bluuebunny/crossref_metadata_2025_split huggingface dataset:
Autocrine function of murine F‐MuLV induced myeloblastic cell lines
Authors: Heard J. M. , Fichelson S. , Choppin J. , Varet B. 
Published: February 2007

AbstractFour in vitro permanent suspension cell lines have been established from tumoral organs of myelogenous leukemias developed in mice infected with two biologically cloned Friend helper viruses. Leukemic cells in culture were 100% typical myeloblasts exhibiting a strong myeloperoxidase positivity. A few cells were induced to granulocytic or macrophagic terminal differentiation by post‐endotoxin serum and by various chemical differentiation inducers such as DMSO, N‐butyrate and TPA. We investigated the conditions sustaining the clonal proliferation of these leukemic cells in semi‐solid cultures. Cloning efficiencies were increased by the vicinity of a large number of autologous cells and by the addition of autologous culture supernatant, indicating that the leukemic cells were able to stimulate their own in vitro growth. Cloning efficiencies were also increased by different sources of CSA, such as WEHI‐3B conditioned medium and post‐endotoxin serum. Moreover, the various cell lines stimulated each other through soluble factor(s) secreted in their culture supernatants. Proteins contained in these four culture supernatants were fractionated by successive ammonium sulfate precipitations and ion exchange chromatography. In the four cases the autostimulating activities were eluted in the same fractions as proteins stimulating the normal bone marrow cells colony formation (CSA). These data suggest that the myeloblastic leukemic cell autostimulating factor(s) might be related to the physiological CSA.
Collagenase activity in rabbit carcinoma: Cell source and cell interactions
Authors: Dabbous Mustafa Kh. , El‐Torky Mahmoud , Haney Lena , Brinkley Burchada , Sobhy Nahed 
Published: February 2007

AbstractFibroblast‐like cells (F‐cells) and epithelial‐like (E‐cells) derived from cultures of rabbit VX‐2 carcinoma released collagenase in both active and latent forms in serum‐free medium at a level higher than that of normal rabbit fibroblast cultures. The enhanced capacity of the F‐cells to release the enzyme, however, continued only for a few passages and then decreased significantly to a low level similar to that of the normal fibroblasts. The enzyme‐release by the E‐cells continued for a few more passages at a relatively moderate level, higher than that of normal fibroblasts. The release of collagenase in cultures of F‐cells was enhanced by the presence of E‐cells in mixed cultures as well as by medium conditioned by the E‐cells type. Addition of cytochalasin B at 2 μg/ml did not significantly effect the enzyme activity released in the cultures. Serum from tumor‐bearing rabbits appeared to stimulate the release of enzyme activity in cultures of either cell type.
Natural killer cell activity and spontaneous development of lymphoma. Effects of single and multiple injections of interferon into young and aged C57BL/6 mice
Authors: Bruley‐Rosset Martine , Rappaport Henry 
Published: February 2007

AbstractThe capacity of interferon (IFN) given once or repeatedly to augment natural killer (NK) cell activity in the spleen was tested in young and aged C57BL/6 mice. Multiple injections of 104 u IFN i.p. into 3‐month‐old or 12‐month‐old mice did not augment cytotoxicity mediated by NK cell activity; rather it reduced this activity in relation to the effect obtained with a single injection. When T and B cells or macrophages were removed in vitro, no restoration of NK‐cell activity, and therefore no suppressor cells, could be found in this system. In a long‐term experiment, B6 mice were chronically injected with 104 u of IFN or mock‐IFN from 5 months of age until death. No difference in the modification of NK‐cell activity was observed after IFN and mock‐IFN, regardless of the duration of treatment. However, the capacity of spleen cells to generate cytotoxic T cells after allogeneic stimulation in vitro or in vivo was increased in IFN‐treated mice. The median survival time was improved by 7 weeks through treatment with IFN compared to mock‐IFN, but was reduced by 9 weeks compared to the survival after treatment with saline. No significant difference in the incidence of spontaneous lymphoma resulted from IFN treatment, but the percentage of tumors observed in mice receiving mock‐IFN (68.1%) was higher than that in mice receiving saline (44.1%). These results indicate that, while a stimulating effect resulting in a delay in mortality and in tumor development can be attributed to IFN itself, the contaminating antigenic products are plausibly responsible for the deleterious effect of the total preparation.
Human normal CTL clones: Generation and properties
Authors: Zagury Daniel , Morgan Doris , Lenoir Gilbert , Fouchard Michèle , Feldman Michael 
Published: February 2007

