| enhancement of experimental tumors in mice by treatment with concanavalin a. | weanling balb/c mice given injections of 300 micrograms concanavalin a (con a) prior to and at frequent intervals after challenge with moloney murine sarcoma virus (m-musv), 3-methylcholanthrene (mca), or tepc-15 plasmacytoma cells showed an enhancement of tumor induction or development. with the m-musv and mca systems, this enhancement was evidenced by larger tumors and, in the mca system, by more devastating tumors. regression of the m-musv-induced tumors was more prolonged in con a-treated mi ... | 1979 | 480379 |
| prevention of transplantable tumors by adoptive transfer of spleen cells from immunized rats. | fischer 344 rats were specifically hyperimmunized with allogeneic, nonvirus-producing [kirsten murine sarcoma virus (kimsv)] or syngeneic, virus-producing [kimsv (rasheed)] rat tumors. spleen cells taken from these rats adoptively transferred protection against a 100 to 1,000 x rat tumor dose50 cell challenge with several different transplantable rat tumors. protection was obtained with spleen cells after removal of adherent cells and macrophages but not peritoneal cells. the spleen cells were n ... | 1979 | 501086 |
| immunochemical characterization of tumor-associated surface antigens on a moloney leukemia virus-lymphoma, mbl-2. | tumor-associated surface antigens (tasa) on a moloney leukemia virus (m-mulv)-induced lymphoma, mbl-2, in c57bl/6 mice (b6) were characterized. the surface proteins of mbl-2 cells were selectively radioiodinated and then extracted by nonidet p40. the solubilized materials were then reacted with a variety of antisera: monospecific antisera to murine leukemia viral proteins (anti-gp69/71, anti-p30, anti-p15, anti-p12 and anti-p10), sera from b6 which regressed murine sarcoma tumors induced by muri ... | 1979 | 528073 |
| comparative study of different isolates of murine sarcoma virus. | the rna genomes of a variety of murine sarcoma viruses (msv) were compared by heteroduplex analysis. these viruses included the moloney-derived isolates 124-msv, m1-msv, m3-msv, ht1-msv, and np-msv and also two independent isolates, gazdar msv and 1712-msv. all of these viral genomes exhibited the acquired cellular sequences previously identified in 3124-msv and thought to be responsible for transformation and sarcomagenesis. the location of the acquired cellular sequences within the envelope ge ... | 1979 | 229256 |
| heteroduplex analysis of the rna of clone 3 moloney murine sarcoma virus. | heteroduplex analysis of the rna isolated from purified virions of clone 3 moloney murine sarcoma virus (m-msv) hybridized to cdna's from moloney murine leukemia virus (m-mlv) and clone 124 m-msv shows that the main physical component of clone 3 rna is missing all or most of the 1.5-kilobase (kb) clone 124 m-msv specific sequence denoted beta s (s. hu et al. cell 10:469--477, 1977). this sequence is either deleted in clone 3 rna or substituted by a very short (0.3-kilobase) sequence. in other re ... | 1979 | 229257 |
| activity of 10-chloro-5-(2-dimethylaminoethyl)-7h-indolo [2,3-c]-quinolin-6(5h)-one hydrochloride against experimental tumors in mice and rats. | 10-chloro-5-(2-dimethylaminoethyl)-7h-indolo [2,3-c]-quinolin-6(5h)-one hydrochloride (ciq) was shown to exert significant antitumor activity against the ehrlich carcinoma and sarcoma 180 transplantable tumors in mice by the intraperitoneal (ip) or oral (po) routes and when incorporated into diet. a solid tumor induced in balb/c mice by the subcutaneous (sc) implantation of nonproducer murine sarcoma virus-transformed balb/3t3 cells was also inhibited by ciq after ip or po treatment but there wa ... | 1978 | 579626 |
| functional heterogeneity and t cell-dependent activation of macrophages from murine sarcoma virus (msv)-induced tumors. | in studies on the functional activity of macrophages isolated from murine sarcoma virus (msv)-induced tumors, we have found that these cells may suppress immune responses as well as act as effector cells against the tumor. previously, we reported that macrophages from the tumor could inhibit the antitumor response by suppressing proliferation-dependent immune functions. here, we demonstrate that macrophages can also suppress the production of migration inhibition factor (mif) and macrophage acti ... | 1979 | 232622 |
| epithelioid and fibroblastic rat kidney cell clones: epidermal growth factor (egf) receptors and the effect of mouse sarcoma virus transformation. | fibroblastic and epithelioid clones have been isolated from the normal rat kidney line, nrk. these clones were studied for their ability to bind epidermal growth factor (egf), susceptibility to transformation by mouse sarcoma virus (msv), and alteration in egf binding upon sarcoma virus transformation. the epithelioid clones bound much more egf than the fibroblastic clones; scatchard plots on two of these clones, one epithelioid and one fibroblastic, showed that the higher egf binding (1.3 x 10( ... | 1978 | 304450 |
| comparative immunological studies on cryosurgery and surgical operation using moloney murine sarcoma virus-induced primary tumors in balb/c mice. | the effect of cryosurgery and surgical operation on moloney murine sarcoma virus-induced primary tumors in the treated and untreated groups of balb/c mice was compared in terms of tumor growth, cumulative mortality, lymphocyte-mediated cytotoxicity, proliferative response of lymphocytes, and humoral antibody formation. the results indicate that cryosurgical treatment showed both in vivo and in vitro effects; (i) tumor growth and cumulative mortality in mice treated by cryosurgery were significan ... | 1978 | 710802 |
| standardization of the chromium-51 release, cell-mediated cytotoxicity assay: cryopreservation of mouse effector and target cells. | utilizing controlled cryopreservation techniques, we were able to standardize the 51cr release cytotoxicity assay and thereby ensured reliable comparisons between results obtained on different days. optimal conditions for freezing of both effector and target cells were quite similar. dimethyl sulfoxide (dmso) at a concentration of 7.5-10.0% was employed as the cryoprotective agent and cells were frozen at the rate of -1 degrees c/minute. the handling procedures for the cells before and after fre ... | 1977 | 839557 |
| t and b lymphocyte migration into syngeneic tumors. | the migration of splenic t and b lymphocytes into syngeneic tumors undergoing immunologic rejection was investigates. spleen cells were obtained from normal balc/c mice or balb/c mice bearing tumors induced by murine sarcoma virus (msv). either whole spleen cells or immunoabsorbent purified t and b cells were radiolabeled with sodium chromate-51 and injected i.v. into normal or msv inducted-tumor bearing syngeneic recipients. twenty-four hours later the recipient mice were sacrificed and radioac ... | 1977 | 300384 |
| murine sarcoma virus (msv)-induced tumors in mice. i. distribution of msv-immune cytolytic t lymphocytes in vivo. | quantitative studies using a 51cr release assay were performed to analyse the time-course of appearance and specificity of cytolytic cells in c57bl/6 mice inoculated with moloney murine sarcoma virus (msv). various lymphoid organs were studied including spleen, mesenteric lymph nodes (mln), lymph nodes regional to the msv-induced tumor (rln), and peripheral blood. furthermore, the kinetics of appearance of cytolytic cells within the msv-induced tumor was determined. in agreement with previous st ... | 1977 | 300075 |
