Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Incubation of C3H/Hen thymocytes in the presence of recombinant human tumor necrosis factor alpha (TNF) and interleukin-2 (IL-2) augmented the generation of antibody-dependent cellular cytotoxicity (ADCC) when compared to cells cultured in TNF or IL-2 alone. This effect was optimal when 100-200 units/ml IL-2 was used together with 10(3)-10(4) units/ml TNF. TNF alone at any concentration could not mediate the induction of ADCC. Similar to the results obtained in vitro, TNF, when given alone, had no effect on the generation of ADCC in vivo. The addition, however, of TNF to IL-2, given at 10,000 and 20,000 but not 40,000 units, enhanced the IL-2-induced ADCC on a per-cell basis. Furthermore, TNF enhanced the total ADCC activity in various organs including the liver, spleen and thymus as a result of an increase in the number of mononuclear cells isolated from these organs. The increase in total ADCC activity was optimal when 110,000-220,000 units (5-10 micrograms) TNF were employed together with IL-2. The combined treatment with TNF and IL-2 also increased the intracellular benzyloxycarbonyl-1-L-lysine-thiobenzyl-ester esterase content in cells isolated from the livers of mice treated with these cytokines. On the basis of these results we treated mice bearing a single B16 melanoma nodule with TNF and TNF + IL-2 given with or without anti-B16 monoclonal antibody. We found that TNF administration augmented the anti-tumor effect of specific anti-B16 antibodies, and the addition of IL-2 further increased this anti-tumor effect.
 ...
PMID:Effect of recombinant human tumor necrosis factor alpha on the induction of antibody-dependent cellular cytotoxicity in the treatment of established B16 melanoma liver nodules. 237 20

We have performed Phase I trials of two synthetic double-stranded polyribonucleotide complexes--poly(I,C)-LC, a complex of polyinosinic-polycytidylic acid with poly-L-lysine and carboxymethylcellulose, and poly(I,C)-L, which lacks carboxymethylcellulose--in patients with advanced cancer. With poly(I,C)-LC, several treatment schedules were investigated in an attempt to decrease toxicity and maximize interferon (IFN) induction. The best tolerated was an alternate-day schedule, with gradual dose escalation. Daily short infusions and continuous (24-h) infusions were tolerated less well. Maximum tolerated doses varied over a several hundredfold dose range. Toxicity consisted of fever, rigors, hypotension, and blood count depression. Two patients treated with poly(I,C)-L developed systemic allergic reactions, and antibodies to poly(I,C)-L and its components were detected in the serum of some patients treated with both compounds. IFN-alpha was induced in most patients at serum levels similar to those achieved after intramuscular administration of human IFN-alpha. Of 32 patients, one with renal cell carcinoma showed partial tumor regression. Poly(I,C) complexes are effective IFN inducers in humans, but their toxicity limits their use in cancer patients.
 ...
PMID:Phase I trials of poly(I,C) complexes in advanced cancer. 241 62

4-Nitro-5-sulfonylimidazoles represent a class of hypoxic cell radiation sensitizers whose in vitro activity greatly exceeds that of the current clinical standard, misonidazole. However, in vivo studies with these 4,5-disubstituted imidazoles have shown that a rapid reaction with circulating thiols decomposes the agent and compromises its clinical utility. Drug-macromolecule conjugates prepared in this study from poly-L-glutamate, succinylated poly-L-lysine, dextran, and a succinylated polylysine-antibody, all demonstrated protection of the drug from glutathione displacement. 1-Methyl-4-nitro-5-imidazolyl 4-aminophenyl sulfone conjugated to a succinylated poly-L-lysine-antibody was greater than 7 times less reactive than the unbound drug. Polymer transport may offer a useful tumor-delivery mechanism for these highly reactive radiation sensitizers.
 ...
PMID:Macromolecular attachment as a metabolic stabilizer for a labile radiosensitizer. 244 38

