Topical application of acidified nitrite to the nail renders it antifungal and causes nitrosation of cysteine groups in the nail plate

BACKGROUND

Topical treatment of nail diseases is hampered by the nail plate barrier, consisting of dense cross-linked keratin fibres held together by cysteine-rich proteins and disulphide bonds, which prevents penetration of antifungal agents to the focus of fungal infection. Acidified nitrite is an effective treatment for tinea pedis. It releases nitric oxide (NO) and other NO-related species. NO can react with thiol (-SH) groups to form nitrosothiols (-SNO).

OBJECTIVES

To determine whether acidified nitrite can penetrate the nail barrier and cure onychomycosis, and to determine whether nitrosospecies can bind to the nail plate.

METHODS

Nails were treated with a mixture of citric acid and sodium nitrite in a molar ratio of 0.54 at either low dose (0.75%/0.5%) or high dose (13.5%/9%). Immunohistochemistry, ultraviolet-visible absorbance spectroscopy and serial chemical reduction of nitrosospecies followed by chemiluminescent detection of NO were used to measure nitrosospecies. Acidified nitrite-treated nails and the nitrosothiols S-nitrosopenicillamine (SNAP) and S-nitrosoglutathione (GSNO) were added to Trichophyton rubrum and T. mentagrophytes cultures in liquid Sabouraud medium and growth measured 3 days later. Thirteen patients with positive mycological cultures for Trichophyton or Fusarium species were treated with topical acidified nitrite for 16 weeks. Repeat mycological examination was performed during this treatment time.

RESULTS

S-nitrothiols were formed in the nail following a single treatment of low- or high-dose sodium nitrite and citric acid. Repeated exposure to high-dose acidified nitrite led to additional formation of N-nitrosated species. S-nitrosothiol formation caused the nail to become antifungal to T. rubrum and T. mentagrophytes. Antifungal activity was Cu(2+) sensitive. The nitrosothiols SNAP and GSNO were also found to be antifungal. Topical acidified nitrite treatment of patients with onychomycosis resulted in > 90% becoming culture negative for T. rubrum.

CONCLUSIONS

Acidified nitrite cream results in the formation of S-nitrosocysteine throughout the treated nail. Acidified nitrite treatment makes a nail antifungal. S-nitrosothiols, formed by nitrosation of nail sulphur residues, are the active component. Acidified nitrite exploits the nature of the nail barrier and utilizes it as a means of delivery of NO/nitrosothiol-mediated antifungal activity. Thus the principal obstacle to therapy in the nail becomes an effective delivery mechanism.

Glutathione supplementation to University of Wisconsin solution causes endothelial dysfunction

INTRODUCTION

Glutathione (GSH) is added to University of Wisconsin (UW) organ preservation solution to protect against oxidative stress. This study assesses the effect of GSH-supplementation on endothelial function in tissues subjected to cold ischaemia and compares its effects to a mono-ethyl ester equivalent (GSH-MEE) and S-nitrosated GSH (GSNO).

METHODS

Rat aortic rings were stored for 1 h or 48 h in cold, hypoxic UW solution with or without GSH (3 mM), GSH-MEE (3 mM) or GSNO (100 mciroM) supplementation. Aortic rings were reoxygenated in warm Krebs solution; smooth muscle function was assessed by responses to phenylephrine (PE), and endothelial function by vasodilatation to the endothelium-dependent dilator, acetylcholine (ACh). The protective effects against oxidant-induced endothelial cell death were assessed in cultured human umbilical vein endothelial cells (HUVEC).

RESULTS

Supplementation of UW with either GSH or GSH-MEE had no effect on vascular responses to PE, but smooth muscle contraction was significantly attenuated in rings incubated for 48 h with GSNO. Endothelium-dependent relaxation was significantly impaired in tissues stored under hypoxic conditions in GSH, GSH-MEE and GSNO supplemented UW solution for 1 h. However, impairment at 48 h was significantly more pronounced in GSH-treated vessels. Cultured HUVEC death was exacerbated by GSH and GSH-MEE in unstressed cells and in those stressed with a superoxide anion generator.