| protective effect of murine sarcoma virus-superinfected mouse tumor cells against outgrowth of corresponding noninfected tumor. | cultured lines of three newly established methylcholanthrene-induced tumors, mbk and mbl in cba and mc57m in c57bl mice, and two mammary tumors, sbfnhc in cba and s3w in asw mice, were superinfected in vitro with moloney sarcoma or leukemia virus (msv, mlv). after superinfection, they expressed the moloney virus-determined cell surface antigen (mcsa) and murine c-type viral p30 antigen, and produced nb-tropic c-type virus. the virus-infected tumors became more rejectable in normally susceptible ... | 1978 | 705875 |
| phenotypic markers in human skin fibroblasts as possible diagnostic indices of hereditary adenomatosis of the colon and rectum. | hereditary adenomatosis of the colon and rectum (acr) and its gardner's syndrome variant, an autosomal dominant trait, indicate a propensity for neoplasia. the present study describes the growth abnormalities of cultured human skin fibroblasts derived from normal-appearing cutaneous biopsies of acr genotypes and a portion of the clinically asymptomatic acr progeny, first filial generation, and their differential susceptibility to transformation by kirsten murine sarcoma virus. these skin fibrobl ... | 1977 | 922693 |
| a heteroduplex study of the sequence relationships between the rnas of m-msv and m-mlv. | the regions of sequence homology between the rna genomes of a murine sarcoma virus (clone 124 moloney-msv) and its parental helper virus (clone 3 moloney-murine leukemia virus (m-mlv)) have been mapped. long complementary dna transcripts of the m-mlv rna were hybridized to m-msv rna, and the structures of the hybrids were observed in the electron microscope. beginning at the 5' end, the two rnas are homologous for a region of length 2.25 kb (kilobases). in the next region, of length approximatel ... | 1977 | 844103 |
| reduced transplantability of syngenic mouse tumors superinfected with membrane viruses in nu/nu mice. | transplantability of mouse tumors superinfected with various kinds of membrane viruses was investigated in syngeneic hosts. methylcholanthrene-induced fibrosarcomas in balb/c mice, meth a, and in c57bl/6 mice, bmt-, superinfected with friend lymphatic leukemia virus in mice given neonatal injection of the virus, grew more slowly than uninfected tumors. the retardation of growths was not observed in mice that had been given injections of the virus at birth. similarly, meth a and a hepatoma in c3h ... | 1976 | 1006777 |
| in vitro studies of cell-mediated immunity to moloney murine leukemia virus and moloney leukemia-associated surface antigens. | cell-mediated immunity to moloney murine leukemia virus (m-mulv) and to tumor-associated surface antigens of leukemia cells induced by the virus was studied with an in vitro migration inhibition factor assay. spleen cells of c57bl/6n mice at day 14 following inoculation with moloney murine sarcoma virus, produced migration inhibition factor in response to m-mulv. the moloney murine sarcoma virus-immune spleen cells, however, did not respond to other murine type c viruses, to akr and rauscher vir ... | 1979 | 387218 |
| search for nucleic acid sequences complementary to a murine oncornaviral genome in poly(a)-rich rna of human leukemic cells. | the presence of viral-like sequences in the rna of various types of leukemic cells was investigated by hybridizing cellular poly(a)-containing rna with cdna synthesized in an endogenous system of purified moloney murine sarcoma virus [m-msv-(mlv)]. poly(a)-rna-cdna hybrids were detected by assaying their resistance to s1 nuclease. hybrids were found in 22 out of the 46 leukemias that were tested. none of the controls, including material obtained from buffy coats, bone marrow cells, and a continu ... | 1975 | 1061078 |
| virus-induced osteosarcoma in rats. | an experimental model for osteosarcoma was developed in which, after moloney murine sarcoma virus was injected into the tibial marrow space of three strains of inbred neonatal rats, a highly malignant neoplasm arose within ten days. this tumor was readily maintained in tissue culture and was transplantable to adult rats. it arose in the metaphyseal marrow of several bones, was locally invasive, metastasized to the lungs, and histologically resembled osteosarcoma. | 1976 | 1063127 |
| immunogenicity of virus-induced rat osteosarcoma. | the immunogenicity of a virus-induced rat osteosarcoma was studied utilizing the lymphocyte microcytotoxicity test. intratibial injection of murine sarcoma virus (moloney) resulted in the development of palpable tumors at the injection site which on histopathological examination appeared to be osteosarcomas. in 73 per cent of animals injected these tumors progressed and metastasized to the lungs. lymphocytes from these "progressor" animals demonstrated an ability to kill osteosarcoma cells in vi ... | 1976 | 1063128 |
| augmentation of natural cytotoxic reactivity of mouse lymphoid cells against syngeneic and allogeneic target cells. | the levels of natural cell-mediated cytotoxicity against tumor cells in young balb/c and balb/c nude mice could be augmented by inoculation of a variety of mouse tumor cells or of mouse thymocytes. in older mice with low levels of spontaneous cytotoxic reactivity, inoculation of tumor cells led to rapid appearance of cytotoxicity. this augmented cytotoxicity reached a peak 3 days after inoculation and then declined rapidly. the specificity of the augmented cytotoxicity appeared to be the same as ... | 1977 | 844921 |
| suppression of moloney sarcoma virus immunity following sensitization with attenuated virus. | murine sarcoma virus (moloney strain) (msv-m)-induced tumors are unusual in that they regularly appear less than 2 weeks after virus inoculation, progress for 1 to 2 weeks, and are rejected by normal adult balb/c mice. rejectio leaves the animals immune to tumor induction. in the present study, presensitization of normal adult balb/c mice with attenuated msv-m resulted in an altered pattern of tumor immunity. injection of active msv-m into the presensitized animals resulted in tumor induction an ... | 1976 | 1000500 |
| defective friend spleen focus-forming virus: interfering properties and isolation free from standard leukemia-inducing helper virus. | defective friend spleen focus-forming virus (sffv) is able to interfere with the ability of its naturally occurring leukemia-inducing helper virus (llv-f) to induce xc plaque formation in several different strains of mouse embryo cells. this interference has been observed by using two different sffv preparations, one contained in an nb-tropic stock of friend virus (fv) complex, and the second present in a c57bl-adapted strain of fv complex containing an associated b-tropic llv-f helper. the llv- ... | 1977 | 904028 |
| studies on the distribution and origin of cytolytic t lymphocytes present in mice bearing moloney murine sarcoma virus (msv)-induced tumors. | | 1975 | 1085620 |
| anti-viral activity induced by culturing lymphocytes with tumor-derived or virus-transformed cells. identification of the anti-viral activity as interferon and characterization of the human effector lymphocyte subpopulation. | a viral inhibitor(s) is released in the supernate of mixed cultures containing human or mouse lymphocytes and cells from certain lines. the inhibitor is active against a variety of unrelated viruses and is a protein that is not toxic for cells. it does not inactivate viruses directly, but inhibits viral replication through an intracellular mechanism that involves synthesis by the cells of both rna and protein. these characteristics identify the inhibitor as an interferon. the anti-viral activity ... | 1978 | 650155 |
| in situ fc receptor-bearing cells in two murine tumors. i. isolation and identification. | the in situ inflammatory response was studied in 2 different tumors, the t1699 mammary adenocarcinoma in inbred dba/2 mice and a sarcoma induced in inbred c57bl/6 mice by murine sarcoma virus. the presence of fc receptors (fcr's) on infiltrating host cells was determined by rosette formation with antibody-coated sheep red blood cells (ea). differences in fcr-binding activity among various cells were detected with the use of ea prepared with a range of antibody concentrations. cells bearing fcr r ... | 1978 | 650702 |
