Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

---

Query: UMLS:C0178874 (tumor progression)
40,807 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The role of nitric oxide (NO) in tumor biology remains controversial and poorly understood. While a few reports indicate that the presence of NO in tumor cells or their micro-environment is detrimental for tumor-cell survival, and consequently their metastatic ability, a large body of data suggests that NO promotes tumor progression. The purpose of this study was to identify the source of NO in the spontaneously metastasizing C3-L5 murine mammary-adenocarcinoma model, the role of tumor-derived NO in tumor-cell invasiveness, and the mechanisms underlying the invasion-stimulating effects of tumor-derived NO. The source of NO was established by immunocytochemical localization of NO synthase (NOS) enzymes in C3-L5 cells in vitro and transplanted tumors in vivo. An in vitro transwell Matrigel invasion assay was used to test the invasiveness of C3-L5 cells in the presence or the absence of NO blocking agents or iNOS inducers (IFN-gamma and LPS). The mechanisms underlying the invasion-stimulating effects of tumor-derived NO were examined by measuring mRNA expression of matrix metalloproteinases (MMP)-2 and -9, and tissue inhibitors of metalloproteinases (TIMP) 1, 2 and 3 in C3-L5 cells in various experimental conditions. Results showed that C3-L5 cells expressed high level of eNOS protein in vitro, and in vivo, both in primary and in metastatic tumors. C3-L5 cells also expressed iNOS mRNA and protein when cultured in the presence of IFN-gamma and LPS. Constitutively produced NO promoted tumor-cell invasiveness in vitro by down-regulating TIMP 2 and TIMP 3. In addition, there was up-regulation of MMP-2, when extra NO was induced by IFN-gamma and LPS. In conclusion, NO produced by C3-L5 cells promoted tumor-cell invasiveness by altering the balance between MMP-2 and its inhibitors TIMP-2 and 3. Thus, our earlier observations of anti-tumor and anti-metastatic effects of NO inhibitors in vivo in this tumor model can be explained, at least in part, by reduced tumor-cell invasiveness.
...
PMID:Nitric-oxide production by murine mammary adenocarcinoma cells promotes tumor-cell invasiveness. 1036 35

The role of Fas in the regulation of solid tumor growth was investigated. Murine renal carcinoma (Renca) cells were constitutively resistant to Fas-mediated killing in vitro, but exhibited increased expression of Fas and sensitivity to Fas-mediated killing after exposure to IFN-gamma and TNF. Transfected Renca cells overexpressing Fas were efficiently killed in vitro upon exposure to anti-Fas Ab (Jo2). When Fas-overexpressing Renca cells were injected into syngenic BALB/c mice, there was a consistent and significant delay in tumor progression, reduced metastasis, and prolonged survival that was not observed for Renca cells that overexpressed a truncated nonfunctional Fas receptor. The delay of in vivo tumor growth induced by Fas overexpression was not observed in IFN-gamma-/- mice, indicating that IFN-gamma is required for the delay of in vivo tumor growth. However, there was a significant increase of infiltrated T cells and in vivo apoptosis in Fas-overexpressing Renca tumors, and Fas-overexpressing Renca cells were also efficiently killed in vitro by T cells. In addition, a strong therapeutic effect was observed on Fas-overexpressing tumor cells by in vivo administration of anti-Fas Ab, confirming that overexpressed Fas provides a functional target in vivo for Fas-specific ligands. Therefore, our findings demonstrate that Fas overexpression on solid tumor cells can delay tumor growth and provides a rationale for therapeutic manipulation of Fas expression as a means of inducing tumor regression in vivo.
...
PMID:IFN-gamma-dependent delay of in vivo tumor progression by Fas overexpression on murine renal cancer cells. 1060 16

