Composition of PLGA and PEI/DNA nanoparticles improves ultrasound-mediated gene delivery in solid tumors in vivo

The goal of this study was to enhance gene delivery and tumor cell transfection in vivo by using a combination of ultrasonication with complex nanoparticles consisting of two types of nanoparticles: PEI/DNA β-gal plasmid with highly positive zeta-potential and air-filled poly (lactic-co-glycolic acid) (PLGA) particles (with negative zeta-potential) manufactured in our laboratory. The PLGA/PEI/DNA nanoparticles were a colloid with positive zeta-potential and injected i.v. in nude mice with DU145 human prostate tumors. We found that the combination of PLGA/PEI/DNA nanoparticles with ultrasonication substantially enhanced tumor cell transfection in vivo. The overexpression of β-gal gene was evaluated histochemically and by Western blot analysis. At least an 8-fold increase of the cell transfection efficacy was obtained in irradiated tumors compared to non-irradiated controls, while little to no cell death was produced by ultrasonication.     

Apolipoprotein-mediated transport of nanoparticle-bound drugs across the blood-brain barrier

Recent studies have shown that drugs that are normally unable to cross the blood-brain barrier (BBB) following intravenous injection can be transported across this barrier by binding to poly(butyl cyanoacrylate) nanoparticles and coating with polysorbate 80. However, the mechanism of this transport so far was not known. In the present paper, the possible involvement of apolipoproteins in the transport of nanoparticle-bound drugs into the brain is investigated. Poly(butyl cyanoacrylate) nanoparticles loaded with the hexapeptide dalargin were coated with the apolipoproteins AII, B, CII, E, or J without or after precoating with polysorbate 80. In addition, loperamide-loaded nanoparticles were coated with apolipoprotein E alone or again after precoating with polysorbate 80. After intravenous injection to ICR mice the antinociceptive threshold was measured by the tail flick test. Furthermore, the antinociceptive threshold of polysorbate 80-coated dalargin-loaded nanoparticles was determined in ApoEtm1Unc and C57BL/6J mice. The results show that only dalargin or loperamide-loaded nanoparticles coated with polysorbate 80 and/or with apolipoprotein B or E were able to achieve an antinociceptive effect. This effect was significantly higher after polysorbate-precoating and apolipoprotein B or E-overcoating. With the apolipoprotein E-deficient ApoEtm1Unc mice the antinociceptive effect was considerably reduced in comparison to the C57BL/6J mice. These results suggest that apolipoproteins B and E are involved in the mediation of the transport of drugs bound to poly(butyl cyanoacrylate) nanoparticles across the BBB. Polysorbate 80-coated nanoparticles adsorb these apolipoproteins from the blood after injection and thus seem to mimic lipoprotein particles that could be taken up by the brain capillary endothelial cells via receptor-mediated endocytosis. Bound drugs then may be further transported into the brain by diffusion following release within the endothelial cells or, alternatively, by transcytosis.     

Irampanel Boehringer Ingelheim

The oxazole derivative, irampanel, a non-competitive AMPA receptor antagonist, is under development by Boehringer Ingelheim for the potential treatment of stroke [329079]. Phase I/IIa trials for stroke had been initiated by July 2000 [374144]. Phase II trials were ongoing in April 2001 [407163]; in April 2002, however, the drug did not appear on the company's research and development pipeline [446554], and a company spokesperson declined to confirm its current status [450591]. The compound was also originally under investigation for other neurological disorders, including epilepsy and pain [329079], although by October 1999, development was only ongoing for stroke [346080].     

Evolution of genomic diversity and sex at extreme environments: fungal life under hypersaline Dead Sea stress

We have found that genomic diversity is generally positively correlated with abiotic and biotic stress levels (1-3). However, beyond a high-threshold level of stress, the diversity declines to a few adapted genotypes. The Dead Sea is the harshest planetary hypersaline environment (340 g.liter-1 total dissolved salts, approximately 10 times sea water). Hence, the Dead Sea is an excellent natural laboratory for testing the "rise and fall" pattern of genetic diversity with stress proposed in this article. Here, we examined genomic diversity of the ascomycete fungus Aspergillus versicolor from saline, nonsaline, and hypersaline Dead Sea environments. We screened the coding and noncoding genomes of A. versicolor isolates by using >600 AFLP (amplified fragment length polymorphism) markers (equal to loci). Genomic diversity was positively correlated with stress, culminating in the Dead Sea surface but dropped drastically in 50- to 280-m-deep seawater. The genomic diversity pattern paralleled the pattern of sexual reproduction of fungal species across the same southward gradient of increasing stress in Israel. This parallel may suggest that diversity and sex are intertwined intimately according to the rise and fall pattern and adaptively selected by natural selection in fungal genome evolution. Future large-scale verification in micromycetes will define further the trajectories of diversity and sex in the rise and fall pattern.     

