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1.
We have examined the correlation of a frequent A/G polymorphism within exon 4 of the cyclin D1 gene (CCND1) with genetic susceptibility and clinical outcome in 384 patients with squamous cell carcinoma (SCC) of the head and neck. CCND1 genotype frequencies were similar in the cases and 191 controls. Furthermore, the CCND1 genotype was not associated with susceptibility to SCC of the larynx, pharynx, or oral cavity. The influence of the CCND1 genotype on clinical outcome was also assessed. We found no correlation between genotype and tumor size (T1-T4), the involvement of nodes at presentation, or patient age and gender. However, the distribution of CCND1 genotypes in cases with poorly differentiated tumors was significantly different to that in patients with well-/moderately differentiated tumors (P = 0.016; chi2(2) = 8.71). Homozygosity for CCND1*G (GG genotype) was associated with poorly differentiated tumors (G3). We used Cox's proportional hazards model to investigate the influence of the CCND1 genotype on disease-free interval. CCND1 GG was associated with reduced disease-free interval [P = 0.001; hazard ratio (HR) = 2.95; 95% confidence interval (CI) = 1.54-5.63]. This remained significant after correction for tumor differentiation (P = 0.013; HR = 2.34; 95% CI = 1.2-4.6) and tumor stage (P = 0.005; HR = 2.64; 95% CI = 1.34-5.19). Analysis of the data from patients with tumors at different sites showed that the CCND1 GG genotype was associated with reduced disease-free interval in laryngeal (P = 0.004; HR = 3.63; 95% CI = 1.44-8.83) and pharyngeal (P = 0.006; HR = 3.48; 95% CI = 1.43-8.46) tumors. This is the first report of an association between CCND1 polymorphism and prognosis in SCC of the head and neck. These data show that the CCND1 GG genotype is an independent prognostic indicator of disease-free interval and supports initial observations in non-small cell lung cancer, that polymorphism within CCND1 influences tumor behavior.  相似文献   

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The deregulation of cyclin D1 (BCL-1, PRAD1, CCND1) protein, normally synthesized in the G1 phase of the cell cycle, has been implicated in the pathogenesis of some malignant neoplasms, including invasive mammary carcinomas. We used rabbit polyclonal antibody 19 to detect cyclin D1 in 55 infiltrating ductal carcinomas and compared the findings to six important clinicopathologic parameters and cyclin D1 gene amplification. Nuclear immunoreactivity of variable intensity for cyclin D1 was present in 35% of the neoplasms, whereas immunoreactivity of normal mammary epithelial nuclei was absent. No significant correlations were observed between immunoreactivity and patient age, axillary lymph node status, estrogen receptors, progesterone receptors, histologic grade, or any of its three components. There was a correlation between cyclin D1 immunostaining and tumor size (P = 0.013). Fourteen of 15 tumors 2 cm or less were negative, whereas 7 of 12 neoplasms larger than 4 cm were immunopositive. Fifteen percent of the invasive carcinomas had cyclin D1 gene amplification. Of these eight tumors, six showed cyclin D1 immunoreactivity (P = 0.017). In this study, cyclin D1 was detected immunohistochemically in approximately one-third of infiltrating ductal carcinomas; approximately one-third of these had detectable cyclin D1 gene amplification. These results further implicate cyclin D1 in breast tumorigenesis and are additional evidence for the role of cell cycle regulatory proteins in invasive mammary carcinoma.  相似文献   

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We have shown previously that normal B cells share, with Epstein-Barr virus-transformed and malignant B cells, the ability to activate the alternative pathway (AP) of complement in vitro, resulting in the deposition of C3 fragments on the cell surface. Complement receptor type 2 (CR2, CD21) has been implicated directly as the site for formation of an AP convertase, which provides nascent C3b for deposition at secondary sites on the B-cell surface. In the present study, we have examined C3 fragment deposition in vitro in more detail by (1) assessing the importance of locally generated C3b for the deposition process, (2) investigating whether CR2 is the sole requirement for conferring AP activation capacity on a cell, and (3) determining whether CR2's function, as an AP activator, has different structural requirements from ligand binding. Increasing the availability of native C3, by increasing the serum (NHS) concentration, resulted in enhanced C3 fragment deposition on the B cells, whereas use of factor 1-depleted NHS, which showed massive fluid phase C3 conversion during the incubation, diminished the deposition. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and Western blotting of untreated and hydroxylamine-treated lysates from B cells, after in vitro activation, revealed that the majority of C3 fragments (primarily iC3b and C3dg) had been covalently bound to the cell surface. Transfection of COS cells with wild-type CR2 or a deletion mutant lacking 11 of the molecule's 15 homologous domains, but retaining the ligand-binding site, revealed that expression of intact CR2 conferred a 12-fold increase in AP-activating capacity on these cells, while no increase in AP activity was apparent on cells transfected with the mutant CR2.  相似文献   