AbstractThis study reports the production of clones of human killer T cells grown in the presence of TCGF4 following sensitization in MLC against (1) allogeneic cells, (2) autologous Bebv+ lymphocytes, or (3) autologous lymphoma cells. Sensitization against the tumor cells required the addition of macrophages. The expression of the cytotoxic activity of the cloned T lymphocytes required re‐stimulation with the specific stimulator cells. The cytotoxic activity seemed to be MHC‐restricted, since (1) cloned allosensitized CTL lysed their corresponding allogeneic targets, but did not lyse autologous Bebv+ cells or K562 cells; (2) cloned CTL sensitized against autologous Bebv+ cells lysed their autologous targets but not allogeneic Bebv+ targets or K562 cells; and (3) cloned CTL sensitized against autologous Burkitt lymphoma cells lysed their corresponding lymphoma targets or autologous Bebv+ targets but did not lyse allogeneic lymphoma cells or Bebv+ cells from the same allogeneic donors. The cloned CTL were homogeneous in expressing the OK T8 molecules and in being negative for T4, T10 or M1. At any given time, 25‐45% of the cloned cells manifested lytic activity. The ultrastructural properties and cell surface OK T markers were different from those of cloned human NK cells. Emphasis is focused on the differences between the structural, functional and culture characteristics of CTL clones produced by direct isolation of MLC responder cells forming conjugates with specific target cells and those of clones from transformed T‐cell lines or from T hybridomas.
The localization of prolactin binding sites in human breast tissue
Authors: Dhadly M. S. , Walker Rosemary A. 
Published: February 2007

AbstractAn immunohistochemical method involving the application of purified human prolactin and a specific antiserum to human prolactin, followed by the peroxidaseanti‐peroxidase immunoperoxidase technique, has been used to detect prolactin binding in benign and malignant human breast tissue. The use of fresh, frozen material has been found to be essential. Prolactin binding has been shown to be a consistent feature of benign breast tissue but a variation within samples has been noted which is irrespective of hyperplastic changes. Fifty six percent of breast carcinomas gave a positive reaction but heterogeneity of binding has been shown to be a significant feature. A relationship between the presence and extent of prolactin binding and good histological differentiation of the tumours has been noted. It is concluded that immunohistochemistry is a suitable method for the demonstration of prolactin binding sites in human breast tissue and can provide useful information with regard to tumour heterogeneity.
A study of glial fibrillary acidic protein (GFAP) in childhood brain tumours
Authors: Marsden H. B. , Kumar S. , Kahn J. , Anderton B. J. 
Published: February 2007

AbstractA retrospective study of 366 primary brain tumours in childhood has been carried out. GFAP was detected in juvenile astrocytoma (76/121), adult astrocytoma (34/78), malignant glioma (0/8), other astrocytic tumours (2/4) and medulloblastoma (0/101). In eight medulloblastomas scanty positive cells were seen but were regarded as reactive rather than neoplastic. The presence of GFAP was only found to be of prognostic value in adult astrocytoma, where its occurrence was associated with a more favourable outcome.
Multiple genes in the H‐2 complex affect differently the number and growth rate of transplacentally induced lung tumours in mice
Authors: Oomen L. C. J. M. , Demant P. , Hart A. A. M. , Emmelot P. 
Published: February 2007

AbstractAlthough several studies have demonstrated that the H‐2 haplotypes influence susceptibility to both spontaneous and carcinogen induced lung tumours in mice, little is known about the nature of their action. In this study, we analysed the effects of four haplotypes (a, h2, h4, b) with a C57BL/IOScSn background on the histological type of the tumours, their incidence, numbers and size. The tumours were studied in 8 and 16 week old progenies of mothers which were injected on the 15th day of pregnancy with N‐ethyl‐N‐nitrosourea. Even with the limited number of haplotypes tested, our data show that the effect of H‐2 genotype is both genetically and biologically complex. Lung tumours of the alveolar type were detected in appreciable numbers only in a and h2 mice, indicating that their incidence is controlled by gene(s) to the left of I‐E. On the other hand, tumours of the papillary type were present in all strains in approximately the same numbers, but their size differed between strains, being largest in a mice, intermediate in h2 and h4 mice, and smallest in b mice. Moreover, in contrast to a, h2 and h4 mice, in b mice the average tumour size did not increase in the time interval between the age of 8 and 16 weeks. Apparently, several MHC genetic factors are responsible for the control of growth and incidence of the transplacentally induced lung tumours. At least one factor maps to the left of I‐E, other(s) to the right of S. It is possible that these genes act through different mechanisms, since they affect the numbers of alveolar tumours, but with papillary tumours their main effect is on their size (growth intensity).
Metastatic clones selected from an RSV‐induced mouse sarcoma share a common marker chromosome
Authors: Di Renzo Maria Flavia , Doneda Luisa , Larizza Lidia , Comoglio Paolo M. 
Published: February 2007

