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41.
Germline mutations in the fumarate hydratase (FH) gene at 1q43 predispose to dominantly inherited cutaneous and uterine leiomyomas, uterine leiomyosarcoma, and papillary renal cell cancer (HLRCC syndrome). To evaluate the role of FH inactivation in sporadic tumorigenesis, we analyzed a series of 299 malignant tumors representing 10 different malignant tumor types for FH mutations. Additionally, 153 uterine leiomyomas from 46 unselected individuals were subjected to and informative in loss of heterozygosity analysis at the FH locus, and the five (3.3%) tumors displaying loss of heterozygosity were subjected to FH mutation analysis. Although mutation search in the 299 malignant tumors was negative, somatic FH mutations were found in two nonsyndromic leiomyomas; a splice site change IVS4 + 3A>G, leading to deletion of exon four, and a missense mutation Ala196Thr. The occurrence of somatic mutations strongly suggests that FH is a true target of the 1q43 deletions. Although uterine leiomyomas are the most common tumors of women, specific inactivating somatic mutations contributing to the formation of nonsyndromic leiomyomas have not been reported previously. Taking into account the apparent risk of uterine leiomyosarcoma associated with FH germline mutations, the finding raises the possibility that also some nonsyndromic leiomyomas may have a genetic profile that is more prone to malignant degeneration. Our data also indicate that somatic FH mutations appear to be limited to tumor types observed in hereditary leiomyomatosis and renal cell cancer.  相似文献   
42.
Previous studies in asthmatic subjects and guinea pigs have demonstrated attenuation of bronchoconstriction in repeated exposures to clean cold dry air. In the present animal study, we have simulated short-lasting human exposures to subfreezing urban air containing sulfur dioxide (SO2) and nitrogen dioxide (NO2). The anesthetized, paralyzed, and mechanically ventilated guinea pigs had 4 consecutive 10-min exposures either to clean cold dry air or to cold air with graded concentrations of SO2 (0-5 ppm) or NO2 (0-4 ppm). Peak expiratory flow (PEF) and tidal volume (VT  相似文献   
43.
The multiple molecular alterations underlying the neoplastic process and clinical characteristics of cutaneous melanoma are currently under intensive investigation. Recent studies have demonstrated that the levels of melanoma-associated proteins in tumor tissue or in patient serum can serve as new markers to predict disease outcome. Similarly, the expression of thousands of genes in melanoma tumors can be surveyed simultaneously using DNA arrays, allowing molecular profiling of individual tumors, which gives the possibility of classifying melanomas based on their biological diversity. Large clinical studies have also identified multiple prognostic factors, such as tumor ulceration, and led to development of a new, more precise melanoma staging system, which emphasizes the biological characteristics of the primary disease. These new findings may have an important role in earlier measurement of the clinical response and provide a basis for tailored melanoma therapy, the development of which will also be discussed in this review.  相似文献   
44.
Prediction of the clinical outcome of breast cancer is multi-faceted and challenging. There is growing evidence that the complexity of the tumour micro-environment, consisting of several cell types and a complex mixture of proteins, plays an important role in development, progression, and response to therapy. In the current study, we investigated whether invasive breast tumours can be classified on the basis of the expression of extracellular matrix (ECM) components and whether such classification is representative of different clinical outcomes. We first examined the matrix composition of 28 primary breast carcinomas by morphology and gene expression profiling using 22K oligonucleotide Agilent microarrays. Hierarchical clustering of the gene expression profile of 278 ECM-related genes derived from the literature divided the tumours into four main groups (ECM1-4). A set of selected differentially expressed genes was validated by immunohistochemistry. The robustness of the ECM classification was confirmed by studying the four ECM groups in a previously published gene expression data set of 114 early-stage primary breast carcinomas profiled using cDNA arrays. Univariate survival analysis showed significant differences in clinical outcome among the various ECM subclasses. One set of tumours, designated ECM4, had a favourable outcome and was defined by the overexpression of a set of protease inhibitors belonging to the serpin family, while tumours with an ECM1 signature had a poorer prognosis and showed high expression of integrins and metallopeptidases, and low expression of several laminin chains. Furthermore, we identified three surrogate markers of ECM1 tumours: MARCO, PUNC, and SPARC, whose expression levels were associated with breast cancer survival and risk of recurrence. Our findings suggest that primary breast tumours can be classified based upon ECM composition and that this classification provides relevant information on the biology of breast carcinomas, further supporting the hypothesis that clinical outcome is strongly related to stromal characteristics.  相似文献   
45.