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The EMS1 and CCND1 genes at chromosome 11q13 are amplified in about 15% of primary breast cancers but appear to confer different phenotypes in ER positive and ER negative tumours. Since there are no published data on EMS1 expression in large series of breast cancers we examined the relationship of EMS1 expression with EMS1 gene copy number and expression of mRNAs for cyclin D1 and ER. In a subset of 129 patients, where matched tumour RNA and DNA was available, EMS1 mRNA overexpression was associated predominantly with gene amplification (P = 0.0061), whereas cyclin D1 mRNA overexpression was not (P = 0.3142). In a more extensive series of 351 breast cancers, there was no correlation between cyclin D1 and EMS1 expression in the EMS1 and cyclin D1 overexpressors (P = 0.3503). Although an association between EMS1 mRNA expression and ER positivity was evident (P = 0.0232), when the samples were divided into quartiles of EMS1 or cyclin D1 mRNA expression, the increase in the proportion of ER positive tumours in the ascending EMS1 mRNA quartiles was not statistically significant (P = 0.0951). In marked contrast there was a significant stepwise increase in ER positivity in ascending quartiles of cyclin D1 mRNA (P = 0.030). A potential explanation for this difference was provided by the observation that in ER positive breast cancer cells oestradiol treatment resulted in increased cyclin D1 gene expression but was without effect on EMS1. The relationship between EMS1 expression and clinical outcome was examined in a subset of 234 patients with median follow-up of 74 months. High EMS1 expression was associated with age > 50 years (P = 0.0001), postmenopausal status (P = 0.0008), lymph node negativity (P = 0.019) and an apparent trend for worse prognosis in the ER negative subgroup. These data demonstrate that overexpression of EMS1 mRNA is largely due to EMS1 gene amplification, is independent of cyclin D1 and ER expression and, in contrast to cyclin D1, is not regulated by oestrogen. Independent overexpression of these genes may confer different phenotypes and disease outcomes in breast cancer as has been inferred from recent studies of EMS1 and CCND1 gene amplification.  相似文献   

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p21(Waf1/Cipl) is a critical downstream effector in the p53-dependent pathway of growth control and causes growth arrest through inhibition of cyclin-dependent kinases. In this study 67% of 43 head and neck squamous cell carcinoma (HNSCC) and 60% of 15 tumour-adjacent oral dysplasias overexpressed p21 by immunohistochemical staining. Overexpression of p21 in HNSCC was independent of the presence of functional p53, as assessed by analysis of mutations and loss of heterozygosity and by immunohistochemisty. Rather, the expression pattern of p21 was associated with differentiation. Furthermore, in most tumours, the p21 positive cells did not incorporate bromodeoxyuridine (BrdU), which indicates inhibition of proliferation by p21 in these cells. In some tumours, p21 was also expressed in proliferating cells. In these latter tumour cells, cyclin D1 was frequently expressed as well. Therefore, we suggest that expression of cyclin D1 might overcome the inhibitory effect of p21 in these cells.  相似文献   

