Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0546837 (esophageal cancer)
 8,907 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We examined the expression of cyclin D1 mRNA in two human carcinoma cell lines (A431 and TT) and 17 specimens of esophageal cancer with in situ hybridization. Cyclin D1 mRNA was overexpressed in the cytoplasm of cancer cells that showed cyclin D1 gene amplification by Southern blot hybridization. Cyclin D1 antigen was overexpressed in the nucleus of these cancer cells. The distribution of cyclin D1 mRNA-positive cells was similar to that of cyclin D1 antigen-positive cells in the cancer tissues. We then attempted to correlate overexpression of cyclin D1 antigen and prognosis, by using 55 formalin-fixed, paraffin-embedded specimens of esophageal cancer. The overall 5-year survival of patients with strongly staining tumors was significantly lower than that of patients with weakly or nonstaining tumors (7 versus 59%; P < 0.01). There was no significant correlation between cyclin D1 expression and other clinicopathological factors. These results suggest that cyclin D1 may play an important role in carcinogenesis and that cyclin D1 overexpression may be a useful prognostic factor in esophageal cancer.
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PMID:Overexpression and localization of cyclin D1 mRNA and antigen in esophageal cancer. 774 10

The prognostic factors for esophageal cancer from the viewpoint of molecular biology are reviewed. Among several oncogenes and suppressor genes erbB, int2/hst1/Cyclin D1 and MDM2 gene amplifications are significant prognostic factors for esophageal cancer. The value of p53 mutation, and expression of matrix metalloproteinase (MMPs) in the prediction of patients' survival are controversial, so further research is needed. High expression of tumor proliferation-related factors (Ki67, PCNA, and AgNOR), abnormalities of adhesion molecule (E-Cadherin, alpha-Catenin), activation of autocrine mechanism of growth factor (EGFR-TGF alpha, EGF), and DNA ploidy pattern, which is thought to be the result of an accumulation of genomic abnormalities are also prognostic factors for esophageal cancer.
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PMID:[Prognostic factors for esophageal cancer--from the viewpoint of molecular biology]. 868 32

D-type cyclins being considered as oncogenes promote progression of the cell through the G1 phase of the cell cycle by CDK4 mediated phosphorylation of the retinoblastoma protein. The activities of CDK4 is constrained by inhibitors such as p16, the product of the CDKN2 in tumor cells and primary tumors suggests that p16 acts as a tumor suppressor. We examined these proteins and genes by immunohistochemistry and in situ hybridization techniques in 41 primary esophageal cancers. Overexpression of cyclin D1 was revealed in 26/41 samples (63.4%) and also in the mucosa adjacent to the cancers in 10 of 26 cyclin D1 overexpression samples, which also have high levels of cyclin D1. P16 was undetectable in 13 of 41 samples. Interestingly, 17 of 24 Rb positive cancers had no or low p16, while 9 Rb-negative cancers showed high levels of p16. These results suggest that the overexpression of cyclin D1 may be a common molecular abnormality and an early molecular event in esophageal cancer, followed either by Rb loss, as occurred in Rb negative samples, or by loss of p16, as occurred in p16 negative samples. Cyclin D1 overexpression and Rb inactivation can coexist in esophageal cancer. However, there is a reciprocity between Rb inactivation and p16 expression in esophageal cancer. Thus, abnormality in the negative feedback regulatory pathway of cyclin D1/CDK4, Rb and p16 may be involved in the molecular mechanism of esophageal cancer.
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PMID:[The expression of Rb, p16 and cyclin D1 in 41 esophageal cancers]. 938 58

Cyclin D1 is a cell-cycle regulator essential for G1 phase progression and a candidate proto-oncogene implicated in pathogenesis of several human tumor types including esophageal cancers. Association between cyclin D1 gene amplification and clinical outcome was examined using southern blotting in 45 patients with primary esophageal cancer. In cases showing gene amplification, expression levels of mRNA and gene product were further examined by northern blotting, western blotting and immunohistochemical analyses. Amplification of cyclin D1 gene was found in 14 of 45 patients (31. 1%). There was no association between gene amplification and clinicopathological parameters but the frequency of hematogenous recurrence in cases with gene amplification was significantly higher than that in cases without amplification in 30 patients undergoing curative surgery (70.0% vs 25.0%, p<0.05). Furthermore, cumulative survival rate of cases with gene amplification was significantly lower than that of cases without amplification (p<0.05). Overexpression of cyclin D1 mRNA was observed in 12 of 14 cases (85. 7%) showing gene amplification but overexpression of its protein was found in only four cases (28.6%). Amplification of the cyclin D1 gene is a reliable prognostic factor and post-translational modification of this gene may play a functionally important role in development of primary esophageal cancer.
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PMID:Amplification and overexpression of cyclin D1 in aggressive human esophageal cancer. 945 16

