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M W Reed

Publications and source records attributed to M W Reed.

At least 19 recordsLinked to original sources

Interleukin gene polymorphisms and breast cancer: a case control study and systematic literature review.

BACKGROUND: Interleukins and cytokines play an important role in the pathogenesis of many solid cancers. Several single nucleotide polymorphisms (SNPs) identified in cytokine genes are thought to influence the expression or function of these proteins and many have been evaluated for their role in inflammatory disease and cancer predisposition. The aim of this study was to evaluate any role of specific SNPs in the interleukin genes IL1A, IL1B, IL1RN, IL4R, IL6 and IL10 in predisposition to breast cancer susceptibility and severity. METHODS: Candidate single nucleotide polymorphisms (SNPs) in key cytokine genes were genotyped in breast cancer patients and in appropriate healthy volunteers who were similar in age, race and sex. Genotyping was performed using a high throughput allelic discrimination method. Data on clinico-pathological details and survival were collected. A systematic review of Medline English literature was done to retrieve previous studies of these polymorphisms in breast cancer. RESULTS: None of the polymorphisms studied showed any overall predisposition to breast cancer susceptibility, severity or to time to death or occurrence of distant metastases. The results of the systematic review are summarised. CONCLUSION: Polymorphisms within key interleukin genes (IL1A, IL1B, IL1RN, IL4R, IL6 and IL10 do not appear to play a significant overall role in breast cancer susceptibility or severity.

Aged↗

Ischemic vascular disease and solid cancers: opposing ends of the angiogenic spectrum?

Angiogenesis is a key pathway crucial to the patho-physiology of both vascular disease and solid cancer. In physiological conditions, a fine balance of pro- and anti-angiogenic factors is maintained as part of normal homeostatic mechanisms. It is widely accepted that excess angiogenesis influences the development or progression of tumours whilst insufficient angiogenesis may predispose to ischemic vascular disease. Although there are some factors, which predispose to both cancers and vascular disease, we believe there is a reasonable body of literature that suggests an inverse association between the two. We hypothesise that pro-angiogenic and anti-angiogenic phenotypes exist in the population. This may be due to a combination of underlying genetic variations and/or environmental factors. Pro-angiogenic phenotypes would have increased susceptibility to solid cancers and decreased predisposition to cardiovascular diseases and vice versa with the anti-angiogenic phenotypes. We propose that genetic and environmental factors causing a shift in the balance of angiogenesis will predispose individuals towards one group of pathologies while protecting them from another. Evaluation of this hypothesis will in the first instance involve carefully designed large population based observational studies to determine if an inverse relationship exists between the predisposition to ischemic vascular disease and the predisposition to solid cancer. Further detailed study of the pathways and underlying mechanisms of angiogenesis especially in disease states would facilitate better understanding of its regulation. Evaluation and validation of molecular markers that affect the 'angiogenesis pathway' may be helpful in determining the angiogenic potential of individual subjects. Determining where individuals lie along this spectrum may have a potential role in the prediction and stratification of risk of cancer and vascular disease. Modifying risk for patients at high risk of disease at the two opposing ends of the spectrum may then be possible by either lifestyle or dietary alterations or drugs targeting the angiogenic pathway.

Angiogenesis Inhibitors↗

Surgery versus primary endocrine therapy for operable primary breast cancer in elderly women (70 years plus).

