Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027627 (metastases)
 103,950 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Dendritic cells (DC) are antigen-presenting cells initiating primary and secondary immune responses. Since malignant tumors are able to escape immunologic control, DC might be prime candidates to activate the immune system against tumor cells. In an autologous system, a dynamic interaction among monocyte-derived DC (MoDC), T lymphocytes, and tumor cells obtained from melanoma patients could be noted. MoDC were generated from blood monocytes in the presence of GM-CSF, IL-4, and IFN-gamma. T cells were isolated either from peripheral blood or from lymph nodes. Melanoma cells were harvested from surgically removed tumor metastases. They were then gamma-irradiated and co-cultured with autologous MoDC and T lymphocytes. After 5 days, the lymphocytes showed a high proliferative activity and the majority of them were CD8-positive. In five cases tested, they revealed a high cytotoxic activity resulting in apoptosis of tumor cells. These findings suggest that MoDC are capable of initiating an effective specific anti-tumor response in a strictly autologous mixed lymphocyte tumor culture (MLTC), even though tumor-specific antigens had not been individually defined. Therefore (I) whole melanoma cells can serve as a source of antigen, (II) monocyte-derived dendritic cells may process and present melanoma-specific antigens resulting in a strong lymphocyte proliferation, (III) the majority of responding T lymphocytes are CD8-positive, and (IV) an acquired cytotoxic response eventually leads to apoptosis of the melanoma cells. The reaction demonstrated here permits to in vitro and quantitatively monitoring the effect of T cell directed immunotherapies such as the adoptive immunotherapy of tumors.
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PMID:Specific autologous anti-melanoma T cell response in vitro using monocyte-derived dendritic cells. 956 71

Growth of Lewis lung carcinoma (LLC-LN7) tumors results in an increase in CD34+ granulocyte-macrophage progenitor cells having natural suppressor (NS) activity. These CD34+ NS cells were capable of inhibiting the cytotoxic activity of tumor-reactive lymph node cells. In vivo studies showed that adoptive treatment of LLC-LN7 tumor-bearing mice with tumor-reactive lymph node cells plus IL-2 failed to reduce the development of metastases. Studies were conducted to determine if diminishing the levels of CD34+ NS cells would allow for improved anti-tumor effectiveness of the adoptively transferred cells. The suppressive activity of CD34+ cells toward the cytolytic activity of tumor-reactive lymph node cells could be blocked by in vitro culture of CD34+ cells with the differentiation-inducing hormone 1alpha,25-dihydroxyvitamin D3. Similarly, treatment of LLC-LN7-bearing mice with vitamin D3 alone diminished the levels of CD34+ NS cells within regional lymph nodes, spleens and tumors. This treatment resulted in an increased immune reactivity to autologous tumor, as shown by the production of IFN-gamma by lymph node cells in response to the presence of LLC-LN7 cells. The extent of tumor metastasis in mice receiving vitamin D3 treatment was also reduced. When tumor-reactive lymph node cells were adoptively transferred into these LLC-LN7-bearing mice that were receiving vitamin D3 treatment, there resulted a pronounced synergistic reduction in tumor metastasis. The results of this study show that treatment of tumor bearers with vitamin D3 to eliminate CD34+ NS cells improves the anti-tumor effectiveness of adoptively transferred tumor-reactive lymph node cells.
Clin Exp Metastasis 1998 Apr
PMID:Failure of tumor-reactive lymph node cells to kill tumor in the presence of immune-suppressive CD34+ cells can be overcome with vitamin D3 treatment to diminish CD34+ cell levels. 956 45