Cyclin D1, which functionally competes with the tumor suppressor genes retinoblastoma (Rb) and p16INK4, is widely recognized as an oncogene. P27KIP1, which inhibits the cyclin D1-CDK4 complex, is also a putative tumor suppressor gene. In order to evaluate the regulatory interaction of these molecules, a retrospective series of tissues from 66 patients with esophageal squamous cell carcinoma was evaluated immunohistochemically for the expressions of cyclin D1, Rb, p16INK4 and p27KIP1. The expressions of these molecules were correlated with the proliferation cell nuclear antigen (PCNA) index as an indicator of cell proliferation. Cyclin D1 was overexpressed (++) in 28 cases (42%), Rb was lost (-) in 19 cases (24%), p16INK4 was lost (-) in 37 cases (56%) and p27KIP1 was lost (-) in 27 cases (41%). Taken together, disorder of at least one or more of these molecules was observed in 62 cases (92%). Expression of cyclin D1 and p16INK4 was negatively correlated (p<0.03), while expression of cyclin D1 and p27KIP1 was positively correlated (p<0.0004). We found strong overall correlation between expression of cyclin D1 and the PCNA index (p<0.0001), however expression of p16INK4 and p27KIP1 was significantly correlated with the PCNA index in tumors devoid of cyclin D1 overexpression (p<0.03 and p<0.02 respectively). Thus, it was found that cyclin D1 plays a major role and closely related to abnormal cell proliferation in esophageal cancer, however assessment of p16INK4 and p27KIP1 status, particularly in tumors devoid of cyclin D1 overexpression, is necessary for comprehensive evaluation of cancer cell proliferation. Furthermore, expression of cyclin D1 is correlated with that of p16INK4 and p27KIP1 in squamous cell carcinoma of the esophagus.
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PMID:Effect of cyclin D1 and associated proteins on proliferation of esophageal squamous cell carcinoma. 968 78

Cyclin D1 is frequently overexpressed in human esophageal cancer. We examined the possible role of cyclin D1 overexpression on specific malignant properties of tumor cells using a series of eight human esophageal cancer cell lines that express different levels of cyclin D1. We did not find a simple correlation between levels of cyclin D1 expression and anchorage-independent growth, production of angiogenic factors, or tumorigenicity in nude mice, suggesting that other factors can influence these parameters. We did, however, obtain evidence that tumorigenicity appeared to require both the capacity for anchorage-independent growth and the production of angiogenic factors. To better assess the specific role of cyclin D1, we stably expressed an antisense cyclin D1 cDNA construct in the tumorigenic cell line TTn. This significantly decreased anchorage-independent growth and VEGF production and led to a loss of tumorigenicity in nude mice. Furthermore, these cells diplayed a marked increase in sensitivity to antitumor agents and to Fas antibody-induced apoptosis. Taken together, these findings suggest that the overexpression of cyclin D1 can confer esophageal cancer cells with enhanced malignancy through increases in anchorage-independent growth and VEGF production, and down-regulation of Fas expression, thus suggesting novel functions of the cyclin D1 protein in tumor progression.
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PMID:Overexpression of cyclin DI contributes to malignant properties of esophageal tumor cells by increasing VEGF production and decreasing Fas expression. 1201 32

Alterations of cell cycle-regulated genes play an important role in the process of carcinogenesis, and some of them are thought to be prognostic factors in esophageal cancer. The expressions of p53, p16, pRB and Cyclin D1 proteins were evaluated immunohistochemically in 144 patients who underwent curative esophagectomy without any adjuvant therapy before surgery. p53 overexpression was observed in 99 (69%) out of the 144 patients. No significant correlation was noted between p53 and any other gene expression. p16 expression was observed in 12 (8.3%) out of all cases. A negative correlation was recognized between p16 and Cyclin D1 expression (P=0.0004). pRB expression was observed in 130 (90.3%) out of all cases, whereas pRB expression was not observed in 11 out of the 12 patients with p16-positive tumors. A negative correlation was also found between p16 and pRB (P < 0.0001). A positive correlation was noted between pRB and Cyclin D1 expression (P=0.0009). The cumulative survival rate of patients without pRB expression was significantly lower than that of patients with positive expression (P=0.003). In the multivariate survival analysis, pRB expression was an independent prognostic factor. In 98% of all patients with esophageal cancer, impairment of the G1 checkpoint is due to a loss of function by p16, pRB or Cyclin D1, which showed a negative correlation in each factor. In addition, aberrant expression of pRB is useful as a prognostic factor in esophageal cancer.
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PMID:Cell cycle-regulated factors in esophageal cancer. 1222 Apr 23