BACKGROUND: Several studies have evaluated the clinical effectiveness of endocrine therapy alone in women aged 70 years or over and who are fit for surgery. OBJECTIVES: To identify and review the evidence from randomised trials comparing primary endocrine therapy (endocrine therapy alone) to surgery, with or without adjuvant endocrine therapy, in the management of women aged 70 years or over with operable breast cancer. SEARCH STRATEGY: The Cochrane Breast Cancer Group Specialised Register was searched on 21st August 2003 using the codes for "early breast cancer", "endocrine therapy", "psychosocial" or "surgery". Details of the search strategy applied to create the register and the procedure used to code references are described in the Cochrane Breast Cancer Group module on The Cochrane Library. SELECTION CRITERIA: Randomised trials comparing primary endocrine therapy with surgery, with or without adjuvant endocrine therapy, in the management of women aged 70 years or over with early breast cancer and who are fit for surgery. DATA COLLECTION AND ANALYSIS: Studies were assessed for eligibility and quality, and data from published trials were extracted by two independent reviewers. Hazard ratios were derived for time-to-event outcomes, where possible, and a fixed-effect model was used for meta-analysis. Toxicity and quality-of-life data were extracted, where present. Where outcome data were not available, trialists were contacted and unpublished data requested. MAIN RESULTS: Seven eligible trials were identified of which six had published time-to-event data and one was published only in abstract form with no usable data. The quality of the allocation concealment was adequate in three studies and unclear in the remainder. In each case the endocrine therapy used was tamoxifen.Data, based on an estimated 869 deaths in 1571 women, were unable to show a statistically significant difference in favour of either surgery or primary endocrine therapy in respect of overall survival. However, there was a statistically significant difference in terms of progression-free survival, which favoured surgery with or without endocrine therapy.The hazard ratios (HR) for overall survival were: 0.98 (95% confidence interval (CI) 0.74 to 1.30, P value 0.9) for surgery alone versus primary endocrine therapy; 0.86 (95% CI 0.73 to 1.00, P value 0.06) for surgery plus endocrine therapy versus primary endocrine therapy. The HRs for progression-free survival were: 0.55 (95% CI 0.39 to 0.77, P value 0.0006) for surgery alone versus primary endocrine therapy; 0.65 (95% CI 0.53 to 0.81, P value 0.0001) for surgery plus endocrine therapy versus primary endocrine therapy (each comparison based on only one trial). Tamoxifen-related adverse effects included hot flushes, skin rash, vaginal discharge, indigestion, breast pain, sleepiness, headache, vertigo, itching, hair loss, cystitis, acute thrombophlebitis, nausea, and indigestion. Surgery-related adverse effects included paresthesia on the ipsilateral arm and lateral thoracic wall in those who had axillary clearance. One study suggested that those undergoing surgery suffered more psychosocial morbidity at three months postsurgery, although this difference had disappeared by two years. AUTHORS' CONCLUSIONS: Primary endocrine therapy should only be offered to women with oestrogen receptor (ER) positive tumours who are unfit for or who refuse surgery. In a cohort of women with significant co-morbid disease and ER-positive tumours it is possible that primary endocrine therapy may be a superior option to surgery. Trials are needed to evaluate the clinical effectiveness of aromatase inhibitors as primary therapy for an infirm older population with ER-positive tumours.

Aged↗

Publication of surgical abstracts in full text: a retrospective cohort study.

INTRODUCTIONAbstracts presented at national and international scientific meetings are an important educational resource. However, the work is not peer reviewed and little is known about the quality or validity of the presented results and the fate of such abstracts.MATERIALS AND METHODSThis is a retrospective cohort study of abstracts presented to the 1997 annual meeting of the Association of Surgeons of Great Britain and Ireland. We examined the rates of full-text publication, time to publication, factors influencing publication, inconsistencies between presented and subsequently published manuscripts, and reasons for non-publication of abstracts.RESULTSOf the 241 abstracts presented, 136 (56.4%) were published at a median duration of 18 months. Multicentre studies had a greater tendency to subsequent publication and studies involving academic centres predicted publication in a high impact factor journal. Inconsistencies between presented and published abstracts were common and were significantly associated with delayed publication. Oral and poster presentations were equally likely to be published. Reasons for non-submission of presented abstracts included lack of time, low priority to publish, perceived methodological limitations, lack of novelty of findings and co-investigators leaving the organisation.CONCLUSIONSMore than half of the work presented at a national surgical meeting in the UK has been subsequently published. Various factors that influence the process of publication and remediable causes for non-publication have been identified.

