Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0178874 (tumor progression)
 40,807 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

This study was designed to characterize the expression profiles of nine bladder cancer cell lines (T24, J82, 5637, HT1376, RT4, SCaBER, TCCSUP, UMUC-3, and HT1197) using cDNA microarrays (8976 genes and expressed sequence tags). Novel targets involved in bladder cancer progression of potential clinical relevance were validated by immunohistochemistry using tissue microarrays of primary bladder tumors (n = 193 cases). Hierarchical clustering classified uroepithelial cells based on their histopathogenesis and cell cycle alterations. Keratin 10 and caveolin-1 transcripts were more abundant in tumor cells from squamous and invasive origin. Their combined expression was shown to stratify bladder tumors and define squamous differentiation. To assess the robustness of the clustering analysis, a bootstrap resampling technique was used. This grouped tumor cell lines based on their biological properties, including cell cycle and cell adhesion features. E-cadherin, zyxin, and moesin were identified as genes differentially expressed in these clusters and related to the p53, RB, and INK4A status of the cell lines. Loss of these adhesion molecules was associated with stage and grade in primary tumors (P < 0.05), and moesin expression was also associated with survival (P = 0.01). Deregulation of cell cycle and apoptotic pathways, such as mutations or altered expression of p53, pRB, and INK4A (p16), is necessary for uroepithelial transformation. However, it appears that deregulation of cell adhesion is a common event associated with tumor progression in uroepithelial neoplasms.
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PMID:Molecular profiling of bladder cancer using cDNA microarrays: defining histogenesis and biological phenotypes. 1600 74

To understand the role of gene promoter methylation in neoplastic evolution and progression, the methylation changes associated with 15 candidate tumor suppressor genes were studied throughout stages of tumor progression involving intraductal papillary mucinous neoplasms (IPMN) of the pancreas. Genomic DNA from 28 pancreatic IPMN tissue samples, categorized histologically as non-invasive intraductal IPMN (n = 3), IPMN with carcinoma in situ (n = 7), IPMN with microinvasion <1 mm (n = 4), and infiltrative IPMN with associated adenocarcinoma (n = 14), was modified by bisulfite treatment and analyzed with methylation-specific PCR (MSP). Promoter methylation of at least one tumor suppressor gene was present in 26/28 (92%) of the IPMNs. The cell cycle control genes, p16 and p73, were methylated frequently (>50%) in both non-invasive and invasive tumors. APC methylation was discovered in <10% of the non-invasive IPMNs versus 45% of the IPMNs associated with infiltrative adenocarcinoma, P = 0.040. Mismatch repair genes, hMLH1 and MGMT, were frequently methylated in the invasive IPMNs compared with the non-invasive tumors (38 versus 10% and 45 versus 20%, respectively) as was E-cadherin (38 versus 10%), P = 0.11. Multiple gene methylation at greater than three loci was present in 55% of the invasive tumors compared with 20% of the non-invasive tumors, P = 0.075. Lymph node status did not predict multi-gene methylation among tumors associated with invasive cancer. Compared with non-invasive IPMNs of the pancreas, IPMNs associated with adenocarcinoma demonstrate higher rates of aberrant tumor suppressor gene methylation. The sequential acquisition of hypermethylation at multiple gene promoter sites may explain tumor progression in IPMNs and other malignancies. Detection of methylation within selected genes may afford an accurate diagnostic molecular marker and predictor of neoplastic behavior.
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PMID:Molecular progression of promoter methylation in intraductal papillary mucinous neoplasms (IPMN) of the pancreas. 1258 67

