Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.4.11.18 (MAP)
 7,412 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

MAP (MutYH-associated polyposis) is a recently described colorectal adenoma and carcinoma predisposition syndrome that is associated with biallelic-inherited mutations of the human MutY homologue gene, MutYH. MutYH is often also termed MYH. MAP tumours display a mutational signature of somatic guanine-to-thymine transversion mutations in the adenomatous polyposis coli and K-ras genes, reflecting the normal role of MutYH in the base excision repair of adenines misincorporated opposite 7,8-dihydro-8-oxoguanine, a prevalent and stable product of oxidative damage to DNA. However, the full genetic pathway of MAP tumorigenesis has not been elucidated.
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PMID:MutYH (MYH) and colorectal cancer. 1604 73

The management of patients with multiple intestinal polyps may be difficult and greatly depends on the correct classification. Polyposis syndromes account for less than 1% of newly diagnosed colorectal cancers. In addition the risk for extracolonic cancer is increased in most syndromes. Here we report the case of a difficult patient with severe gastric polyposis and we present a review of polyposis syndromes such as classical and attenuated familial adenomatous polyposis (FAP), MYH-associated polyposis, Peutz-Jeghers syndrome, juvenile polyposis as well as rare polyposis syndromes. The most practical approach for the diagnostic workup in patients with newly diagnosed gastrointestinal polyposis is based on the histological typing of polyps. In addition, a detailed family history regarding cancer, polyps and congenital abnormalities should be obtained from every polyposis patient. Patients with multiple adenomas are most likely to suffer from FAP, AFAP or MAP. Of these, younger age and higher polyp count are most likely a diagnosis of typical FAP. Older age and fewer polyps favour a diagnosis of AFAP or MAP. Germline testing of the APC gene is suggested, and if negative, MYH gene testing should be done. In patients with hamartomas, extraintestinal features should be evaluated and reference histology should be initiated. In addition panintestinal imaging should be performed with EGD, colonoscopy and small bowel imaging (PE, CE, and MR) enteroclysis. For diagnostic and therapeutic problems a familial colorectal cancer center should be consulted. Using this algorithm, correct classification and adequate treatment should be possible for every polyposis patient.
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PMID:The patient with multiple intestinal polyps. 1754 8

The colorectal polyposes are uncommon and frequently present diagnostic difficulties. Although the final diagnostic arbiter is the demonstration of a germline mutation, this may not always be demonstrable, and some forms of colorectal polyposis have no known genetic basis. Therefore, an accurate description of the phenotype by the pathologist is central to the establishment of a working diagnosis. This can direct the search for the underlying genetic cause (if any) and is also essential for establishing the magnitude of risk of colorectal malignancy for the patient and the patient's relatives. The pathologist may be provided with only a small and selected sample of endoscopically resected polyps or with prodigious numbers of polyps (too many to sample) when receiving a surgical specimen. Each type of polyposis presents its own particular diagnostic problems that may relate to polyp numbers, gross recognition of small or flat polyps, incomplete development of the full phenotype at the stage of investigation, and the histological classification of unusual or mixed polyps. The aim of this review is to highlight the principles and pitfalls in achieving a comprehensive description of the various types of colorectal polyposis, including classical FAP, attenuated FAP, MUTYH- (formerly MYH-) associated polyposis (MAP), other presentations of multiple adenomas, Peutz-Jeghers syndrome (P-JS), juvenile polyposis syndrome (JPS), Cowden syndrome (CS), hereditary mixed polyposis syndrome (HMPS), and hyperplastic polyposis syndrome (HPS).
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PMID:Colorectal polyposes: from phenotype to diagnosis. 1854 88

The case presented raised our scientific curiosity and it is worthy of being brought in front of the medical audience because of several reasons presented below. Presently, there are 3 hereditary syndromes that have a demonstrated etiological relationship with the colorectal cancer: Familiar Adenomatous Polyposis (FAP syndrome), HNPCC syndrome (Hereditary Nonpoliposis Colorectal Cancer) and MAP syndrome.Discovered only in 2002, the MAP syndrome (MYH associated polyposis) is the first hereditary syndrome that has autosomal recessive transmission. The APC gene can be mutated in several ways during the colonic oncogenesis: congenital in the FAP syndrome, somatic in sporadic colorectal cancers and secondary to the MYH gene inactivation in MAP syndrome. MAP phenotype is similar to the FAP phenotype because of the somatic mutations to the APC gene. Colonic polyposis is lower than FAP syndrome and appeared later, in the 40's and 50's. Colorectal cancers are frequent and discovered in the same moment as the colonic polyposis. Patients are diagnosed mostly in cancer stages. Colonoscopy shows polyps disseminated around the entire colic frame. Treatment in these cases is total rectocolectomy with ileoanal anastomosis. When working in a general emergency surgery clinic, physicians are often faced with colorectal cancers in different evolutive stages, and mostly they are faced with their complications.
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PMID:Map syndrome (MYH Associated Polyposis) colorectal cancer, etiopathological connections. 2150 84