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PubMed2003

beta-Catenin regulates vascular endothelial growth factor expression in colon cancer.

To evaluate whether beta-catenin signaling has a role in the regulation of angiogenesis in colon cancer, a series of angiogenesis-related gene promoters was analyzed for beta-catenin/TCF binding sites. Strikingly, the gene promoter of human vascular endothelial growth factor (VEGF, or VEGF-A) contains seven consensus binding sites for beta-catenin/TCF. Analysis of laser capture microdissected human colon cancer tissue indicated a direct correlation between up-regulation of VEGF-A expression and adenomatous polyposis coli (APC) mutational status (activation of beta-catenin signaling) in primary tumors. In metastases, this correlation was not observed. Analysis by immunohistochemistry of intestinal polyps in mice heterozygous for the multiple intestinal neoplasia gene (Min/+) at 5 months revealed an increase and redistribution of VEGF-A in proximity to those cells expressing nuclear beta-catenin with a corresponding increase in vessel density. Transfection of normal colon epithelial cells with activated beta-catenin up-regulated levels of VEGF-A mRNA and protein by 250-300%. When colon cancer cells with elevated beta-catenin levels were treated with beta-catenin antisense oligodeoxynucleotides, VEGF-A expression was reduced by more than 50%. Taken together, our observations indicate a close link between beta-catenin signaling and the regulation of VEGF-A expression in colon cancer.

Adenocarcinoma↗
PubMed1988

Ubiquitous expression of HLA-DR antigens on human small intestinal epithelium.

To clarify the frequency of the expression of HLA-DR antigens on the human small intestinal epithelium and the variation of such expression, 43 specimens (duodenum 16, jejunum 8, ileum 19; histologically normal 33, pathologic lesions 10) were studied for HLA-DR expression by indirect immunoperoxidase staining using monoclonal antibodies against HLA-DR antigens. All specimens reacted with anti-HLA-DR antibodies with minor variations. Most specimens showed decreasing intensity from the top of the villi toward the base of the villi and no staining in the crypt. In about half of the specimens, clear peripheral and cytoplasmic staining of the epithelial cells was observed. In some cases, the staining of the apical portion of the epithelium was patchy. The expression was unrelated to the lymph follicle. This ubiquitous expression of HLA-DR antigens on the small intestinal epithelium presents a striking contrast to an absence of the antigens on the normal large intestinal epithelium. A preliminary study on the pathologic lesions demonstrated the following changes in the expression of HLA-DR antigens; appearance of HLA-DR antigens on the crypt epithelium in Crohn's disease, loss of HLA-DR antigens on the epithelium covering the area of cell infiltration in macroglobulinemia and covering adenoma in familial polyposis coli.

Antibodies, Monoclonal↗
PubMed1995

Barnett continent intestinal reservoir. Multicenter experience with an alternative to the Brooke ileostomy.

PURPOSE: Since 1988, surgeons at five hospitals have been performing the Barnett continent intestinal reservoir (BCIR). The BCIR includes modifications to the original Kock pouch, designed to reduce the incidence of valve slippage and fistula formation. Principle modifications include an intestinal collar, an isoperistaltic valve, and a lateral pouch design. METHOD: This unique collaborative study includes 510 ulcerative colitis or familial polyposis patients, with a follow-up time from one to five years postoperatively. RESULTS: Ninety-two percent still have functioning reservoirs. Six and one-half percent have had their pouches removed and replaced with conventional Brooke ileostomies. Reoperation rate for major pouch-related complications (other than pouch removal) was 12.8 percent. These complications included slipped valve (6.3 percent), valve fistulas (4.5 percent), and pouch fistulas (6.3 percent). Several questions were administered to patients whose responses revealed a significant improvement in general quality of life, state of mind, and overall health. CONCLUSIONS: The BCIR represents a successful alternative to patients with a conventional Brooke ileostomy or those who are not candidates for the ileal pouch-anal anastomosis.

Adenomatous Polyposis Coli↗
PubMed1984

Diagnosis and treatment of cystic fibrosis. An update.

