Antagonism of endogenous growth hormone-releasing hormone (GHRH) leads to reduced proliferation and apoptosis in MDA231 breast cancer cells

GHRH, in addition to stimulating the release of growth hormone (GH) from the pituitary, is a trophic factor for pituitary somatotrophs. Growth hormone-releasing hormone is also expressed in the gonads, gastrointestinal tract, pancreas, thymus, and lymphocytes, as well as in tumors of the pancreas, lung, central nervous system, and breast. Since GHRH has mitogenic effects, we examined the hypothesis that GHRH is an autocrine/paracrine growth factor in neoplastic breast tissue. The effect of disrupting endogenous GHRH on cell growth and apoptosis of MDA231 cells was examined through the use of a competitive GHRH antagonist, [N-acetyl-Tyr1, D-Arg2] fragment 1–29Amide (GHRHa). Cell proliferation was determined by direct cell counting and tritiated thymidine incorporation. Apoptosis was analyzed by examination of DNA laddering and nuclear condensation. GHRHa resulted in a dose-dependent, transient, and reversible decrease in cell number, proliferation rate, and tritiated thymidine uptake. Conversely, GHRHa led to a marked and dose-dependent increase in both DNA laddering and nuclear condensation. These results indicate that disruption of endogenous GHRH action in MDA231 cells results in both decreased cellular proliferation and increased apoptosis. Taken together, the findings suggest that endogenous GHRH acts as an autocrine/paracrine factor in the regulation of growth of at least some breast cancer cell types.     

Inhibition of gene expression and growth by antisense peptide nucleic acids in a multiresistant beta-lactamase-producing Klebsiella pneumoniae strain

Klebsiella pneumoniae causes common and severe hospital- and community-acquired infections with a high incidence of multidrug resistance. The emergence and spread of beta-lactamase-producing K. pneumoniae strains highlight the need to develop new therapeutic strategies. In this study, we developed antisense peptide nucleic acids (PNAs) conjugated to the (KFF)(3)K peptide and investigated whether they could mediate gene-specific antisense effects in K. pneumoniae. No outer membrane permeabilization was observed with antisense PNAs when used alone. Antisense peptide-PNAs targeted at two essential genes, gyrA and ompA, were found to be growth inhibitory at concentrations of 20 muM and 40 muM, respectively. Mismatched antisense peptide-PNAs with sequence variations of the gyrA and ompA genes when used as controls were not growth inhibitory. Bactericidal effects exerted by peptide-anti-gyrA PNA and peptide-anti-ompA PNA on cells were observed within 6 h of treatment. The antisense peptide-PNAs specifically inhibited expression of DNA gyrase subunit A and OmpA from the respective targeted genes in a dose-dependent manner. Both antisense peptide-PNAs cured IMR90 cell cultures that were infected with K. pneumoniae (10(4) CFU) in a dose-dependent manner without any noticeable toxicity to the human cells.     

The use of Ginkgo biloba for the prevention of chemotherapy-related cognitive dysfunction in women receiving adjuvant treatment for breast cancer, N00C9

Purpose

Patients undergoing treatment for cancer often report problems with their cognitive function, which is an essential component of health-related quality of life. Pursuant to this, a two-arm randomized, placebo-controlled, double-blind, phase III clinical trial was conducted to evaluate Ginkgo biloba (EGB 761) for the prevention of chemotherapy-related cognitive dysfunction in patients with breast cancer.

Methods

Previously chemotherapy naïve women about to receive adjuvant chemotherapy for breast cancer were randomized to receive 60 mg of EGB 761 or a matching placebo twice daily. The study agent was to begin before their second?cycle of chemotherapy and to be taken throughout chemotherapy and 1 month beyond completion. The primary measure for cognitive function was the High Sensitivity Cognitive Screen (HSCS), with a secondary measure being the Trail Making Tests (TMT) A and B. Subjective assessment of cognitive function was evaluated by the cognitive subscale of the Perceived Health Scale (PHS) and the Profile of Mood States (POMS). Data were collected at baseline and at intervals throughout and after chemotherapy, up to 24 months after completion of adjuvant treatment. The primary statistical analysis included normalized area under the curve (AUC) comparisons of the HSCS, between the arms. Secondary analyses included evaluation of the other measures of cognition as well as correlational analyses between self-report and cognitive testing.

Results

One hundred and sixty-six women provided evaluable data. There were no significant differences in AUC up to 12 months on the HSCS between arms at the end of chemotherapy or at any other time point after adjuvant treatment. There were also no significant differences in TMT A or B at any data point. Perceived cognitive functions, as measured by the PHS and confusion/bewilderment subscale of the POMS, were not different between arms at the end of chemotherapy. There was also little correlation between self-reported cognition and cognitive testing. No differences were observed in toxicities per Common Terminology Criteria for Adverse Events (CTCAE) assessment between Ginkgo biloba and placebo throughout the study; however, after chemotherapy, the placebo group reported worse nausea (p?=?.05).

Conclusion

This study did not provide any support for the notion that Ginkgo biloba, at a dose of 60 mg twice a day, can help prevent cognitive changes from chemotherapy. These analyses do provide data to further support the low associations between patients' self-report of cognition and cognitive performance, based on more formal testing.     