CONCLUSIONS

GSH supplementation of UW solution exacerbates cold-ischaemia induced endothelial dysfunction. GSNO did not share the detrimental effects of GSH and promoted NO-mediated vasodilatation.

Recombinant swine beta interferon protects swine alveolar macrophages and MARC-145 cells from infection with Porcine reproductive and respiratory syndrome virus

Swine beta interferon (swIFN-beta) produced in HEK 293 cells infected with a recombinant, replication-defective human adenovirus 5 (Ad5) encoding the swIFN-beta gene was tested for antiviral activity against Porcine reproductive and respiratory syndrome virus (PRRSV). MARC-145 cells were incubated overnight with dilutions of supernatant fluids from HEK 293 cells infected with Ad5-swIFN-beta or with an Ad5 control virus (Ad5-Blue). Treated cells were infected with PRRSV; MARC-145 cells incubated with Ad5-Blue supernatants developed cytopathic effects (CPE), whereas those incubated with swIFN-beta showed no CPE. To confirm the antiviral activity of swIFN-beta, culture fluids from Ad5-swIFN-beta-infected cells were affinity-purified on a Sepharose-anti-swIFN-beta matrix, and the resulting fractions exhibited antiviral activity upon infection with PRRSV. The antiviral effects were specific, as they were blocked by mAbs against swIFN-beta. Additional cultures of MARC-145 cells treated with swIFN-beta-containing supernatants or affinity-purified swIFN-beta were infected with PRRSV and tested by real-time RT-PCR for viral RNA in culture supernatants at various times post-inoculation. These experiments confirmed the protective effects of swIFN-beta. swIFN-beta was also tested for antiviral activity on porcine alveolar macrophages (PAMs) obtained by bronchoalveolar lavage from PRRSV-negative swine. PAMs were treated with dilutions of swIFN-beta or Ad5-Blue culture fluids, infected with PRRSV and tested for viral RNA by real-time RT-PCR. The viral load data showed a dose-dependent protection in swIFN-beta-treated PAMs, whereas no protection was evident from Ad5-Blue culture fluids. The data demonstrate that swIFN-beta protects both MARC-145 cells and PAMs from PRRSV infection.

Pre-biopsy PSA and biopsy gleason sum; evaluating the independence of two independent variables

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Background: Traditionally PSA, Gleason sum and Clinical Stage are considered independent predictors of outcome for prostate cancer. The purpose of this study is to investigate a codependence between prostate specific antigen (PSA) and Gleason sum and whether this relationship has evolved during the PSA era. Methods: The Columbia Urologic Oncology Database was reviewed and 2,522 patients were identified who underwent radical prostatectomy from 1988 to 2005; a retrospective cohort of 1,786 patients with complete data was included. Patients were stratified by Gleason sum into groups with Gleason sum <7, =7 and >7. PSA was correlated to Gleason sum to examine a possible relationship between the two variables. Two-sample t-tests with 95% confidence intervals were utilized to determine differences between groups and were confirmed by ANOVA techniques. A Cox regression model using an interaction term between PSA and Gleason sum was fit to determine if an interaction exists between the two variables. Patients were further stratified into two cohorts by median year of surgery (1998) and the PSA-Gleason sum relationship was evaluated over time. Results: Median patient age was 61.9 years. 1,081 patients were identified with Gleason sum <7. 540 patients had a Gleason sum =7. 165 patients had a Gleason sum >7. The mean PSA values were 6.05, 6.89 and 8.41 for <7, =7 and >7 groups respectively. Differences between the means were statistically significant and validated by the ANOVA technique (p < 0.001). A Cox regression model validated PSA, Gleason sum and clinical stage as independent predictors of outcome. The addition of an interaction term into the Cox regression model between PSA and Gleason sum demonstrated a significant interaction effect between PSA and Gleason sum (p < 0.001). The relationship remained between PSA and Gleason sum within the pre and post 1998 groups (p < 0.001). Conclusions: PSA and Gleason sum are highly interrelated variables, although they each carry additional information that significantly contributes to the prediction of biochemical failure (PSA ≥0.2 ng/ml). For an individual patient, the higher the initial PSA the higher the risk of having a high Gleason sum on biopsy. This relationship has remained constant over the PSA era.