Journal Article↗

Candidate gene polymorphisms in solid cancers.

Accumulation of information from scientific advances in genetics and biotechnology has accelerated research investigating the inherent individual variation in disease susceptibility and severity. Gene polymorphisms, in particular single nucleotide polymorphisms, are being evaluated for their role in multi-factorial diseases such as cancer and inflammation. Most surgical diseases are multi-factorial and a better understanding and utilization of the information gained from such studies by clinicians/surgeons is likely to favorably influence patient outcome. In this article, we illustrate the types of genetic variation and the complexities involved in their study and discuss their potential in predicting both the occurrence and outcomes of solid cancers.

Genetic Predisposition to Disease↗

An audit of the management of soft tissue sarcoma within a health region in the UK.

AIMS: Soft tissue sarcomas are rare and heterogeneous tumours only occasionally seen by most individual clinicians. Early recognition, appropriate referral and timely investigations markedly improve outcomes. Our aim was to retrospectively assess the referral patterns, investigation, surgery and outcomes of patients with soft tissue sarcoma in the Trent region of the UK. METHODS: Two hundred and four patients with soft tissue sarcoma registered with the Trent Cancer Registry in 1995-1997 were first studied. Clinical details, tumour characteristics, presentation, management and follow-up were recorded from the case notes and analysed.A further group of 40 patients referred to a single cancer centre in 1999 were audited to establish whether there had been any improvements/changes over the 2 years, since the completion of the first audit. RESULTS: In the first audit, 49.5% were first referred to general surgeons and 16% to orthopaedic surgeons. Only 15% of patients fit for surgery were referred to a surgeon with a specialist sarcoma interest prior to definitive exploration. Of the deep tumours, 64% had a preoperative biopsy and only 68% had a scan before biopsy or definitive surgery. Tumour grade, completeness of excision and site of the sarcoma influenced survival. The second audit performed on patients treated in 1999 showed only a marginal improvement in management when compared to the first audit.

Abdominal Neoplasms↗

Audit of compliance to adjuvant chemotherapy and radiotherapy guidelines in breast cancer in a cancer network.

The North Trent Cancer Network Breast Group in the United Kingdom revised its adjuvant treatment guidelines in breast cancer management in 1998. We aimed to check the compliance to the guidelines, 8 months after their introduction. Data were collected, retrospectively, from the medical records of patients with invasive breast cancer who underwent definitive surgery (in a 3-month period) in different cancer units and the cancer centre within the North Trent Cancer Network. The overall compliance to treatment guidelines was 82% (90% and 74% for chemotherapy and radiotherapy, respectively), which was similar across the network. In 5% of cases, compliance could not be determined. On case review, 22% of the non-compliant incidents were justified and 16% seemed to be due to variation in guideline interpretation. We discuss the possible reasons for non-compliance and show a need to periodically monitor compliance to adjuvant treatment guidelines.

Antineoplastic Combined Chemotherapy Protocols↗

Minor groove binder-conjugated DNA probes for quantitative DNA detection by hybridization-triggered fluorescence.

Here we describe the properties of a novel class of oligonucleotide probes capable of sensitive hybridization-triggered fluorescence. These fluorogenic probes, known commercially as MGB Eclipse probes, are characterized by having a conjugated minor groove binder (MGB) ligand at the 5'-end and a fluorophore at the 3'-end. Additionally, they have an efficient quencher moiety at the 5'-end that is useful with a wide variety of fluorescent dyes. Fluorescence of the single-stranded MGB Eclipse probe is efficiently quenched by the interaction of the terminal dye and quencher groups when not hybridized. Upon hybridization to a complementary target, the MGB molecule folds into duplex and hyper-stabilizes it, allowing the use of shorter, more specific probe sequences. The 5'-MGB-quencher group also prevents nuclease digestion by Taq DNA polymerase during PCR. Because of the hybridization-triggered fluorescence and the excellent specificity imparted by the MGB, these 5'-MGB Eclipse probes have great versatility for real-time PCR applications. The high sensitivity and specificity are illustrated using single nucleotide polymorphism detection, viral load determination, and gene expression analysis.

