Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0006826 (cancer)
 1,092,456 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

This study was conducted to further characterize the previously described phenomenon of growth inhibition of neoplastically transformed C3H/10T1/2 cells (T10T1/2) by nontransformed C3H/10T1/2 clone 8 mouse embryo fibroblast (10T1/2) cells in the presence of inhibitors of cyclic adenosine 3':5'-monophosphate (cAMP) phosphodiesterase. The cAMP phosphodiesterase inhibitor dl-4-(3-butoxy-4-methoxybenzyl)-2-imidazolidinone (RO20-1724) was shown to be completely nontoxic to T10T1/2 cells at 10(-4) M, yet when added to mixed cultures of T10T1/2 cells and postconfluence growth-arrested 10T1/2 cells, colony formation and [3H]thymidine incorporation into T10T1/2 cells were virtually eliminated. This effect was dose dependent and was reversible upon drug withdrawal. In 10T1/2 cells, RO20-1724 caused a dose-dependent increase in cAMP levels from about 5 to 150 pmol/10(6) cells; in T10T1/2 cells, 10(-4) M drug treatment caused a 5-fold elevation in cAMP without a clear dose dependency. Cyclic guanosine 3':5'-monophosphate levels in 10T1/2 cells fell by 50% with drug treatment but were unmeasurable in T10T1/2 cells. When intracellular cyclic AMP levels were elevated by the adenyl cyclase stimulator forskolin, growth inhibition of T10T1/2 cells was again induced in mixed cultures but was not observed when added to T10T1/2 cells alone. Addition of RO20-1724 to low concentrations of forskolin produced a greater than additive effect on growth inhibition. Growth inhibition of T10T1/2 cells by RO20-1724 was shown to (a) require contact with, or extremely close proximity to, a confluent monolayer of 10T1/2 cells, (b) be maximum when seeded upon a growth-inhibited monolayer and not an actively growing 10T1/2 culture, and (c) not be decreased by continuous agitation of the culture medium, indicating that readily diffusible inhibitory factors are not involved. A model is presented whereby transformed cells can respond to but cannot themselves generate growth-inhibitory signals produced by post-confluence growth-inhibited nontransformed cells. The existence of these cellular interactions may well explain problems in the quantitation of transformed foci encountered in the use of this cell line as an assay system for chemical and physical carcinogens.
Cancer Res 1985 May
PMID:Requirements for and kinetics of growth arrest of neoplastic cells by confluent 10T1/2 fibroblasts induced by a specific inhibitor of cyclic adenosine 3':5'-phosphodiesterase. 298 40

The s-triazine derivatives have shown preclinical antitumor activity against several histologic types. The most widely used compound of this class in the clinic, hexamethylmelamine, has been largely restricted to oral use because of its low solubility and lack of stability in solutions suitable for parenteral administration. New analogs were sought which were soluble and stable and retained antitumor activity. Pentamethylmelamine (PMM), the monodemethylated derivative, showed these promising characteristics. Preclinical toxicology studies of PMM in mice, dogs, and monkeys showed toxic manifestations that involved the hematopoietic, lymphatic, renal, male reproductive, gastrointestinal, and nervous systems; these changes were both infusion-rate- and dose-dependent. Clinical phase I trials of PMM were performed using a variety of infusion durations and frequency schedules. The dose-limiting toxic effect common to all of these trials was protracted nausea and vomiting. In addition, some studies reported dose-limiting central nervous system manifestations in the form of agitation, drowsiness, somnolence, and even coma. Mild to moderate hematologic changes were noted. Because of the severity and frequency of the gastrointestinal and central nervous system toxic effects observed in the completed trials, no new clinical trials of PMM sponsored by the National Cancer Institute are planned. However, the interest in finding a clinically useful parenteral triazine continues.
Cancer Treat Rep 1986 Mar
PMID:Pentamethylmelamine: review of an aqueous analog of hexamethylmelamine. 308 12