To investigate the cooperative effect of B7-1 and IL-12 in the induction of antitumor activity, we have developed retroviral vectors encoding human B7-1, murine IL-12, or both B7-1 and IL-12 coordinately. Murine transformed liver cells (BNL) were engineered to stably express B7-1, IL-12, or both by infection with corresponding retroviruses. No tumor was observed in 20, 75, and 95% of mice receiving, respectively, B7-1-, IL-12-, and B7-1/IL-12-modified tumor cells after 250 days of inoculation. In contrast, injection of parental BNL or BNL/Neo cells resulted in lethal tumor progression in all mice. Protection against rechallenge with parental tumor cells was observed only in mice who had rejected BNL/IL-12, but not in animals that rejected BNL/B7-1 or BNL/B7-1-IL-12. Growth of parental tumor cells was significantly delayed by simultaneous injection in a distant site of irradiated tumor cells engineered to express IL-12 or both B7-1 and IL-12 but not B7-1 alone. BNL/B7-1 and BNL/B7-1-IL-12 showed similar efficacy in these experiments. Antitumor immunity induced by B7, with or without IL-12, was found to depend mainly on CD4+ T cells with a minor contribution of a non-T cell mechanism; whereas the effect of IL-12 was dependent on CD8+ T cells and on non-T cell effectors. Immunization of mice with IL-12-modified BNL cells induced secretion of a Thl pattern of cytokines while immunization with cells expressing both IL-12 and B7-1 resulted in inhibition of IFN-gamma production. Immunization with BNL/B7-1-IL-12 cells in the presence of anti-human B7-1 MAb resulted in restoration of IFN-gamma production to the levels found in animals injected with BNL/IL-12 cells. To summarize, in our model coexpression of B7-1 and IL-12 in tumor cells does not result in improved antitumoral activity as compared with expression of IL-12 alone. This may be related to the fact that B7-1 changes the mechanisms of antitumor immunity and inhibits IFN-gamma production induced by IL-12 in vivo.
...
PMID:Gene transfer to liver cancer cells of B7-1 plus interleukin 12 changes immunoeffector mechanisms and suppresses helper T cell type 1 cytokine production induced by interleukin 12 alone. 1064 45

Physiologically, B-lymphocytes are not present in the skin. Even in pathological situations they rarely occur. In contrast, primary cutaneous B-cell lymphomas (CBCL) are characterized by proliferation of B lymphocytes within the skin. This suggests the existence of a certain microenvironment supporting homing and expansion of clonal B cells. Cytokines were demonstrated to be involved in the pathogenesis of cutaneous lymphomas of T-cell origin. Cytokine expression in cutaneous B-cell lymphoma lesions, however, has not been investigated so far. Therefore, the mRNA level of several cytokines was analyzed in biopsies from 7 patients with CBCL and compared to pleomorphic T-cell lymphoma (n = 6), psoriasis (n = 9), and healthy skin (n = 7), using a competitive RT-PCR approach. An overexpression of TNF-alpha, IL-10, and IL-6 was found. Enhanced IL-8 mRNA expression was detected in 2/7 cases. The overexpression of IL-6 and IL-10 in CBCL might be of particular importance, since these cytokines are considered to support B-cell growth. Additionally, the overexpression of IL-10 may contribute to tumor progression since this immunosuppressive cytokine might be involved in downregulation of immunological tumor surveillance, in part by inhibiting type 1 cytokine formation. In fact, we did not detect IFN-gamma and IL-2 expression. Taken together, we found a cytokine pattern in CBCL lesions which might contribute to tumor B-cell growth.
...
PMID:Cytokine expression in primary cutaneous germinal center cell lymphomas. 1068 78

Thioredoxin (Trx) and Trx reductase (TrxR) are redox-active proteins that participate in multiple cellular events, including growth promotion, apoptosis, and cytoprotection. Studies on overexpression of Trx and TrxR in human cancers have indicated a role of these proteins in tumor development. In this study, we analyzed the expression of TrxR in peripheral blood cells, tumor-transformed leukemia, and melanoma cells and found, in addition to abundant plasma membrane localization, that TrxR was released from these cells. Secretory cells were observed at the single cell level using a sensitive enzyme-linked immunospot assay. The release was inducible, and physiological stimulation of human monocytes by IFN-gamma, lipopolysaccharide, and interleukin 1alpha significantly increased the number of TrxR-secreting cells (P = 0.004). Secretion of TrxR followed the classical Golgi pathway, and it was confirmed by metabolic labeling using [35S]methionine and [35S]cysteine. TrxR was also detected for the first time in fresh healthy blood donor plasma (n = 21; median concentration, 18.0 ng/ml), with biological activity as determined by insulin reduction assay. These results highlight the role of extracellular Trx and TrxR during inflammation and tumor progression. Released Trx, with its active site motif containing amino acids Cys-X-X-Cys, was recently shown to have chemoattractant properties beside its previously described antioxidant and cocytokine activities. Regeneration of oxidized Trx requires available TrxR outside the cell, the presence and induction of which is described in this paper for normal and transformed cells.
...
PMID:Thioredoxin reductase, a redox-active selenoprotein, is secreted by normal and neoplastic cells: presence in human plasma. 1078 96

