Increased delivery of erucylphosphocholine to C6 gliomas by chemical opening of the blood-brain barrier using intracarotid pentylglycerol in rats

BACKGROUND: Erucylphosphocholine (ErPC) has been shown to exert strong antineoplastic effects against various brain tumor cell lines in vitro. Since ErPC only enters the brain after long-term treatment, ineffective drug delivery to the tumor is considered to be the reason for the moderate responses to chemotherapy with ErPC observed in animal brain tumor models. We investigated a recently described method for chemically opening the blood-brain barrier (BBB) using intraarterial administration of alkylglycerols to increase the transfer of ErPC into the brain. METHODS: ErPC (40 mg/kg) was given to C6 glioma-bearing rats either as a single intracarotid bolus injection in the presence or absence of 1- O-pentylglycerol (300 m M) or as an intracarotid infusion in conjunction with bradykinin. Brain tissue concentrations were analyzed and compared to values obtained after intravenous ErPC treatment over 14 and 30 days (cumulative ErPC doses of 210 and 350 mg/kg, respectively). RESULTS: Pentylglycerol-induced BBB opening resulted in a significant increase in ErPC delivery to the tumor (17-fold) and, to a lesser extent, to the surrounding ipsilateral brain (7-fold) compared to intraarterial ErPC administration without alkylglycerol ( P<0.05). Furthermore, the resulting ErPC concentrations in the brain tumor exceeded those obtained in tumor and tumor-free brain after long-term intravenous ErPC administration. In contrast to this, intracarotid bradykinin did not increase the transfer of ErPC to the tumor or tumor-free brain. CONCLUSIONS: The intracarotid administration of pentylglycerol represents a novel and nontoxic method of overcoming the limited access of ErPC to both brain tumors and brain tissue adjacent to tumors. The present results provide further evidence that chemical opening of the BBB by intraarterial alkylglycerols is a promising new concept for improving delivery of chemotherapeutic agents to brain tumors.     

Effect of gemcitabine on acute and late radiation toxicity of skin and underlying soft tissues to single-dose irradiation in a nude mice model

PURPOSE: To investigate the influence of gemcitabine (GEM) on acute and late toxicity of radiotherapy (XRT) in an in vivo model of acute skin reactions and late fibrotic sequelae of skin and underlying soft tissues. METHODS AND MATERIALS: Single-fraction XRT was applied to the right hind leg of nude mice under ambient conditions. Single-dose GEM was applied i.p. (550 mg/kg body weight). In a first set of experiments, the influence of timing of chemotherapy relative to the onset of irradiation was investigated with GEM application 36, 24, and 2 h before and 24 h subsequent to 40 Gy XRT. With a fixed interval between chemotherapy and XRT taken from these studies, the dose-response relationship was examined for XRT in the range of 20-65 Gy. Control mice were irradiated without GEM treatment. Using a scoring system, onset, duration, and extent of acute skin reactions were analyzed. Skin fibrosis was measured by intracutaneous ink-mark separation. Soft tissue fibrosis was assessed using the leg contracture assay. ED50 calculations were performed for extent of acute and late reactions. RESULTS: Timing of GEM application relative to XRT had no significant influence on acute skin reactions or on fibrotic changes. Onset, duration, and extent of acute skin toxicity, as well as skin and leg contracture, were not significantly modulated by GEM in the dose-response experiments with GEM applied 2 h before XRT. CONCLUSIONS: Acute and late toxicity of skin and underlying soft tissues is not significantly increased after single-fraction radiotherapy in combination with GEM in the nude mice model.     

Comparison of activities dependent on glutathione S-transferase and cytochrome P-450 IA1 in cultured keratinocytes and reconstructed epidermal models

There is an increasing need for in vitro testing of compounds for topical application. Reconstructed epidermal models may provide a suitable and relevant model for screening compounds that may affect the activities of phase I and II enzymes involved in epidermal detoxification. In this study, we measured the activity of a phase I enzyme, cytochrome P450 IA1, i.e. 7-ethoxyresorufin-O-deethylase (EROD) and 7-ethoxycoumarin-O-deethylase (ECOD) activities, and that of a phase II enzyme, glutathione S-transferase (GST). The enzyme activities were determined in cultured keratinocytes, reconstructed epidermal models and samples of human epidermis or hair follicle. EROD activity was detected in cultured keratinocytes and was induced by 3-methylcholanthrene (3-MC) and beta-naphthoflavone. The level of induction increased with increasing confluence. Induced EROD activity could be inhibited by clotrimazole in a dose-dependent manner. However, EROD activity was not detected in either hair follicles or untreated epidermal models but could be induced by 3-MC. The ability to induce EROD activity in epidermal models was batch dependent, and clotrimazole was able to inhibit the induced EROD activity. ECOD activity was detected in untreated models and paralleled EROD activity. GST activity was detected in cultured keratinocytes and all epidermal models. GST activity in models was equal or higher than the activity in epidermal samples. Reconstructed skin models may be useful to study the effects of non-water-soluble topical formulations on xenobiotic metabolism.     

