T cell-extrinsic IL-1 signaling controls long-term gammaherpesvirus infection by suppressing viral reactivation.

Gammaherpesviruses establish life-long infection in over 95% of adults and are associated with several cancers, including B cell lymphomas. Using the murine gammaherpesvirus 68 (MHV68) animal model, we previously showed a pro-viral role of Interleukin-1 (IL-1) signaling that supported viral reactivation during the establishment of chronic infection. Unexpectedly, in this study we found that the proviral effects of IL-1 signaling originally observed during the establishment of chronic gammaherpesvirus infection convert to antiviral effects during the long-term stage of infection. Specifically, IL-1 signaling promoted expansion of antiviral CD8+ T cells and control of viral reactivation in the peritoneal cavity of a long-term infected host. Using a novel mouse model of T cell-specific IL-1 signaling deficiency, we found that the antiviral effects of IL-1 signaling were T cell extrinsic. Our study highlights a dynamic nature of host factors that shape the parameters of chronic gammaherpesvirus infection.

The Antagonism between the Murine Gammaherpesvirus Protein Kinase and Global Interferon Regulatory Factor 1 Expression Shapes the Establishment of Chronic Infection.

Gammaherpesviruses infect most vertebrate species and are associated with B cell lymphomas. Manipulation of B cell differentiation is critical for natural infection and lymphomagenesis driven by gammaherpesviruses. Specifically, human Epstein-Barr virus (EBV) and murine gammaherpesvirus 68 (MHV68) drive differentiation of infected naive B cells into the germinal center to achieve exponential increase in the latent viral reservoir during the establishment of chronic infection. Infected germinal center B cells are also the target of viral lymphomagenesis, as most EBV-positive B cell lymphomas bear the signature of the germinal center response. All gammaherpesviruses encode a protein kinase, which, in the case of Kaposi's sarcoma-associated herpesvirus (KSHV) and MHV68, is sufficient and necessary, respectively, to drive B cell differentiation in vivo. In this study, we used the highly tractable MHV68 model of chronic gammaherpesvirus infection to unveil an antagonistic relationship between MHV68 protein kinase and interferon regulatory factor 1 (IRF-1). IRF-1 deficiency had minimal effect on the attenuated lytic replication of the kinase-null MHV68 in vivo. In contrast, the attenuated latent reservoir of the kinase-null MHV68 was partially to fully rescued in IRF-1-/- mice, along with complete rescue of the MHV68-driven germinal center response. Thus, the novel viral protein kinase-IRF-1 antagonism was largely limited to chronic infection dominated by viral latency and was less relevant for lytic replication during acute infection and in vitro. Given the conserved nature of the viral and host protein, the antagonism between the two, as defined in this study, may regulate gammaherpesvirus infection across species. IMPORTANCE Gammaherpesviruses are prevalent pathogens that manipulate physiological B cell differentiation to establish lifelong infection. This manipulation is also involved in gammaherpesvirus-driven B cell lymphomas, as differentiation of latently infected B cells through the germinal center response targets these for transformation. In this study, we define a novel antagonistic interaction between a conserved gammaherpesvirus protein kinase and a host antiviral and tumor suppressor transcription factor. The virus-host antagonism unveiled in this study was critically important to shape the magnitude of gammaherpesvirus-driven germinal center response. In contrast, the virus-host antagonism was far less relevant for lytic viral replication in vitro and during acute infection in vivo, highlighting the emerging concept that nonoverlapping mechanisms shape the parameters of acute and chronic gammaherpesvirus infection.

T Cell-Specific STAT1 Expression Promotes Lytic Replication and Supports the Establishment of Gammaherpesvirus Latent Reservoir in Splenic B Cells.