Immunohistochemical Markers for Prognosis of Ependymal Neoplasms

Intracranial ependymomas are the third most common primary brain tumor in children. Although clinical and histological criteria for ependymoma prognosis are recognized, studies have reported contradictory results. Prognostic significance based on immunohistochemistry of ependymomas has been reported in a few studies. One-hundred and twelve patients with intracranial ependymomas were examined retrospectively for immuno-expression of various tumor-associated antigens and apoptosis. The results demonstrated significant preponderance of expression of the tenascin, vascular endothelial growth factor protein (VEGF), epidermal growth factor (EGFR) and p53 protein in high-grade tumors. Also high-grade ependymomas revealed more prominent labeling indices (LI) for proliferative marker Ki-S1 and apoptotic index (AI), and lower LI for cyclin-dependent kinase inhibitors p27/Kip1 and p14ARF. For low-grade ependymomas the progression-free survival time (PFS) was found to be significantly shorter for Ki-S1 LI>5%, and for tenascin, VEGF and EGFR positivity. For high-grade ependymomas PFS was found to be significantly reduced for p27 LI<20%, p14ARF LI<10%, for p53 positivity, and for AI<1%. The CART modeling process exhibited five final groups of ependymoma patients (1) low-grade and tenascin-negative; (2) low-grade and tenascin-positive; (3) high-grade and p53-negative with p14 LI>0%; (4) high-grade with combination of either p53 positivity and p14 LI>10% or p53 negativity and p14 LI<10%; (5) high-grade and p53-positive with p14 LI<10%. In summary, some immunohistochemical variables were found to be the strong predictors of ependymoma recurrence and they seem to be useful for assessing individual tumor prognosis in routinely processed biopsy specimens together with tumor grade. For histologically benign ependymomas immunohistochemical study should be focused on Ki-S1, tenascin, EGFR and VEGF evaluation, whereas p53 expression and number of p27, p14 and ISEL-positive nuclei will be of value in determining PFS from high-grade ependymomas.     

Farm exposures,parental occupation,and risk of Ewing's sarcoma in Australia: a national case-control study

Objective: It has been suggested that parental occupation, particularly farming, increased the risk of Ewing's sarcoma in the offspring. In a national case–control study we examined the relationship between farm and other parental occupational exposures and the risk of cancer in the offspring. Methods: Cases were 106 persons with confirmed Ewing's sarcoma or peripheral primitive neuroectodermal tumor. Population-based controls (344) were selected randomly via telephone. Information was collected by interview (84% face-to-face). Results: We found an excess of case mothers who worked on farms at conception and/or pregnancy (odds ratio (OR) = 2.3, 95% confidence interval (CI) 0.5–12.0) and a slightly smaller excess of farming fathers; more case mothers usually worked as laborers, machine operators, or drivers (OR = 1.8, 95% CI 0.9–3.9). Risk doubled for those whose mothers handled pesticides and insecticides, or fathers who handled solvents and glues, and oils and greases. Further, more cases lived on farms (OR = 1.6, 95% CI 0.9–2.8). In the 0–20 years group, the risk doubled for those who ever lived on a farm (OR = 2.0, 95% CI 1.0–3.9), and more than tripled for those with farming fathers at conception and/or pregnancy (OR = 3.5, 95% CI 1.0–11.9). Conclusions: Our data support the general hypothesis of an association of Ewing's sarcoma family of tumors with farming, particularly at younger ages, who represent the bulk of cases, and are more likely to share etiologic factors.     

