Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P04637 (p53)
 77,613 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The development of adenocarcinoma or carcinoid tumors in atrophic gastritis is widely documented. We report the simultaneous occurrence of gastric adenocarcinoma and carcinoid (composite tumor) in atrophic gastritis, a finding reported only twice before in the literature. This 52-yr-old man with rectal bleeding, epigastric pain, and iron deficiency anemia was noted to have multiple polypoid masses on upper endoscopy. Biopsy revealed features of both adenocarcinoma and carcinoid tumor in a background of atrophic gastritis, leading to a total gastrectomy, lymph node dissection, and liver biopsy. The gastrectomy specimen was characterized by a 6 cm pedunculated polyp and multiple sessile nodular masses between 0.4 and 2.5 cm in the background of a granular mucosa. On microscopic examination, the large polypoid mass corresponded to a well-differentiated adenocarcinoma, intestinal type, infiltrating the wall. The smaller nodules were composed of carcinoid tumors, restricted to the mucosa, or infiltrating the gastric wall. Carcinoid tumor was also seen in the large polypoid mass closely intermingled with adenocarcinoma. The carcinoid tumor metastasized to the liver. Lymph nodes showed both adenocarcinoma and carcinoid tumor. The gastric mucosa was characterized by atrophic gastritis with intestinal metaplasia, neuroendocrine hyperplasia, and microcarcinoids. The adenocarcinoma stained strongly for CK7, CK 20, MIB-1, and focally for chromogranin and synaptophysin. The carcinoid tumor was negative for CK7, CK 20 and MIB-1, and was positive for chromogranin and synaptophysin. Overexpression of p53 was noted only in the adenocarcinoma. Electron microscopy revealed neurosecretory granules in the carcinoid characteristic of a neuroendocrine tumor. Composite tumor can occur in the setting of atrophic gastritis. The findings in this patient reinforce the concept that the epithelial and neuroendocrine cells of the gastrointestinal tract both result from multidirectional differentiation of a primitive cell.
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PMID:Combined adenocarcinoma and carcinoid tumor in atrophic gastritis. 1245 98

Adenocarcinoid of the appendix is a rare tumor with the histological features of both adenocarcinoma and carcinoid tumor. However, its biological behavior and malignant potential are still unclear. We treated two patients with this unusual tumor; a 60-year-old man and a 79-year-old woman. Both patients were initially diagnosed with acute appendicitis followed by an appendectomy. At surgery, the appendix was seen to be acutely inflamed without any macroscopic signs of tumor. Postoperative histological analysis revealed an adenocarcinoid tumor in the appendix, which had spread diffusely into its wall without forming a mass. Immunohistochemical staining with p53, MIB-1, bcl-2, and carcinoembryonic antigen suggested that neither of these tumors were particularly aggressive. Adenocarcinoid of the appendix is a rare tumor, which is very difficult to diagnose preoperatively and even macroscopically, making histological examination essential.
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PMID:Adenocarcinoid of the appendix: report of two cases. 1273 35

A unique tumor measuring 8 x 8 x 5 mm and composed of adenoma, adenocarcinoma and mixed carcinoid-adenocarcinoma arising in the ascending colon is reported. The mixed carcinoid-adenocarcinoma, in which adenocarcinomatous and carcinoid components intermingled, originated in the mucosa, penetrated the muscularis mucosa and extended into the submucosa. Immunohistochemically, carcinoid cells were positive for neuroendocrine markers and adenocarcinoma cells were intracytoplasmicly positive for carcinoembryonic antigen. Ultrastructurally, membrane-bound electron dense granules varying in shape, size and electron density were detected in the cytoplasm of carcinoid cells. No mutations of p53 and k-ras genes were detected in adenomatous, adenocarcinomatous or mixed carcinoid-adenocarcinoma components. The morphological appearances of the present case strongly suggests the histogenesis of this tumor in an adenoma-adenocarcinoma-carcinoid tumor sequence.
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PMID:Adenoma, adenocarcinoma and mixed carcinoid-adenocarcinoma arising in a small lesion of the colon. 1282 11

Surgically resected specimens of 13 carcinoid tumors of the lung including nine typical carcinoids and four atypical carcinoids, and eight salivary gland type carcinomas (six mucoepidermoid carcinomas and two adenoid cystic carcinomas) were analyzed regarding p53 expression, loss of heterozygosity (LOH) in chromosome 3p, 9p, and K-ras mutation. The overexpression of p53 was identified in four atypical carcinoid tumors, one mucoepidermoid carcinoma, and one adenoid cystic carcinoma, however, none of typical carcinoids showed p53 immunoreactivity. LOH in 3p14 was demonstrated in three of seven informative cases in all tumors. LOH in 9p was demonstrated in two of five informative cases in all tumors. Two of three cases with LOH at 3p14 had a poor prognosis, one of which also had LOH at 9p. No mutation of the K-ras gene was observed in any of these tumors. These data thus indicate that p53 overexpression might distinguish atypical carcinoid tumors from typical tumors and might therefore be useful as an adjunct modality in the differential diagnosis of pulmonary carcinoid tumors. The presence of LOH at 3p14 or 9p may thus help to identify lung cancer patients with a poor prognosis.
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PMID:Genetic alteration in carcinoid tumors of the lung. 1287 35

