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

The growth and metastatic behavior of three human tumor cell lines and a human colon carcinoma previously passaged in vivo were compared between nude mice and scid mice after xenotransplantation. The three human tumor lines included a bladder carcinoma (T24B), a melanoma (RPMI 7931) and a lacZ gene-transduced breast cancer (MDA-MB-435 BAG). The lacZ gene codes for beta-galactosidase, which can be stained blue with chromogenic substrate X-gal, thus allowing the highly sensitive detection and quantitative examination of human cancer metastasis in host mice. Adult (7-14 weeks) NMRI nude and C.B-17 SCID mice were inoculated with 0.5-5 x 10(6) tumor cells s.c. Comparable take rate, latent period and growth rate of implanted tumors were observed in nude and scid mice for each of the cell lines tested. At the time of autopsy, which varied from 6 to 11 weeks after inoculation, a significantly higher incidence of spontaneous lung metastasis was discovered in scid mice (96%) than in age-matched nude mice (27%, total P less than 0.001). In vitro assays for NK cell-mediated cytotoxicity revealed no significant differences between the two strains of mice. Our results suggest that nude and scid mice are equally suitable for propagating human tumors. However, the metastatic capacity of human tumor cells appears to be better expressed in scid mice. Scid mice may therefore provide an advantageous model for the study of human tumor metastasis.
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PMID:Comparative studies between nude and scid mice on the growth and metastatic behavior of xenografted human tumors. 158 90

Tumor-reactive antibodies coupled to ricin or its A-chain (immunotoxins) have been used in rodents and humans to treat a variety of neoplastic diseases. Side-effects of such treatment include hepatotoxicity, vascular leak syndrome, myalgia and low grade fever. At high doses, severe toxicities include liver damage, pulmonary edema, aphasia, rhabdomyolysis and kidney failure. There have been a limited number of toxicologic studies on uncoupled ricin or its A-chain and none on deglycosylated A-chain. Since the latter has been utilized in "second generation" immunotoxins, the current studies were carried out to evaluate the toxicities induced by deglycosylated ricin A-chain (dgA) in mice. The administration of dgA to normal BALB/c mice causes early (24 h) weight loss and late (10 day) accumulation of ascites. These effects could be partially altered by changing the route of injection of dgA from i.v. to i.p. Thus, i.p. administration caused weight loss but not ascites, whereas i.v. administration caused both. Weight loss was associated with reduced fluid intake by the treated mice, and was not associated with increased levels of serum TNF-alpha. SCID mice injected with the same dose of dgA as normal BALB/c mice developed ascites, but it was of lesser severity, suggesting that a functional immune system, differences in microbial flora, or strain differences may be involved in the development of ascites.
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PMID:The toxicity of chemically deglycosylated ricin A-chain in mice. 162 27

Myeloma is one of the interleukin (IL)-6-related diseases to which abnormal expression of IL-6 has been reported to be linked. We examined the in vivo inhibitory effect of anti-human IL-6 receptor (IL-6R) antibody on human myeloma cell growth in mice. SCID mice were subcutaneously inoculated with solid tumor of the myeloma cell line S6B45 in which human IL-6 was acting as an autocrine growth factor. Ten intraperitoneal administrations of 100 micrograms of the anti-human IL-6R antibody PM1 at 48-h intervals strongly inhibited the growth of S6B45 cells when the administration started 24 h after tumor inoculation. The tumor growth inhibition in vivo was also observed by administration of the anti-human IL-6 antibody MH166 using the same procedure as for PM1. The inhibitory effect of PM1 was not significant when the administration started 5 or more days after tumor inoculation. This work indicates that anti-human IL-6R antibody, as well as anti-human IL-6 antibody inhibits human myeloma growth in vivo, and provides an animal model for testing the therapeutic value of agents such as antibodies to human IL-6, IL-6R and gp130, an IL-6R-associated signal transducer, in the treatment of human myelomas.
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PMID:Anti-human interleukin-6 receptor antibody inhibits human myeloma growth in vivo. 163 1

Aggressive B-cell lymphomas are occurring with increasing incidence among individuals infected with human immunodeficiency virus (HIV). Several lines of evidence implicate both Epstein-Barr virus (EBV) and c-myc activation in the pathogenesis of a major subset of these tumors. These observations prompted our investigation of interactions among EBV, c-myc, and HIV in primary B cells. We show that nonimmortalized peripheral B lymphocytes from EBV-seropositive, HIV-seronegative donors can be infected by HIV and that a subset of these lymphocytes become transformed. Malignant transformation was documented by several criteria. These cells displayed altered growth properties, propagating in 1% serum and cloning in soft agar, and formed invasive tumors of Burkitt lymphoma phenotype after subcutaneous injection into severe combined immunodeficiency mice. Such cells revealed marked enhancement of EBV DNA and RNA and of endogenous c-myc transcripts and protein. HIV-1 infection of already immortalized B-cell lines led to a similar upregulation of EBV and c-myc transcripts. These data indicate that HIV has properties of a transforming retrovirus, as it mediates two events linked to B-cell neoplasia: deregulation of c-myc and activation of EBV. They also raise the possibility of a role for HIV, apart from induction of immune suppression, in the pathogenesis of B-cell lymphoma in the acquired immune deficiency syndrome.
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PMID:Human immunodeficiency virus induction of malignant transformation in human B lymphocytes. 165 56