NAD(P)H:quinone reductase activity in human epidermal keratinocytes and reconstructed epidermal models

Reconstructed epidermal models may provide a suitable and relevant model for screening compounds such as quinones, which affect the activities of phase I and II enzymes involved in epidermal detoxification. Reconstructed epidermis may also allow the study of the metabolism of topically applied compounds by the phase I and II enzymes. We demonstrate that NAD(P)H:quinone reductase (NQR) activity is present in three different types of reconstructed epidermal models and that levels vary depending on the type of model. We also determined the inter- and intrabatch variability and demonstrate that NQR activity can be significantly inhibited by dicumarol treatment. The NQR activity in reconstructed epidermis is similar to that in human epidermis and lower than in cultured keratinocytes. Therefore reconstructed epidermis is a more suitable model for testing the effects of topically applied compounds on NQR activity or the metabolism of the compound by NQR.     

Altered host plant volatiles are proxies for sex pheromones in the gall wasp Antistrophus rufus

We describe a previously uncharacterized function for changes in plant chemistry induced by phytophagous insects: to provide cues for mate location. Larvae of the gall wasp Antistrophus rufus Gillette (Hymenoptera: Cynipidae) feed within inconspicuous galls inside the flowering stems of the prairie perennials Silphium laciniatum L. and Silphium terebinthinaceum Jacquin (Asteraceae). Adult male A. rufus emerge before females and are challenged with locating mates that are sequestered within dead plant stems that occur in a matrix of dead vegetation. Allozyme studies revealed complete reproductive isolation between wasp subpopulations in the two plant species. In laboratory bioassays, males responded only to their natal plant species, antennating the stem surface. Males from S. laciniatum also responded to hexane extracts of S. laciniatum stems, and extracts contained much higher concentrations of monoterpenes (alpha-pinene, beta-pinene, and camphene) than did S. terebinthinaceum. Ratios of "+" and "-" enantiomers of alpha- and beta-pinene approximated 50:50 for nongalled S. laciniatum stems but strongly differed from 50:50 in galled stems, with "+" and "-" enantiomers strongly dominant in different plants. In bioassays, male wasps from S. laciniatum responded to a synthetic blend of the monoterpenes in enantiomeric ratios characteristic of galled stems. Male A. rufus rely entirely on olfaction to locate females within stems in a complex prairie habitat, and gall wasps themselves apparently influence the plant to modify ratios of monoterpene enantiomers. These plant volatiles serve as a signal for males, acting as a sex pheromone proxy for females concealed within plant tissues.     

Effectiveness of rehabilitation with musculoskeletal diseases

Multidisciplinary treatment focusing on impairments, activities and participation are an important component within the therapeutic regimen in musculoskeletal conditions. In Germany, for more than 95% of the patients multidisciplinary treatment is provided as inpatient rehabilitation. According to the results of a study from the Netherlands, inpatient rehabilitation is superior to usual care in terms of decreasing disease activity and improving emotional well-being in rheumatoid arthritis. Another randomized, controlled study gives evidence that rehabilitation is more effective as compared to usual care in ankylosing spondylitis. In patients suffering from fibromyalgia, after inpatient rehabilitation, symptoms improve significantly and this is true even one year after discharge. The results of a quality management project financed by the German health insurance and including several thousand patients with musculoskeletal diseases show an improvement in physical and emotional dimensions of health status at discharge and after a six month follow-up. Recent studies comparing inpatient with outpatient rehabilitation in patients with musculoskeletal diseases provide information that both forms are equally effective. Taking into account the high number of inpatient rehabilitation procedures in Germany, more outcomes research is required urgently.     

