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D R Spriggs

Publications and source records attributed to D R Spriggs.

At least 19 recordsLinked to original sources
PubMed1992

Clinical and biologic effects of combination therapy with gamma-interferon and tumor necrosis factor.

Tumor necrosis factor (TNF) and gamma-interferon (gamma-IFN) are cytokines with synergistic biologic and antiproliferative effects in vitro and in mouse models. The biologic effects of the combination of TNF and gamma-IFN, however, have not been studied well in humans. A Phase I trial was conducted of TNF and gamma-IFN therapy in 24 patients with advanced malignancies to determine the tolerability of the combination and the biologic effects of TNF and gamma-IFN in vivo. Both TNF and gamma-IFN were administered as 30-minute intravenous infusions three times per week. Doses of TNF ranged from 25 to 100 micrograms/m2; all patients received 100 micrograms/m2 of gamma-IFN. Dose-limiting toxicity consisted primarily of orthostatic hypotension and constitutional symptoms. The maximum tolerated dose level (MTDL) of 50 micrograms/m2 of TNF and 100 micrograms/m2 of IFN-gamma was less than the maximum tolerated dose (MTD) observed in previous Phase I trials of gamma-IFN and TNF alone. Biologic responses were studied in seven patients treated at the MTDL. Serum interleukin-2 receptor levels and neopterin secretion were enhanced significantly 24 hours after therapy (P = 0.002); enhancement of monocyte Fc receptor levels had borderline statistical significance (P = 0.07). With the exception of the mean fluorescent intensity on monocytes positive for histocompatibility antigen HLA-DR (P = 0.03), HLA Class I and II cell surface protein expression was not increased. The combination significantly enhanced indoleamine dioxygenase activity and serum beta 2-microglobulin expression (P less than 0.04) but not 2',5'-oligoadenylate synthetase activity, bactericidal function, or chemiluminescence. These results were compared retrospectively with those observed in previous Phase I trials of gamma-IFN and TNF alone. The combination of TNF and gamma-IFN significantly increased urinary kynurenine levels more than either TNF alone or gamma-IFN alone. Given the limitations inherent in any retrospective analysis, however, the enhancement in the other biologic parameters measured at the MTDL during this trial did not differ significantly from the changes observed at the MTD of either TNF or gamma-IFN alone. It was concluded that the combination of TNF and gamma-IFN, when administered at the MTDL of the combination, does not offer any enhancement in biologic responses over either agent alone.

2',5'-Oligoadenylate Synthetase↗
PubMed1992

A phase I trial of 5-fluorouracil, leucovorin, and dipyridamole given by concurrent 120-h continuous infusions.

A phase I trial of 5-fluorouracil (FUra) and leucovorin (LV) given with and without dipyridamole (DP) by concurrent 120-h continuous infusion was performed in 27 patients with advanced solid malignancies, 8 of whom had previously received FUra. The LV and DP doses were fixed at 500 mg/m2 daily and 7.7 mg/kg daily, respectively, whereas the FUra dose was escalated. Level 3 (450 mg/m2 FUra daily) represented the maximum tolerated dose for both FUra/LV+DP and FUra/LV. Dose-limiting stomatitis (greater than or equal to grade 3 or grade 2 occurring during the infusion) was encountered in 75% of the first courses given at level 4 (600 mg/m2 daily). Stomatitis was observed in 44/78 (56%) courses. Diarrhea was infrequent and mild. DP infusions were complicated by mild to moderate headache, which was controlled with narcotic analgesics, and mild to moderate nausea/vomiting. FUra-related toxicity was not enhanced by DP administration. Limited pharmacokinetic sampling at levels 3 and 4 revealed mean steady-state FUra concentrations of around 1.0 microM with infusions of FUra/LV+DP. Among three paired courses given with and without DP, no statistically significant difference was found in the total body clearance of FUra (P = 0.44). One partial response was seen in a patient with metastatic gastric carcinoma. For phase II trials, we recommend that concurrent 120-h continuous infusions of FUra (450 mg/m2 daily) and LV (500 mg/m2 daily) be given with and without DP (7.7 mg/kg daily) every 21 days.

Adult↗
PubMed1992

Taxol administered as a 120 hour infusion.