Gammaherpesviruses establish lifelong infections in most vertebrate species, including humans and rodents, and are associated with cancers, including B cell lymphomas. While type I and II interferon (IFN) systems of the host are critical for the control of acute and chronic gammaherpesvirus infection, the cell type-specific role(s) of IFN signaling during infection is poorly understood and is often masked by the profoundly altered viral pathogenesis in the hosts with global IFN deficiencies. STAT1 is a critical effector of all classical IFN responses along with its involvement in other cytokine signaling pathways. In this study, we defined the effect of T cell-specific STAT1 deficiency on the viral and host parameters of infection with murine gammaherpesvirus 68 (MHV68). MHV68 is a natural rodent pathogen that, similar to human gammaherpesviruses, manipulates and usurps B cell differentiation to establish a lifelong latent reservoir in B cells. Specifically, germinal center B cells host the majority of latent MHV68 reservoir in the lymphoid organs, particularly at the peak of viral latency. Unexpectedly, T cell-specific STAT1 expression, while limiting the overall expansion of the germinal center B cell population during chronic infection, rendered these B cells more effective at hosting the latent virus reservoir. Further, T cell-specific STAT1 expression in a wild type host limited circulating levels of IFNγ, with corresponding increases in lytic MHV68 replication and viral reactivation. Thus, our study unveils an unexpected proviral role of T cell-specific STAT1 expression during gammaherpesvirus infection of a natural intact host. IMPORTANCE Interferons (IFNs) represent a major antiviral host network vital to the control of multiple infections, including acute and chronic gammaherpesvirus infections. Ubiquitously expressed STAT1 plays a critical effector role in all classical IFN responses. This study utilized a mouse model of T cell-specific STAT1 deficiency to define cell type-intrinsic role of STAT1 during natural gammaherpesvirus infection. Unexpectedly, T cell-specific loss of STAT1 led to better control of acute and persistent gammaherpesvirus replication and decreased establishment of latent viral reservoir in B cells, revealing a surprisingly diverse proviral role of T cell-intrinsic STAT1.

Conserved Gammaherpesvirus Protein Kinase Counters the Antiviral Effects of Myeloid Cell-Specific STAT1 Expression To Promote the Establishment of Splenic B Cell Latency.

Gammaherpesviruses establish lifelong infections and are associated with B cell lymphomas. Murine gammaherpesvirus 68 (MHV68) infects epithelial and myeloid cells during acute infection, with subsequent passage of the virus to B cells, where physiological B cell differentiation is usurped to ensure the establishment of a chronic latent reservoir. Interferons (IFNs) represent a major antiviral defense system that engages the transcriptional factor STAT1 to attenuate diverse acute and chronic viral infections, including those of gammaherpesviruses. Correspondingly, global deficiency of type I or type II IFN signaling profoundly increases the pathogenesis of acute and chronic gammaherpesvirus infection, compromises host survival, and impedes mechanistic understanding of cell type-specific role of IFN signaling. Here, we demonstrate that myeloid-specific STAT1 expression attenuates acute and persistent MHV68 replication in the lungs and suppresses viral reactivation from peritoneal cells, without any effect on the establishment of viral latent reservoir in splenic B cells. All gammaherpesviruses encode a conserved protein kinase that antagonizes type I IFN signaling in vitro. Here, we show that myeloid-specific STAT1 deficiency rescues the attenuated splenic latent reservoir of the kinase-null MHV68 mutant. However, despite having gained access to splenic B cells, the protein kinase-null MHV68 mutant fails to drive B cell differentiation. Thus, while myeloid-intrinsic STAT1 expression must be counteracted by the gammaherpesvirus protein kinase to facilitate viral passage to splenic B cells, expression of the viral protein kinase continues to be required to promote optimal B cell differentiation and viral reactivation, highlighting the multifunctional nature of this conserved viral protein during chronic infection. IMPORTANCE IFN signaling is a major antiviral system of the host that suppresses replication of diverse viruses, including acute and chronic gammaherpesvirus infection. STAT1 is a critical member and the primary antiviral effector of IFN signaling pathways. Given the significantly compromised antiviral status of global type I or type II IFN deficiency, unabated gammaherpesvirus replication and pathogenesis hinders understanding of cell type-specific antiviral effects. In this study, a mouse model of myeloid-specific STAT1 deficiency unveiled site-specific antiviral effects of STAT1 in the lungs and peritoneal cavity, but not the spleen, of chronically infected hosts. Interestingly, expression of a conserved gammaherpesvirus protein kinase was required to counteract the antiviral effects of myeloid-specific STAT1 expression to facilitate latent infection of splenic B cells, revealing a cell type-specific virus-host antagonism during the establishment of chronic gammaherpesvirus infection.

Interferon Regulatory Factor 3 Supports the Establishment of Chronic Gammaherpesvirus Infection in a Route- and Dose-Dependent Manner.