Dextromethorphan for the reduction of immediate and late postoperative pain and morphine consumption in orthopedic oncology patients: a randomized,placebo-controlled,double-blind study

BACKGROUND: Postoperative pain is mediated centrally by N-methyl-D-aspartate (NMDA) receptors. The beneficial effects of preincision oral dextromethorphan (DM), which is an NMDA antagonist, on postoperative pain and intravenous patient-controlled analgesia (IV-PCA) morphine (MO) consumption have been examined in patients undergoing surgery. The authors investigated 75 patients who underwent surgery for bone and soft tissue malignancies, in whom postoperative pain is more severe compared with patients who undergo general surgery. METHODS: Patients received placebo, DM 60 mg, or DM 90 mg (25 patients per group) before surgery and on each of the two following days in a randomized, double-blind, placebo-controlled manner. Postoperative IV-PCA MO was started when subjective pain intensity was >/= 4/10 (visual score) and lasted for 72 hours. Rescue drugs on demand were oral paracetamol or dipyrone. RESULTS: The patients in the DM60 and DM90 groups similarly experienced 50-80% less pain (P < 0.01) compared with patients in the placebo group, both immediately and up to 3 days postoperatively, as well as a 50% reduction in the estimated overall maximal pain intensity (P < 0.01). Both DM groups consumed 50-70% less MO than the nonmedicated individuals in the placebo group (P < 0.01), and their demand for rescue drugs on the first postoperative day also was significantly lower (P < 0.01). Patients in the DM groups also were sedated less ( approximately 70%; P < 0.01). There were no differences among the groups in terms of when the patients left their beds, when they were discharged home, or the number of overall side effects. CONCLUSIONS: DM is associated with reduced pain intensity, sedation, and analgesic requirements, even in patients undergoing surgery for bone and soft tissue malignancies. A 3-day DM administration neither increased the incidence of side effects nor accelerated ambulation and discharge home.     

Brachytherapy of glioblastoma recurring in previously irradiated territory: predictive value of tumor volume

PURPOSE: To evaluate the impact of tumor volume on survival of patients reirradiated with (192)Ir for recurrent glioblastoma. METHODS AND MATERIALS: Between 1993 and 1997, 42 patients with recurrent glioblastomas (29 males and 13 females, age 18-69 years, median age 49) were treated with (192)Ir implantation. Previous treatments included surgery, external beam radiotherapy, and chemotherapy. Maximum diameter of the recurrent tumor was 1.2-10.1 cm (median: 5.7 cm) and tumor volume was 1.6-122 cm(3) (median: 23 cm(3)). Karnofsky performance status score was 50-100 (median: 80). Brachytherapy dose was 40-60 Gy. RESULTS: Probability of overall survival was 80% at 6 months, 48% at 1 year, and 11% at 2 years. Median survival was 50 weeks. Univariate analysis showed that both tumor volume (T < or T > or = 30 cm(3)) and Karnofsky performance status score were significant predictors of survival. Multivariate analysis showed that smaller tumor volumes were associated with a higher probability of survival (p < 0.001). CONCLUSION: Tumor volume less than 30 cm(3) was associated with a higher probability of, and quality of, survival than larger lesions for patients reirradiated by brachytherapy for recurrent glioblastoma.     

Development of Immunosorbents for apoB-Containing Lipoproteins Apheresis

Abstract: Three types of sorbents were developed for the specific removal of atherogenic apoB-containing low-density lipoprotein (LDL) and lipoprotein LDL(a) (Lp[a])from human plasma. Two sorbents contained monospecific sheep polyclonal or mouse monoclonal antibodies against human apoprotein B-100. The third one was intended for specific removal of Lp(a) and contains sheep antibodies against human Lp(a). Thirty patients were treated for up to 9 years by LDL apheresis with anti-LDL immunosorbents. A pilot study of Lp(a) apheresis with 3 patients was conducted during 3 years. The results showed that extracorporeal immunosorption is safe and effective for lowering LDL and Lp(a). These procedures may be used both for metabolic investigations and for studies on possible regression of atherosclerosis.     

Polymer genomics: shifting the gene and drug delivery paradigms.

Pluronic, the A-B-A amphiphilic block copolymers of poly(ethylene oxide) and poly(propylene oxide), can up-regulate the expression of selected genes in cells and alter genetic responses to antineoplastic agents in cancer. Two key new findings are discussed in relation to current drug and gene delivery strategies. First, these block copolymers alone and in combination with a polycation, polyethyleneimine, can up-regulate the expression of reporter genes in stably transfected cells. This underscores the ability of selected synthetic polymers to enhance transgene expression through a mechanism that augments improved DNA delivery into a cell. Second, although, when used alone, Pluronic is "genetically benign," when combined with an antineoplastic agent, doxorubicin, it drastically alters pharmacogenomic responses to this agent and prevents the development of multidrug resistance in breast cancer cells. Collectively, these studies propose the need for a thorough assessment of pharmacogenomic effects of polymer therapeutics to maximize the clinical outcomes and understand the pharmacological and toxicological effects of polymer-based drugs and delivery systems.