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791.

Background

Anterior zone (AZ) disease is present in one-fifth of men with newly diagnosed prostate cancer and has been associated with poor pathologic features. However, anterior targeted biopsies are not a routine part of active surveillance (AS) protocols. Our purpose is to assess the utility of AZ sampling for prostate biopsy in patients undergoing surveillance for low-risk prostate cancer.

Methods

A prospective data collection of men enrolled in AS between 2006 and 2014 was performed. Patient and disease characteristics were collected, including number of positive cores and Gleason score on all diagnostic and surveillance biopsies. Progression was defined as incident Gleason > 6 in any core and/or receipt of definitive therapy including radical prostatectomy or radiotherapy. Rate of anterior disease and relationship to subsequent disease progression was assessed.

Results

A total of 85 men were included, of which 45% demonstrated progression. Median follow-up was 40 months. Among those undergoing AZ sampling at initial diagnosis, 37% presented with AZ disease. A total of 47% of men with AZ-only disease progressed, whereas 78% of men with AZ and peripheral zone disease progressed. This compares with a 39% rate of progression among men with only peripheral zone disease. Multivariable logistic regression identified increasing body mass index as a significant predictor of disease progression (odds ratio, 5.18; 95% confidence interval, 1.06-25.31; P = .04).

Conclusions

Over one-third of men enrolled in AS for low-risk prostate cancer had AZ disease on diagnostic biopsy. Progression occurred in the majority of these men. AZ sampling should be considered in biopsy surveillance strategies.  相似文献   
792.

Background

Epithelial ovarian cancer (EOC) is one of the leading causes of cancer deaths in women worldwide. Adrenomedullin (AM) is a multifunctional peptide which presents in various kinds of tumors.

Methods

In this study, we characterized the expression and function of AM in epithelial ovarian cancer using immunohistochemistry staining. Exogenous AM and small interfering RNA (siRNA) specific for AM receptor CRLR were treated to EOC cell line HO8910. Wound healing assay and flow cytometry were used to measure the migration ability and expression of integrin α5 of HO8910 cells after above treatments. Western blot was used to examine the phosphorylation of FAK and paxillin.

Results

We found that patients with high AM expression showed a higher incidence of metastasis, larger residual size of tumors after cytoreduction and shorter disease-free and overall survival time. Exogenous AM induced ovarian cancer cell migration in time- and dose- dependent manners. AM upregulated the expression of integrin α5 and phosphorylation of FAK, paxillin as well.