AbstractPrevious work has shown that the metastatic potential of RSV‐transformed fibroblasts is correlated with the ability to form colonies in 0.6% (“hard”) agar. Metastatic subclones were selected by this property from the nonmetastasizing fibrosarcoma B77‐313 line. A marker chromosome was found at high frequency (90% of cells) in all the subclones studied. This marker was detectable in only 0.5% of the parental B77‐3T3 cells, demonstrating that metastatic clone precursors pre‐existed, as a small minority, in the parental line. The genotypic marker appeared to be steadily associated with the metastatic phenotype since, after prolonged in vitro propagation, the subclones retained both the marker chromosome and the high metastatic potential. Although the marker chromosome was constantly present, chromosomal numerical and structural aberrations were also found in 20% of the long‐term‐propagated subclone cells, supporting the suggestion that metastatic properties are associated with cytogenetic instability.
Control of endogenous cell regulators by the second‐stage tumor promoter phorbol‐12‐retinoate 13‐acetate
Authors: Simantov Rabi , Marks Friedrich , Furstenberger Gerhard , Sachs Leo 
Published: February 2007

AbstractThe phorbol esters phorbol 12‐retinoate 13‐acetate (RPA) and 12‐O‐tetradecanoyl phorbol 13‐acetate (TPA) were used to investigate the role of tumor promoters in the control of hormone response in normal and leukemic myeloid celts. RPA and TPA inhibited the binding of [20‐3H]phorbol 12,13‐dibutyrate to the leukemic cells in a competitive manner with 50% inhibition values of 5.2±l.3 and 1.1±0.6 nM, respectively. RPA, like TPA, enhanced (1) prostaglandin E,‐induced cyclic AMP synthesis, (2) the differentiation of leukemic cells induced by the normal myeloid differentiation‐inducing protein, and (3) the formation of normal myeloid cells colonies induced by the normal myeloid growth‐inducing protein. Both compounds can thus control endogenous cell regulators. Since RPA functions in the second stage of tumor promotion in mouse skin, it is suggested that the control of such endogenous regulators may involve biochemical pathways similar to those that are activated in the second stage of tumor promotion.
Interferon‐induced increase in neuraminidase‐releasable sialic acid and glycosphingolipid metabolism in mouse lymphoma and l1210 leukemic cell lines: Correlation with susceptibility to natural killer cell‐mediated lysis
Authors: Yogeeswaran G. , Grönberg A. , Welsh R. M. , Kiessling R. 
Published: February 2007

AbstractChanges in sialoglyoconjugates and glycosphingolipid (GSL)5 metabolism were demonstrated in mouse EL4, P52 and YAC‐1 lymphoma and L1210 leukemia cell lines treated with β‐interferon (IFN). Expression of cell surface (neuraminidase‐releasable) sialic acid on IFN‐treated cells was markedly elevated (three‐ to six‐fold). The increase in neuraminidase‐releasable sialic acid is contributed by sialoglycoproteins and particularly by cell‐surface gangliosides in IFN‐treated cells. Incorporation of [3H]‐galactose into all GSL was elevated in IFN‐treated cells. Thin‐layer chromatographic analysis of GSL of IFN‐treated cells showed an increase in several GSL homologues with striking changes in ganglioside with chromatographic migration of GM2, GM1, and GD1a relative to control cells. IFN‐treated tumor‐cell lines became resistant to lysis by virus‐induced IFN‐activated natural killer (NK) cells, as shown previously, but addition of neuraminidase to IFN‐treated and untreated cells caused only a moderate increase in NK‐sensitivity. This suggests that IFN‐mediated protection of target cells from NK lysis was not due to a preferential masking of target structure by elevated levels of sialic acid. These membrane‐associated changes in GSL and sialic acid in IFN‐treated cells may be potentially significant, because a correlation between certain GSL expression, sialic acid phenotype and susceptibility of target cells to NK‐cell‐mediated lysis have been found in several other systems.
A new tumor promoter, dihydroteleocidin b, enhances cell growth and the production of murine leukemia virus by fibroblasts
Authors: Hoshino H. , Miwa M. , Fujiki H. 
Published: February 2007