The aim of this study was to examine the tolerability, antitumor activity, and biological effects of a new schedule of i.v. recombinant human interleukin 12 (rhIL-12). Twenty-eight patients were enrolled in a Phase I trial in which rhIL-12 was administered twice weekly as an i.v. bolus for 6 weeks. Stable or responding patients were eligible to receive additional 6-week cycles until there was no evidence of disease or until tumor progression. Patient cohorts were treated with escalating doses of rhIL-12 (30-700 ng/kg). The maximum tolerated dose (MTD) was 500 ng/kg, with dose-limiting toxicities consisting of elevated hepatic transaminases and cytopenias. At the MTD (n = 14), there was one partial response occurring after 6 cycles of rhIL-12 in a patient with renal cell cancer. Two additional renal cell cancer patients treated at the MTD had prolonged disease stabilization, with one of these exhibiting tumor regression after 8 cycles of rhIL-12. IFN-gamma, IL-15, and IL-18 were induced in patients treated with rhIL-12. Whereas IFN-gamma and IL-15 induction were attenuated midway through the first cycle in patients with disease progression, those patients with tumor regression or prolonged disease stabilization were able to maintain IFN-gamma, IL-15, and IL-18 induction. The down-modulation of IFN-gamma induction during rhIL-12 treatment did not relate to IL-10 production or alterations in rhIL-12 bioavailability but was associated with an acquired defect in lymphocyte IFN-gamma production in response to IL-12, IL-2, or IL-15. This defect could be partially overcome in vitro through combined stimulation with IL-12 plus IL-2. These findings show that the chronic administration of twice-weekly i.v. rhIL-12 is well-tolerated, stimulates the production of IL-12 costimulatory cytokines and IFN-gamma, and can induce delayed tumor regression. Strategies aimed at maintaining IFN-gamma induction, such as the addition of IL-2, may further augment the response rate to this schedule of rhIL-12.
...
PMID:Phase I trial of twice-weekly intravenous interleukin 12 in patients with metastatic renal cell cancer or malignant melanoma: ability to maintain IFN-gamma induction is associated with clinical response. 1081 86

The relationship between nitric oxide (NO) synthase II (NOS II) expression and the metastatic ability of tumor cells is inconclusive. We determined the role of host NOS II expression in the growth and metastasis of the B16-BL6 murine melanoma and M5076 murine ovarian sarcoma cell lines. The cells were either s.c. or i.v. injected into syngeneic wild-type (NOS H+/+) and NOS II-null (NOS H-/-) C57BL/6 mice. Both cell lines produced slightly larger s.c. tumors in NOS H-/- mice than in NOS II+/+ mice. However, B16- BL6 cells produced more and larger experimental lung metastases in NOS II+/+ mice than in NOS II-/- mice, whereas M5076 cells produced fewer and smaller experimental lung metastases in NOS II+/+ mice than in NOS II-/- mice. After activation with IFN-gamma and lipopolysaccharide, macrophages isolated from NOS II+/+ C57BL/6 mice produced NO-dependent cytotoxicity in sarcoma cells, whereas macrophages from NOS II-/- C57BL/6 mice did not. In contrast, activated macrophages produced little to no NO-mediated cytotoxicity in melanoma cells. Immunostaining analyses indicated that NOS II expression was apparent in the metastases growing in NOS H+/+ mice and correlated with increased cell proliferation in B16-BL6 lung metastases but with decreased cell proliferation in M5076 liver metastases. Our data suggest that disruption of host NOS II expression enhanced the growth and metastasis of NO-sensitive tumor cells but suppressed the metastasis of NO-resistant tumor cells, proposing that host-derived NO may differentially modulate tumor progression.
...
PMID:Influence of nitric oxide synthase II gene disruption on tumor growth and metastasis. 1082 24

