P2-11-10: Low Toll-Like Receptor 9 Expression Is Required for the Aggressive Behavior of Triple Negative Breast Cancer Cells in Hypoxia

Toll-like receptor-9 (TLR9) is a cellular DNA-receptor and a member of the innate immune system which is widely expressed in breast cancers. Although synthetic TLR9-ligands stimulate breast cancer cell invasion in vitro, through down-regulation of tissue inhibitor of matrix metalloproteinase-3 (TIMP-3), the role of this protein in breast or other cancer pathophysiology is unclear. We discovered that low tumor TLR9 expression is associated with a significantly shortened breast cancer specific survival among patients with triple negative tumors, but not among those with ER+ tumors. We further discovered that hypoxia induces TLR9 expression in breast cancer cells in vitro and in vivo. Although the triple negative TLR9 siRNA MDA-MB-231 breast cancer cells (with lower TLR9 expression) were less invasive than control siRNA cells in normoxia, these cells became highly aggressive in hypoxia and they formed significantly larger tumors than corresponding control cells in an orthotopic model in vivo. Further in vitro experiments revealed that the removal of TLR9 expression through siRNA significantly potentiated the hypoxia-induced invasive capacity of the triple negative MDA-MB-231 cells, but not that of the ER+ T47-D cells. Low TLR9 expression in hypoxia resulted also in complete disappearance of TIMP-3 in the MDA-MB-231 cells, but not in the ER+ T47-D cells. Taken together, these studies suggest that low TLR9 expression has different effects on the behavior of triple negative and ER+ breast cancer cells in hypoxia; triple negative cells become more invasive under these conditions, possibly through loss of endogenous invasion inhibitors, such as TIMP-3. Furthermore, these studies suggest that low TLR9 expression in triple negative breast cancers may serve as a novel prognostic factor and help characterize the group of patients that are at a high risk of relapse. Finally, our results suggest that any treatments or factors that lower TLR9 expression or induce hypoxia in residual or metastatic triple negative breast cancer cells, might actually induce their spread.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P2-11-10.

Spinal cord injury causes rapid osteoclastic resorption and growth plate abnormalities in growing rats (SCI-induced bone loss in growing rats)

Spinal cord injury causes severe bone loss. We report osteoclast resorption with severe trabecular and cortical bone loss, decreased bone mineral apposition, and growth plate abnormalities in a rodent model of contusion spinal cord injury. These findings will help elucidate the mechanisms of osteoporosis following neurological trauma.

INTRODUCTION

Limited understanding of the mechanism(s) that underlie spinal cord injury (SCI)-induced bone loss has led to few treatment options. As SCI-induced osteoporosis carries significant morbidity and can worsen already profound disability, there is an urgency to advance knowledge regarding this pathophysiology.

METHODS

A clinically relevant contusion model of experimental spinal cord injury was used to generate severe lower thoracic SCI by weight-drop (10 g x 50 mm) in adolescent male Sprague-Dawley rats. Body weight and gender-matched naïve (no surgery) rats served as controls. Bone microarchitecture was determined by micro-computed tomographic imaging. Mature osteoclasts were identified by TRAP staining and bone apposition rate was determined by dynamic histomorphometry.

RESULTS

At 10 days post-injury we detected a marked 48% decrease in trabecular bone and a 35% decrease in cortical bone at the distal femoral metaphysis by micro-CT. A 330% increase in the number of mature osteoclasts was detected at the growth plate in the injured animals that corresponded with cellular disorganization at the chondro-osseous junction. Appositional growth studies demonstrated decreased new bone formation with a mineralization defect indicative of osteoblast dysfunction.

CONCLUSIONS

Contusion SCI results in a rapid bone loss that is the result of increased bone resorption and decreased bone formation.

Fluoxetine treatment increases trabecular bone formation in mice

Mounting evidence exists for the operation of a functional serotonin (5-HT) system in osteoclasts and osteoblasts, which involves both receptor activation and 5-HT reuptake. In previous work we showed that the serotonin transporter (5-HTT) is expressed in osteoclasts and that its activity is required by for osteoclast differentiation in vitro. The purpose of the current study was to determine the effect of treatment with fluoxetine, a specific serotonin reuptake inhibitor, on bone metabolism in vivo. Systemic administration of fluoxetine to Swiss-Webster mice for 6 weeks resulted in increased trabecular BV and BV/TV in femurs and vertebrae as determined by micro-computed tomography (microCT). This correlated with an increase in trabecular number, connectivity, and decreased trabecular spacing. Fluoxetine treatment also resulted in increased volume in vertebral trabecular bone. However, fluoxetine-treated mice were not protected against bone loss after ovariectomy, suggesting that its anabolic effect requires the presence of estrogen. The effect of blocking the 5-HTT on bone loss following an LPS-mediated inflammatory challenge was also investigated. Subcutaneous injections of LPS over the calvariae of Swiss-Webster mice for 5 days resulted in increased numbers of osteoclasts and net bone loss, whereas new bone formation and a net gain in bone mass was seen when LPS was given together with fluoxetine. We conclude that fluoxetine treatment in vivo leads to increased bone mass under normal physiologic or inflammatory conditions, but does not prevent bone loss associated with estrogen deficiency. These data suggest that commonly used anti-depressive agents may affect bone mass.

