Epigenetic silencing of the dual-role signal mediator, ANGPTL4 in tumor tissues and its overexpression in the urothelial carcinoma microenvironment.

Urothelial carcinoma (UC) carcinogenesis has been hypothesized to occur through epigenetic repression of tumor-suppressor genes (TSGs). By quantitative real-time polymerase chain reaction array, we found that one potential TSG, angiopoietin-like 4 (ANGPTL4), was expressed at very low levels in all bladder cancer cell lines we examined. Previous studies had demonstrated that ANGPTL4 is highly expressed in some cancers, but downregulated, by DNA methylation, in others. Consequently, owing to these seemingly conflicting functions in distinct cancers, the precise role of ANGPTL4 in the etiology of UC remains unclear. In this study, using methylation-specific PCR and bisulfite pyrosequencing, we show that ANGPTL4 is transcriptionally repressed by DNA methylation in UC cell lines and primary tumor samples, as compared with adjacent noncancerous bladder epithelium. Functional studies further demonstrated that ectopic expression of ANGPTL4 potently suppressed UC cell proliferation, monolayer colony formation in vitro, and invasion, migration, and xenograft formation in vivo. Surprisingly, circulating ANGPTL4 was significantly higher in plasma samples from UC patients than normal control, suggesting it might be secreted from other cell types. Interestingly, our data also indicated that exogenous cANGPTL4 could promote cell proliferation and cell migration via activation of signaling through the Erk/focal adhesion kinase axis. We further confirmed that mouse xenograft tumor growth could be promoted by administration of exogenous cANGPTL4. Finally, immunohistochemistry demonstrated that ANGPTL4 was downregulated in tumor cells but overexpressed in tumor adjacent stromal tissues of muscle-invasive UC tissue samples. In conclusion, our data support dual roles for ANGPTL4 in UC progression, either as a tumor suppressor or oncogene, in response to microenvironmental context.

Transurethral microwave thermotherapy for symptomatic benign prostatic hyperplasia: long-term durability with Prostcare.

OBJECTIVE: To evaluate the long-term durability of transurethral microwave thermotherapy (TUMT) with Prostcare for symptomatic benign prostatic hyperplasia (BPH). PATIENTS AND METHODS: From August 1993 to July 1994, a total of 65 patients with symptomatic BPH who underwent TUMT using the Prostcare apparatus (Bruker Spectospin, Wissembourg, France) with low-energy protocol (maximal power 52 W) were enrolled into a short-term evaluation. Subsequent follow-up information was collected in July 1999. If patients had had any further therapy for BPH, the date of retreatment was considered as an endpoint of TUMT efficacy. If no further therapy for BPH had been needed, they were re-assessed for overall satisfaction. RESULTS: The median follow-up period was 49 months. Twenty patients were excluded for various reasons, including 17 with loss of follow-up and 3 with new diseases that could affect the voiding status. Thirty-eight (84.4%) of 45 valuable patients had received further therapy for BPH, including medication (n = 21, 46.7%), and endoscopic surgery (n = 17, 37.7%). The times to pharmacologic or endoscopic retreatment after TUMT were 8.9+/-11.1 and 23.0+/-14.4 months, respectively (p = 0.0003, log rank test). Only 7 (15.5%) patients had no further treatment, with 3 having satisfactory improvements, but 4 feel dissatisfied yet not needing any further therapy. In addition, 2 patients complained of erectile dysfunction after TUMT and 1 was diagnosed with prostate cancer 50 months after TUMT. In addition, there was no significant difference for all baseline values among three groups with no retreatment or retreatment with medication or endoscopic surgery. CONCLUSION: At the 5-year follow-up, the long-term durability of low-energy TUMT with Prostcare is only exhibited in a few patients and the overall retreatment rate was 84.4%. Thus, patient should be informed of the high probability of supplementary treatment after TUMT.

Transurethral microwave thermotherapy for symptomatic benign prostatic hyperplasia: short-term experience with Prostcare.

PURPOSE: To assess our short-term experience with transurethral microwave thermotherapy (TUMT) for symptomatic benign prostatic hyperplasia (BPH). PATIENTS AND METHODS: From August 1993 through July 1994, in total 65 patients with symptomatic BPH were enrolled into this study. The patients' ages ranged from 56 to 95 years with a mean of 70 years. Under local anesthesia with intraurethral instillation of Xylocaine jelly only, all patients received one session of TUMT for up to 60 min with Prostcare equipment. Uroflowmetry was performed and international prostatic symptom score (IPSS) determined before 3 and 6 months after TUMT for assessment of efficacy. All adverse events were recorded and evaluated for clinical relevance. RESULTS: At 3 and 6 months following TUMT, the mean IPSS decreased from 19.7 +/- 6.8 (baseline) to 12.8 +/- 8.2 (-46%) and to 15.5 +/- 9.0 (-21%), respectively; the maximal urine flow rate at 3 and 6 months increased from 9.1 +/- 4.8 ml/s (baseline) to 11.0 +/- 4.9 ml/s (+21%) and to 10.9 +/- 5.6 ml/s (+19%), respectively. During TUMT, burning sensation was the most frequent complaint (38.5%), followed by urethral discomfort (29.2%) and urgency (9.2%). Two patients (3.1%) interrupted TUMT, because of intolerable pain. Following TUMT micturition pain (73.8%) and gross hematuria (45.9%) were the most adverse events. Most of these adverse events disappeared within 2 weeks. One patient suffered from skin erosion over the penoscrotal junction 1 week later. None had retrograde ejaculation; 1 patient complained of erectile dysfunction. CONCLUSION: Although the efficacy of TUMT with Prostcare became less prominent 6 months after TUMT, TUMT was still a tolerable, safe alternative treatment of BPH, especially in patients who were not suitable for transurethral resection of the prostate or anesthesia.

Role of cyclic adenosine monophosphate in prostaglandin E1-induced penile erection in rabbits.

To investigate the role of cyclic adenosine monophosphate (cAMP) in penile erection in relation to the effect of prostaglandin E1 (PGE1) male adult New Zealand white rabbits were utilized as a model to study intracavernous pressure (ICP) in vivo. After intracavernous injection of PGE1 (0.2-1.6 micrograms/kg) and 8-bromocyclic adenosine monophosphate (8-Br-cAMP, 0.5-1.5 mg/kg), both drugs raised the ICP in a dose-dependent manner. The increased ICPs induced by PGE1 and 8-Br-cAMP were 33.4 +/- 8.12 and 24.1 +/- 4.9 mm Hg, respectively (p < 0.05, paired Student's t test). Administrations of cyclic adenosine monophosphothioate, Rp-isomer (cAMP antagonist, 0.02-0.08 mumol/kg) prior to PGE1 injections inhibited the effect of PGE1 in vivo in a dose-dependent manner. The systemic blood pressures and heart rates in rabbits were unchanged during all the intracavernous injections. The corpus cavernosal tissues isolated from rabbits were studied for the cAMP contents after incubation of different doses of PGE1 in vitro. The cAMP contents were also elevated in a manner parallel with the increases in PGE1 concentrations (3-9 microM). We conclude: (1) the feasibility of intracavernous injection of vasoactive drugs is similar to that in man, thus the rabbit can be used as a suitable alternative for the studies of penile erection, and (2) cAMP is mediated in PGE1-induced relaxation of the rabbit corpus cavernosum, and the cAMP system only participates partially in penile erection.