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991.
Bowers DC Mulne AF Reisch JS Elterman RD Munoz L Booth T Shapiro K Doxey DL 《Cancer》2002,94(4):1094-1101
BACKGROUND: Nonperioperative strokes are rare yet potentially devastating events for children with central nervous system (CNS) tumors. The incidence of and risk factors for nonperioperative strokes in children with CNS tumors is unknown. METHODS: The authors performed a retrospective review of children from their institution with CNS tumors. The incidence of stroke in the nonperioperative period and the influence of patient demographic factors, coexisting genetic diseases, tumor type, and treatment modality on the subsequent occurrence of a stroke were determined. RESULTS: Eight hundred seven consecutive patients from the authors' institution with CNS tumors were observed for a combined 3224 nonperioperative years. Thirteen patients (1.6%) had a nonperioperative stroke, for an incidence of 4.03 strokes/1000 years of nonperioperative patient follow-up. Eight patients were males, and the median age at diagnosis of a CNS tumor was 4.8 years (range, 0.3-18.6 years). The median duration from diagnosis of a CNS tumor until the occurrence of stroke was 2.3 years (range, 0.3-15.8 years). Among numerous potential risk factors individually examined by chi-square analysis, only treatment with radiation therapy was associated with the subsequent development of a stroke (chi-square, P = 0.007). By logistic regression analysis, treatment with radiation therapy and a diagnosis of an optic pathway glioma were the only statistically significant variables associated with a stroke. CONCLUSIONS: Strokes are much more common among children with CNS tumors. Children treated with radiation therapy and those with optic pathway gliomas have a higher association with the occurrence of a subsequent nonperioperative stroke. Because children with optic pathway gliomas may be at particularly high risk of stroke after radiation therapy, the desired beneficial therapeutic effects of irradiation must always be weighed against its potentially adverse effects, including stroke. 相似文献
992.
Monoclonal antibodies to target epidermal growth factor receptor-positive tumors: a new paradigm for cancer therapy 总被引:12,自引:0,他引:12
BACKGROUND: Traditional cytotoxic approaches to tumor management are associated with efficacy and toxicity limitations. Blockade of the epidermal growth factor receptor (EGFR) and its ligands is a novel approach to the treatment of human tumors that offers a noncytotoxic alternative to cancer treatment. METHODS: An English-language literature search was conducted to identify studies assessing the in vitro and in vivo effects of EGFR blockade with an emphasis on approaches that use monoclonal antibody therapy. RESULTS: The EGF pathway regulates normal cellular processes and appears to be correlated with the development of malignancy. Approximately 30% of human tumors express EGFR, which has been reported to be correlated with poor prognosis and diminished disease-free and overall survival in selected tumor types. A number of anti-EGFR monoclonal antibodies have been developed, which currently are undergoing clinical trials in humans. Effective anti-EGFR monoclonal antibodies compete with endogenous ligands, primarily EGF and transforming growth factor-alpha, for receptor ligand-binding sites. Binding to EGFR blocks critical signaling pathways and interferes with the growth of tumors expressing EGFR. Anti-EGFR monoclonal antibodies that currently are under study include IMC-C225, EMD 55900, ICR 62, and ABX-EGF. CONCLUSIONS: These antibodies have demonstrated promising results and appear to have been well tolerated. EGFR-targeted therapy addresses important, unmet needs in the treatment of human tumors, particularly EGFR-positive epithelial tumors including common malignancies of the head and neck, lung, and colon. 相似文献
993.
Gutman M Couillard S Roy J Labrie F Candas B Labrie C 《International journal of cancer. Journal international du cancer》2002,99(2):273-278
EM-652 exerts pure antiestrogenic activity in the mammary gland and endometrium, while tamoxifen, the antiestrogen most widely used for the treatment of breast cancer, exerts mixed antiestrogenic-estrogenic activity in these tissues. Our objective was to compare the agonistic and antagonistic effects of EM-652 with tamoxifen and 5 other antiestrogens on the growth of ZR-75-1 human breast xenografts in ovariectomized nude mice. During the 23 weeks of treatment at a daily oral dose of 50 microg, EM-652 was the only compound that decreased tumor size relative to pretreatment values, whereas the 6 other antiestrogens only decreased to various extents the progression rate stimulated by estrone. Under estrone stimulation, all groups of animals had more than 60% of their tumors in the progression category except for the EM-652-treated group, where only 7% of the tumors progressed. In the absence of estrone stimulation, progression was seen in 60%, 33%, 21% and 12% of tumors in the tamoxifen-, idoxifene-, toremifene- and raloxifene-treated groups, respectively, while only 4% of tumors progressed in the EM-652-treated group. The agonistic and antagonistic actions of each antiestrogen were also measured on endometrial epithelial cell thickness. Our present findings indicate that EM-652, in addition to being the most potent antiestrogen on human breast tumor growth, has no agonistic effect in breast and endometrial tissues. Since previous data have shown benefits of EM-652 on bone density and lipid profile, this compound could be an ideal candidate for chemoprevention of breast and uterine cancers, while protecting against osteoporosis and cardiovascular disease. 相似文献
994.
