Quantification of Serum Metabolites in Early Colorectal Adenomas Using Isobaric Labeling Mass Spectrometry.

A major challenge in reducing the death rate of colorectal cancer is to screen patients using low-invasive testing. A blood test shows a high compliance rate with reduced invasiveness. In this work, a multiplex isobaric tag labeling strategy coupled with mass spectrometry is adopted to relatively quantify primary and secondary amine-containing metabolites in serum for the discovery of metabolite level changes of colorectal cancer.

Conserved serum protein biomarkers associated with growing early colorectal adenomas.

A major challenge for the reduction of colon cancer is to detect patients carrying high-risk premalignant adenomas with minimally invasive testing. As one step, we have addressed the feasibility of detecting protein signals in the serum of patients carrying an adenoma as small as 6-9 mm in maximum linear dimension. Serum protein biomarkers, discovered in two animal models of early colonic adenomagenesis, were studied in patients using quantitative mass-spectrometric assays.

The conserved protective cyclic AMP-phosphodiesterase function PDE4B is expressed in the adenoma and adjacent normal colonic epithelium of mammals and silenced in colorectal cancer.

Conservation over three mammalian genera-the mouse, rat, and human-has been found for a subset of the transcripts whose level differs between the adenoma and normal epithelium of the colon. Pde4b is one of the triply conserved transcripts whose level is enhanced both in the colonic adenoma and in the normal colonic epithelium, especially adjacent to adenomas. It encodes the phosphodiesterase PDE4B, specific for cAMP.

Weaving a Tapestry from Threads Spun by Geneticists: The Series Perspectives on Genetics, 1987-2008.

The Perspectives column was initiated in 1987 when Jan Drake, Editor-in-Chief of GENETICS, invited Jim Crow and William Dove to serve as coeditors of "Anecdotal, Historical, and Critical Commentaries." As the series evolved over 21 years, under the guidance of Crow and Dove, the input of stories told by geneticists from many countries created a panorama of 20th-century genetics. Three recurrent themes are visible: how geneticists have created the science (as solitary investigators, in pairs, or in cooperative groups); how geneticists work hard, but find ways to have fun; and how public and private institutions have sustained the science of genetics, particularly in the United States.

Understanding Intratumoral Heterogeneity: Lessons from the Analysis of At-Risk Tissue and Premalignant Lesions in the Colon.

Advances in DNA sequencing have created new opportunities to better understand the biology of cancers. Attention is currently focused on precision medicine: does a cancer carry a mutation that is targetable with already available drugs? But, the timing at which multiple, targetable mutations arise during the adenoma to carcinoma sequence remains unresolved. Borras and colleagues identified mutations and allelic imbalance in at-risk mucosa and early polyps in the human colon.

Cholecalciferol or 25-hydroxycholecalciferol neither prevents nor treats adenomas in a rat model of familial colon cancer.

Background: Epidemiologic studies in humans have shown associations between greater sunlight exposure, higher serum 25-hydroxycholecalciferol [25(OH)D3] concentrations, and reduced colon cancer risk. However, results from a limited number of vitamin D supplementation trials in humans have not shown a protective effect.

Objective: We sought to determine whether adding to the diet increasing amounts of either 25(OH)D3, the stable metabolite measured in serum and associated with cancer risk, or cholecalciferol (vitamin D3), the compound commonly used for supplementation in humans, could reduce emergent adenomas (chemoprevention) or decrease the growth of existing adenomas (treatment) in the colons of vitamin D-sufficient rats carrying a truncation mutation of adenomatous polyposis coli (Apc), a model of early intestinal cancer.

Molecular epidemiology of rotavirus in cats in the United Kingdom.

Rotaviruses are leading causes of gastroenteritis in the young of many species. Molecular epidemiological studies in children suggest that interspecies transmission contributes to rotavirus strain diversity in people. However, population-based studies of rotaviruses in animals are few.

Sex disparity in colonic adenomagenesis involves promotion by male hormones, not protection by female hormones.

