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Hamartomatous polyps of the colon: ganglioneuromatous, stromal, and lipomatous.

Intestinal ganglioneuromas comprise benign, hamartomatous polyps characterized by an overgrowth of nerve ganglion cells, nerve fibers, and supporting cells in the gastrointestinal tract. This polyposis has been divided into 3 subgroups, each with a different degree of ganglioneuroma formation: polypoid ganglioneuroma, ganglioneuromatous polyposis, and diffuse ganglioneuromatosis. The ganglioneuromatous polyposis subgroup is not known to coexist with systemic disorders that often have an associated intestinal polyposis, such as multiple endocrine neoplasia type IIb, neurofibromatosis type I, and Cowden syndrome. We report a case of ganglioneuromatous polyposis plus cutaneous lipomatosis in a 41-year-old man with no established systemic disease. However, he possessed unique anatomic findings in addition to his ganglioneuromatosis, suggesting that the ganglioneuromatosis-lipomatosis in our patient may represent an unrecognized syndrome. This case report and brief review of the literature provide an overview of intestinal ganglioneuromatosis in relation to the hereditary polyposis syndromes and describe the individual ganglioneuromatosis subgroups.

Adult↗

Familial juvenile adenomatous polyposis.

Most colonic polyps in children are of the juvenile type and occur either as single or scattered colonic polyps. The peak incidence occurs between 4 and 6 yr of age, with a spontaneous decline from 12 to 15 yr. Significant clinical symptoms are rare, and operative therapy is rarely indicated. Diffuse colonic juvenile polyposis, however, varies with different clinical, prognostic, and genetic implications. In infancy, colonic polyposis may be associated with diffuse gastrointestinal involvement leading to fatal complications unless treated aggressively. In childhood, colonic polyposis can occur with a genetic variance with an increased incidence of familial intestinal malignancies. Colonic polyposis in childhood, both familial and nonfamilial, can present with a mixed form of juvenile and adenomatous polyposis. In children with colonic polyposis, the biopsy of a single polyp that reveals the histologic appearance of a juvenile polyp does not rule out the simultaneous existence of adenomatous polyps.

Adolescent↗

[Dysbacteriosis in patients with colon polyposis].

The study revealed the most profound changes in the composition of intestinal microflora in patients with polyposis of the large intestine. In these patients anaerobic microflora (bifidobacteria, lactic acid bacteria) was more often suppressed than in other examined groups, in particular, patients with cholelithic disease. The associations of hemolytic Escherichia with Klebsiella pneumoniae, Pseudomonas aeruginosa, Citrobacter freundii were often observed as well as the increased content of enterococci and fungi of the genus Candida. The determination of frequency and degree of manifestations showed that dysbacteriosis was registered in the absolute majority of patients (97.4%) with polyposis of the large intestine. Among patients with cholelithic disease disturbances in microbiocenosis were detected in 60.0% of cases, the profundity and character of the microflora composition changes being less pronounced.

Bifidobacterium↗

Adenomatous polyposis coli control of retinoic acid biosynthesis is critical for zebrafish intestinal development and differentiation.

Mutations in the APC (adenomatous polyposis coli) tumor suppressor gene cause uncontrolled proliferation and impaired differentiation of intestinal epithelial cells. Recent studies indicate that human colon adenomas and carcinomas lack retinol dehydrogenases (RDHs) and that APC regulates the expression of human RDHL. These data suggest a model wherein APC controls enterocyte differentiation by controlling retinoic acid production. However, the importance of APC and retinoic acid in mediating control of normal enterocyte development and differentiation remains unclear. To examine the relationship between APC and retinoic acid biosynthesis in normal enterocytes, we have identified two novel zebrafish retinol dehydrogenases, termed zRDHA and zRDHB, that show strong expression within the gut of developing zebrafish embryos. Morpholino knockdown of either APC or zRDHB in zebrafish embryos resulted in defects in structures known to require retinoic acid. These defects included cardiac abnormalities, pericardial edema, failed jaw and pectoral fin development, and the absence of differentiated endocrine and exocrine pancreas. In addition, APC or zRDHB morphant fish developed intestines that lacked columnar epithelial cells and failed to express the differentiation marker intestinal fatty acid-binding protein. Treatment of either APC or zRDHB morphant embryos with retinoic acid rescued the defective phenotypes. Downstream of retinoic acid production, we identified hoxc8 as a retinoic acid-induced gene that, when ectopically expressed, rescued phenotypes of APC- and zRDHB-deficient zebrafish. Our data establish a genetic link supporting a critical role for retinoic acid downstream of APC and confirm the importance of retinoic acid in enterocyte differentiation.