Our report describes a 66-yr-old man who underwent surgical resection of the pancreas twice within a period of 3 yr for primary and recurrent intraductal papillary mucinous tumors (IPMTs). During the second operation, a minute invasive ductal carcinoma (IDC) was accidentally discovered in the resected specimen of the residual pancreas. The similarity and continuity between this IDC and recurrent IPMT were not recognized histologically. A solid tumor was found in the hepatoduodenal ligament 3 mo after the second operation. We performed a third operation, performing laparotomy and intra-operative radiotherapy, but could not extirpate the tumor. A biopsy specimen obtained from the tumor during this third operation revealed adenocarcinoma, and the patient later died because of tumor progression. We immunohistochemically analyzed the expression of HER-2/neu, Smad4, p16, p21, p53, mucin immunophenotypes and the Ki-67 labeling index in this series of pancreatic-duct neoplasias. Overexpression of HER-2/neu and loss of Smad4 were detected in the minute IDC, which was very different from the immunohistochemical features of both the primary and recurrent IPMTs. The IDC also showed a MUC1-positive/MUC2-negative phenotype. Therefore, we suggest that de novo IDC may occur in IPMT patients, especially those with multiple tumor recurrence. The present case may be helpful in understanding the pathogenesis of pancreatic duct lesions.
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PMID:Minute invasive ductal carcinoma of the residual pancreas after distal pancreatectomy for intraductal papillary-mucinous tumor. 1262 31

Sixty-one glioblastomas have been studied, subdivided into the categories of classic glioblastomas (GBM) and glioblastomas with astrocytic (GBA) and oligodendroglial (GBO) differentiated areas. On surgical samples, TP53, Mdm2, CDKN2A/p16-p14 alterations were studied by molecular biology techniques and by immunohistochemistry. It has been found that Mdm2 amplification was more frequent in GBM than in GBA and GBO, that p14ARF was inactivated in a high percentage of cases in the three tumor categories. Both these and other alterations did not reach a statistical significance, with the exception of CDKN2A/p16 homozygous deletion which showed the highest frequency in GBO. The latter finding could be in line with the observation that CDKN2A/p16 inactivation is a step in the molecular pathway to tumor progression in oligodendrogliomas. TP53 mutations and Mdm2 amplifications were mutually exclusive, whereas TP53 mutations and CDKN2A/p14 inactivation coexisted in 5 cases. The alterations of the p53/Mdm2/p14ARF pathway occurred in 73% of cases and in 80% of cases if CDKN2A homozygous deletions were associated. All glioblastomas with gemistocytic areas showed p14ARF inactivation. Immunohistochemistry showed higher percentages of positivity in comparison with molecular genetics, but with similar variations.
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PMID:Deregulation of the p14ARF/Mdm2/p53 pathway and G1/S transition in two glioblastoma sets. 1262 47

Reduced expression of the p16 gene product (protein), an inhibitor of cyclin-D-dependent protein kinase which regulates cell cycle at the G1/S boundary, is implicated in tumor progression in various neoplasms. Hypermethylation of the p16 promoter gene has recently been suggested to be one of the reasons for the reduced protein expression. To explore the role of p16 in the biological behavior of adenoid cystic carcinomas (ACC), we investigated the immunohistochemical expression of p16 protein in 38 ACC tumors (32 primary, 3 recurrent, and 3 metastatic tumors) and the methylation status of its promoter gene. We also examined their relationships to the histological grade of malignancy. Positive reaction of p16 protein was demonstrated in the nuclei of luminar cuboidal cells in areas with tubular patterns. The reactions were reduced in the areas with solid or large cribriform patterns. The levels of p16 expression correlated with the histological grade of malignancy. Recurrent or metastatic tumors did not differ with respect to histological grades from the original tumor except for 1 case, in which p16 expression was reduced compared to the primary tumor. Methylation-specific PCR demonstrated the hypermethylation status of the p16 promoter gene in 4 of 22 primary tumors (21%), all of which showed negative or low expression of the p16 protein. The study indicated that p16 expression was reduced in ACC cases of higher histological grade of malignancy and that hypermethylation of its promoter gene may be involved in its process in some cases.
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PMID:Expression of p16 protein and hypermethylation status of its promoter gene in adenoid cystic carcinoma of the head and neck. 1262 3