Gammaherpesviruses are ubiquitous pathogens that establish lifelong infections and are associated with several malignancies, including B cell lymphomas. Uniquely, these viruses manipulate B cell differentiation to establish long-term latency in memory B cells. This study focuses on the interaction between gammaherpesviruses and interferon regulatory factor 3 (IRF-3), a ubiquitously expressed transcription factor with multiple direct target genes, including beta interferon (IFN-ß), a type I IFN. IRF-3 attenuates acute replication of a plethora of viruses, including gammaherpesvirus. Furthermore, IRF-3-driven IFN-ß expression is antagonized by the conserved gammaherpesvirus protein kinase during lytic virus replication in vitro In this study, we have uncovered an unexpected proviral role of IRF-3 during chronic gammaherpesvirus infection. In contrast to the antiviral activity of IRF-3 during acute infection, IRF-3 facilitated establishment of latent gammaherpesvirus infection in B cells, particularly, germinal center and activated B cells, the cell types critical for both natural infection and viral lymphomagenesis. This proviral role of IRF-3 was further modified by the route of infection and viral dose. Furthermore, using a combination of viral and host genetics, we show that IRF-3 deficiency does not rescue attenuated chronic infection of a protein kinase null gammaherpesvirus mutant, highlighting the multifunctional nature of the conserved gammaherpesvirus protein kinases in vivo In summary, this study unveils an unexpected proviral nature of the classical innate immune factor, IRF-3, during chronic virus infection.IMPORTANCE Interferon regulatory factor 3 (IRF-3) is a critical component of the innate immune response, in part due to its transactivation of beta interferon (IFN-ß) expression. Similar to that observed in all acute virus infections examined to date, IRF-3 suppresses lytic viral replication during acute gammaherpesvirus infection. Because gammaherpesviruses establish lifelong infection, this study aimed to define the antiviral activity of IRF-3 during chronic infection. Surprisingly, we found that, in contrast to acute infection, IRF-3 supported the establishment of gammaherpesvirus latency in splenic B cells, revealing an unexpected proviral nature of this classical innate immune host factor.

B Cell-Intrinsic Expression of Interferon Regulatory Factor 1 Supports Chronic Murine Gammaherpesvirus 68 Infection.

Gammaherpesviruses are ubiquitous pathogens that are associated with cancers, including B cell lymphomas. These viruses are unique in that they infect naive B cells and subsequently drive a robust polyclonal germinal center response in order to amplify the latent reservoir and to establish lifelong infection in memory B cells. The gammaherpesvirus-driven germinal center response in combination with robust infection of germinal center B cells is thought to precipitate lymphomagenesis. Importantly, host and viral factors that selectively affect the gammaherpesvirus-driven germinal center response remain poorly understood. Global deficiency of antiviral tumor-suppressive interferon regulatory factor 1 (IRF-1) selectively promotes the murine gammaherpesvirus 68 (MHV68)-driven germinal center response and expansion of the viral latent reservoir. To determine the extent to which antiviral effects of IRF-1 are B cell intrinsic, we generated mice with conditional IRF-1 deficiency. Surprisingly, B cell-specific IRF-1 deficiency attenuated the establishment of chronic infection and the germinal center response, indicating that MHV68 may, in a B cell-intrinsic manner, usurp IRF-1 to promote the germinal center response and expansion of the latent reservoir. Further, we found that B cell-specific IRF-1 deficiency led to reduced levels of active tyrosine phosphatase SHP1, which plays a B cell-intrinsic proviral function during MHV68 infection. Finally, results of this study indicate that the antiviral functions of IRF-1 unveiled in MHV68-infected mice with global IRF-1 deficiency are mediated via IRF-1 expression by non-B cell populations.IMPORTANCE Gammaherpesviruses establish lifelong infection in over 95% of all adults and are associated with B cell lymphomas. The virus's manipulation of the germinal center response and B cell differentiation to establish lifelong infection is thought to also precipitate malignant transformation, through a mechanism that remains poorly understood. The host transcription factor IRF-1, a well-established tumor suppressor, selectively attenuates MHV68-driven germinal center response, a phenotype that we originally hypothesized to occur in a B cell-intrinsic manner. In contrast, in testing, B cell-intrinsic IRF-1 expression promoted the MHV68-driven germinal center response and the establishment of chronic infection. Our report highlights the underappreciated multifaceted role of IRF-1 in MHV68 infection and pathogenesis.