Washing of stored red blood cells by an autotransfusion device before transfusion

BACKGROUND AND OBJECTIVES

The use of an autotransfusion device to wash blood of the incision site is increasing. After washing, this blood is retransfused without side effects caused by activated plasma factors and cell release products. This procedure could be extended to washing of donor blood, which may be particularly useful for red blood cells (RBCs) stored for more than 4 weeks that contain high concentrations of free haemoglobin, potassium, lactate and other metabolites. It is not known whether stored RBCs can withstand the cell washing procedure with the use of an autotransfusion device, while keeping their primary functions intact. The objective of this study was to determine the quality of RBCs, after cell washing in comparison to untreated RBCs.

MATERIALS AND METHODS

RBCs were studied in terms of integrity (free haemoglobin), stored energy (2,3-diphosphoglycerate, adenosine triphosphate), metabolites (lactate, potassium) and physical characteristics (osmotic resistance, aggregability, deformability).

RESULTS

After washing, free lactate and potassium were significantly reduced as compared to the levels before washing. The osmotic resistance of RBCs slightly improved, whereas aggregation capacity reduced after washing. Fifteen per cent of haemoglobin was lost during washing. The deformability and free haemoglobin levels remained unchanged.

CONCLUSION

Washing stored blood before transfusion may be of benefit, because the waste products are effectively removed from the stored RBC.

Absorption, distribution, and transformation of TNT in higher plants

The ability of eight species of plants to assimilate 2,4,6-trinitrotoluene (TNT) was investigated. Glycine max (soybean), in particular, demonstrated rapid assimilation of high concentrations of this explosive. Penetration and localization of [1-(14)C]-TNT in plant root cells and leaves were studied via electron microscopic autoradiography. TNT was shown to be localized primarily on membrane structures involved in the transportation of nicotinamide coenzymes (membranes of endoplasmic reticulum, mitochondria, plastids). [1-(14)C]-TNT in roots was incorporated mainly in low-molecular-weight metabolites; however, in stems and leaves, the radiocarbon was incorporated in biopolymers. Enzymatic transformation of TNT in roots was studied, and it was found that degradation involved mainly nitroreductase acting on the TNT nitro groups. The process was intensified in the presence of electron donors--NADH and NADPH. Nitroreductase activity was revealed in root cell cytosol and expression was strongly induced by plant cultivation on TNT-containing media. Oxidation of [C(3)H(3)]TNT by peroxidase and phenoloxidase was also studied. In contrast to the strongly induced nitroreductase, levels of these enzymes changed very little with TNT addition. This suggests that the main pathway of TNT transformation in plant cells is nitro group reduction. A plant's nitroreductase activity and its ability to incorporate TNT from aqueous solutions were correlated in four plants that were studied. The results suggest that plant nitroreductase activity may serve as a good biochemical indicator of plants that can be used for phytoremediation of soils contaminated with TNT.

Expression of osteoprotegerin, receptor activator of NF-kappaB ligand (osteoprotegerin ligand) and related proinflammatory cytokines during fracture healing

Fracture healing is a unique biological process regulated by a complex array of signaling molecules and proinflammatory cytokines. Recent evidence for the role of tumor necrosis family members in the coupling of cellular functions during skeletal homeostasis suggests that they also may be involved in the regulation of skeletal repair. The expression of a number of cytokines and receptors that are of functional importance to bone remodeling (osteoprotegerin [OPG], macrophage colony-stimulating factor [M-CSF], and osteoprotegerin ligand [receptor activator of NF-kappaB ligand (RANKL)]), as well as inflammation (tumor necrosis factor alpha [TNF-alpha] and its receptors, and interleukin-1alpha [IL-1alpha] and -beta and their receptors) were analyzed over a 28-day period after the generation of simple transverse fractures in mouse tibias. OPG was expressed constitutively in unfractured bones and elevated levels of expression were detected throughout the repair process. It showed two distinct peaks of expression: the first occurring within 24 h after fracture and the second at the time of peak cartilage formation on day 7. In contrast, the expression of RANKL was nearly undetectable in unfractured bones but strongly induced throughout the period of fracture healing. The peak in expression of RANKL did not correlate with that of OPG, because maximal levels of expression were seen on day 3 and day 14, when OPG levels were decreasing. M-CSF expression followed the temporal profile of RANKL but was expressed at relatively high basal levels in unfractured bones. TNF-alpha, lymphotoxin-beta (LT-beta), IL-1alpha, and IL-1beta showed peaks in expression within the first 24 h after fracture, depressed levels during the period of cartilage formation, and increased levels of expression on day 21 and day 28 when bone remodeling was initiated. Both TNF-alpha receptors (p55 and p75) and the IL-1RII receptor showed identical patterns of expression to their ligands, while the IL-1R1 was expressed only during the initial period of inflammation on day 1 and day 3 postfracture. Both TNF-alpha and IL-1alpha expression were localized primarily in macrophages and inflammatory cells during the early periods of inflammation and seen in mesenchymal and osteoblastic cells later during healing. TNF-alpha expression also was detected at very high levels in hypertrophic chondrocytes. These data imply that the expression profiles for OPG, RANKL, and M-CSF are tightly coupled during fracture healing and involved in the regulation of both endochondral resorption and bone remodeling. TNF-alpha and IL-1 are expressed at both very early and late phases in the repair process, which suggests that these cytokines are important in the initiation of the repair process and play important functional roles in intramembraneous bone formation and trabecular bone remodeling.