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Cyclin D1 is a cell cycle regulator essential for G1 phase progression and is frequently overexpressed in several human tumour types as a consequence of gene amplification or chromosomal rearrangements. We analysed the expression of cyclin D1 in 75 patients with transitional cell carcinoma (TCC) to investigate the possible relationship between its expression and clinical outcome as well as histopathological findings using the immunohistochemical method. We observed strong staining (++, > 50% positive cells) for cyclin D1 in 19 cases (25.3%) and weak staining (+, 5-50% positive cells) in 19 cases (25.3%). Overexpression of cyclin D1 was not associated with tumour invasion. No significant association was found between overexpression of cyclin D1 and tumour grade (P > 0.05). We assessed the differences of disease-free interval in superficial tumours and actuarial survival probability in invasive tumours according to the status of cyclin D1 expression. Tumours with (++) staining for cyclin D1 recurred much more rapidly than (-) and/or (+) staining tumours (P < 0.01 for - vs ++; P < 0.05 for + vs ++). However, overexpression of cyclin D1 was not associated with a shortened overall survival of patients with invasive tumours (P < 0.1). These results suggest that genetic alteration of cyclin D1 appears to be an early event in the tumorigenesis of bladder TCC and is associated with early recurrence in superficial tumours.  相似文献   

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Using a polymorphic dinucleotide repeat, we have investigated the contribution of the gene encoding the beta-subunit of the muscle acetylcholine receptor (CHRNB1), the target autoantigen, to the susceptibility to myasthenia gravis (MG). We have combined a case-control study (comparing 143 patients and 162 controls) and a transmission-disequilibrium test bearing on 35 simplex families with heterozygous parents. There was no evidence for an association of CHRNB1 with MG, even after subgrouping patients according to thymus histology, or other clinical criteria. Interestingly however, the shortest four variants of the CHRNB1 microsatellite were seen only in patients with thymus hyperplasia and in none of the control subjects (P < 0.0025).  相似文献   

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Activating mutations in the c-K-ras gene occur in about 40% of human colorectal carcinomas, yet the role of this oncogene in tumorigenesis is not known. We have developed a model cell culture system to study this problem, utilizing the immortalized but non-tumorigenic epithelial cell line IEC18, originally derived from normal rat intestine epithelium. These cells were cotransfected with the drug resistance selectable marker tk-neo and the plasmid pMIKcys, which encodes a mini human c-K-ras gene (15 kb) containing a cysteine mutation at codon 12. Drug resistant clones were isolated. Clones which also expressed the activated c-K-ras gene displayed a transformed morphology, decreased doubling time, increased level of diacylglycerol, anchorage independent growth in soft agar and an aneuploid karyotype and they were also tumorigenic when injected into nude mice. These clones also displayed increased expression, at both the mRNA and protein levels, of cyclin D1 and Rb. These findings may be of clinical relevance since human colorectal tumors also frequently display increased expression of both cyclin D1 and Rb. This model system may be useful for understanding the role and interrelationship between activation of the c-K-ras oncogene and increased expression of cyclin D1 and Rb in colorectal tumorigenesis.  相似文献   

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BACKGROUND: Interventional magnetic resonance (MR) imaging allows neurosurgeons to interactively perform surgery using MR guidance. High-field (1.5-Tesla) strength imaging provides exceptional visualization of intracranial and spinal pathology. The full capabilities of this technology for pediatric neurosurgery have not been defined or determined. MATERIALS AND METHODS: From January 1997 through June 1998, 10 of 85 cases performed in the interventional MR unit were in the pediatric population (mean age 8.3, median 8, range 2-15 years). Procedures included 2 brain biopsies, 5 craniotomies for tumor, 2 thoracic laminectomies for syringomyelia, and placement of a reservoir into a cystic brainstem tumor. The biopsies and reservoir placement were performed using MR-compatible equipment. Craniotomies and spinal surgery were performed with conventional instrumentation outside the 5-Gauss magnetic footprint. Interactive and intraoperative imaging was performed to assess the goals of surgery. RESULTS: Both brain biopsies were diagnostic for cerebral infarct and anaplastic astrocytoma and the reservoir was optimally placed within the tumor cyst. Of the 5 tumor resections, all were considered radiographically complete. One biopsy patient and 1 tumor resection patient experienced transient neurological deficits after surgery. The patient with the thoracic syrinx required reoperation when the syringosubarachnoid shunt migrated into the syrinx 3 months after initial placement. No patient sustained a postoperative hemorrhage. Tumor histologies found at craniotomy were craniopharyngioma, ganglioglioma, and 3 low-grade gliomas. No evidence of tumor progression has been seen in any of these patients at a mean follow-up of 5.3 (range 4-8) months. The goals of the procedure were achieved in all 10 cases. There were no untoward events experienced related to MR-compatible instrumentation or intraoperative patient monitoring, despite the present inability to monitor core body temperature. CONCLUSIONS: 1.5-Tesla interventional MR is a safe and effective technology for assisting neurosurgeons to achieve the goals of pediatric neurosurgery. Preliminary results suggest that surgical resection of histologically benign tumors is enhanced in the interventional MR unit. The incidence of surgically related morbidity is low.  相似文献   

