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)

Immunotherapy utilizing the adoptive transfer of lymphokine activated killer (LAK) cells in conjunction with recombinant interleukin 2 (RIL-2) is capable of reducing established metastatic cancer in a variety of animal tumor models. A major difficulty in the application of these efforts to the treatment of human cancer has been the activation in vitro of up to 2 X 10(11) human peripheral blood lymphocytes obtained by repeated leukaphereses. We have thus developed optimal and simplified techniques for the generation of human LAK cells for use in clinical trials. We have found that 1.5 X 10(9) lymphocytes separated on Ficoll-Hypaque gradients and incubated in 1000 ml of culture medium in a 2.3 liter roller bottle with 1000-1500 U of RIL-2 per ml, generated LAK cells capable of killing fresh human tumor cells in a 4 h chromium release assay. The culture medium used was RPMI 1640 with 2 mM glutamine, 2% heat-inactivated human AB serum, 50 micrograms/ml streptomycin and gentamicin and 50 U/ml penicillin. This technique allows activation of sufficient numbers of cells in a research laboratory setting to conduct human clinical trials. The administration of LAK cells generated in this fashion can mediate the regression of human tumors when administered in conjunction with IL-2.
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PMID:Large scale production of human lymphokine activated killer cells for use in adoptive immunotherapy. 348 92

Incubation of resting lymphoid cells with recombinant interleukin 2 (IL-2) in vitro leads to the generation of lymphokine activated killer (LAK) cells capable of lysing fresh tumor cell suspensions in short-term chromium-release assays. Our previous studies (7) have demonstrated that the injection of LAK cells plus low doses of recombinant IL-2 were capable of inhibiting the growth of pulmonary metastases. We have now explored the ability of high doses of recombinant IL-2, administered systemically, to generate LAK cells in vivo, and to mediate antitumor effects directly. Administration of increasing doses of recombinant IL-2 intraperitoneally resulted in the generation of LAK cells in the spleens of recipient mice. Doses of 100,000 U recombinant IL-2 administered intraperitoneally approximately every 8 h for 5 d were capable of dramatically inhibiting established 3-d pulmonary metastases from the MCA-105 and MCA-106 syngeneic sarcomas and the syngeneic B16 melanoma in C57BL/6 mice. Grossly visible metastases present at 10 d after tumor injection also underwent regression following IL-2 therapy. Surprisingly, established 10 d pulmonary metastases were more susceptible to the effects of IL-2 than were the smaller 3 d pulmonary metastases. All antitumor effects of the systemic administration of recombinant IL-2 were eliminated if mice received prior treatment with 500 rad total body irradiation. The administration of high doses of recombinant IL-2 was also capable of inhibiting the growth of 3-d established subcutaneous tumors from the MCA-105 sarcoma, and of mediating the inhibition of growth and regression of established palpable subcutaneous MCA-105 sarcomas. Lymphocytes, which appeared morphologically to be activated, were present at the site of regressing tumor, and it appears that the mechanism of the antitumor effect of recombinant IL-2 administered systemically is via the generation of LAK cells in vivo, although this hypothesis remains to be proven. The ready availability of high doses of recombinant human IL-2, and the demonstration of antitumor effects seen in animal models have led us to the initiation of the clinical trials of recombinant IL-2 in humans.
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PMID:Regression of established pulmonary metastases and subcutaneous tumor mediated by the systemic administration of high-dose recombinant interleukin 2. 388 26

If natural killer (NK) cells play a role in immunosurveillance it might by expected that, during the metastatic process, selection would occur for tumour cells with reduced NK sensitivity. This hypothesis was tested in the rat by measuring the NK sensitivity of cells freshly isolated from metastases of syngeneic transplanted spontaneous mammary carcinomas. Lysis was measured in a 6-h chromium release assay using normal syngeneic spleen cells as effectors. Our studies led to the following conclusions. (1) Metastases developing at certain tissue sites (draining lymph node and lung, but not pericardium) were frequently composed of tumour cells with markedly reduced sensitivity to NK cells. (2) This resistance could generally be detected only if freshly isolated tumour cell population were studied; after a few days in culture, resistant metastasis-derived tumour cells usually regained normal NK sensitivity. (3) Resistance to NK cells was not always due to the loss of NK target structures; it could also result from an innate resistance to the NK lytic mechanism. (4) The tissue distribution of NK-resistant metastases suggested that if NK cells exerted an immunoselective pressure they did so at the tissue site rather than in the primary tumour or in the bloodstream.
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PMID:Tumour cells in metastatic deposits with altered sensitivity to natural killer cells. 731 71