Simple two-color array-based approach for mutation detection

The ability to analyze multiple polymorphic/mutation sites rapidly and accurately is pivotal in all areas of genetic analysis. We have applied single nucleotide primer extension (SNE) for detection of multiple point mutations in a micro-array format using two-color, fluorescent dye-tagged dideoxynucleoside triphosphate terminators (ddNTPs). The oligonucleotide primer ending one nucleotide short of the mutation site being probed is bound to the slide and single-base extended in place with two different Cy5/Cy3 dye-tagged terminators using solution-phase, locus-specific, single-stranded complementary templates generated by PCR from genomic DNA. The composite fluorescence produced contains peaks of distinct wave lengths corresponding to each Cy dye-tagged terminator incorporated, resulting in a fluorescent 'fingerprint' for each DNA target. DNA polymerase-catalyzed incorporation of Cy dye-tagged dideoxynucleoside triphosphates was dependent on the particular dyes, the specific ddNTP, the DNA target concentration, sequence of the template, on-slide temperature cycling and washing conditions. Results from analysis of mutations in the human hemochromatosis and connexin 26 genes show that this approach has several advantages over existing methods and is simple, rapid, robust, cost effective and accurate with potential applications in many areas of genetic analysis.

Tyrosine kinases activate store-mediated Ca2+ entry in human platelets through the reorganization of the actin cytoskeleton

We have recently reported that store-mediated Ca(2+) entry in platelets is likely to be mediated by a reversible trafficking and coupling of the endoplasmic reticulum with the plasma membrane, a model termed 'secretion-like coupling'. In this model the actin cytoskeleton plays a key regulatory role. Since tyrosine kinases have been shown to be important for Ca(2+) entry in platelets and other cells, we have now investigated the possible involvement of tyrosine kinases in the secretion-like-coupling model. Treatment of platelets with thrombin or thapsigargin induced actin polymerization by a calcium-independent pathway. Methyl 2,5-dihydroxycinnamate, a tyrosine kinase inhibitor, prevented thrombin- or thapsigargin-induced actin polymerization. The effects of tyrosine kinases in store-mediated Ca(2+) entry were found to be entirely dependent on the actin cytoskeleton. PP1, an inhibitor of the Src family of proteins, partially inhibited store-mediated Ca(2+) entry. In addition, depletion of intracellular Ca(2+) stores stimulated cytoskeletal association of the cytoplasmic tyrosine kinase pp60(src), a process that was sensitive to treatment with cytochalasin D and PP1, but not to inhibition of Ras proteins using prenylcysteine analogues. Finally, combined inhibition of both Ras proteins and tyrosine kinases resulted in complete inhibition of Ca(2+) entry, suggesting that these two families of proteins have independent effects in the activation of store-mediated Ca(2+) entry in human platelets.

Hemispheric contributions to pragmatics

Twenty-seven patients with right-hemisphere damage (RBD) and thirty-one patients with left-hemisphere damage (LBD) received a new pragmatics battery in Hebrew consisting of two parts: (1) comprehension and production of basic speech acts (BSAs), including tests of assertions, questions, requests, and commands, and (2) comprehension of implicatures, including implicatures of quantity, quality, relevance, and manner. Each test had a verbal and a nonverbal version. Patients also received Hebrew versions of the Western Aphasia Battery and of the Right Hemisphere Communication Battery. Both LBD and RBD patients were impaired relative to controls but did not differ from each other in their overall scores on BSAs and on Implicatures when scores were corrected by aphasia and neglect indices. There was a systematic localization of BSAs in the left hemisphere (LH) but not in the right hemisphere (RH). There was poor localization of Implicatures in either hemisphere. In LBD patients, BSAs were associated with language functions measured with the WAB, suggesting the radical possibility that the classic localization of language functions in aphasia is influenced by the localization of the BSAs required by aphasia language tests. Both BSAs and implicatures show greater functional independence from other pragmatic, language and cognitive functions in the RBD than in the LBD patients. Thus, the LH is more likely to contain an unmodular domain-nonspecific set of central cognitive mechanisms for applying means-ends rationality principles to intentional activity.