Basu P Sankaranarayanan R Mandal R Roy C Das P Choudhury D Datta K Karamakar S Tsu V Chakrabarti RN Siddiqi M;Calcutta Cervical Neoplasia Early Detection Strudy 《International journal of cancer. Journal international du cancer》2002,100(1):92-96
Unaided visual inspection or "downstaging" has been suggested as a potential alternative method for cervical cancer screening in developing countries. Our study was designed to evaluate the accuracy of downstaging to detect cervical neoplasia in a low-resource setting. A total of 6,399 women aged 30-64 years were screened with downstaging by trained nonmedical health workers. Two thresholds were used to define positive downstaging: "low threshold" when any visible abnormality on the cervix was considered positive and "high threshold" when selected abnormalities such as bleeding on touch, bleeding erosion, hypertrophied oedematous cervix, congested stippled cervix and growth or ulcer constituted the positive test. All women underwent a colposcopy examination. Biopsies were directed when colposcopy revealed abnormal lesions. True disease status was defined as histologically proven moderate dysplasia and worse lesions. Since all the participants received a diagnostic (reference) investigation (biopsy and/or colposcopy), sensitivity, specificity and predictive values were estimated directly. Low- and high-threshold downstaging were positive in 1,585 (24.8%) and 460 (7.2%) women, respectively. The sensitivities of low- and high-threshold downstaging to detect high-grade precursors and invasive cancers were 48.9% and 31.9%, respectively. The specificities were 75.8% and 93.3%, respectively. These results indicate that downstaging is not suitable as an independent primary screening modality for cervical neoplasia. 相似文献
995.
The E-cadherin cell-cell adhesion complex and lung cancer invasion, metastasis, and prognosis 总被引:26,自引:0,他引:26
BACKGROUND: Lung cancer is the most common cause of cancer deaths in the western world. Progress in treatment results has been limited, and the prognosis is poor with a 5-year survival less than 15%. Based on new developments in molecular biology, our knowledge about lung carcinogenesis and mechanisms for invasion and metastasis has expanded and may in the future lead to more specific targeted therapies and better prognosis. The E-cadherin-catenin complex is critical for intercellular adhesiveness and maintenance of normal and malignant tissue architecture. Reduced expression of this complex in malignant disease is associated with tumour invasion, metastasis, and unfavorable prognosis. METHODS: This review is based on search in the Medline database from 1991 to 2001. We have reviewed the relevance of the E-cadherin-catenin adhesion complex in malignancy in general and lung cancer in particular. Furthermore, its role as target for specific therapy is discussed. RESULTS: Available data indicate that alterations of proteins involved in the E-cadherin-catenin complex are early incidents in cancer development. Reduced or altered expression of one or more of the components in this complex is associated with extended invasive and progressive behavior of cancer cells. Consistently, the E-cadherin-catenin complex appears to be increasingly delicate with regard to cancer prognosis. beta-Catenin, one of the components of the adhesion complex, also plays a significant role in cell signal transduction, gene activation, apoptosis inhibition, and increased cellular proliferation and migration. CONCLUSION: Inactivation of the E-cadherin-catenin adhesion complex, induced by genetic and epigenetic events, plays a significant role in multistage carcinogenesis, and seems to be associated with dedifferentiation, local invasion, regional metastasis, and reduced survival in lung cancer. 相似文献
996.