Breast cancer is the most common cancer in women in developed countries and has a well-established genetic component. Germline mutations in a network of genes encoding BRCA1, BRCA2, and their interacting partners confer hereditary susceptibility to breast cancer. Abraxas directly interacts with the BRCA1 BRCT (BRCA1 carboxyl-terminal) repeats and contributes to BRCA1-dependent DNA damage responses, making Abraxas a candidate for yet unexplained disease susceptibility. Here, we have screened 125 Northern Finnish breast cancer families for coding region and splice-site Abraxas mutations and genotyped three tagging single-nucleotide polymorphisms within the gene from 991 unselected breast cancer cases and 868 female controls for common cancer-associated variants. A novel heterozygous alteration, c.1082G>A (Arg361Gln), that results in abrogated nuclear localization and DNA response activities was identified in three breast cancer families and in one additional familial case from an unselected breast cancer cohort, but not in healthy controls (P = 0.002). On the basis of its exclusive occurrence in familial cancers, disease cosegregation, evolutionary conservation, and disruption of critical BRCA1 functions, the recurrent Abraxas c.1082G>A mutation connects to cancer predisposition. These findings contribute to the concept of a BRCA-centered tumor suppressor network and provide the identity of Abraxas as a new breast cancer susceptibility gene.  相似文献   
46.
Recent genome-wide association studies identified 11 single nucleotide polymorphisms (SNPs) associated with breast cancer (BC) risk. We investigated these and 62 other SNPs for their prognostic relevance. Confirmed BC risk SNPs rs17468277 (CASP8), rs1982073 (TGFB1), rs2981582 (FGFR2), rs13281615 (8q24), rs3817198 (LSP1), rs889312 (MAP3K1), rs3803662 (TOX3), rs13387042 (2q35), rs4973768 (SLC4A7), rs6504950 (COX11) and rs10941679 (5p12) were genotyped for 25 853 BC patients with the available follow-up; 62 other SNPs, which have been suggested as BC risk SNPs by a GWAS or as candidate SNPs from individual studies, were genotyped for replication purposes in subsets of these patients. Cox proportional hazard models were used to test the association of these SNPs with overall survival (OS) and BC-specific survival (BCS). For the confirmed loci, we performed an accessory analysis of publicly available gene expression data and the prognosis in a different patient group. One of the 11 SNPs, rs3803662 (TOX3) and none of the 62 candidate/GWAS SNPs were associated with OS and/or BCS at P<0.01. The genotypic-specific survival for rs3803662 suggested a recessive mode of action [hazard ratio (HR) of rare homozygous carriers=1.21; 95% CI: 1.09-1.35, P=0.0002 and HR=1.29; 95% CI: 1.12-1.47, P=0.0003 for OS and BCS, respectively]. This association was seen similarly in all analyzed tumor subgroups defined by nodal status, tumor size, grade and estrogen receptor. Breast tumor expression of these genes was not associated with prognosis. With the exception of rs3803662 (TOX3), there was no evidence that any of the SNPs associated with BC susceptibility were associated with the BC survival. Survival may be influenced by a distinct set of germline variants from those influencing susceptibility.  相似文献   
47.
48.
