Do neuroendocrine cells in human prostate cancer express androgen receptor?

The presence of androgen receptors (AR) in neuroendocrine cells was investigated in benign tissue of 10 prostatectomy specimens, in 12 prostatic adenocarcinomas with focal neuroendocrine differentiation and in 1 case of a pure neuroendocrine small cell carcinoma of the prostate. Neuroendocrine cells were defined by their reactivity with an antibody to chromogranin A. Monoclonal antibody F39.4 directed against the amino-terminal domain of the AR molecule was used to detect AR. AR and chromogranin A were simultaneously visualized with a double immunofluorescence technique. The results indicate that chromogranin positive cells in both benign and malignant prostatic tissue lack detectable expression of AR. No effect of endocrine therapy was noted. These results are in agreement with the hypothesis that prostatic neuroendocrine tumour cells represent an androgen insensitive cell population, which incidentally may expand to replace the androgen-sensitive tumour cell population during androgen ablation therapy

Prognostic factors in renal-cell carcinoma: Immunohistochemical detection of p53 protein versus clinico-pathological parameters

Immunoreactivity forp53 protein was assessed in 100 cases of primary renal-cell carcinoma (RCC). The results were correlated with clinical survival data (follow-up 24 to 84 months: mean: 39 months) and with clinico-pathological parameters, including nuclear grade, tumour stage, cell type, tumour architecture and tumour diameter. In all, 32% of the tumours were p53-positive; there was no difference in survival between p53-positive and -negative cases. Similarly, p53 expression did not correlate with any of the clinico-pathological parameters mentioned. Nuclear grade (grade 1 + 2 vs. grade 3 + 4) had a striking impact on prognosis and so, to a lesser extent, did tumour stage and the occurrence of a spindle-cell component. The immunohistochemical detection of p53 in RCC is not of prognostic value. The estimation of nuclear grade, however is a major predictor of prognosis

Nitrogen source apportionment for the catchment, estuary and adjacent coastal waters of the Scheldt.

Using the systems approach framework (SAF), a coupled model suite was developed for simulating land-use decision making in response to nutrient abatement costs and water and nutrient fluxes in the hydrological network of the Scheldt River, and nutrient fluxes in the estuary and adjacent coastal sea. The purpose was to assess the efficiency of different long-term water quality improvement measures in current and future climate and societal settings, targeting nitrogen (N) load reduction. The spatial-dynamic model suite consists of two dynamically linked modules: PCRaster is used for the drainage network and is combined with ExtendSim modules for farming decision making and estuarine N dispersal. Model predictions of annual mean flow and total N concentrations compared well with data available for river and estuary (r² ≥ 0.83). Source apportionment was carried out to societal sectors and administrative regions; both households and agriculture are the major sources of N, with the regions of Flanders and Wallonia contributing most. Load reductions by different measures implemented in the model were comparable (~75% remaining after 30 yr), but costs differed greatly. Increasing domestic sewage connectivity was more effective, at comparatively low cost (47% remaining). The two climate scenarios did not lead to major differences in load compared with the business-as-usual scenario (~88% remaining). Thus, this spatially explicit model of water flow and N fluxes in the Scheldt catchment can be used to compare different long-term policy options for N load reduction to river, estuary, and receiving sea in terms of their effectiveness, cost, and optimal location of implementation

Variation of prostate-specific antigen expression in different tumour growth patterns present in prostatectomy specimens

A series of 55 randomly chosen radical prostatectomy specimens was analyzed for expression of prostate-specific antigen (PSA) by immunohistochemical techniques. Tissue sections were selected in such a manner that in addition to glandular benign prostatic hyperplasia (BPH), one or more different prostatic tumour growth patterns were present. Four monoclonal antibodies, directed against three different PSA epitopes, and one polyclonal anti-PSA antiserum were used. Expression of PSA was compared with that of prostate-specific acid phosphatase (PAP), recognized by two different polyclonal antisera. A critical dilution aimed at a maximum of staining intensity on BPH tissue sections was chosen for all antibodies. Anti-PSA and anti-PAP antisera stained essentially all BPH samples (over 90%). Irrespective of the nature of the antibodies used, PSA expression was found to be decreased in prostatic carcinoma. A clear cut relationship was found between immunoreactivity for PSA and the degree of differentiation of the tumour area. Under the experimental conditions used the PSA monoclonal antibodies stained only 1 out of 10 undifferentiated carcinomas, whereas 50% to 70% of the well- and moderately-differentiated carcinomas showed immunoreactivity. This correlation was less pronounced with the PAP staining pattern. If the PSA antibody titer was raised the percentage of clearly staining undifferentiated carcinomas could be considerably increased (up to 60%-100%), indicating that PSA expression is not absent, but lowered in most (if not all) undifferentiated carcinomas