A Phase I trial of Taxol administered as a 120 h infusion once every 3 weeks was conducted in 20 patients with advanced cancer. The initial dose was 5 mg/m2/d (25 mg/m2 total dose) and patients received 10 mg/m2/d, 25 mg/m2/d, 30 mg/m2/d and 36 mg/m2/d. Forty-four courses of taxol were administered and all patients were evaluable for toxicity. Grade 4 leukopenia was the dose limiting toxicity observed in 50% of patients treated with 36 mg/m2/d. Significant mucositis was also observed at 30 and 36 mg/m2/d. All toxicity resolved within three weeks of treatment and no cumulative toxicity was observed. No neurotoxicity or cardiotoxicity was observed and no episodes of hypersensitivity reaction were noted. We conclude that 30 mg/m2/d is an appropriate dose for phase II testing of this schedule.

Adult↗
PubMed1992

Tumor necrosis factor, but not other hematopoietic growth factors, prolongs the survival of hairy cell leukemia cells.

In order to determine the growth factor requirements of hairy cell leukemia (HCL) cells, we studied the in vitro effects of tumor necrosis factor (TNF), interleukin (IL) 1 alpha, IL-1 beta, IL-2, IL-3, IL-4, IL-5, IL-6, B-cell growth factor (BCGF), GM-CSF, PHA-stimulated lymphocyte-conditioned media (CM), and 5637 bladder carcinoma CM on HCL cells obtained from spleens of patients with HCL. Mononuclear cells from a normal donor, obtained at post-traumatic splenectomy, served as a control. TNF prolonged the survival of HCL cells obtained from five different HCL patients when compared to cells cultured in control media alone, although cell proliferation could be demonstrated in only two of the five. HCL cells stained negative for the Epstein-Barr nuclear antigen (EBNA) both before and after 4 weeks in culture. BCGF, 5637 CM, and PHA-stimulated lymphocyte CM also prolonged the survival of HC25 and HC56 cells, although not to the same degree as TNF. Cells cultured in BCGF, however, stained positive for EBNA. None of the other recombinantly produced or purified cytokines prolonged the survival of the leukemic cells. With the exception of IL-2, none of the growth factors studied prolonged the survival of purified normal spleen (NS) cells over a 4-week period of time when compared to NS cells incubated in media alone. TNF prolonged the survival of HC25 cells in a dose-dependent manner, and a highly purified antibody to TNF abrogated the effects of TNF. HC25 cells incubated in the presence of control media alone did not constitutively produce TNF mRNA; however, incubation of the cells in the presence of TNF for 48 h induced the cells to express TNF message. We conclude that TNF is important in prolonging the survival of HCL cells, and thus may be important in the pathogenesis of this disease.

Cell Survival↗
PubMed1992

Genomic structure, induction, and production of TNF-alpha.

The TNF gene is located in close proximity to the HLA-B locus in both humans and mouse. TNF has a high degree of sequence observation across species, and this is reflected in its relatively high cross-species activity. The 5' flanking region of the TNF gene contains multiple potential regulatory sites, including consensus sequences for the AP-1 and AP-2 sites, the cAMP-responsive element, and sequences similar to the kappa B sequences found in immunoglobulin and cytokine regulatory elements. This sequence has been demonstrated to be responsive to LPS and TNF stimulation. The 3' untranslated region contains a sequence element affecting posttranslational control of TNF through mRNA stability and translation efficiency. The functional importance and interactions of these regulatory elements remain undefined. TNF is widely expressed in granulocytes, macrophages, fibroblasts, and epithelial cells. Induction of TNF can occur through a variety of stimuli, including LPS, TPA, cytokines, calcium flux, and oxygen free-radical mechanisms. A common pathway for these diverse agents remains unknown. In human monocytes, the regulation of TNF expression is regulated at both transcriptional and posttranscriptional levels. Experimental evidence suggests that phospholipase A2 and the lipoxygenase pathway may be central in the process of TNF induction in leukocytes. Down-regulation of TNF expression is better understood. The inhibition of expression appears to result from high levels of cAMP, frequently induced through the action of PGE2. TNF secretion is separately regulated and may involve the action of G binding proteins.