Using an experimental model of hepatic Echinococcus multilocularis infection in C57BL/6J mice, intraperitoneal administration of 0.8 microgram of recombinant IL-12 to mice with an established infection was shown to reduce the parasite burden as soon as two weeks after the end of treatment. At that time, in vitro Echinococcus multilocularis-induced spleen T cell proliferative responses as well as IFN-gamma and IL-5 production were higher in IL-12 treated mice than in untreated mice. Administration of 0.8 microgram of IL-12 at the time of infection was shown to be without effect on the parasite establishment. However, this treatment greatly inhibited the subsequent metacestode development. Indeed, ten weeks after infection, it induced a complete healing in 37.5% of mice. At that time, the development of metastases was inhibited in 68.75% of IL-12-treated mice. This reduction of parasite burden was mainly associated with a strong proliferation of spleen cells to E. multilocularis antigen and with a high IFN-gamma production. Altogether, our results show that IL-12 is of crucial importance in inhibiting the larval growth after the metacestode establishment in the liver and suggest that this cytokine could be of potential value in the treatment of human alveolar echinococcosis.
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PMID:In vivo treatment with recombinant IL-12 protects C57BL/6J mice against secondary alveolar echinococcosis. 957 51

IL-12 is a complex cytokine in both its structure and its range of biologic activities. Fusions of this heterodimeric molecule with an intact antitumor Ab were made to test the feasibility and efficacy of targeting IL-12 to tumors to elicit a local immune response. Fusion proteins composed of the human p35 and p40 subunits had IL-12 bioactivities that were nearly as potent on human immune cells as the rIL-12 standard, but were inactive on mouse cells. Hybrid IL-12 fusion proteins composed of mouse p35 and human p40, fused to Ab, were capable of inducing IFN-gamma, but were much less active on mouse spleen cells than a mouse IL-12 standard. Despite this relatively low activity, the hybrid fusion protein was as effective in a SCID mouse model as a fully active Ab-IL-2 fusion protein in eliminating established pulmonary metastases of CT26 colon carcinoma. Specific targeting of a human IL-12 fusion protein to metastatic prostate carcinoma xenografts was also shown to be effective in SCID mice transplanted with human lymphocyte-activated killer cells. These results demonstrate the importance of directing this potent cytokine to the tumor microenvironment and suggest an important alternative to systemic IL-12 administration or gene therapy for increasing its therapeutic index.
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PMID:Antibody-IL-12 fusion proteins are effective in SCID mouse models of prostate and colon carcinoma metastases. 963 39

Expression of HLA class I molecules is essential for the recognition of tumor cells by CD8+ T cells. In this study, 48 bioptic samples of 42 patients in all stages of melanoma were investigated after short-time cultivation of tumor cells. To confirm melanocytic origin of cultured cells, samples were screened for mRNA expression of melanoma markers gp100, tyrosinase, MAGE-3, MelanA, and MUC18 by reverse transcriptase-polymerase chain reaction. Surface expression of specific HLA-A and -B allospecificities on melanoma cells were analyzed with a standard microcytotoxicity assay after stimulation with interferon (IFN)-alpha and compared with the background found in peripheral blood mononuclear cells from the corresponding patients. Immunohistochemistry and flow cytometry confirmed specific losses in cases where the appropriate monoclonal antibodies were available. The level of expression of HLA-I, HLA-II, and intercellular adhesion molecule 1 antigens on melanoma cells cultured in the presence or absence of IFN-alpha and IFN-gamma was determined cytofluorometrically. All cell cultures tested were found to be positive for one or more melanocytic markers by reverse transcriptase-polymerase chain reaction. The specific HLA-I alleles on the cultured cells were detectable in 45 of 48 samples. In 11 cases a specific loss of one HLA-I allele was observed (2 x A2, B7, B8, B18, 4XB44, B47, B49). Ten of these samples were derived from locoregional lymphnode metastases or from distant metastatic tumors. Only one sample from a primary melanoma showed a specific loss of HLA-I (B47). IFN-alpha upregulated expression of HLA-I up to 4-fold. IFN-gamma enhanced the appearance of HLA-II up to 35-fold and the expression of intercellular adhesion molecule 1 up to 40-fold. Selective loss of HLA-I allospecificities might be a major step in tumor progression.
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PMID:Higher frequency of selective losses of HLA-A and -B allospecificities in metastasis than in primary melanoma lesions. 974 Feb 47