We studied 10 cases of primary pure testicular neuroendocrine carcinoma. Patients were between 16 and 48 years old and had testicular swelling with pain or a painless testicular mass and no history of neuroendocrine carcinoma or other malignant neoplasm. All underwent orchiectomy. The tumors were low (n = 9) and intermediate (n = 1) grades with a variegated histologic appearance characterized by a nesting pattern, cords of neoplastic cells with rosettes, or sheets of neoplastic cells. Mitotic activity was lacking in 9 cases. In 1 case, mitotic figures ranged from 7 to 8 per 10 high-power fields, and cellular atypia and comedo-like necrosis were present. Immunohistochemical studies using a keratin cocktail, chromogranin, synaptophysin, epidermal growth factor, p53, placental-like alkaline phosphatase, and CD117 (c-kit) were performed in all cases. Keratin, chromogranin, and synaptophysin were positive in all tumors. Clinical follow-up information was obtained for 6 patients (range, 12-60 months): 5 with low-grade tumors were alive 24 to 60 months after diagnosis; 1 with an intermediate-grade tumor died of tumor 12 months after initial diagnosis. The behavior of these tumors, while in the testicular region, correlates well with the histologic grade. We propose replacing the term testicular carcinoid with neuroendocrine carcinoma, which better reflects the nature of these neoplasms.
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PMID:Neuroendocrine carcinomas (carcinoid tumor) of the testis. A clinicopathologic and immunohistochemical study of ten cases. 1498 45

Telomerase activity was examined by the telomeric repeat amplification protocol (TRAP) assay in 38 neuroendocrine (NE) lung tumours. A significantly (p = 0.001) different frequency of telomerase positivity was observed among different histological tumour types. Specifically, a positive TRAP signal was observed in 14 of 15 (93%) small cell lung cancers (SCLCs), 7 of 8 (87%) large-cell NE carcinomas (LCNECs), and only 1 of 15 (7%) typical carcinoid tumours. When telomerase activity was correlated with the gene product-based immunophenotypic profile of individual tumours, it was found that the absence of telomerase activity was associated with a lack of bcl-2, p53, and c-kit expression, and characterized by a low proliferation index consistent with the absence of cdk-4 expression and the presence of the cdk inhibitor Rb. Such a phenotype was appreciable in most of the carcinoid tumours. Conversely, telomerase-positive tumours generally showed an immunophenotype consistent with gene product alterations (including high expression of bcl-2, p53, and c-kit, and loss of Rb) and were characterized by a high proliferation index. These telomerase data support the previously reported evidence for two genetically unrelated groups of NE lung tumours (SCLC, and to some extent LCNEC, versus carcinoid tumours) that have distinct phenotypic profiles.
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PMID:Differential expression of telomerase activity in neuroendocrine lung tumours: correlation with gene product immunophenotyping. 1295 25

The most characteristic endocrine tumours of the testis are germ cell tumours and sex cord/gonadal stromal tumours. They include the primary carcinoid, the relation of which to teratomas is still unclear. In general, gonadal stromal tumours are rare, however, endocrine activity occurs in at least 10%-20%. Among gonadal stromal tumours, only Leydig cell tumours and Sertoli cell tumours are of practical importance. Endocrine disorders are mostly related to Leydig cell tumours (gynaecomastia, pubertas praecox). Although less frequent than the other gonadal stromal tumours, they can, in principle, occur. The large cell calcifying Sertoli cell tumour occurs in association with other complex disorders (i.e. Peutz-Jeghers syndrome). Valuable markers are: inhibin, calretinin, cytokeratin, melan-A, CD-99, Ki-67, androgen receptor and p53. As the conventional morphology and immunohistological markers frequently overlap, unclear cases should be referred to specialised centres.
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PMID:[Endocrine tumors of the testis]. 1451 79