No significant financial relationships to disclose.

Evaluation of propofol and remifentanil for intravenous sedation for reducing shoulder dislocations in the emergency department

OBJECTIVES

To assess the combination of propofol and remifentanil for sedation to reduce shoulder dislocations in an ED.

METHODS

Eleven patients with anterior glenohumeral dislocation were given propofol 0.5 mg/kg and remifentanil 0.5 microg/kg iv over 90 seconds and then further doses of 0.25 mg/kg and 0.25 microg/kg, respectively, if needed. Another practitioner attempted reduction using the Milch technique.

RESULTS

Reduction was achieved in all patients within four minutes of giving sedation (range 0.3-4; mean 1.6). Seven required one attempt at shoulder reduction, three required two attempts, and one required three attempts. Mean time to recovery of alert status was three minutes (range 1-6). The mean pain score during the reduction was 1.7 out of 10 (range 0-5). Nine patients had full recall, one had partial recall, and one had no recall at all. Eight patients were "very satisfied" with the sedation and three were "satisfied". There were no respiratory or haemodynamic complications that required treatment.

CONCLUSIONS

Propofol and remifentanil provide excellent sedation and analgesia for the reduction of anterior glenohumeral dislocation, enabling rapid recovery.

European evidence based consensus on the diagnosis and management of Crohn's disease: special situations

This third section of the European Crohn's and Colitis Organisation (ECCO) Consensus on the management of Crohn's disease concerns postoperative recurrence, fistulating disease, paediatrics, pregnancy, psychosomatics, extraintestinal manifestations, and alternative therapy. The first section on definitions and diagnosis reports on the aims and methods of the consensus, as well as sections on diagnosis, pathology, and classification of Crohn's disease. The second section on current management addresses treatment of active disease, maintenance of medically induced remission, and surgery of Crohn's disease.

Activation of p38 and p42/44 MAP kinase in neuropathic pain: Involvement of VPAC2 and NK2 receptors and mediation by spinal glia

Activation of intracellular signaling pathways involving p38 and p42/44 MAP kinases may contribute importantly to synaptic plasticity underlying spinal neuronal sensitization. Inhibitors of p38 or p42/44 pathways moderately attenuated responses of dorsal horn neurons evoked by mustard oil but not brush and alleviated the behavioral reflex sensitization seen following nerve injury. Activation of p38 and p42/44 MAP kinases in spinal cord ipsilateral to constriction injury was reduced by antagonists of NMDA, VPAC2 and NK2 (but not related) receptors, the glial inhibitor propentofylline and inhibitors of TNF-alpha. A VPAC2 receptor agonist enhanced p38 phosphorylation and caused behavioral reflex sensitization in naïve animals that could be blocked by co-administration of p38 inhibitor. Conversely, an NK2 receptor agonist activated p42/44 and caused behavioral sensitization that could be prevented by co-administration of p42/44 inhibitor. Thus, spinal p38 and p42/44 MAP kinases are activated in neuropathic pain states by mechanisms involving VPAC2, NK2, NMDA receptors and glial cytokine production.