Epstein--Barr virus (EBV) is a latent human herpes virus that growth-transforms EBV receptor/CD21+ B cells and is associated with several high-frequency malignancies. Reactivation of latent EBV occurs in approximately 1/3 of organ graft recipients and a majority of AIDS patients; EBV-positive B lymphoproliferative lesions represent often fatal complications in organ transplantation and late-stage AIDS. Although such lymphomas can arise from endogenous virus, the high tumor risk in EBV-seronegative transplant recipients implies de novo infection, in particular virus transmission with intra-graft B lymphocytes. Since SCID mice engrafted with human lymphocytes (SCIDhum) typically develop endogenous EBV+ (human) tumors in their graft it is difficult to study exogenous virus transmission in this model. We here demonstrate that beige/nude/xid mice engrafted with human lymphoid cells (BNXhum) selectively accept human B but not T cell grafts. Unexpectedly these mice fail to develop endogenous lymphomas observed in SCIDhum mice engrafted in parallel. However, injection of as few as less than 500 EBV particles produces rapidly fatal, polyclonal lymphomas in BNXhum animals. This virus sensitivity of BNXhum approaches conditions for EBV transmission with organ grafts.
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PMID:Exogenous but not endogenous EBV induces lymphomas in beige/nude/xid mice carrying human lymphoid xenografts. 165 5

Epstein-Barr virus (EBV) carrying malignant lymphomas of the central nervous system are increasing owing to the increasing numbers of immunodeficient patients. To further understand the pathogenesis of these tumors, we studied the invasiveness of four EBV-immortalized lymphoblastoid cell lines in the brains of immunodeficient mice and the expression of adhesion molecules during this process. We injected four EBV-infected human lymphoblastoid cell lines intracerebrally into nude as well as SCID/SCID CB17 mice. Within 13 to 14 days, lethal brain lymphoproliferative lesions resulted in SCID mice, whereas similar lesions developed in 21 to 24 days in nude mice. Atypical large lymphoid cells aggressively infiltrated brain parenchyma, ventricular, and subarachnoid spaces. No difference in invasiveness was found between the monoclonal lymphoblastoid cell lines grown in long-term culture and polyclonal lymphoblastoid cell lines grown for a shorter duration. Tumors retained the same human immunoglobulin expression and activation antigen profile as the original cell lines. Furthermore, tumors expressed human LFA-1/ICAM-1 and the tumor blood vessels strongly expressed murine ICAM-1, but not MECA 79. Mice injected intracerebrally with peripheral blood leukocytes or normal bone marrow cells from an EBV seronegative individual failed to form tumors confirming the pivotal role for EBV in this process. SCID mice offer advantages for studying central nervous system lymphoproliferative disease.
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PMID:SCID/human mouse model of central nervous system lymphoproliferative disease. 168 2

We reasoned that the SCID-hu mouse could provide an appropriate lymphoid or stromal microenvironment to support the growth of primary human lymphoma. Heterotransplantation of nine cases of primary T-cell non-Hodgkin's lymphoma (NHL) into untreated SCID mice and SCID mice reconstituted with human fetal thymus, spleen, and liver (SCID-hu) resulted in the development of lymphoid tumors in five (56%) cases. Two clonal T-cell NHL grew after a mean of 90 days after injection of primary lymphoma cell suspensions into the thymus xenografts in SCID-hu mice and failed to grow in a variety of sites in SCID mice, except for small tumors that developed after a long (157-day) latency period after intracranial injection of tumor cell suspensions into weanling SCID mice. Successful serial transplantation of NHL in SCID and SCID-hu mice required the presence of a human lymphoid or tumor microenvironment, and was enhanced by pretreating the SCID mice with 175 rad radiation and antiasialo antisera. Analysis of the primary and transplanted T-cell tumors showed identical patterns of T-cell surface markers by flow cytometry and immunophenotyping of fixed tissue sections, and, in one case, reactivity with a specific monoclonal antibody to V beta 5.1. Genotyping of the transplanted tumors showed T-cell receptor gene rearrangements identical to those present in the primary tumors. In one case, the presence of Epstein-Barr virus-positive B cells in association with the primary tumor resulted in the growth of a lymphoblastoid B-cell neoplasm in addition to the malignant T-cell lymphoma after transplantation of tumor fragments to SCID mice. The data support the hypothesis that a human lymphoid microenvironment enhances the growth of T-cell NHL in SCID mice. The SCID-hu thymus graft provides an apparently unique microenvironment that supports the growth of primary T-cell NHL, and can be used to study the interaction between lymphoma cells, nontransformed lymphoid cells, and the surrounding stromal microenvironment in vivo.
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PMID:Growth of primary T-cell non-Hodgkin's lymphomata in SCID-hu mice: requirement for a human lymphoid microenvironment. 182 59