| effects of hydroxyurea on murine type c virus-specific dna synthesis in newly infected cells. | cell transformation and replication of the rauscher pseudotype of moloney murine sarcoma virus in mouse embryo fibroblasts were inhibited by hydroxyurea within a critical time period of 30 to 90 min postinfection. in cells infected by rauscher leukemia virus, treatment with 1mm hydroxyurea during the critical time period resulted in the accumulation of minus-strand dna (molecular weight, 3 x 10(6)) in association with the parental viral genoma rna. this 5 to 6 x 10(6) dalton rna:dna hybrid was f ... | 1978 | 657143 |
| [histopathologic and ultrastructural study of tumors induced by murine sarcoma virus (msv) (author's transl)]. | various growth phases of moloney murine sarcoma virus (m-msv) induced tumors in suckling and young adult balb/c mice have been studied by light and electron microscopy. in the early phase (3-6 days following m-msv), observations at the injection site of the thigh muscles consisted of endo- and perimysial edema "activated" muscle satellite, cells, endothelial cells and fibroblasts, scattered type c virus particles within the muscle fibers, muscle fibers and endomysial cells undergoing necrosis an ... | 1975 | 1226574 |
| the transforming gene of moloney murine sarcoma virus. | a cleavage map of the moloney murine sarcoma viral dna was constructed and compared with that of a spontaneously occurring deletion mutant. by restriction enzyme analysis, it was shown that a region encompassing over 40% of the viral information was not essential for transformation or rescue of the deletion mutant. the transforming region was further localised by analysis of the transforming activity in tissue culture of isolated restriction fragments of linear duoble-stranded sarcoma viral dna. ... | 1979 | 503218 |
| inhibition of cell-mediated cytotoxicity against tumor-associated antigens by suppressor cells from tumor-bearing mice. | spleen cells from mice bearing primary tumours induced by moloney strain of murine sarcoma virus (m-musv) strongly inhibited the in vitro generation of specific secondary cell-mediated cytotoxic response of spleen cells from m-musv regressor mice. these suppressor cells were resistant to treatment with anti-theta serum and complement or to x-irradiation. it appeared that suppressor cells may have had a role in limiting the host's immune response against tumor growth. | 1976 | 1255803 |
| tumor induction by moloney sarcoma virus in athymic nude mice. | athymic nude (nu/nu) mice, normal nmri (plus/plus) mice, and nu/plus heterozygotes, inoculated at birth with the moloney strain of murine sarcoma virus (m-msv), did not differ either in tumor growth rate or incidence or in mortality due to tumor development; neither did nude (nu/nu) and normal nmri mice inoculated with m-msv at 30 days of age differ in the initial tumor growth rate. however, tumors induced in adult nude mice grew progressively and eventually killed the hosts, whereas tumors indu ... | 1975 | 1078700 |
| two functionally distinct anti-tumor effector cells isolated from primary murine sarcoma virus-induced tumors. | the ability of cells from primary msv-induced tumors to function as effector cells in vitro was evaluated. host cells were isolated by enzymatic disaggregation of the tumor and fractionated by sedimentation velocity at unit gravity on a ficoll gradient. characterization of these cells indicated that 30 to 40 % were t lymphocytes, about 50% were macrophages and less than 5% were b lymphocytes. two different functional activities were mediated by these cells: cytolysis, as measured by the cra, and ... | 1976 | 1084897 |
| elimination of the sarcoma genome from murine sarcoma virus transformed cat cells. | cat cells transformed by moloney murine sarcoma virus contain virus-specific sequences in their rna and dna. cloned, spontaneous revertant cell lines derived from clones of these cells had no evidence of the sarcoma genome in the cell rna or dna as judged by rna-complementary dna or dna-complementary dna hybridizations. ?this is apparently the first report of loss of a transforming genome in a revertant cell line. | 1976 | 1257745 |
| mixed lymphocyte/tumor-cell interaction in a murine sarcoma virus (moloney)-induced tumor system. comparison between lymphoproliferation and lymphocyte cytotoxicity. | studies of the mlti were performed in a primary msv-induced tumor system. reactivity against mitomycin-c-treated rbl-5 cells could be detected during a limited period at about 14 days after virus injection. the degree of reactivity of msv 14 spleen cells was quite variable; stimulation indices ranged from 2.2 to 9.4. activity in the mlti appeared to a great extent to be dependent on t-lymphocytes. a relatively broad spectrum of specificity was demonstrated in experiments using additional stimula ... | 1976 | 1254360 |
| v-mos proteins encoded by myeloproliferative sarcoma virus and its ts159 mutant. | the myeloproliferative sarcoma virus (mpsv) v-mos protein was predicted to be identical in size to p39c-mos because of an observed one-base deletion in the seventh codon of the env-mos open reading frame, which would allow translation to initiate at the methionine equivalent to codon 32 of the env-mos gene. on the basis of published results, p39c-mos is known to have greatly reduced in vitro protein kinase activity compared with p37env-mos encoded by moloney murine sarcoma virus. unexpectedly, t ... | 1992 | 1309903 |
| expression of gene-specific rna in cultured cells exposed to rotating 60-hz magnetic fields. | replicate sets of cultures of mouse and of human cells were exposed to cyclic, sine wave, 60-hz rotating magnetic fields of 1.0 gs (1 gs [symbol: see text] 0.1 mt) for 24-, 48-, or 72-h periods. total rna extracted from unexposed control and from magnetic field exposed cells was dot blot hybridized to a number of oncogene probes (including v-myc, v-fos, v-raf, and v-ha-ras), a probe for 3611 murine sarcoma virus, a probe for the 70,000 dalton heat shock protein (hsp70), and a probe for the long ... | 1992 | 1325160 |
| expression and characterization of recombinant human protein s in heterologous cells--studies of the interaction of amino acid residues leu-608 to glu-612 with human c4b-binding protein. | mouse c127 epithelioid cells were genetically engineered to produce biologically active gamma-carboxylated human protein s. a full length human protein s cdna was cloned into a bovine papilloma virus (bpv) based shuttle vector under the transcriptional control of the moloney murine sarcoma virus enhancer and the mouse metallothionein promoter. stable expression was obtained in transfected c127 cells. expression of gamma-carboxylated protein s was dependent on the presence of vitamin k in the cul ... | 1992 | 1325680 |
| malignant transformation and viral replication of rat bone and muscle cells after in vitro infection with rat-adapted murine sarcoma virus (moloney). | isolated bone and muscle cells from rat fetuses were infected with the rat-adapted osteosarcomogenic murine sarcoma virus (moloney) for examination of malignant transformation and viral replication. after the infection, the bone cells underwent an unusual transformation characterized by two patients in the focus formation. in the early transformation (transformation i), foci consisting of only morphologically altered cells appeared, but they soon disappeared. focus formation of this type continu ... | 1976 | 975041 |
