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)

Neurofibromatosis type 1 (NF1) is a common autosomal dominant condition characterized by benign tumor (neurofibroma) growth and increased risk of malignancy. Dermal neurofibromas, arising from superficial nerves, are primarily of cosmetic significance, whereas plexiform neurofibromas, typically larger and associated with deeply placed nerves, extend into contiguous tissues and may cause serious functional impairment. Malignant peripheral nerve sheath tumors (MPNSTs) seem to arise from plexiform neurofibromas. The NF1 gene, on chromosome segment 17q11.2, encodes a protein that has tumor suppressor function. Loss of heterozygosity (LOH) for NF1 has been reported in some neurofibromas and NF1 malignancies, but plexiform tumors have been poorly represented. Also, the studies did not always employ the same markers, preventing simple comparison of the frequency and extent of LOH among different tumor types. Our chromosome 17 LOH analysis in a cohort of three tumor types was positive for NF1 allele loss in 2/15 (13%) dermal neurofibromas, 4/10 (40%) plexiform neurofibromas, and 3/5 (60%) MPNSTs. Although the region of loss varied, the p arm (including TP53) was lost only in malignant tumors. The losses in the plexiform tumors all included sequences distal to NF1. No subtle TP53 mutations were found in any tumors. This study also reports the identification of both NF1 "hits" in plexiform tumors, further supporting the tumor suppressor role of the NF1 gene in this tumor type.
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PMID:Chromosome 17 loss-of-heterozygosity studies in benign and malignant tumors in neurofibromatosis type 1. 1086 51

Mucocele-like tumor (MLT) of the breast is a rare neoplasm. Although this lesion was considered benign when first described, the concept of a pathologic continuum with mucinous carcinoma was evident in subsequent reports. Only a few cases of MLT have been reported in Korea. We describe a case of MLT associated with ductal carcinoma in situ and mucinous carcinoma in a 34-yr-old female. Histological examination showed multiple mucus-filled cysts of varying size. Extravasated mucin was present in the surrounding stroma. The lining of the cysts in most areas were of flat or cuboidal epithelium and devoid of cellular atypia. The lining epithelium showed proliferative change ranging from atypical ductal hyperplasia to ductal carcinoma in situ, micropapillary type. A microscopic focus of mucinous carcinoma within MLT was also noted. None of the lesions exhibited epithelial reactivity for p53 protein. The patient is alive and well without evidence of disease 54 months after initial treatment. This case supports the concept that MLT encompasses a spectrum of pathologic lesions including benign tumor, atypical ductal hyperplasia, ductal carcinoma in situ, and mucinous carcinoma.
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PMID:Mucocele-like tumor of the breast associated with ductal carcinoma in situ and mucinous carcinoma : a case report. 1151 1

We assessed diagnostic criteria among 38 spindle cell tumors of the urinary bladder and obtained follow-up in 36 patients. Patients comprised 28 males and 10 females aged 2.5 months to 87 years. Hematuria was the commonest presenting symptom (27 patients). After review and immunohistochemical workup, 17 patients had inflammatory pseudotumor (myofibroblastic tumor), 4 postoperative spindle cell nodule, 1 leiomyoma, 13 sarcoma (7 low-grade; 6 high-grade), and 3 carcinoma. Mean age was 38 years for pseudotumor (range 15 to 74), 65 for postoperative spindle cell nodule, 51 for sarcoma, and 76 for carcinoma. Size of pseudotumor averaged 4.4 +/- 0.7 cm (range 1.5 to 13.0), similar to sarcoma, 4.0 +/- 0.6 cm (range 0.5 to 7.0). Similar proportions of benign tumors and sarcomas had muscularis propria invasion. The criteria that best differentiated sarcoma from inflammatory pseudotumor were presence of necrosis at the tumor-detrusor muscle interface in muscle-invasive cases, and nuclear atypia. Sarcoma also had less prominent microvasculature, less variable cellularity, consistently > or =1 mitotic figure per 10 high-power fields, and predominant acute inflammation without plasma cells. p53 protein nuclear immunostaining was moderate, unlike the rare to absent staining in pseudotumors. Because all 12 sarcomas were desmin-negative, we did not call them leiomyosarcoma; they overlapped with benign tumor in epithelial, mesenchymal, and actin immunostaining. Among 12 sarcoma patients, 2 died of tumor (at 3 months). Two of four experienced tumor recurrence after partial cystectomy (2 and 26 months). No pseudotumors recurred after transurethral resection or partial cystectomy, although one patient, 5 months after transurethral resection, had histologically identical pseudotumor that the surgeon considered residual. Another patient with pseudotumor, not a candidate for tumor ablation after transurethral resection, had continued tumor growth and he died of urosepsis. In conclusion, inflammatory pseudotumor, although overlapping with sarcoma in presentation, age range, and size, does not metastasize and remains histologically distinct from low-grade sarcoma.
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PMID:Inflammatory pseudotumor and sarcoma of urinary bladder: differential diagnosis and outcome in thirty-eight spindle cell neoplasms. 1159 76