Tumor suppressor Interferon Regulatory Factor 1 selectively blocks expression of endogenous retrovirus.

Endogenous retroviruses (ERVs) comprise 10% of the genome, with many of these transcriptionally silenced post early embryogenesis. Several stimuli, including exogenous virus infection and cellular transformation can reactivate ERV expression via a poorly understood mechanism. We identified Interferon Regulatory Factor 1 (IRF-1), a tumor suppressor and an antiviral host factor, as a suppressor of ERV expression. IRF-1 decreased expression of a specific mouse ERV in vitro and in vivo. IRF-3, but not IRF-7, also decreased expression of distinct ERV families, suggesting that suppression of ERVs is a relevant biological function of the IRF family. Given the emerging appreciation of the physiological relevance of ERV expression in cancer, IRF-1-mediated suppression of specific ERVs may contribute to the overall tumor suppressor activity of this host factor.

Synthesis and summary of patient-reported outcome measures to inform the development of a core outcome set in colorectal cancer surgery.

AIM: Patient-reported outcome (PRO) measures (PROMs) are standard measures in the assessment of colorectal cancer (CRC) treatment, but the range and complexity of available PROMs may be hindering the synthesis of evidence. This systematic review aimed to: (i) summarize PROMs in studies of CRC surgery and (ii) categorize PRO content to inform the future development of an agreed minimum 'core' outcome set to be measured in all trials. METHOD: All PROMs were identified from a systematic review of prospective CRC surgical studies. The type and frequency of PROMs in each study were summarized, and the number of items documented. All items were extracted and independently categorized by content by two researchers into 'health domains', and discrepancies were discussed with a patient and expert. Domain popularity and the distribution of items were summarized. RESULTS: Fifty-eight different PROMs were identified from the 104 included studies. There were 23 generic, four cancer-specific, 11 disease-specific and 16 symptom-specific questionnaires, and three ad hoc measures. The most frequently used PROM was the EORTC QLQ-C30 (50 studies), and most PROMs (n = 40, 69%) were used in only one study. Detailed examination of the 50 available measures identified 917 items, which were categorized into 51 domains. The domains comprising the most items were 'anxiety' (n = 85, 9.2%), 'fatigue' (n = 67, 7.3%) and 'physical function' (n = 63, 6.9%). No domains were included in all PROMs. CONCLUSION: There is major heterogeneity of PRO measurement and a wide variation in content assessed in the PROMs available for CRC. A core outcome set will improve PRO outcome measurement and reporting in CRC trials.

A systematic review of outcome reporting in colorectal cancer surgery.

AIM: Evaluation of surgery for colorectal cancer (CRC) is necessary to inform clinical decision-making and healthcare policy. The standards of outcome reporting after CRC surgery have not previously been considered. METHOD: Systematic literature searches identified randomized and nonrandomized prospective studies reporting clinical outcomes of CRC surgery. Outcomes were listed verbatim, categorized into broad groups (outcome domains) and examined for a definition (an appropriate textual explanation or a supporting citation). Outcome reporting was considered inconsistent if results of the outcome specified in the methods were not reported. Outcome reporting was compared between randomized and nonrandomized studies. RESULTS: Of 5644 abstracts, 194 articles (34 randomized and 160 nonrandomized studies) were included reporting 766 different clinical outcomes, categorized into seven domains. A mean of 14 ± 8 individual outcomes were reported per study. 'Anastomotic leak', 'overall survival' and 'wound infection' were the three most frequently reported outcomes in 72, 60 and 44 (37.1%, 30.9% and 22.7%) studies, respectively, and no single outcome was reported in every publication. Outcome definitions were significantly more often provided in randomized studies than in nonrandomized studies (19.0% vs 14.9%, P = 0.015). One-hundred and twenty-seven (65.5%) papers reported results of all outcomes specified in the methods (randomized studies, n = 21, 61.5%; nonrandomized studies, n = 106, 66.2%; P = 0.617). CONCLUSION: Outcome reporting in CRC surgery lacks consistency and method. Improved standards of outcome measurement are recommended to permit data synthesis and transparent cross-study comparisons.

The association between referral source and stage of disease in patients with colorectal cancer.