Using a novel transgenic mouse model of spontaneous mammary carcinoma, we show here that the IL-12/pulse IL-2 combination can induce rapid and complete regression of well-established autochthonous tumor in a setting where the host immune system has been conditioned by the full dynamic process of neoplastic progression and tumorigenesis. Further, this regimen inhibits neovascularization of established mammary tumors, and does so in conjunction with potent local induction of genes encoding the IFN-gamma- and TNF-alpha-inducible antiangiogenic chemokines IFN-inducible protein 10 and monokine induced by IFN-gamma. In contrast to untreated juvenile C3(1)TAg mice in which histologically normal mammary epithelium predictably undergoes progressive hyperplasia, atypical changes, and ultimately transition to overt carcinoma, the current studies also demonstrate a unique preventative therapeutic role for IL-12/pulse IL-2. In juvenile mice, early administration of IL-12/pulse IL-2 markedly limits the expected genetically programmed neoplastic transition within the mammary epithelium and does so in conjunction with enhancement of constitutive Fas and pronounced induction of local Fas ligand gene expression, T cell infiltration, and induction of apoptosis within the mammary epithelium. These events occur in the absence of a durable Ag-specific memory response. Thus, this novel model system demonstrates that the potent therapeutic activity of the IL-12/pulse IL-2 combination rapidly engages potent apoptotic and antiangiogenic mechanisms that remain active during the delivery of IL-12/pulse IL-2. The results also demonstrate that these mechanisms are active against established tumor as well as developing preneoplastic lesions.
...
PMID:Complete regression of established spontaneous mammary carcinoma and the therapeutic prevention of genetically programmed neoplastic transition by IL-12/pulse IL-2: induction of local T cell infiltration, Fas/Fas ligand gene expression, and mammary epithelial apoptosis. 1114 97

A 49-year-old patient with primary, recurrent melanoma on the lower extremity developed metastatic leptomeningeal melanoma that did not respond to treatment with radiation therapy or intrathecal interleukin 2 (IL-2). Disease was characterized by neurological symptoms, including loss of hearing, loss of short-term memory, and gait disturbance. CD8+ CTLs were generated in vitro using autologous dendritic cells pulsed with peptides from the melanoma-associated antigens tyrosinase (145-156), Melan-A/MART-1 (26-35), and gp100/Pmel 17 (209-217). The CTLs exhibited up to 74% specific lysis against peptide-pulsed autologous EBV-transformed B cells, with Melan-A-specific CTLs yielding the greatest lytic activity. CD8+ CTLs possessed a type 1 cytokine profile, expressing tumor necrosis factor alpha and IFNgamma but not IL-4. Infusions of CTLs were supported with systemic low-dose IL-2 administration. 111In labeling and computerized gamma imaging were used to monitor the distribution of CTLs up to 48 h after infusion. Intra-arterial delivery via the right carotid artery was followed by redistribution of the CTLs to the lungs, liver, and spleen within 16 h. In contrast, delivery via an indwelling Ommaya reservoir resulted in prolonged retention of CTLs within the brain for at least 48 h after infusion. Marked but transient elevations in tumor necrosis factor alpha, IFN-gamma, and IL-6 in the cerebrospinal fluid were observed within 4 h of CTL infusion. There was no evidence of tumor progression throughout the treatment period, and clinically the patient showed some resolution of neurological symptoms.
...
PMID:Intrathecal cytotoxic T-cell immunotherapy for metastatic leptomeningeal melanoma. 1130 Apr 92

T cells can be directed to antigen-specific, MHC-independent target cell lysis by grafting with a recombinant receptor with antibody-like specificity. Here, we asked whether T cells from the peripheral blood of a patient with cutaneous T cell lymphoma can be recruited for an immune response against autologous tumor cells. Lymphoma cells with a CD3(-) CD4(+) CD30(+) phenotype and clonal TCR-Vbeta7 rearrangement were isolated from a cutaneous lesion. The lymphoma lesion additionally harbored CD3(+) CD25(+) activated normal T cells despite ongoing tumor progression. Peripheral blood-derived T cells from the lymphoma patient were retrovirally engrafted with a recombinant anti-CD30-scFv-gamma receptor. Upon cocultivation with autologous CD30(+)lymphoma cells, grafted T cells increase IFN-gamma secretion and lyse specifically lymphoma cells with high efficiency, even at an effector to target cell ratio of as low as 1:20. Our data demonstrate that the recombinant anti-CD30-gamma receptor overcomes T cell tolerance for tumor cells and directs T cells specifically against autologous lymphoma cells.
...
PMID:T cells engrafted with a recombinant anti-CD30 receptor target autologous CD30(+) cutaneous lymphoma cells. 1142 37


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>

---