Cystic fibrosis is the most common fatal inherited disease of Caucasians. At present, cystic fibrosis accounts for most cases of chronic progressive pulmonary disease and for many other clinical features in the first three decades of life. Thus, it is a challenge to both pediatricians and internists, particularly chest physicians. The diagnosis is based on the triad of chronic obstructive pulmonary disease, pancreatic insufficiency, and increased levels of electrolytes in the sweat. The cardinal test for confirmation of the diagnosis is the "sweat test," which is an excellent discriminant for cystic fibrosis, even in adults. Ancillary features of cystic fibrosis may be of diagnostic assistance (eg, nasal polyposis, Pseudomonas aeruginosa in sputum, azoospermia, and others). Treatment of the pulmonary disease must be emphasized. Choice of antibiotics should be based on the results of sputum culture, but P aeruginosa is the most common pathogen. Removal of secretions by regular postural drainage and percussion is an integral part of the program. Pneumothorax, massive hemoptysis, cor pulmonale, and other complications may be encountered. Sinusitis is almost universal, and nasal polyposis is frequently present. Pancreatic insufficiency occurs in over 80 percent of the patients with cystic fibrosis and may result in intestinal malabsorption. Massive salt loss through the sweat in hot weather, a distinctive type of biliary cirrhosis without jaundice, gallbladder abnormalities, cholelithiasis, and diabetes mellitus also may be found. Of special importance are intestinal obstructive complications (meconium ileus in newborn infants with cystic fibrosis and intestinal obstruction due to fecal accumulation or intussusception in adults). Azoospermia is present in 95 percent of men and there is reduced fertility in women; however, pregnancy does occur in cystic fibrosis. This chronic and ultimately fatal disease produces a predictable set of psychosocial complications.

Adult↗
PubMed1986

Juvenile gastrointestinal polyposis or the infantile Cronkhite-Canada syndrome.

This is a report of a case of juvenile gastrointestinal polyposis consisting of widespread juvenile polyps encountered from the stomach into the rectum. Only few cases have been reported, and extra intestinal manifestations include clubbing of fingers, macrocephaly, hypotonia, hepatosplenomegaly, anemia, and protein-losing enteropathy. The outcome is usually dismal, the children barely becoming older than 2 years. Modern fibreoptic endoscopy with polypectomies performed via the upper and lower gastrointestinal intestinal tracts and via a midbowel ileostomy may offer a viable form of management.

Humans↗
PubMed1997

Homeosis and intestinal tumours in Cdx2 mutant mice.

In Drosophila, disturbing the expression of the homeobox gene caudal causes a severe disruption in body segmentation and global body patterning. There are three mouse homologues of Drosophila caudal: Cdx1 (ref. 2), Cdx2 (ref. 3) and Cdx4 (ref. 4). We have generated a null mutation of murine Cdx2 by homologous recombination. Cdx2 homozygote null mutants die between 3.5 and 5.5 days post coitum (d.p.c.). Cdx2 heterozygote mutants exhibit a variable phenotype, with many showing tail abnormalities or stunted growth. Skeletal analysis demonstrates a homeotic shift of vertebrae and compatible malformations of the ribs. Within the first three months of life, 90% of Cdx2 heterozygotes develop multiple intestinal adenomatous polyps, particularly in the proximal colon. These polyps occasionally contain areas of true metaplasia. In contrast to the surrounding intestinal epithelium, the neoplastic cells do not express Cdx2 from the remaining allele. These results suggest that Cdx2 mutation is the primary event in the genesis of some intestinal tumours.

Adenomatous Polyposis Coli↗
PubMed2003

Msh2 deficiency enhances somatic Apc and p53 mutations in Apc+/-Msh2-/- mice.