Gallbladder carcinomas can be highly lethal neoplasms. Relatively little is known about the genetic abnormalities that underlie these tumors, particularly with respect to their timing in neoplastic progression. The authors evaluated 5 noninvasive dysplasias and 33 invasive gallbladder carcinomas (6 small cell carcinomas, 27 non-small cell carcinomas, of which 16 were accompanied by an in situ carcinoma component) for expression of the protein products of the p16, p53, Dpc4, and pRB tumor suppressor genes by immunohistochemistry. Neoplasms were also evaluated for the presence of activating K-ras oncogene mutations. Seventy-five percent of non-small cell gallbladder carcinomas demonstrated loss of p16 expression, whereas 63% accumulated high levels of p53. Loss of Dpc4 and pRB expression was less frequent, seen in 19% and 4% of the neoplasms, respectively. Thirty percent of neoplasms harbored activating K-ras mutations. In contrast, 100% of the small cell carcinomas of the gallbladder demonstrated inactivation of the pRB/p16 pathway; 67% showed loss of pRB expression, and the other 33% lost p16 expression. Eighty-three percent of small cell carcinomas accumulated high levels of p53, whereas loss of Dpc4 expression and activating K-ras mutations were not found. Among 15 evaluable in situ components, 13 harbored the same alterations found in the invasive component. Inactivation of p16 and p53 occur in the majority of non-small cell gallbladder carcinomas. Dpc4 inactivation and K-ras mutations occur in a significant minority of cases. pRB loss is uncommon in non-small cell gallbladder carcinoma, but virtually all small cell carcinomas inactivate the p16/pRB pathway, usually by retinoblastoma protein loss. It is noteworthy that all of these alterations occur at the level of carcinoma in situ.
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PMID:Immunohistochemical and genetic analysis of non-small cell and small cell gallbladder carcinoma and their precursor lesions. 1269 94

Tissue hypoxia is a characteristic property of cervical cancers that makes tumors resistant to chemo- and radiation therapy. Erythropoietin (Epo) is a hypoxia-inducible stimulator of erythropoiesis. Acting via its receptor (EpoR), Epo up-regulates bcl-2 and inhibits apoptosis of erythroid cells and rescues neurons from hypoxic damage. In addition to human papillomavirus infection, increased bcl-2 expression and decreased apoptosis are thought to play a role in the progression of cervical neoplasia. Using reverse transcriptase-polymerase chain reaction and Western blotting we showed that HeLa and SiHa cervical carcinoma cells and human cervical carcinomas express EpoR, and that hypoxia enhances EpoR expression. Exogenous Epo stimulated tyrosine phosphorylation and inhibited the cytotoxic effect of cisplatin in HeLa cervical carcinoma cells. Using immunohistochemistry, we examined the expression of Epo, EpoR, p16, hypoxia-inducible factor (HIF)-1alpha, and bcl-2 in benign and dysplastic cervical squamous epithelia and invasive squamous cell carcinomas (ISCCs). EpoR expression in benign epithelia was confined to the basal cell layers, whereas in dysplasias it increasingly appeared in more superficial cell layers and showed a significant correlation with severity of dysplasia. Diffuse EpoR expression was found in all ISCCs. Expression of Epo and HIF-1alpha was increased in dysplasias compared to benign epithelia. Focal Epo and HIF-1alpha expression was seen near necrotic areas in ISCCs, and showed correlation in their spatial distribution. Significant correlation was found between expression of EpoR, and p16 and bcl-2 in benign and dysplastic squamous epithelia. Our results suggest that increased expression of Epo and EpoR may play a significant role in cervical carcinogenesis and tumor progression. Hypoxia-inducible Epo signaling may play a significant role in the aggressive behavior and treatment resistance of hypoxic cervical cancers.
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PMID:Hypoxia-inducible erythropoietin signaling in squamous dysplasia and squamous cell carcinoma of the uterine cervix and its potential role in cervical carcinogenesis and tumor progression. 1275 37

