Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0178874 (tumor progression)
 40,807 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A detailed analysis of the immune system response has been performed during the development and progression of dimethylbenz(a)anthracene (DMBA)-induced rat mammary tumors. For this aim, a number of immune parameters (thymocyte and splenocyte proliferative response to T-dependent mitogens, antibody production, lymphocyte subset phenotyping, interleukin 2 receptor expression in resting and activated lymphocytes, thymus morphology and morphometry), were correlated with tumor appearance and growth at different (-7, 0, +15, +30, +60, +90, and +120 days) time intervals after intragastric administration of DMBA, in the absence or the presence of a concomitant treatment with the thymic pentapeptide thymopentin (TP5). A profound and time-dependent immunosuppression characterized the treatment with the carcinogen. Both cell-mediated and humoral immune responses showed a 50% inhibition 2 weeks after DMBA administration, with a peak after 30 days, followed by a plateau until 120 days of observation. The mechanism responsible for reduced ability of thymocytes and splenocytes to respond to both Con-A and PHA was explained by the significant inhibition of one of the key steps of T cell activation, namely the expression of IL-2 receptor in lymphocytes from DMBA-treated animals. The flow cytometric analysis of lymphocyte subpopulations revealed an important reduction in the overall populations of thymocytes and splenocytes. At the thymus gland level, a dramatic reduction of double positive CD4+CD8+ and a decrease of CD4+CD8- and CD4-CD8+ were observed, together with a marked atrophy of the thymic cortex, and impairment of the thymic microenvironment. One hundred and twenty days after DMBA administration, approximately 60 to 70% of the animals developed tumors with a mean tumor surface area of 2.88 +/- 0.86 cm2, and a number of 2.44 +/- 1.0. Treatment with TP5 (100 ng/animal, three times a week, starting a week before DMBA), produced specific effects on different immune compartments and tumoral growth, characterized by a significant reversal of immune depression with a stimulatory effect measured on lymphoproliferative assays, lymphocyte subset distribution, and IL-2 receptor expression. Moreover, thymic atrophy was almost completely prevented in TP5 treated animals. Of major interest, a significant delay in the appearance and growth of tumors was observed in TP5 treated rats. When DMBA-treated animals were followed for the entire observation period (0-120 days) and the immune responsiveness correlated according to tumor progression, stability, or regression, a positive correlation was calculated between the degree of immune system depression and the individual rate of tumor growth; in TP5-treated rats the majority of the tumors were static or regressing tumors.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:The immune system response during development and progression of carcinogen-induced rat mammary tumors: prevention of tumor growth and restoration of immune system responsiveness by thymopentin. 831 80

Human T-cell leukemia virus type I (HTLV-I) is recognized as the etiologic agent of adult T-cell leukemia (ATL), a disease endemic in certain regions of southeastern Japan, Africa, and the Caribbean basin. Although HTLV-I can immortalize T lymphocytes in culture, factors leading to tumor progression after HTLV-I infection remain elusive. Previous attempts to propagate the ATL tumor cells in animals have been unsuccessful. Severe combined immunodeficient (SCID) mice have previously been used to support the survival of human lymphoid cell populations when inoculated with human peripheral blood lymphocytes (PBL). SCID mice were injected intraperitoneally with PBL from patients diagnosed with ATL, HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP), or from asymptomatic HTLV-I-seropositive patients. Many of these mice become persistently infected with HTLV-I. Furthermore, after human reconstitution was established in these mice, HTLV-I-infected cells displayed a proliferative advantage over uninfected human cells. Lymphoblastic lymphomas of human origin developed in animals injected with PBL from two ATL patients. The tumor cells represented outgrowth of the original ATL leukemic clone in that they had monoclonal or oligoclonal integrations of the HTLV-I provirus identical to the leukemic clone and predominantly expressed the cell surface markers, CD4 and CD25. In contrast, cell lines derived by HTLV immortalization of T cells in vitro did not persist or form tumors when inoculated into SCID mice, indicating differences between in vitro immortalized cells and ATL leukemic cells. This system represents the first small animal model to study HTLV-I tumorigenesis in vivo.
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PMID:Establishment of human T-cell leukemia virus type I T-cell lymphomas in severe combined immunodeficient mice. 833 42