Induction of apoptosis in human cancer cell lines by diospyrin,a plant-derived bisnaphthoquinonoid,and its synthetic derivatives 总被引:2,自引:0,他引:2
Diospyrin, a bisnaphthoquinonoid natural product, and three synthetic derivatives have been tested for their action in four human cancer cell lines: acute myeloblastic leukemia (HL-60), chronic myelogenic leukemia (K-562), breast adenocarcinoma (MCF-7) and cervical epithelial carcinoma (HeLa). In cells grown in appropriate media several derivatives elicited cytotoxicity as assessed by Trypan Blue dye exclusion, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide reduction and DNA synthesis. Diethyl ether derivative (D7) was most effective in this regard while the parent compound diospyrin (D1) was least active (D7>D3>D2>D1). D7 was not cytotoxic toward normal human lymphocytes, suggesting its action is specific for tumor cells. On microscopic examination D7-treated cells exhibited characteristic morphological features of apoptosis, such as cell shrinkage and formation of apoptotic bodies. Fluorescent staining with propidium iodide revealed distinct chromatin condensation and nuclear fragmentation. The apoptotic index paralleled cytotoxic parameters, and fragmented DNA extracted free of genomic DNA displayed on gel electrophoresis a typical ladder pattern. D7-induced apoptosis was mediated via activation of caspase 3 and caspase 8. 相似文献
997.
Smad4 induces the tumor suppressor E-cadherin and P-cadherin in colon carcinoma cells 总被引:14,自引:0,他引:14
Müller N Reinacher-Schick A Baldus S van Hengel J Berx G Baar A van Roy F Schmiegel W Schwarte-Waldhoff I 《Oncogene》2002,21(39):6049-6058
998.
Regine WF Huhn JL Patchell RA St Clair WH Strottmann J Meigooni A Sanders M Young AB 《International journal of radiation oncology, biology, physics》2002,52(2):333-338
PURPOSE: A single-institution experience using primary stereotactic radiosurgery (SRS) alone in the management of newly diagnosed brain metastases was analyzed to identify the risk of symptomatic brain tumor recurrence (BTR) and neurologic deficit associated with such a treatment strategy. METHODS AND MATERIALS: Thirty-six patients were treated for newly diagnosed single/multiple brain metastases using SRS alone followed by planned observation. SRS minimum tumor dose ranged from 8 to 25 Gy (median: 20 Gy). Factors evaluated in analysis of treatment outcome included number of metastases, site of metastasis, primary tumor site, histology, extent of intracranial and extracranial disease, and interval to diagnosis of brain metastasis. RESULTS: Median and 1-year survival for the entire group was 9 months and 36%, respectively. BTR anywhere in the brain occurred in 47% (17/36) of patients. Forty-seven percent of BTR (8/17) recurred at the site of original metastasis; 35% (6/17) recurred at both original [corrected] and distant sites in the brain, and 18% (3/17) recurred at distant only [corrected] brain sites. Seventy-one percent (12/17) of the patients were symptomatic at the time of recurrence, and 59% (10/17) had an associated neurologic deficit. Multivariate analysis found that only the extent of disease was a predictor of BTR. Patients who had disease limited to the brain only had a BTR rate of 80% (8/10) vs. 35% (9/26) who had disease involving the brain, primary site, and/or other extracranial metastatic sites (p = 0.03). CONCLUSIONS: Use of primary SRS alone in this setting is associated with an increasingly significant risk of BTR with increasing survival time. In addition, the majority of such recurrences are symptomatic and associated with a neurologic deficit, a finding not analyzed in recently reported experiences withholding whole brain radiation therapy as part of the primary treatment of brain metastasis. 相似文献
999.
La Russa VF Schwarzenberger P Miller A Agrawal K Kolls J Weiner R 《Cancer investigation》2002,20(1):110-123
1000.
Roy A 《Journal of psychiatric research》2002,36(3):173-177
OBJECTIVE: To examine whether childhood trauma may have a relationship to hypothalamic-pituitary-adrenal (HPA) axis function as an adult. METHODS: Forty-six withdrawn cocaine dependent patients participated in 24-h urine collections for determination of urinary-free cortisol (UFC) and completed the Childhood Trauma Questionnaire (CTQ). RESULTS: Patients with a mean UFC output below the median had significantly higher CTQ scores for childhood sexual abuse than patients with UFC outputs above the median. Multiple regression analysis showed that both childhood emotional neglect and sexual abuse were independently associated with UFC outputs. CONCLUSION: These cross sectional data, in a sample of middle-aged cocaine dependent patients, suggest the possibility that childhood trauma may have an effect on HPA axis function and thus predispose to psychiatric disorders. Further studies are needed in different samples. 相似文献