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101.
In this study expression of protein kinase C alpha (PKCalpha), delta (PKCdelta) and iota (PKCiota) was determined immunohistochemically in formalin-fixed paraffin-embedded tissue specimen of ovarian cystadenomas (n=7), borderline tumours of the ovary (n=8), primary (n=54) and recurrent invasive ovarian carcinomas (n=13). The expression was correlated with clinicopathological parameters and patient survival. In addition, expression of PKCiota was assessed in 3 ovarian carcinoma cell lines (OVCAR-3, SKOV-3, OAW-42) and in one human ovarian surface epithelium (HOSE) cell line. We found expression of PKCalpha in 71.4% of cystadenomas, 50% of borderline tumours, 53.7% of primary and 38.5% of recurrent ovarian carcinomas. PKCdelta was not expressed in epithelium of adenomas, borderline tumours, primary and recurrent ovarian carcinomas. PKCiota was expressed in 51.9% of primary and 46.2% of recurrent ovarian carcinomas but not in cystadenomas and borderline tumours of the ovary. Consistent with these findings ovarian carcinoma cell lines showed strong expression of PKCiota whereas HOSE cells did not. Correlation of PKCalpha and PKCiota expression and clinicopathological features revealed a significant negative correlation of PKCalpha with histopathological grading and a significant positive correlation of PKCiota with histopathological grading and FIGO stage as well as a borderline significant positive correlation with proliferation index. Univariate survival analysis showed that amongst other yet known prognostic parameters (FIGO stage, histopathological grading, proliferation index) PKCiota expression in primary ovarian carcinomas correlated significantly (p=0.024) with a reduced median survival time, but was not an independent prognostic factor. The findings of this study, together with data from functional studies by other groups suggest that alteration of PKC isoform expression may be involved in progression of ovarian carcinomas.  相似文献   
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103.
PURPOSE: The human ELAV (embryonic lethal abnormal vision)-like protein HuR stabilizes a certain group of cellular mRNAs that contain AU-rich elements in their 3'-untranslated region. Cell culture studies have shown that the mRNA of cyclooxygenase (COX)-2 can be stabilized by HuR. EXPERIMENTAL DESIGN: To investigate a possible contribution of dysregulation of mRNA stability to the progression of cancer and to overexpression of COX-2, we studied expression of HuR in 208 primary breast carcinomas by immunohistochemistry. RESULTS: There were two different staining patterns of HuR in tumor tissue of breast carcinomas: nuclear expression was seen in 61% of cases; and an additional cytoplasmic expression was seen in 30% of cases. Expression of HuR was significantly associated with increased COX-2 expression; this association was particularly significant for cytoplasmic HuR expression (P < 0.0005). We further observed a significant association of cytoplasmic (P = 0.002) or nuclear HuR (P = 0.027) expression with increased tumor grade. Only 13% of the grade 1 carcinomas showed cytoplasmic expression of HuR, compared with 46% of the grade 3 carcinomas. There was no significant correlation between HuR expression and other clinicopathological parameters such as histological type, tumor size, or nodal status as well as patient survival. CONCLUSIONS: Our results suggest that overexpression of HuR in tumor tissue may be part of a regulatory pathway that controls the mRNA stability of several important targets in tumor biology, such as COX-2. Based on our results, additional studies are necessary to investigate whether HuR might be a potential target for molecular tumor therapy.  相似文献   
104.

Background

It is unknown whether an unfavorable (atherogenic) lipid profile and homocysteine level, which could supersede clinical cardiovascular disease, is also associated with an increased risk of spontaneous preterm delivery (sPTD). A systematic review of studies assessing the lipid profile and homocysteine value of women with sPTD compared to women with term delivery in pre-pregnancy and during pregnancy.

Methods

A systematic search of peer-reviewed articles published between January 1980 and May 2014 was performed using MEDLINE, EMBASE and the Cochrane database. We included case–control and cohort studies that examined triglycerides, high/low density lipoprotein cholesterol, total cholesterol and homocysteine in women with sPTD. Articles were subdivided in pre-pregnancy, first, second and third trimester. Of 708 articles reviewed for eligibility, 14 met our inclusion criteria.