Adenomatous Polyposis Coli Protein↗

Adenomatous polyposis coli truncation alters cytoskeletal structure and microtubule stability in early intestinal tumorigenesis.

Partial loss of function of adenomatous polyposis coli (APC) protein by truncation of its carboxy (C)-terminus is an early factor in the development of many sporadic colorectal cancers. In the C57BL/6J Min/+ (Min/+) mouse, an animal with a germline mutation of Apc, we found that APC truncation was associated with reduced enterocyte migration and loss of association and membrane expression of adherens junction proteins. We hypothesized that these defects were related to changes in cytoskeletal function resulting from truncation of the APC C-terminus, which contains microtubule binding regions, as well as putative sites for indirect actin binding. We investigated this further by determining whether APC truncation produced in vivo changes in actin cytoskeletal structure and microtubule stability. The actin cytoskeleton of histologically normal enterocytes from Min/+ mice was compared to that of Apc+/+ (wild-type) mice by confocal indirect immunofluorescence microscopy. We found a significant loss of actin localization at the apical plasma membrane in Min/+ enterocytes. In addition, immunoblotting revealed increased levels of both unstable Tyr-tubulin and alpha-tubulin turnover in Min/+ enterocytes, indicating an alteration in microtubule dynamics. These studies suggest that loss of actin localization and changes in microtubule dynamics may be dominant negative effects of truncated APC. These changes are consistent with the defects in enterocyte migration and junctional complex formation observed in the Min/+ model of early APC-associated colorectal tumorigenesis.

Adenomatous Polyposis Coli↗

Suppression of intestinal polyp development by low-fat and high-fiber diet in Apc(delta716) knockout mice.

Most epidemiological and animal studies show a positive correlation of the dietary intake of fat with the incidence of colon cancer, whereas an inverse correlation of the dietary intake of fiber. In rats fed a diet low in fat and high in wheat bran fiber and calcium, a significant decrease was reported in the number of azoxymethane-induced aberrant crypt foci compared with those fed a high-fat, low-fiber and low-calcium diet. Mutations in the human APC gene play a key role, not only in familial adenomatous polyposis, but also in many sporadic cancers of the entire digestive tract. We previously constructed a mouse strain Apc(delta716), carrying a truncation mutation at codon 716 of the Apc gene, the homolog of human APC (10). The heterozygous mice developed numerous intestinal polyps, and all microadenomas dissected from the earliest polyps had already lost the wild-type allele, indicating the loss of heterozygosity. Using these Apc(delta716) knockout mice, we have investigated the effect of a low-fat and high-fiber diet (LRD for 'low-risk' diet) on intestinal polyposis, and compared it with that of a high-fat and low-fiber diet (HRD for 'high-risk' diet). The mice were fed either diet for 7 weeks, and the number and size of intestinal polyps were scored. The LRD-fed mice had fewer polyps than the HRD-fed mice, by 36% in the small intestine and by 64% in the colon. As for the polyp size distribution, there was no significant difference between the HRD- and LRD-fed mice. These results indicate that LRD can suppress intestinal polyposis compared with HRD which does not, and suggest that its suppression is at the initiation of polyp formation. This is likely to be due to a decreased frequency of loss of heterozygosity, rather than a retarded growth of the polyp adenomas.

Animals↗

Inactivation of both APC alleles in human and mouse tumors.

Germline mutations of the adenomatous polyposis coli (APC) gene lead to multiple intestinal tumors in familial adenomatous polyposis patients and in multiple intestinal neoplasia (Min) mice. Current models predict that inactivation of the remaining normal allele of a tumor suppressor gene is rate limiting for tumor formation, but this has been difficult to prove. While examination of colorectal adenomas from familial adenomatous polyposis patients identified somatic inactivating mutations of the second allele in the majority of tumors (19 of 24), the absolute requirement for an early inactivating event could not be demonstrated. In contrast, inactivation of the remaining allele of the murine APC (Apc) could be demonstrated in 100% (30 of 30) of tumors from Min mice. Moreover, inactivation was observed in the earliest recognizable phase of tumors, including some lesions containing as few as two dysplastic crypts. These results suggest that the mutation of the second APC allele is an early event in Min and familial adenomatous polyposis tumorigenesis, supporting Knudson's hypothesis.

Adenomatous Polyposis Coli↗

In utero and neonatal sensitivity of ApcMin/+ mice to radiation-induced intestinal neoplasia.