| pheochromocytomas and c-cell thyroid neoplasms in transgenic c-mos mice: a model for the human multiple endocrine neoplasia type 2 syndrome. | transgenic mice carrying and expressing a mos protooncogene, linked to the moloney murine sarcoma virus long terminal repeat, develop severe neurological defects and lens abnormalities. here we report that after long latent periods, mice in three of four of these mos transgenic lines develop a high frequency of multicentric pheochromocytomas and/or medullary thyroid neoplasms. the pattern of tumor formation is remarkably similar to the human autosomal dominantly inherited neoplastic syndrome, mu ... | 1992 | 1345812 |
| on the early emergence of reverse transcription: theoretical basis and experimental evidence. | reverse transcriptase (rt) was first discovered as an essential catalyst in the biological cycle of retroviruses. however, in the past years evidence has accumulated showing that rts are involved in a surprisingly large number of rna-mediated transpositional events that include both viral and nonviral genetic entities. although it is probable that some rt-bearing genetic elements like the different types of aids viruses and the mammalian line family have arisen in recent geological times, the po ... | 1992 | 1282161 |
| molecular cloning and characterization of v-mos-activated transformation-associated proteins. | using monoclonal antibodies we previously detected two forms of transformation-associated proteins, a 64-kda protein and a 68-kda protein, in temperature-sensitive 110-moloney murine sarcoma virus-mutant-transformed rat kidney 6m2 cells. the identity and functions of the transformation-associated proteins were previously unknown. by molecular cloning techniques and immunoscreening, we have isolated two cdna clones (34a and 79b3) that were found by western blot analysis to code for a monoclonal a ... | 1992 | 1370458 |
| midline brain tumors in msv-sv 40-transgenic mice originate from the pineal organ. | adult transgenic mice expressing the large t-antigen of the simian virus 40 (sv 40) under the control of the moloney murine sarcoma virus (msv) enhancer and the sv 40 promoter develop inheritable uniform midline brain neoplasms showing features of primitive neuroectodermal tumors. the origin and histogenesis of these tumors were investigated in the present study. the brain and pineal organ of fetal and young transgenic mice less than 3 months old displayed normal macroscopic and microscopic feat ... | 1992 | 1373025 |
| mechanism of anti-human immunodeficiency virus action of polyoxometalates, a class of broad-spectrum antiviral agents. | various polyoxometalates proved inhibitory to the replication of a number of enveloped dna and rna viruses, i.e., herpesviruses (herpes simplex and cytomegalo), togaviruses (sindbis), paramyxoviruses (respiratory syncytial), rhabdoviruses (vesicular stomatitis), arenaviruses (junin and tacaribe), and retroviruses [human immunodeficiency virus type 1 (hiv-1) and type 2 (hiv-2), simian immunodeficiency virus, and murine sarcoma virus]. the most potent compounds, i.e., jm1590 [k13[ce(siw11o39)2]. 2 ... | 1992 | 1282664 |
| in vitro differentiation of the human osteosarcoma cell lines, hos and khos. | the osteogenic potential of the two human osteosarcoma cell lines hos and khos; a cell line produced by the transformation of the hos cells by the kirsten murine sarcoma virus, was studied in vitro. hos cells cultured more than 2 weeks formed nodules composed of two morphologically distinct layers, an epithelial-like surface cell layer and a collagen-rich inner cell layer. alkaline phosphatase (alpase) activity occurred in the plasma membrane of the surface cell layer, and calcified substances d ... | 1992 | 1357821 |
| genomic structure and expression of the human fau gene: encoding the ribosomal protein s30 fused to a ubiquitin-like protein. | the fau gene is the cellular homolog of the fox sequence in the finkel-biskis-reilly murine sarcoma virus (fbr-musv). this virus acquired the fau sequence in its reversed transcriptional orientation. human and mouse fau cdna's were identified and both encode a new protein of 133 aa. we show that fau (for fbr-musv associated ubiquitiously expressed gene) becomes expressed in all different tissues tested as a 600 bp messenger and we report the genomic structure of the human fau gene. the gene cons ... | 1992 | 1326960 |
| antibody-dependent lymphocyte cytotoxicity in the murine sarcoma virus system: activity of igm and igg with specificity for mlv determined antigen(s). | antisera with specificity for moloney leukemia virus-(mlv) determined antigen(s) were studied for their ability to induce mlv antigen bearing target cell reduction by lymphocytes in microcytotoxicity assays. sera from animals which had regressed moloney sarcoma virus (msv) tumors as well as sera from animals with progressively growing msv tumors were found to induce normal lymphocytes to be active against the targets. regressor serum was found also to induce cytotoxicity by immune lymphocytes fr ... | 1975 | 1117138 |
| cell-mediated immunity to moloney sarcoma virus in mice. ii. analysis of antigenic specificities involved in t lymphocyte-mediated in vivo rejection of murine sarcoma virus-induced tumors. | sublethally irradiated balb/c mice innoculated with moloney sarcoma virus (msvm) develop progressively growing tumors and die within 30 days of virus innoculation. these animals can be protected from tumor progression (and death) by innoculation of small numbers of msv-immune t lymphocytes from msv-m innoculated (but unirradiated) animals. t lymphocytes in these donor animals have been shown to express immunity to a variety of viral and virally-induced antigens. we have investigated whether immu ... | 1975 | 1086221 |
| substrate preference of metalloproteinases secreted by ts-110 moloney murine sarcoma virus-transformed normal rat kidney cells. | in this study, the two forms of affinity-purified transformation-associated proteins (taps) (68 and 64 kd) were shown to have different substrate preferences. for the 68-kd tap, the order of substrate preference was collagen types i, iii, and v; fibronectin; gelatin; and collagen iv. for the 64-kd tap, the order of substrate preference was collagen i, iii, and v and gelatin. the 64-kd tap did not cleave collagen iv and fibronectin. we also found a 71-kd metalloproteinase in the concentrated puri ... | 1992 | 1449476 |
| characterization of activated and normal mouse mos gene in murine 3t3 cells. | we have characterized the mouse mos proto-oncogene product, pp39mos, in murine fibroblasts. when expressed in nih3t3 cells under the influence of the long terminal repeat regulatory element from moloney murine sarcoma virus [nih(pts-1) cells], the mos protein was present in low levels and had a half-life of about 30 min. in extracts from nih(pts-1) cells, we detected additional forms of mos protein that apparently arose from internal initiation codons (p24mos and p29mos) or from upstream non-aug ... | 1992 | 1461652 |
| [adducts of 3'-azido-2,3'-dideoxythymidine 5'-phosphate or 5'-phosphonate as inhibitors of cytopathic effect and transformation of cells under the influence of retroviruses in cell culture]. | inhibition of hiv-1- or hiv-2-induced cytopathicity and (moloney) murine sarcoma virus (msv)-induced cell transformation by amino acid and amino alcohol adducts of either 3'-azido-2',3'-dideoxythymidine 5'-monophosphate (aztmp) or 5'-hydrogenphosphonate (azthp) were investigated. both types of nucleotide adducts inhibited replication of hiv-1 and hiv-2 in mt-4 cells at a 1.5- to 3-fold higher ec50 (50% effective concentration) than azt; and, also, selectivity indexes of these adducts were approx ... | 1992 | 1470177 |