Inactivation of the adenomatous polyposis coli (Apc) gene by loss of the wild-type Apc allele (LOH) is a prerequisite for the development of intestinal adenomas in Msh2 proficient Min (Apc+/-Msh2+/+) mice. In contrast, adenomas from Msh2 deficient Min (Apc+/-Msh2-/-) mice are not usually associated with LOH. Given the role of Msh2 in post-replicative DNA repair, this study investigated whether Msh2 deficiency enhances somatic Apc and p53 mutations in Apc+/-Msh2-/- mice. Somatic Apc mutations (5/sample) were observed in the non-neoplastic intestinal mucosa from Apc+/-Msh2-/- mice but not from Min mice, suggesting that Msh2 deficiency is associated with a hypermutable state in the intestinal mucosa from Apc+/-Msh2-/- mice. Adenomas from Apc+/-Msh2-/- mice had a 2-fold higher rate of somatic Apc mutations (10/adenoma) than the non-neoplastic intestinal mucosa (5/sample), and did not demonstrate LOH. Truncating Apc mutations were observed in 82% of the adenomas from Apc+/-Msh2-/- mice and were not observed at all in the non-neoplastic intestinal mucosa. In contrast, in Min mice, all adenomas demonstrated LOH, had significantly less numbers of somatic Apc mutations (1.8 mutations/adenoma) compared with the adenomas from Apc+/-Msh2-/- mice, and harbored no truncating Apc mutations. These observations suggest that somatic Apc mutations, and not LOH, is a likely mechanism by which the Apc gene is inactivated in the development of adenomas in Apc+/-Msh2-/- mice in contrast to Min mice. Adenomas from Apc+/-Msh2-/- mice, but not from Min mice, also harbored somatic p53 mutations (mutation frequency of 45.5%), reflecting hypermutability associated with Msh2 deficiency. The nature and frequency of somatic Apc and p53 mutations in Apc+/-Msh2-/- mice suggest that many genomic sites, in addition to genes containing simple repeated sequences, are at risk of somatic mutations associated with Msh2 deficiency.

Adenoma↗
PubMed2003

Rofecoxib (Vioxx), a specific cyclooxygenase-2 inhibitor, is chemopreventive in a mouse model of colon cancer.

The ApcDelta716 knockout mouse develops hundreds of intestinal polyps and smaller numbers in the colon because of the truncation of the suppressor protein Apc. We show inhibition of polyposis in the ApcDelta716 mouse by rofecoxib (Vioxx), a specific cyclooxygenase-2 (COX-2) inhibitor. Both the number and size of polyps in the ApcDelta716 mouse were markedly reduced by rofecoxib (Vioxx) treatment at plasma concentrations similar to those achieved in humans with antiinflammatory concentrations of Vioxx. Sulindac, a dual cyclooxygenase-1/2 inhibitor, also diminished size and number of polyps but to a lesser extent than rofecoxib. The protein expression of COX-1 or COX-2 was unchanged by treatment with rofecoxib or sulindac because these agents inhibit enzyme activity and prostaglandin product formation rather than transcription of the COX genes. The proangiogenic protein vascular derived endothelial growth factor was decreased in polyps treated with rofecoxib, whereas membrane-associated beta-catenin increased in rofecoxib-treated polyps. DNA proliferation was decreased in polyps by both rofecoxib and sulindac treatment. Rofecoxib (Vioxx) is used clinically for osteoarthritis and pain, and in addition the results described here suggest that Vioxx may be useful as a chemopreventive in humans at risk for colorectal neoplasia.

Animals↗
PubMed1986

[Endorectal mucosectomy, endorectal ileal pull-through and ileoanal anastomosis].

Ileoanal anastomosis has evolved as a true alternative to proctocolectomy with permanent ileostomy over the past decade and has made a major impact on the operative treatment of patients with ulcerative colitis and familial polyposis. Experimental studies and clinical experience support the addition of a proximal ileal reservoir to the ileoanal anastomosis. Several types of reservoirs have been proposed of which the U-shaped reservoir has found the widest acceptance and the most frequent application. This reservoir constitutes an adequate replacement for the rectum by providing a low-pressure, compliant, peristaltically quiescent reservoir which still can be triggered to evacuate spontaneously at a reasonable threshold volume. Overall, the ileoanal anastomosis with proximal ileal reservoir fulfills the set clinical requirements: the underlying disease (polyposis, ulcerative colitis) is dealt with in a curative manner. An ileostomy is avoided. Anal continence is preserved. The operative procedure is safe and of comparable mortality and morbidity to the proctocolectomy with ileostomy. It is reasonable to expect that this procedure, i. e. ileoanal anastomosis with proximal ileal reservoir, will become the operation of choice for patients with ulcerative colitis and familial polyposis.