Perioperative extracorporeal membrane oxygenation for tracheal reconstruction in congenital tracheal stenosis

The management of a critical airway in infants and toddlers with congenital tracheal stenosis (CTS) continues to be an enormous challenge to the surgeon. Until recently, this condition often proved fatal. Improvements in surgical techniques, anesthetic management, and postoperative critical care have resulted in successful outcomes in children not long ago considered untreatable. However, issues such as the best operative approach and the optimal perioperative management are still unresolved. The diagnosis of CTS, often delayed, must be considered in any infant with stridor, wheezing, cyanosis, or recurrent episodes of pneumonia. Associated anomalies are the rule, including frequently vascular rings and rarely pulmonary agenesis. These defects can be repaired with conventional ventilatory support under cardiopulmonary bypass, or using extracorporeal membrane oxygenation (ECMO). We report our experience in which ECMO was used to support two patients with CTS during the perioperative period. ECMO proved to be both safe and practical, allowing unrushed, precise repair of the tracheal stenosis and providing brief postoperative support. Perioperative outcomes were excellent, although one of our patients died months after the repair. A review of the literature and our experience in which ECMO was used to provide cardiopulmonary support during repair of CTS showed uniformly successful perioperative outcomes.

Use of Toronto stentless porcine valve in patients with aortic dilation

One of the contraindications for a stentless aortic valve is dilation of the aorta such that the sinotubular ridge is more than 2 mm larger than the annulus. Since May of 1994, 134 patients have had their aortic valve replaced with St Jude Toronto SPV valves; of these, 38 patients have required sinotubular ridge reduction. This was done by using one or more pleats in the aorta between the commisural posts. There were 20 patients with one pleat, 12 patients with two pleats, 5 patients with three pleats, and 1 patient with four pleats. In addition, three Toronto SPV valves were used in patients with significant calcification in the native coronary sinuses. All of the valves have had trace or no aortic insufficiency and have not developed aortic insufficiency in follow-up evaluation. Mean gradients remain low (<10 mm Hg). These valves have been much more versatile than originally expected and can be used in patients with mild to moderate aortic dilation and calcification.

Effects of right- and left-hemisphere damage on understanding conversational implicatures

Processing of implicatures was examined in 27 right-brain-damaged (RBD) and 31 left-brain-damaged (LBD) stroke patients with focal lesions using a new implicatures battery (IB) as part of an exploration of the neural basis and modularity of natural language pragmatics. Following Grice, we sampled implicatures of Quantity, Quality, Relation, and Manner. Verbal implicatures consisted of two-sentence conversational vignettes which are literally problematic. Nonverbal implicatures consisted mostly of famous paintings that are literally problematic (e.g., Magritte's "Le Domain d'Arnheim"). The patient has to identify and solve the problem. To compare with performance on the IB, patients also received a Hebrew adaptation of Gardner and Brownell's Right Hemisphere Communication Battery, a new test of basic speech acts (verbal and nonverbal assertions, questions, requests, and commands), a Hebrew version of the Western Aphasia Battery, and standardized neuropsychological tests. Both LBD and RBD patients were significantly impaired in implicature processing relative to age-matched normal controls. In general, both patient groups showed weak correlations of implicatures with extents of lesions in left perisylvian language area or its right-hemisphere (RH) homolog. However, performance of LBD and RBD patients on the IB revealed different patterns of correlations with other pragmatic, language, and nonlanguage tests. In LBD patients, there was a greater association between performance on verbal and nonverbal implicatures and between performance on implicatures and basic speech acts than in RBD patients. Given the different modes in which right-and left-hemisphere (LH) damage affect the processing of conversational implicatures, it remains to be discovered how the two hemispheres interact to process natural language pragmatics in the normal brain in real time.

Substrate and inhibitor recognition of protein kinases: what is known about the catalytic subunit of phosphorylase kinase?

Although much can be learned about the specificity of protein kinases from studies with peptide substrates, the question remains, how do kinases recognize their three-dimensional protein substrates? Information derived from such studies provides further understanding of substrate recognition and can facilitate the design of specific protein kinase inhibitors. Phosphorylase kinase (PhK) catalyzes the phosphorylation of phosphorylase b (phos. b) to form the active phosphorylase a. No other protein kinase can duplicate this reaction. Why? To probe this question and establish what features in the protein are important for substrate binding and product release, mutants of phos. b have been studied. This report shows how mutations change the properties of the protein substrate and the ability of these mutants to be phosphorylated by PhK and other kinases. Action of protein kinases on their substrates is often regulated by autoinhibitory segments. The C-terminus of the catalytic gamma-subunit of PhK contains two inhibitory sites overlapping two calmodulin-binding regions. These two peptide segments resemble sequences in phos. b and may explain why peptides of these regions are potent inhibitors of PhK. We will show results with peptide inhibitors, using various expressed forms of the catalytic subunit, which describe their modes of interaction and mechanisms of inhibition. Metal ions can change molecular interactions. With PhK, Mn2+ facilitates the use of GTP as a phosphoryl group donor and greatly increases phosphorylation of a tyrosine residue in angiotensin II. This implies that the spatial arrangement of specificity determinants can be manipulated so that PhK can utilize other substrates.