DNA↗

Attachment of benzaldehyde-modified oligodeoxynucleotide probes to semicarbazide-coated glass.

Attachment of oligodeoxynucleotides (ODNs) containing benzaldehyde (BAL) groups to semicarbazide-coated glass (SC-glass) slides is described. 5'-BAL-ODNs are prepared using automated DNA synthesis and an acetal-protected BAL phosphoramidite reagent. The hydrophobic protecting group simplifies purification of BAL-ODNs by reverse phase HPLC and is easily removed using standard acid treatment. The electrophilic BAL-ODNs are stable in solution, but react specifically with semicarbazide groups to give semicarbazone bonds. Glass slides were treated with a semicarbazide silane to give SC-glass. BAL-ODNs are coupled to the SC-glass surface by a simple one-step procedure that allows rapid, efficient and stable attachment. Hand-spotted arrays of BAL-ODNs were prepared to evaluate loading density and hybridization properties of immobilized probes. Hybridization to radiolabeled target strands shows that at least 30% of the coupled ODNs were available for hybridization at maximum immobilization density. The array was used to probe single nucleotide polymorphisms in synthetic DNA targets, and PCR products were correctly genotyped using the same macroarray. Application of this chemistry to manufacturing of DNA microarrays for sequence analysis is discussed.

Benzaldehydes↗

Effects of genotypically different strains of Helicobacter pylori on human microvascular endothelial cells in vitro.

Helicobacter pylori induces a number of disturbances in rodent gastric microcirculation in vivo. These events may result from direct necrotic or apoptotic damage to endothelial cells. This study therefore aimed to investigate the effects of genotypically different H. pylori strains on microvascular endothelial cell (MVEC) viability in vitro. Four H. pylori extracts were prepared from strains with different cagA or vacA status. MVECs were plated into 96-well plates and coincubated with 50 microl of extract or vehicle for 24, 48, 72, or 96 hr. An MPP assay quantified overall MVEC viability. The dual labeling of MVECs with propidium iodide and Hoechst 33342 distinguished between necrotic and apoptotic cell death, respectively, and allowed total number of viable cells to be determined. All strains of H. pylori decreased cell viability after 72 and 96 hr. Neither necrosis or apoptosis was observed. Counting total number of viable cells revealed decreased cell proliferation with all strains when compared to controls, again reaching significance at 72 and 96 hr. In conclusion, both the MTT assay and the diret cell counting technique demonstrated that all H. pylori strains induced cytostatic but not cytotoxic effects on MVECs. This suggests that microcirculatory disturbances observed in vivo may not be the result of direct endothelial cell damage. However, inhibition of angiogenesis may explain why ulcer healing is delayed in H. pylori-infected patients.

Apoptosis↗

Mismatch between general surgical trainees' sub-specialist interests and advertised jobs: a cause for concern?

The main aim of this study was to establish the primary sub-specialist interest of a group of senior general surgical trainees and compare these results with the required sub-specialist interests in consultant vacancies advertised in the British Medical Journal between 3.1.98 and 25.12.99. Colorectal surgery was the most popular sub-specialty amongst trainees (29.4%) followed by upper gastrointestinal/hepato-pancreato-biliary (UGI/HPB) (27.2%) and vascular surgery (24.3%). The least popular sub-specialties were breast/endocrine (11.4%) and transplant (2.9%). A total of 324 consultant jobs were advertised, with the sub-specialist interest required as follows: Colorectal (25.6%), breast/endocrine (23.5%), vascular (20.4%), UGI/HPB (12%) and transplant (5.6%). Although this study only covers a two-year period, there are obvious discrepancies between trainees' sub-specialist interests and consultant vacancies. Whilst the jobs to trainees ratios are well matched in colorectal and vascular surgery, it appears that there are not enough transplant or breast trainees and too many UGI/HPB trainees for the number of jobs available. This problem needs urgent attention to avoid service shortfalls in unpopular sub-specialties and to avoid training people for jobs that do not exist.