High-dose TNF-alpha plus chemotherapy, with or without IFN-gamma, can be safely administered regionally through isolated limb perfusion. This procedure produced between 70% and 80% complete remission in cases of in transit melanoma metastases and between 25% and 36% complete remission in cases of inextirpable soft-tissue sarcomas. Dual targeting is involved; TNF-alpha and IFN-gamma induce apoptosis of angiogenic endothelium, while melphalan induces apoptosis of tumour cells.
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PMID:Clinical applications of TNF-alpha in cancer. 979 39

We have previously demonstrated that IFN-gamma causes cell growth inhibition and up-regulation of MHC antigens in human renal cell carcinoma cell lines. In this study, we have investigated the therapeutic potential of IFN-gamma for the treatment of 5-day established pulmonary metastases induced by i.v. injection of Renca cells, a murine renal adenocarcinoma. We found that systemic injections of IFN-gamma significantly reduced the number of lung metastases in a dose-dependent manner and increased mouse survival. Histological evaluation of IFN-gamma-treated lungs showed residual small tumor nodules containing extensive necrosis and mononuclear infiltrates. Immunohistochemistry studies on lung sections showed macrophage infiltration into tumor nodules, and in vivo depletion of macrophages partially inhibited IFN-gamma antitumor effect, suggesting a role for the macrophages in tumor destruction. Lymphocyte depletion of either natural killer (NK) cells or CD4+ or CD8+ T-cell subsets or both T-cell subsets did not affect the IFN-gamma effect, whereas depletion of both NK and T cells decreased the antitumor activity of IFN-gamma. These data indicate that neither T cells nor NK cells are essential for this activity but that either lymphocyte population can contribute to the IFN-gamma effect. An optimal dose of IFN-gamma inhibited by 60% the growth of Renca cells treated for 3 days in vitro, but this effect was transient and less pronounced in a long-term colony assay, suggesting that IFN-gamma direct growth inhibition may play a role but may not be sufficient to mediate its antitumor effect in vivo. In vitro, IFN-gamma caused up-regulation of class I MHC antigens and induction of class II antigen expression in Renca cells, an effect that may enhance Renca immunogenicity but may be relevant only when a T-cell response is elicited. A sequential administration of IFN-gamma followed by interleukin 4 was therapeutically better than IFN-gamma alone for the treatment of advanced pulmonary metastases, probably due to different antitumor mechanisms induced by these two cytokines.
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PMID:Inhibition of murine renal carcinoma pulmonary metastases by systemic administration of interferon gamma: mechanism of action and potential for combination with interleukin 4. 981 66

IFN-gamma is a potent immunomodulator, which has activity against melanoma in vitro and in murine models. However, preclinical data suggests that the optimal therapeutic and immunomodulatory dose may not be the maximally tolerated clinical dose. We conducted a Phase II/III trial in good prognosis patients with metastatic melanoma to determine whether a therapeutic and immunomodulatory dose-response curve of IFN-gamma could be identified, and whether the two could be correlated. Ninety-eight patients with metastatic melanoma were randomized to one of seven dose levels of IFN-gamma ranging from 0.01 to 0.90 mg/m2. All patients were required to have s.c., skin, soft tissue, or nodal disease, although visceral disease was also allowed, and no more than one prior chemotherapy regimen. Patients received IFN-gamma as a 1-h i.v. infusion three times per week for at least 8 weeks or until progressive disease. Ninety-five patients were eligible for toxicity evaluation; 81 were eligible for tumor response. Four patients responded to therapy (response rate, 5%) at three dose levels: two patients at 0.01 mg/m2 and one each at 0.5 and 0.9 mg/m2. The duration of response ranged from 5 to 58 weeks. Toxicities were typical of IFNs and included flu-like constitutional symptoms. No dose-response relationship was identified for efficacy. A dose-response relationship for toxicity was observed only for fever and chills (p = 0.035) and hepatic toxicity (p = 0.034). IFN-gamma has minimal activity in metastatic melanoma, and a therapeutic dose-response curve could not be identified. Although potent dose-dependent effects on immunomodulation were identified (J. M. Kirkwood, J. Bryant, J. H. Schiller, M. M. Oken, E. C. Borden, and T. L. Whiteside. Immunomodulatory function of interferon gamma in patients with metastatic melanoma: results of a phase IIB trial in subjects with metastatic melanoma: ECOG Study E4987, submitted for publication), this biological activity does not translate into therapeutic activity in the metastatic disease setting in this trial.
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PMID:Eastern cooperative group trial of interferon gamma in metastatic melanoma: an innovative study design. 981 86