Amino Acid Sequence↗
PubMed1990

Phospholipase A2 activation and autoinduction of tumor necrosis factor gene expression by tumor necrosis factor.

Tumor necrosis factor (TNF) acts via a cell surface receptor to induce a variety of cellular events including cytolysis, differentiation, and mitogenesis. The mechanisms underlying the cell specific actions of TNF are not known. In the present study, postreceptor events associated with the autoinduction of TNF expression were examined in HL-60 cells. There was no detectable alteration in phospholipase C activity as measured by inositol phosphate generation or release of choline metabolites following TNF stimulation. However, TNF increased the release of arachidonic acid metabolites from HL-60 cells. This increase in arachidonic acid metabolism was associated with a 40% increase in phospholipase A2 activity. Furthermore, the release of arachidonic acid metabolites was blocked by inhibitors of phospholipase A2. Taken together, these findings indicated that TNF stimulates phospholipase A2 and arachidonic acid metabolism in HL-60 cells. The results also demonstrate that TNF expression is induced 15-30 min after stimulation with TNF and that this effect is associated with an increase in the rate of TNF transcription. This autoinduction of TNF mRNA was blocked by inhibitors of phospholipase A2. While the cyclooxygenase inhibitor indomethacin had no detectable effect, ketoconazole and nordihydroguaiaretic acid, inhibitors of lipoxygenase, also blocked the induction of TNF expression by TNF. These findings suggest that phospholipase A2 and lipoxygenase activity are required for the transcriptional activation of TNF gene expression associated with TNF stimulation of HL-60 cells.

Acetophenones↗
PubMed1990

Effects of lipopolysaccharide on phospholipase A2 activity and tumor necrosis factor expression in HL-60 cells.

LPS has been identified as a potent activator of mononuclear phagocytes. This activation is associated with TNF gene expression. The intracellular signaling mechanisms responsible for this effect, however, are unknown. The present studies demonstrate that LPS induces TNF transcripts in HL-60 promyelocytic leukemia cells. Because previous studies have demonstrated that eicosanoids are involved in the regulation of TNF gene expression in these cells, we examined the effects of LPS on activation of the arachidonic acid cascade. The results demonstrate that LPS stimulates phospholipase A2 activity and the hydrolysis of both 1,2-dipalmitoyl phosphatidylcholine and 1-steroyl 2-arachidonoyl phosphatidylcholine. In contrast, there was no detectable effect of LPS on activation of protein kinase C. We also demonstrate that inhibition of phospholipase A2 activity with bromophenacyl bromide or quinacrine blocks the induction of TNF transcripts by LPS. These findings suggested that LPS induces TNF gene expression through formation of arachidonic acid metabolites. Indeed, similar results were obtained with mellitin, a known activator of phospholipase A2 and eicosanoid production. Previous studies have also suggested that TNF mRNA levels are increased in HL-60 cells by the 5-lipoxygenase pathway and, in the present work inhibitors of this enzyme blocked LPS-induced TNF expression. Moreover, the cyclooxygenase metabolite, PGE2, as well as dibutyryl cAMP, inhibited the induction of TNF transcripts by LPS. Taken together, these results suggest that LPS induces TNF gene expression through activation of phospholipase A2 and that the level of this induction is regulated by activity of the 5-lipoxygenase and cyclooxygenase pathways.

Acetophenones↗
PubMed1990

Circulating human peripheral blood granulocytes synthesize and secrete tumor necrosis factor alpha.