Advertising↗

Quantitative reverse transcription-polymerase chain reaction to study mRNA decay: comparison of endpoint and real-time methods.

Four quantitative reverse transcription-PCR (RT-PCR) methods were compared to evaluate the time course of mRNA formation and decay. Mouse fibroblasts (NIH 3T3) transfected with the human beta-globin open reading frame/c-myc 3'-untranslated region chimeric gene under control of the c-fos promoter (fos-glo-myc) were used for serum-inducible transcription. The amount of fos-glo-myc mRNA, relative to beta-actin, was measured by quantitative, RT-PCR at various times following the addition of serum to serum-starved fibroblasts transfected with the chimeric gene. Both endpoint (band densitometry and probe hybridization) and real-time (SYBR green and TaqMan) PCR methods were used to assay the identical cDNA. The real-time methods produced a 4- to 5-log dynamic range of amplification, while the dynamic range of the endpoint assays was 1-log. The real-time and probe hybridization assays produced a comparable level of sensitivity that was considerably greater than band densitometry. The coefficient of variation from 22 replicate PCR reactions was 14.2 and 24.0% for the SYBR green and TaqMan detection, respectively, and 44.9 and 45.1% for the band densitometry and probe hybridization assays, respectively. The rank order for the values of r(2) obtained from the linear regression of the first-order mRNA decay plots was SYBR green > TaqMan > probe hybridization > band densitometry. Real-time PCR is more precise and displays a greater dynamic range than endpoint PCR. Among the real-time methods, SYBR green and TaqMan assays produced comparable dynamic range and sensitivity while SYBR green detection was more precise and produced a more linear decay plot than TaqMan detection.

3T3 Cells↗

3'-minor groove binder-DNA probes increase sequence specificity at PCR extension temperatures.

DNA probes with conjugated minor groove binder (MGB) groups form extremely stable duplexes with single-stranded DNA targets, allowing shorter probes to be used for hybridization based assays. In this paper, sequence specificity of 3'-MGB probes was explored. In comparison with unmodified DNA, MGB probes had higher melting temperature (T(m)) and increased specificity, especially when a mismatch was in the MGB region of the duplex. To exploit these properties, fluorogenic MGB probes were prepared and investigated in the 5'-nuclease PCR assay (real-time PCR assay, TaqMan assay). A 12mer MGB probe had the same T(m)(65 degrees C) as a no-MGB 27mer probe. The fluorogenic MGB probes were more specific for single base mismatches and fluorescence quenching was more efficient, giving increased sensitivity. A/T rich duplexes were stabilized more than G/C rich duplexes, thereby leveling probe T(m)and simplifying design. In summary, MGB probes were more sequence specific than standard DNA probes, especially for single base mismatches at elevated hybridization temperatures.

Base Pair Mismatch↗

The role of cyclooxygenase 2 in ulcerative colitis-associated neoplasia.

Cyclooxygenase 2 (COX-2) overexpression has been described in sporadic colonic neoplasia, but its role in ulcerative colitis (UC) neoplastic progression remains unexplored. Although the specific role of cyclooxygenase in colonic neoplasia is uncertain, its inhibition by nonsteroidal anti-inflammatory drugs decreases the risk of sporadic colonic adenocarcinoma and causes regression of adenomas in familial adenomatous polyposis. To investigate the role of COX-2 in UC-associated neoplasia, we assessed COX-2 protein and mRNA expression throughout the spectrum of UC-associated neoplastic lesions in four total colectomy specimens, using immunocytochemistry and a novel TaqMan reverse transcriptase-polymerase chain reaction assay. The findings were correlated with DNA ploidy and inflammatory activity. We found COX-2 overexpression throughout the neoplastic spectrum in UC (P: < 0.0001, R:(2)=0.53), even in diploid samples that were negative for dysplasia. Overall, neoplastic change explained 53% of the variation in COX-2 expression, whereas inflammatory activity explained only 11%. COX-2 was overexpressed in all aneuploid samples and in 38% of diploid samples (P: = 0.0074). cDNA representational difference analysis was also performed and revealed that COX-2 mRNA was an up-regulated cDNA representational difference analysis difference product. COX-2 overexpression occurs early in UC-associated neoplasia, and the increase cannot be explained by inflammatory activity alone. The data suggest that COX-2-specific inhibitors may have a chemopreventative role in UC but the possibility that they could exacerbate UC inflammatory activity needs to be tested.

