Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0598934 (tumor growth)
 58,965 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Whereas the standard immunosuppressive agents foster development of posttransplant lymphoproliferative disorders (PTLDs), the impact of RAD, a macrolide with potent immunosuppressive properties, and other immunosuppressive macrolides on these disorders remains undetermined. We found that RAD had a profound inhibitory effect on in vitro growth of six different PTLD-like Epstein-Barr virus+ lymphoblastoid B cell lines. Similar to normal T cells, RAD blocked cell-cycle progression in PTLD-like B cells in the early (G(0)/G(1)) phase. Furthermore, RAD increased the apoptotic rate in such cells. The drug also had a profound inhibitory effect on the growth of PTLD-like Epstein-Barr virus+ B cells xenotransplanted s.c. into SCID mice. The degree of the RAD effect varied among the three B cell lines tested and was proportional to its effects on the cell lines in vitro. In this in vivo xenotransplant model, RAD markedly delayed growth or induced regression of the established tumors. In one line, it was able to eradicate the tumor in four of eight mice. When RAD treatment was initiated before tumor cell injection, a marked inhibition of tumor growth was seen in all three lines. In two of them, the drug prevented tumor establishment in approximately 50% of mice (5/11 and 5/8). In summary, RAD is a potent inhibitor of PTLD-like cells in vitro and in vivo. These findings indicate that, in contrast to the standard immunosuppressive agents, macrolides such as RAD may be effective in prevention and treatment of PTLDs.
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PMID:The immunosuppressive macrolide RAD inhibits growth of human Epstein-Barr virus-transformed B lymphocytes in vitro and in vivo: A potential approach to prevention and treatment of posttransplant lymphoproliferative disorders. 1075 64

Interleukin 12 (IL-12) is a heterodimeric cytokine that exerts a potent antitumor effect through its pleiotropic actions. It was recently reported that IL-12 has also a potent antiangiogenic effect through the induction of IFN-gamma, which triggers the production of chemokines such as IP-10 that has been shown to have antiangiogenesis properties. In this study we transfected the IL-12 gene into a human pancreatic adenocarcinoma cell line (PK-1). PK-1 cells transfected with the green fluorescence protein (gfp) gene were used as positive controls. The in vitro growth curve and in vivo tumor growth of transfectants (IL-12/PK-1 and gfp/PK-1) were compared with those of parental cells. The SCID mice used in this study were administered antiasialo GM-1 Ab (100 microg, i.p., twice weekly) to deplete the remaining immunoeffector cells, NK cells. Using a skinfold chamber model, we observed and recorded tumor angiogenesis by intravital microscopy. In vitro growth of IL-12/PK-1 and gfp/PK-1 cells was not different from that of wild-type PK-1 cells (wt/PK-1). However, IL-12 transfected PK-1 cells did not develop into tumors as did the wt/PK-1 cells after subcutaneous inoculation in antiasialo GM-1 Ab administered SCID mice. The growth of IL-12/PK-1 tumors was restored in mice treated with anti-IL-12 antibody. We found that IL-12/PK-1, in contrast to gfp/PK-1 and wt/PK-1, failed to initiate an angiogenic response, as observed in the skinfold chamber model. These results indicate that the antiangiogenesis effect of IL-12 alone, without immune system involvement, is sufficient to block the growth of human pancreatic cancer.
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PMID:The antiangiogenesis effect of interleukin 12 during early growth of human pancreatic cancer in SCID mice. 1076 47

The relationship between spontaneous apoptosis and overexpression of manganese superoxide dismutase (MnSOD) gene was examined in vivo. The mouse fibrosarcoma cells expressing high MnSOD activities due to transfection with the human MnSOD cDNA (SOD-H), or the fibrosarcoma cells transfected with the selectable marker alone (NEO), were transplanted into immune-deficient Fox Chase SCID C.B-17/Icr-scid Jcl mice. Apoptosis in tumors was visually quantified by the in situ end-labeling method. The number of apoptotic cells in the SOD-H tumors was significantly less than that in the NEO tumors. The tumor growth time of the SOD-H tumors to grow from 34 to 500 mm3 in one-half of the mice was slightly longer than that of the NEO tumors, but the difference was not statistically significant. These results suggest that overexpression of MnSOD gene is involved in the suppression of spontaneous apoptosis, without a resultant alteration in the tumor growth.
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PMID:Overexpression of manganese superoxide dismutase gene suppresses spontaneous apoptosis without a resultant alteration in in vivo growth of the mouse fibrosarcoma, FSa-II. 1076 28

