Outcomes in 2748 patients referred to a colorectal two-week rule clinic.

OBJECTIVE: To assess the 3-year outcomes of a nurse-led, one-stop, 2-week rule (TWR) clinic for suspected colorectal cancer (CRC) in a large teaching hospital. METHOD: Data were collected prospectively from January 2002 to December 2004. In total, 2748 patients were seen over the 3-year period. The ratio of male:female subjects was 1190:1558 (43%:57%). Median age at presentation was 66 years (range 17-96). RESULTS: A total of 1363 (49.6%) nonconforming referrals were made; 1300 patients (47.3%) underwent flexible sigmoidoscopy during their initial assessment in clinic; 1439 patients (52.4%) underwent a barium enema during the course of their investigation; 2503 patients (91.1%) were seen within 14 working days. The median overall wait for the initial clinic appointment was 10 days. The annual number of patients seen was similar over the 3-year period. A total of 174 cancers (6.3%) were identified which accounted for 36.4% of all CRCs diagnosed during the study period. Nineteen cancers presented in the nonconforming group (1.6% of all non-conforming patients). Rectal tumours accounted for 59.8% (n = 104) of all cancers diagnosed while right-sided tumours accounted for only 10.9% (n = 19). Advanced tumours accounted for 73.0% (n = 127) of the total; 133 (76.4%) cancer patients underwent some form of surgical intervention. CONCLUSION: A specialist nurse-led, one-stop TWR clinic for suspected colorectal cancer is sustainable and can be run successfully with over 90% of referrals seen within the targeted time period. The proportion of non-conforming referrals was high and a large number of advanced and unstaged tumours was observed. Low numbers of proximal tumours were detected.

The structure of phosphorylated GSK-3beta complexed with a peptide, FRATtide, that inhibits beta-catenin phosphorylation.

BACKGROUND: Glycogen synthase kinase-3 (GSK-3) sequentially phosphorylates four serine residues on glycogen synthase (GS), in the sequence SxxxSxxxSxxx-SxxxS(p), by recognizing and phosphorylating the first serine in the sequence motif SxxxS(P) (where S(p) represents a phosphoserine). FRATtide (a peptide derived from a GSK-3 binding protein) binds to GSK-3 and blocks GSK-3 from interacting with Axin. This inhibits the Axin-dependent phosphorylation of beta-catenin by GSK-3. RESULTS: Structures of uncomplexed Tyr216 phosphorylated GSK-3beta and of its complex with a peptide and a sulfate ion both show the activation loop adopting a conformation similar to that in the phosphorylated and active forms of the related kinases CDK2 and ERK2. The sulfate ion, adjacent to Val214 on the activation loop, represents the binding site for the phosphoserine residue on 'primed' substrates. The peptide FRATtide forms a helix-turn-helix motif in binding to the C-terminal lobe of the kinase domain; the FRATtide binding site is close to, but does not obstruct, the substrate binding channel of GSK-3. FRATtide (and FRAT1) does not inhibit the activity of GSK-3 toward GS. CONCLUSIONS: The Axin binding site on GSK-3 presumably overlaps with that for FRATtide; its proximity to the active site explains how Axin may act as a scaffold protein promoting beta-catenin phosphorylation. Tyrosine 216 phosphorylation can induce an active conformation in the activation loop. Pre-phosphorylated substrate peptides can be modeled into the active site of the enzyme, with the P1 residue occupying a pocket partially formed by phosphotyrosine 216 and the P4 phosphoserine occupying the 'primed' binding site.

A method for identification of inhibitors of the phosphorylation reactions of bacterial response regulator proteins using (31)P nuclear magnetic resonance spectroscopy.