This study documents the ability of substrata material derived from well but not poorly differentiated colon carcinoma cells to alter the biological characteristics of a separate colon carcinoma cell line (MOSERSF). To assess changes induced by the presence of these substrata, MOSERSF cells were screened for (a) morphological features, (b) secretion of carcinoembryonic antigen (CEA), (c) alteration of urokinase levels, and (d) sensitivity to the growth-inhibitory peptide transforming growth factor beta. Morphologically, MOSERSF cells grown on plastic displayed a rounded shape and could be detached by agitation. Subculturing of these cells onto substrata laid down by well differentiated (mature) colon carcinoma cells resulted in cell attachment and spreading. These changes did not manifest themselves when cells were plated on material derived from poorly differentiated (primitive) colon cells. Conditioned medium from MOSERSF cells grown on plastic or on colon-derived material from the well and poorly differentiated colon cells were compared for CEA levels. Substrata derived from undifferentiated cells were without effect on assayable CEA (substrata absent, 1.4 ng/ml/10(6) cells/72 h; substrata present, 1.4-1.7 ng/ml/10(6) cells/72 h). However, growth of MOSERSF cells on material deposited by well differentiated colon cells resulted in a 3-fold increase in the level of CEA. Spent medium was also analyzed for urokinase. A high level of the protease (20.3 ng/ml/10(6) cells/72 h) was expressed by MOSERSF cells. The concentration of the enzyme was reduced by over 50% when MOSERSF cells were propagated on substrata laid down by well differentiated cells. An enhanced sensitivity to the growth-retarding effects of transforming growth factor beta was seen with certain substrata. On plastic, transforming growth factor beta inhibited proliferation of MOSERSF cells with a median effective concentration of 0.65 ng/ml. However, on substrata from mature but not primitive cells, MOSERSF cells exhibited an increased sensitivity to the peptide (median effective concentration, 0.16 ng/ml). Colon-derived material obtained from both well differentiated and poorly differentiated colon carcinoma cells was compared after [35S]-methionine metabolic labeling. More [35S]methionine was incorporated into the material from the "mature" colon cells. The substrata could also be distinguished by quantitative differences in a number of high molecular weight proteins. Immunofluorescence of colon-deposited material revealed the presence of laminin and fibronectin.
Cancer Res 1988 May 15
PMID:Alterations of the biological characteristics of a colon carcinoma cell line by colon-derived substrata material. 316 26

A phase I study of single i.v. doses of a new sugar containing nitrosourea 6-deoxy-3,5 di-O-methyl 6-(3 methyl-3-nitrosoureido)-alpha-D-glucofuranoside (CGP 6809, EDMN) has been carried out in 47 patients with advanced solid tumors. Nine dose levels between 200 and 4500 mg/m2 were examined. Nausea and vomiting were seen in most patients but were controlled with antiemetics. Myelosuppression was minimal. The dose-limiting toxicity was hepatotoxicity, occurring early (peak at days 2-4) and resolving rapidly. No cumulative toxicity was seen with an every 6 weeks schedule. Other toxicities were abdominal pain, diarrhea, arm pain, restlessness, and headache. Pharmacokinetic studies in 20 patients using an HPLC assay and in 5 patients using [14C]EDMN showed a short half-life, rapid plasma clearance, rapid metabolism, and minimal excretion of unchanged drug. There was one partial response in a patient with colon carcinoma. The recommended dose for phase II studies in 3750 mg/m2 every 6 weeks.
Cancer Chemother Pharmacol 1987
PMID:Phase I clinical trial of ethyl 6-deoxy-3,5-di-O-methyl 6-(3 methyl-3-nitrosoureido)-alpha-D-glucofuranoside (CGP 6809). 330 87