Longitudinal assessment of play and adaptive behavior in young children with developmental disabilities

Deficits in appropriate play have been widely documented among children with developmental disabilities. However, there has been little research on the development of play or the relation between play and adaptive behavior in such children. The present study involved a longitudinal assessment of play and adaptive behavior among 13 preschool children with developmental disabilities. Children were assessed every 6 months over a 3-year period. Assessments included standardized ratings of adaptive behavior and videotape observations during unstructured free-play times in the preschool classroom. Adaptive behavior increased by almost one standard deviation from the first to the last round of data collection. Appropriate play was observed during approximately 20% of each 30-min observation and showed little overall change over 3 years of study. Observed play was primarily functional (57%) and exploratory (28%) with less constructive (5%) and pretend (10%) play. Adaptive behavior scores were not consistently correlated with the amount or type of play. The results suggest little overall relation between appropriate play and other major domains of adaptive behavior. Implications for play-based assessment and intervention in early childhood special education are discussed.

Chemical cross-linking of ethidium to DNA by glyoxal

Ethidium was found to be efficiently cross-linked to DNA by glyoxal. Kinetic studies showed that the rate of the cross-linking reaction is strongly dependent on the glyoxal concentration. Comparative studies using a series of phenanthridines and acridines showed that NH2 groups at both the 2 and 7 positions on the phenanthridine ring are necessary for efficient cross-linking. Studies using synthetic polydeoxynucleotides showed that the 2-amino group of guanine is absolutely required for cross-linking. Fluorescence contact energy transfer and relative viscosity experiments showed that the cross-linked drug remains intercalated into DNA. DNA gel electrophoresis and melting studies demonstrated that cross-linked ethidium does not dissociate the DNA double helix to single strands.

Rapid and long-term effects of PTH(1-34) on growth plate chondrocytes are mediated through two different pathways in a cell-maturation-dependent manner

The aims of this study were to clarify the role of cell maturation stage on chondrocyte response to parathyroid hormone (PTH) by examining the effect of PTH(1-34) on alkaline-phosphatase-specific activity (ALPase) of chondrocyte cultures at two distinct stages of maturation, and to determine the signaling pathways used by the cells to mediate this effect. Confluent, fourth passage rat costochondral resting zone (RC) and growth zone (GC) chondrocytes were used. ALPase was measured in the cell layer, as well as in matrix vesicles (MV) and plasma membranes (PM), after the addition of 10(-7) 10(-11) mol/L bovine PTH(1-34), the active peptide, or bovine PTH(3-34), the inactive peptide, to the cultures. PTH(1-34) increased ALPase in the GC cultures at two separate times: between 5 and 180 min, with maximal stimulation at 10 min, and 36 to 48 h. In contrast, PTH(3-34) had no effect. At 10 min and 48 h, PTH(1-34) produced a dose-dependent increase in ALPase of both MV and PM isolated from GC cultures. Addition of forskolin and IBMX to increase cAMP increased ALPase in GC cultures to a level similar to that seen after addition of PTH(1-34). In contrast, the addition of PTH(1-34) to RC cells only increased ALPase between 5 and 60 min, with peak activity at 10 min. As with GC, PTH increased ALPase in both MV and PM. Moreover, the addition of PTH(3-34) or forskolin and IBMX had no effect on ALPase in RC. PTH(1-34) had no effect on GC protein kinase C (PKC) activity; however, the addition of PTH(1-34) to RC caused a dose-dependent increase in PKC activity. H8, an inhibitor of PKA, had no effect on PTH-stimulated ALPase in RC cells, but inhibited the PTH-dependent response in GC cells. In contrast, chelerythrine, an inhibitor of PKC activity, inhibited PTH-stimulated ALPase in RC cells, but had no effect on PTH-stimulated ALPase in GC cells. This study shows that the effect of PTH(1-34) on RC and GC cells is maturation dependent in terms of time course and mechanism. Whereas both cell types exhibit a rapid response to PTH, only GC cells show a long-term response. In GC, the effects of PTH are associated with changes in cAMP and may also involve at least one other pathway, whereas, in RC, the PTH effects appear to be associated with changes in PKC.

Expression of platelet-derived growth factor (PDGF)-A, PDGF-B and the PDGF-alpha receptor, but not the PDGF-beta receptor, in human malignant melanoma in vivo

There has been considerable interest in the potential role of growth factors in the initiation and development of cutaneous malignant melanoma (CMM). Platelet-derived growth factor (PDGF) has been shown to be secreted by melanoma cell lines and by metastatic melanoma in vivo. PDGF also has been reported to stimulate the development of tumour stroma and new blood vessels. We studied the expression of PDGF and its receptors by both immunohistochemistry (IHC) and in situ hybridization (ISH) in primary and metastatic melanoma and in normal skin specimens. Cryostat sections were incubated with 35S-labelled riboprobes and antibodies for PDGF-AA, PDGF-alpha receptor, PDGF-BB and PDGF-beta receptor. Both primary and metastatic melanoma exhibited significant expression of PDGF-AA, PDGF-BB and PDGF-alpha receptor by both IHC and ISH, compared with only background expression in normal skin. We did not observe expression of PDGF-beta receptor in melanoma. Our results suggest that PDGF may function as an autocrine growth factor, as well as an angiogenesis factor, in CMM tumour development. This expression of the PDGF-alpha receptor rather than the beta receptor may be unique among solid tumours.