Goblet cell carcinoid is a relatively rare neuroendocrine tumor of the vermiform appendix with poorly understood molecular pathogenesis. We studied the clinicopathologic features and genetic alterations, including allelic loss of chromosomes 11q, 16q, and 18q; sequencing of the K-ras, beta-catenin, and DPC4 (SMAD4) genes; and p53 overexpression and loss of DPC4 by immunohistochemistry; in 16 goblet cell carcinoids. We compared the allelic loss in goblet cell carcinoids to those in 18 gastrointestinal carcinoid tumors. For goblet cell carcinoids, appendiceal perforation was the most common (70%, 7/10) clinical presentation. The mean tumor size was 2.0 +/- 1.5 cm (range, 0.4 to 4.5 cm). The tumor invaded to appendiceal serosa in 50% (8/16) of patients, and two patients had metastasis in lymph nodes or adjoining viscera. With mean follow-up of 24 +/- 14 months (median, 23 mo), 1 of 10 patients had died of disease, and 2 others had tumor recurrence. All four patients with metastases, recurrences, and/or death from disease had serosal involvement at presentation (P =.02). Loss of heterozygosity of chromosome 11q was present in 25% of goblet cell carcinoids, 14% of ileal carcinoid tumors, and 9% of nonileal carcinoid tumors; of chromosome 16q in 38%, 29%, and 0 (P =.02); and of chromosome 18q in 56%, 86%, and 9% (P =.002), respectively. No mutations of K-ras, beta-catenin, or DPC4 genes; p53 overexpression; or loss of staining for DPC4 was present in any tumors. These findings suggest that allelic loss of chromosomes 11q, 16q, and 18q in goblet cell carcinoids and ileal carcinoids may have an important role in the pathogenesis of these tumors.
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PMID:Genetic alterations in goblet cell carcinoids of the vermiform appendix and comparison with gastrointestinal carcinoid tumors. 1468 18

Carcinoid tumors originate from the neuroendocrine cells throughout the body and are capable of producing various peptides. Their clinical course is often indolent but can also be aggressive and resistant to therapy. We examined all aspects of carcinoid tumors including the molecular biology oncogenesis, role of angiogenesis, recent advances in imaging, and therapy. The Medline and Cancerlit databases were searched using carcinoid as the keyword. English language manuscripts were reviewed and relevant references from a total of 7741 were found. All titles were screened and all the relevant manuscripts were analyzed; we found 307 references pertinent to the history, epidemiology, clinical behavior, pathology, pathophysiology, molecular biology, radiologic imaging, supportive care of carcinoid syndrome, and results of therapeutic clinical trials. Management of patients with carcinoid tumors requires an understanding of the disease process and a multimodality approach. Introduction of long-acting somatostatin analogues has resulted in significant advances in the palliative care of patients with carcinoid syndrome. However, advanced carcinoid tumor remains incurable. Existing therapies for advanced disease have low biologic activity, high toxicity, or both. Clearly, more research is necessary in the areas of molecular biology, targeted therapy, and development of new drugs Future advances in this field need to focus on clinical and biological predictors of outcome. Early works in the area of tumor biology such as the role of p53, bcl-2, bax, MEN1, FGF TGF PDGF and VEGF expression are of interest and need to be explored further.
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PMID:Carcinoid--a comprehensive review. 1469 Jan 53

Neuroendocrine tumours (NETs) originate in tissues that contain cells derived from the embryonic neural crest, neuroectoderm and endoderm. Thus, NETs occur at many sites in the body, although the majority occur within the gastro-entero-pancreatic axis and can be subdivided into those of foregut, midgut and hindgut origin. Amongst these, only those of midgut origin are generally argentaffin positive and secrete serotonin, and hence only these should be referred to as carcinoid tumours. NETs may occur as part of complex familial endocrine cancer syndromes, such as multiple endocrine neoplasia type 1 (MEN1), although the majority occur as non-familial (i.e. sporadic) isolated tumours. Molecular genetic studies have revealed that the development of NETs may involve different genes, each of which may be associated with several different abnormalities that include point mutations, gene deletions, DNA methylation, chromosomal losses and chromosomal gains. Indeed, the foregut, midgut and hindgut NETs develop via different molecular pathways. For example, foregut NETs have frequent deletions and mutations of the MEN1 gene, whereas midgut NETs have losses of chromosome 18, 11q and 16q and hindgut NETs express transforming growth factor-alpha and the epidermal growth factor receptor. Furthermore, in lung NETs, a loss of chromosome 3p is the most frequent change and p53 mutations and chromosomal loss of 5q21 are associated with more aggressive tumours and poor survival. In addition, methylation frequencies of retinoic acid receptor-beta, E-cadherin and RAS-associated domain family genes increase with the severity of lung NETs. Thus the development and progression of NETs is associated with specific genetic abnormalities that indicate the likely involvement of different molecular pathways.
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PMID:Genetics of neuroendocrine and carcinoid tumours. 1471 56


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