PURPOSE: To assess the sensitivity of ApcMin/+ mice (adenomatous polyposis coli Apc, multiple intestinal neoplasia, Min) to the development of intestinal adenomas after x-irradiation in utero, as neonates, or as young adults. MATERIALS AND METHODS: CHB6 ApcMin/+ mice were exposed to an acute dose of 2 Gy x-rays either in utero on day 7 or 14 post-conception, as 2-day or 10-day neonates or as 35-day young adults. Tumour identification and counting was performed 200-214 days later. RESULTS: Irradiation as 10-day-old neonates resulted in a significantly greater overall tumour incidence (average of about 130 tumours per animal) than irradiation as 35-day-old young adults (about 70 tumours). Irradiation as 2-day-old neonates resulted in an intermediate incidence (about 85 tumours). In contrast, the greatest tumour incidence observed after in utero irradiation of ApcMin/+ mice, of about 44 tumours per animal after 2 Gy irradiation at 14 days post-conception, was significantly lower than the incidence in irradiated adults. Tumour incidences after irradiation as 7-day embryos was not significantly raised above numbers in unirradiated controls (about 30 tumours). These tumour numbers include cystic crypts, largely radiation-induced, which were classed as early stage microadenomas on the basis of loss of wild-type Apc+ and expression of beta-catenin. CONCLUSIONS: The sensitivity of ApcMin/+ mice to the induction of intestinal tumours by radiation was shown to be in the order: 10 d neonates>2 d neonates>35 d young adults>14 d fetus>7 d embryo.

Age Factors↗

Adenomatous polyposis coli control of C-terminal binding protein-1 stability regulates expression of intestinal retinol dehydrogenases.

Mutations in the human adenomatous polyposis coli (APC) gene are thought to initiate colorectal tumorigenesis. The tumor suppressor function of APC is attributed primarily to its ability to regulate the WNT pathway by targeting the destruction of beta-catenin. We report here a novel role for APC in regulating degradation of the transcriptional co-repressor C-terminal-binding protein-1 (CtBP1) through a proteasome-dependent process. Further, CtBP1 suppresses the expression of intestinal retinol dehydrogenases, which are required for retinoic acid production and intestinal differentiation. In support of a role for CtBP1 in initiation of colorectal cancer, adenomas taken from individuals with familial adenomatous polyposis contain high levels of CtBP1 protein in comparison with matched, uninvolved tissue. The relationship between APC and CtBP1 is conserved between humans and zebrafish and provides a mechanistic model explaining APC control of intestinal retinoic acid biosynthesis.

Adenoma↗

[Effectiveness of preserving large intestinal segments in surgical treatment of proliferative diffuse polyposis].

Among 390 patients who were operated on in the Research Institute of Proctology for the proliferative form of diffuse polyposis, 242 underwent various types of operations in which polyp-free segments of the large intestine were not resected. In the first 5 postoperative years all 242 patients were examined, in follow-up periods of 6 to 10 years 144 patients (59.5%), in periods of 11 to 15 years 88 patients (36.4%), in periods of 16 to 20 years 28 patients (11.6%), and after 21 years 8 patients (3.3%) were examined. Development of carcinoma in the preserved segments was encountered in 26 patients (10.7%), and intensive growth of polyps for which the preserved segment had to be removed was found in 5 patients (2.1%). There was no significant increase of the risk of carcinoma development in the preserved intestinal segments in patients who previously had a malignant tumor in the resected part of the large intestine. The development of carcinoma and intensive growth of polyps were encountered most frequently in patients in whom the distal parts of the large intestine were not removed during the operation. The obtained data are evidence of the validity of the choice of the volume of the operation based on the endeavor to preserve the polyp-free parts of the large intestine for rehabilitation of the patients.

Adolescent↗

Comparative study of familial polyposis coli and nonpolyposis coli on the histogenesis of large-intestinal adenoma.

The entire length of the large intestine resected from six patients with familial polyposis coli (FPC) was step-sectioned, and microscopic adenomas composed of one to several glands were prepared into complete serial sections. Histopathologic comparison of these microscopic adenomas was made between FPC and nonpolyposis coli (those not included in the special disease group of FPC). The histogenesis of adenomas in FPC and nonpolyposis coli was considered as follows. (1) In nonpolyposis coli, adenomas arise from basal cells of the deep layer of the mucosa. (2) In FPC, most of the adenomas (81.2 per cent) arise in the same manner as described above, although there are some (18.8 per cent) that appear to have arisen in the middle or superficial layer of the mucosa. (3) Therefore, it is believed that the morphologic difference of the large-intestinal mucosa between FPC and nonpolyposis coli comes not from the difference in the number of adenomas present but from the difference in the position and/or timing of appearance of adenomas.