| moloney murine sarcoma virus musvts110 dna: cloning, nucleotide sequence, and gene expression. | we have cloned moloney murine sarcoma virus (musv) musvts110 dna by assembly of polymerase chain reaction (pcr)-amplified segments of integrated viral dna from infected nrk cells (6m2 cells) and determined its complete sequence. previously, by direct sequencing of musvts110 rna transcribed in 6m2 cells, we established that the thermosensitive rna splicing phenotype uniquely characteristic of musvts110 results from a deletion of 1,487 nucleotides of progenitor musv-124 sequences. as anticipated, ... | 1992 | 1501276 |
| [2',5'-bis-o-(tert-butyldimethylsilyl)]-3'-spiro-5''-(4''-amino-1'',2''-oxathiole-2'',2''-dioxide) (tsao) derivatives of purine and pyrimidinenucleosides as potent and selective inhibitors of human immunodeficiency virus type 1. | the [2',5'-bis-o-(tert-butyldimethylsilyl)]-3'-spiro-5''-(4''-amino- 1'',2''-oxathiole-2'',2''-dioxide) (tsao) derivatives of ribofuranosylthymine, uridine, 5-bromouridine, 5-methylcytidine, inosine, and adenosine are potent and selective inhibitors of human immunodeficiency virus type 1 (hiv-1) but not of other retroviruses (hiv-2, simian immunodeficiency virus, or moloney murine sarcoma virus). the 50% effective concentration (ec50) of the most active tsao congeners for inhibition of hiv-1 rep ... | 1992 | 1510396 |
| suppression of transformed phenotype in hybrids of v-fgr and v-raf transformed rat-1 cells with rat embryonic fibroblasts is due to transcriptional inactivation of viral oncogenes. | rat-1 cells that had been transformed to tumorigenicity by transfection with the retroviral oncogenes v-raf from 3611-murine sarcoma virus, or v-fgr from gardner-rasheed feline sarcoma virus were fused with rat embryonic fibroblasts at an early passage. in both fusion experiments hybrid cells were isolated that exhibited normal morphology, anchorage requirement for proliferation, and either no tumorigenicity (v-fgr) or extended latency periods for tumor growth (v-raf) in nude mice. transcription ... | 1992 | 1563491 |
| expression of a 91-kilodalton pea3-binding protein is down-regulated during differentiation of f9 embryonal carcinoma cells. | proteins binding to the pea3 enhancer motif (aggaag) activate the polyomavirus early promoter and help comprise the viral late mrna initiator element (w. yoo, m. e. martin, and w. r. folk, j. virol. 65:5391-5400, 1991). because many developmentally regulated cellular genes have pea3 motifs near their promoter sequences, and because ets family gene products activate the pea3 motif, we have studied the expression of pea3-binding proteins and ets-related proteins during differentiation of f9 embryo ... | 1992 | 1569949 |
| human smooth muscle myosin light chain-2 gene expression is repressed in ras transformed fibroblast cells. | we have previously characterized human smooth muscle myosin light chain (mlc)-2 isoform by complementary dna cloning and have shown that this isoform is expressed in a number of nonmuscle cells such as fibroblast cells. in this report, we show that when human osteosarcoma derived clonal cells (te 85 clone f-5) (hos), which are immortalized and nontumorigenic, undergo transformation following infection by kirsten murine sarcoma virus (k-hos) or by a chemical carcinogen [n-methyl-n-nitro-n-nitroso ... | 1992 | 1599878 |
| overproduction of metalloproteinases by v-mos-transformed rat kidney (6m2) cells. | using monoclonal antibodies, we previously detected two forms of transformation-associated proteins (taps), p64 and p68, in the rat kidney (6m2) cells transformed by the temperature-sensitive 110-murine sarcoma virus-moloney-mutant. taps were secreted as glycoproteins by 6m2 cells grown at 33 degrees c, but not by 6m2 cells grown at 39 degrees c. the identity and functions of taps were previously unknown. by molecular cloning techniques and immunoscreening, we have isolated two different cdna cl ... | 1992 | 1602817 |
| sodium butyrate selectively induces transcription of promoters adjacent to the momsv viral enhancer. | the long terminal repeat region of the moloney murine sarcoma virus (momsv) was cloned upstream from the chinese hamster ovary adenine phosphoribosyltransferase (aprt)-encoding gene (aprt) in order to enhance synthesis of the aprt protein. the replacement of the native promoter with the viral enhancer-promoter increased the enzymatic activity of aprt two- to threefold. addition of sodium butyrate (nabu) to the cell growth medium induced aprt activity ten- to 20-fold above wild-type levels in bot ... | 1992 | 1634113 |
| nucleotide sequence and tissue distribution of mouse transforming growth factor-alpha. | transforming growth factor-alpha (tgf alpha) is secreted into the medium of the moloney murine sarcoma virus-transformed 3t3 cell line, 3b11-1c. using reverse transcription-polymerase chain reaction (rt-pcr), we have amplified, cloned and sequenced a cdna fragment from this cell line which encodes the full protein-coding region of the mouse tgf alpha precursor. the deduced amino acid sequence (159 residues) differs from that of human tgf alpha at 13 sites and from that of rat at 3 sites. in the ... | 1992 | 1420315 |
| transcriptional activation through ets domain binding sites in the cytochrome c oxidase subunit iv gene. | a mutational analysis of the rat cytochrome c oxidase subunit iv (rco4) promoter region revealed the presence of a major control element consisting of a tandemly repeated pair of binding sites for a nuclear factor from hela cells. this factor was designated nrf-2 (nuclear respiratory factor 2) because a functional recognition site was also found in the human atp synthase beta-subunit gene. deletion or site-directed point mutations of the nrf-2 binding sites in the rco4 promoter resulted in subst ... | 1991 | 1656236 |
| delayed tumour appearance and absence of regression in nude mice infected with murine sarcoma virus. | | 1975 | 1110765 |
| murine sarcoma virus related nucleic acid sequences in a non-transforming virus derived from an interspecies pseudotype sarcoma virus. | a number of sarcomagenic viruses recovered from hamster tumors induced originally by moloney sarcoma virus or several of its mouse pseudotypes appear to be interspecies pseudotypes with structural proteins of hamster type-c viruses and nucleic acid sequences of both mouse and hamster specificity. a non-transforming virus (gloh-minus) recovered from a sarcomagenic virus preparation obtained from a tumor induced by the gross pseudotype of moloney sarcoma virus was previously shown to retain mouse ... | 1975 | 1140876 |
| 2',5'-bis-o-(tert-butyldimethylsilyl)-3'-spiro-5''-(4''-amino-1'',2''- oxathiole-2'',2'-dioxide)pyrimidine (tsao) nucleoside analogues: highlyselective inhibitors of human immunodeficiency virus type 1 that are targeted at the viral reverse transcriptase. | a series of pyrimidine nucleoside analogues containing [2',5'-bis-o-(tert-butyldimethylsilyl)-3'-spiro-5''-(4''-amino- 1'',2''-oxathiole-2'',2''-dioxide)]-beta-d-ribofuranose as the pentose were found to inhibit human immunodeficiency virus type 1 [hiv-1(iiib)] replication at a concentration of 0.06-0.8 microm but were not cytotoxic at a 1000- to 10,000-fold higher concentration. these nucleoside derivatives were also effective against various other hiv-1 strains, including those resistant to 3' ... | 1992 | 1374900 |
| reversal of divergent differentiation by ras oncogene-mediated transformation. | in embryogenesis, ovarian surface epithelial cells and ovarian granulosa cells arise through divergent differentiation from a common mesenchymal precursor, the urogenital ridge. in the adult rat, ovarian surface epithelial cells are nonsteroidogenic and keratin positive, while ovarian granulosa cells are steroidogenic and keratin negative. in culture, kirsten murine sarcoma virus-transformed, tumorigenic ovarian surface epithelial cells continued to express keratin but also became steroidogenic. ... | 1992 | 1379124 |
