Subcellular localization and targeting of glucocorticoid receptor protein fusions expressed in transgenic Arabidopsis thaliana

An animal system of inducible activation of protein fusions with the binding domain of glucocorticoid receptor (BDGR) was tested in Arabidopsis thaliana by monitoring dexamethasone (DEX)-induced nuclear targeting of reporter constructs. Two constructs containing green fluorescent protein (GFP), human homeobox protein Hanf-1 and Xenopus laevis BDGR were used, GFP/Hanf-1/BDGR and GFP/BDGR. The control construct contained GFP alone. In the absence of DEX both fusion proteins were uniformly distributed in the cytoplasm of root cells, but showed strong association with plastids in plant aerial parts. DEX treatment of roots prompted a strong and reversible nuclear accumulation of GFP/Hanf-1/BDGR, but not GFP/BDGR. Thus, in roots, the specific nuclear translocation of GFP/Hanf-1/BDGR was driven by Hanf-1 and tightly regulated by BDGR. However, in plant aerial parts treated with DEX, nuclear translocation of GFP/Hanf-1/BDGR was observed only in a few cases, and most part of the fusion protein was incorrectly and irreversibly targeted to plastids. Protease X digestion of isolated chloroplasts showed that BDGR fusion proteins were translocated into the chloroplast envelope and bound to envelope membranes, probably due to association with the chloroplast import apparatus. Thus, for efficient use of the glucocorticoid-inducible system in plants, it will be necessary to modify BDGR structure to prevent incorrect targeting of fusion proteins.

Molecular cloning and expression patterns of three putative functional aldehyde oxidase genes and isolation of two aldehyde oxidase pseudogenes in tomato

The final steps in the biosynthesis of the plant hormones abscisic acid (ABA) and indole-3-acetic acid (IAA) have been shown to be catalyzed by aldehyde oxidases (AO). We have cloned three putative functional AO genes (TAO1, TAO2 and TAO3) and two putative AO pseudogenes (TAO4 and TAO5) in tomato. The TAO1 cDNA described here includes the correct amino terminus of the encoded TAO1 protein and is different at the 5'-end from the TAO1 sequence in GenBank (accession number U82558). Northern analysis shows that TAO1 is expressed mainly in vegetative tissues and TAO2 is expressed in both vegetative and reproductive tissues. TAO3 expression was not detectable by Northern hybridization. These results suggest that each AO may play different roles in the regulation of tomato growth and development.

[Intensification of chemotherapy dosage in metastatic breast carcinoma?]

During the last decades, improvements in the median survival time in patients with metastasized carcinoma of the mamma were hardly achieved. There ist still a lack of evidence that the increase in the rate of remissions due to conventional chemotherapy leads to an improvement in survival time. In 450 female patients with metastasized carcinoma of the mamma, the survival time was analyzed with the begin of the metastatic spread in relation to the treatment success of the first palliative chemotherapy. The survival time of the responder group was not significantly different to the group with a stationary tumor (p = 0.5). As patients with primary hormone therapy were included, this result changed if patients only with prognostically unfavorable characteristics (high-risk group) were selected, which received primarily and exclusively a cytostatic chemotherapy. The responder only (partial and complete responder) are profitting from the chemotherapy with a significant increase in survival time in comparison to the group with a stationary tumor (p = 0.02 and p = 0.006). Therefore, a stationary tumor in the high risk group is a result as bad as tumor progression.

Effect of chlormethiazole on hepatic monooxygenases activity in vivo

Chlormethiazole is a strong inhibitor of cytochrome P-450-dependent monooxygenases in isolated human liver microsomes. To assess its effect in vivo, we measured the pharmacokinetic parameters of antipyrine (1.2 g orally) and tolbutamide (0.5 g i.v.) before and after administration of chlormethiazole 314 mg b.d. for 2 days to 8 healthy volunteers. The elimination of neither substance was affected, indicating that chlormethiazole did not inhibit in vivo the cytochrome P-450 isozymes responsible for the elimination of antipyrine and tolbutamide.

[Therapeutic results and toxic side effects of the cytostasan, adriamycin and vincristine combination as second line therapy in metastatic breast cancer]

Remission rates of 30-50% can be obtained using different cytostatic combinations in second line therapy of metastatic breast cancer. The combination of adriamycin and vincristin with cytostasan revealed a remission rate of 50% in 62 CMF-pretreated patients. Considerable toxic side effects led to a dose reduction of cytostasan and adriamycine in 43 patients without clinical efficacy loss. The long remission periods of the total responders (8-23 months) were remarkable. Both, 3 patients with bone +/- soft tissue metastasis and 4 patients with visceral metastasis benefited from a clinical total remission. The remission rates indicated no significant differences between the group of patients with soft tissue +/- bone metastasis (47.3%) and that with a predominantly visceral metastasis (50%). The CyAV-combination with a low dosage provides an effective therapeutical scheme with acceptable side effects for CMF-pretreated patients with breast cancer.

