No impact of blood transfusion on oncological outcome after radical prostatectomy in patients with prostate cancer.

PURPOSE: To assess the association between blood loss, blood transfusion (BT) and biochemical recurrence (BCR)-free, metastasis-free and overall survival after radical prostatectomy (RP) in a large single-center cohort of patients. Perioperative BT at oncologic surgery has been reported to be a potential risk factor for cancer recurrence and survival in several cancer entities. Current studies addressing the relationship between BT, blood loss and BCR-free survival in prostate cancer patients are controversial and include only series with fairly small patient cohorts. MATERIALS AND METHODS: The data of 11,723 patients who underwent RP between 01/1992 and 08/2011 were analyzed. Cox regression analysis, including preoperative PSA level, pT stage, lymph node status, Gleason score, margin status, blood loss, transfusion rate (allogeneic or autologous), tested the relationship between blood loss, transfusion and BCR-free, metastasis-free and overall survival. Additionally, propensity score-matching analysis was performed to adjust differences in tumor characteristics. RESULTS: There was no statistically significant relationship between blood loss or BT and BCR-free, metastasis-free or overall survival. In multivariate analysis PSA level, pT stage, Gleason score, margin status and lymph node status were independent factors for a BCR (p < 0.0001). These results were identical after propensity score matching analysis, comparing patients with and without BT. CONCLUSIONS: This large-scale analysis revealed no correlation between blood loss, blood transfusion and oncological outcome in prostate cancer patients treated with RP. Therefore, the association between higher blood loss or transfusion rate and cancer recurrence as described in other surgical treated tumor entities seems to be irrelevant in prostate cancer patients.

Nitric oxide activates the beta 2 subunit of soluble guanylyl cyclase in the absence of a second subunit.

Previously characterized mammalian soluble guanylyl cyclases form alpha/beta heterodimers that can be activated by the gaseous messenger, nitric oxide, and the novel guanylyl cyclase modulator YC-1. Four mammalian subunits have been cloned named alpha(1), beta(1), alpha(2), and beta(2). The alpha(1)/beta(1) and alpha(2)/beta(1) heterodimeric enzyme isoforms have been rigorously characterized. The role of the beta(2) subunit has remained elusive. Here we isolate a novel variant of this subunit and show that the beta(2) subunit does not need to form heterodimers for catalytic activity because enzyme activity can be measured when it is expressed alone in Sf9 cells. In analogy to the beta(3) subunit recently isolated from the insect Manduca sexta, activity was dependent on the presence of 4 mm free Mn(2+). The EC(50) values for the NO-donor diethylamine/NO were shifted to the left by 1 order of magnitude as compared with the alpha(1)/beta(1) heterodimeric form. In the presence of the detergent Tween, NO sensitivity of beta(2) was abolished, but the enzyme could be activated by protoporphyrin IX, indicating removal of a prosthetic heme group and exchange for the heme precursor. We suggest that the beta(2) subunit is the first mammalian NO-sensitive guanylyl cyclase lacking a heterodimeric structure.

The beta 2 subunit of nitric oxide-sensitive guanylyl cyclase is developmentally regulated in rat kidney.

We have recently shown that nitric oxide activates the beta2 subunit of soluble guanylyl cyclase. In the present study, we show developmental regulation of this subunit. Analysis of mRNA expression by RT-PCR and RNase protection analysis in kidneys revealed no expression of the beta2 subunit in neonatal and strong expression in adult rats. A reciprocal regulation with much lower expression levels was observed in rat lung. Further examination of kidneys from 3, 6, 16, 22, 25, 31 and 36-day-old rats showed that significant expression appears between postnatal day 16 and 22. Isolation of the rat beta2 promoter by genome walking and cloning into a reporter gene vector showed promoter activity for the sense but not the antisense construct providing an in vitro assay for further analysis of the developmental beta2 subunit regulation.