| role of adhesion molecules in the immune reaction to m-msv-induced tumors. | we have investigated the in vivo role of 2 different adhesion molecules, lfa-1 and lecam-1, in the immune reaction to moloney-murine-sarcoma-virus(m-msv)-induced tumors, which undergo a peculiar spontaneous regression due to generation of a strong virus-specific cytotoxic-t-lymphocyte(ctl) response. repeated administration of anti-lfa-1 monoclonal antibody (fd441.8 mab), i.p. or at the site of virus inoculation, enhanced tumor growth and delayed regression, while i.p. administration of anti-leca ... | 1992 | 1385341 |
| some pathogenic aspects of murine sarcoma virus (moloney) in rats. | the oncogenic effect of the murine sarcoma virus (moloney) was tested in rats. host-age and virus-dose dependent variations in the pathogenic spectrum were found. four tumour "stages" were described: progressively lethal; lethal after long stationary period; complete tumour regression; tumour reoccurrence after complete regression. virus recovery was highest from the progressively growing tumours and in the reoccurred neoplasms, while no virus was found in stationary tumours or in those sites ... | 1975 | 1117696 |
| over-expression of the epidermal growth factor receptor in human breast cancer cells fails to induce an estrogen-independent phenotype. | an association exists in primary human breast tumors between high epidermal growth factor receptor (egfr) expression and a reduced number or even absence of estrogen receptors (er). to determine whether an increase in egfr expression might alter the estrogen responsiveness of an er-positive human breast cancer cell line, zr 75-1 cells were cotransfected with a plasmid containing the full-length cdna for the human egfr under the transcriptional control of the harvey murine sarcoma virus (hamsv) l ... | 1990 | 1698733 |
| normal human chromosome 1 carries suppressor activity for various phenotypes of a kirsten murine sarcoma virus-transformed nih/3t3 cell line. | in order to identify chromosomes that carry putative tumor-suppressor genes for the various phenotypes of kirsten sarcoma virus-transformed nih/3t3 (dt) cells, we performed microcell-mediated chromosome transfer into dt cells. we first isolated mouse a9 clones, containing a single human chromosome 1, 11 or 12 tagged with psv2-neo plasmid dna. then, chromosome 1, 11 or 12 was transferred from the a9 clones into dt cells by microcell fusion. the growth rate, colony-forming ability in soft agar and ... | 1990 | 1702413 |
| regulation of collagen gene expression by transformed human fibroblasts: decreased type i and type iii collagen rna transcription. | the regulation of collagen gene expression in normal diploid human fetal fibroblasts (kms-6 cells), and fibroblasts immortally transformed by treatment of kms-6 with co-60 gamma rays (kmst-6 cells) was compared to that of ones tumorigenically transformed by treatment of kmst-6 cells with harvey murine sarcoma virus (kmst-6-ras cells). synthesized collagenous protein decreased to approximately 30% of that of normal fetal fibroblasts in both transformed cell lines, and the relative rate of collage ... | 1991 | 1706744 |
| 9-[(2rs)-3-fluoro-2-phosphonylmethoxypropyl] derivatives of purines: a class of highly selective antiretroviral agents in vitro and in vivo. | a new class of compounds, 9-[(2rs)-3-fluoro-2-phosphonylmethoxypropyl] [(rs)-fpmp] derivatives of purines, is described that has selective activity against a broad spectrum of retroviruses [including human immunodeficiency virus type 1 (hiv-1) and type 2 (hiv-2)] but not other rna or dna viruses. this activity spectrum is completely different from that of the parental compounds, 9-[(2s)-3-hydroxy-2-phosphonylmethoxypropyl] [(s)-hpmp] derivatives of purines, which are active against a broad range ... | 1991 | 1711214 |
| tumours induced by moloney murine sarcoma virus are clonal in rats, not clonal in mice. | moloney murine sarcoma virus (m-msv) induces rapidly growing tumours in adult mice of most conventional strains. rats are less susceptible to m-msv oncogenesis, but the few rhabdomyosarcomas that do develop after viral inoculation of newborn animals closely resemble conventional malignancies: they develop after a long latency, grow progressively, and metastasize to regional lymph nodes and lungs. southern blot analysis with a v-mos-specific probe of m-msv-induced tumours in both species demonstr ... | 1992 | 1735735 |
| a divergent ets-related protein, elk-1, recognizes similar c-ets-1 proto-oncogene target sequences and acts as a transcriptional activator. | the ets oncogene superfamily consists of a family of sequence-specific dna-binding proteins that activate transcription. we have previously identified two new members of the ets oncogene superfamily, namely elk-1 and elk-2. in this report we show that the recombinant elk-1 protein expressed in bacteria, like the c-ets-1 proto-oncogene, binds in a sequence-specific manner to moloney murine sarcoma virus long terminal repeat, e74 target sequences and the pea3 motif (polyoma enhancer), but does not ... | 1992 | 1741166 |
| processing and secretion of human carboxypeptidase e by c6 glioma cells. | carboxypeptidase e (cpe) catalyses the removal of c-terminal basic amino acids and is implicated in the processing of peptides and hormones in secretory vesicles. the enzyme has been isolated in multiple forms from both soluble and membrane-bound compartments, and has been demonstrated to be co-secreted with peptides from pancreatic and adrenal cells. to address the question regarding the origin of the multiple forms of the enzyme, we have transfected a construct containing the cdna for human cp ... | 1991 | 1764034 |
| 9-(2-phosphonylmethoxyethyl)adenine (pmea) effectively inhibits retrovirus replication in vitro and simian immunodeficiency virus infection in rhesus monkeys. | 9-(2-phosphonylmethoxyethyl)adenine (pmea) is a potent and selective inhibitor of the in vitro replication of a number of retroviruses, including hiv-1 and hiv-2, simian immunodeficiency virus (siv), simian aids-related virus (srv), feline immunodeficiency virus (fiv) and moloney murine sarcoma virus (msv). pmea causes a dose-dependent suppression of the induction of anti-sivmacgp120 antibodies in siv mac-infected rhesus monkeys. complete suppression of anti-sivmacgp120 antibodies was achieved i ... | 1991 | 2059358 |
| single-dose administration of 9-(2-phosphonylmethoxyethyl)adenine (pmea) and 9-(2-phosphonylmethoxyethyl)-2,6-diaminopurine (pmedap) in the prophylaxis of retrovirus infection in vivo. | 9-(2-phosphonylmethoxyethyl)adenine (pmea) and 9-(2-phosphonylmethoxyethyl)-2,6-diaminopurine (pmedap) are selectively inhibitory to human immunodeficiency virus and other retroviruses. we have now investigated the effects of different pmea and pmedap treatment schedules in newborn mice infected with moloney murine sarcoma virus (msv). administration of a single dose of pmea or pmedap on the day of msv inoculation conferred a greater protective effect against msv-induced tumor formation than whe ... | 1991 | 1776876 |
| the expression of cathepsin b and other lysosomal proteinases in normal tissues and in tumors. | the mrna for the lysosomal proteinases cathepsins b, d, h, l, and s are broadly distributed in normal rodent tissues. although total cathepsin mrna levels generally parallel the protein catabolic activity of the tissues, the expressions of the individual enzymes do not appear to be linked. thus, the relative proportions of the individual messages are found to vary from tissue to tissue. further evidence for the independent regulation of lysosomal proteinase expression is derived from observation ... | 1991 | 1801719 |