Mutation of p53 has been implicated in progression of classical Wilms tumor (WT) into the anaplastic variant (AWT), drug resistance, and poor prognosis. Because of prognostic similarities, clear cell sarcoma of the kidney (CCSK) has been classified with AWT and other aggressive pediatric renal tumors, apart from congenital mesoblastic nephroma (CMN), which is instead a relatively benign tumor of neonates. Initially, CCSK and CMN were assumed to be ontologically related, but the role of p53 in the pathogenesis of either disease has not been sufficiently evaluated as in AWT. We examined the status of p53 in CMN and CCSK in comparison to AWT by immunohistochemistry and mRNA analysis of p53, the downstream effector p21(WAF-1/CIP-1) ( p21), the multidrug resistance gene MDR-1, a putative target of p53, and the p53-antagonist Mdm-2. Surprisingly, strong p53 nuclear immunoreactivity was found in cultures from two CMN specimens, but not in frozen or fixed tumor tissue from five other CMN specimens, nor in cell lines or tumor tissue from CCSK. Sequence analysis excluded p53 mutations. The size of the p53 mRNA in CMN and CCSK primary tumors excluded gross deletions or rearrangements. Low levels of Mdm-2 mRNA in CCSK and CMN primary tumors and cultures did not support a role for Mdm-2. Absence of MDR-1 mRNA excluded MDR-1 in the drug-resistant phenotype of CCSK. Cisplatin-induced p21 transactivation assays and G(1) cell cycle arrest analyses showed that p21 transactivation and G(1) arrest occurred in both CCSK and CMN cultures, demonstrating integrity of the p53 signal transduction pathway. Absence of p53 functional abnormalities excluded relationships between CCSK and CMN as in AWT, supporting the association of cellular CMN with congenital fibrosarcomas as more recently proposed.
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PMID:Functional and gene expression analysis of the p53 signaling pathway in clear cell sarcoma of the kidney and congenital mesoblastic nephroma. 1200 18

Oral papilloma is the most frequent benign tumor of the oral cavity but its biological potential for malignant transformation is still to be evaluated. The alteration of apoptosis and uncontrolled cell proliferation is considered to be an important factor in oral tumorigenesis. The aim of our study was to evaluate by immunohistochemistry P53, Bcl-2, CD44 and PCNA expression in oral papillomas with and without dysplasia. We examined a series of 55 oral papillomas, including 12(21.8%) cases of papillomas with epithelial dysplasia. Staining patterns were correlated with sex, age, tumor location, size and presence or absence of epithelial dysplasia. P53 showed positive reaction in 70.9%, PCNA in 80%, CD44 in 50.9% and Bcl-2 in 21.8% of papillomas. There was no correlation between sex, age, tumor size, location and presence of dysplastic epithelium in papillomas. We observed a statistically significant correlation between Bcl-2, CD44 expression and presence of epithelial dysplasia in papillomas. Coexistence of PCNA and P53 positive immunostaining was observed. Papillomas with overexpression of P53 and PCNA showed negative reaction for CD44 protein. The results of our study suggest that overexpression of P53 and PCNA might be an early event in oral tumorigenesis, whereas CD44 and Bcl-2 are potential markers of epithelial dysplasia in oral papillomas.
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PMID:The expression of tumorigenesis markers in oral papilloma. 1259 36