Characterization of novel splice variants of the PAC1 receptor in human neuroblastoma cells: consequences for signaling by VIP and PACAP

Expression of VPAC and PAC1 receptor isoforms was determined in six neuroblastoma cell lines as well as in human embryonic and adult brain using reverse transcriptase PCR and quantitative PCR. PAC1 receptor splice variants missing a 21 amino acid sequence in the amino terminal domain were found to be the major receptor variants in the neuroblastoma cell lines and also were highly expressed in embryonic brain compared to adult brain. In four of the neuroblastoma cell lines, VIP and PACAP stimulated cyclic AMP production with different potencies and levels of maximal stimulation. High potency and greatest maximal stimulation of cyclic AMP for each peptide were recorded in SH-SY5Y cells, indicating the presence of high affinity VIP and PACAP receptors. Further characterization of specific VPAC and PAC1 receptor isoforms was carried out in the SH-SY5Y cell line, where along with known PAC1 receptor splice variants and the VPAC2 receptor, a number of novel PAC1 receptor splice variants were identified. The comparatively low level expression of the VPAC2 receptor along with the poor responsiveness of SH-SY5Y cells to the VPAC2 receptor-specific agonist Ro 25-1553 indicated that this receptor did not contribute significantly to the observed VIP responses. When the individual PAC1 receptor isoforms were expressed in COS 7 cells, the ability of VIP to activate cyclic AMP production was increased more than 50-fold at the majority of the PAC1 receptor variants lacking the 21 amino acid amino terminal domain sequence compared to those with the complete domain. Smaller changes were seen in the potency of PACAP-38. Similar trends were seen with inositol phosphate responses, where in each case agonist potencies were lower than for cyclic AMP production. The results of this study show that the combination of different amino terminal and intracellular loop 3 splicing variants in the PAC1 receptor dictates the ability of agonists, particularly VIP, to activate signaling pathways. VIP has considerably greater potency at most PAC1 receptors with the short amino terminal domain, and these therefore may mediate physiological effects of both VIP and PACAP. Furthermore, there may be a phenotypic switch in the expression of different PAC1 receptor amino terminal splice variants between embryonic and mature nervous system, indicating that regulation of this event may have an important role in VIP/PACAP function, particularly in the developing nervous system.

The effects of guided tissue regeneration (GTR) on modified Le Fort I osteotomy healing in rabbits

Osteogenesis following surgery depends on the osteoblasts at the wound site. Fibrous nonunions may be the result of differential and rapid migration of fibroblasts compared to osteoblasts into the wound. The present study was designed to test this hypothesis through the use of guided tissue regeneration (GTR) in a rabbit model. Bilateral, Le Fort I osteotomies (n=20) were produced in the maxillae of 10 New Zealand White rabbits. The segments were advanced 6mm and rigidly fixed using microplates and screws. One side was covered with a resorbable collagen membrane or left uncovered. Rabbits were followed for four weeks with radiographs and the maxillae were harvested for histology. Cephalometry revealed that membrane-covered defects had significantly (P<0.01) reduced defect area (by approximately 70%) compared to uncovered defects. Histologically, membrane-covered defects showed more organized osteogenesis and less fibrous tissue than uncovered defects. Histomorphometry revealed that membrane covered defects had significantly (P<0.05) reduced defect areas (by approximately 20%) compared to uncovered defects. While findings suggest that GTR can facilitate osseous wound healing in Le Fort I osteotomies, results also caution against relying exclusively on two-dimensional radiography to assess bony wound healing in lieu of three-dimensional imaging and evaluations.

Measurement of the D(s)+ lifetime

A high statistics measurement of the D(s)+ lifetime from the Fermilab fixed-target FOCUS photoproduction experiment is presented. We describe the analysis of the two decay modes, D(s)+ --> phi(1020)pi+ and D(s)+ -->K*(892)0K+, used for the measurement. The measured lifetime is 507.4 +/- 5.5(stat) +/- 5.1(syst) fs using 8961 +/- 105 D(s)+ --> phi(1020)pi+ and 4680 +/- 90 D(s)+ --> K*(892)0K+ decays. This is a significant improvement over the present world average.

