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

Spleen cells (SC) both from BALB/c mice whose primary Moloney sarcoma virus (MSV)-induced sarcomas had spontaneously regressed and from normal, untreated BALB/c mice, were co-cultivated for 5 days with mitomycin-C-treated LSTRA cells; LSTRA is a BALB/c Moloney lymphoma which shares cell surface antigens with MSV-indiced sarcomas. These SC, referred to as CMR and CU cells, respectively, were shown to be cytotoxic to LSTRA cells in 3 h 51Cr-release assays; CMR cells showed, in most cases, the greatest lytic activity against LSTRA targets. The same SC were also reactive, in 20-h microcytotoxicity and 51Crassays, against target cells from a variety of transplanted sarcomas indiced by 3-methylcholanthrene (MCA) in Balb/c mice. The highest reactivity was seen when CMR or CU cells were tested against target cells from sarcoma lines that expressed an NB-ecotropic MuLV cross-reacting serologically with Moloney virus. Reactivity against isotope-labelled tumor cells expressing MuLV-associated cell surface antigens could be competititively inhibited by adding unlabelled tumor cells expressing such antigens. Finally, Winn assays were performed in which CMR cells strongly inhibited the outgrowth of cells from three sarcoma lines that express the NB-ecotropic MuLV. There was less but significant inhibition of cells from some other MCA sarcomas, either negative for the expression of MuLV-associated antigens or expressing the N-ecotropic endogenous BALB/c MuLV. CU cells enhanced tumor outgrowth in Winn assays at least as often as they inhibited it.
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PMID:Cell-mediated reactivity to antigens shared by Moloney-virus-induced lymphomas (LSTRA) and certain 3-methylcholanthrene-induced mouse sarcomas. 8 27

Cell lines were established in vitro from respiratory tract carcinomas induced in rats by carcinogenic, polycyclic hydrocarbons. Propagation of the carcinoma lines in vitro lead to a progressive decrease in tumorigenicity. Tumor transplantation studies in X-irradiated, immunosuppressed recipients and in immunologically reconstituted recipients suggested that the cells are rejected because of their immunogenicity, since a high incidence of tumors was observed in X-irradiated recipients but not in normal or X-irradiated, reconstituted recipients. When immunologically competent rats were immunized with cells from an in vitro tumor line, strong tumor transplantation resistance resulted. Similar immunization with the corresponding in vivo tumor line caused very little if any protection, and immunization with a non-cross-reacting sarcoma line grown in vitro did not produce immunological protection against carcinoma cell lines. A single in vivo passage of the in vitro-adapted tumor line in immunosuppressed recipients fully restored tumorigenicity. The increase in immunogenicity of carcinomas cultured in vitro appears to involve preexisting angigens indigenous to the carcinomas rather than new antigens acquired during tissue culture, such as antigens related to retroviruses, mycoplasmas, or heterologous serum.
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PMID:Increase in immunogenicity with concomitant loss of tumorigenicity of respiratory tract carcinomas during in vitro culture. 8 65

Moloney lymphomas and Moloney sarcomas share strong tumor antigens. In this report we analyze the cell-surface antigens on a Balb/c Moloney lymphoma, LSTRA, using hyperimmune sarcoma regressor sera (alphaMo) as a primary reagent. We also use heterologous anti-viral p30 and gp70 sera for a direct analysis of virion protein antigens on the LSTRA surface. Using radiolabeled alphaMo-binding assays, we demonstrate that LSTRA tumor antigens detected by these sera are all Moloney viral antigens; approximately 1/3 of these antigenic determinants are expressed on the intact virus, and the other determinants are revealed by detergent lysis of the virus. The major viral antigens expressed on the LSTRA cell surface are viral env gene products, whereas gag gene products are only sparsely represented. We conclude that alphaMo sera detect almost exclusively viral antigens on LSTRA cells, and these antigens are almost exclusively virion env gene products.
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PMID:A serologic comparison of Moloney lymphoma cell surface and Moloney oncornavirus antigens. 8 79

The cytotoxic T cell against a methylcholanthrene-induced sarcoma, S1509a, was induced in syngeneic mice by deliberate immunization with mitomycin C (MMC)-treated live tumor cells. The soluble tumor antigen (STA) extracted from the same tumor by 3 M KCl was, however, unable to induce the cytotoxic T cell upon immunization, although it was able to activate predominantly the suppressor T cell that then specifically suppressed the effect of the cytotoxic T cell against the homologous tumor. The suppressor T cell generated by STA had the same characteristics as those found in tumor-bearing animals: 1) The suppressor T cell has a very strict specificity against individual tumors; 2) The cell expresses cell surface determinants controlled by genes in the I-J subregion of the mouse H-2 complex. The activity of the cytotoxic T cell was completely inhibited by live tumor cells but not by STA, whereas that of the suppressor T cell was neutralized by STA. The results that cytotoxic and suppressor T cells are activated under different conditions, and that the antigenic determinants recognizable by these two cell types are not the same. The soluble extract contains only the determinants recognizable by the suppressor T cell, and the cytotoxic T cell can be activated only by the determinants associated with self antigen present on the surface of live tumor cells.
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PMID:Differential activation of cytotoxic and suppressor T cells against syngeneic tumors in the mouse. 9 95