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One way to explain the development of head and neck cancer is through the theories of field cancerization, i.e., the exposure of an entire field of tissue to repeated carcinogenic insult, and multistep process, i.e., development of multiple cancers in a predisposed filed through a series of recognizable stages. Recent molecular genetic studies of histologically normal and premalignant epithelia of high-risk subjects and studies of malignant tumors in aerodigestive tract epithelia have identified a continuum of accumulated specific genetic alterations that possibly occur during the clonal evolution of tumors, namely, during the multistep process. Second primary or multiple primary tumors arise in the same fields as independent clones, with similar but unique molecular genetic and/or cellular alterations. Consequently, the assessment of these genetic and phenotypic alterations has been integrated into clinical chemoprevention trials in an effort to identify biomarkers that are also risk predictors and intermediate end points. This review covers candidate biomarkers of the processes of field cancerization and multistep tumor development in aerodigestive tract epithelia, including general and specific genetic markers, proliferation markers, and squamous differentiation markers.  相似文献   

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Multiple sclerosis (MS) is known to be associated with HLA-DR2, but it is possible that additional major histocompatibility complex (MHC) genes confer disease susceptibility. The most recent candidate genes for MHC-encoded susceptibility are the TAP genes, which are located between the HLA-DQ and DP loci, and encode for proteins believed to transport antigenic peptides from the cytoplasm into the endoplasmic reticulum. We studied TAP 1 and TAP 2 gene polymorphisms in 65 chronic progressive MS patients and 66 healthy subjects. No significant differences in the frequencies of TAP polymorphisms were observed between both groups. These data suggest that TAP is not a susceptibility gene for MS and that the disease-predisposing haplotype does not extend as far as TAP.  相似文献   

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Recent evidence suggests that neuronal apoptosis is the consequence of an inappropriate reentry into the cell cycle. Expression of the cell cycle gene cyclin D1, a G1-phase cell cycle regulator, was examined in primary cultures of murine cerebellar granule cells (CGCs) during kainate (KA)-mediated apoptosis. Using cultures of CGCs, we found that a 24-h exposure to KA (1-3,000 microM) induced a concentration-dependent cell death with neurons exhibiting characteristic apoptotic morphology and extensive labeling using the terminal transferase-mediated nick end-DNA labeling (TUNEL) method. KA induced a time- and concentration-dependent increase in expression of cyclin D1 as determined by immunocytochemistry and western blot analysis. KA-induced apoptosis and cyclin D1 expression exhibited a similar concentration dependence and were significantly attenuated by the non-NMDA receptor antagonist 6-cyano-7-nitroquinoxaline-2,3-dione (50 microM), indicating a KA receptor-mediated effect. Here we present evidence for the first time that KA-induced apoptosis in cultured CGCs involves the induction of cyclin D1, suggesting its involvement in excitotoxic receptor-mediated apoptosis.  相似文献   

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The organotypic (raft) culture system has been shown to be a useful model for examining the effects of biochemical manipulations on various epithelial cell types, using in vitro conditions that simulate the in vivo environment of the tissue of origin. To investigate this method as a model for topical gene therapy, we cultured the oral head and neck squamous cell carcinoma cell line TR146 on fibroblast-containing collagen gels at the air-medium interface and assessed the efficiency of transduction of a topically applied adenoviral vector containing beta-galactosidase cDNA. Diffuse expression of -galactosidase activity in multiple cell layers demonstrated effective penetration of the vector. Transduction efficiency and therapeutic activity of a replication-defective recombinant adenovirus containing wild-type p53 cDNA linked to a FLAG marker (AdCMV-p53-FLAG) were then assessed in TR146 organotypic cultures transduced by topical application. Twenty-four, 48, and 72 h after transduction, the cultures were harvested, and residual cell number and FLAG peptide expression were determined. The number of cells in p53 transduced cultures was significantly reduced in comparison to controls at all three time points (P < 0.001), which resulted from the induction of apoptosis as determined by in situ DNA end labeling. In addition, the FLAG peptide was expressed diffusely in the residual cells, further confirming effective transduction and expression of the exogenous gene products throughout multiple layers. We conclude that the organotypic culture is an effective in vitro model for assessing the efficacy of topically applied gene therapy on head and neck squamous carcinomas and premalignancies.  相似文献   