Bacterial response regulators are attractive targets for antibacterial drug development, yet random screening against these targets has failed as yet to identify chemicals that constitute viable leads. Alternative methods to provide leads for drug development based on identification and optimization of low affinity ligands from NMR screens have been described. However, leads from these processes still require verification in a bioassay, which is often problematic if compounds have unfavorable optical and solubility properties. A simple method, based on using NMR to observe the activity of the target, is described. It has the advantages of being able to characterize both low affinity leads and a wider selection of compounds in a structure activity relationships series, without the problems affecting a fluorescence assay. In this example we use (31)P to monitor the turnover of a bacterial response regulator, but the generic approach could be applied to other nuclei and thus a range of biological systems.

The aetiology and epidemiology of faecal incontinence.

Faecal incontinence is experienced by at least 2% of the population and 7% of those over 65 years of age. The true incidence is probably much higher because of the stigmata of the affliction leading to underreporting. The common causes of faecal incontinence are discussed.

The surgical management of faecal incontinence.

The surgical management of faecal incontinence is complex and technically demanding. Surgery should only be offered once the aetiology has been correctly identified and the patient has been counselled regarding outcomes of success. This may only approach 80%, with long-term results declining with time.

Recent developments in the treatment of faecal incontinence.

Many patients with faecal incontinence can be cured using a simple anal sphincter repair. Some patients are unsuitable for this either because the sphincter is absent, too extensively damaged or anal sphincter repair has failed. In these patients novel treatments have been introduced to augment, replace and stimulate the anal sphincter.

Improving outcomes in colonic cancer.

Many of the symptoms of colon cancer do not start until the tumour has spread outside the bowel, and treatment at this stage has reduced chances of cure. Early detection and the optimum combination of surgery and adjuvant treatment can make a significant impact on outcome.

Selective small molecule inhibitors of glycogen synthase kinase-3 modulate glycogen metabolism and gene transcription.

BACKGROUND: Glycogen synthase kinase-3 (GSK-3) is a serine/threonine protein kinase, the activity of which is inhibited by a variety of extracellular stimuli including insulin, growth factors, cell specification factors and cell adhesion. Consequently, inhibition of GSK-3 activity has been proposed to play a role in the regulation of numerous signalling pathways that elicit pleiotropic cellular responses. This report describes the identification and characterisation of potent and selective small molecule inhibitors of GSK-3. RESULTS: SB-216763 and SB-415286 are structurally distinct maleimides that inhibit GSK-3alpha in vitro, with K(i)s of 9 nM and 31 nM respectively, in an ATP competitive manner. These compounds inhibited GSK-3beta with similar potency. However, neither compound significantly inhibited any member of a panel of 24 other protein kinases. Furthermore, treatment of cells with either compound stimulated responses characteristic of extracellular stimuli that are known to inhibit GSK-3 activity. Thus, SB-216763 and SB-415286 stimulated glycogen synthesis in human liver cells and induced expression of a beta-catenin-LEF/TCF regulated reporter gene in HEK293 cells. In both cases, compound treatment was demonstrated to inhibit cellular GSK-3 activity as assessed by activation of glycogen synthase, which is a direct target of this kinase. CONCLUSIONS: SB-216763 and SB-415286 are novel, potent and selective cell permeable inhibitors of GSK-3. Therefore, these compounds represent valuable pharmacological tools with which the role of GSK-3 in cellular signalling can be further elucidated. Furthermore, development of similar compounds may be of use therapeutically in disease states associated with elevated GSK-3 activity such as non-insulin dependent diabetes mellitus and neurodegenerative disease.

Transanal endoscopic microsurgery.

The anatomy of the pelvis makes it difficult to perform local excisions in the rectum when a tumour is some distance from the anal verge. Transanal endoscopic microsurgery, a minimally invasive procedure, has been developed. It provides an alternative to the transsacral or transabdominal approach, with subsequent shorter hospital stay and fewer complications.

Expression, purification, and functional analysis of the human serine protease HtrA2.

