lung tissue, when expressed by hexosamine content. Biological and clinical significance of mucopolysaccharides in carcinoma state was discussed.
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PMID:[Study on mucopolysaccharides in human lung carcinoma tissue--characteristics in histological types (author's transl)]. 16 61

Specific receptor binding of estradiol-17beta (E2) and dihydrotestosterone (DHT) was studied in human myometrial tissue and in human mammary cancer tissue. The inhibition of binding for E2 and DHT by E2, testosterone (T), DHT, dehydroepiandrosterone (DHEA), dehydroepiandrosterone-sulfate (DHEA-S), androstenedione (A) and 5-androstene-3beta, 17beta-diol (Adiol) was tested with the use of dextran-coated charcoal separation of bound and free E2, respectively, and DHT. The percentage of binding inhibition was calculated with reference to the inhibition obtained with nafoxidine in a molar concentration of 1000 for E2 binding, respectively, with cyproterone acetate in a molar concentration ratio of 10,000 for DHT binding. In 15 samples of myometrium tested, receptors were found for both E2 and DHT. From 19 samples of mammary carcinoma tissue 1 was without binding activity, 3 samples bound E2 only, 5 samples DHT only, and 10 showed binding of both. A 50% inhibition of E2 binding in myometrial as well as in tumor tissue, required a molar concentration ratio of 40 for Adiol, of more than 2000 for T and for DHT, and of about 20,000 for DHEA. Significant inhibiting activity for A up to a molar concentration ratio of 10,000 was absent. This was also true for DHEA-S up to 40,000. With regard to DHT binding, Adiol is more active than E2 and less active than T. Thus Adiol was the only substance which exerted a significant inhibiting influence at a molar ratio near physiological range. Adiol might interfere at the receptor level in the estrogenic stimulation of mammary cancer cells.
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PMID:Interaction of delta-5-androstene-3beta, 17beta-diol with estradiol and dihydrotestosterone receptors in human myometrial and mammary cancer tissue. 16 41

[3H]Uridine-labeled Rauscher leukemia virus was used to infect mouse embryo fibroblasts. After the infected cells were separated into nuclear and cytoplasmic fractions nucleic acid was extracted by sodium dodecyl sulfate-phenol-chloroform treatment and analyzed by Cs2SO4 and sucrose density gradient centrifugation. Between 45 and 70 min after infection a transient and synchronized shift of the acid-insoluble radioactive peak toward the RNA-DNA hybrid region occurred in both the nuclear and cytoplasmic fractions. The density of the cytoplasmic hybrid shifted to 1.56 g/ml (RNA equals about 50%), while the sedimentation rate decreased from 36 S to 14 S; however, the density of the nuclear hybrid shifted to 1.58-1.48 g/ml (RNA equals 57-17%, respectively), while its sedimentation rate remained about 65 S. The hybrids in both the nuclear and the cytoplasmic fractions still showed hybrid density after heat denaturation. The processes of the early stages of RNA tumor virus infection are discussed with regard to the functions of viral RNA-dependent DNA polymerase (reverse transcriptase) and a possible integration of viral genetic information into the host chromosome.
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PMID:Fate of viral RNA of murine leukemia virus after infection. 16 22

Mitochondria from a rat mammary tumor (R3230AC) have been compared with mitochondria from pregnant and lactating rat mammary glands, with particular attention paid to inner membrane enzymes and Transport proteins. In the tumor the mitochondrial adenosine triphosphatase was not activated by 2,4-dinitrophenol, in contrast to the mammary mitochondria from lactating or pregnant rats. Translocation of adenosine diphosphate across the inner membrane was found to be more rapid in the tumor by virtue of lovered Km adenosine diphosphate and raised Vmax. Transport of phosphate and dicarboxylic acids occurred at similar rates in all three types of mitochondria. The inner membrane proteins were also examined directly by sodium dodecyl sulfate/polyacrylamide gel electrophoresis and some differences are noted. These results, although they indicate subtle differences between the inner mitochondrial membranes of tumor as compared with those of pregnant or lactating rat mammary glands, cannot form the basis of an explanation for enhanced glucose utilization and aerobic lactic acid production in this tumor.
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PMID:A comparative study of inner membrane enzymes and transport systems in mitochondria from R3230AC mammary tumor and normal rat mammary gland. 16 45

A linked cell-free system has been developed which is capable of transcribing and translating mamalian viral DNA, and its characteristics and requirements are outlined. In this system, simian virus 40 (SV40) DNA Form I (supercoiled) directed the synthesis of discrete polypeptides up to 85,000 daltons in size. One of these products was indistingusihable from authentic major virus capsid protein VPI, as judged by mobility on sodium dodecyl sulfate/polyacrylamide gels, antibody predipitation, and peptide analyses. The cell-free products larger than VPI comprised a number of polypeptides ranging in molecular weight from 50,000 to 85,000. These polypeptides demonstrated no immunological relationship whatsoever to the structural protein VPI. However, two of these products, along with one of approximately 25,000 dlatons, were precipitated with antiserum to SV40 tumor antigen. Linear SV40 DNA generated by the cleavage of Form I DNA with the restriction endonuclease EcoR1 was an efficient template in this system and also directed the synthesis of a polypeptide migrating with VPI on polyacrylamide gels. The potential of this system for defining a functional map of a DNA genome is discussed.
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PMID:Simian virus 40 DNA directs synthesis of authentic viral polypeptides in a linked transcription-translation cell-free system. 16 82


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