Circulating peripheral blood polymorphonuclear neutrophils (PMNs) have long been considered terminally differentiated cells that do not synthesize or secrete protein. However, work of others and ourselves has shown that PMNs can secrete the cytokine interleukin 1. In the present study we investigated whether circulating PMNs are capable of synthesizing and secreting another cytokine, tumor necrosis factor alpha (TNF-alpha). Highly purified (greater than 99% granulocytes) PMNs were isolated from normal human volunteer blood and cultured with or without bacterial lipopolysaccharide (LPS) for up to 24 hr. Cell culture supernatants were collected and tested for TNF-alpha, and total RNA was isolated from cells at various times after stimulation and assessed for TNF-alpha mRNA by Northern blot techniques. The results showed that message for TNF-alpha was produced after 60 min of in vitro stimulation with LPS and was maximal at about 4 hr. TNF-alpha was secreted into the supernatant of unstimulated PMNs from two different donors during 24 hr of culture (35-50 pg/ml), but significantly more (160-190 pg/ml) was secreted by PMNs when stimulated with LPS. PMNs from six other normal volunteers showed significant LPS-stimulated secretion of TNF at 60-180 min of culture. The secreted product also had biological activity against the TNF-sensitive L-M cell line, confirming that PMNs can make and secrete immunologically and biologically active TNF. Since it is also possible for monocytes to synthesize and secrete TNF, the amount of TNF secreted by a monocyte population equal to 20% of the PMNs cultured was measured. The results showed that monocytes at a concentration 20 times that potentially contaminating the PMN populations cultured could not produce as much TNF (unstimulated, 26-65 pg/ml; stimulated, 32-87 pg/ml). The PMN must now be considered a cell capable of altering the acute inflammatory response and modulating the immune response through the synthesis and release of cytokines.

Cell Line↗
PubMed1990

A phase I study of intermittent continuous infusion high dose cytosine arabinoside for acute leukemia.

We previously administered ara-C at a dose rate of 250 mg/m2/hr for 36-72 hr to patients with leukemia. Gastrointestinal toxicity was dose-limiting. This regimen was modified to an every other day schedule, administering 24-hr periods of high dose continuous infusion ara-C, each followed by a 24-hr rest period. Sixteen patients with relapsed/refractory acute myeloid leukemia (AML) (N = 4), secondary AML (N = 2), relapsed/refractory acute lymphoblastic leukemia (N = 7), or CML in blast crisis (N = 3) received this regimen of three 24-hr infusions with two intercurrent 24-hr rest periods. Grade 3 gastrointestinal toxicity was encountered in 57% of the courses, and hypoplasia was achieved in all patients. Three of the patients died while hypoplastic, two with septicemia and another with intracranial hemorrhage. There were five responding patients (2 CRs, 3 PRs). Median steady-state plasma ara-C levels were 24 microM, 22 microM, and 20 microM during the first, second, and third 24-hr infusions, respectively. Ara-C levels ranged from 4-118 microM during the infusions and were always below 4.5 microM during the rest periods. A significant level of ara-C incorporation into DNA was detected in each of the five patients studied, thus demonstrating that (ara-C)DNA formation is detectable in blasts from patients receiving high dose continuous infusion ara-C therapy. These findings suggest that alternate day continuous infusion ara-C may be useful in the treatment of acute leukemia and CML in blast crisis.

Adult↗
PubMed1989

Circulating interleukin 6 during a continuous infusion of tumor necrosis factor and interferon gamma.

Plasma samples obtained from patients receiving a 24-h continuous infusion of human recombinant (hr)TNF or a combination of two overlapping, 24-h continuous infusions of hrIFN-gamma and hrTNF were analyzed for IL-6 in a sensitive bioassay. A transient appearance of circulating IL-6 was observed with peak levels between 3 and 6 h after the start of the hrTNF infusion. These peak levels correlated quite well with the dose of hrTNF administered (r = 0.86; p less than 0.001). The maximal value observed was 27.5 ng/ml IL-6 in a sample of a patient receiving 545 micrograms/m2 hrTNF. The combination of hrIFN-gamma (200 micrograms/m2) and hrTNF in the infusions resulted in higher IL-6 levels than a comparable dose of hrTNF alone. A maximal value of 23.5 ng/ml IL-6 was observed in a patient receiving 205 micrograms/m2 hrTNF. No IL-6 was found in the plasma of patients during the 12-h infusion with hrIFN-gamma alone, except for two borderline samples.

Drug Administration Schedule↗
PubMed1989

Increased tumor necrosis factor alpha mRNA after cellular exposure to ionizing radiation.

We report that tumor necrosis factor alpha (TNF-alpha) mRNA is increased after treatment with x-rays in certain human sarcoma cells. An increase in TNF-alpha mRNA is accompanied by the increased production of TNF-alpha protein. TNF-alpha enhances radiation lethality in both TNF-alpha-producing and -nonproducing tumor cells. These data suggest that, in addition to the direct cytotoxic effects of x-rays, production of TNF-alpha may add to radiation lethality through autocrine and paracrine mechanisms. Combinations of TNF-alpha and therapeutic radiation may be useful in clinical cancer therapy.

