Ky Hyun Chung

Identification of Proteins Differentially Expressed in the Conventional Renal Cell Carcinoma by Proteomic Analysis

Renal cell carcinoma (RCC) is one of the most malignant tumors in urology, and due to its insidious onset patients frequently have advanced disease at the time of clinical presentation. Thus, early detection is crucial in management of RCC. To identify tumor specific proteins of RCC, we employed proteomic analysis. We prepared proteins from conventional RCC and the corresponding normal kidney tissues from seven patients with conventional RCC. The expression of proteins was determined by silver stain after two-dimensional polyacrylamide gel electrophoresis (2D-PAGE). The overall protein expression patterns in the RCC and the normal kidney tissues were quite similar except some areas. Of 66 differentially expressed protein spots (p<0.05 by Student t-test), 8 different proteins from 11 spots were identified by MALDI-TOF-MS. The expression of the following proteins was repressed (p<0.05); aminoacylase-1, enoyl-CoA hydratase, aldehyde reductase, tropomyosin α-4 chain, agmatinase and ketohexokinase. Two proteins, vimentin and α-1 antitrypsin precursor, were dominantly expressed in RCC (p<0.05).

Gene Transfer of TRPC6DN (Dominant Negative) Restores Erectile Function in Diabetic Rats

INTRODUCTION Transient receptor potential (TRP) channels play an important role in modulating intracellular Ca(2+) ([Ca(2+)](i)) levels. AIM We examined the hypothesis that overexpression of TRPC6(DN) (dominant negative) may contribute to decreased [Ca(2+)](i) levels in corporal smooth muscle (CSM). We also investigated whether gene transfer of TRPC6(DN) could restore erectile function in diabetic rats. METHODS For the in vitro study, the K(Ca), K(ATP), and TRPC6(DN) channel genes were transferred using cDNA, into cultured human CSM cells and human embryonic kidney cells. For the in vivo study, young adult rats were divided into three groups: normal controls; diabetic controls transfected with vector only; and a diabetic group transfected with pcDNA of the TRPC6(DN) gene. MAIN OUTCOME MEASURES After gene transfer, the effects of reducing [Ca(2+)](i) levels were assessed by Fura-2-based imaging analysis. The intracavernosal pressure (ICP) response to cavernosal nerve stimulation was assessed after intracorporal injection of TRPC6(DN) pcDNA. The transgene expression of the TRPC6(DN) was examined by reverse transcription polymerase chain reaction (RT-PCR) in rats transfected with TRPC6(DN) pcDNA. RESULTS Gene transfer of ion channels effectively reduced [Ca(2+)](i). Among these channels, transfer of the TRPC6(DN) gene resulted in the greatest reduction of [Ca(2+)](i) in human CSM. The mean (+/-standard error of the mean) ratio of ICP to mean arterial pressure (BP) in the gene-transfer rats was 79.4 +/- 2.4% (N = 8). This was significantly higher than that in control rats (55.6 +/- 3.7% [N = 8]), and similar to that in the young control rats (83 +/- 2.2% [N = 12]). The RT-PCR showed expression of TRPC6(DN) genes in the transfected rats. CONCLUSION Gene transfer of TRPC6(DN) not only reduced [Ca(2+)](i) in human CSM but also restored erectile function in diabetic rats. These results suggest that pcDNA transfer of TRPC6(DN) may represent a promising new form of therapy for the treatment of male erectile dysfunction in the future.

Angiomyofibroblastoma-Like Tumor of the Scrotum

Various tumors can occur in the scrotum. Of them, angiomyofibroblastoma-like tumors are very rare mesenchymal tumors. Angiomyofibroblastoma-like tumors cannot be easily differentially diagnosed from other malignant tumors invading the male genital tract on the basis of clinical characteristics and imaging study. Therefore, surgical removal and a histopathologic diagnosis must also be performed.

Stereotactic Body Radiation Therapy for Low- to Intermediate-risk Prostate Adenocarcinoma.

The aim of the present study was to evaluate the efficacy and toxicity of stereotactic body radiation therapy (SBRT) for low- to intermediate-risk prostate adenocarcinoma. Thirty-nine patients were retrospectively reviewed. The SBRT was delivered using the CyberKnife with the fiducial tracking method combined with In-tempo imaging. The gross target volume, which included the prostate only, was delineated on the fused CT/MRI scans. The prescription dose was delivered every other day as 5 fractions of 7.5 Gy. Venous blood was obtained before and after SBRT to assess the prostate-specific antigen (PSA) level. Toxicity was evaluated using the CTCAE, v4.03. The median follow-up time was 30.0 months. The median initial PSA level was 7.7 ng/mL. PSA levels decreased in all patients treated with SBRT, and after 5 months, the median PSA was less than 2 ng/mL. The rate of overall 3-yr actuarial biochemical failure free survival was 93.9%. Acute side effects were generally comparable with those of previous studies. The PSA change and toxicity after SBRT for low- to intermediate-risk prostate adenocarcinoma indicates favorable biochemical responses and tolerable levels of toxicity. Additionally short course treatment may produce cost benefit and convenience to patients.