The heat response of five human tumor biopsies has been examined using the fluorescent probe dansyl lysine and multiparameter flow cytometry. Dansyl lysine has previously been shown to possess specificity for heat killed mammalian cells. The human tumors tested included a cervical squamous cell carcinoma, malignant melanoma, colon adenocarcinoma, ovarian carcinoma, and a mesothelioma. The samples were excised, mechanically disrupted into single cell suspensions and heated in vitro for various lengths of time at 45 degrees C. The cells were returned to 37 degrees C incubation for 12 to 15 hours prior to staining with dansyl lysine. The fraction of cells staining dansyl lysine was quantitated by flow cytometry after gating on high forward angle light scatter and 90 degrees C light scatter. This gate excluded much of the normal cell contamination within the tumor sample. The data show that the heat response of human tumor biopsies varied significantly, with cervical carcinoma and malignant melanoma being the most resistant and the mesothelioma and ovarian carcinoma the most heat sensitive. Finally, evidence is presented for the expression of thermotolerance in ovarian carcinoma and mesothelioma biopsies pre-heated in vitro. Dansyl lysine appears to be useful in measuring the intrinsic cellular heat sensitivity of human tumors and in determining the kinetics of decay of thermotolerance following an initial heat exposure.
 ...
PMID:A predictive assay for human tumor cellular response to hyperthermia using dansyl lysine staining and flow cytometry. 244 73

The fraction of cells excluding the fluorescent dye dansyl lysine has previously been shown to correlate well with heat-induced cell killing in a variety of mammalian cell lines and in murine tumors in vivo. Here we evaluate the usefulness of dansyl lysine as a probe for assessment of thermal damage and for measuring the kinetics of thermotolerance development and decay in murine normal tissues. Skin cells were heated in vivo with an initial treatment of 44 degrees C for 20 min by local radiofrequency. Bone marrow cells were heated at 42.5 degrees C for 20 min by whole body water bath immersion. Cell suspensions were prepared, heated in vitro for various lengths of time at 44 degrees C (skin) or 43 degrees C (bone marrow), and scored for the fraction of dansyl lysine-excluding cells. Skin and bone marrow cells expressed maximum thermotolerance by 8 and 6 hr, respectively and returned to normal heat sensitivity by 48 and 146 hr, respectively. The assay was not useful with skeletal muscle and liver, as we were not successful in obtaining viable, dansyl lysine-excluding cells from these tissues. Also, in our hands red blood cells, normal human leukocytes, mouse spleen and thymus cells all failed to stain dansyl lysine even after extreme heating. Dansyl lysine staining, particularly when combined with flow cytometry analysis, has been shown to be a useful method for assessing thermal damage and thermotolerance relatively rapidly in all tumor systems tested to date, and, as shown here, may possess utility in measuring similar endpoints for certain nonclonogenic normal tissues.
 ...
PMID:The use of dansyl lysine to assess heat damage and thermotolerance of normal tissues. 245 47

The effect of interferon inducing complex of polyriboinosinic, polyribocytidylic acid with poly-L-lysine and carboxymethylcellulose - Poly (ICLC) - on the response of Lewis lung carcinoma in C57B1 mice to radiation treatments was studied. Improved tumor response was obtained in mice receiving 1.5 mg/m2 or higher of Poly (ICLC). Such doses have induced more than 1000 mu/ml of serum interferon. The same doses of Poly (ICLC) potentiated the epilation effect of radiation. The injection of 0.15 mg/m2 of Poly (ICLC) led to protection of the tumor and the stimulation of it's growth. It also did not potentiate the epilation effect. In this study, one weekly administration of Poly (ICLC) was as effective as three times per week treatment. The cellular mechanism of the increased radiosensitivity caused by Poly (ICLC) was reflected in the reduction of the width of the shoulder on the cell survival curve, which was dependent on the dose of the drug. In cell cultures, doses of 100 micrograms/ml synchronized the cell division, thus contributing to the increase in radiosensitivity.
 ...
PMID:Tumor response to interferon inducer and radiation effect of serum interferon levels. 245 8

Mild proteolytic treatment of SW1116 tumor cells with trypsin or plasmin increases their plasmin-binding ability considerably by increasing the number of binding sites without altering their affinity. This mechanism may be operative for increasing the concentration of active plasmin at the surface of tumor cells. C-terminal lysine residues are involved in plasmin binding to cells, since treatment of cells with carboxypeptidase B decreases this binding by 50%.
 ...
PMID:Limited proteolysis of tumor cells increases their plasmin-binding ability. 246 97