The proto-oncogene product Ron is the receptor for macrophage stimulating protein, a scatter factor that stimulates cell proliferation, prevents apoptosis, and induces an invasive cell phenotype. We investigated the expression of Ron, Ki-67 (proliferation index), p53, and bcl-2 (proapoptotic and antiapoptotic proteins, respectively) in 50 renal tumors (19 clear cell carcinomas, 18 oncocytomas, 7 papillary cell carcinomas, 5 chromophobe cell carcinomas, and 1 carcinoma with sarcomatoid areas). In addition, we studied Ron in normal kidney and in the renal carcinoma cell line Caki-1. Immunostaining and Western blot showed Ron in normal kidney and in all oncocytomas but never in renal cell carcinomas or in Caki-1. In addition, Western blot showed that Ron was expressed in phosphorylated, i.e., active, form. Bcl-2 was strongly expressed in oncocytomas, whereas Ki-67 and p53 were much less expressed in oncocytomas than in carcinomas. These results indicate in Ron a marker that differentiates oncocytoma from the other renal epithelial tumors. We therefore think that Ron may prove to be a new tool for a sound and precise diagnosis of oncocytoma, a benign tumor that cannot always be distinguished from carcinomas at histologic examination. The overexpression of bcl-2, but not p53 in oncocytoma, suggests that the MSP/Ron system sustains the growth of oncocytoma by opposing apoptosis.
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PMID:The Ron proto-oncogene product is a phenotypic marker of renal oncocytoma. 1276 81

To determine whether genetic abnormalities present in primary ovarian tumors can be used to detect cancer cells in peritoneal fluid, we tested 14 ovarian cancers and 1 benign tumor of the ovary for loss of heterozygosity (LOH) at chromosomal arms 13q, 17p, 17q, and 22q and for mutations in the p53 and K-ras genes. In each case, matched primary tumor, normal tissue, and peritoneal fluid were analyzed. The highest frequency of LOH was found on chromosomal arm 17p (42%), followed by chromosomal arm 17q (36%), 22q (30%), and 13q (21%). Identical alterations were detected in matched peritoneal fluid (either peritoneal wash or ascitic fluid) in 3 of the 8 patients with LOH in the tumor (38%). Direct sequence analysis detected p53 mutations in 3 of the 14 malignant tumors (21%) and no (0) K-ras mutations. Identical mutations were detected in matched peritoneal fluid from all 3 patients with p53 mutations. All 8 of the 14 (57%) malignant tumors that showed at least one genetic abnormality were serous adenocarcinoma and identical alterations were detected in 5 of the 8 (62%) matched peritoneal fluid samples. Our findings indicate that molecular abnormalities can be detected in peritoneal fluid from patients with ovarian cancer and may be used to complement current conventional diagnostic procedures for detection of primary ovarian cancer.
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PMID:Molecular analysis of peritoneal fluid in ovarian cancer patients. 1286 Oct 58

We present six cases of a plexiform nerve sheath tumor of childhood that previously had been designated a form of malignant peripheral nerve sheath tumor (MPNST), and we provide evidence that such tumors are in fact benign plexiform cellular schwannomas. At presentation, the four girls and two boys ranged in age from 2 to 15 months with tumors of the leg (four), deep groin and upper thigh (one), and pelvis (one). Of the six lesions, five were congenital and none was associated with type 1 neurofibromatosis. Tumor sizes ranged from 2.0 to 9 cm, with three larger than 5 cm. Three tumors were well circumscribed, two were purely infiltrative, and one had a mixed circumscribed and infiltrative growth pattern. Peripheral nerve involvement was evident in two cases. Grossly, the tumors were multinodular or plexiform in configuration and, on sectioning, lobulated and homogeneously tan without necrosis. Characteristic histologic features included hypercellularity, composition of cells spindle in shape with elongate hyperchromatic nuclei, and indistinct cellular outlines. Their nuclei varied minimally in size and shape but were at least three times the size of typical neurofibroma nuclei. Mitoses were seen in every tumor and in the areas of greatest proliferative activity ranged from 4 to 31/10 high power fields. MIB-1 staining of at least 30% of the cells was noted in three cases. In five cases in which p53 immunoreactions were performed, no nuclear staining was evident. That the tumors are schwannomas was evident from their uniform strong staining for S-100 protein and an ultrastructure in all five cases showing only differentiated neoplastic Schwann cells. Architecturally, the tumors differed from conventional schwannoma and nonplexiform cellular schwannomas by their lack of both well-formed capsules and degenerative changes. Follow-up was available in all cases and ranged from 2 to 13.6 years. All tumors recurred locally and were treated by local resections. With the exception of one child lost to follow-up at 25 months, all the children are alive and free of disease. Our data combined with cases previously reported by Meis-Kindblom and Enzinger show a childhood peripheral nerve tumor unassociated with type 1 neurofibromatosis, occurring most commonly in infants, often presenting as a congenital tumor and, though prone to local recurrence, having no metastatic potential. The behavior is that of a benign tumor, although its often rapid growth, hypercellularity and increased mitotic activity, sometimes locally aggressive behavior, and difficulties encountered in obtaining tumor-free margins are unsettling to pathologist and clinician alike. These features may lead to a misdiagnosis of malignancy, which could result in harmful overtreatment.
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PMID:Congenital and childhood plexiform (multinodular) cellular schwannoma: a troublesome mimic of malignant peripheral nerve sheath tumor. 1450 93