Complications of Transrectal Ultrasound-Guided Prostate Biopsy: Impact of Prebiopsy Enema

Purpose Transrectal ultrasound (TRUS)-guided biopsy of the prostate is usually safe. However, some patients are hospitalized owing to complications from TRUS biopsy. We identified the risk factors for complications and effective preventive measures for treating complications after TRUS biopsy. Materials and Methods Medical records and radiological images of 1,083 patients who underwent TRUS biopsy of the prostate over 10 years in Gyeongsang National University Hospital were examined retrospectively to investigate the correlation between complications after TRUS biopsy and preventive antibiotics, prebiopsy enema, number of biopsy cores, and pathological findings. Results Complications occurred in 69 patients (6.4%). The complication rates of the 1,008 patients who received antibiotics and the 75 patients who did not were 6.3% and 8.0%, respectively (p=0.469). Complication rates of the pre-biopsy enema group (n=658) and the group without prebiopsy enema (n=425) were 4.7% and 8.9%, respectively (p=0.007). Complication rates of the 6-core biopsy group (n=41) and the 12-core biopsy group (n=955) were 7.3% and 6.3%, respectively (p=0.891). Complication rates of the prostate cancer group (n=306) and the no prostate cancer group (n=713) were 6.2% and 6.6%, respectively (p=0.740). Conclusions A prebiopsy enema was associated with a reduced risk of complications after TRUS biopsy. Preventive antibiotics, number of biopsy cores, and pathological findings did not significantly influence the complication rate.

Pseudoexstrophy of the bladder diagnosed prenatally

Department of Urology, School of Medicine, Gyeongsang National University, JinJu, Korea Department of Surgery, School of Medicine, Gyeongsang National University, JinJu, Korea Department of Obstetrics and Gynecology, School of Medicine, Gyeongsang National University, JinJu, Korea Institute of Health Sciences, School of Medicine, Gyeongsang National University, JinJu, Korea *Correspondence to: Ji Kwon Park. E-mail: obgypjk@gnu.ac.kr

Identification of simvastatin-regulated targets associated with JNK activation in DU145 human prostate cancer cell death signaling

The results of this study show that c-Jun N-terminal kinase (JNK) activation was associated with the enhancement of docetaxel-induced cytotoxicity by simvastatin in DU145 human prostate cancer cells. To better understand the basic molecular mechanisms, we investigated simvastatin-regulated targets during simvastatin-induced cell death in DU145 cells using two-dimensional (2D) proteomic analysis. Thus, vimentin, Ras-related protein Rab-1B (RAB1B), cytoplasmic hydroxymethylglutaryl-CoA synthase (cHMGCS), thioredoxin domain-containing protein 5 (TXNDC5), heterogeneous nuclear ribonucleoprotein K (hnRNP K), N-myc downstream-regulated gene 1 (NDRG1), and isopentenyl-diphosphate Delta-isomerase 1 (IDI1) protein spots were identified as simvastatin-regulated targets involved in DU145 cell death signaling pathways. Moreover, the JNK inhibitor SP600125 significantly inhibited the upregulation of NDRG1 and IDI protein levels by combination treatment of docetaxel and simvastatin. These results suggest that NDRG1 and IDI could at least play an important role in DU145 cell death signaling as simvastatin-regulated targets associated with JNK activation.

Proteomic analysis of novel targets associated with the enhancement of TrkA-induced SK-N-MC cancer cell death caused by NGF.

Nerve growth factor (NGF) is known to regulate both cancer cell survival and death signaling, depending on the cellular circumstances, in various cell types. In this study, we showed that NGF strongly upregulated the protein level of tropomyosin-related kinase A (TrkA) in TrkA-inducible SK-N-MC cancer cells, resulting in increases in various TrkA-dependent cellular processes, including the phosphorylation of c-Jun N-terminal kinase (JNK) and caspase-8 cleavage. In addition, NGF enhanced TrkA-induced morphological changes and cell death, and this effect was significantly suppressed by the JNK inhibitor SP600125, but not by the phosphatidylinositol 3-kinase (PI3K) inhibitor wortmannin. To investigate novel targets associated with the enhancement of TrkA-induced SK-N-MC cell death caused by NGF, we performed Coomassie Brilliant Blue staining and two-dimensional (2D) proteomic analysis in TrkA-inducible SK-N-MC cells. We identified 31 protein spots that were either greatly upregulated or downregulated by TrkA during NGF treatment using matrix-associated laser desorption/ionization time of flight/time of flight mass spectrometry, and we analyzed the effects of SP600125 and wortmannin on the spots. Interestingly, 11 protein spots, including heterogeneous nuclear ribonucleoprotein K (hnRNP K), lamin B1 and TAR DNA-binding protein (TDP43), were significantly influenced by SP600125, but not by wortmannin. Moreover, the NGF/TrkA-dependent inhibition of cell viability was significantly enhanced by knockdown of hnRNP K using small interfering RNA, demonstrating that hnRNP K is a novel target associated with the regulation of TrkA-dependent SK-N-MC cancer cell death enhanced by NGF.

