Transcriptional Regulation of N-Acetylglutamate Synthase

The urea cycle converts toxic ammonia to urea within the liver of mammals. At least 6 enzymes are required for ureagenesis, which correlates with dietary protein intake. The transcription of urea cycle genes is, at least in part, regulated by glucocorticoid and glucagon hormone signaling pathways. N-acetylglutamate synthase (NAGS) produces a unique cofactor, N-acetylglutamate (NAG), that is essential for the catalytic function of the first and rate-limiting enzyme of ureagenesis, carbamyl phosphate synthetase 1 (CPS1). However, despite the important role of NAGS in ammonia removal, little is known about the mechanisms of its regulation. We identified two regions of high conservation upstream of the translation start of the NAGS gene. Reporter assays confirmed that these regions represent promoter and enhancer and that the enhancer is tissue specific. Within the promoter, we identified multiple transcription start sites that differed between liver and small intestine. Several transcription factor binding motifs were conserved within the promoter and enhancer regions while a TATA-box motif was absent. DNA-protein pull-down assays and chromatin immunoprecipitation confirmed binding of Sp1 and CREB, but not C/EBP in the promoter and HNF-1 and NF-Y, but not SMAD3 or AP-2 in the enhancer. The functional importance of these motifs was demonstrated by decreased transcription of reporter constructs following mutagenesis of each motif. The presented data strongly suggest that Sp1, CREB, HNF-1, and NF-Y, that are known to be responsive to hormones and diet, regulate NAGS transcription. This provides molecular mechanism of regulation of ureagenesis in response to hormonal and dietary changes

The possible functions of duplicated ets (GGAA) motifs located near transcription start sites of various human genes

Transcription is one of the most fundamental nuclear functions and is an enzyme complex-mediated reaction that converts DNA sequences into mRNA. Analyzing DNA sequences of 5′-flanking regions of several human genes that respond to 12-O-tetradecanoyl-phorbol-13-acetate (TPA) in HL-60 cells, we have identified that the ets (GGAA) motifs are duplicated, overlapped, or clustered within a 500-bp distance from the most 5′-upstream region of the cDNA. Multiple protein factors including Ets family proteins are known to recognize and bind to the GGAA containing sequences. In addition, it has been reported that the ets motifs play important roles in regulation of various promoters. Here, we propose a molecular mechanism, defined by the presence of duplication and multiplication of the GGAA motifs, that is responsible for the initiation of transcription of several genes and for the recruitment of binding proteins to the transcription start site (TSS) of TATA-less promoters

Prostatic urethral angle might be a predictor of treatment efficacy of α-blockers in men with lower urinary tract symptoms

Chen-Pang Hou,1 Chien-Lun Chen,1 Yu-Hsiang Lin,1 Yu-Lun Tsai,1 Phei-Lang Chang,1 Horng-Heng Juang,2 Ke-Hung Tsui11Department of Urology, Chang Gung Memorial Hospital, College of Medicine, Chang Gung University, 2Department of Anatomy, College of Medicine, Chang Gung University, Taoyuan, Taiwan, Republic of ChinaPurpose: We investigated the association of the prostatic urethral angle (PUA) with peak urinary flow rate (Qmax) and the severity of lower urinary tract symptoms (LUTS) on the aging male. We also evaluated the effect of the PUA on the treatment efficacy of tamsulosin on men with LUTS.Materials and methods: The records were obtained from a prospective database for first-visit male patients with LUTS in the outpatient department of our institution. These patients underwent a detailed physical examination and taking of medical history. A transrectal ultrasound was performed on these patients. The prostate size, length of intravesical prostatic protrusion (IPP), PUA, and International Prostate Symptom Score (IPSS) of the patients were evaluated. Uroflowmetry and a bladder scan for residual urine were also performed on every patient. Tamsulosin 0.2 mg per day was prescribed. The IPSS and uroflowmetry were reevaluated after they had received treatment for 3 months.Results: A total of 178 patients were included, and 149 of them completed this cohort study. The mean PUA was 48.32°±13.74°. The mean prostate volume was 39.19±20.87 mL, and the mean IPP was 5.67±7.85 mm. On multivariate linear regression analysis, the PUA was independently associated with the IPSS (P<0.001), Qmax (P=0.004), post-treatment IPSS change (P=0.032), and post-treatment Qmax change (P<0.001). However, the prostate volume and IPP were not associated with these clinical items.Conclusion: The PUA is significantly associated with Qmax and IPSS in men with LUTS. The PUA is also inversely correlated with changes in Qmax and IPSS after tamsulosin treatment. Namely, the PUA might be a predictor for the treatment efficacy of α-blockers in aging men with LUTS.Keywords: prostatic urethral, prostate, International Prostate Symptom Score, benign prostatic hyperplasi