When human peripheral blood lymphocytes (PBLs) from Epstein-Barr virus (EBV)-seropositive donors are injected intraperitoneally into SCID mice, EBV+ B cell tumors develop within weeks. A preliminary report (Mosier, D. E., R. J. Gulizia, S. M. Baird, D. D. Richman, D. B. Wilson, R. I. Fox, and T. J. Kipps, 1989. Blood. 74(Suppl. 1):52a) has suggested that such tumors resemble the EBV-positive malignancy, Burkitt's lymphoma. The present work shows that generally the human (hu) PBL-SCID tumors are distinct from Burkitt's lymphoma and instead resemble lymphoblastoid cell lines (LCLs) generated by EBV-infection of normal B cells in vitro in terms of: (a) their cell surface phenotype, with expression of B cell activation antigens and adhesion molecules, (b) normal karyotype, and (c) viral phenotype, with expression of all the transformation-associated EBV latent proteins and, in a minority of cells, productive cycle antigens. Indeed, in vitro-transformed LCLs also grow when inoculated into SCID mice, the frequency of tumor outgrowth correlating with the in vitro growth phenotype of the LCL which is itself determined by the identity of the transforming virus (i.e., type 1 or type 2 EBV). Histologically the PBL-derived hu-SCID tumors resemble the EBV+ large cell lymphomas that develop in immuno-suppressed patients and, like the human tumors, often present at multiple sites as individual monoclonal or oligoclonal foci. The remarkable efficiency of tumor development in the hu-SCID model suggests that lymphomagenesis involves direct outgrowth of EBV-transformed B cells without requirement for secondary genetic changes, and that selection on the basis of cell growth rate alone is sufficient to explain the monoclonal/oligoclonal nature of tumor foci. EBV+ large cell lymphoma of the immunosuppressed may arise in a similar way.
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PMID:Epstein-Barr virus (EBV)-associated lymphoproliferative disease in the SCID mouse model: implications for the pathogenesis of EBV-positive lymphomas in man. 184 72

Cryopreserved cell suspensions of freshly excised melanoma metastases from nine patients were injected s.c. into C.B-17 severe combined immunodeficiency (SCID) mice. All 9 tumors grew as s.c. masses and six of nine were successfully transplanted into other SCID mice. Transplant inocula as low as 5 x 10(5) cells resulted in 100% tumor incidence. Moreover, seven of nine tumors metastasized, five from the original s.c. implants and two from transplanted s.c. tumors. Metastases were detected mainly in the lungs but also were found in abdominal viscera (liver, spleen, and pancreas) and thoracic lymph nodes. Flow cytometric analysis showed that expression of a panel of melanoma antigens, melanoma-associated proteoglycan, ganglioside GD3, and ganglioside GD2, was maintained with SCID passage. The original tumor inocula contained a variable percentage of tumor-associated lymphocytes (1-76%). Flow cytometry analysis indicated that these were mainly CD3+ T-cells. However, there was no correlation between the percentage of tumor-associated lymphocytes and the time required for development of a palpable tumor after s.c. injection or the ability to metastasize. These results demonstrate the growth and spontaneous metastasis of fresh human melanoma in SCID mice and suggest that this model could be important for therapeutic and basic biological studies.
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PMID:Growth and metastasis of fresh human melanoma tissue in mice with severe combined immunodeficiency. 189 83

In vivo studies on human malignant tumors are limited because of a lack of suitable animal models. In this study, the usefulness of SCID (severe combined immunodeficiency) mice, deficient in functions of both T- and B-lymphocytes, was evaluated. Inbred SCID mice were kept in isolated cages and 2 x 10(7) cells of KU-7, an established bladder carcinoma cell line, were inoculated in the subcutaneous tissue of the flank region of six SCID mice. Athymic nude mice were inoculated by the same method and served as the controls. The KU-7 cells were taken within 14 days in the injected region in all six SCID mice, while in only five out of eight nude mice. Tumors subsequently formed at the site of inoculation in these mice were confirmed to be transitional cell carcinomas histologically and intra-abdominal metastases were noted in two SCID mice. We conclude that SCID mice provide an ideal in vivo model for experimental studies of human urologic malignant tumors.
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PMID:SCID mice: a suitable model for experimental studies of urologic malignancies. 189 40


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