| long-term explant culture of human colon and a 3-step transformation model for rat colonic epithelium. | our previous studies have suggested that colonic epithelium from rodents pretreated in vivo with suboptimal doses of carcinogen could be more easily maintained in explant culture. transformation of colonic epithelium from these explants may be induced by subsequent exposure to additional genotropic agents. therefore, we describe the development of a 3-step transformation model which uses (1) in vivo pretreatment with a suboptimal dose of 1,2-dimethylhydrazine (dmh) followed by (2) in vitro organ ... | 1991 | 1657027 |
| eye pathology in transgenic mice carrying a msv-sv 40 large t-construct. | several lines of transgenic mice carrying a transgene construct consisting of the regulatory enhancer element of the moloney murine sarcoma virus and the simian virus 40 genome coding for the sv 40 promoter and the large t antigen were established. we describe several abnormalities found in the eyes of transgenic animals of which heritable cataract formation, probably due to disturbances in primary lens fibre differentiation, showed a close correlation to large t antigen expression. additionally ... | 1991 | 1651251 |
| phosphorylation of v-mos ser 47 by the mitotic form of p34cdc2. | p85gag-mos is hyperphosphorylated during mitosis in normal rat kidney (nrk) cells transformed by moloney murine sarcoma virus ts110. we now report that p85gag-mos is phosphorylated in vitro by the mitotic form of the cdc2 kinase (p34cdc2, known as m-phase kinase) derived from virus-transformed cells. the major site of p85gag-mos phosphorylation by the m-phase kinase in vitro lies within the amino-terminal portion of the viral mos protein sequence spanning residues 45-53, as determined by tryptic ... | 1991 | 1833715 |
| derivatives of moloney murine sarcoma virus capable of being transcribed in embryonal carcinoma stem cells have gained a functional sp1 binding site. | the long terminal repeat (ltr) sequences of moloney murine leukemia virus and its closely related derivative moloney murine sarcoma virus (mo-msv) are incapable of directing transcription in embryonal carcinoma (ec) stem cells. the myeloproliferative sarcoma virus, a derivative of mo-msv, has several point mutations in the ltr and is transcribed more efficiently to allow productive infection of f9 ec cells. one of these mutations, at -166 with respect to the transcriptional start, creates a cons ... | 1991 | 1848307 |
| transduction of the cho aprt gene into mouse l cells using an adeno-5/aprt recombinant virus. | an adenovirus-5 recombinant virus adapt1 carrying the chinese hamster ovary (cho) adenine phosphoribosyltransferase (aprt) gene was constructed by insertion of a 2.5-kb fragment containing the complete cho aprt structural gene linked to a moloney murine sarcoma virus (msv) promoter into the e3 region of adenovirus-5. the cho aprt gene was in the opposite orientation to the adenovirus e3 promoter. mouse lapt- tk- (lat) cells expressed the cho aprt gene when infected with the virus, even at low mo ... | 1991 | 1887332 |
| inducibility of class ii major histocompatibility complex antigens by interferon gamma is associated with reduced tumorigenicity in c3h mouse fibroblasts transformed by v-ki-ras. | paired lines of c3h mouse fibroblasts transformed with murine sarcoma virus (kirsten strain) were prepared that express high or low levels of class ii major histocompatibility complex antigen after treatment with interferon gamma (ifn-gamma). here, we described a comparison of the tumorigenicity of these lines in euthymic syngeneic and thymus-deficient nu/nu mice and in mice depleted of ifn-gamma. the class ii-inducible cells are clearly less tumorigenic than the noninducible cells in syngeneic ... | 1991 | 1898659 |
| thy-1 as a negative growth regulator in ras-transformed mouse fibroblasts. | to identify molecules on the cell surface involved in negative growth regulation, we assumed that their amounts would be reduced after malignant transformation. we analyzed several proteins by fluorescence-activated cell sorter in mouse nih 3t3 and its transformed cell lines. surprisingly, the amount of thy-1, a cell surface glycoprotein anchored in the cell membrane by a glycophosphatidyl inositol linkage, was significantly decreased in the transformed nih 3t3 lines, especially in ras-transform ... | 1991 | 1670996 |
| ligation of membrane ig leads to calcium-mediated phosphorylation of the proto-oncogene product, ets-1. | recent studies have demonstrated that the nuclear protein, ets-1, which is preferentially expressed in lymphocytes, binds to the long terminal repeat of moloney murine sarcoma virus and htlv-1 and regulates gene expression. the association of ets-1 with dna has been shown to be lost when the protein is phosphorylated. thus, ets-1 may regulate gene expression in lymphocytes and this activity may be determined by its phosphorylation state. to address the possibility that ets-1 activity may be alte ... | 1991 | 1900874 |
| retroviral recombination during reverse transcription. | after mixed infection, up to half of related retroviruses are recombinants. during infection, retroviral rna genomes are first converted to complementary dna (cdna) and then to double-stranded dna. thus recombination could occur during reverse transcription, by rna template switching, or after reverse transcription, by breakage and reunion of dna. it has not been possible to distinguish between these two potential mechanisms of recombination because both single-stranded cdna and double-stranded ... | 1990 | 1690424 |
| alkalinization of the lysosomes is correlated with ras transformation of murine and human fibroblasts. | the ph of the intralysosomal compartment of fibroblasts in culture was monitored by measuring the fluorescence emission intensity at 530 nm of fluid phase pinocytosed fluorescein-conjugated dextrans (fitc-dextrans) excited at 488 and 457 nm. following the procedure of ohkuma and poole (ohkuma, s., and poole, b. (1978) proc. natl. acad. sci. u. s. a. (1978) 75, 3327-3331), a relationship was established between the fluorescence emission intensity of the fitc-dextrans and ph. this correlation was ... | 1990 | 1690732 |
| involvement of interferon-system in the regulation of cell growth and differentiation. | in this report we review the current knowledge on the involvement of the interferon (ifn) system in the regulation of cell growth and differentiation. we also summarize our own data which provide evidence for the strong correlation between ifn-mediated growth-arrest of transformed cells and the elevated enzymatic activity of an ifn-induced protein. similarly, it is demonstrated that elevated levels of ifn-induced proteins accompany the early phases of in-vitro cell differentiation. ifn-treatment ... | 1990 | 1698310 |
| intermediate filaments in rat ovarian surface epithelial cells: changes with neoplastic progression in culture. | interrelationships between neoplastic progression and the expression of intermediate filaments were examined in primary cultures, immortal lines, and kirsten murine sarcoma virus (kimsv) transformed lines of rat ovarian surface epithelial (rose) cells. immunofluorescence microscopy revealed abundant keratin filaments in all cells of primary cultures. in immortal, nontumorigenic lines, keratin filaments were detected in fewer cells, in smaller numbers, and in microscopically altered forms. the pe ... | 1992 | 1374615 |
| transformed rodent cells exhibit increased resistance to the carboxylic ionophores monensin and nigericin. | rodent fibroblasts transformed with the kirsten and moloney murine sarcoma viruses exhibit increased resistance to the growth inhibitory and cytotoxic action of the carboxylic na+/h+ ionophore, monensin. the inhibitory effect of monensin on cell proliferation requires exposure for periods longer than 24 hours. the virus-transformed cells also exhibit increased resistance to the k+/h+ ionophore, nigericin. since monensin is known to have significant effects upon the function and activity of the g ... | 1991 | 1993049 |
