Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0033036 (APC)
 10,214 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Familial adenomatous polyposis (FAP) is a common hereditary syndrome characterized by early development of colorectal cancer consequent to extensive adenomatous polyps of the colon. In addition to the colonic manifestations the syndrome presents several extracolonic features including polyps of the upper gastrointestinal tract, congenital hypertrophy of the retinal pigment, jaw cysts, osteomata and desmoid tumors. In this study the entire APC coding region has been analysed for mutation in a panel of one Turcot and 33 unrelated Italian FAP patients using SSCP analysis, PTT and DNA sequencing. We detected APC mutations in 23 of them and identified nine which, to our knowledge were not previously reported. All of these novel mutations are in exon 15, including two nonsense mutations, 6 deletions or insertions leading to premature termination of the protein and one missense mutation (7697G>A). This last mutation occurs in the EB1-binding domain of the APC protein and segregates in four relatives of the patient with three of them presenting 2-3 adenomatous polyps.
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PMID:Nine novel APC mutations in Italian FAP patients. 1131 65

The immunohistochemical expression of beta-catenin, cyclin D1, Ki-67 and PCNA was Examined in 38 cases of sporadic extra-abdominal or abdominal-wall desmoid tumours without familial adenomatous polyposis (FAP), to evaluate the hypothesis that the accumulated beta-catenin within the nuclei could affect the regulation of the cyclin D1 gene. There was a statistically significant correlation between beta-catenin accumulation and cyclin D1 overexpression (p=0.029). Each group with beta-catenin accumulation or cyclin D1 overexpression showed a higher PCNA-LI than those without, the difference being statistically significant (p=0.007, p=0.004, respectively). Differential PCR was also performed to detect amplification of the cyclin D1 gene and mutational analysis was undertaken for exon 3 of the beta-catenin gene. Amplification of the cyclin D1 gene was observed in 13 out of 22 cases (59.1%). There were nine-point mutations in 7 out of 18 cases (38.9%). The distribution of beta-catenin mutation fell within a wide range, from codon 21 to codon 67. In conclusion, beta-catenin nuclear expression correlated with cyclin D1 overexpression in sporadic desmoid tumours, which could be an in vivo model system for the APC-beta-catenin-Tcf pathway. In addition, beta-catenin mutations in desmoid tumours occurred at an unusually wide range of sites within the gene.
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PMID:beta-catenin nuclear expression correlates with cyclin D1 overexpression in sporadic desmoid tumours. 1159 2

Desmoids are rare tumors of the connective tissue. It develops about 1:1000 times more in patients with familial adenomatous polyposis (FAP, Gardner syndrome) compared to normal population. It has been shown in molecular genetic examinations, that different mutations of the APC gene are responsible for desmoid tumors in FAP. It means, that this disease is one of the extraintestinal manifestations of Gardner syndrome. This tumor has high recurrence rate and is growing rapidly, and as a result it is the second most common cause of death in FAP patients. That is why genetic examination for FAP patients is advised to decide if the patient has higher risk for desmoid formation. If the result of the genetic test is positive, it is advisable to try to slow the progression of polyposis with medical treatment, and so to delay the date of the colectomy because the surgical intervention--and connective tissue damage--can induce desmoid formation in these patients. At the same time it is reasonable to examine and regularly control patients with sporadic desmoid tumors searching for other manifestations of Gardner syndrome (colon, stomach and duodenum polyposis, tumor of papilla Vateri, retinopathy, etc.). Palliative surgery is not indicated in patients with inoperable intraabdominal desmoid tumors, because partial resections (R1, R2, debulking) result in further tumor progression. In these patients medical treatment (sulindac, tamoxifen), chemotherapy (doxorubicin, dacarbazin) and radiotherapy or combination of them can result tumor remission. We describe our three patients (an abdominal wall desmoid four years following Cesarean section; a desmoid tumor in the retroperitoneum and in the pelvis diagnosed three years after total colectomy; and a retroperitoneal and abdominal wall desmoid one year after total colectomy) and etiology, diagnosis and therapy of desmoid tumors are discussed.
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PMID:[Desmoid tumors in three patients]. 1181 39