It recently has been recognized that men develop colonic adenomas and carcinomas at an earlier age and at a higher rate than women. In the Apc(Pirc/+) (Pirc) rat model of early colonic cancer, this sex susceptibility was recapitulated, with male Pirc rats developing twice as many adenomas as females. Analysis of large datasets revealed that the Apc(Min/+) mouse also shows enhanced male susceptibility to adenomagenesis, but only in the colon.

The utility of Apc-mutant rats in modeling human colon cancer.

Prior to the advent of genetic engineering in the mouse, the rat was the model of choice for investigating the etiology of cancer. Now, recent advances in the manipulation of the rat genome, combined with a growing recognition of the physiological differences between mice and rats, have reignited interest in the rat as a model of human cancer. Two recently developed rat models, the polyposis in the rat colon (Pirc) and Kyoto Apc Delta (KAD) strains, each carry mutations in the intestinal-cancer-associated adenomatous polyposis coli (Apc) gene.

The concentrations of EGFR, LRG1, ITIH4, and F5 in serum correlate with the number of colonic adenomas in ApcPirc/+ rats.

The development of noninvasive methods for early detection of colon cancer is critical for the successful management of this disease. Using a targeted quantitative proteomics technique, we assessed the ability of 12 serum proteins to detect the presence of colonic polyps in the Apc(Pirc) (/+) rat model of familial colon cancer. Serum protein candidates were selected from gene transcripts upregulated in colonic tumors of Apc(Pirc) (/+) rats and from a prior study of serum proteins differentially expressed in mice carrying intestinal adenomas.

A strategy to identify dominant point mutant modifiers of a quantitative trait.

A central goal in the analysis of complex traits is to identify genes that modify a phenotype. Modifiers of a cancer phenotype may act either intrinsically or extrinsically on the salient cell lineage. Germline point mutagenesis by ethylnitrosourea can provide alleles for a gene of interest that include loss-, gain-, or alteration-of-function.

A simple, quantitative method using alginate gel to determine rat colonic tumor volume in vivo.

Many studies of the response of colonic tumors to therapeutics use tumor multiplicity as the endpoint to determine the effectiveness of the agent. These studies can be greatly enhanced by accurate measurements of tumor volume. Here we present a quantitative method to easily and accurately determine colonic tumor volume.

Candidate serum biomarkers for early intestinal cancer using 15N metabolic labeling and quantitative proteomics in the ApcMin/+ mouse.

Current screening procedures for colorectal cancer are imperfect and highly invasive and result in increased mortality rates due to low compliance. The goal of the experiments reported herein is to identify potential blood-based biomarkers indicative of early stage intestinal cancers using the ApcMin/+ mouse model of intestinal cancer as an experimental system. Serum proteins from tumor-bearing ApcMin/+ mice were quantitatively compared to tumor-free Apc+/+ wild-type mice via in anima metabolic labeling with 14N/15N-labeled Spirulina algae and an LTQ Orbitrap mass spectrometer.

Detection and molecular characterisation of noroviruses in hospitalised children in Malawi, 1997-2007.

Despite the increasing recognition of noroviruses as major pathogens associated with community-acquired diarrhoea in children, there are few studies from Africa. Long-term surveillance studies of rotavirus gastroenteritis in Malawian children have provided an opportunity to undertake a study of the importance and epidemiological features of norovirus infection in this population. Faecal specimens were collected from children <5 years of age admitted to hospital with acute diarrhoea, as well as from a comparison group of diarrhoea-free children, in Blantyre, Malawi between 1997 and 2007.

Ljungan virus is endemic in rodents in the UK.

Ljungan virus is a recently identified member of the family Picornaviridae that was isolated from bank voles in Sweden. LjV has been associated with [corrected] type 1 diabetes-like symptoms and myocarditis in bank voles (Myodes glareolus), and it has been suggested that it has zoonotic potential. Here, we show for the first time that Ljungan virus is prevalent (20-27 % positive by PCR) in four species of UK rodent (Myodes glareolus [bank vole], Apodemus sylvaticus [wood mouse], Microtus agrestis [field vole] and Mus musculus [house mouse]).