Combinations of metoclopramide and dexamethasone given intravenously control vomiting caused by high doses of cisplatin. Lorazepam and diphenhydramine are useful adjuncts to antiemetics. In a double-blind trial, 120 patients receiving high-dose cisplatin (120 mg/m2) for the first time were randomly assigned to receive either lorazepam (1.5 mg/m2) or diphenhydramine (50 mg) intravenously, 45 minutes prior to cisplatin. In addition, all patients received intravenous dexamethasone (20 mg) 40 minutes prior to chemotherapy along with metoclopramide (3 mg/kg) 30 minutes before and 90 minutes after cisplatin. Patients were directly observed in the hospital after cisplatin administration and completed a subjective assessment questionnaire. Overall, 60% of patients experienced no vomiting, and 83% had two or fewer emetic episodes during the study. There were no significant differences in objective antiemetic control between the two regimens. Only 3% of patients receiving lorazepam experienced treatment-related restlessness as opposed to 19% given diphenhydramine (P = 0.007). Less recall of chemotherapy administration (P less than 0.001), more sedation (P = 0.003), and transient enuresis while sedated (P = 0.0002) were characteristic of patients receiving lorazepam. Patient-generated ratings revealed less anxiety (P = 0.0001) for those individuals given the lorazepam-containing combination. Both regimens were well accepted, with 89% of patients receiving the lorazepam combination and 83% of those given the diphenhydramine regimen wishing to receive the same drugs in the future. Some degree of delayed vomiting occurred in 85% of patients during the 4-day period following this study. During the time that patients are at the greatest risk for emesis, the 24 hours immediately following cisplatin, three drug antiemetic combinations of either lorazepam or diphenhydramine with metoclopramide plus dexamethasone stopped cisplatin-induced emesis for the majority of patients and lessen other treatment-related side effects. Less restlessness and anxiety were observed among individuals receiving the lorazepam-containing combination.
Cancer 1987 Dec 01
PMID:Antiemetic control and prevention of side effects of anti-cancer therapy with lorazepam or diphenhydramine when used in combination with metoclopramide plus dexamethasone. A double-blind, randomized trial. 331 76

A case of agitated delirium secondary to bilateral occipital cerebral infarctions in a cancer patient was refractory to trials of large doses of intravenous psychotropic agents, but continuous intravenous infusion of haloperidol controlled agitation rapidly and safely. A total haloperidol dose of 600 mg/day was used without complications. Haloperidol by continuous infusion should be considered in the management of severe, refractory agitation in patients who are medically ill.
 ...
PMID:Treatment of severe, refractory agitation with a haloperidol drip. 337 30

This study investigated the antiemetic properties of four different doses of prochlorperazine (10 mg, 20 mg, 30 mg, 40 mg) when given randomly to patients receiving four cycles of the same dose of cisplatin-based chemotherapy. Prochlorperazine was given to 71 patients by slow intravenous infusion 30 minutes before and 3 and 6 hours after the start of cisplatin chemotherapy. The higher doses of prochlorperazine proved to be effective in the control of cisplatin-induced emesis. For the 20 patients who completed all 4 study cycles of treatment, a relationship was discerned between the dose of prochlorperazine administered and the antiemetic effect. When all 71 patients were analyzed in terms of the results of the first cycle of chemotherapy, a significant dose-response effect was also found. Overall toxic reactions in 82 treatment cycles using either 30 mg or 40 mg of prochlorperazine were dystonia (1 patient), restlessness (2), hypotension (3), and drowsiness (12). This study demonstrates that higher-than-conventional doses of prochlorperazine have an impressive antinauseant effect with only moderate toxicity.
Cancer 1987 Nov 01
PMID:High doses of prochlorperazine for cisplatin-induced emesis. A prospective, random, dose-response study. 344 Feb 26

Fifteen cancer patients receiving cisplatin-containing chemotherapy participated in two antiemetic studies. In Study 1 they received standard antiemetics in low doses on demand, and in Study 2 the same patients participated in an open randomized cross-over study between metoclopramide 1 and 2 mg/kg i.v. X 5. Serum metoclopramide was determined by HPLC. Self-reporting of nausea using a visual analogue scale (VAS) was compared with observer rated scores. Tolerability and volume vomited were assessed by nurse observers. The biological half-life of metoclopramide was 9.9 h, the volume of distribution was 9.9 l/kg and the clearance was 0.68 l/h/kg. The pharmacokinetics of high dose metoclopramide was linear in the range 0.15-2 mg/kg X 5, with very little accumulation. Compared to standard antiemetics, both high dose regimens of metoclopramide had a significant effect on nausea, but no effect on the volume vomited. Self reports of nausea were significantly correlated with observer rated values. Tolerance of high dose metoclopramide was good except in 3 patients who left the study because of restlessness and trismus. It is concluded that high dose metoclopramide probably can be administered for several consecutive days without appreciable accumulation of the drug. Self-reporting of nausea by patients on VAS is a simple and feasible method of evaluation. The finding that metoclopramide affects nausea but not vomiting supports the hypothesis that nausea and vomiting should be evaluated separately in assessing antiemetic efficacy.
 ...
PMID:Antiemetic effect and pharmacokinetics of high dose metoclopramide in cancer patients treated with cisplatin-containing chemotherapy regimens. 378 Aug 24