Fibromatoses of the breast are nonmetastasizing tumors, but can be infiltrative and locally recurrent. Breast fibromatoses are rare, and their specific genetic alterations have not been elucidated. However, their occasional occurrence in patients with familial adenomatous polyposis (FAP) and their morphologic identification with other deep fibromatoses (desmoid tumors) suggest that alterations of the APC/beta-catenin pathway might be involved in the pathogenesis of sporadic and FAP-associated breast fibromatoses. We analyzed somatic beta-catenin and APC gene mutations in 33 breast fibromatoses (32 sporadic and 1 FAP-associated) using immunohistochemistry for beta-catenin, 5q allelic loss assays, and direct DNA sequencing for exon 3 of the beta-catenin gene and the mutation cluster region of the APC gene. Nuclear accumulation of beta-catenin was present in the stromal tumor cells in most (82%) cases but not in normal stroma or mammary epithelial cells. Somatic alterations of the APC/beta-catenin pathway were detected in 79% of breast fibromatoses, including activating beta-catenin gene mutations in 15 cases and somatic APC alterations (mutation or 5q allelic loss or both) in 11. These findings indicate that alterations of the APC/beta-catenin pathway with resultant nuclear translocation of beta-catenin are important in the pathogenesis of both sporadic and FAP-associated breast fibromatosis. The spectrum of beta-catenin and APC alterations is similar to that described for desmoid tumors of the abdomen, paraspinal region, and extremities.
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PMID:Fibromatosis of the breast and mutations involving the APC/beta-catenin pathway. 1182 72

Reports on the association of papillary thyroid carcinoma with paraganglionic or desmoid tumors have appeared infrequently. The former setting usually affects middle-aged females; the latter is typical of familial adenomatous polyposis. We report the case of a 69-yr-old man in whom two abdominal masses had been instrumentally detected following an access of abdominal pain. Save for a moderate hypertension, he was asymptomatic and an impalpable thyroid nodule was detected by ultrasonography. A high urinary noradrenaline output and cytology of the masses raised the suspicion of pheochromocytoma. At laparotomy, an adrenal pheochromocytoma and a paracaval paraganglioma were excised. Subsequently, hemithyroidectomy was performed, and histopathology revealed papillary microcarcinoma. A nodule of desmoid tumor was also removed from the abdominal wall. An analysis of RET, APC, and TP53 gene mutations, and of RET and NTRK1 gene rearrangements, yielded negative results. No in vitro transforming activity was detected in the tumor DNA when assayed in transfection experiments. The lack of a consistent family history also made unlikely the possibility of identifying the putative germline defect by linkage analyses. Should this unusual aggregation of tumors represent a new entity, a number of genetic alterations have now been excluded.
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PMID:Concurrent Pheochromocytoma, Paraganglioma, Papillary Thyroid Carcinoma, and Desmoid Tumor: A Case Report with Analyses at the Molecular Level. 1211 65

Desmoid tumours (DT) are slow-growing tumours that consist of proliferations of well-differentiated fibroblasts. Although the typical characteristics of malignant tumours, such as distant metastases, are absent, the tumours are locally aggressive and grow into neighbouring structures. The prevalence of desmoid tumours in patients with FAP is 7-12%. The lifetime risk of developing desmoid tumours is about 20%. In FAP, most tumours are intra-abdominal or located in the abdominal wall. Next to colorectal cancer, desmoid tumours are the most frequent cause of death in FAP. Possible risk factors for the development of desmoid tumours are previous surgical procedures, pregnancy, female sex, a family history of desmoid tumours, and specific mutations in the APC-gene. Both CT scanning and MRI can be used to detect the tumours. An excision biopsy is needed to establish the diagnosis. Medicinal treatment with NSAIDs is the treatment of first choice, followed by hormonal treatment (e.g., tamoxifen) in combination with NSAIDs. Both forms of treatment lead to a response in about 30-50% of the patients. Surgery is the preferred treatment for extra-abdominal tumours or tumours located in the abdominal wall. Surgical treatment of intra-abdominal tumours is only indicated in patients with obstruction of the bowel or ureter. Chemotherapy is indicated in patients with progressive desmoid tumours when non-cytotoxic treatment has failed. Radiotherapy may play a role in the treatment of irresectable extra-abdominal or abdominal wall tumours, or as adjuvant treatment of tumours with positive margins.
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PMID:[Desmoid tumors in patients with familial adenomatous polyposis]. 1216 72

Familial adenomatous polyposis predisposes to colorectal cancer through multiple colorectal adenomas. The age of onset of adenomas and their number vary between families affected by this dominantly inherited trait, even within families. The same applies to a variety of associated manifestations including epidermoid cysts, osteomas, dental anomalies, desmoid tumours, retinal pigmentation and upper gastrointestinal polyps. The phenotype variation has a relationship with the site of truncating mutations on the APC gene. Thus, mutations at the mutation cluster region (codons 1250-1400) tend to cause early onset and severe polyposis whereas osteomas, dental changes and desmoids are most frequent in patients with the mutation 3' to codon 1400. The correlation observed, however, seems quite complex. Explanations may include variable interference of different mutant APC proteins on the wildtype APC function. There is also evidence suggesting an effect of modifier genes. The clinical applications of genotype-phenotype correlation on the management of patients with familial adenomatous polyposis remain limited apart from predictive genetic testing.
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PMID:The complex genotype-phenotype relationship in familial adenomatous polyposis. 1509 46

