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Aim: We assessed the effect of adding diffusion-weighted magnetic resonance imaging (DW-MRI) to conventional MRI for T staging and the correlation between apparent diffusion coefficient (ADC) values and clinicopathological parameters for patients with bladder cancer. Materials and Methods: We retrospectively reviewed the records of 160 patients with bladder cancer who underwent MRI at our institute. All patients were routinely assessed with conventional MR imaging. Since January 2008, we added DW-MRI. Results: In these 160 patients, 127 (79.4%) tumors were detectable by MRI. In all patients with detectable tumors, on a stage-by-stage basis, 96 (75.6%) of 127 patients received the correct diagnosis. With DW-MRI, accurate diagnosis was obtained in 80 (80.0%) of 100 cases; without DWI in only 16 (59.3%) of 27 cases (P = 0.026). For T staging, the accuracy for distinguishing muscle invasion (T ≦ 1 vs T ≧ 2) with DW-MRI (83.0%) was superior to that without DW-MRI (66.7%). The accuracy for distinguishing perivesical fat invasion (T ≦2 vsT ≧3) with DW-MRI (98.0%) was also superior to that without DW-MRI (92.6%). The ADC values were significantly related with tumor diameter (<3 cm vs ≧ 3 cm,P < 0.001), histopathological grade (low grade vs high grade, P < 0.001), T stage (≦T1 vs≧T2,P < 0.001), and operative method (transurethral resection vs total cystectomy, P < 0.001). Conclusions: We demonstrated that DW-MRI is not only useful for bladder cancer T staging, but also a prognostic factor for patients with bladder cancer. [ABSTRACT FROM AUTHOR]

Background: There is currently no consensus on the correlations between androgen concentrations in prostate tissue and blood and stage and pathological grade of prostate cancer. In this study, we used a newly-developed ultra-sensitive liquid-chromatography tandem mass spectrometry method to measure testosterone (T) and dihydrotestosterone (DHT) concentrations in blood and needle biopsy prostate specimens from patients with prostate cancer. Methods: We analyzed androgen levels in 196 men diagnosed with prostate cancer. All patients had undergone systematic needle biopsy, and an additional needle biopsy from the peripheral zone was conducted for the simultaneous determination of T and DHT. We analyzed the relationships between T and DHT levels in tissue and blood and Gleason score, clinical stage, and percentage of positive biopsy cores, using multivariate analysis. Results: The median T and DHT levels in blood were 3551.0 pg/mL and 330.5 pg/mL, respectively. There was a strong correlation between serum T and DHT. The median T and DHT levels in prostate tissue were 0.5667 pg/mg and 7.0625 pg/mg, respectively. In multivariate analysis, serum prostate-specific antigen and tissue T levels were significantly associated with poor prognosis; high T levels in prostate tissue were significantly related to high Gleason score (p = 0.041), advanced clinical stage (p = 0.002), and a high percentage of positive biopsy cores (p = 0.001). Conclusions: The results of this study indicate that high T levels in prostate tissue are related to high Gleason score, advanced clinical stage, and a high percentage of positive biopsy cores in patients with prostate cancer. T level in needle biopsy specimens may therefore be a useful prognostic factor in prostate cancer patients. [ABSTRACT FROM AUTHOR]

Activation of tumor-stromal interactions is considered to play a critical role in the promotion of tumorigenesis. To discover new therapeutic targets for hormone-refractory prostate tumor growth under androgen ablation therapy, androgen-sensitive LNCaP cells and the derived sublines, E9 (androgen-low-sensitive), and AIDL (androgen-insensitive), were recombined with androgen-dependent embryonic rat urogenital sinus mesenchyme (UGM). Tumors of E9 + UGM and AIDL + UGM were approximately three times as large as those of LNCaP + UGM. Tumors grown in castrated hosts exhibited reduced growth as compared with those in intact hosts. However, in castrated hosts, E9 + UGM and AIDL + UGM tumors were still approximately twice as large as those of LNCaP + UGM. Cell proliferation in tumors of E9 + UGM and AIDL + UGM grown in castrated host, was significantly higher than that in tumors of LNCaP + UGM. In vitro, expression of fibroblast growth factor (FGF)-2 and IGF-I, but not FGF-7 mRNA, was significantly reduced in UGM under androgen starvation. In cell culture, E9 cells were responsive to FGF-2 and FGF-7 stimulation, while AIDL responded to FGF-7 and IGF-1. Expression of FGFR1 and FGFR2 was considerably higher in E9 than those in LNCaP, similarly expression of FGFR2 and IGF-IR were elevated in AIDL. These data suggest that activation of prostate cancer cell growth through growth factor receptor expression may result in the activity of otherwise androgen-independent stromal growth factor signals such as FGF-7 under conditions of androgen ablation. [ABSTRACT FROM AUTHOR]

Zinc content in rat lateral prostate (LP) is higher compared with theother tissues, but the zinc retention system in the prostate remains unclear.In the present study, we examined the expression of ZRT, a IRT-like protein(ZIP) family transporter in rat prostate. The zinc level in rat LP was highercompared with the ventral (VP) and dorsal prostate (DP). The predictedZIP2 mRNA was really expressed in LP at a high level. The expression wasdecreased in LP from castrated rats, associated with a decrease in zinclevel, and these changes were prevented by testosterone replacement.Moreover, ZIP2 expression levels in LP positively correlated with the zinclevels. These findings strongly suggest that ZIP2 is involved in zinc homeostasisof rat prostate. [ABSTRACT FROM AUTHOR]

The methylation status of 7 genes was examined in four cell lines, 36 samples of benign prostatic hyperplasia (BPH), 20 samples of prostatic intraepithelial neoplasia (PIN) and 109 samples of prostate cancer (PCa), using methylation-specific PCR (MSP): the pi-class glutathione S-transferase (GSTP1), retinoic acid receptor beta 2(RARβ2), androgen receptor (AR), death-associated protein kinase (DAPK), tissue inhibitor of metalloproteinase-3 (TIMP-3), O6-methylguanine DNA methyltransferase (MGMT), and hypermethylated in cancer-1 (HIC-1). The frequencies of methylation in PCa were 88% for GSTP1, 78% for RARβ2, 36% for DAPK, 15% for AR, 6% for TIMP-3, and 2% for MGMT, whereas the values were 11% for AR and DAPK, 6% for TIMP-3, 3% for GSTP1, and 0 for RARβ2 and MGMT in BPH. Aberrant methylation of the GSTP1 and RARβ2 genes was detected in 30% and 20% of PIN, respectively. Most samples of BPH and PCa were positive for HIC-1 methylation. Regarding accumulation of methylated cancer-related genes, there were significant correlations between PCa and BPH as well as PIN and BPH. In the present study, a high frequency of aberrant promoter methylation of the GSTP1 and RARβ2 genes was noted in PCa. Our findings suggest that methylation of cancer-related genes may be involved in carcinogenesis of the prostate. © 2003 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]