| cell-shape regulation and matrix protein p52 content in phenotypic variants of ras-transformed rat kidney fibroblasts. functional analysis and biochemical comparison of p52 with proteins implicated in cell-shape determination. | the 52 kda transformation-sensitive protein p52 was previously identified as a major substrate-associated component of normal rat kidney (nrk) fibroblasts [higgins & ryan (1989) biochem. j. 257, 173-182]. p52 selectively localized to cellular fractions enriched in substrate focal-contact sites and associated ventral undersurface elements. rapid attachment/spreading of nrk cells on to prepared p52 matrices and inhibition of fibroblast spreading by antibodies to p52 indicated that this protein par ... | 1991 | 1996963 |
| moloney murine leukemia virus tolerance in anti-cd4 monoclonal antibody-treated adult mice. | adult mice injected with moloney murine leukemia virus (m-mulv) 1 day after a short term treatment with anti-cd4 mab developed t cell lymphomas, or sarcomas when rechallenged with moloney murine sarcoma virus (m-msv). neoplastic development was correlated with virus spread, as thymic and peripheral t and b lymphocytes promptly expressed m-mulv-induced ag after virus introduction; no virus-specific ctl generation was detected in mltc. this failure, which was selective for m-mulv-induced ag, persi ... | 1991 | 1833453 |
| nk and lak susceptibility varies inversely with target cell mhc class i antigen expression in a rat epithelial tumour system. | several cell clones derived from cell lines obtained from a rat thyroid carcinoma, induced by in vivo injection of the kirsten murine sarcoma virus into thyroid gland, and from its spontaneous lung metastases were analysed for their major histocompatibility complex (mhc) class i antigen expression. the susceptibility to natural killer (nk) cell lysis of these clones, differing in their levels of mhc class i antigen expression, was determined and found to vary inversely with the target cell mhc l ... | 1991 | 2017656 |
| concomitant alterations of microfilaments and microtubules in human epithelial cells (hbl-100) in relation to their malignant conversion. | the organization of microfilaments and microtubules was studied in human epithelial hbl-100 cells at different steps in their malignant conversion. this conversion was obtained either spontaneously upon successive in vitro subcultures (approximately p. 70), or after superinfection of early passage non-tumorigenic cells (p. 28) with kirsten murine sarcoma virus. our results point out a clear relationship between the progression of cells toward malignancy, whatever the modality of malignant transf ... | 1991 | 2028179 |
| karyotype instability and altered differentiation of rat sarcoma cells after retroviral infection. | the karyotypic and phenotypic stability of cultured rat fibrosarcoma cells was challenged by infection with moloney murine sarcoma virus (momusv). after transformation, the spindle-like morphology of the parental hh-16 cl.2/1 cells had altered to a rounded phenotype, which was maintained in tumors produced by inoculating transformed cells into congenic animals. in contrast to the parental cells, transformed cells lacked cables of cytokeratins 14-16 and 19 and showed reduction of the mesenchymal ... | 1992 | 1377009 |
| potentiating effect of ribavirin on the in vitro and in vivo antiretrovirus activities of 2',3'-dideoxyinosine and 2',3'-dideoxy-2,6-diaminopurine riboside. | 2',3'-dideoxyinosine (ddi) and 2',3'-dideoxy-2,6-diaminopurine riboside (dddapr) are potent and selective inhibitors of human immunodeficiency virus (hiv) replication in mt-4 cells. they are also inhibitory to the transformation of c3h/3t3 cells by moloney murine sarcoma virus (msv). in vivo, they are only marginally effective in delaying msv-induced tumor formation, and mortality associated therewith in newborn nmri mice. when combined with ribavirin, ddi and dddapr become much more effective i ... | 1990 | 2123003 |
| production and characterization of a monoclonal antibody to the v-mos oncogene protein. | valuable information about proto-oncogenes and their physiological functions has been obtained by studying their expression in normal cells. however, the protein product of the c-mos gene, the cellular homologue of the transforming gene (v-mos) of moloney murine sarcoma virus, has not been detected in normal mouse cells or tissues. here, we have constructed a v-mos expression vector, pri-delta mos, which directs the synthesis of a truncated v-mos gene product, a protein a fusion protein. using t ... | 1991 | 1833309 |
| s-antigen and rod-opsin immunoreactions in midline brain neoplasms of transgenic mice: similarities to pineal cell tumors and certain medulloblastomas in man. | transgenic mice expressing the large t-antigen of the simian virus 40 (sv 40) under the control of 1) the enhancer of moloney murine sarcoma virus (msv) and 2) the sv 40 promoter develop undifferentiated neuroectodermal tumors located in the midline of the dorsal brain surface, abnormalities in lens fiber differentiation and retinal dysplasia. in this study the brain neoplasms of six adult animals and the brain of one 11-day old mouse were examined by conventional histology and immunocytochemica ... | 1990 | 2141872 |
| elevated expression of v-mos is correlated with altered differentiation of carcinoma cells. | permanent alterations of the epithelial differentiation pattern were investigated after infection of hh-16 cl. 4 adenocarcinoma cells with moloney murine sarcoma virus (momusv). transformed cell clones with fibroblastoid morphology were isolated and compared with clones of unchanged epithelioid phenotype. southern blot analyses showed intact momusv proviral genomes in copy numbers between 4 and 9 in the dna of the morphologically transformed cell clones as well as in the clones with unaltered mo ... | 1990 | 2148370 |
| the malignant histiocytosis sarcoma virus, a recombinant of harvey murine sarcoma virus and friend mink cell focus-forming virus, has acquired myeloid transformation specificity by alterations in the long terminal repeat. | the malignant histiocytosis sarcoma virus (mhsv), in contrast to other viruses with the ras oncogene, induces acute histiocytosis in newborn and adult mice. molecular structure and function studies were initiated to determine the basis of its unique macrophage-transforming potential. characterization of the genomic structure showed that the virus evolved by recombination of the harvey murine sarcoma virus (ha-musv) and a virus of the friend-mink cell focus-forming virus family. structural analys ... | 1990 | 2152823 |
| in vitro differentiation of rhabdomyosarcomas induced by nickel or by moloney murine sarcoma virus. | in vitro cultures and clonal derivatives have been established from rat rhabdomyosarcomas induced by moloney-murine sarcoma virus (msv) or by nickel sulfide; differentiation ability has been studied as expression of desmin, embryonic and adult myosin isoforms, alpha-actin isoforms and cellular fusion. the two rhabdomyosarcoma models showed different levels of myogenic differentiation. multinucleated myotube-like structures were frequently observed in cultures derived from nickel-induced tumours. ... | 1991 | 2039698 |
| ras p21 onco-protein in the sera of mice carrying an experimentally induced tumor and in human cancer patients. | we have established a model system to detect the presence of ras p21 in the sera of balb/c mice carrying tumors induced by a mouse cell line transformed with the harvey murine sarcoma virus in the presence of a helper friend murine leukemia virus. as determined by elisa and immunoblot assays, ras p21 in the serum increased with increased tumor growth. since ras genes have been found to be frequently activated in human tumours, we examined the levels of ras p21 in the sera of a variety of human c ... | 1990 | 2129802 |