Transforming growth factor-beta (TGF-beta ) has dual and paradoxical functions as a tumor suppressor and promoter of tumor progression and metastasis. TGF-Ji-mediated growth inhibition is gradually lost during melanoma tumor progression, but there are no measurable defects at the receptor level. Furthermore, melanoma cells release high levels of TGF-beta to the microenvironment, which upon activation induces matrix deposition, angiogenesis, survival, and transition to more aggressive phenotypes. The SKI and SnoN protein family associate with and repress the activity of Smad2, Smad3, and Smad4, three members of the TGF-fl signaling pathway. SKI also facilitates cell-cycle progression by targeting the RB pathway by at least two ways: it directly associates with RB and represses its activity when expressed at high levels, and indirectly, it represses Smad-mediated induction of p21(Waf-1) This results in increased CDK2 activity, RB phosphorylation,and inactivation. Therefore, high levels of SKI result in lesions to the RB pathway in a manner similar to p16 (INK4a) loss. SKI mRNA and protein levels dramatically increase during human melanoma tumor progression. In addition,the SKI protein shifts from nuclear localization in intraepidermal melanoma cells to nuclear and cytoplasmic in invasive and metastatic melanomas. Here, I discuss the basis for repression of intracellular TGF-beta signaling by SKI, some additional activities of this protein, and propose that by disrupting multiple tumor suppressor pathways, SKI functions as a melanoma oncogene.
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PMID:Repression of TGF-beta signaling by the oncogenic protein SKI in human melanomas: consequences for proliferation, survival, and metastasis. 1279 38

Most human tumors display inactivation of the p53 and the p16(INK4)/pRb pathway. The Ink4a/alternative reading frame (ARF) locus encodes the p16(INK4a) and p14(ARF) (murine p19(ARF)) proteins. p16(INK4a) is deleted in 40-60% of breast cancer cell lines, and p16(INK4a) inactivation by DNA methylation occurs in < or =30% of human breast cancers. In mice genetically heterozygous for p16(INK4a) or Ink4a/Arf, predisposition to specific tumor types is enhanced. Ink4a/Arf(+/-) mice have increased E micro -Myc-induced lymphomagenesis and epidermal growth factor receptor-induced gliomagenesis. ErbB2 (epidermal growth factor receptor-related protein B2) is frequently overexpressed in human breast cancer and is sufficient for mammary tumorigenesis in vivo. We determined the role of heterozygosity at the Ink4a/Arf locus in ErbB2-induced mammary tumorigenesis. Compared with mouse mammary tumor virus-ErbB2 Ink4a/Arf(+/-) mice, mouse mammary tumor virus-ErbB2 Ink4a/Arf(wt) mammary tumors showed increased p16(INK4a), reduced Ki-67 expression, and reduced cyclin D1 protein but increased mammary tumor apoptosis with no significant change in the risk of developing mammary tumors. These studies demonstrate the contribution of Ink4a/Arf heterozygosity to tumor progression is tissue specific in vivo. In view of the important role of Ink4a/Arf in response to chemotherapy, these transgenic mice may provide a useful model for testing breast tumor therapies.
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PMID:The role of Ink4a/Arf in ErbB2 mammary gland tumorigenesis. 1281 Jun 76

Members of the CCAAT/enhancer-binding protein (C/EBP) family of transcription factors are involved in the regulation of proliferation and differentiation of the mammary gland. In order to investigate the role of C/EBPalpha, -beta and -delta in breast cancer, we performed western blot analysis and partly immunohistochemistry in 75 mammary carcinomas, 10 normal mammary tissue samples and four mammary cell lines. Expression levels of both C/EBPalpha isoforms, C/EBPbeta isoforms LAP1, LAP2 (liver-enriched transcriptional activating proteins), and LIP (liver-enriched transcriptional inhibitory protein), and C/EBPdelta in the tumors were correlated with clinicopathological tumor parameters, expression of estrogen and progesterone receptors (ER, PR), Ki67 immunostaining, and expression of seven cell-cycle regulatory proteins which had been analyzed before. High C/EBPalpha and -delta protein levels correlated significantly with expression of cell-cycle promoters (cyclin D1 and E) and cell-cycle inhibitory proteins (Rb, p27, p16), but with none of the established prognostic parameters. In contrast, statistically significant relationships of the full-length C/EBPbeta isoform LAP1 and a negative estrogen receptor status, high grading, nodal involvement, and high cyclin E and p16 expression were found. For the shorter isoform LIP, correlations with an ER-negative phenotype and high Ki67 immunostaining were detected, and high histological grading (G3) correlated with lower LAP/LIP ratio. These results suggest that high C/EBPbeta expression might be involved in tumor progression and indicative of an unfavorable prognosis.
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PMID:Expression of the CCAAT/enhancer-binding proteins C/EBPalpha, C/EBPbeta and C/EBPdelta in breast cancer: correlations with clinicopathologic parameters and cell-cycle regulatory proteins. 1282 52


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