To assess safety, antitumor response, and immunological and virological activity of interferon-alpha 2a and zidovudine combination therapy in patients with AIDS-related Kaposi's sarcoma, we conducted an open-label, Phase II, multicenter study. Sixty-three patients with biopsy-proven Kaposi's sarcoma and no previous interferon-alpha therapy received zidovudine 600 mg/day and interferon-alpha 2a 18 x 10(6) U/day. The median duration of follow-up was 49 weeks. Of 62 evaluable patients, 25 (40%; 95% confidence interval, 0.28-0.52) showed a complete (26%) or partial (15%) antitumor response. Eight of 30 patients (27%) with < 100 CD4 cells/mm3 and 17 of 32 patients (53%) with > or = 100 CD4 cells/mm3 had a response. The median time to response was 36 weeks. Of the 25 patients with a response, four developed tumor progression. The median duration of response was 22.4 weeks. Eight patients (13%) developed another AIDS-defining event and 13 (21%) died. The major toxicities included anemia (16%), neutropenia (27%), elevated serum transaminases (16%), weight loss (16%), malaise (14%), fatigue (14%), fever (10%), and headache (6%). Therapy with intermediate-dose interferon-alpha 2a and zidovudine resulted in tumor regression in patients with AIDS-related Kaposi's sarcoma who had a wide range of CD4 cell counts; this therapy was relatively well tolerated.
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PMID:A phase II study of recombinant human interferon-alpha 2a and zidovudine in patients with AIDS-related Kaposi's sarcoma. AIDS Clinical Trials Group. 860 Dec 24

The priming of tumor-antigen-specific T cells is critical for the initiation of successful anti-tumor immune responses, yet the fate of such cells during tumor progression is unknown. Naive CD4(+) T cells specific for an antigen expressed by tumor cells were transferred into tumor-bearing mice. Transient clonal expansion occurred early after transfer, accompanied by phenotypic changes associated with antigen recognition. Nevertheless, these cells had a diminished response to peptide antigen in vitro and were unable to be primed in vivo. The development of antigen-specific T cell anergy is an early event in the tumor-bearing host, and it suggests that tolerance to tumor antigens may impose a significant barrier to therapeutic vaccination.
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PMID:Induction of antigen-specific T cell anergy: An early event in the course of tumor progression. 944 5

A glycoprotein extract (CVS), derived from the unicellular green alga Chlorella vulgaris, strain CK22, exhibited a pronounced antitumor effect against both spontaneous and experimentally induced metastasis in mice. Inhibition of tumor metastasis was enhanced when intratumor administration of CVS was followed by s.c. injection of CVS. Anti-metastatic immunopotentiation was observed in euthymic mice, but not in athymic nude mice. The antitumor activity of CVS was reflected in antigen-specific, T-cell-mediated immunity. Both CD4 and CD8 T cells contributed to the antimetastatic effects, as shown by in vivo depletion experiments with anti-T-cell subset antibodies. Furthermore, CVS caused the recruitment of T cells to the regional lymph nodes and their proliferation in these organs. The CD4-positive population, following CVS injection at the time of tumor rechallenge, displayed a pronounced increase in the proportion of T cells that were CD18 bright, CD44 bright, CD25+, CD54+, CD69+ or CD71+ in the lymph nodes. Thus, CVS induces T cell activation in peripheral lymph nodes in tumor-bearing mice. We conclude that CVS augments antimetastatic immunity through T cell activation in lymphoid organs and enhances recruitment of these cells to the tumor sites. Presurgical treatment with CVS might prevent metastasis or tumor progression.
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PMID:A novel glycoprotein obtained from Chlorella vulgaris strain CK22 shows antimetastatic immunopotentiation. 949 Feb 1