A murine model for the immunotherapy of head and neck cancer was established. The AT-84 tumor, a spontaneously arising oral squamous cell tumor of C3H mice, was evaluated for susceptibility to lymphokine-activated killer (LAK) cells. In vitro chromium-release assays demonstrated that AT-84 is sensitive to LAK-cell-mediated killing. Furthermore, in vivo experiments employing a lung metastasis model demonstrated a 50% reduction in the number of metastases in LAK-cell-treated mice as compared with untreated controls (P2 = .001). These experiments showed that AT-84 is an appropriate model for the immunotherapy of head and neck cancer. This model should be invaluable for further study of the mechanisms involved in immune-mediated therapy of head and neck cancer.
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PMID:A murine model for the immunotherapy of head and neck squamous cell carcinoma. 756 39

Local polyethylene-glycol (PEG)-modified interleukin-2 (IL-2) immunotherapy of the guinea pig Line 10 (L10) tumor was previously demonstrated to evoke long-lasting systemic immunity after cure of the tumor and metastases. T cells, most likely the helper T cell subpopulation, were demonstrated to be crucial to the antitumor effects. Here we show that systemic immunity is induced within 7 days after the start of PEG-IL-2 therapy, indicating a rapid systemic priming of L10-specific T cells. No in vitro cytotoxic activity was detected in cell suspensions obtained from the primary tumor site, the regional lymph node or the spleen when isolated during (days 21 and 28) intratumoral treatment with 200,000 IU PEG-IL-2. These data confirm our earlier results obtained with 60,000 IU PEG-IL-2. Moreover, no cytolytic activity was observed in the chromium-release assay after in vitro restimulation with irradiated tumor cells. Specific L10 immunity can be transferred using spleen cell suspensions. Depletion of such a suspension of helper T cells resulted in rejection of the primary tumor in two out of four animals, but all the guinea pigs developed lymph node metastases. Removal of the cytotoxic/suppressor phenotype caused rejection of the dermal tumor in four of eight guinea pigs, but the capacity to prevent lymph node metastases was retained in all animals. Thus, depletion of either subtype reduces, but does not abrogate, the capacity to transfer L10 immunity with spleen cells. In conclusion, our data suggest that tumor cell killing through direct T cell cytotoxicity is not the main mode of action in PEG-IL-2-induced L10 tumor regression. PEG-IL-2 therapy induces early systemic immunity, resulting in rejection of a distant tumor, and the transfer of this immunity depends mainly on the presence of helper T cells, although cytotoxic T cells may also play a role.
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PMID:Specific tumor memory induced by polyethylene-glycol-modified interleukin-2 requires both helper and cytotoxic T cells. 788 83

Our previous study showed that the injection of mouse myeloma VKCK/RM4-IFN-tau cells secreting the fusion protein RM4/IFN-tau to syngeneic BALB/c mice resulted in tumor regression in 70% of mice after tumor inoculation. In this study, the VKCK/RM4-IFN-tau cell line was used to characterize the protective immunity subsequent to tumor inoculation. Our histologic findings demonstrated that, in the primary response to VKCK/RM4-IFN-tau inoculation, tumor regression is associated with macrophage infiltration. This macrophage-dominated regression further leads to a protective immunity against the 2nd challenge of parental VKCK tumor cells. FACS analysis and chromium release assays showed that the majority of T lymphocytes that mediated this anti-tumor immunity were CD8+ cytotoxic T lymphocytes (CTLs). Our animal studies further showed that the VKCK/RM4-IFN-tau cells were able to grow as aggressively as the parental VKCK cells in T lymphocyte deficient nude mice. The protective immunity started 7 days, became complete 10 days following and lasted up to at least 12 months subsequent to the tumor inoculation. The adoptive transfer of T lymphocyte-enriched spleen cells or CTLs also conferred significant protection against tumor growth of parental VKCK cells (p < 0.01). These data thus support the notion that genetically engineered tumor cells secreting IFN-tau may have potential use as tumor vaccines in preventing the development of tumor recurrence and/or metastases following the surgical removal of the primary tumors.
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PMID:Characterization of anti-tumor immunity derived from the inoculation of myeloma cells secreting the fusion protein RM4/IFN-tau. 888 33