Dendritic cells (DC) are regarded as attractive candidates for cancer immunotherapy. Our aim is to improve the therapeutic efficacy of DC-based tumor vaccine by augmenting DC preferential chemotaxis on T cells. Mouse bone marrow-derived DC were transduced with lymphotactin (Lptn) gene by adenovirus vector. The supernatants from Lptn gene-modified DC (Lptn-DC) were capable of attracting CD4+ and CD8+ T cells in a chemotaxis assay, whereas their mock control could not. Lptn expression of Lptn-DC was further confirmed by RT-PCR. Lptn-DC were pulsed with Mut1 peptide and used for vaccination. Immunization with the low dose (1 x 10(4)) of Mut1 peptide-pulsed DC induced weak CTL activity, whereas the same amounts of Mut1 peptide-pulsed Lptn-DC markedly induced specific CTL against 3LL tumor cells. A single immunization with 1 x 10(4) Mut1 peptide-pulsed Lptn-DC could render mice resistant to a 5 x 10(5) 3LL tumor cell challenge completely, but their counterpart could not. The protective immunity induced by Mut1 peptide-pulsed Lptn-DC depends on both CD4+ T cells and CD8+ T cells rather than NK cells in the induction phase and depends on CD8+ T cells rather than CD4+ T cells and NK cells in the effector phase. Moreover, the involvement of CD28/CTLA4 costimulation pathway and IFN-gamma are also necessary. When 3LL tumor-bearing mice were treated with 1 x 10(4) Mut1 peptide-pulsed Lptn-DC, their pulmonary metastases were significantly reduced, whereas the same low dose of Mut1 peptide-pulsed DC had no obvious therapeutic effects. Our data suggest that Lptn-DC are more potent adjuvants for peptide delivery to induce protective and therapeutic antitumor immunity.
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PMID:Lymphotactin gene-modified bone marrow dendritic cells act as more potent adjuvants for peptide delivery to induce specific antitumor immunity. 983 11

A B16 melanoma-specific CD8+ T cell line (AB1) was established from the spleen cells of C57BL/6 mice cured of B16 melanoma with interleukin (IL)-12 treatment. The AB1 line exclusively used T cell receptor Vbeta11. The AB1 cells exhibited a cytolytic activity against both syngeneic B16 melanoma and allogeneic P815 mastocytoma, whereas a cold inhibition assay revealed specificity of the AB1 cells against B16 melanoma. Their lostability to kill a class I loss variant of B16 melanoma was restored by the transfection of H-2Kb gene. In addition, their interferon (IFN)-gamma production was significantly suppressed by the addition of anti-H-2Kb monoclonal antibody, and RT-PCR analysis showed that the AB1 line expressed the mRNA encoding IFN-gamma, but not IL-4 or IL-10. The experiment using synthetic peptides of tyrosinase-related protein-2 (TRP-2) revealed that the AB1 cells could recognize TRP-2(181-188) peptide. Moreover, the AB1 cells showed an in vivo antitumor effect against established pulmonary metastases of B16 melanoma. Overall, these results indicate that the Tc1-type Vbeta11+ AB1 cells exert an antitumor activity against syngeneic B16 melanoma through recognition of TRP-2(181-188) peptide in an H-2Kb-restricted manner.
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PMID:Characterization of B16 melanoma-specific cytotoxic T lymphocytes. 987 72


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