Anti-idiotypic antibodies are a new type of useful tools for the possible treatment of cancer patients, since some act as antigen specific immunomodulators. Anti-idiotypic monoclonal antibody (anti-Id MAb) D704 (Ab2) was established which bore the internal image of the determinant defined by MAb M2590 (Ab1) against a sialic acid residue on GM3 ganglioside. In an in vivo syngeneic tumor system, anti-Id MAb D704 was more effective in preventing tumor progression, as compared with anti-GM3 MAb or no treatment. Significant suppression of tumor growth and prolongation of survival by administration of anti-Id MAb D704 in an animal group inoculated with 1 x 10(4)/mouse melanoma cells were seen, but not in a group inoculated with 5 x 10(4) cells/mouse. In an active specific immunotherapy protocol utilizing Ab2, the activity of anti-anti-Id antibodies (Ab3) specific for GM3 (antigen) which has a weak immunogenicity only, was maintained for more than 3 months. Ab2 generated cellular anti-tumor immune responses, including delayed type hypersensitivity (DTH) reaction. Immunohistological analysis indicated a marked infiltration of CD4 and CD8 positive cells into the DTH sites. Our results suggest that internal image bearing anti-Id MAbs have a therapeutic potential against tumors if the number of melanoma cells is relatively low or if hosts are at an early stage of melanoma progression.
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PMID:Anti-tumor effect of internal image bearing anti-idiotypic monoclonal antibody in relation to GM3 ganglioside. 957 71

Lymphocytopenia is a prognostic factor for shorter survival in advanced lung cancer and it is likely related to an interleukin-2 (IL-2) deficiency occurring during cancer progression. Major surgery itself for cancer is known to induce lymphocytopenia in the postoperative period. Postoperative lymphocyte decrease in colorectal cancer can be prevented by preoperative administration of recombinant human (rhIL-2), indicating that it is possible to drive appropriately important host defence agents during critical events, such as major surgery. The aim of this study is to verify if recombinant human interleukin-2 (rhIL-2) administered preoperatively is able to prevent the lymphocyte decrease occurring after radical surgery in operable lung cancer. This phase II study included 40 patients with operable NSCLC screened as stage II or IIIA, randomized to receive rhIL-2, 9000000 IU subcutaneously twice daily for 3 days before surgery (treated group, 20 patients) or not (control group, 20 patients). At baseline, there were no significant differences in total lymphocyte number and lymphocyte subsets (T-cell, T-helper, CD8+, natural killer, CD4/CD8 ratio) between groups. Postoperatively the control group showed a decrease in total lymphocyte count, T-lymphocyte count, T-helper cell number and CD4/CD8 ratio, significant at the 14th postoperative day relative to baseline values. In contrast, in the rhIL-2 treated group, at the 3rd and at the 14th postoperative days, a significant increase was observed over both baseline and control group values of total lymphocyte count, T-cells and T-helper cells. NK cell number increased significantly only over the control group. CD4/CD8 ratio was increased at the 14th postoperative day significantly over both baseline and control values. At pathological staging after surgery, four patients in the rhIL-2 group and four in the control group resulted in stage pIIIB; one patient in the rhIL-2 group resulted in stage IV (contralateral metastasis). Indeed, 15/20 rhIL-2 treated patients and 16/20 control patients were radically operated. After a 24-month follow-up, 12/20 rhIL-2 treated patients were alive and 8/15 radically operated were disease-free; 8/20 control patients were alive and 4/16 radically operated were disease-free. Toxicity was mild to moderate and easy manageable; treatment was suspended in one patient due to skin rash with hypotension grade II. The preoperative administration of rhIL-2 is feasible and prevents lymphocyte decrease occurring postoperatively after surgery for lung cancer. Further studies are required to assess the impact on survival.
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PMID:Phase-II randomized study of pre-operative IL-2 administration in operable NSCLC. 973 54