Glycogen synthase kinase-3beta-dependent phosphorylation of cyclin D1 at a conserved COOH-terminal residue, Thr-286, promotes CRM1-dependent cyclin D1 nuclear export at the G(1)-S boundary. Mutations that perturb the phosphorylation of cyclin D1 at Thr-286 contribute to cell transformation, although to date, no such mutations have been found in human cancers. Cyclin D1 (CCND1) undergoes alternative splicing leading to the production of an mRNA predicted to encode a unique cyclin D1 isoform, cyclin D1b, which lacks Thr-286. We have cloned and expressed cyclin D1b, and find that it retains the ability to bind to and activate CDK4. Unlike canonical cyclin D1a, cyclin D1b remains nuclear through the cell cycle where its constitutive expression facilitates cellular transformation. Using antisera specific for cyclin D1b, the protein was detected in a high percentage of esophageal cancer-derived cell lines and in primary esophageal carcinomas. Therefore, alternative splicing leads to expression of a nuclear, oncogenic cyclin D1 isoform that is expressed in human cancer.
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PMID:An alternatively spliced cyclin D1 isoform, cyclin D1b, is a nuclear oncogene. 1461 95

Squamous cancers of the oral cavity and esophagus are common worldwide. A number of environmental factors as well as genetic alterations have been identified. However, the specific combination of genetic events and their interplay with environmental carcinogens are largely un-known. Furthermore, no good animal model existed to study the molecular changes important in the induction and progression of the disease. Here we summarize the efforts made to establish a mouse model of oral-esophageal carcinogenesis. Cyclin D1 overexpressing(L2D1+) mice were generated using an EBV promoter to specifically target the oral cavity and the esophageal squamous epithelium. Besides analyzing different environmental factors, such as nitrosamines and zinc deficiency, cyclin D1 transgenic mice were crossbred with p53-deficient mice. While L2D1+ mice exhibited a phenotype of dysplasia, different combinations of mice result-ed in invasive oral-esophageal cancer. This mouse model provides a well-defined and reproducible model of oral-esophageal cancer that should be useful for testing chemopreventive, diagnostic, and therapeutic strategies.
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PMID:A mouse model of oral-esophageal carcinogenesis. 1569 43

Although cyclin D1 is overexpressed in a significant number of human cancers, overexpression alone is insufficient to promote tumorigenesis. In vitro studies have revealed that inhibition of cyclin D1 nuclear export unmasks its neoplastic potential. Cyclin D1 nuclear export depends upon phosphorylation of a C-terminal residue, threonine 286, (Thr-286) which in turn promotes association with the nuclear exportin, CRM1. Mutation of Thr-286 to a non-phosphorylatable residue results in a constitutively nuclear cyclin D1 protein with significantly increased oncogenic potential. To determine whether cyclin D1 is subject to mutations that inhibit its nuclear export in human cancer, we have sequenced exon 5 of cyclin D1 in primary esophageal carcinoma samples and in cell lines derived from esophageal cancer. Our work reveals that cyclin D1 is subject to mutations in primary human cancer. The mutations identified specifically disrupt phosphorylation of cyclin D1 at Thr-286, thereby enforcing nuclear accumulation of cyclin D1. Through characterization of these mutants, we also define an acidic residue within the C-terminus of cyclin D1 that is necessary for recognition and phosphorylation of cyclin D1 by glycogen synthase kinase-3 beta. Finally, through construction of compound mutants, we demonstrate that cell transformation by the cancer-derived cyclin D1 alleles correlates with their ability to associate with and activate CDK4. Our data reveal that cyclin D1 is subject to mutations in primary human cancer that specifically disrupt phosphorylation-dependent nuclear export of cyclin D1 and suggest that such mutations contribute to the genesis and progression of neoplastic growth.
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PMID:Identification of mutations that disrupt phosphorylation-dependent nuclear export of cyclin D1. 1673 30


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