Familial adenomatous polyposis (FAP) is an autosomal dominant, hereditary colon cancer syndrome that is characterized by the presence of innumerable adenomatous polyps in the colon and rectum. Gardner's syndrome is a variant of FAP, which in addition to the colonic polyps, also presents extracolonic manifestations, including desmoid tumors, osteomas, epidermoid cysts, various soft tissue tumors, and a predisposition to thyroid and periampullary cancers. Mutations of the APC gene are thought to be responsible for the development of FAP, and the location of the mutation on the gene is thought to influence the nature of the extracolonic manifestations that a given patient might develop. Though patients are often asymptomatic, bleeding, diarrhea, abdominal pain and mucous discharge frequently occur. Diagnostic tools include genetic testing, endoscopy, and monitoring for extra-intestinal manifestations. Currently, surgery is the only effective means of preventing progression to colorectal carcinoma. Restorative proctocolectomy with ileal pouch anal anastomosis (RPC/IPAA) with mucosectomy is the preferred surgical procedure, since it attempts to eliminate all colorectal mucosa without the need for an ostomy. Periampullary carcinoma and intra-abdominal desmoid tumors are a significant cause of morbidity and mortality in these patients after colectomy. Frequent endoscopy is needed to prevent the former, while there is no definitive treatment available yet for the latter. The following article presents a case and reviews the evaluation, management and treatment of Gardner's syndrome.
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PMID:Familial polyposis coli: clinical manifestations, evaluation, management and treatment. 1559 57

Desmoid tumors are fibromatous lesions occurring both sporadically and in patients with familial adenomatous polyposis (FAP). Because of the association of these tumors with the hereditary colorectal cancer syndrome FAP we set out to define the molecular events driving desmoid tumorigenesis, hypothezising these might be identical to events driving colorectal tumorigenesis. We found that whereas FAP-associated desmoid tumors are caused by germline APC mutations followed by somatic inactivation of the wild-type APC allele, sporadic desmoids are usually characterized by oncogenic mutations in the b-catenin gene, both identical molecular alterations to those found in the vast majority of colorectal cancers. Next we set out to investigate the cellular pathways activated by these mutations, and identified activation of the Wnt signaling pathway in desmoid tumors. Wnt signaling modulates expression of developmental genes and cell fate via beta-catenin, and has been implicated in many cancer types. Currently we are investigating tissue-specific downstream effectors of the Wnt pathway that might be responsible for the behaviour of these invasive fibrous tumors. Our findings also point to a role for this pathway in the regulation of normal myofibroblast proliferation and suggest novel treatments in desmoid tumors and other fibrous proliferative disorders.
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PMID:Analysis of Wnt/Beta catenin signalling in desmoid tumors. 1583 80

Heterozygous germline DNA mismatch repair gene mutations are typically associated with HNPCC. Here we report the case of a proband whose father was known for familial adenomatous polyposis. The number of polyps (less than ten) was not typical of polyposis; therefore, the diagnosis of HNPCC was entertained. Microsatellite instability analyses were performed on peripheral blood and biopsy of a right-sided dysplastic adenoma. The tumour tissue showed high-grade instability, and subsequently, immunohistochemistry showed that neither MSH2 nor MSH6 proteins were expressed in tumour cells. Prophylactic colectomy was performed, and an adenocarcinoma developing within the adenoma was diagnosed (pT1N0). Genomic DNA analysis revealed a novel mutation in MSH2 as a frameshift mutation in exon 7 (c.1,191_1,192dupG). Both parents of the proband were analyzed for MSH2 and APC mutations, and in the father, a truncating mutation in exon 15 of APC was identified as del3471-3473GAGA. This mutation was found to be present in the proband. His mother was found to bear the MSH2 exon 7 mutation. At follow-up, the proband was diagnosed with fundic, antral and duodenal adenomas (one fundic adenoma showed low-grade dysplasia). Several tubular rectal adenomas with low-grade dysplasia were excised. The patient later developed an intra-abdominal desmoid tumour.
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PMID:Double frameshift mutations in APC and MSH2 in the same individual. 1667 98


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