Epithelioid sarcoma of the palm of 7 months' duration was observed in a 30-year-old man. Six months after wide surgical excision there was no evidence of recurrence or metastasis. By light microscopic examination the tumor showed typical nodular arrangement of malignant cells, with necrosis of these cells in the centers of the nodules. Patchy lymphocytic infiltrates were observed at the peripheries of the nodules and also extended in places between the tumor cells. Other types of inflammatory cells were practically absent. By electron microscopic examination it was noted that numerous neoplastic cells formed firm close contacts with lymphocytes. Considerable numbers of neoplastic ells so contacted were damaged or even disintegrated. The damaged tumor cells contained abundant lysosomes. The release of enzymes from these lysosomes in the disintegrating tumor cells might be an important factor underlying the extracellular tissue injury and necrosis so conspicuous in epithelioid sarcoma. The very slow growth of this neoplasm and its slow tendency to metastasize might be related to the high efficacy of lymphocyte-mediated defenses against this tumor.
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PMID:Epithelioid sarcoma: ultrastructural observation of lymphoid cell-induced lysis of tumor cells. 9 47

The tumor Angiogenesis Factor (T.A.F.) isolated from several human and animal neoplasms by J. Folkman and S. Kumar is a factor that induces the appearance of neovessels in the tumors. After describing the methods of vasculor, physiological, experimental and in some cases pathological proliferation, the author has compared the Angiogenesis in both the natural and neoplastic tissues, then, he's studies the tumoral growth the rate of which regularized by the T.A.F. The proving, the extraction and chemical nature of this factor have been reviewed. Afterwards, the author has called to mind the notion of tumoral ecology and the various possibilities of inhibition of the tumoral growth, that is founded on the inhibition of the Angiogenesis and the therapeutical possibilities of the T.A.F. in the fight against cancer. To end up with his study, the author is now considering the possibility of using the T.A.F., extract of the sarcoma of sticker as a complement to the electontherapy in the treatment of this neoplasm.
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PMID:[The tumor angiogenesis factor (TAF)]. 9 21

Sera from C3H/HeHa mice immunized with syngeneic methylcholanthrene-induced sarcoma react with allogeneic thymus, lymphoma and leukemia cells. The presence on leukemia and lymphoma cells of H-2 specificities expressed on normal cells of other H-2 haplotypes from the one in which the tumor originates is described. It was observed that the reaction of antisera to H-2 specificities with lymphoma cells was blocked by anti-MCA sarcoma sera. The cross-reactivity between MC sarcomas, thymus, leukemia and lymphoma cells is considered to be due to antibodies against these "alien" allospecificities.
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PMID:Alien H-2 allospecificities in murine chemically-induced tumors. 9 37

The reactivity of tumor-specific transplantation antigens (TSTAs) induced by SV40 and BK virus (BKV) was studied in Balb/Ccr mice with SV40-transformed tumor cells (mKSA-4AC). The mice, which had received BKV-transformed mouse or hamster cells, were highly resistant to the challenge with mKSA-4AC. The mKSA-rejected animals, however, were as susceptible as non-immunized ones to the subsequent challenge with Moloney sarcoma virus (Kirsten)-transformed cells. The result shows that BKV-transformed cells have a TSTA immunologically related closely to that induced by SV40.
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PMID:Induction of SV40-related transplantation immunity in mice by BK virus-transformed cells. 9 12

On two models of chemically induced tumors (cancer of the mammary gland and subcutaneous sarcoma) in rats the author has demonstrated the kinetics of biogenic amines transformations in the organism and their association with the developed structural-functional disorders in the connective tissue elements. It was found that the activity of connective tissue cells determined by the presence in them of such enzymes as nonspecific esterase, lipase and monoaminoxidase is directly dependent on the status of the intestinal enterochromaffin apparatus and the adrenal medulla and also on the presence of serotonin in connective tissue cells. The appearance of di-and polyamines in the pretumor period and their increase in the tumor period in conncective tissue noncellular structures indicate the enhancement of degeneration of these structures, while the presence of these substances in connective tissue cells evidences the suppression of their specific functions. It is believed that the source of production of di-and polyamines in the organism under tumor development is protein formations of noncellular structures of the connective tissue subjected to deorganization and destruction.
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PMID:[Changes in biogenic amines and connective tissue in the process of chemical carcinogenesis]. 9 97

In vivo immunogenicity and in vitro species-specific membrane antigens in tumor cells treated or untreated with glutaraldehyde (GA) were studied. Two different syngeneic Syrian hamster transplantable tumor cell lines (spontaneous liver cancer and SV40-induced sarcoma) not only lost immunogenicity after GA treatment but were responsible for enhancement of test-tumor growth in immunized animals. In vitro mixed hemadsorption test used for determination of species-specific membrane antigens in Syrian hamster, green monkey and interspecies hybrid cells revealed drastic alteration of antigens on the membrane of cells treated with GA.
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PMID:Sensitivity of TSTA and species-specific cell membrane antigens of tumor cells to glutaraldehyde treatment. 9 20


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