Hexamethylene bisacetamide (HMBA, NSC 95580) has been demonstrated to be the most effective of the known and studied polar-planar compounds at inducing differentiation in a wide variety of leukemic and nonleukemic cell lines. Although HMBA demonstrated no antineoplastic activity in preclinical testing, it was selected for clinical development on the basis of its potent differentiating capabilities in vitro. In this phase I study, HMBA was administered as a continuous five-day infusion every 3 weeks to patients with advanced cancer. Twenty-three patients received 35 evaluable courses at doses that ranged from 4.8 to 33.6 g/m2/d. Dose-limiting toxicities included renal insufficiency, a hyperchloremic metabolic acidemia/acidosis, and CNS toxicities manifested by agitation and delirium, which progressed to coma in one patient who developed concomitant renal insufficiency. Moderate myelosuppression, mucositis, nausea, and vomiting were also observed. The pharmacokinetics of HMBA best fit a single compartmental model and disposition is primarily by renal elimination. Renal excretion of HMBA and of the primary metabolite, 6-acetoamidohexanoic acid, together account for the disposition of 66% to 93% (mean, 74%) of the infused drug. Based on this trial, the maximum tolerated and recommended phase II doses for HMBA administered on this schedule are 33.6 and 24 g/m2/d, respectively. However, since steady-state HMBA levels at these doses were in the range of 1 to 2 mmol/L, only approaching the lower limit demonstrated for in vitro differentiating effectiveness, and because of evidence suggesting that the exposure period is an important variable in the induction of differentiation, additional studies examining longer periods of infusion are warranted.
 ...
PMID:Phase I and pharmacologic study of hexamethylene bisacetamide in patients with advanced cancer. 378 6

Hexamethylene bisacetamide (HMBA), a potent differentiating agent, was tested in patients with refractory, solid tumors. Twenty patients received 25 evaluable courses. HMBA was given by continuous i.v. infusion for 5 consecutive days with courses repeated every 4 wk, provided there was acceptable, reversible toxicity. The starting dose was 4.8 g/m2/day for 5 days with escalations in subsequent cohorts of patients to 43.2 g/m2/day for 5 days. The patients included 12 females and eight males with median age of 56 yr (range 35 to 75 yr) and a median performance status of 80% (range, 60 to 100%). All except two patients had received prior chemotherapy, radiation therapy, or both. Metabolic acidosis and neurotoxicity, consisting of agitation, hallucinations, confusion, and alteration of consciousness, were dose dependent and dose limiting. The one patient treated with 43.2 m/m2/day became acidotic, agitated, and disoriented but recovered to his previous mental and electrolyte status by 8 days after the end of the HMBA infusion. One patient treated with 33.6 g/m2/day became severely acidotic (pH 7.07) and obtunded and also developed myocardial and cerebral infarctions during the HMBA infusion. The other two patients treated with 33.6 g/m2/day became mildly agitated during drug infusion. Six patients were treated at 24 g/m2/day without neurotoxicity. Transient renal insufficiency was seen in the two patients with severe neurotoxicity and in three other patients. Dose-related, mild to moderate nausea and vomiting were observed in ten patients. Four patients developed cutaneous herpes infections during treatment. White blood cell depression was not dose related, and at 24 g/m2/day, the median white blood cell nadir was 4,500/microliter (range, 2,000 to 7,900/microliter). Thrombocytopenia was dose related. At 24 g/m2/day, the median platelet count nadir was 207,000/microliter (range, 66,000 to 542,000/microliter). No objective tumor regressions were noted. HMBA pharmacokinetics was studied at all dosages. Plasma and urine samples from 20 patients were analyzed by gas-liquid chromatography for parent compound. HMBA plasma steady-state concentrations (Css) were achieved in all patients by 12 to 24 h into infusion. Once Css was achieved, daily variation was generally less than or equal to 10% from the mean Css. HMBA plasma Css increased linearly with dose, but there was variation in the Css achieved in individual patients at each dose. Doses of 24 to 33.6 g/m2/day consistently produced plasma HMBA Css of 1 to 2 mM matching concentrations required for differentiation in vitro.(ABSTRACT TRUNCATED AT 400 WORDS)
Cancer Res 1987 Jan 15
PMID:Phase I clinical and pharmacokinetic study of hexamethylene bisacetamide (NSC 95580) administered as a five-day continuous infusion. 379 Dec 46


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