OBJECTIVE: The colorectal fast track (FT) referral system was set up to ensure patients with suspected cases of colorectal cancer (CRC) received prompt access to specialized services. The aim of this study was to ascertain the association between referral source and the time it took to be seen by a colorectal surgeon to establish whether referral source had any association with the stage of disease at presentation in patients with CRC. METHOD: Consecutive patients with newly diagnosed CRC presenting between October 2002 and September 2004 were identified retrospectively. Mode of presentation, symptoms, treatment and histopathology data were analysed. RESULTS: Data for 193 patients were analysed. Ninety seven patients (50%) presented via the FT system, 43 (22.5%) from nonfast track outpatient sources (NFT) and 53 (27.5%) as emergencies. NFT patients took significantly longer to be seen by a colorectal specialist than FT patients (median 69 vs 31 days; P < 0.001) and to initiation of treatment (median 57.5 vs 42.5 days; P = 0.001). Overall 152 patients (79%) presented with symptoms that met the FT criteria. A significantly lower number of NFT (P = 0.001) and emergency patients (P < 0.001) presented with FT symptoms compared with patients referred through the FT system. There was no significant difference between referral groups in patients undergoing surgery with potentially curative intent or stage of disease. CONCLUSION: Nonfast track referral leads to a significant delay in being seen by a specialist and in initiation of treatment but no association with more advanced stage of disease or a reduction in potentially curative surgery was found.

Pulmonary staging in colorectal cancer--is computerised tomography the answer?

INTRODUCTION: Pulmonary staging in colorectal cancer (CRC) has traditionally been carried out by means of plain chest radiograph (CXR), although computerised tomography (CT) imaging of the chest is increasingly being performed for this purpose. The aim of this study was to assess the value of pre-operative thoracic CT for pulmonary staging in CRC. PATIENTS AND METHODS: Data were collected prospectively on all patients referred into hospital over a 20-month study period for double contrast barium enema evaluation of symptoms suggestive of an underlying CRC. Patients with a CRC went on to have a staging intravenous, contrast-enhanced CT of the chest, abdomen and pelvis prior to an out-patient appointment with a colorectal surgeon. The CXRs of those patients in whom a radiological abnormality was seen on thoracic CT were reviewed blindly by an independent consultant radiologist. RESULTS: A total of 403 barium enemas were performed, of which 38 demonstrated a CRC (9%). In those patients diagnosed with CRC, nine (24%) had an abnormality on thoracic CT. Four patients with positive thoracic CTs had chemotherapy and or radiotherapy with no surgery. One patient underwent colectomy, and 2 patients who had primary lung tumours as opposed to metastases also underwent colectomies. One patient received palliative care only. In addition, one of the patients underwent multiple, non-diagnostic thoracic investigations prior to a diagnosis of sarcoidosis being made and then proceeding to surgery. An independent consultant radiologist reviewed seven out of the nine CXRs of patients with an abnormality on thoracic CT without knowledge of the clinical diagnosis, and reported three of the CXRs to be normal. CONCLUSIONS: Thoracic CT appears to improve the accuracy of pulmonary staging in CRC allowing a more appropriate level of intervention. However, CT is likely to identify more benign radiological abnormalities than CXR alone, and investigations should not occur to the detriment of treating the primary tumour.

Fast-track barium enema: meeting the two-week wait rule for patients with suspected colorectal cancer.

OBJECTIVES: To meet the introduction of the two-week wait (TWW) rule for patients with suspected colorectal cancer, a fast-track barium enema (FTBE) service was set up. This study was conducted to evaluate the success of this approach in preparation for meeting the forthcoming targets on waiting times to treatment from referral and diagnosis. METHODS: All patients were offered a double-contrast barium enema within two-weeks, except those with a palpable rectal mass. FTBE were double-reported by specialist gastrointestinal radiologists. Patients with a suspected malignancy were booked for an urgent staging CT and outpatient appointment, whilst the remaining patients were referred back to their general practitioner with a report. Prospective data were collected and two 16-month periods analysed. RESULTS: Three hundred and nine patients had a FTBE over the first 16-month period and 277 (89.6%) were seen within two-weeks. Mean times from initial referral to staging CT and first outpatient appointment were 30.7 and 36.0 days, respectively. Cancer was confirmed histologically in 32 (10.4%) patients. Of 267 patients without a malignancy, 46 (17.2%) were referred back to the colorectal outpatient or endoscopy service within 6-months. The number of referrals increased with time from a mean of 19.3 per month in the first period to 27.8 in the second, but the percentage with a suspected malignancy remained similar at 13.6% and 10.1%, respectively. CONCLUSION: FTBE diagnosed malignancy accurately and facilitated rapid staging. The TWW target was met in almost 90% of patients, whilst the impact on the colorectal outpatient and endoscopy service was minimized.