Synthesis of inositol 2-phosphate-quercetin conjugates

The antiproliferative flavonoid, quercetin, is limited in its pharmacological utility by its low water solubility. In this paper, we describe the synthesis of two quercetin analogues prepared by linking the hydroxyl group at the 3- or 5-position of the flavonoid to the 1-hydroxyl group of myo-inositol-2-phosphate via a succinate diester linkage. The resulting conjugates were found to have dramatically enhanced water solubility relative to quercetin; the 5-linked quercetin analogue 2 had a water solubility of > 300 mg/mL at 20 degrees C. Comparison of the in vitro cytotoxicity and antiproliferative activity of conjugate 2 with those of quercetin toward cultured human colon adenocarcinoma (SW480) and human glioblastoma (U87MG) cells indicated that this modification of quercetin does not significantly diminish its activity in these assays.

Safety of recombinant deoxyribonucleic acid-derived growth hormone: The National Cooperative Growth Study experience

The National Cooperative Growth Study has monitored the safety of recombinant human GH (rhGH) since 1985. Data have been collected from more than 19,000 children representing over 47,000 patient-years of rhGH treatment. Children receiving GH for renal disease were more likely to develop problems such as intracranial hypertension than those with GH deficiency (P < 0.01). Children with idiopathic short stature were less likely to develop slipped capital femoral epiphysis than those with GH deficiency or Turner's syndrome (P < 0.01). There was no evidence of an increased recurrence of leukemia or central nervous system tumors. There were 3 new cases of leukemia in children without known risk factors for developing leukemia and 5 cases in children with known risk factors. Growth deceleration associated with high affinity, high capacity antibodies to GH was found in only 2 of 5039 subjects tested (0.04%). Major adverse events in association with rhGH treatment have been rare, and preexisting medical conditions such as renal insufficiency may affect their frequency.

Human papilloma virus and p53 in head and neck cancer: clinical correlates and survival

Recent studies have shown that p53 mutations are frequently found in cancer of the head and neck, whereas others have indicated that human papilloma virus (HPV) infection may be involved. Thus far, no studies have examined both p53 and HPV in the same patient population and correlated the results with clinical characteristics and outcome. The purpose of this study was to examine any interrelationship between p53 and HPV in patients with squamous cell carcinoma (SCC) of the head and neck. We also planned to correlate the experimental findings with clinical characteristics, known risk factors, and treatment outcome to determine whether any prognostic factors could be detected. Archival material from 66 patients with SCC of the head and neck were selected for study based on the availability of tissue from the primary tumors prior to treatment. A data base was constructed containing all clinical parameters at the time of diagnosis and risk factors. Genomic DNA was isolated and amplified using PCR, followed by SSCP analysis and direct genomic sequencing of all variants to detect p53 mutations. Two independent methods were used for HPV detection: (a) PCR amplification using primers homologous to the E6 region of HPV 16, 18, and 33, followed by RFLP analysis; and (b) PCR amplification with HPV L1 consensus primers, followed by triple restriction enzyme digestion. The results were entered into the data base for statistical analysis. Twenty-four percent of patients were found to have p53 mutations, and 18% were positive for HPV infection. Only one patient was positive for both. Tonsilar cancer was strongly correlated with HPV (P = 0.0001) and inversely correlated with p53 (P = 0.03). The only clinical parameter associated with p53 mutation was a trend toward a heavier smoking history. A subset analysis of the patients with tonsilar cancer revealed inverse correlations with smoking (P = 0. 015) and alcohol use (P = 0.05). Also, white patients with SCC of the tonsil were more likely to be HPV positive (P = 0.015). No significant relationships with outcome were detected with either p53 or HPV in the entire population. A subset analysis of patients with stage IV disease revealed that HPV infection was correlated with overall survival. This is the largest study to date to examine both p53 and HPV in patients with SCC of the head and neck. Our results suggest that HPV may be involved in the development of these cancers in patients without traditional risk factors and that HPV-related cancers are more prevalent in the white race.

p53 mutation does not correlate with radiosensitivity in 24 head and neck cancer cell lines

The molecular basis of tumor response to therapeutic radiation is poorly understood. Recent evidence suggests the p53 tumor suppressor gene may be involved in production of the G1 arrest seen following DNA damage by X-irradiation. It has further been proposed that tumor cells lacking the p53 checkpoint function are likely to be more sensitive to cell killing by X-irradiation because these cells enter S phase despite unrepaired DNA damage. We tested the hypothesis that tumor cells with p53 mutations are more radiosensitive by correlating the in vitro surviving fraction at 2 Gy with the mutational status of 24 head and neck squamous cell cancer cell lines. p53 mutations were present in 15 of 24 (63%) of tumors; all were homozygous changes occurring within exons 5-9. The surviving fraction at 2 Gy for the group with mutations was 0.568 compared to 0.507 for tumors without mutations (P = 0.28, Mann-Whitney test). Furthermore, no association between radiosensitivity and mutational type, codon location, or predicted amino acid alteration was noted. Our data do not support the hypothesis that p53 gene alteration predisposes tumor cells to increased cell killing via radiation.

