Expression of inducible nitric oxide synthase in tumoral and non-tumoral epithelia from bladder cancer patients.

We have previously demonstrated that nitric oxide (NO) is elevated in the urine from bladder cancer patients. As the inducible nitric oxide synthase (iNOS) produces high NO output, the aim of this study was to examine iNOS expression and activity in tumoral (BT) and non-tumoral bladder tissue (NT). iNOS expression was determined by Western blot in 42 BT, 22 NT, and 4 normal bladders (normal B). iNOS activity was evaluated by conversion of [(14)C]l-arginine to [(14)C]l-citrulline plus NO, in additional 15 BT, 8 NT, and 1 normal B. iNOS tissue localization was studied by immunohistochemistry. iNOS expression and activity were found in almost 50% of bladder cancer patients, in both BT and in NT. A similar positive or negative iNOS expression in each pair of NT and BT tissue compared was observed, suggesting that high urine NO levels could be generated by an active iNOS present not only in the tumor but also in the non-tumoral bladder tissue. By immunohistochemistry, heterogeneous iNOS staining was detected in tumor cells from superficial and invasive tumors, while it was not evident in the normal bladder epithelium. A follow-up of 21 patients during 2 years showed recurrences in 80% with positive iNOS. On the contrary, no recurrences were observed in 73% of iNOS negative patients. Our results suggest that iNOS expression in bladder tissue may predispose to cancer recurrences.

High expression of cathepsin B in transitional bladder carcinoma correlates with tumor invasion.

BACKGROUND: Cathepsin B (CB) is a lysosomal cysteine proteinase synthesized as a zymogen of 39-47 kilodaltons (kD), which is subsequently converted into an active single- chain form of 33 kD (CB33) and, by additional processing, into the active 2-chain form containing a heavy chain of 27-29 kD (CB(27-29)) and a light chain of 4-6 kD. Increased or altered CB expression has been documented in a variety of tumor cells, but to the authors' knowledge only one study published to date has reported clinicopathologic significance for CB in transitional cell carcinoma (TCC) of the bladder. METHODS: In this work, CB expression was determined by Western blot analysis in TCC bladder tissue from 30 patients. Nontumor bladder tissue was also analyzed for CB expression. RESULTS: The study results demonstrate higher expression of CB in TCC invasive tumors than in superficial bladder carcinoma. Furthermore, whereas normal bladder only expressed the 29-kD CB protein, tumor and peritumoral tissue demonstrated the 27- to 29-kD CB form. Immunohistochemical staining did not evidence changes in CB localization between tumor and nontumor tissue. CONCLUSIONS: According to the results of the current study, bladder tumor progression appears to be associated with quantitative changes in CB protein expression, as well as with qualitative changes related to the type of CB expressed.

Cirugía de rescate en cáncer de testículo / Ranson surgery in testicular neoplasm

Se presentan datos sobre 16 cirugías de rescate en 15 pacientes portadores de tumor de testículo avanzado. Se evalúan los datos de estadificación, evolución y seguimiento. Se efectúan consideraciones sobre la táctica quirúrgica realizada, los hallazgos operatorios y la histología de las piezas resecadas, valorando además la utilidad de los exámenes complementarios