Campylobacter infection in children in Malawi is common and is frequently associated with enteric virus co-infections.

Background: Campylobacter species are the most common cause of bacterial gastroenteritis in the developed world. However, comparatively few studies have determined the epidemiological features of campylobacteriosis in resource-poor settings.

Methods: A total of 1,941 faecal specimens collected from symptomatic (diarrhoeic) children and 507 specimens from asymptomatic (non-diarrhoeic) children hospitalised in Blantyre, Malawi, between 1997 and 2007, and previously tested for the presence of rotavirus and norovirus, was analysed for C.

Surveillance of rotavirus gastro-enteritis in children in Blantyre, Malawi.

Background: Rotavirus is a leading cause of acute gastro-enteritis in infants and young children worldwide. Previous studies of rotavirus gastro-enteritis in Malawi have documented a high disease burden with an extensive diversity of circulating rotavirus strains.

Methods: In anticipation of the introduction of national rotavirus vaccination, a 2-year surveillance study was undertaken in 2008 and 2009 of children in Blantyre seeking hospital care for acute gastro-enteritis.

Pathology of rodent models of intestinal cancer: progress report and recommendations.

In October 2010, a pathology review of rodent models of intestinal neoplasia was held at The Jackson Laboratory. This review complemented 2 other concurrent events: a workshop on methods of modeling colon cancer in rodents and a conference on current issues in murine and human colon cancer. We summarize the results of the pathology review and the committee's recommendations for tumor nomenclature.

G8 rotaviruses with conserved genotype constellations detected in Malawi over 10 years (1997-2007) display frequent gene reassortment among strains co-circulating in humans.

Rotavirus A, the most common cause of severe diarrhoea in children worldwide, occurs in five major VP7 (G) and VP4 (P) genotype combinations, comprising G1P[8], G2P[4], G3P[8], G4P[8] and G9P[8]. However, G8, a common bovine rotavirus genotype, has been reported frequently among children in African countries. Surveillance of rotavirus gastroenteritis conducted in a sentinel hospital in Blantyre, Malawi between 1997 and 2007 provided a rare opportunity to examine the whole genotype constellation of G8 strains and their evolution over time.

PCR based bronchoscopic detection of common respiratory pathogens in chronic cough: a case control study.

Background: Viral respiratory tract infection is the most frequent cause of acute cough and is reported at onset in about one third of patients with chronic cough. Persistent infection is therefore one possible explanation for the cough reflex hypersensitivity and pulmonary inflammation reported in chronic cough patients.

Methods: Bronchoscopic endobronchial biopsies and bronchoalveolar lavage cell counts were obtained from ten healthy volunteers and twenty treatment resistant chronic cough patients (10 selected for lavage lymphocytosis).

Regulated Expression of Chromobox Homolog 5 Revealed in Tumors of Apc(Min) (/+) ROSA11 Gene Trap Mice.

The gene-trap lacZ reporter insertion, ROSA11, in the Cbx5 mouse gene illuminates the regulatory complexity of this locus in Apc(Min) (/+) mice. The insertion site of the β-Geo gene-trap element lies in the 24-kb intron proximal to the coding region of Cbx5. Transcript analysis indicates that two promoters for Cbx5 flank this insertion site.

Molecular characterization of rotavirus strains detected during a clinical trial of a human rotavirus vaccine in Blantyre, Malawi.

The human, G1P[8] rotavirus vaccine (Rotarix™) significantly reduced severe rotavirus gastroenteritis episodes in a clinical trial in South Africa and Malawi, but vaccine efficacy was lower in Malawi (49.5%) than reported in South Africa (76.9%) and elsewhere.

Unusual norovirus and rotavirus genotypes in Ethiopia.

Background: Gastro-enteritis is associated with significant mortality in low- and middle-income countries, and rotavirus and norovirus are the principal viral agents implicated.

Aims: To investigate the molecular epidemiology and burden of disease associated with rotavirus and norovirus in children attending a health centre in Ethiopia.

Methods: A cross-sectional study was conducted in children attending a health centre in Awassa, southern Ethiopia.