AbstractThe effects of tumor promoters on the expression of murine leukemia virus (MuLV) were studied in tissue culture. Dihydroteleocidin B, an indole alkaloid, recently found to be a tumor promoter, enhanced not only the production of Moloney MuLV (M‐MuLV) by a mouse fibroblast cell line, C3H2K, persistently infected with M‐MuLV, but also growth of the C3H2K cells. The production of infectious M‐MuLV by M‐MuLV‐infected C3H2K cells that had been treated with dihydroteleocidin B for 1‐7 days was four or five times higher than that of control cells. C3H2K cells grew faster and became stationary at higher cell densities in the presence of dihydroteleocidin B than in its absence. The tumor‐promoting phorbol esters phorbol‐12, 13‐didecanoate and 12‐O‐tetradecanoylphorbol‐13‐acetate also enhanced the production of M‐MuLY, but their effects were not so strong as that of dihydroteleocidin B. These tumor promoters, however, did not induce production of endogenous MuLV in C3H2K or K‐BALB cells.
High‐density lipoprotein and extracellular matrix promotes growth and plating efficiency of normal human mammary epithelial cells in serum‐free medium
Authors: Biran S. , Horowitz A. T. , Fuks Z. , Vlodavsky I. 
Published: February 2007

AbstractA routine procedure has been developed for the establishment in culture of normal primary and secondary human mammary epithelial cells. The high (80‐100%) rate of success resulted from the combined use of a serumfree medium supplemented with high‐density lipoprotein (HDL) and of cell plating on a naturally produced extracellular matrix (ECM). Plating on ECM greatly improved cell attachment, plating efficiency and initial outgrowth. HDL supported epithelial cell proliferation and prevented their detachment and degeneration while the omission of serum prevented the growth of stromal fibroblasts. Under these conditions we obtained from each specimen, and regardless of the patient's age, pure and actively dividing epithelial cell cultures forming a tightly packed and non‐overlapping cell monolayer covering the entire area of the culture dish. These epithelial cultures could be easily dissociated and subcultured at a split ratio of 1:10. The described procedure will promote studies on the role of hormones and growth factors in the proliferation and differentiation of human mammary epithelial cells and on the susceptibility of human breast epithelial cells to various transforming agents and anti‐cancer treatments.
Inhibition of experimental and spontaneous lung metastases of highly metastatic syrian hamster sarcoma cells by non‐activated bone marrow and peritoneal exudate cells
Authors: Deichman G. I. , Kashkina L. M. , Kluchareva T. E. , Vendrov E. L. , Matveeva V. A. 
Published: February 2007

AbstractThe possibility of inhibiting local tumor growth (experimental and spontaneous lung metastases) of the selected highly‐metastatic Syrian hamster sarcoma of STHE‐LM8 subline by means of non‐activated syngeneic and allogeneic spleen, bone marrow (BMC) and peritoneal exudate (PEC) cells was studied. Retroorbital inoculation of Syrian hamsters with native, or lethally irradiated allogeneic BMC and PEC, but not spleen cells, or hamster embryo cells effectively inhibited the development of experimental and spontaneous lung metastases induced by STHE‐LM8 cells in the animals. Spontaneous lung metastases were effectively inhibited in about 50 % of STHE‐LM8 tumor‐bearing animals (with or without tumor excision) inoculated with BMC five times at 5‐ to 7‐day intervals beginning from 1 ‐10 days after subcutaneous palpable tumor appearance. Experimental lung metastases were inhibited in 20‐80 % of animals inoculated with BMC or PEC once 5‐7 days before the tumor cells, simultaneously with them, or during the 5‐7 days following the inoculation of tumor cells, thus demonstrating that BMC metastasis‐inhibiting activity was expressed during 10‐14 days against single tumor cells, or small clusters of tumor cells, and was not effective at the stage of micro‐, or macrometastasis formation. BMC and PEC of normal allogeneic donors were significantly more active in metastasis inhibition than the same cells of tumor‐bearing animals. BMC of inbred normal Syrian hamsters of the ICV line were significantly less active, or did not inhibit experimental lung metastases either in syngeneic or in randombred allogeneic hamsters, thus apparently demonstrating an unknown genetic defect of their NR system.
Cellular immune response in the blood of cats is restricted to autochthonous feline sarcoma virus‐transformed cells
Authors: McCarty Janet M. , Grant Chris K. 
Published: February 2007