Referring patients for domiciliary care

This article attempts to identify some of the reasons why patients who meet the referral criteria of domiciliary palliative nursing care services are not referred. A study was conducted among district nurses and GPs which highlighted that a 'conspiracy of silence' still existed between patients, professionals and families. A desire to manage patients themselves and a misunderstanding of the work of Macmillan nurses were also reported. Some recommendations for change are made.

Outbreak of ceftazidime resistance due to a novel extended-spectrum beta-lactamase in isolates from cancer patients

Ceftazidime is widely used in the therapy of infectious complications in neutropenic patients. We studied an outbreak of ceftazidime-resistant gram-negative bacillary infections in pediatric cancer patients receiving empirical ceftazidime therapy for neutropenic fever. Fourteen isolates (12 Klebsiella pneumoniae and 2 Escherichia coli) from 13 patients were studied. Specimens were obtained from multiple clinical sites including blood, urine, throat, and lung. The organisms were resistant to ceftazidime, aztreonam, and penicillins but remained susceptible to cephamycins and imipenem. All resistant isolates produced a novel beta-lactamase (TEM-26) with a pI of approximately 5.58, which was transferred by transformation to E. coli on a 7.9-kb nonconjugative plasmid which cotransferred resistance to trimethoprim-sulfamethoxazole. This enzyme readily hydrolyzed ceftazidime, aztreonam, and penicillins in a spectrophotometric assay. DNA sequencing data suggest that TEM-26 is derived from TEM-1.

Occurrence of p53 gene deletions and human papilloma virus infection in human head and neck cancer

Little is known regarding the molecular genetic events in head and neck carcinoma. Epidemiological evidence suggests that both alcohol and tobacco use are related to the development of these neoplasms, and viral infections have also been postulated to play a role in some tumors. Loss of p53 tumor suppressor gene function has been found in many malignancies and can occur through either gene mutation or by interaction with the E6 protein of oncogenic human papilloma viruses (HPV). Because the mucosal surfaces of the head and neck are exposed to mutagens and HPVs, we studied DNA derived from 30 stage I-IV squamous cell carcinomas of the head and neck (9 primary tumors and 21 early passage cell lines) for p53 gene mutations as well as for the presence of oncogenic HPV DNA. Exons 2 through 11 of the p53 gene were examined using single strand conformation polymorphism analysis followed by direct genomic sequencing of all variants. HPV detection was done using polymerase chain reaction amplification with HPV E6 region type specific primers as well as L1 region degenerate ("consensus") primers; HPV type was determined by restriction fragment length polymorphism analysis of the amplified fragment as well as by Southern blotting of genomic DNA. Sixteen of 30 tumors (53%) had p53 mutations and oncogenic HPV DNA was detected in 3 of 30 (10%) tumors, none of which had p53 mutations. The p53 mutational spectrum observed was characterized by equal frequencies of transversions (6 of 16), transitions (5 of 16), and deletions (5 of 16). This distribution of mutations differs from the spectrum of p53 mutation reported in esophageal (P = 0.05) and lung (P = 0.02) cancers, two other tobacco associated neoplasms. A previously undescribed clustering of 3 mutations at codon 205 was also observed. A trend toward a shorter time to tumor recurrence after treatment was noted for those patients with tumors exhibiting p53 gene mutations, and no relationship between p53 mutations and tumor stage or node status was noted. Alteration in p53 gene function appears common in head and neck cancer, and the mutational spectrum observed may reflect the role of different mutagens or mutagenic processes than those responsible for the p53 mutations in lung and esophageal neoplasms.

Amplification and expression of heterologous oncostatin M in Chinese hamster ovary cells

A stable Chinese hamster ovary (CHO) cell line producing high levels of human oncostatin M (OM) was generated by transfecting a heterologous gene coding for the protein. This novel construct was comprised of the gene for the transforming growth factor-beta 1 (TGF-beta 1) signal peptide fused to the gene for mature human OM. Amplification with methotrexate produced milligram quantities of this recombinant OM, which was processed correctly, glycosylated, and found to have biological functions similar to those of natural OM.

Intravascular membrane oxygenation and carbon dioxide removal--a new application for permissive hypercapnia?

Pressure limited ventilation or "lung rest" may prevent further exacerbation of acute lung injury from high airway pressures. A therapeutic goal of an intracorporeal oxygenation and carbon dioxide removal device (IVOX) is reduction of airway pressures. We noted increased IVOX CO2 removal as mixed venous CO2 increased in experimental animals. However, we recognize the limited clinical utility of removing approximately 30% of venous CO2. Therefore, intentional hypoventilation to limit airway pressures (mild permissive hypercapnia) was used in 5 patients with respiratory failure, and again we noted improved CO2 removal with increasing mixed venous CO2 concentrations. Preliminary calculations demonstrate that a CO2 gradient of approximately 70 mm Hg is needed to remove 100 ml CO2/min. The use of more aggressive permissive hypercapnia protocols with IVOX may permit further reduction in airway pressure without problems of severe respiratory acidosis.