Measurement of limestone biodeterioration using the Ca2+ binding fluorochrome Rhod-5N

Limestone and marble have been used extensively in the construction of modern and historic buildings. Microbial colonization and growth on these stone structures is common. Microbial deterioration of stone has been assessed by measuring Ca2+ released from the stone, using ion selective electrodes and titration with EDTA. In this study, the calcium binding fluorochrome Rhod-5N was used to measure Ca2+ released from limestone by endolithic bacteria as an indicator of biodeterioration. In a 17 d flask experiment, Ca2+ released by endolithic bacteria was twice that of uninoculated controls. Rhod-5N is a rapid and accurate method for measuring microbial biodeterioration of stone.

The neural basis of maternal responsiveness to infants: an fMRI study

Using fMRI, we examined the neural correlates of maternal responsiveness. Ten healthy mothers viewed alternating blocks of video: (i) 40 s of their own infant; (ii) 20 s of a neutral video; (iii) 40 s of an unknown infant and (iv) 20 s of neutral video, repeated 4 times. Predominant BOLD signal change to the contrasts of infants minus neutral stimulus occurred in bilateral visual processing regions (BA 19,21,37,38); to own infant minus unknown infant in right anterior temporal pole (BA 38), left amygdala and visual cortex (BA 19), and to the unknown infant minus own infant contrast in bilateral orbitofrontal cortex (BA 10,47) and medial prefrontal cortex (BA 8) [corrected] These findings suggest that amygdala and temporal pole may be key sites in mediating a mother's response to her infant and reaffirms their importance in face emotion processing and social behaviour.

A patient with Rothmund–Thomson syndrome and tongue cancer — experience of radiation toxicity

We describe a male patient with Rothmund-Thomson syndrome (RTS) given postoperative radiotherapy for squamous carcinoma of the tongue. This was well tolerated. This is only the second reported case of oral cancer and radiotherapy in RTS.

Temperature at birth, coronary heart disease, and insulin resistance: cross sectional analyses of the British women's heart and health study

OBJECTIVE

To assess the association of mean outdoor temperature around the time of birth with insulin resistance and coronary heart disease in later life.

DESIGN

Cross sectional study.

SETTING

23 British towns.

PARTICIPANTS

4286 women aged 60-79 years.

MAIN OUTCOME MEASURES

Coronary heart disease and insulin resistance.

RESULTS

Coronary heart disease prevalence was greatest among women born during the coldest months: the age adjusted odds ratio comparing women born in the coldest quarter of monthly outdoor birth temperatures with the remaining three quarters was 1.24 (95% confidence interval (CI) 1.03 to 1.50). Cold outdoor temperature at birth was also associated with increased insulin resistance, increased triglyceride concentrations, and poorer lung function. The link between cold outdoor temperature at birth and coronary heart disease was only partly explained by known coronary disease risk factors: fully adjusted (for all measured potential explanatory and confounding factors) odds ratio 1.19 (95% CI 0.95 to 1.48). The association between cold temperature at birth and coronary heart disease was most pronounced among those whose fathers were either unemployed or in manual social classes when the participants were children, and was non-existent in those from non-manual social classes in childhood.

CONCLUSIONS

Cold outdoor temperature at birth is associated with increased coronary heart disease, insulin resistance, dyslipidaemia, and poor lung function. Further research is needed to determine whether this finding reflects events occurring late in the third trimester of intrauterine growth or early in the postnatal period.

The p53-dependent effects of macrophage migration inhibitory factor revealed by gene targeting

Macrophage migration inhibitory factor (MIF) is a mediator of host immunity and functions as a high, upstream activator of cells within the innate and the adaptive immunological systems. Recent studies have suggested a potentially broader role for MIF in growth regulation because of its ability to antagonize p53-mediated gene activation and apoptosis. To better understand MIF's activity in growth control, we generated and characterized a strain of MIF-knockout (MIF-KO) mice in the inbred, C57BL/6 background. Embryonic fibroblasts from MIF-KO mice exhibit p53-dependent growth alterations, increased p53 transcriptional activity, and resistance to ras-mediated transformation. Concurrent deletion of the p53 gene in vivo reversed the observed phenotype of cells deficient in MIF. In vivo studies showed that fibrosarcomas induced by the carcinogen benzo[alpha]pyrene are smaller in size and have a lower mitotic index in MIF-KO mice relative to their WT counterparts. The data provide direct genetic evidence for a functional link between MIF and the p53 tumor suppressor and indicate an important and previously unappreciated role for MIF in carcinogenesis.