Mucin gene expression in the ileoanal reservoir is altered and may be relevant to the risk of inflammation and dysplasia.

BACKGROUND: Adaptive colonic phenotypic change of the ileal mucosa is a feature of the ileoanal reservoir (IAR) with time, as described by mucin glycoprotein and histological analysis. Mucin gene expression is altered in colorectal neoplasia and inflammatory bowel disease but little is known of its expression in the IAR. AIMS: To examine the changes in mucin gene expression contributing to mucosal protection of the IAR against a background of known changes occurring in inflammatory disease and colorectal neoplasia. PATIENTS: Paraffin embedded specimens from 29 "W" and 11 "J" ileoanal reservoirs were studied. Colonic and ileal control tissue was obtained from normal resection margins. METHODS: Mucin mRNA was detected by in situ hybridisation using [(35)S]dATP labelled oligonucleotide probes. Mucin core protein was detected by immunohistochemistry. RESULTS: There was no change in mRNA expression of MUC1-4 in the IAR compared with ileal controls but there was a decrease in the protein product of MUC1 and MUC3. No mRNA transcripts of MUC5AC, 5B, or 6 were detected but protein product of MUC5AC and MUC6 was detected. Both cases of MUC6 positivity and 1/5 cases of MUC5AC positivity were confined to the ulcer associated cell lineage. No dysplasia was detected. CONCLUSIONS: There is a change in the pattern of the membrane associated mucins MUC1 and MUC3, part of which is in keeping with changes described in colorectal neoplasia. A small number of cases demonstrated mucin gene changes (MUC5AC) which are seen in early neoplasia and this may provide a valuable monitor for such changes in IAR surveillance.

Differential expression of the chromosome 11 mucin genes in colorectal cancer.

The four secretory mucin genes clustered on chromosome 11, MUC2, MUC5AC, MUC5B and MUC6, were screened in 37 patients with cancers in the left hemi-colon or rectum and 10 normal rectal controls. The mucin genes were detected by in situ hybridization using oligonucleotide probes to the variable number tandem repeat (VNTR) sequences, while the proteins were stained with non-VNTR (MUC2, MUC5AC and MUC5B) or VNTR (MUC6) antibodies. Low levels of MUC2 mRNA were detected in non-mucinous adenocarcinomas (5/27) while a higher proportion of mucinous carcinomas (4/9) was positive. All 25 cases of adjacent normal tissue expressed MUC2 mRNA. No transcripts for MUC5AC, MUC5B or MUC 6 were detected in any of these specimens. MUC2 protein product was detected immunohistochemically in 34/36 carcinoma specimens, with no change from normal controls. There was de novo expression of MUC5AC in 23/36 carcinomas. No MUC5B or MUC6 protein was detected. No difference in MUC2 and MUC5AC protein was found between mucinous and non-mucinous carcinomas. The level of MUC2 was increased in moderately differentiated cancers compared with normal controls and decreased in the poorly differentiated group. Decreased MUC2 was found in poorly differentiated compared with moderately differentiated tumours. More MUC5AC protein was detected in well and moderately differentiated tumours than in poorly differentiated tumours and in all tumours relative to controls. The pattern of MUC2 staining in cancers was different from control tissue, with strong staining in the perinuclear region and none in goblet cell vesicles. MUC5AC staining was mainly detected in the cytoplasm. Poor detection of MUC2 and MUC5AC mRNA and associated strong staining for the total protein suggests altered biosynthesis and processing, leading to the characteristic subcellular distribution. Hence, change in the synthesis of MUC2 and the de novo appearance of MUC5AC in colorectal carcinomas may be significant events in the adenoma-carcinoma sequence, with possible implications for tumour prognosis.

Early enteral feeding versus "nil by mouth" after gastrointestinal surgery: systematic review and meta-analysis of controlled trials.