OBJECTIVES: This study was conducted to evaluate the effect of grinding and sandblasting on the microstructure, biaxial flexural strength and reliability of two yttria stabilized tetragonal zirconia (Y-TZP) ceramics. METHODS: Two Y-TZP powders were used to produce fine grained and coarse grained microstructures. Sixty discs from each material were randomly divided into six groups of ten. For each group, a different surface treatment was applied: dry grinding, wet grinding, sandblasting, dry grinding + sandblasting, sandblasting + dry grinding and a control group. Biaxial flexural strength was determined and data were analyzed using one-way ANOVA, followed by Tukey's HSD test (p < 0.05). In addition, Weibull statistics was used to analyze the variability of flexural strength. The relative amount of transformed monoclinic zirconia, corresponding transformed zone depth (TZD) and the mean critical defect size Ccr were calculated. RESULTS: There was no difference in mean strength between the as sintered fine and coarse grained Y-TZP. Significant differences (p < 0.05) were found between the control group and ground fine grained material for both wet and dry grinding. Sandblasting significantly increased the strength in fine and coarse grained materials. All surface treatment procedures reduced the Weibull modulus of Y-TZP. For both materials, the highest amount of the monoclinic phase and the largest TZD was found after sandblasting. Lower amounts of the monoclinic phase were obtained after both grinding procedures, where the highest mean critical defect size Ccr was also calculated. SIGNIFICANCE: Our results indicate that sandblasting may provide a powerful technique for strengthening Y-TZP in clinical practice. In contrast, grinding may lead to substantial strength degradation and reduced reliability of prefabricated zirconia elements, therefore, sandblasting of ground surfaces is suggested.  相似文献   
49.
Recurrent miscarriage affects 1-2% of women. In more than half of all recurrent miscarriage the cause still remains uncertain. Thrombophilia has been identified in about 50% of women with recurrent miscarriage and thromboprophylaxis has been suggested as an option of treatment. A randomised double-blind (for aspirin) multicentre trial was performed among 207 women with three or more consecutive first trimester (<13 weeks) miscarriages, two or more second trimester (13-24 weeks) miscarriages or one third trimester fetal loss combined with one first trimester miscarriage. Women were analysed for thrombophilia. After complete work-up, women were randomly allocated before seven weeks' gestation to either enoxaparin 40 mg and placebo (n=68), enoxaparin 40 mg and aspirin 100 mg (n=63) or aspirin 100 mg (n=76). The primary outcome was live-birth rate. Secondary outcomes were pregnancy complications, neonatal outcome and adverse effects. The trial was ended prematurely because of slow recruitment. A live birth rate of 71% [relative risk (RR) 1.17, 95% confidence interval (CI) 0.92-1.48] was found for enoxaparin and placebo and 65% [RR 1.08, 95% CI 0.83-1.39] for enoxaparin and aspirin when compared to aspirin alone (61%, reference group). In the whole study group the live birth rate was 65% (95% CI 58.66-71.74) for women with three or more miscarriages (n=204). No difference in pregnancy complications, neonatal outcome or adverse effects was observed. No significant difference in live birth rate was found with enoxaparin treatment versus aspirin or a combination of both versus aspirin in women with recurrent miscarriage.  相似文献   
50.
OBJECTIVE: Typically, human ovarian cancer is widely disseminated at the time of diagnosis and shows extremely poor prognosis. Experimental animal models that mimic human ovarian cancer are often incomplete when compared to the full spectrum of the human disease with regard to its histological hallmarks such as the spread of carcinoma, its ability to seed the peritoneal cavity and formation of ascites. We have established and characterized a new animal model for human ovarian cancer in nude mouse. METHODS: A new cell line SKOV-3m was injected intraperitoneally in nude mice. Mice were divided in two groups A and B, which received 1 x 10(7) and 2 x 10(7) cells, respectively. Histology, immunohistochemistry, magnetic resonance imaging and ultrasound were used to analyze tumors. RESULTS: All mice had tumors within 18 days and histologically they resembled poorly differentiated human cystadenocarcinomas with bloody ascites. Mean survival of the mice was 42+/-14 and 21+/-2 days in groups A and B, respectively. Magnetic resonance imaging and ultrasound were used to confirm the presence of tumors and to monitor their growth without sacrificing the animals. CONCLUSION: This new xenograft model accompanied by noninvasive imaging is highly reproducible and likely to be very useful in testing new treatment strategies for ovarian cancer.  相似文献   
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