No abstract

The death receptor Fas (Apo1/CD95) and Fas ligand (FasL) system is recognised as a major pathway for the induction of apoptosis in vivo, and antiapoptosis via its blockade plays a critical role in carcinogenesis and progression in several malignancies. However, the function of Fas -FasL system in urothelial cancer (UC) has not been elucidated. We therefore investigated the expression of Fas, FasL and Decoy receptor 3 for FasL (DcR3) in UC specimens and cell lines, and examined the cytotoxic effect of an anti-Fas-activating monoclonal antibody (mAb) in vitro. Immunohistochemical examinations of Fas-related molecules were performed on 123 UC and 30 normal urothelium surgical specimens. Normal urothelium showed Fas staining in the cell membrane and cytoplasm. In UC, less frequent Fas expression was significantly associated with a higher pathological grade (Po0.0001), a more advanced stage (P ¼ 0.023) and poorer prognosis (P ¼ 0.010). Fas and the absence thereof were suggested to be crucial factors with which to select patients requiring more aggressive treatment. Moreover, low-dose anti-Fas-activating mAb sensitised resistant cells to adriamycin, and this synergistic effect could be applied in the development of new treatment strategy for UC patients with multidrug-resistant tumours.

No abstract

Immunotherapy is the only available treatment for metastatic renal cell cancer (RCC), but the response rate is only about 20% and the treatment is occasionally associated with severe adverse effects. Thus, the selection of patients with a high susceptibility to immunotherapy is needed; however, there is no promising molecular marker that can predict the response to immunotherapy for RCC. This study was carried out to elucidate the potential role of apoptosis-related molecules Bcl-2 and Fas, as well as apoptotic and proliferating indexes (AI, PI) as predictors of the susceptibility of metastatic RCC to immunotherapy. Immunohistochemical examination of tumour tissues from 40 patients with metastatic RCC undergoing postoperative immunotherapy after radical nephrectomy was performed. Patients with progressive disease (PD) after immunotherapy presented with decreased survival (P ¼ 0.006). Progressive disease correlated with higher PI in the primary lesion (P ¼ 0.0087). All primary tumours of CR or PR patients were negative for Bcl-2, whereas among NC þ PD patients, 40.6% were positive for Bcl-2 (P ¼ 0.0373). Patients in whom the primary tumours were both Bcl-2-and Fas-negative showed significantly better responses to immunotherapy in comparison with the remaining group (P ¼ 0.0022). The Bcl-2 and Fas status of the primary lesion may become useful criteria for the selection of patients with metastatic RCC for immunotherapy.

Mixed epithelial and stromal tumor of the kidney (MESTK) is a rare kidney neoplasm that almost exclusively occurs in perimenopausal women, and long-term estrogen replacement is relevant to its pathogenesis. Herein is described an atypical case of MESTK uncovered in a 12-year-old premenarcheal girl without a history of prior estrogen use. On surgical specimen it was found that the well-circumscribed tumor measuring 14 cm arose from the lower pole of the right kidney, showing solid and fibrous-cystic areas. Microscopically, it was composed both of epithelial structures similar to renal tubules and stroma comprising non-specific spindle cells. Some intratumoral tubules showed affinities to distal-nephron-specific lectins, and those immunoreactive for proximal-tubule-specific CD15 were also present. In addition, primitive ductal structures were reactive both for CD15 and lectins, but immature epithelial elements typical of nephroblastoma were absent. Spindle cells were positive for actin, desmin and vimentin, and expressed progesterone and estrogen receptors. The tumor was comparable with MESTK, although some epithelia were associated with the immunophenotype of proximal tubules. The patient was free of disease postoperatively for 40 months. In the present case, remnants of the primitive periductal mesenchyme might be promoted to neoplastic cells by a sex-steroid surge during puberty.