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BACKGROUND: Experimental and clinical studies suggest that cyclin D1 is involved in transformation and tumour progression. However, there is little and contradictory data on the clinical significance of cyclin D1 in human invasive breast carcinoma. PATIENTS AND METHODS: We investigated whether the determination of cyclin D1 has prognostic value in a series of 180 patients with node-positive breast carcinoma and treated with adjuvant therapy with a median follow-up exceeding 6 years. We assessed cyclin D1 expression using the CDS-6 monoclonal antibody and a highly sensitive immunohistochemical technique. RESULTS: We found that most of the evaluable tumours (117 of 167; 70.1%) presented nuclear cyclin D1 staining and that its expression was significantly associated with both the hormone receptors (P = 0.009 and P = 0.005 for ER and PgR, respectively). Furthermore, 29 (17%) of 167 tumours had a weak (15 cases) or strong (9 cases) cytoplasmic cyclin D1 staining. In a subgroup of cases we also studied the amplification of the cyclin D1 gene and a moderate agreement between cyclin D1 nuclear overexpression assessed immunohistochemically and the gene amplification was found. In univariate analysis, cyclin D1 nuclear positivity was significantly associated with improved 6-year relapse-free survival (RFS) (P = 0.004), but not with overall survival (OS) (P = 0.12). The results of the Cox multivariate analysis (final model) indicate that cyclin D1 expression (P = 0.0049) as well as the number of involved nodes (P < 0.001) and tumour size (P = 0.036) are significant prognostic indicators for RFS. Only the number of involved nodes retained significance (P < 0.001) for OS in our series. The joint assessment of the variables considered in the final model of the multivariate analyses had a moderate prognostic capability as determined using the Harrell c statistic (c = 0.66 and 0.64 for RFS and OS, respectively). CONCLUSIONS: The patients with node-positive breast cancer who have a higher likelihood of gaining benefit from adjuvant therapy are those with tumours with cyclin D1 nuclear expression, small size and less than 3 metastatic nodes. Further studies are needed to verify the prognostic value of cyclin D1 in relation to different adjuvant treatments and to deepen the biological pathways that regulate its activation/ suppression in human breast carcinoma.  相似文献   

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Centrocytic lymphoma (CC) and intermediately differentiated lymphocytic lymphoma (IDL) are B-cell non-Hodgkin's lymphomas composed of lymphocytes presumably derived from follicle mantle cells. In these lymphomas, a specific chromosomal translocation, t(11;14)(q13;q32), has been described. Previous studies suggested an association between t(11;14) chromosomal translocations and BCL-1 rearrangements. To evaluate the association between BCL-1 rearrangements and CC/IDL, Southern blot analysis was performed on a panel of 20 cases of CC/IDL, 22 cases of morphologically similar non-Hodgkin's lymphomas, 11 cases of chronic B-cell leukemias, and 2 cases of myelomas. We used various probes covering a considerable proportion of the 120-kilobase BCL-1 locus, and rearrangements in 50% of CC/IDL (10 of 20) were detected. In CC, all 4 breakpoints were located at the major translocation cluster (MTC). In contrast, in IDL, rearrangements were detected in 3 different cluster regions: 2 cases in the MTC, 2 cases with a breakpoint 24 kilobases outside the MTC, and 2 additional cases with breakpoints found 3 kilobases 5' of the first exon of the PRAD1/CCND1 gene, which is located 120 kilobases outside the MTC. In addition, one leukemia showed a breakpoint 63 kilobases outside the MTC. In all cases, there was comigration of the rearranged 11q13 fragment and the immunoglobulin heavy chain-joining gene complex, indicating a t(11;14)(q13;q32) chromosomal rearrangement. Our results show that Southern blot analysis is helpful to identify CC/IDL, but multiple breakpoints are present over a large region, and therefore, many probes are necessary to cover all breakpoints.  相似文献   

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