Adenoma↗

Intestinal trefoil factor controls the expression of the adenomatous polyposis coli-catenin and the E-cadherin-catenin complexes in human colon carcinoma cells.

Intestinal trefoil factor 3 (TFF3) is a member of the trefoil family of peptides, small molecules constitutively expressed in epithelial tissues, including the gastrointestinal tract. TFF3 has been shown to promote migration of intestinal epithelial cells in vitro and to enhance mucosal healing and epithelial restitution in vivo. In this study, we evaluated the effect of recombinant TFF3 (rTFF3) stimulation on the expression and cellular localization of the epithelial (E)-cadherin-catenin complex, a prime mediator of Ca2+ dependent cell-cell adhesion, and the adenomatous polyposis coli (APC)-catenin complex in HT29, HCT116, and SW480 colorectal carcinoma cell lines. Stimulation by rTFF3 (10(-9) M and 10(-8) M) for 20-24 hr led to cell detachment and to a reduction in intercellular adhesion in HT29 and HCT116 cells. In both cell lines, E-cadherin expression was down-regulated. The expression of APC, alpha-catenin and beta-catenin also was decreased in HT29 cells, with a translocation of APC into the nucleus. No change in either cell adhesion or in the expression of E-cadherin, the catenins, and APC was detected in SW480 cells. In addition, TFF3 induced DNA fragmentation and morphological changes characteristic of apoptosis in HT29. Tyrphostin, a competitive inhibitor of protein tyrosine kinases, inhibited the effects of TFF3. Our results indicate that by perturbing the complexes between E-cadherin, beta-catenin, and associated proteins, TFF3 may modulate epithelial cell adhesion, migration, and survival.

Adenomatous Polyposis Coli Protein↗

[Multiple cartilaginous exostoses with polyposis of stomach and colon: a new, hereditary combination different from Gardner's syndrome (author's transl)].

Multiple cartilaginous exostoses were found in a 41-year-old man and his two sons, aged 11 and 15 years. The older boy had extensive polyposis of the sigmoid colon and gastric antrum, his brother had radiological changes suspicious of sigmoid polyposis, while there was no radiological evidence of polyposis in the father. None of them had any symptoms of polyposis. The described combination of findings suggests a separate entity from Gardner's syndrome, perhaps on the basis of a combined dominant gene inheritance. In case of multiple exostoses radiological and endoscopic examination of the gastro-intestinal tract for polyposis are indicated.

Adolescent↗

[The colorectal carcinoma; pathological remarks (author's transl)].

A survey is presented on the incidence of colorectal carcinomas in the GDR, exogenous causes possibly being responsible for the increase in incidence, common screening methods, macro-anatomy and micro-anatomy of colorectal carcinoma, staging, prognosis, and pathways of metastases. The correlation between intestinal polypi and colorectal carcinoma as well as the frequency of their degeneration are also referred to. Adenomatous polypi (polypous adenoma), villous polypi (villous adenoma), and certain rare intestinal polypi, such as familial polyposis coli, multiple polyposis of the entire gastro-intestinal tract, as well as the Gardner- and Turcot-syndromes, are some of those polypi which depending on their size tend to malignant degeneration. Histological information provided by the pathologist is discussed in its value and importance for surgical practice.

Adult↗

Secretory phospholipase Pla2g2a confers resistance to intestinal tumorigenesis.

Individuals inheriting the same mutation predisposing to cancer may show very different outcomes, ranging from early aggressive cancer to disease-free survival. Experimental mouse models can provide a powerful tool to identify factors in the environment and genetic background that account for such modifications. The Min mouse strain, in which the ApcMin mutation disrupts the mouse homologue of the human familial polyposis gene, develops intestinal neoplasms whose multiplicity is strongly affected by genetic background. We previously mapped a strong modifier locus, Mom1 (modifier of Min-1), to a 4-cM region on mouse chromosome 4 containing a candidate gene Pla2g2a encoding a secretory phospholipase. Here, we report that a cosmid transgene overexpressing Pla2g2a caused a reduction in tumour multiplicity and size, comparable to that conferred by a single copy of the resistance allele of Mom1. These results offer strong evidence that this secretory phospholipase can provide active tumour resistance. The association of Pla2g2a with Mom1 thus withstands a strong functional test and is likely to represent the successful identification of a polymorphic quantitative trait locus in mammals.

Adenomatous Polyposis Coli↗