Secondary lymphoid tissue chemokine (SLC, also referred to as Exodus 2 or 6Ckine) is a recently identified high endothelial-derived CC chemokine. The ability of SLC to chemoattract both Th1 lymphocytes and dendritic cells formed the rationale to evaluate this chemokine in cancer immunotherapy. Intratumoral injection of recombinant SLC evidenced potent antitumor responses and led to complete tumor eradication in 40% of treated mice. SLC-mediated antitumor responses were lymphocyte dependent as evidenced by the fact that this therapy did not alter tumor growth in SCID mice. Studies performed in CD4 and CD8 knockout mice also revealed a requirement for both CD4 and CD8 lymphocyte subsets for SLC-mediated tumor regression. In immunocompetent mice, intratumoral SLC injection led to a significant increase in CD4 and CD8 T lymphocytes and dendritic cells, infiltrating both the tumor and the draining lymph nodes. These cell infiltrates were accompanied by the enhanced elaboration of Th1 cytokines and chemokines monokine induced by IFN-gamma and IFN-gamma-inducible protein 10 but a concomitant decrease in immunosuppressive cytokines at the tumor site. In response to irradiated autologous tumor, splenic and lymph node-derived cells from SLC-treated tumor-bearing mice secreted significantly more IFN-gamma, GM-CSF, and IL-12 and reduced levels of IL-10 than did diluent-treated tumor-bearing mice. After stimulation with irradiated autologous tumor, lymph node-derived lymphocytes from SLC-treated tumor-bearing mice demonstrated enhanced cytolytic capacity, suggesting the generation of systemic immune responses. These findings provide a strong rationale for further evaluation of SLC in tumor immunity and its use in cancer immunotherapy.
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PMID:Secondary lymphoid tissue chemokine mediates T cell-dependent antitumor responses in vivo. 1077 57

A monoclonal antibody specific for the human analog of the murine T-cell activation molecule 4-1BB was generated and is shown here to react selectively with activated human CD4+ and CD8+ T lymphocytes. Treatment of these T cells in a one-way mixed lymphocyte culture with the anti-h4-1BB antibody enhanced the cell proliferation of the allostimulated lymphocytes. Previous studies in the mouse have shown that treatment of tumor-bearing mice with antibodies to 4-1BB augments anti-tumor immunity that is mediated by both CD4+ and CD8+ T cells. The authors consider the possibility that a similar approach may be efficacious for human cancer immunotherapy. This question was addressed by evaluating the effect of an anti-h4-1BB monoclonal antibody on human lymphocyte-mediated suppression of a human tumor xenograft in SCID mice. Mice treated with a control antibody and co-injected with the tumor and peripheral blood lymphocytes exhibited a lymphocyte dose-dependent suppression of tumor growth. In mice treated with the anti-h4-1BB antibody, the lymphocyte-mediated tumor suppression was completely eliminated and tumors grew progressively (as was observed in mice inoculated with tumors without lymphocytes). This monoclonal antibody specific for anti-h4-1BB, which augments the proliferation of allostimulated cells in vitro, blocks T-cell anti-tumor activity in vivo. These results suggest that although 4-1BB plays a role in the human peripheral blood lymphocyte-mediated suppression of tumor growth, antibodies to this molecule on human cells fail to stimulate anti-tumor activity, as was observed in tumor-bearing mice treated with an antibody to murine 4-1BB.
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PMID:Monoclonal antibodies directed against the T-cell activation molecule CD137 (interleukin-A or 4-1BB) block human lymphocyte-mediated suppression of tumor xenografts in severe combined immunodeficient mice. 1083 65

In this study, we show that Delta-9-tetrahydrocannabinol (THC), the major psychoactive component of marijuana, suppresses host immune reactivity against lung cancer. In two different weakly immunogenic murine lung cancer models, intermittent administration of THC (5 mg/kg, four times/wk i.p. for 4 wk) led to accelerated growth of tumor implants compared with treatment with diluent alone. In contrast to our findings in immunocompetent mice, THC did not affect tumor growth in tumor-bearing SCID mice. The immune inhibitory cytokines, IL-10 and TGF-beta, were augmented, while IFN-gamma was down-regulated at both the tumor site and in the spleens of THC-treated mice. Administration of either anti-IL-10- or anti-TGF-beta-neutralizing Abs prevented the THC-induced enhancement in tumor growth. Both APC and T cells from THC-treated mice showed limited capacities to generate alloreactivity. Furthermore, lymphocytes from THC-treated mice transferred the effect to normal mice, resulting in accelerated tumor growth similar to that seen in the THC-treated mice. THC decreased tumor immunogenicity, as indicated by the limited capacity for tumor-immunized, THC-treated mice to withstand tumor rechallenge. In vivo administration of a specific antagonist of the CB2 cannabinoid receptor also blocked the effects of THC. Our findings suggest the THC promotes tumor growth by inhibiting antitumor immunity by a CB2 receptor-mediated, cytokine-dependent pathway.
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PMID:Delta-9-tetrahydrocannabinol inhibits antitumor immunity by a CB2 receptor-mediated, cytokine-dependent pathway. 1086 Oct 74