Children with autistic spectrum disorders. II: parents are unable to distinguish secretin from placebo under double-blind conditions

BACKGROUND

Standardised measures of behaviour have failed to detect short term improvement in children with autism following treatment with secretin. However, it is possible that standardised measures are insensitive to dimensions of child behaviour that are nonetheless detectable by parents.

AIM

To determine the ability of parents of children with autism to guess, under double blind conditions, whether their child had received secretin or placebo.

METHODS

2x2 crossover randomised blinded study, comparing the effect of synthetic human secretin 2 U/kg to placebo (saline). Sixty two children with autism (aged 43-103 months) were randomly allocated to two groups: group 1 received placebo, followed six weeks later by secretin, and group 2 received secretin followed by placebo. At the conclusion of the study, parents were asked to guess their child's group assignment.

RESULTS

Twenty seven families guessed their child's group assignment correctly and 27 guessed incorrectly. In 48 instances, parents based their guess on perceived improvement; in six cases, parents based their guess on perceived deterioration. Six families saw no difference after either infusion, and offered no guess. One family dropped out after the first infusion, and one family was lost to follow up after the second infusion.

CONCLUSION

In a controlled setting, parents of young children with autism are unable to distinguish the short term behavioural effects of secretin from placebo.

Children with autistic spectrum disorders. I: comparison of placebo and single dose of human synthetic secretin

AIMS

To examine the effect of a single dose of human synthetic secretin (HSS) on behaviour and communication in children with autism spectrum disorder (ASD) using an objective measure of communication and social reciprocity and standardised rating scales.

METHODS

Randomised, crossover, double blind, and placebo controlled trial of a single intravenous dose of human synthetic secretin (HSS) 2 CU/kg. The 62 subjects (3-8 years) were assigned to group 1 (saline placebo/HSS) or group 2 (HSS/saline placebo). Diagnosis was confirmed by ADI-R (Autism Diagnostic Interview-Revised) algorithm. Severity of symptoms was rated using the CARS (Childhood Autism Rating Scale). Outcome measures included Communication and Symbolic Behavior Scale (CSBS), Ritvo Real-life Rating Scale, weekly Global Rating Scale (GBRS) by parents and teachers, and daily log of gastrointestinal symptoms. The communication subscale of the CSBS, specifying communication function, reciprocity, and social-affective signalling was videotaped and scored by a blinded, trained observer.

RESULTS

Sixty one children completed the study. After randomisation, there were no significant differences in gender, race, age, and parent and teacher GBRS and Ritvo Scale between the two groups. Compared with placebo, secretin treatment was not associated with significant improvement of CSBS standard scores from baseline to 2 or 4 weeks post-infusion. Five children showed clinical improvement in standard scores: two after HSS and three after placebo. There were no significant changes in gastrointestinal symptoms after HSS or saline placebo.

CONCLUSIONS

A single dose of intravenous human secretin is not effective in changing behaviour and communication in children with ASD when compared to placebo.

Coverage of work related fatalities in Australia by compensation and occupational health and safety agencies

AIMS

To determine the levels of coverage of work related traumatic deaths by official occupational health and safety (OHS) and compensation agencies in Australia, to allow better understanding and interpretation of officially available statistics.

METHODS

The analysis was part of a much larger study of all work related fatalities that occurred in Australia during the four year period 1989 to 1992 inclusive and which was based on information from coroners' files. For the current study, State, Territory, and Commonwealth OHS and compensation agencies were asked to supply unit record information for all deaths identified by the jurisdictions as being due to non-suicide traumatic causes and which were identified by them as being work related, using whatever definitions the agencies were using at the relevant time. This information was matched to cases identified during the main study.