This study was undertaken to investigate the effectiveness of interleukin-2 (IL-2) and gamma interferon (gammaIFN)-modified B16 melanoma cells in the immunotherapy of established melanoma pulmonary metastases. The genes for IL-2 and gammaIFN were introduced retrovirally into B16 melanoma cells. Transduction with the gammaIFN, but not the IL-2, gene caused significant increases in the expression of major histocompatibility complex (MHC) antigens on B16-gammaIFN cells. The in vivo tumor-forming capacity of both IL-2- and gammaIFN-transduced B16 cells was drastically reduced when the cells were inoculated subcutaneously (SC) in syngeneic C57BL/6 mice. After intravenous (IV) inoculation, most of the B16-gammaIFN cells were rejected, but B16-IL-2 cells were relatively tumorigenic and formed pulmonary metastases. C57BL/6 mice bearing 4-day established parental B16 lung metastases were treated with B16 parental (B16P) unmodified cells, IL-2- or gammaIFN-modified B16 cells, or a combination of both transduced cells. Treatment consisted of a weekly intraperitoneal (IP) injection of one million irradiated (10,000 rad) tumor cells alone or in combination with exogenous IL-2 for a total of three to four injections. Immunotherapy with B16 parental or B16-IL-2 secreting cells caused a moderate reduction in the number of lung metastases. However, mice treated with gammaIFN-secreting B16 cells showed a significant reduction or complete elimination of lung metastases. There was no additive effect for combining both IL-2- and gammaIFN-modified tumor cells in the immunotherapy. Exogenous IL-2 (50,000-100,000 U/day for 3 days) caused a significant enhancement of the immunotherapeutic benefit of the vaccines. Moreover, mice treated with gammaIFN-modified B16 cells survived longer than the other groups. Twenty-five percent of these mice were tumor free and remained alive for an observation period of 4 months. The in vitro cytolytic activity of splenocytes in chromium release assays did not correlate in every case with the in vivo antitumor effect of the treatment. Our findings have implications for the use of cytokine-modified cells for immunotherapy and for evaluating the therapeutic benefit of this novel treatment.
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PMID:Eradication of melanoma pulmonary metastases by immunotherapy with tumor cells engineered to secrete interleukin-2 or gamma interferon. 901 49

Adoptive transfer of activated autologous human macrophages obtained by in vitro differentiation of monocytes in culture has successfully undergone phase I clinical trials in patients with metastatic cancer. The efficacy of these autologous macrophages in the in vivo killing of human tumors has now to be demonstrated. GM-CSF was shown to increase the number of monocytes differentiating in culture into macrophages. These were then activated with IFN gamma which was reported as the best cytokine for tumoricidal activation of macrophages. The aim of this paper was to evaluate the in vitro tumoricidal activity of macrophages grown with GM-CSF and IFN gamma. This tumoricidal function was investigated by measurement of the cytolytic (chromium-51 release assay), cytostatic (anti-proliferative activity as measured by inhibition of [3H]-thymidine incorporation in two different assays) and cytotoxic (MTT assay) activities on two tumor cells lines, U937 and K562 (respectively highly sensitive and resistant to soluble TNF alpha). Our results demonstrated that GM-CSF-grown macrophages exhibited significant cytolytic, cytotoxic and cytostatic activities on U937 cells. These were partly enhanced by IFN gamma activation. In contrast, they had no lytic and lower cytotoxic and cytostatic activities on K562 cells, and these were not modified by IFN gamma activation. Our data provide valuable information for future in vivo studies using adoptively transferred autologous macrophages.
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PMID:Tumoricidal potential of human macrophages grown in vitro from blood monocytes. 941 98

Currently, there is no long-term effective treatment for unresectable hepatic malignancies. Salmonella sp. are known to naturally track to the liver during active infection. To develop a biological vector for delivery of Interleukin-2 (IL-2) to the liver for anti-tumor purposes, the avirulent and highly immunogenic chi 4550 strain of Salmonella typhimurium was used as a vector for IL-2. The gene for human IL-2 was cloned into plasmid pYA292 (renamed pIL-2) and inserted into the attenuated Salmonella typhimurium and renamed [chi 4550 (pIL-2)]. This transformant was found to produced biologically active IL-2 demonstrated by NK cell activation in a 4 hour chromium release cytotoxicity assay. To determine anti-tumor potential, MCA-38 murine adenocarcinoma cells were injected intrasplenically into C57BL/6 mice to produce hepatic metastases and metastases were subsequently enumerated after 12 days. Statistical significance was determined by ANOVA with Fisher's test for significance. Hepatic metastases enumerated by blinded observers revealed that the mean number of metastases was 106.4 in control mice, 103.7 in mice gavage fed attenuated salmonella without IL-2 [chi 4550(pYA292)], and 44.3 in mice fed the chi 4550(pIL2); (ANOVA: p < 0.01). Culture of livers and spleens in mice administered a single gavage dose of salmonella demonstrated persistent colonization for up to 4 weeks. No observable toxicity was seen to either IL-2 or salmonella. These studies demonstrate that the chi 4550(pIL2) is a novel form of in vivo biotherapy which produces biologically active IL-2 and employs the oral route of administration to stimulate an immune response against malignancy in the liver.
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PMID:Attenuated Salmonella typhimurium containing interleukin-2 decreases MC-38 hepatic metastases: a novel anti-tumor agent. 1085 31