Granzyme B (GrB) and T-cell-restricted intracellular antigen (TIA-1) are cytotoxic proteins that are specifically expressed by cytotoxic CD4 or CD8 positive T cells and natural killer cells. Recent studies demonstrated frequent expression of GrB and TIA-1 by neoplastic cells in primary cutaneous CD30(+) large T-cell lymphomas and lymphomatoid papulosis but not in CD30(-) large T-cell lymphomas. In the present study, 74 biopsies from 54 patients with mycosis fungoides (MF) were investigated for the expression of GrB and TIA-1 using immunohistochemistry on paraffin sections. Staining of more than 10% of the neoplastic T cells for GrB or TIA-1 was considered positive. All but two follow-up biopsies had been obtained from patients without extracutaneous disease at the time of biopsy. Expression of TIA-1 and GrB was found in 33 (45%) and 14 (19%) of 74 MF biopsies, respectively. Comparison of biopsies from T3NoMo-stage MF (n = 27) and T2NoMo-stage MF (n = 45) showed increased expression of TIA-1 (55 versus 37%) and GrB (33 versus 9%) in T3NoMo-stage MF. Evaluation of multiple sequential biopsies from successive stages of MF also revealed an increase in the GrB/TIA-1 expression with tumor progression in five of eight cases. A clearcut relation between the expression of TIA-1 and/or GrB and the type of skin lesion biopsied was found. Considering all 74 biopsies, expression of TIA-1 and GrB was found in 18 of 50 (35%) and 5 of 50 (10%) patches or plaques, 9 of 16 (55%) and 3 of 16 (20%) tumors without blastic transformation, and 6 of 8 (75%) and 6 of 8 (75%) tumors with blastic transformation (defined as >50% blast cells). Correlation between GrB/TIA-1 expression in first diagnostic biopsies from patches or plaques from 40 patients with T2NoMo-stage MF and clinical follow-up data did not reveal differences in clinical behavior and survival between patients with (n = 14) or without (n = 26) expression of cytotoxic proteins, indicating that MF expressing cytotoxic proteins should not be considered as a separate group.
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PMID:Expression of cytotoxic proteins by neoplastic T cells in mycosis fungoides increases with progression from plaque stage to tumor stage disease. 1023 58

Multiple myelomas produce tumor-specific antigen (TSA) in the form of idiotype (Id) on monoclonal Ig. CD4(+) T cells can recognize Id-peptide on MHC class II molecules and protect against challenges with MOPC315 cells, which are, as common for myelomas, class II-negative. The present study explains these previous results by demonstrating that Id can be transferred from myeloma cells to antigen-presenting cells (APC), which present processed Id-peptide on their class II molecules to Id-specific T cell receptor-transgenic (TCR-TG) CD4(+) T cells. Id-primed tumor APC were heterogeneous, the majority being dendritic cells with class II(+), CD11b(+) CD11c(+) CD40(+) CD80(+) CD86(+) markers. The APC were localized beneath CD31(+) endothelial cells of tumor microvessels, and their frequency declined with tumor progression. The APC could stimulate Id-specific naive TCR-TG, short-term polarized TCR-TG, and cloned CD4(+) T cells to proliferate and produce cytokines in vitro. Furthermore, small MOPC315 tumors established in Id-specific TCR-TG mice contained clusters of activated (CD69(+)CD25(+)) and proliferating (BrdUrd(+)) Id-specific transgenic CD4(+) blasts. The activated Id-specific T cells were located adjacent to Id-primed dendritic cells in the tumor. Thus, a TSA can be transferred in vivo from myeloma, and possibly other types of cancer cells to APC for MHC class II presentation to CD4(+) T cells.
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PMID:Dendritic cells purified from myeloma are primed with tumor-specific antigen (idiotype) and activate CD4+ T cells. 1070 28

The effectiveness of cell-mediated immunotherapy for cancer can be limited by loss-of-antigen mutations that occur during tumor growth. In neuroblastoma, amplification of the MYCN oncogene correlates with rapid tumor progression and a poor prognosis overall. We propose that the MYCN protein, the high-level expression of which is required for maintenance of the malignant phenotype, would be an ideal target for vaccine therapy. The MYCN-derived S9K peptide (amino acids 7-15; STMPGMICK), which contains an HLA-A1 binding motif, was used to generate CTLs from the peripheral blood lymphocytes of an HLA-A1+ healthy donor and an HLA-A1+ patient with MYCN-amplified neuroblastoma These CTL lines specifically lysed HLA-matched, MYCN-amplified neuroblastoma tumor cells. They did not lyse either HLA-mismatched, MYCN-amplified, or matched/nonmatched, non-MYCN-amplified tumor cells. The CTL activity was inhibited by a monoclonal antibody to a class I HLA monomorphic determinant but not by one specific for HLA class II, consistent with a class I-restricted mechanism of cytotoxicity. Antibodies to CD8, but not those to CD4, also inhibited CTL activity, identifying CD8+ lymphocytes as the effector cell population. These results show that MYCN-derived peptides can serve as tumor-specific antigens and suggest a rational approach to cell-mediated immunotherapy for MYCN-amplified neuroblastoma.
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PMID:Lysis of MYCN-amplified neuroblastoma cells by MYCN peptide-specific cytotoxic T lymphocytes. 1076 79


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