OBJECTIVE: To determine whether a period of starvation (nil by mouth) after gastrointestinal surgery is beneficial in terms of specific outcomes. DESIGN: Systematic review and meta-analysis of randomised controlled trials comparing any type of enteral feeding started within 24 hours after surgery with nil by mouth management in elective gastrointestinal surgery. Three electronic databases (PubMed, Embase, and the Cochrane controlled trials register) were searched, reference lists checked, and letters requesting details of unpublished trials and data sent to pharmaceutical companies and authors of previous trials. MAIN OUTCOME MEASURES: Anastomotic dehiscence, infection of any type, wound infection, pneumonia, intra-abdominal abscess, length of hospital stay, and mortality. RESULTS: Eleven studies with 837 patients met the inclusion criteria. In six studies patients in the intervention group were fed directly into the small bowel and in five studies patients were fed orally. Early feeding reduced the risk of any type of infection (relative risk 0.72, 95% confidence interval 0.54 to 0.98, P=0.036) and the mean length of stay in hospital (number of days reduced by 0.84, 0.36 to 1.33, P=0.001). Risk reductions were also seen for anastomotic dehiscence (0.53, 0.26 to 1.08, P=0.080), wound infection, pneumonia, intra-abdominal abscess, and mortality, but these failed to reach significance (P>0.10). The risk of vomiting was increased among patients fed early (1.27, 1.01 to 1.61, P=0.046). CONCLUSIONS: There seems to be no clear advantage to keeping patients nil by mouth after elective gastrointestinal resection. Early feeding may be of benefit. An adequately powered trial is required to confirm or refute the benefits seen in small trials.

Abnormal subcellular distribution of mature MUC2 and de novo MUC5AC mucins in adenomas of the rectum: immunohistochemical detection using non-VNTR antibodies to MUC2 and MUC5AC peptide.

Anti-mucin variable number tandem repeat (VNTR) antibodies have been used previously to demonstrate the de novo presence of MUC5AC and MUC6 mucin in colorectal adenomas and increased synthesis of MUC2, the major secreted mucin in normal colorectal mucosa. Here we examined secreted mucins in tubular, tubulovillous and villous adenomas of the rectum using non-VNTR antibodies designed to assess mature mucin. Mucin gene messenger RNAs were detected by in situ hybridization. The anti-MUC2 non-VNTR antibody in the goblet cells of adenomas revealed a staining pattern of increased cytoplasmic, Golgi and membrane staining with no change in goblet vesicle reactivity compared with normal controls. In addition, blank goblet cell vesicle immunostaining for MUC2 was found in the transitional mucosa adjacent to all types of adenoma. Although a trend to overexpression of MUC2 was observed with in situ hybridization this was not detected with immunohistology. De novo synthesis of MUC5AC, but not MUC5B or MUC6 mucin was seen in all adenomas and transitional mucosa using immunohistochemistry. There was no correlation of MUC2 or MUC5AC mucin with polyp size or the grade of dysplasia using the non-VNTR antibodies. This study demonstrates that anti-mucin non-VNTR antibodies reveal a different subcellular-localization in rectal adenomas compared with normal colorectal mucosa. Further, this pattern is in contrast to that reported for anti-mucin VNTR antibodies. Combined use of these reagents may benefit future assessment of these cancers.

Coordinated localisation of mucins and trefoil peptides in the ulcer associated cell lineage and the gastrointestinal mucosa.

BACKGROUND AND AIMS: Trefoil factor family (TFF) peptides and the chromosome 11p15.5 mucin glycoproteins are expressed and secreted in a site specific fashion along the length of the gastrointestinal tract. Evidence for coexpression of mucins and trefoil peptides has been suggested in numerous gastrointestinal mucosal pathologies. The ulcer associated cell lineage (UACL) occurs at sites of chronic ulceration in Crohn's disease, expresses all three trefoil peptides, and is implicated in mucosal restitution. We tested the hypothesis that individual trefoil peptides are uniquely localised with specific mucins in the UACL and normal gastrointestinal epithelia. METHODS: Expression of mucin genes in the UACL from small bowel tissue of patients with Crohn's disease was detected by in situ hybridisation, and localisation of the products by immunohistochemistry. Colocalisation of mucins and trefoil peptides was demonstrated by immunofluorescent colabelling in UACL and normal gastrointestinal epithelia. RESULTS: MUC5AC and TFF1 were colocalised in distal ductular and surface elements of the UACL and in foveolar cells of the stomach, whereas MUC6 and TFF2 were colocalised to acinar and proximal ductular structures in the UACL, in the fundus and deep antral glands of the stomach, and in Brunner's glands of the duodenum. MUC5B was found sporadically throughout the UACL and gastric body. MUC2 was absent from the UACL, Brunner's glands, and stomach. MUC2 and TFF3 were colocalised throughout the large and small bowel mucosa. CONCLUSIONS: The UACL has a unique profile of mucin gene expression. Coordinated localisation of trefoil peptides and mucins in UACL and normal gastrointestinal epithelia suggests they may assist each others' functions in protection and repair of gastrointestinal mucosa.