Colectomy↗
PubMedDate not supplied

[The possibility of performing reconstructive-restorative operations in patients with a permanent ileostomy].

An analysis of 69 patients after colectomy with abdomino-anal resection of the rectum for diffuse polyposis was made for the estimation of possibilities to carry out reconstructive-restorative operations with the creation of pelvic small intestine reservoirs. The indications and contraindications for performing such reconstructive operations, main criteria were determined which allowed to estimate the possibility of performing surgical interventions on patients with permanent ileostomy. The significance of each of the criteria is shown for solution of the question of possible performing reconstructive-restorative operations with the formation of pelvic intestinal reservoirs after the previously performed resection of the colon.

Adult↗
PubMed1994

Ganglioneuromas of the gastrointestinal tract. Relation to Von Recklinghausen disease and other multiple tumor syndromes.

We studied 43 patients with ganglioneuromas of the gastrointestinal tract accessioned at the Armed Forces Institute of Pathology (AFIP) from 1940 to 1990 in order to determine their relation to von Recklinghausen's disease and other multiple tumor syndromes. They fell into three groups: polypoid ganglioneuroma (28 patients); ganglioneuromatous polyposis (7 patients); and diffuse ganglioneuromatosis (8 patients). Follow-up (1-24 years, average 8 years) for 16 of 28 patients with polypoid ganglioneuroma showed that none of these patients developed von Recklinghausen's disease or evidence or multiple tumor syndromes. Three of seven patients with ganglioneuromatous polyposis were alive and well but were reported to have multiple cutaneous lipomas and one reported a family history of multiple intestinal polyps. For seven of eight patients, diffuse ganglioneuromatosis was associated with other tumors, namely multiple endocrine neoplasia type IIb, multiple ganglioneuromas and neurofibromas limited to the gastrointestinal tract, von Recklinghausen's disease and neurogenic sarcoma. We conclude that the solitary polypoid ganglioneuroma of the gastrointestinal tract is not associated with the subsequent development of von Recklinghausen's disease or multiple endocrine neoplasia. All three forms of gastrointestinal ganglioneuromatous disease appear to be largely centered in the colon and rectum, unlike neurofibromas and neurofibromatosis, which, in our experience, occur more commonly in the small intestine and stomach.

Adult↗
PubMed1994

Genetic rearrangements in sporadic and familial gastric carcinomas detected with microsatellite markers.

Ten gastric carcinomas were studied for loss of heterozygosity by analysis of 21 microsatellite markers from 14 different chromosomes. Four patients had a family history of gastro-intestinal cancer, and six tumours were considered sporadic. We also studied a new mechanism in tumourigenesis recently reported in hereditary non polyposis colon cancer, a defect in mismatch repair that is seen as gain of new bands by the use of dinucleotide repeat markers. Loss of heterozygosity was detected with two markers in one primary tumour and with the majority of markers in one metastasis from a sporadic gastric tumour. Gain of microsatellite bands was seen in one tumour from a gene carrier in a family with hereditary non-polyposis colon cancer and in one sporadic tumour. Two tumours from patients with a family history of gastric cancer showed no rearrangements. Our results suggest that different types of genes are involved in initiation and progression of gastric cancer in sporadic and familial gastric cancer.

Adult↗
PubMed1997

APC mutation and the crypt cycle in murine and human intestine.

Dysplastic colon adenomas are thought to arise from growth of clones of APC -/- colonic epithelial cells. Isolated clusters of dysplastic crypts are often observed in patients with familial adenomatous polyposis. These patients have genotype APC +/-, and the clusters of dysplastic crypts (called microadenoma or aberrant crypt foci) are thought to represent an early stage in the expansion of a mutant clone of APC -/- cells. It is thought that the growth of these clusters of mutant crypts results from crypt replication through a process similar to what occurs in the normal crypt cycle. We measured the relative replication rate of mutant crypts by analyzing the size of clusters of mutant crypts in APC +/- individuals and found that mutant APC -/- crypts replicate more rapidly than do normal APC +/- (i.e., nonneoplastic) crypts. In contrast, the replication rate of mutant crypts in Apc +/- mice is not significantly different from that of normal crypts, thus supporting previous findings that aberrant crypt foci do not contribute significantly to the colon adenoma population in adult Apc +/- mice. Intriguingly, we found an effect of Apc heterozygosity on the frequency of branching crypts in young mice.

