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Recent studies demonstrate the relationship of microvessel density to malignant progression in breast cancer (N. Weidner, J. P. Semple, W. R. Welch, and J. Folkman, N. Engl. J. Med., 324: 1-8, 1991), underscoring the importance of angiogenesis in this tumor. Crucial in tumor angiogenesis are the paracrine actions of tumor-secreted factors (e.g., vascular endothelial growth factor), which have been thought to derive from the tumor epithelial cells themselves. We demonstrate that in response to hypoxic conditions, human mammary fibroblasts dramatically up-regulate vascular endothelial growth factor mRNA and increase vascular endothelial growth factor protein levels in accordance with the degree of oxygen deprivation. Thus, mammary stromal cells, only recently considered in the regulation of breast carcinomas, may play a hitherto unrealized role in breast cancer angiogenesis. 相似文献
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CE Iselin CN Robertson GD Webster J Vieweg DF Paulson 《Canadian Metallurgical Quarterly》1997,158(6):2123-2126
PURPOSE: We determined if urethral preservation and orthotopic bladder replacement in patients with transitional cell carcinoma within the prostatic urethra or prostate placed these patients at risk for urethral recurrence or death. MATERIALS AND METHODS: The clinical course of all patients undergoing urethral preservation and orthotopic bladder replacement was reviewed. The urethra was sacrificed only if the distal prostatic urethral margin was positive for transitional cell carcinoma. The pathological T stage and the grade of the primary malignancy, local recurrence, site of recurrence (urethral, pelvic, distant) and death were documented. RESULTS: Of 81 patients 70 were evaluable (June 1996) with a mean followup of 35 months. Of the 70 patients 48 were alive without evidence of disease for a mean of 38 months (range 8 to 107) and 5 died without evidence of disease. Eight of these 53 patients (15%) had prostatic involvement (carcinoma in situ in 6, intraductal carcinoma in 1 and stromal invasive transitional cell carcinoma in 1). Of the 70 patients 17 had disease recurrence (13 died of disease and 4 are alive, 1 of whom had urethral recurrence without initial prostatic transitional cell carcinoma). Of the 17 patients (35%) 6 had transitional cell carcinoma prostatic involvement (carcinoma in situ in 4 and stromal invasion in 2), and 5 of these 6 died, none with or of urethral recurrence but of the primary bladder pathology. Of these 5 patients 1 had stromal invasive transitional cell carcinoma of the prostate and experienced a bulbar urethra recurrence at 1 month and a pelvic recurrence at 3 months, and died at 5 months. Death was not secondary to the urethral recurrence. Thus, of the 14 patients who had prostatic transitional cell carcinoma, only 1 had urethral recurrence (7%), and this recurrence did not present as the cause of death. CONCLUSIONS: The guidelines for urethral resection can be relaxed, increasing the opportunities for orthotopic reconstruction, without placing the patients at increased risk for death of transitional cell carcinoma. 相似文献