HumHtrA2 or Omi is a recently described member of a novel family of mammalian serine proteases homologous to the Escherichia coli htrA gene product. Although the physiological function of members of this new family is unclear, the current understanding is that as well as being involved with the degradation aberrantly folded proteins during conditions of cellular stress, they may possess a chaperone-like role under normal conditions. In this report we describe the overexpression of humHtrA2 in two heterologous systems comparing the merits of each. We found that molecular analysis of processing events in Sf9 cells allowed us to revisit E. coli expression systems which were initially unsuccessful. Using E. coli we were able to produce milligram amounts of >90% pure recombinant enzyme as determined by SDS-PAGE gels. By means of fluorescently labeled substrates alpha- and beta-casein and zymography, the proteolytic activity of recombinant HumHtrA2 was also demonstrated.

Differential expression of Myc1 and Myc2 isoforms in cells transformed by eIF4E: evidence for internal ribosome repositioning in the human c-myc 5'UTR.

eIF4E is essential for translation initiation, but its overexpression causes malignant transformation. Recent work demonstrated that eIF4E/F participates in exposing and locating alternate translation start codons during scanning. Translation initiation of several important protooncogenes and growth-regulators, such as Myc and FGF-2, can start at CUG start codon(s) upstream of the normal open reading frame (ORF). The resulting amino-terminal extension alters the properties of these proteins and their intracellular distribution. In cells overexpressing eIF4E, c-myc is overexpressed and particularly the larger, CUG-initiated form (Myc1). Recent reports suggest that synthesis of Myc2, the normally expressed AUG-initiated form, is mediated by an IRES. To determine what role eIF4E might play in c-myc expression, the c-myc 5' untranslated region (UTR) was fused in-frame to CAT reporters, and several more derivative constructs were made. In vitro translation experiments (with and without eIF4E/F); expression in CHO cells transformed with eIF4E; and deletion/mutation analysis demonstrated that Myc1 is translated by a scanning mechanism, while Myc2 is translated by Internal Ribosome Repositioning. Moreover, the existence of a true IRES in the 5'UTR was contradicted by its failure to direct translation of a circular transcript, in contrast to hsp70. The c-myc 5'UTR also failed to engage in translation in the absence of functional eIF4F, after cleavage of the eIF4G component with CVB4 protease-2A. The Internal Repositioning Element (IRPE) in c-myc 5'UTR was delimited to nucleotides (nt) 394-440 from the P1 transcription start site.

Complications of adjuvant radiotherapy for rectal cancer.

The incidence of rectal cancer in the US is 45,000 per ann um. The 5-year survival is between 40 and 70%. This has not improved over the last 50 years despite improvements in techniques, the aid of new technology (surgical stapling devices in particular) and safer anesthesia.

Effect of prednisone on response to influenza virus vaccine in asthmatic children.