Adenomatous Polyposis Coli↗
PubMed2006

Mutations and nuclear accumulation of beta-catenin correlate with intestinal phenotypic expression in human gastric cancer.

AIMS: Abnormal localization of beta-catenin is frequently observed in human gastric cancers. The aim of the present study was to evaluate relationships among gastrointestinal differentiation phenotypes, beta-catenin localization and mutations of Wnt signalling genes. METHODS AND RESULTS: Seventy-seven regions in 39 gastric adenocarcinomas were classified according to beta-catenin localization and gastric and intestinal phenotypes. Cases with membranous beta-catenin localization showed a gradual decrease from gastric (G) (55% = 6/11) and gastric-and-intestinal-mixed (GI) (17% = 5/29) to intestinal (I) (0% = 0/21) phenotypes, while those with nuclear localization showed a concomitant increase: 18% (2/11), 41% (12/29), 95% (20/21) and 63% (10/16) for G, GI, I and null type (N), respectively (P < 0.001, membranous versus nuclear localization in G, GI through I). Mutations in exon 3 of the beta-catenin gene were found in G (50% = 1/2), GI (67% = 8/12), I (45% = 9/20) and N (0% = 0/10) regions with nuclear beta-catenin localization (GI versus N, P < 0.01; I versus N, P < 0.05). Adenomatous polyposis coli (APC) gene mutations were demonstrated only in GI, I and N types, irrespective of beta-catenin localization. Molecular analysis of these genes revealed 10 tumours to be heterogeneous out of 16 informative cases (62.5%). CONCLUSION: Intestinal phenotypic expression is accompanied by a shift from membranous to cytoplasmic/nuclear accumulation of beta-catenin. In contrast, N-type regions may progress along a different pathway.

Adenocarcinoma↗
PubMed2002

[Endometriosis of the transverse colon--a rare localization].

HISTORY: A 65-year-old woman with no complaints came to our hospital for a colonoscopy because of a family history of a colorectal carcinoma. Because of postmenopausal complaints she had been undergoing estrogen therapy for the past five years. INVESTIGATIONS: Colonoscopy revealed a 2 x 2 cm polyp like structure with central tissue proliferation in the transverse colon. Neither chromoendoscopy with indigocarmine nor multiple biopsies indicated an adenomatous glandular proliferation. Miniendosonography revealed the image of a tumour located in the muscularis propria. DIAGNOSIS AND CLINICAL COURSE: As a malign process could not definitely be excluded, a colon segment resection was carried out by laparoscopy. In the operative specimen there was a 2 x 2 cm large tumour growing under the mucosa. Histologically it was an intramural manifestation of an extragenital endometriosis in the area of the muscularis propria with resulting nodular proliferation of the local muscle system. The ectopic endometrial glands in the area of the endometriosis revealed a complex hyperplasia without atypical features, an image suggesting oestrogen stimulation. CONCLUSION: In many cases the diagnosis of an intestinal endometriosis can not be made through a non-invasive diagnostic method such as colonoscopy with biopsy because of the intramural localisation in the muscularis propria. In order to safely rule out a malignant lesion, in unclear cases a resection should be aimed at.

Adenomatous Polyposis Coli↗
PubMed2002

Detection of dysplastic intestinal adenomas using enzyme-sensing molecular beacons in mice.