AbstractThe blood‐borne cytotoxic cellular immune response of cats to autochthonous fibroblasts transformed with feline sarcoma virus (FeSV) was examined. Peripheral blood lymphocytes (PBL) from immune animals were assayed for cytotoxic activity using a51Cr release microcytotoxicity assay. The time courses for appearance of cytotoxic cells were similar for all cats: effector lymphocytes appeared in the blood 7 days after immunization; peak activity occurred about day 16, and cytotoxic PBL were no longer detectable by 35 days. The specificity of cytotoxic lymphocytes was studied using autochthonous and allogeneic targets. PBL from each of five immunized cats killed autochthonous transformed fibroblast (ATF) targets, but the immune lymphocytes were not cytotoxic for non‐transformed autochthonous fibroblasts, for allogeneic fibroblasts transformed with FeSV, or for an allogeneic lymphoma cell line which produces feline leukemia virus (FeLV). Specific restriction of target‐cell killing to the ATF occurred at all effector:target‐cell ratios tested, and was maintained throughout prolonged assay incubation periods. The results suggest that for cytotoxicity to occur it is necessary for the immune lymphocytes to recognize a combination of virus‐associated antigens and “self” antigens on the ATF. The similarities between this restricted killing and that caused by cytotoxic T lymphocytes in other mammalian systems are discussed.
Cell‐mediated immune reactivity of sinclair melanoma‐bearing swine to 3 M KC1 extracts of swine and human melanoma
Authors: Hook R. R. , Hamby C. V. , Millikan L. E. , Berkelhammer J. , Stills H. F. , Oxenhandler R. W. 
Published: February 2007

AbstractLeukocyte migration inhibition (LMI) assays were performed using 3 M KCI extracts to detect cell‐mediated immune reactions against tumor‐associated antigens (TAA) of swine melanoma. Positive LMI reactivity was 70% or greater in melanoma‐bearing swine compared to 10% reactivity or less in normal swine tested with extracts of either fresh or tissue‐cultured swine melanoma cells. Positive LMI reactivity was 10% or less in both melanoma and normal swine tested with extracts of normal fetal and adult swine tissues. Extracts of tissue‐cultured swine melanoma and human melanoma cells were equally capable of stimulating positive LMI reactivity in melanoma swine and human melanoma patients; normal swine and human donors demonstrated 10% or less positive LMI reactivity to these extracts. Positive LMI reactivity was not stimulated in swine melanoma or human melanoma donors by extracts of tissue‐cultured human breast tumor cells or fresh and tissue‐cultured mouse B16 melanoma cells. Evaluation of these results indicate that melanoma‐bearing swine develop cell‐mediated immune reactivity toward TAA on swine melanomas and, inasmuch as LMI assays were performed with allogeneic extracts, suggests the presence of common TAA on swine melanomas. Furthermore, these data suggest that swine and human melanoma cells may share some common TAA and that this common TAA is not expressed on mouse B16 melanoma cells.
Spontaneous in vitro malignant transformation in a xeroderma pigmentosum fibroblast line
Authors: Thielmann Heinz Walter , Fischer Elisabeth , Dzarlieva Rule T. , Komittowski Dimitri , Popanda Odilia , Edler Lutz 
Published: February 2007

AbstractThis paper deals with a spontaneous malignant transformation in one of our XP fibroblast lines. This cell line, designated XP29MA, was derived from a 14‐year‐old boy who did not show skin tumors or precancerous alterations either at the time of clinical examination or when the biopsy was taken. We have compared the following features in both the malignant and the benign cell line from which the malignant line developed: tumor formation in nude mice, repair capacity, cytogenetic status, light and electron microscopic characteristics. The benign cell line XP29MA had a doubling time of 4.3 d, did not form tumors in nude mice, showed a very low repair capacity (as determined by colony‐forming ability, unscheduled DNA synthesis and alkaline elution) but exhibited a normal cytogenetic and ultrastructural status. In contrast, the transformed cell line XP29MAmal grew three times faster, formed colonies in methyl cellulose, gave rise to fibrosarcomas in nude mice, showed a drastically higher repair capacity, and was characterized by an extreme genetic imbalance, resulting from numerical and structural chromosome alterations of Nos. 1, 3, 4, 8, 12, 16, 17, 18, 20 and 21. Ultrastructural examination revealed fusiform and polygonal cells, the latter exhibiting large indented nuclei, vesicular dilatations of the endoplasmatic re‐ticulum and numerous lysosomes. The higher repair capacity in XP29MAmal cells is tentatively explained in terms of reversion, enhancement of post‐replication repair and/or expression of SOS‐type functions.