Cell Line↗
PubMed1989

Chronic TNF infusion causes anorexia but not accelerated nitrogen loss.

It has been proposed that many of the physiologic and metabolic changes that occur during critical illness and malignancy are mediated by the cytokine tumor necrosis factor alpha/cachectin (TNF). To test this hypothesis, a study of the metabolic responses that occurred during 5 days of continuous intravenous (I.V.) infusion of TNF both in rats and tumor-bearing humans was conducted. TNF administration was associated with anorexia, fluid retention, acute phase responses, and negative nitrogen balance. In both species, changes in nitrogen balance were related to the onset of anorexia and not to the development of hypermetabolism and accelerated net tissue breakdown. TNF may represent the primary afferent stimulus inducing many of the metabolic changes that occur during critical illness, but it is not solely responsible for the accelerated net proteolysis that occurs in these patients.

Acute Disease↗
PubMed1989

A phase I trial of recombinant human tumor necrosis factor and interferon-gamma: effects of combination cytokine administration in vivo.

The combination of tumor necrosis factor (TNF) and interferon-gamma has synergistic bioactivity in numerous preclinical model systems. We have tested this potential synergism in vivo by administration of both cytokines to patients with advanced cancer using overlapping 24-hour continuous intravenous (IV) infusions in a phase I trial. Thirty-six patients were treated with a fixed dose of interferon-gamma (200 micrograms/m2/d) with interpatient dose escalation of TNF (from 5 to 205 micrograms/m2/d). The dose-limiting toxicity at the maximal-tolerated dose (MTD) of TNF (205 micrograms/m2) with interferon-gamma was hypotension. Other toxicities noted included an influenza-like syndrome, transient decreases in circulating leukocyte and platelet counts, subclinical evidence of disseminated intravascular coagulation, and the sporadic occurrence of acute pulmonary toxicity. The recommended phase II dose for this combination schedule is TNF, 136 micrograms/m2, with interferon-gamma, 200 micrograms/m2. The addition of interferon-gamma to TNF resulted in a greater than three-fold increase in toxicity compared with TNF administered as a single agent, supporting the hypothesis that the combination of these cytokines may induce synergistic effects in vivo.

Adult↗
PubMed1989

Effects of tiazofurin on globin and proto-oncogene expression in K562 erythroleukemia cells.

Tiazofurin (2-beta-D-ribofuranosylthiazole-4-carboxamide, NSC 286193) is a synthetic nucleoside inhibitor of inosine monophosphate dehydrogenase. This agent has recently been shown to induce differentiation of human leukemia cell lines. In the present study, we have monitored the effects of tiazofurin on differentiation and proto-oncogene expression in K562 erythroleukemia cells. Tiazofurin induced K562 cell hemoglobin production in a concentration-dependent manner. This induction of a differentiated phenotype was also associated with a loss of proliferative capacity. In contrast to the reversible effects of hemin on induction of K562 cell hemoglobin synthesis, the effects of tiazofurin were irreversible. Northern blot analysis of K562 cells treated with 10 microM tiazofurin demonstrated the accumulation of alpha- and gamma-globin mRNA. The results also demonstrate that there was little if any effect of tiazofurin on levels of c-myc, c-myb, or c-abl mRNA. Furthermore, there were no detectable changes in Ki-ras, Ha-ras or N-ras expression at the mRNA and protein levels in tiazofurin-treated K562 cells. These findings suggest that tiazofurin induces changes in levels of globin transcripts but has little if any effect on c-myc, c-myb, c-abl, or c-ras gene expression in K562 cells.

Actins↗
PubMed1989

Tumor necrosis factor infusions have a procoagulant effect on the hemostatic mechanism of humans.