Prostatectomy using different lasers for the treatment of benign prostate hyperplasia in aging males

Wei-Chang Lee,1,* Yu-Hsiang Lin,1,* Chen-Pang Hou,1 Phei-Lang Chang,1 Chien-Lun Chen,1 Horng-Heng Juang,2 Ke-Hung Tsui1 1Department of Urology, Chang Gung Memorial Hospital-Linko and Chang Gung University, College of Medicine, Taiwan, 2Department of Anatomy, College of Medicine, Chang Gung University, Kweishan-Shan, Taoyuan, Taiwan, Republic of China *These authors contributed equally to this work Purpose: Endoscopic lasers have become a treatment option for benign prostate hyperplasia (BPH). The study reported here sought to elucidate the benefits and drawbacks of different laser systems in the treatment of patients with BPH. Methods: The study enrolled 741 patients diagnosed with lower urinary tract symptoms secondary to BPH during the period January 2005 to December 2011. The techniques used in the study were photoselective vaporization of the prostate, thulium laser prostatectomy, and diode laser prostatectomy. Patients were assigned to one of three groups according to the type of laser treatment they received. Outcomes were evaluated using the International Prostate Symptom Score (IPSS), quality of life, maximal urinary flow rate, post-voiding residual urine volume, and prostate-specific antigen (PSA) level. Results: The baseline characteristics of patients who received diode laser prostatectomy show a significant elevated risk and high American Society of Anesthesiology score (P=0.001). Operative time and catheter removal time differed significantly between the three groups (P=0.001). No cases were converted to transurethral resection of the prostate intraoperatively due to bleeding (P=0.142). Among the three groups, there were no significant differences in maximal flow rate, lower post-void residual urine, and postoperative PSA level during the entire follow-up period (P<0.05). Further, no significant differences in postoperative IPSS, quality of life, or bladder neck contracture (P=0.23) were observed. However, a significant difference was observed with regard to prolonged use of Foley catheters and prolonged hospital stay among patients in the diode laser group (P=0.001). Conclusion: Laser prostatectomies are effective in dealing with lower urinary tract symptoms. Early subjective functional results (maximal flow rate, IPSS, and post-void residual urine) appeared the same as those obtained following laser prostatectomy. Thus, it appears that lasers are safe and effective as long as the patients are carefully selected for treatment. Keywords: prostate gland, laser prostatectomy, diode laser, thulium laser, photoselective vaporization of the prostat

Immediate results and long-term cardiovascular outcomes of endovascular therapy in octogenarians and nonoctogenarians with peripheral arterial diseases