Phase II trial of subcutaneous interferon followed by intravenous hybrid bolus/continuous infusion interleukin-2 in the treatment of renal cell carcinoma: final results of Cancer Biotherapy Research Group 95-09

OBJECTIVE: We conducted a phase II trial in metastatic renal cell cancer of outpatient subcutaneous (s.c.) interferon-alpha2b (IFN), followed by an inpatient hybrid schedule of bolus and continuous interleukin-2 (IL- 2). METHODS: Treatment consisted of monthly IFN 10 MU/m(2) s.c. for 4 consecutive days, followed by 36 MIU/m(2) bolus IL-2, then 72-hour continuous intravenous (i.v.) infusion of 18 MIU/m(2) IL-2 per day. Between May 1997 and June 2000, 25 men and 11 women enrolled, with a median age of 57 years (range, 42-77), including 9 patients over 65. Prior treatment included nephrectomy (31), radiation (8), biotherapy (7), and chemotherapy (4). Sites of disease included 26 lung, 13 lymph node, 9 bone, 8 liver, 4 kidney, and 4 adrenal locations. Patients received an average of 3.1 treatment cycles (range, 1-6). RESULTS: There was 1 complete and 3 partial responses, for a response rate of 11% (3% to 27%; 95% confidence interval [CI]); 40% had stable disease. Median failure-free survival was 2.5 months; median overall survival was 15.0 months. The 1-, 2-, and 5-year survival rates were 53%, 30%, and 12%, respectively. Only 8 patients required a reduction in IL-2 dose. The most frequent grade 3 or 4 toxicities were 11% fatigue, 9% renal insufficiency, and 7% hypotension. CONCLUSIONS: Response and survival rates were similar to those seen in other multicenter trials using inpatient high-dose IL-2.     

A possible pH-controlled drug delivery system based on a derivative of the polysaccharide scleroglucan

Four carboxylated derivatives of scleroglucan have been obtained by oxidation, to different extents, of the glucopyranose side chains of the natural polysaccharide. The diffusion of model molecules through aqueous solutions of these new products was measured at various pH values. The reversible pH induced sol-gel transition of some of the polyelectrolyte solutions tested effects a remarkable variation in the diffusion rate of the permeating species; in this sense the most interesting polysaccharide appears to be the product with 70% oxidized glucopyranose moieties. The behaviour of scleroglucan and its derivatives has been compared with that of carboxymethylcellulose and the mechanism involved in drug permeation and release discussed. The possible application of one of the new products in controlled release formulations for oral use is also reported.     

Design and synthesis of N-[(4-methoxyphenoxy)carbonyl]-N-[[4-[2-(5- methyl-2-phenyl-4-oxazolyl)ethoxy]phenyl]methyl]glycine [Muraglitazar/BMS-298585], a novel peroxisome proliferator-activated receptor alpha/gamma dual agonist with efficacious glucose and lipid-lowering activities

Muraglitazar/BMS-298585 (2) has been identified as a non-thiazolidinedione PPAR alpha/gamma dual agonist that shows potent activity in vitro at human PPARalpha (EC(50) = 320 nM) and PPARgamma(EC(50) = 110 nM). Compound 2 shows excellent efficacy for lowering glucose, insulin, triglycerides, and free fatty acids in genetically obese, severely diabetic db/db mice and has a favorable ADME profile. Compound 2 is currently in clinical development for the treatment of type 2 diabetes and dyslipidemia.     

Evidence of cellular immune activation in children with opsoclonus-myoclonus: cerebrospinal fluid neopterin

To evaluate cellular immune activation in opsoclonus-myoclonus syndrome, we measured the inflammatory marker neopterin in the cerebrospinal fluid of 16 children with opsoclonus-myoclonus and neuroblastoma, 24 children with opsoclonus-myoclonus but no tumor, and 19 age-matched controls. The mean concentration in opsoclonus-myoclonus was 2.3-fold higher than in controls (P = .008). Neopterin was greatly elevated in four of the most neurologically severe cases, up to 8.3-fold above the highest control level. Thirteen of the 40 children with opsoclonus-myoclonus but no controls had a neopterin concentration >2 SD above the control mean (P = .005). In this high neopterin subgroup, neurologic severity was significantly greater and the duration of neurologic symptoms was less. In 16 children re-examined on immunotherapy, including adrenocorticotropic hormone (ACTH) combination therapy, treatment was associated with a significant reduction in both neopterin and neurologic severity. Neopterin did not differ significantly between the tumor and non-tumor opsoclonus-myoclonus etiologies. No abnormalities of tetrahydrobiopterin were found. Although cerebrospinal fluid neopterin lacked the sensitivity to be a biomarker of disease activity in opsoclonus-myoclonus, elevated concentrations do support a role for T-cell activation and cell-mediated immunity in its pathophysiology.     

The role of Galectin-1 in the interaction between chondrocytes and a lactose-modified chitosan

Evidences for the involvement of the Galectin-1 in the interaction of pig chondrocytes with a lactose-modified chitosan, namely Chitlac, are reported. The Chitlac glycopolymer has been shown to promote pig chondrocyte aggregation and to induce extracellular matrix production. Highly pure Galectin-1 was obtained from pig spleen by affinity chromatography and its identity was determined by ion spray mass spectrometry analysis of tryptic peptide fragments obtained after in-gel digestion. The complete sequence of pig Galectin-1 CDS was obtained by screening a pig EST database using human Galectin-1 sequence as template. The Galectin-1 cDNA was cloned into a pGEX-4T-1 expression vector and the recombinant protein was purified, characterized and used to produce a rabbit anti-serum. Recombinant Galectin-1 interacts in a dose-dependent manner with Chitlac as determined with ELISA assay. Expression level of galectin-1 gene, quantified by real-time PCR, was significantly higher in chondrocytes cultivated on Chitlac. In the same way, the presence of Chitlac stimulates secretion of Galectin-1 in culture medium that, by immunohistochemical analysis, revealed to be clustered on the surface of Chitlac-induced aggregates. These data indicate the role of Galectin-1 as a bridging agent between Chitlac and chondrocyte aggregates.