Results and conclusion

Nine cohort studies and five case–control studies were analyzed, reporting on 1466 cases with sPTD and 11296 controls with term delivery. The studies suggest a possible elevated risk of sPTD in woman with high TG levels, no association of high and low density lipoprotein cholesterol with the risk of sPTD was found. High homocysteine levels are associated with sPTD in the second trimester. The role of triglycerides and homocysteine in sPTD should be explored further.
  相似文献   
105.
Clinical trials indicate efficacy of drugs inhibiting the mammalian target of rapamycin (mTOR) in the treatment of gastroenteropancreatic neuroendocrine tumours (GEP-NET); however, information on detailed expression and activity patterns of mTOR in these tumours is sparse. We investigated the expression of mTOR and expression as well as phosphorylation of its downstream targets 4EBP1, S6K and eIF4E in a cohort of 99 human GEP-NET by immunohistochemistry. We correlated our findings with clinicopathological variables and patient prognosis. We found that 61, 93, 80, 69, 57 and 79% of GEP-NET were positive for mTOR, 4EBP1, cytoplasmic phospho-4EBP1 (p-4EBP1), nuclear p-4EBP1, phospho-S6K (p-S6K) and phospho-eIF4E (p-eIF4E) respectively. mTOR expression and activity were higher in foregut than in midgut tumours. In foregut tumours, expression of mTOR was higher when distant metastases were present (P=0.035). Strong mTOR activity was associated with higher proliferative capacity. In patients with stage IV midgut tumours, strong p-S6K expression was associated with poor disease-specific survival (P=0.048). In conclusion, mTOR shows considerable variations in expression and activity patterns in GEP-NET in dependence of tumour location and metastatic status. We hypothesise that these differences in mTOR expression and activity might possibly influence response to mTOR inhibitors.  相似文献   
106.
107.
Ovarian carcinoma has the highest mortality rate among gynaecological malignancies. In this project, we investigated the hypothesis that molecular markers are able to predict outcome of ovarian cancer independently of classical clinical predictors, and that these molecular markers can be validated using independent data sets. We applied a semi‐supervised method for prediction of patient survival. Microarrays from a cohort of 80 ovarian carcinomas (TOC cohort) were used for the development of a predictive model, which was then evaluated in an entirely independent cohort of 118 carcinomas (Duke cohort). A 300‐gene ovarian prognostic index (OPI) was generated and validated in a leave‐one‐out approach in the TOC cohort (Kaplan‐Meier analysis, p = 0.0087). In a second validation step, the prognostic power of the OPI was confirmed in an independent data set (Duke cohort, p = 0.0063). In multivariate analysis, the OPI was independent of the post‐operative residual tumour, the main clinico‐pathological prognostic parameter with an adjusted hazard ratio of 6.4 (TOC cohort, CI 1.8–23.5, p = 0.0049) and 1.9 (Duke cohort, CI 1.2–3.0, p = 0.0068). We constructed a combined score of molecular data (OPI) and clinical parameters (residual tumour), which was able to define patient groups with highly significant differences in survival. The integrated analysis of gene expression data as well as residual tumour can be used for optimized assessment of the prognosis of platinum‐taxol‐treated ovarian cancer. As traditional treatment options are limited, this analysis may be able to optimize clinical management and to identify those patients who would be candidates for new therapeutic strategies. Copyright © 2009 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.  相似文献   
108.
109.
To live a self-determined life at home is uncontroversally a desire of many ageing people. Decreases in motor and mental capabilities, however, frequently make daily activities more difficult for them. Older people often forget tasks and appointments, and decreased mobility can limit their social interaction. In this study, we investigate the way in which technological support can assist in the organisation, structuring and remembering of daily activities. Aiming at assistance seamlessly integrated into a person's household, we carried out an initial user study to investigate the technology and the kind of desired assistance of such a personal household assistant system should offer. We designed a reminder system for appointments and activities that uses different sounds, light colours or vibration patterns to represent different categories of calendar events such as upcoming tasks and appointments. The evaluation results show a preference for solely acoustic presentations or an acoustic presentation in combination with visual and tactile output. In our future work, we will refine the ambient and interactive presentation and implement and evaluate this technology in residential homes.  相似文献   
110.
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