Efficacy of Long-Term Daily Dosage of Alfuzosin 10 mg upon Sexual Function of Benign Prostatic Hypertrophy Patients: Two-Year Prospective Observational Study.

Purpose To identify sexual function improvement associated with alfuzosin (10 mg daily for 2 years). Materials and Methods We enrolled 30 men with lower urinary tract symptom (LUTS) who visited Gyeongsang National University Hospital between 2010 and 2012. At first visit, urinalysis, prostate specific antigen, transrectal ultrasound, and uroflowmetry were performed. The nternational Prostate Symptom Score (IPSS), quality of life (QoL), International Index of Erectile Function (IIEF), and Male Sexual Health Questionnaire Ejaculation Function Domain (MSHQ-EjFD) questionnaires were administered, and the subjects answered the same questionnaires at 1 month, 6 months, 1 year, and 2 years of follow-up. Results Twelve men completed of the entire study. After administration of alfuzosin, the median IPSS at first visit, 1 month, 6 months, 1 year, and 2 years was 18.00 (interquatile range [IQR]: 14.00~29.75), 20.00 (IQR: 11.50~30.00), 15.50 (IQR: 8.50~25.25), 14.50 (IQR: 9.25~19.50), and 11.50 (IQR: 5.00~17.75), respectively, which showed an improvement. The median QoL at the same times was 4.50 (IQR: 4.00~5.00), 4.50 (IQR: 4.00~5.00), 3.00 (IQR: 2.00~4.00), 3.50 (IQR: 2.25~4.00), and 3.00 (IQR: 1.00~3.00), respectively, and also showed improvement. Likewise, the median IIEF was 36.50 (IQR: 24.50~46.75), 37.50 (IQR: 26.75~47.25), 45.50 (IQR: 35.00~59.75), 48.50 (IQR: 34.75~62.75), and 47.50 (IQR: 43.25~61.00), while the median MSHQ-EjFD was 19.00 (IQR: 12.0~24.75), 19.50 (IQR: 13.50~27.75), 23.00 (IQR: 19.25~32.25), 26.50 (IQR: 18.25~34.50), 27.00 (IQR: 21.50~32.50), respectively, with both showing improvement. Conclusions After administration of alfuzosin (10 mg daily for 2 years), the IPSS, QoL, IIEF, and MSHQ-EjFD all improved significantly. This means long-term administration of 10 mg of alfuzosin daily would be effective not only for LUTS but also erectile function and ejaculation.

Proteomic analysis of SP600125-controlled TrkA-dependent targets in SK-N-MC neuroblastoma cells: Inhibition of TrkA activity by SP600125

The c‐Jun N‐terminal kinase (JNK) is well known to play an important role in cell death signaling of the p75 neurotrophin receptor. However, little has been studied about a role of JNK in the signaling pathways of the tropomyosin‐related kinase A (TrkA) neurotrophin receptor. In this study, we investigated JNK inhibitor SP600125‐controlled TrkA‐dependent targets by proteomic analysis to better understand an involvement of JNK in TrkA‐mediated signaling pathways. PDQuest image analysis and protein identification results showed that hnRNP C1/C2, α‐tubulin, β‐tubulin homolog, actin homolog, and eIF‐5A‐1 protein spots were upregulated by ectopic expression of TrkA, whereas α‐enolase, peroxiredoxin‐6, PROS‐27, HSP70, PP1‐gamma, and PDH E1‐alpha were downregulated by TrkA, and these TrkA‐dependent upregulation and downregulation were significantly suppressed by SP600125. Notably, TrkA largely affected certain PTM(s) but not total protein amounts of the SP600125‐controlled TrkA‐dependent targets. Moreover, SP600125 strongly suppressed TrkA‐mediated tyrosine phosphorylation signaling pathways as well as JNK signaling, indicating that SP600125 could function as a TrkA inhibitor. Taken together, our results suggest that TrkA could play an important role in the cytoskeleton, cell death, cellular processing, and glucose metabolism through activation or inactivation of the SP600125‐controlled TrkA‐dependent targets.