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991.
目的 为研究与人前列腺癌细胞(PC-3M)侵袭能力相关的靶分子。方法 采用有限稀释法分离单克隆细胞株,并应用单层细胞侵袭等实验鉴定各亚系的体外侵袭能力;借助RT-PCR和免疫组化的方法,分别在转录和翻译水平检测5株侵袭能力不同的PC-3M亚系尿激酶型纤溶酶原激活物受体(u-PAR)的表达。结果 高侵袭亚系u-PAR基因mRNA的表达和蛋白质水平均明显高于低侵袭亚系。结论 PC-3M亚系u-PAR的高表达与其较强的侵袭能力密切相关,而u-PAR可能是抑制高侵袭亚系侵袭效应的一个重要靶分子。  相似文献   
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We measured, by immunohistochemistry, HMGA1 protein expression in 212 breast tissue specimens: 6 normal samples, 28 hyperplastic lesions (13 with cellular atypia), 11 fibroadenomas, 10 in situ ductal carcinomas, 144 ductal carcinomas, and 13 lobular carcinomas. HMGA1 was not expressed in normal breast tissue; HMGA1 staining was intense in 40% of hyperplastic lesions with cellular atypia and in 60% of ductal carcinomas and weak in fibroadenomas and in hyperplastic lesions without cellular atypia. Because HMGA1 expression was similar among ductal breast carcinomas with different histologic grading, we evaluated the association between HMGA1 expression and that of other markers of breast carcinoma invasion (estrogen and progesterone receptors, Ki-67 antigen, and ErbB2) in 21 cases of grade 3 breast ductal carcinomas and 7 cases of breast lobular carcinomas. We found that HMGA1 expression tended to be associated only with c-erbB-2 expression (Spearman rho: 0.36; P=0.065). Taken together, these results suggest that HMGA1 expression might be a novel indicator for the diagnosis and prognosis of human breast cancer.  相似文献   
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Continuous care for the cancer patient is an open concept that is not only applicable only to the terminal stage. Such a simplification could generate inequities of therapy and discrimination. Historically, oncology services have been structured as networks dispensing chemotherapy and radiotherapy rather than services dedicated to the integrated care of the cancer patient. This situation has changed in a continuous and progressive manner over the past few years, as reflected in the latest Spanish Libro Blanco de Oncología. We are still far from reaching the optimum level of integrated care, possibly because we have not, as yet, achieved services that are structured and appropriate for the care-needs of the patient and, perhaps, to the lack of the necessary personnel. We must always make sure that cancer patients receive the best possible treatment, irrespective of whet-her the disease is in relapse. Oncologists must not “give up”, indicating that, in addition to using the most effective anticancer treatments available, they should deploy their best knowledge and experience to control the symptoms of cancer while providing psycho-social help to the patient and family. This is best conducted with a communication that is adjusted to the changing needs of the patient over the longterm clinical process, and should be provided by a multidisciplinary team, according to the needs of the patient and the family. Within a program of integrated care, it is possible to coordinate the existing care structures without creating parallel health networks so as to cover the needs of the greatest number of cancer patients in advanced stage of the disease.  相似文献   
994.
Gastric cancer is the second most frequently diagnosed malignancy worldwide and therefore represents a significant healthcare burden. Environmental and genetic factors are involved in the development of gastric cancer. To date only one clear genetic predisposition has been identified involving mutations in the E-cadherin gene. The disease phenotype in patients harbouring E-cadherin mutations appears to be specifically related to diffuse gastric cancer. Little is known genetically about the other forms of gastric cancer. Since there is a growing awareness about the necessity of early intervention criteria have been developed that aid the identification of hereditary forms of gastric cancer. The aim of the current study was to identify minimal inclusion criteria so that nuclear pedigree families can be provided with risk assessment and/or genetic testing.The results reveal that inclusion features described herein such as (a) gastric cancer diagnosed before 46 years of age; (b) two gastric cancers among first degree relatives diagnosed over the age of 50 are useful in identifying suspected hereditary gastric cancer patients.  相似文献   
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cDNA arrays and proteomic analyses have allowed the rapid identification of specific genes and proteins implicated in multiple tumor types. These molecules must then be validated as clinically relevant prognostic and predictive markers, and this translational research is best conducted in the context of clinical trials. Outcomes data and clinical specimens collected in the ‘Arimidex’, Tamoxifen, Alone or in Combination (ATAC) study, for example, can now be used to compare the expression of biomarkers with clinical outcomes. In this study, adjuvant tamoxifen and anastrozole (‘Arimidex’) were compared alone and in combination in more than 9000 women with breast cancer. Anastrozole was found to be superior to tamoxifen in terms of disease-free survival, time to recurrence, and reduction in the incidence of contralateral tumors. Importantly, tissue specimens from surgical excision, local relapse, and contralateral breast cancer were collected and paraffin-embedded for storage. In the TA01 (TransATAC) program, these specimens will be studied (after obtaining patient consent) using tissue microarrays; tissue biopsy cores 0.6 mm in diameter will be removed from donor blocks and placed on recipient blocks, which will be sectioned to allow the simultaneous analysis of the same samples for multiple biomarkers. These analyses can help determine differential benefits of treatment with anastrozole or tamoxifen, depending on the expression of particular biomarkers in tumor cells. This research also should clarify de novo and acquired resistance mechanisms, and the validation of relevant molecular pathways could guide the development of new drugs. Ultimately, the TA01 program has the potential to favorably impact treatment choices for breast cancer. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
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