Postmastectomy Electron-Beam-Rotation Irradiation in Locally Advanced Breast Cancer

BACKGROUND: Different radiotherapy techniques are used for postmastectomy irradiation. We review the results with the electron-beam-rotation technique in advanced breast cancer patients. Main endpoint was local tumor control. PATIENTS AND METHODS: From 1990 to 1998 119 patients with adverse pathology features (pT3 17% of patients, pT4 42%, multicentricity 36%, pN >/= 3 positive nodes and/or pN1biii 81%, close margins 30%) underwent electron-beam-rotation irradiation of the chest wall with daily fractions of 2.0-2.5 Gy per day to 50 Gy total dose after modified radical mastectomy and axillary lymph node dissection. A local boost of 10 Gy and/or irradiation of locoregional lymph nodes were applied depending on the completeness of resection and lymph node involvement. RESULTS: After a median follow-up of 73 months for patients at risk the 5-year local tumor control, local tumor control first event, disease-free, and overall survival were 82%, 92%, 57%, and 63% (Kaplen Meier analysis), respectively. Significant predictors of poor local tumor control were maximal tumor diameter >/= 5 cm (p = 0.01), "close margins" or residual tumor (p < 0.01), four or more involved axillary lymph nodes (p = 0.02), two or more involved lymph node levels (p = 0.04), negative estrogen receptor status (p = 0.03), and high-grade histopathology (GIIb-III, p < 0.01). The subgroup analysis showed a high local failure rate of 37% for high-grade (GIIb-III) and estrogen receptor negative tumors, whereas no local recurrence was found in low-grade (GI-Iia) and receptor positive tumors (p = 0.01). The multivariate analysis revealed maximal tumor diameter >/= 5 cm, four or more involved axillary lymph nodes and high-grade histopathology (GIIb-III) as independent predictors of poor local tumor control. CONCLUSION: In high-risk breast cancer patients postmastectomy irradiation with the electron-beam-rotation technique is an effective therapy, resulting in a 5-year local failure rate of 8%. Intensified local therapy needs further investigation in subgroups of patients with additional risk factors.     

The membrane targeted apoptosis modulators erucylphosphocholine and erucylphosphohomocholine increase the radiation response of human glioblastoma cell lines in vitro

Cervical cancer continues to be a significant health burden worldwide. Globally, the majority of cancers are locally advanced at diagnosis; hence, radiation remains the most frequently used therapeutical modality. Currently, the value of adding cisplatin or cisplatin-based chemotherapy to radiation for treatment of locally advanced cervical cancer is strongly supported by randomized studies and meta-analyses. Nevertheless, despite these significant achievements, therapeutic results are far from optimal; thus, novel therapies need to be assayed. A strategy currently being investigated is the use of newer radiosensitizers alone or in combination with platinum compounds. In the present work, we present preclinical information on known and newer cytotoxic agents as radiosensitizers on cervical cancer models, as well as the clinical information emanating from early phase trials that incorporate them to the cervical cancer management. In addition, we present the perspectives on the combined approach of radiation therapy and molecular target-based drugs with proven radiosensitizing capacity.     

Immunomagnetic enrichment and detection of micrometastases in colorectal cancer: correlation with established clinical parameters.

PURPOSE: Micrometastatic disease in bone marrow is of prognostic significance in colorectal cancer patients. However, detection rates of standard immunocytology are relatively low. We used magnetic activated cell sorting (MACS), a highly sensitive method, to increase detection rates and correlated the presence of cytokeratin (CK)-expressing cells with clinical parameters. PATIENTS AND METHODS: Bone marrow was obtained from 51 consecutive patients with newly diagnosed colorectal adenocarcinoma who underwent primary surgery and 18 control subjects. International Union Against Cancer (UICC) stage I disease was diagnosed in 11 patients, stage II disease was diagnosed in 14 patients, stage III disease was diagnosed in 12 patients, and stage IV disease was diagnosed in 14 patients. CK-positive cells were enriched and stained with magnetically labeled CAM 5.2 antibodies directed to CK 7 and 8. RESULTS: CK-positive cells were found in 33 (65%) patients and were absent in 18 (35%). Four of 11 (36%) patients with UICC stage I disease, nine of 14 (64%) with stage II diease, eight of 12 (67%) with stage III disease, and 12 of 14 (86%) with stage IV disease were CK-positive. Epithelial cells were more frequently found in pT3/4 (72%) than in pT1/2 (36%) tumors (P =.026), but there was no difference for lymph node status. CK-positive patients had a higher chance for elevated carcinoembryonic antigen (85% v 15%, P = NS) and CA 19-9 levels (92% v 8%, P =.019). There were no significant differences in CA 72-4, sex, age, tumor grading, or tumor localization regarding the presence of CK-positive cells. All control subjects were CK-negative. CONCLUSION: In searching for micrometastases in colorectal cancer patients, we have achieved high detection rates by using MACS. The presence of these cells correlated significantly with tumor stage, tumor extension, and the tumor marker CA 19-9.     

Untersuchungen zu Schwangerschaft und Subfekundität. Deutscher Anteil der EG-Studie

Ohne Zusammenfassung