Conclusions

Our results suggested that AM contributed to the progression of EOC and had additional roles in EOC cell migration by activating the integrin α5β1 signaling pathway. Therefore, we presumed that AM could be a potential molecular therapeutic target for ovarian carcinoma.  相似文献   
793.
S Tejpar  H Prenen  M Mazzone 《The oncologist》2012,17(8):1039-1050
The concept of targeting new blood vessel formation, or angiogenesis, in tumors is an important advancement in cancer therapy, resulting, in part, from the development of such biologic agents as bevacizumab, a monoclonal antibody directed against vascular endothelial growth factor (VEGF)-A. The rationale for antiangiogenic therapy is based on the hypothesis that if tumors are limited in their capacity to obtain a new blood supply, so too is their capacity for growth and metastasis. Additional evidence suggests that pruning and/or "normalization" of irregular tumor vasculature and reduction of hypoxia may facilitate greater access of cytotoxic chemotherapy (CT) to the tumor. Indeed, for metastatic colorectal cancer, bevacizumab in combination with established CT regimens has efficacy superior to that of CT alone. Despite ~2-month longer progression-free and overall survival times than with CT alone, patients still progress, possibly because of alternative angiogenic "escape" pathways that emerge independent of VEGF-A, or are driven by hypoxic stress on the tumor. Other VEGF family members may contribute to resistance, and many factors that contribute to the regulation of tumor angiogenesis function as part of a complex network, existing in different concentrations and spatiotemporal gradients and producing a wide range of biologic responses. Integrating these concepts into the design and evaluation of new antiangiogenic therapies may help overcome resistance mechanisms and allow for greater efficacy over longer treatment periods.  相似文献   
794.
Cutaneous melanoma susceptibility and progression genes   总被引:1,自引:0,他引:1  
This review aims to provide an up-to-date view on our understanding of the molecular genetics of melanoma development. It gives an overview of genes (and loci) currently known to be substantially involved in melanoma predisposition and progression. Broadly, the review falls into 3 sections: genes/loci involved in melanoma susceptibility through germline mutation, tumor suppressor genes somatically mutated or deleted in melanoma, and oncogenes mutated somatically in melanoma. The main cellular pathways in which these genes are involved are summarized and discussed. From this it is evident that abberations of cell cycle regulation, DNA repair and receptor-mediated signal transduction are important for melanocytic neoplasia.  相似文献   
795.
796.
SUMMARY: In this prospective study, we found a positive relationship between the prevalence of aortic calcifications and age. Aortic calcifications at baseline were positively associated with osteoporotic fractures. In addition, progression of aortic calcifications was also positively associated with the rate of decline in BMD at lumbar spine. INTRODUCTION: The aim of this study was to analyze the relationship between the progression of abdominal aortic calcification and osteoporosis in a Spanish cohort of men and women older than 50. METHODS: Men and women (n=624) aged 50 and over underwent two lateral X-rays of thoracic and lumbar spine and a dual X-ray absorptiometry (DXA) study at lumbar spine and hip, and were followed during 4 years. Abdominal aortic calcifications were classified as absent, mild-moderate and severe. RESULTS: There was a positive relationship between the prevalence of aortic calcifications and age. In both sexes, prevalent severe aortic calcifications were positively associated with prevalent osteoporotic fractures [odds ratio (OR)=1.93 (1.02-3.65)]. The association was stronger when only vertebral fracture was considered [OR=2.45 (1.23-4.87)]. In addition, progression of aortic calcifications showed a positive association with the rate of decline in bone mineral density (BMD) at lumbar spine. CONCLUSIONS: Aortic calcifications at baseline were positively associated with osteoporotic fractures. The progression of aortic calcifications was also positively associated with the rate of decline in BMD at lumbar spine.  相似文献   
797.
回纹型风湿症临床分析   总被引:2,自引:0,他引:2  
目的 回纹型风湿症转归和预后。方法 对15例诊断为回纹型风湿症病人的临床表现及实验室检查进行回顾性分析。结果 病人平均发病年龄为39.2岁,病程为1.5~30年,发作间期为半个月至4个月,80%(12/15)的病人关节发作持续时间为数小时至3d,多次发作期间,检查CRP、血沉、血尿酸、血常规、尿常规结果均示正常。15例回纹型风湿症病人关节受累表现不尽相同,8例病人关节炎作表现为同时多关节受累,其中  相似文献   
798.
799.
Late cerebral radionecrosis may be considered to be a specific chronic inflammatory response, although it is unknown whether the initial damage by brain irradiation is to an endothelial cell or a glial cell. I discuss the pathological specificity of late cerebral radionecrosis by studying the published literature and a case that I experienced. In late cerebral radionecrosis, there are typical coagulation necrosis areas containing fibrinoid necrosis with occlusion of the lumina and poorly active inflammatory areas with many inflammatory ghost cells, focal perivascular lymphocytes, hyalinized vessels, and telangiectatic vascularization near and in the necrotic tissue, and more active inflammatory areas formed as a partial rim of the reactive zone by perivascular lymphocytes, much vascularization, and GFAP-positive astrocytes at the corticomedullary border adjacent to necrotic tissue in the white matter. It is difficult to believe that coagulation necrosis occurs without first disordering the vascular endothelial cells because fibrinoid necrosis is a main feature and a diffusely multiple lesion in late cerebral radionecrosis. Because various histological findings do develop, progress, and extend sporadically at different areas and times in the irradiated field of the brain for a long time after radiation, uncontrolled chronic inflammation containing various cytokine secretions may also play a key role in progression of this radionecrosis. Evaluation of the mechanism of the development/aggravation of late cerebral radionecrosis requires a further study for abnormal cytokine secretions and aberrant inflammatory reactions.  相似文献   
800.

Introduction

Investigation of the conversion rates from normal cognition (NC) to mild cognitive impairment (MCI) is important, as effective early intervention could potentially prevent or substantially delay the onset of dementia. However, reported conversion rates differ across studies and recruitment source. Our study examined predictors of conversion from NC to MCI in a racially and ethnically diverse sample drawn both from community and clinic recruitment sources.

Methods

Rates and predictors of conversion were assessed in an ongoing prospective longitudinal study at University of California, Davis, Alzheimer's Disease Center from 2000 to 2015. Participants (n = 254) were recruited through a clinic (5%) and community sample (95%). They were clinically confirmed as cognitively normal at baseline and followed up to seven years. Recruitment source, demographic factors (age, gender, race/ethnicity, year of education, APOE ε4 positive), cognitive measures (SENAS test scores), functional assessments (CDR sum of boxes), and neuroimaging measures (total brain volume, total hippocampal volume, white hyperintensity volume) were assessed as predictors of conversion from cognitively normal to mild cognitive impairment using proportional hazards models.

Results

Of 254 participants, 62 (11 clinic, 51 community) progressed to MCI. The clinic-based sample showed an annual conversion rate of 30% (95% CI 17%–54%) per person-year, whereas the community-based sample showed a conversion rate of 5% (95% CI 3%–6%) per person-year. Risk factors for conversion include clinic-based recruitment, being older, lower executive function and worse functional assessment at baseline, and smaller total brain volume.

Discussion

Older adults who sought out a clinical evaluation, even when they are found to have normal cognition, have increased risk of subsequent development of MCI. Results are consistent with other studies showing subjective cognitive complaints are a risk for future cognitive impairment, but extend such findings to show that those who seek evaluation for their complaints are at particularly high risk. Moreover, these individuals have subtle, but significant differences in functional and cognitive abilities that, in the presence of concerns and evidence of atrophy on by brain imaging, warrant continued clinical follow-up. These risk factors could also be used as stratification variables for dementia prevention clinical trial design.  相似文献   
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