Adenocarcinoma↗

Mechanisms of Helicobacter pylori-induced rat gastric mucosal microcirculatory disturbances in vivo.

The exact mechanisms by which Helicobacter pylori infection results in gastric mucosal injury are unclear. However, it has been demonstrated that surface protein extracts of the bacterium can induce a number of disturbances within the rat gastric mucosal microcirculation, including platelet aggregation and macromolecular leakage (MML) of labeled albumin. This study aimed to determine the mechanisms involved in inducing these events using the technique of fluorescent in vivo microscopy. Male Wistar rats were pretreated with either ketotifen, a mast cell stabilizer (1 mg/kg), pyrilamine, an H1-receptor antagonist (30 mg/kg), hexanolamine-PAF, a PAF-receptor antagonist (10 microg/kg), L-arginine, the nitric oxide precursor (300 mg/kg) or vehicle, saline. Then 0.5 ml of H. pylori extract was administered to the exteriorized gastric mucosa of the anesthetized rat. Alterations in fluorescein-labeled albumin leak, vessel diameters, and acridine red-labeled leukocyte and platelet activity were determined over a 2-hr period. Saline pretreated animals demonstrated significant MML with a peak at 5 min (11%, P<0.02). This was prevented with ketotifen and pyrilamine, but not with hexanolamine-PAF (17.5%, P<0.05) and L-arginine (13%, P<0.05). Significant numbers of platelet emboli and thrombi were observed within mucosal capillaries and postcapillary venules with vehicle pretreatment; this was prevented with hexanolamine-PAF and L-arginine, but not with ketotifen and pyrilamine. In conclusion, these studies demonstrate that more than one mediator is involved in inducing the rat gastric mucosal microcirculatory disturbances associated with H. pylori administration. Mast cells and histamine are linked to MML, with PAF, probably not derived from mast cells, involved in platelet activation.

Animals↗

Effects of chronic administration of Helicobacter pylori extracts on rat gastric mucosal microcirculation in vivo.

The mechanisms by which Helicobacter pylori contributes to gastroduodenal injury are unclear. We have previously described platelet aggregation within rat gastric mucosal microcirculation following acute administration of H. pylori extracts. However, leukocyte activation was not observed. This study aimed to determine whether chronic administration of H. pylori could induce leukocyte activation. Rats were gavaged with either H. pylori or E. coli extracts or with distilled water three times daily at three-day intervals. Acridine red was used to quantitate gastric mucosal leukocyte/platelet activity using fluorescent in vivo microscopy. Further animals received additional acute H. pylori after 1 hr and recordings were made for a further 1 hr. Significant numbers of "flyers," "rollers," and adherent leukocytes were observed throughout the study in H. pylori animals. Only adherent leukocytes were observed following E. coli. Acute H. pylori induced a further significant increase in adherent leukocytes. Significant platelet thrombi were also present in H. pylori-treated animals. In conclusion, earlier studies demonstrated platelet aggregation but no leukocyte activation, which is in contrast to the current chronic studies. Platelet activation may be the initial response to H. pylori and involved in recruitment of leukocytes. These activated cells may contribute to the development of gastric mucosal damage.

Animals↗