BACKGROUND & AIMS: Proteases play key roles in the pathogenesis of tumor growth and invasion. This study assesses the expression of cathepsin B in dysplastic adenomatous polyps. METHODS: Aged Apc(Min/+) mice served as an experimental model for familial adenomatous polyposis. The 4 experimental groups consisted of (a) animals injected with a novel activatable, cathepsin B sensing near infrared fluorescence (NIRF) imaging probe; (b) animals injected with a nonspecific NIRF; (c) uninjected control animals; and (d) non-APC(Min/+) mice injected with the cathepsin B probe. Lesions were analyzed by immunohistochemistry, Western blotting, reverse transcription-polymerase chain reaction, and optical imaging. RESULTS: Cathepsin B was consistently overexpressed in adenomatous polyps. When mice were injected intravenously with the cathepsin reporter probe, intestinal adenomas became highly fluorescent indicative of high cathepsin B enzyme activity. Even microscopic adenomas were readily detectable by fluorescence, but not light, imaging. The smallest lesion detectable measured 50 microm in diameter. Adenomas in the indocyanine green and/or noninjected group were only barely detectable above the background. CONCLUSIONS: The current experimental study shows that cathepsin B is up-regulated in a mouse model of adenomatous polyposis. Cathepsin B activity can be used as a biomarker to readily identify such lesions, particularly when contrasted against normal adjacent mucosa. This detection technology can be adapted to endoscopy or tomographic optical imaging methods for screening of suspicious lesions and potentially for molecular profiling in vivo.

Adenomatous Polyps↗
PubMed1994

Hereditary hemorrhagic telangiectasia associated with multiple pulmonary arteriovenous malformations and juvenile polyposis.

A case with multiple telangiectases of the gastrointestinal tract that caused recurrent bleeding is reported. The hemorrhagic telangiectases were associated with multiple pulmonary arteriovenous malformations leading to significant right-to-left shunting and in combination with an atrial septal defect to progressive right heart failure and finally to the death of the patient. Juvenile polyps and tubulovillous adenomas of the colon were removed. Hemicolectomy had to be performed because of carcinomatous infiltration originating from adenomatous epithelium developing in a juvenile polyp. The pathogenesis of hemorrhagic telangiectases is unknown. It is an important source of intestinal hemorrhage and may be complicated by the additional finding of arteriovenous fistulas and the occurrence of recurrent juvenile, adenomatous epithelium containing colonic polyps eventually leading to carcinoma. The present case suggests an inherited association of hemorrhagic telangiectases and juvenile polyposis. It also highlights that rapidly progressive right-to-left shunting rather than hemorrhagic anemia my be the major determinant of the course of the disease.

Adenomatous Polyposis Coli↗
PubMed2007

Mesenteric desmoid tumors in Singapore familial adenomatous polyposis patients: clinical course and genetic profile in a predominantly Chinese population.

PURPOSE: This study examined the mutational profile of the adenomatous polyposis coli gene in relation to the development of desmoid tumors in familial adenomatous polyposis patients from a predominantly Chinese population. METHODS: This is a retrospective review of all patients with familial adenomatous polyposis coli from the Singapore Polyposis Registry. Identification of specific adenomatous polyposis coli gene mutation was performed and clinical course of associated desmoid disease obtained from case records and a computerized database. RESULTS: Two hundred five patients from 75 families afflicted with familial adenomatous polyposis coli were reviewed, with gene mutations identified in 107 patients. Of these, 23 (11.2 percent) developed desmoids. The male-to-female ratio was 1:1.3 and the ethnic distribution was Chinese (n=17) and Malay (n=6). Of the 92 patients with mutations 5' to codon 1444, 11 patients (12 percent) developed desmoids compared with 6 of 15 (40 percent) patients with adenomatous polyposis coli gene mutations 3' to codon 1444 (P<0.01). The clinical course of desmoid tumors can be divided into stable (n=11), variable (n=3), progressive (n=6), and aggressive growth (n=3). Only 3 (13 percent) patients with aggressive tumor growth required chemotherapy. There was no correlation between the site of mutation and the clinical progression of the desmoids. Seventy-four percent of these desmoids (17/23) developed at a mean interval of 2.98 years after restorative proctocolectomy, while only 30 percent (7/23) were diagnosed preoperatively or discovered during the initial surgery. The most common complications related to the mesenteric desmoids were intestinal obstruction (21.7 percent), ureteric obstruction (17.4 percent), and encasement of superior mesenteric vessels (13 percent). CONCLUSION: The clinical course of desmoids in an individual familial adenomatous polyposis patient remains unpredictable and no reliable genetic marker is available for prognostication in desmoid disease.

Adenomatous Polyposis Coli↗