[Results of hormone therapy with aminoglutethimide (Rodazol) in postmenopausal metastatic breast cancer]

44 postmenopausal women with progressive soft tissue, osseous and/or pleuropulmonal metastases of breast cancer were treated with aminoglutethimide (Rodazol) and hydrocortisone. 40 of the 41 patients, evaluated for treatment results, were pretreated hormonally and 17 were additionally pretreated chemotherapeutically. Objective remissions were achieved in 8 of the total of 41 patients (20%) and in 7 of the women (35%), who had previously responded to tamoxifen. Pain reduction was achieved in 4 of 17 cases (23%) with skeletal pain as the main symptom. The response rate was lower than expected. Primary hormonal therapy with Rodazol cannot be recommended in the osseous type of metastatic spread.

Pharmacokinetics of adriamycin, adriamycinol, and antipyrine in patients with moderate tumor involvement of the liver

The pharmacokinetics of adriamycin, its metabolite adriamycinol, and antipyrine were studied in 17 patients with moderate tumor involvement of the liver and compared to that of 19 tumor patients with normal liver function (Preiss et al. 1985). The individual liver function parameters deviated from normal by a factor ranging from 2.5 to 12.2. The t1/2 alpha and t1/2 beta, the AUC (corrected for body weight and dose) and the total body clearance (CL, corrected for body weight) of adriamycin did not differ significantly between the two groups of patients. Likewise, there was no difference in the kinetic parameters of antipyrine between the two groups. Unlike adriamycin and antipyrine, adriamycinol was found to have a significantly longer t1/2term (60.5 vs 28.3 h, P less than 0.001), an increased AUC (3.00 vs 1.43 h/ug per ml, P less than 0.02), and a higher AUCadriamycinol/AUCadriamycin ratio (0.94 vs 0.52, P less than 0.02) in patients with moderate tumor involvement of the liver. The CL, the AUC, and t1/2 beta of adriamycin correlated significantly (P less than 0.001 and P less than 0.01) with the corresponding kinetic parameters of antipyrine, but not with the usual liver function parameters. No correlation could be found between the kinetic parameters of adriamycinol and those of antipyrine.

[The pharmacokinetics of bendamustine (Cytostasane) in humans]

The pharmacokinetics of bendamustine (Cytostasane) was determined in plasma on seven patients after its intravenously and oral application, respectively. Cytostasane was given in a dosis of 4.2-5.5 mg . kg-1 as an intravenous infusion over 3 min and as gelatine capsules in a 7-d intervall. Its elimination from the plasma is fast, monoexponentially and two-phasic after intravenous application (t1/2 alpha = 9.6 min, t1/2 beta = 36.1 min). The AUC was 11.17 micrograms . ml-1 . h, the central distribution volume 11.15 l and the distribution volume in steady state 20.51 l. The mean total clearance was 528.9 ml . min-1. After oral application maximal plasma levels of Cytostasane were detectable before 1 h. The mean oral bioavailability was 0.57, ranged from 0.25 to 0.94. Cytostasane undergoes metabolism. Its hydrolysis in plasma is slow (t1/2 = 1.67 h). After Cytostasane the depression of leucocytes was mild.

Plasma pharmacokinetics of adriamycin and antipyrine and its relation to the therapeutic and toxic effects

After a simultaneous administration of adriamycin and antipyrine to 19 tumor patients, the plasma kinetics of both drugs, the therapeutic effect and the reaction to white blood cells were determined. Antipyrine was given orally at a dose of 875 mg, whereas adriamycin was administered by means of intravenous infusion for 20 min at 60 mg/m2. This application was repeated in eight patients after three weeks. Nine patients had a normal liver function. In ten patients, slight increases were found in individual liver function parameters. All patients were free from metastases of the liver and had bilirubin levels within the normal range. Antipyrine followed an open one-compartment model, whereas adriamycin followed an open two-compartment model. In the mean, t1/2 el and Cl tot of antipyrine were found to be 16.1 h and 32.9 ml/min, t1/2 beta and Cl tot of adriamycin were 23.1 h and 877 ml/min. For antipyrine and adriamycin, these parameters varied interindividually by the factors 2.8 and 3.1, respectively. No correlations were found between the liver function parameters, and the kinetic elimination parameters and the areas under the curves of both drugs. However, significant positive correlations were found to exist between t1/2 el antipyrine and t1/2 beta adriamycin and between the areas under the curves of the two drugs. A relationship between the AUC adriamycinol/AUC adriamycin ratio (which was 0.52 in the mean) and the antipyrine elimination rate did not exist. As compared to 12 persons with no response or progression, the seven patients with partial or complete response had a significantly higher AUC and a significantly lower Cl tot of adriamycin. As compared to the patients with elimination half-life values of less than 20 h, five patients with antipyrine elimination half-life values of more than 20 h had a significantly longer adriamycin elimination beta-phase and a stronger depressive effect on the white blood cells. The results obtained suggest that the antipyrine kinetics in patients with normal or slightly impaired liver function is a useful parameter for an assessment of the depression of white blood cells and the dose adjustment for adriamycin.

[Bioavailability of cyclophosphamide following oral administration in high doses]

Mean rate of absorption of cyclophosphamide after oral administration from studies in which the drug is given in doses of 0,7 g/m2 body surface both orally and intravenously to the same 18 tumor patients is 87.7% (s - 21.1%). The drug may be administered orally with good bioavailability at the high dose.