All of these studies taken together highlight key areas that must be addressed in the future in order for the field to continue to move forward. These issues are many, including but not limited to method of delivery of dendritic cells to patients, maturation status of the dendritic cells, and methods of monitoring responses to these vaccines. Each of these requires some comment. Different strategies of immunization were used in these studies. DCs were injected at various times and in various locations, including intradermally/subcutaneously, intranodally, and intravenously. Investigation of the pattern of spread of subcutaneously injected fluorescently labeled DCs in the chimpanzee was studied at the University of Pittsburgh. Although rodent DCs had previously been shown to remain at the site of injection, these immature primate DCs migrated to draining lymph nodes and interact appropriately with T cells for as long as 5 days after administration. Data not shown in the same study reveal that intravenously administered DCs were undetectable in draining lymph nodes. Two groups have undertaken evaluation of route of administration of DCs in humans. The first of these examined migration of immature, indium-111-labeled dendritic cells after RNA-loading in metastatic cancer patients [44]. The DCs were injected either intravenously, subcutaneously, and intradermally. Only DCs injected intradermally were cleared from the injection site with migration to regional lymph nodes. The immunologic significance of these findings is unclear, however. Another study examined this issue by studying prostatic acid phosphatase (PAP) protein-loaded mature DCs injected intravenously, intradermally, and intralymphatically in prostate cancer patients [45]. Regardless of route of administration, T cell responses were induced as measured by proliferation when PBMCs in vitro were stimulated with the PAP protein. Cytokine analysis of the patients revealed that the majority of patients undergoing either intralymphatic or intradermal injection had increases in measurable interferon-gamma but that none of the intravenously-injected patients did. The intralymphatic and intradermal routes thus seem to lead to stronger Th1 responses. But no data was presented regarding the numbers of PAP precursors induced by vaccination nor their specificity/cytotoxicity. Another issue in DC administration that should also affect route of administration is maturation status of the dendritic cells. Many of the studies used immature dendritic cells to immunize patients whereas others used mature cells. A number of studies have demonstrated that maturation signals such as inflammatory cytokines and CD40 ligation lead to down-regulation of antigen processing and up-regulation of the chemokine receptor CCR7, which leads to homing to lymph nodes [46] as well as the MHC molecules, costimulatory molecules, and maturation markers [8,47,48]. In addition, different maturation agents and sequences of addition of these maturation agents may lead to differences in functions of dendritic cells [48-51]. Others have found that injection of immature DCs pulsed with influenza matrix peptide and KLH, and lead to greater numbers of influenza-specific T cells, but these cells had reduced interferon-gamma production and lacked killer activity [52]. Perhaps the most impressive results in a clinical trial, however, were gained by injecting similar cells loaded with melanoma peptides [21]. In addition, sequence of loading and maturation may be important in creating vaccines. One study using CEA peptides and CEA RNA found that optimal T cell presentation occurs when peptides are loaded after maturation with CD40 ligand and when RNA is transfected before maturation with CD40 ligand [53]. As all of these studies reveal, more investigation into the role of DC maturation as well as its timing and sequence is needed. Finally, a multitude of methods to detect response to vaccination have been attempted in all of the above studies. Many use DTH responses, but these may measure CD4 T cells instead of CD8 T cells. The availability of tetramers allows easier quantification of CTL precursors, but they provide no assessment of the function of these T cells. Enzyme-linked immunospot assays allow identification and quantification of numbers of cells producing cytokines such as interferon-gamma when encountering target antigens, but cytokine production may not correlate with tumor cell killing. Chromium release assays or flow cytometric assays for molecules such as perforin may be used to validate killing, but inability of many tumors to grow in vitro precludes direct assessment of tumor cell killing via this method. Other responses in human subjects may also be measured. Some of the cited studies yielded clinical responses that could be measured via physical examination or radiologic study. This is the exception rather than the rule, however. Others have monitored the decrease in serum tumor markers such as PSA or CEA. But these may not correlate directly with tumor burden. Indirect calculation of tumor burden by using quantitative PCR to estimate the number of circulating tumor cells in peripheral blood may be promising in this regard. Despite the lack of consensus as to what constitutes an effective response, most would agree that monitoring of these patients should include measures of both immunologic response and clinical tumor effect. All of this leads to the conclusion that DC-based cancer vaccines have progressed a great deal but that much work still needs to be done. Only rigorous bench top experimentation followed by careful patient selection and vaccine administration, and then by meticulous patient monitoring, will lead to advances in the field.
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PMID:Dendritic cell gene therapy. 1248 60


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