Hsuan-Li Huang,1 Jyh-Ming Jimmy Juang,2 Hsin-Hua Chou,1,3 Chien-An Hsieh,1 Shih-Jung Jang,1 Shih-Tsung Cheng,1,3 Yu-Lin Ko1,3 1Division of Cardiology, Department of Internal Medicine, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, New Taipei City, 2Cardiovascular Center and Division of Cardiology, Department of Internal Medicine, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei, 3School of Medicine, Tzu Chi University, Hualien, Taiwan Purpose: To investigate the clinical outcomes of endovascular therapy (EVT) in octogenarians and nonoctogenarians with peripheral arterial disease. Methods: A retrospective analysis of 511 patients (654 affected legs) who underwent EVT between July 2005 and December 2013 was conducted in a prospectively maintained database. Immediate results and long-term vascular outcomes were analyzed and compared between octogenarians and nonoctogenarians. Results: Octogenarians were more likely to be female and have atrial fibrillation (AF), whereas nonoctogenarians had higher rates of obesity, claudication, and medical comorbidities. There were no differences in the rates of EVT success, 30-day major adverse vascular events, and 6-month functional improvement between groups. Over the 10-year follow-up period, the rates of 3-year limb salvage, sustained clinical success, freedom from major cerebrovascular and cardiovascular events, and composite vascular events were similar between groups, but the survival rate was better in nonoctogenarians than in octogenarians (73% vs 63%, respectively, P=0.004). In Cox regression analysis, dependence on dialysis and AF were significant predictors of death (odds ratio [OR] 4.44 in dialyzed and 2.83 in AF patients), major cerebrovascular and cardiovascular events (OR 3.49 and 2.45), and composite vascular events (OR 3.14 and 2.25). Conclusion: EVT in octogenarians was feasible, without an increased risk of periprocedural complications. The rates of limb salvage, sustained clinical success, and long-term vascular events were comparable between groups. Dialysis dependence and AF are independent predictors for poor prognosis in patients with peripheral arterial disease. However, these observations require further confirmation in larger scale studies. Keywords: peripheral artery disease, octogenarians, endovascular therapy, cardiovascular outcomes, dialysis, atrial fibrillatio

Is diabetes mellitus associated with clinical outcomes in aging males treated with transurethral resection of prostate for bladder outlet obstruction: implications from Taiwan Nationwide Population-Based Cohort Study

Yu-Hsiang Lin,1–3,* Chen-Pang Hou,1,2,* Tien-Hsing Chen,2,4 Horng-Heng Juang,5 Phei-Lang Chang,1,2 Pei-Shan Yang,1,2 Yu-Sheng Lin,2,6 Chien-Lun Chen,1,2 Ke-Hung Tsui1,2 1Department of Urology, Chang Gung Memorial Hospital – Linkou, 2School of Medicine, 3Graduate Institute of Clinical Medical Sciences, College of Medicine, Chang Gung University, 4Division of Cardiology, Department of Internal Medicine, Chang Gung Memorial Hospital, Keelung, 5Department of Anatomy, School of Medicine, Chang Gung University, Kwei-shan, Tao-Yuan, 6Division of Cardiology, Department of Internal Medicine, Chang Gung Memorial Hospital, Chiayi, Taiwan, Republic of China *These authors contributed equally to this work Purpose: We assessed the lower urinary tract symptoms (LUTSs) and clinical outcomes between diabetes mellitus (DM) patients and non-diabetic (non-DM) patients receiving transurethral resection of prostate (TUR-P). Methods: This analysis was a retrospective cohort study using 13 years (2000–2012) of claims data from Taiwan’s National Health Insurance Research Database (NHIRD). A total of 4,887 patients who had persistent LUTSs and underwent TUR-P for prostate enlargement (benign prostate enlargement [BPE]) were enrolled and divided into two groups: DM and non-DM groups. The patients’ characteristics, postoperative clinical outcomes, and the medication records after TUR-P were compared. Chi-square test was used for categorical variables and independent samples t-test for continuous variables. Multivariable logistic regression analysis was used to compare the risk of postoperative outcomes. Finally, we estimated the medication-free survival rate after TUR-P using Kaplan–Meier method and compared it between study groups using log-rank test. Results: DM group patients had a higher prevalence of comorbidities. Postoperatively, the DM group had lower rates of urinary tract infection (UTI; odds ratio [OR], 0.78; P=0.009) and higher rates of urinary retention requiring catheterization (OR, 1.35; P=0.01) within 1 month after TUR-P. A higher proportion of patients with DM took anti-muscarinics (OR, 1.23; P=0.032) within the first 3 months and α-blockers (OR, 1.18; P=0.049) during 3–12 months after receiving TUR-P. Overall, the DM group patients had a worse postoperative medication-free survival compared to that of non-DM group patients (95% confidence interval [95% CI], 1.14; P=0.005). Conclusion: DM patients require higher rates of continuing medication after TUR-P, especially anti-muscarinics in 3 months postoperatively and alpha-blocker after 3 months postoperatively. DM patients also had higher incidence of urine retention after surgery. DM patients had relatively poor treatment outcomes compared to DM-free patients. Keywords: benign prostate hyperplasia, infection, overactive bladder, prostatectomy, urinary tract infection, lower urinary tract symptom