OBJECTIVE: To evaluate the immunogenicity of the influenza virus vaccine in children receiving short-course (a burst) prednisone therapy for acute asthmatic exacerbations. DESIGN: Prospective cohort study. SETTING: Outpatient pediatric clinic of a military medical center. PATIENTS: Children aged 6 months to 18 years requiring the 1996 influenza virus vaccine were eligible for the study. A total of 58 children were enrolled initially. The control group included 37 asthmatic children requiring less than 900 microg/d of inhaled prednisone and their siblings. The prednisone group included 21 children vaccinated at the beginning of a course of prednisone prescribed to treat an asthma exacerbation. Thirty-one control subjects (84%) and 19 patients in the prednisone group (90%) completed the study. Dropout was due to failure to come in for the postvaccination serum sampling. INTERVENTIONS: All study patients underwent immunization with the 1996-1997 trivalent subvirion influenza virus vaccine (FluShield; Wyeth Laboratories Inc, Marietta, Pa) containing 15-microg hemagglutinin antigens each of A/Texas/36/91 (H1N1) (A/H1), A/Wuhan/359/95 (H3N2)(A/H3), and B/Beijing/184/93 (B). The prednisone cohort received a burst of oral prednisone therapy (2 mg/kg per day for 5 days). MAIN OUTCOME MEASURES: To assess the immunogenicity of the vaccine between both groups, at least a 4-fold rise in titer and end titers of at least 1:40 to each of the 3 antigens were compared. Mean changes in geometric titers to the 3 antigens were also compared. RESULTS: Proportion of patients in each group with at least a 4-fold rise in titer to each of the influenza antigens was as follows: for A/H3N3 antigen, 15 patients (79%) in the prednisone group vs 22 controls (71%) (P = .74); for A/ H1N1 antigen, 16 patients in the prednisone group (84%) vs 20 controls (64%) (P = .20); and for B antigen, 7 patients in the prednisone group (37%) vs 8 controls (26%) (P = .53). Proportion of patients in each group with an end titer of at least 1:40 to each of the antigens was as follows: for A/ H3N2 antigen, 18 patients in the prednisone group (95%) vs 28 controls (90%) (P = .69); for A/H1N1 antigen, 17 patients in the prednisone group (89%) vs 26 controls (84%) (P = .99); and for B antigen, 7 patients in the prednisone group (37%) vs 13 controls (42%) (P = .99). There were also no significant differences between groups in the mean changes in geometric titers to any of the 3 antigens. CONCLUSIONS: Prednisone bursts did not diminish the response of asthmatic children to the 1996 influenza virus vaccine, compared with controls. Children can be effectively vaccinated against influenza virus while they are receiving prednisone therapy bursts for asthmatic exacerbations.

Human immunodeficiency virus infection and genital warts as risk factors for anal intraepithelial neoplasia in homosexual men.

The incidence of anal intraepithelial neoplasia (AIN) was studied in a group of 210 homosexual and bisexual men. The presence of genital warts and human immunodeficiency virus (HIV) infection was assessed as risk factors for the development of AIN. In all, 74 (35 per cent) of the group had histological evidence of AIN. The relative risk of being positive for HIV on AIN (relative to being negative for HIV) was 1.58 (95 per cent confidence interval (c.i.) 1.01-2.48). The relative risk of anal warts on AIN (relative to absence of anal warts) was 4.70 (95 per cent c.i. 1.81-12.20). Logistic regression analysis showed no significant interactive effect between HIV and anal warts on the risk of AIN. It is concluded from the results of a Mantel-Haenzel analysis that the presence of anal warts and HIV infection are independent risk factors for the development of AIN in homosexual and bisexual men.

Interobserver variation in the reporting of the histopathological grading of anal intraepithelial neoplasia.

AIM: To assess the consistency in the histological reporting of anal intraepithelial neoplasia (AIN) among experienced histopathologists. METHOD: One hundred anal biopsy specimens were retrieved from archival material at St Mark's Hospital, London and graded by five histopathologists according to criteria outlined by Fenger (six point scale, ranging from normal to invasive carcinoma). RESULTS: There was only moderate agreement among the pathologists, with unweighted k scores ranging from 0.09 to 0.48, and weighted k scores of 0.17 to 0.60. CONCLUSIONS: There is considerable interobserver variation in the reporting of AIN. A simplified system of grading may help to abolish this.

Anal cancer--current perspectives.

Anal cancer is uncommon accounting for only 2% of anorectal cancers. The recognition of many similarities between cervical and anal cancer has stimulated research into the identification of a common aetiological agent. DNA from human papillomaviruses has consistently been found in both of these cancers and is thought to be an important factor in the development of both of these tumours. Simultaneously, epidemiological data from the west coast of America have indicated that the demography of anal cancer may be changing. Further studies in the USA and the UK have identified certain groups at high risk of developing anal cancer. These high-risk groups include 'never married' men and immunosuppressed patients both from iatrogenic immunosuppression in transplant patients and those infected with HIV. The potential increase in anal cancer cases, due to the ever increasing numbers of patients who have received transplants and the spiralling number of the population infected with HIV make it timely to review what is known of the aetiology, presentation and management of this cancer.