Several investigators have reported that tumor necrosis factor (TNF) can alter the hemostatic properties of vascular endothelial cells in vitro. We have examined the in vivo effects on the hemostatic mechanism of recombinant human TNF administered as a continuous intravenous infusion to 23 cancer patients with active disease. A battery of sensitive and specific immunochemical techniques were used to monitor changes in blood coagulability. Serial determinations of F1 + 2, the protein C activation peptide (PCP), and fibrinopeptide A (FPA) were obtained prior to the initiation of the TNF infusions and at three and 24 hours after the start of therapy in 12 individuals who received greater than 3 x 10(5) U/m2/24h. The mean levels of F1 + 2, PCP, and FPA were significantly elevated at both time points as compared to the baseline values. The metabolic behavior of 125I-F1 + 2 in an animal model was not affected by infusions of the cytokine. We therefore conclude that the observed elevations in the concentration of this marker in humans receiving TNF result from hemostatic system hyperactivity. In 11 subjects infused with 1 x 10(5) to 2.4 x 10(5) U/m2/24 h of the cytokine, the mean levels of F1 + 2, PCP, and FPA were not significantly greater at 24 hours as compared with the baseline values, indicating that there is a threshold dose at which the cytokine can exert a biochemical effect on the coagulation system. Our studies demonstrate that TNF is able to provide a substantial net procoagulant stimulus to the hemostatic mechanism, and suggest that this cytokine may be a mediator of certain hypercoagulable states in humans.

Blood Coagulation Tests↗
PubMed1988

Effects of tiazofurin on protooncogene expression during HL-60 cell differentiation.

The synthetic nucleoside analogue, tiazofurin (2-beta-D-ribofuranosylthiazole-4-carboxamide, NSC 286193) is an inhibitor of the enzyme inosine monophosphate (IMP) dehydrogenase and depletes guanine nucleotide pools. In the present study, we have monitored the effects of tiazofurin on human HL-60 promyelocytic cell differentiation and protooncogene expression. Tiazofurin (10 microM) induced a more differentiated HL-60 cell phenotype as determined by histochemical staining and decreased myeloperoxidase gene expression. This induction of differentiation was associated with a loss of proliferative capacity and decreases in clonogenic survival. The results also demonstrate that tiazofurin induces a down-regulation of c-myc mRNA levels. In contrast, there was no detectable change in the level of 3.8-kilobase c-myb transcripts. Furthermore, treatment of HL-60 cells with tiazofurin resulted in the appearance of an additional c-myb mRNA with an apparent size of 3.3 kilobases. The addition of guanosine to tiazofurin-treated HL-60 cells prevented the down-regulation of c-myc transcripts and also inhibited induction of the 3.3-kilobase c-myb transcript. Moreover, this additional transcript was not detected during induction of HL-60 cells by dimethyl sulfoxide, tumor necrosis factor, and retinal, but was induced by another IMP dehydrogenase inhibitor, mycophenolic acid. These results suggest a role for guanosine ribonucleotides in the regulation of c-myc and c-myb gene expression during HL-60 cell differentiation. The results also suggest that changes in c-myb expression can be dissociated from that of c-myc and induction of myeloid differentiation.

Cell Differentiation↗
PubMed1988

Recombinant human tumor necrosis factor administered as a 24-hour intravenous infusion. A phase I and pharmacologic study.

Recombinant human tumor necrosis factor (rH-TNF) is a cytokine with direct antitumor properties. In a phase I trial we continuously infused rH-TNF for 24 hours. We gave a total of 115 courses of therapy to 50 patients. Doses ranged from 4.5 to 645 micrograms of rH-TNF/m2. Systemic toxicity, including fever, chills, fatigue, and hypotension, increased with the dose of rH-TNF administered. Doses greater than 454 micrograms/m2 frequently caused severe lethargy and fatigue, which precluded hospital discharge of the patient at the completion of therapy. The dose-limiting toxicity was hypotension, and five patients treated at the two highest dose levels required dopamine treatment. Other organ-specific toxicity was modest and spontaneously resolved after 48 hours. The 24-hour infusions of rH-TNF were associated with significant decreases in serum cholesterol and high-density lipoprotein levels. Pharmacokinetic studies using an enzyme-linked immunosorbent assay demonstrated peak plasma rH-TNF levels of 90-900 pg/mL. Despite continuous infusion of rH-TNF, no steady-state level was achieved. The recommended phase II dose for rH-TNF as a 24-hour continuous infusion is 545 micrograms/m2.

Adolescent↗