MART-10, a newly synthesized vitamin D analog, represses metastatic potential of head and neck squamous carcinoma cells

Shih-Wei Yang,1,* Chi-Ying Tsai,2,* Yi-Chun Pan,3 Chun-Nan Yeh,4 Jong-Hwei S Pang,5 Masashi Takano,6 Atsushi Kittaka,6 Horng-Heng Juang,7 Tai C Chen,8 Kun-Chun Chiang4,9 1Department of Otolaryngology – Head and Neck Surgery, Chang Gung Memorial Hospital, Keelung, 2Department of Oral and Maxillofacial Surgery, Chang Gung Memorial Hospital, Taoyuan, 3Department of General Dentistry, Chang Gung Memorial Hospital, Chang Gung University, Keelung, 4General Surgery Department, Chang Gung Memorial Hospital, Keelung, 5Graduate Institute of Clinical Medical Sciences, College of Medicine, Chang Gung University, Taoyuan, Taiwan, Republic of China; 6Faculty of Pharmaceutical Sciences, Teikyo University, Tokyo, Japan; 7Department of Anatomy, College of Medicine, Chang Gung University, Taoyuan, Taiwan, Republic of China; 8Endocrine Core Laboratory, Boston University School of Medicine, Boston, MA, USA; 9Zebrafish Center, Chang Gung Memorial Hospital, Keelung, Taiwan, Republic of China *These authors contributed equally to this work Abstract: Even with multidisciplinary treatment, the prognosis and quality of life of patients diagnosed with head and neck squamous cell carcinoma (HNSCC) are still not satisfactory. Previously, 19-Nor-2α-(3-hydroxypropyl)-1α,25(OH)2D3 (MART-10), the new brand 1α,25(OH)2D3 analog, has been demonstrated to be an effective drug to inhibit HNSCC growth in vitro. Since most cancer patients die of metastasis, in this study, the antimetastatic effect of MART-10 on HNSCC was investigated. Our results reveal that both 1α,25(OH)2D3 and MART-10 effectively repressed the migration and invasion of HNSCC cells, with MART-10 being much more potent than 1α,25(OH)2D3. The antimetastatic effect of 1α,25(OH)2D3 and MART-10 was mediated by attenuation of epithelial–mesenchymal transition (EMT), which was supported by the finding that the expression of EMT-inducing transcriptional factors, Sail and Twist, was inhibited by 1α,25(OH)2D3 and MART-10. The upregulation of E-cadherin and downregulation of N-cadherin in FaDu cells induced by both drugs further confirmed the repression of EMT. In addition, 1α,25(OH)2D3 and MART-10 treatment inhibited intracellular MMP-9 expression and extracellular MMP activity in FaDu cells. Collectively, our results suggest that the less-calcemia 1α,25(OH)2D3 analog, MART-10, is a promising drug for HNSCC treatment. Further clinical studies are warranted. Keywords: EMT, head and neck cancer, vitamin D analog, metastasis, MART-1