Synthesis and muscarinic activities of quinuclidin-3-yltriazole and -tetrazole derivatives

The synthesis of 15 methyl or unsubstituted 1,2,3-triazoles, 1,2,4-triazoles, and tetrazoles additionally substituted with a 1-azabicyclo[2.2.2]octan-3-yl group is described. The potency and efficacy of these compounds as muscarinic ligands were determined in radioligand binding assays using [3H]oxotremorine and [3H]quinuclidinyl benzilate. Potency and efficacy were found in compounds in which the azole moiety was attached to the azabicyclic ring either through a carbon atom or a nitrogen atom. Electrostatic potential maps of both the C-linked and the novel N-linked series of compounds were calculated. A relationship between position and depth of the electrostatic minima relative to the azabicyclic ring and the potency and efficacy of the compounds was determined.

Retinal pigment epithelial cells secrete interleukin-6 in response to interleukin-1

Interleukin-6 (IL-6) is a peptide whose properties include the ability to activate T-lymphocytes, stimulate the secretion of immunoglobulin, induce neuronal differentiation, and trigger the release of acute phase proteins. We have detected IL-6-like activity in conditioned medium from cultured human retinal pigment epithelial (RPE) cells with a bioassay based on the ability of IL-6 to induce the proliferation of murine B-9 plasmacytoma cells. Biologic activity increased approximately 90-fold when the cells were cultured in the presence of IL-1 alpha (30 units/ml). Western blot analysis confirmed that conditioned medium from IL-1 alpha-stimulated RPE cells contained peptides with molecular weights ranging between 19,000 and 30,000 and reactive with antibody to IL-6. Finally, Northern blot analysis indicated that cells cultured in the presence of interleukin-1 contained a 1.2 kilobase transcript that hybridized to a cDNA probe specific for IL-6 messenger RNA. IL-6 peptide on Western blots and mRNA on Northern blots were undetectable unless cells were cultured in the presence of IL-1 alpha. Although IL-6 is synthesized by a variety of cell types, this report is the first to detect its synthesis by an eye-specific cell type. Furthermore, these observations indicate that retinal pigment epithelial cells respond to IL-1, a cytokine that previously has been implicated in ocular inflammation.

Detection of human Pneumocystis carinii by the polymerase chain reaction

Oligonucleotide primers were prepared from a clone (B12) which has been shown to be a repetitive sequence in the rat P. carinii genome. Polymerase chain reaction was employed to amplify both rat and human P. carinii DNA. The detection limit of the assay was approximately 600 ng of total nucleic acid. Amplification products from both the rat and human isolates (ca. 780 bp) were characterized by denaturing gradient gel electrophoresis after digestion with Sau3A. No amplification products were obtained when DNA from the following potential pulmonary pathogens were used in identical reactions: Aspergillus fumigatus, Cryptococcus neoformans, Candida albicans, Mycobacterium avium-intracellulare and cytomegalovirus. In a blind study using the B12 primers, P. carinii DNA was successfully amplified in clinical samples which were positive by direct immunofluorescence assay (IFA) as well as in some specimens not identified by direct IFA.

Structural analysis of the gene for human acidic fibroblast growth factor

Genomic clones derived from the gene for human acidic fibroblast growth factor (aFGF) have been isolated. Nucleotide sequence analysis of these clones revealed that the coding region of the human aFGF gene is interrupted by two introns, located at precisely homologous locations to introns in four other members of the FGF gene family, strongly indicating a common evolutionary origin for these genes. Northern blot analyses of the multiple aFGF transcripts found in serum-stimulated human foreskin fibroblasts indicated that the aFGF gene also contains a third intron, lying in the 5' untranslated region.

Antithyroid antibodies in Hispanic patients with type I diabetes mellitus. Prevalence and significance

Antithyroglobulin antibodies (ATA) and antithyroid microsomal antibodies (AMA) were sought and thyroid function was determined in 90 Hispanic patients with type I diabetes mellitus followed up for up to seven years. We detected ATA in 7.5% of our patients and AMA in 34.8%. All serum samples positive for ATA also contained AMA. There was no sex difference in the prevalence of thyroid autoimmunity. A small, firm goiter was present in eight patients, one of whom developed Graves' disease. Our results suggest that a relatively high prevalence of AMA and no sex difference in thyroid autoimmunity may be unique features of Hispanic children and adolescents with type I diabetes mellitus. Such patients should be clinically evaluated for thyroid dysfunction and should be screened annually for the presence of AMA. When antibodies are present, laboratory evaluation of thyroid function should be performed frequently.

Comparison of the direct agglutination and indirect hemagglutination tests in the determination of blood serum titers to Escherichia coli organisms

A comparison of the direct agglutination test and the indirect hemagglutination test for the detection of blood serum antibodies to Escherichia coli organisms indicated that these serological tests were comparable. In some instances the indirect hemagglutination test provided higher endpoint readings. Preparation of the antigens for the indirect hemagglutination test was more time consuming than for the direct agglutination test. Crude extract and purified polysaccharides were comparable as red blood cell sensitizing agents.