RESULTS

The percentage of working deaths not covered by any agency was 34%. Only 35% of working deaths were covered by an OHS agency, while 57% were covered by a compensation agency. The OHS agencies had minimal coverage of work related deaths that occurred on the road (to workers (8%) or commuters (3%)), whereas the compensation system covered these deaths better than those of workers in incidents that occurred in a workplace (65% versus 53%). There was virtually no coverage of bystanders (less than 8%) by either type of agency. There was marked variation in the level of coverage depending on the industry, occupation, and employment status of the workers, and the type of injury event involved in the incident.

CONCLUSIONS

When using data from official sources, the significant limitations in coverage identified in this paper need to be taken into account. Future surveillance, arising from a computerised National Coroners Information System, should result in improved coverage of work related traumatic deaths in Australia.

Rabbit calvarial wound healing by means of seeded Caprotite scaffolds

Autologous bone is the most successful bone-grafting material; however, limited supply and donor site morbidity are problematic. Synthetic bone substitutes are effective, but healing is slow and unpredictable. Osseous wound healing may be enhanced if bone substitutes are combined with autologous bone marrow cells. To test this hypothesis, we created 40 calvarial defects in 20 12-week-old New Zealand White rabbits, divided into four groups: (1) unrepaired controls, (2) autologous bone grafts, (3) unseeded Caprotite (a polymer-ceramic composite) grafts, and (4) Caprotite grafts seeded with autologous bone marrow stromal cells. CT scans were obtained at 0, 6, and 12 weeks post-operatively, and defects were harvested for histology. Defects repaired with autologous bone had significantly (p < 0.05) more bone than the other three groups, although seeded Caprotite defects showed different wound-healing sequelae. Results suggest that seeded Caprotite scaffolds did not significantly enhance osseous defect healing compared with controls.

Expression of pituitary tumour transforming gene (PTTG) and fibroblast growth factor-2 (FGF-2) in human pituitary adenomas: relationships to clinical tumour behaviour

OBJECTIVE

Pituitary tumour transforming gene (PTTG) encodes a multifunctional protein that is implicated in initiating and perpetuating pituitary adenoma growth. PTTG appears to have key regulatory functions in determining control of many fundamental cellular events including mitosis, cell transformation, DNA repair and gene regulation. Several of these events are mediated through interactions with PTTG binding factor (PBF) and fibroblast growth factor-2 (FGF-2). Given this background, we have determined the expression of PTTG, PBF, FGF-2 and its receptor FGF-R-1 in a large cohort of pituitary adenomas and have sought associations between levels of gene expression and clinical markers of tumour behaviour.

PATIENTS AND METHODS

We used real-time reverse transcriptase-polymerase chain reaction (RT-PCR) and Western blot analyses to measure PTTG, PBF, FGF-2 and FGF-R-1 expression in ex vivo pituitary tumours (N = 121). Clinical data, including accurate radiological assessment of tumour characteristics, were used to determine any associations between gene expression and tumour behaviour.

RESULTS

PTTG was increased significantly (fivefold, P = 0.005) in adenomas compared with normal pituitaries. We also demonstrated that PBF was similarly raised in adenomas (sixfold, P = 0.0001), and was significantly correlated with PTTG expression. FGF-2 and its receptor FGF-R-1 were also raised in adenomas compared with normal pituitary tissue. Moreover, significantly enhanced expression of FGF-R-1 was observed in invasive adenomas compared with other pituitary tumours.

CONCLUSIONS

Our data support a fundamental role for PTTG-mediated upregulation of FGF-2 signalling in pituitary tumorigenesis and growth, and suggest that receptor-mediated mechanisms of growth factor action may be critically important. Further prospective studies are required to determine whether measurement of FGF-R-1 mRNA will be of clinical use as a prognostic marker in patients with pituitary adenomas.