Lack of mucin MUC5AC field change expression associated with tubulovillous and villous colorectal adenomas.

BACKGROUND: MUC5AC is a secreted mucin aberrantly expressed by polypoid colorectal adenomas. It has been hypothesised that the "normal" surrounding colorectal mucosa expresses MUC5AC as a field change phenomenon that can be used to predict adenoma recurrence following resection. AIM: To determine if there is a field change of de novo MUC5AC expression in histologically normal rectal mucosa adjacent to villous and tubulovillous adenomas, and thus whether MUC5AC expression can be used as a marker of early tumour recurrence. METHODS: In a prospective cohort study paired mucosal biopsies of adenomatous and macroscopically "normal" mucosa were obtained from 11 patients with villous and 11 patients with tubulovillous adenomas who underwent primary resection for purpose of cure. The tissues were studied to determine MUC5AC gene expression by immunohistochemistry and in situ hybridisation. Patients were followed up by flexible sigmoidoscopy to detect the presence of early local recurrence. RESULTS: 10 villous adenomas showed mature MUC5AC glycoprotein and all 11 expressed MUC5AC mRNA. Five tubulovillous adenomas showed mature MUC5AC glycoprotein and 10 expressed MUC5AC mRNA. Neoexpression of the MUC5AC mucin gene was not detected in any of the mucosal biopsies taken adjacent to either villous or tubulovillous adenomas, even in three patients with early, locally recurrent disease. CONCLUSIONS: Aberrant MUC5AC gene expression is not a "field change" in the colorectal mucosa in patients with rectal adenomas and therefore cannot be used to predict local recurrence of villous and tubulovillous adenomas.

Vitamin D receptor expression in colorectal cancer.

AIMS: To determine whether the vitamin D receptor is expressed in colorectal cancer, and its relation to stage of disease. METHODS: Paraffin embedded sections of colorectal cancer from 30 patients who had undergone surgery were studied. Immunohistochemistry using the specific monoclonal antibody 9A7 gamma directed against the nuclear vitamin D receptor was used to identify receptors for the active metabolite of vitamin D3 (1,25-dihydroxyvitamin D3). RESULTS: Microscopically normal human colorectal epithelium showed vitamin D receptor expression predominantly in the mid and upper crypts. All the colorectal cancer tissue studied showed vitamin D receptor expression, with a median of 25.3 (range 10.1 to 43.7) cells/graticule field (x 400). Although vitamin D receptor staining was heterogeneous within the individual cancers, neither Dukes stage nor the degree of differentiation appeared to influence expression of the receptor. CONCLUSIONS: Colorectal cancer tissue expresses the nuclear vitamin D receptor and this could act as a potential therapeutic target for synthetic vitamin D3 differentiating agents.

Unacceptably high site variability in postmortem blood alcohol analysis.

Blood alcohol concentration is a frequently requested test in forensic pathology. The variability of this value was studied by measuring the blood alcohol concentration from six sites in nine subjects at necropsy in whom alcohol was the implicated cause of death. There were small consistent differences in the blood alcohol concentrations between the sites in the nine subjects (p < 0.04). Calculation of the mean blood:vitreous humour alcohol concentration ratio (B:V ratio) showed that vitreous humour alcohol concentration most closely reflected the concentration at the femoral vein (B:V ratio = 0.94, r = 0.98), which is considered the optimal site for blood alcohol measurement. The correlation of left heart blood with femoral blood was lower compared with the other sites. There is a potential for an unacceptably large variation in the postmortem measurement of blood alcohol within each subject.