Site-specific covalent modification of monoclonal antibodies at the oligosaccharide offers advantages over more conventional modification processes that involve direct attachment at tyrosine, lysine or glutamic/aspartic acid side chains. Using the site-specific modification process, attachment sites on the antibody are distal to the antigen-binding region. Thus, homogeneity of antigen-binding properties and affinity for the unmodified protein are preserved. Furthermore, higher derivatization ratios with no resultant loss of immunoreactivity can be achieved for monoclonal antibodies modified at the oligosaccharide. In vivo biodistribution and tumor localization studies in nude mouse models suggest that antibodies radiolabeled at their oligosaccharide might represent improved immunoscintigraphic reagents. In a variety of tumor xenograft models, site-specific modified 111In-labeled antibody conjugates localized to the tumor site with little non-specific localization in other tissues or organs. The degree of localization at the target site was substantially greater than that of 111In-labeled antibodies directly modified at the tyrosine side chain. Preliminary studies with 212Bi- and 90Y-labeled antibodies modified at the oligosaccharide indicate that both of these radioisotopes have immunotherapeutic potential. Because of its preferential uptake by the kidney, the use of 212Bi may be best suited for tumors localized within the peritoneal cavity, such as ovarian and colorectal carcinomas. The toxicity of 90Y at high specific activities suggests that a regimen of repeated smaller doses of this radioisotope is best suited for therapeutic use. Studies in tumor-bearing mouse models are currently underway to better define the optimal dosage and administration regimens for both of these radioisotopes when attached to site-specific modified antibodies.
 ...
PMID:Radioimmunoscintigraphy and radioimmunotherapy in nude mouse models. Studies with site-specifically modified monoclonal antibodies. 251 52

Thionapthene-2-carboxylic acid (TNCA) was previously shown to lower serum calcium concentrations in hypercalcemic rats: however, oral administration of TNCA may cause gastric irritation. We have assessed thionapthene-2-carboxylic acid lysine salt (TNLY) for its effects on serum calcium concentration and survival in rats bearing the hypercalcemic Leydig cell tumor. TNLY (0.6-1.8 mmol/kg/day) produced a marked and prolonged dose-related decrease in serum calcium concentration. At the highest dose of 1.8 mmol/kg/day, hypocalcemia occurred. Effects were sustained for 96 hours or longer. In tumor-bearing rats that were not yet hypercalcemic, pretreatment with TNLY (0.9 mmol/kg/day) did not induce hypocalcemia and the onset of hypercalcemia was prevented. Neither TNLY nor dichloromethylene diphosphonate (CL2MDP), a potent inhibitor of bone resorption, significantly prolonged overall survival. We concluded that TNLY is a potent antihypercalcemic agent that warrants further testing for use in the treatment of hypercalcemic disorders.
 ...
PMID:The effects of thionapthene-2-carboxylic acid-lysine on the hypercalcemia of malignancy in the rat. 252 8

After incubation of confluent monolayer cultures of human HT-1080 fibrosarcoma cells with purified native human plasminogen in plasminogen-depleted serum-containing medium, bound plasmin activity could be specifically eluted from the cells with tranexamic acid, an analogue of lysine. Dexamethasone reduced the amount of recoverable bound plasmin activity in a dose-dependent manner. Dexamethasone was also found to induce a time- and dose-dependent decrease in the ability of the cells to bind added plasmin. Untreated HT-1080 cells bound added plasmin with a high capacity (600,000 molecules bound per cell), and this decreased to an undetectable level after treatment with 100 nM dexamethasone. The kinetics of the loss of plasmin binding by the dexamethasone-treated sarcoma cells, a clear decrease after 4 h, correlated with those for the loss of cell-bound urokinase (u-PA) activity. Plasmin was not, however, bound to the active site of u-PA: an anti-catalytic monoclonal antibody to u-PA had no effect on plasmin binding. Other glucocorticoids, such as hydrocortisone and corticosterone, had a similar effect to dexamethasone on plasmin binding to HT-1080 cells. The effect of glucocorticoids on the plasmin receptor seemed to occur at least partly via a decrease in the affinity for plasmin, since the Kd for plasmin with untreated cells was 5.4 x 10(-9) M, and with cells treated with 5 nM dexamethasone, the Kd value for plasmin was 1.2 x 10(-7) M. These results show that glucocorticoids induce down-regulation of plasmin receptors on the surface of HT-1080 cells: a novel mechanism, in addition to the known effects of glucocorticoids on u-PA and PA inhibitors, by which human tumor cells may be disarmed of their pericellular proteolytic activity.
 ...
PMID:Down-regulation of plasmin receptors on human sarcoma cells by glucocorticoids. 253 25


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