Apoptosis-inducing nucleosides (AINs) released from CD57( +) HLA-DR(bright) natural suppressor (57.DR-NS) cell line, derived from human decidual tissue, were isolated from 57.DR-NS cell culture supernatant by the combination of thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC). Apoptotic cell death was strongly induced in human T cell leukemia Molt4 cells treated with AINs, absolutely depending on DNA strand breaks, with activation of the caspase cascade, especially caspase-3. The administration of AINs to Molt4 tumor-bearing severe combined immunodeficiency (SCID) mice resulted in drastic suppression of tumor growth, with a decrease of tumor size and the appearance of apoptotic signals in tumor tissue. Thus, AINs are candidates for development as anticancer agents.
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PMID:Human T cell leukemia cell death by apoptosis-inducing nucleosides from CD57(+) HLA-DR(bright) natural suppressor cell line. 1087 16

Neoplastic progression is a prolonged and stepwise process, while tumor growth occurs after a series of molecular alterations that culminate in tumorigenesis. The phenotypic changes of transformation in breast carcinogenesis were studied through the use of scanning and transmission electron microscopy. MCF 10F, a spontaneously immortalized human breast epithelial cell line (Soule et al., 1990), was treated with 7,12 dimethylbenz(a)anthracene (DMBA) (Calaf and Russo, 1993) and then transfected with the c-Ha-ras oncogene (Calaf et al., 1995). Treated cells showed a progression in altered morphology, anchorage independency, invasiveness and tumorigenicity in the SCID. Scanning and transmission electron microscopy illustrated that the transformed cells could be distinguished from control cells by the expression of morphological characteristics such as loss of contact inhibition, irregular size and shape, emission of long filopodia and formation of stratified layers. In contrast, control cells showed uniform, flattened and polyhedrical cells, well closely juxtaposed to each other and joined by cytoplasmic interdigitations. Control cells also did not form colonies in agar-methocel, and were not invasive or tumorigenic in SCID mice. These studies showed the progression of breast carcinogenesis by phenotypical changes induced by the carcinogen and the insertion of the c-Ha-ras oncogene.
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PMID:Morphological phenotypes in neoplastic progression of human breast epithelial cells. 1087 6

Both chemotherapy and chimeric anti-CD20 monoclonal antibodies are effective agents against B-cell non-Hodgkin lymphoma (NHL). However, patients achieving remission are at risk of relapse. To evaluate the effect of the antiangiogenic drug endostatin used alone and after the administration of cyclophosphamide (CTX) or the anti-CD20 antibody rituximab, we generated a new model of human NHL by transplanting Namalwa cells intraperitoneally into nonobese diabetic/severe combined immunodeficient (NOD/SCID) mice. First, we determined the most effective treatment schedule for the drugs assessed. When administered alone, CTX (3 courses of 75 mg/kg of body weight given intraperitoneally), rituximab (3 courses of 25 mg/kg given intraperitoneally), and endostatin (5 courses of 50 microg given subcutaneously) delayed tumor growth, and CTX was the most effective in controlling bulky disease. When given after chemotherapy or immunotherapy, endostatin effectively induced tumor stabilization. When mice given CTX or rituximab on days 3, 5, and 7 after transplantation were randomly assigned to receive endostatin or phosphate-buffered saline on days 15 to 19, tumor growth was prevented in endostatin-treated mice as long as the drug was administered. Furthermore, administration of endostatin on days 25 to 29 after tumor regrowth still induced significant tumor regression, whereas CTX and rituximab were not effective. The specific antiangiogenic action of endostatin was confirmed by in vitro and in vivo studies indicating that the drug inhibited proliferation and induced apoptosis of endothelial (but not of NHL) cells. In conclusion, sequential administration of chemotherapy and endostatin seems promising for treating bulky NHL, and the less toxic sequential administration of rituximab and endostatin is promising for treating limited disease. (
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PMID:Endostatin, an antiangiogenic drug, induces tumor stabilization after chemotherapy or anti-CD20 therapy in a NOD/SCID mouse model of human high-grade non-Hodgkin lymphoma. 1089 63

Recent reports suggest that green tea consumption may prevent or delay the growth of human cancer, possibly by impairing tumor invasion and/or by an anti-angiogenic effect. In NOD/SCID mice transplanted intraperitoneally with human non-Hodgkin's lymphoma (NHL) cell lines, Namalwa, RAP1-EIO and HS-Sultan, green tea prevented 50% of Namalwa tumors (P = 0.0017 by log-rank) and significantly inhibited RAP1-EIO and HS-Sultan tumor growth. Notably, treatment with the chemotherapy drug cyclophosphamide at the maximum tolerable dose was unable to prevent Namalwa tumor occurrence. In the three models evaluated, the frequency of apoptotic endothelial and tumor cells was significantly increased in mice given green tea compared to controls. These results support further trials in NHL to evaluate whether green tea, alone or in combination with chemotherapy, may delay or prevent disease progression.
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PMID:Inhibition of angiogenesis and induction of endothelial and tumor cell apoptosis by green tea in animal models of human high-grade non-Hodgkin's lymphoma. 1094 45


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