Hepatobiliary cystadenoma and cystadenocarcinoma of the gall bladder have rarely been reported. An 88-year-old Japanese man was admitted to our clinic because of hypochondralgia and jaundice. Imaging techniques revealed hemobilia and a multilocular cystic tumor in the fundus of the gall bladder, and cholecystectomy was performed. Grossly, the tumor (3.5 x 3 x 3 cm) was multicystic, containing seromucous fluid. The tumor was located in the fibromuscular layer and subserosa of the gall bladder fundus, and protruded into the serosal surface, not into gall bladder lumen. The mucosa appeared free of tumor involvement, and no gall stones were recognized. Microscopically, the tumor was located in the fibromuscular layer, subserosa and tiny focus of the mucosal surface. The tumor consisted of mucin-rich benign columnar cells, dysplastic mucous cells, malignant papillotubular cells and invasive carcinoma cells. Malignant and atypical tumor cells were located in the center of the tumor and in the tiny area of the mucosal surface, while benign tumor cells were located in the peripheral portions of the tumor and in the serosal side. Neither ovarian stroma-like mesenchymal stroma nor an oncocytic change in tumor cells was recognized. Non-tumorous gall bladder showed chronic cholecystitis. Immunohistochemically, benign and carcinoma cells were positive for cytokeratins, epithelial membrane antigen, CA19-9, MUC1, MUC5AC and MUC6, and carcinoma cells were also positive for carcinoembryonic antigen and p53 protein. The present case indicates that hepatobiliary cystadenocarcinoma without mesenchymal stroma may occur in the gall bladder of old men, and suggests that hepatobiliary cystadenoma without mesenchymal stroma may transform into hepatobiliary cystadenocarcinoma in the gall bladder.
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PMID:Hepatobiliary cystadenocarcinoma with cystadenoma elements of the gall bladder in an old man. 1462 5

Invasion is generally perceived to be a late event during the progression of human cancer, but to date there are no consistent reports of alterations specifically associated with malignant conversion. We provide evidence that the v-Fos oncogene induces changes in gene expression that render noninvasive normal human diploid fibroblasts highly invasive, without inducing changes in growth factor requirements or anchorage dependence for proliferation. Furthermore, v-Fos-stimulated invasion is independent of the pRb/p16(INK4a) and p53 tumor suppressor pathways and telomerase. We have performed microarray analysis using Affymetrix GeneChips, and the gene expression profile of v-Fos transformed cells supports its role in the regulation of invasion, independent from proliferation. We also demonstrate that invasion, but not proliferation, is dependent on the activity of the up-regulated epidermal growth factor receptor. Taken together, these results indicate that AP-1-directed invasion could precede deregulated proliferation during tumorigenesis and that sustained activation of AP-1 could be the epigenetic event required for conversion of a benign tumor into a malignant one, thereby explaining why many malignant human tumors present without an obvious premalignant hyperproliferative dysplastic lesion.
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PMID:Invasion of normal human fibroblasts induced by v-Fos is independent of proliferation, immortalization, and the tumor suppressors p16INK4a and p53. 1474 71


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