Sung Han Kim

Overexpression of ERG and Wild-Type PTEN Are Associated with Favorable Clinical Prognosis and Low Biochemical Recurrence in Prostate Cancer

Objectives The aim of this study was to investigate the expression of two commonly altered genes ERG and PTEN in prostate cancer (PC) and evaluate their prognostic significance. Despite conflicting published results, TMPRSS2-ERG gene fusion and PTEN loss are generally considered unfavorable markers for PC progression. Materials and Methods Of the 762 prostatic adenocarcinoma specimens obtained from radical prostatectomy, 613 without neoadjuvant hormone therapy were included in tissue microarrays for quantitatively assessment of ERG and PTEN expression via immunohistochemistry. Statistical analysis of the association between such expression and clinicopathological parameters, including clinical prognosis, was performed with a p-value of <0.05 considered significant. Results During a median follow-up period of 44.0 months, 132 (21.5%) patients developed biochemical recurrence (BCR). ERG overexpression and PTEN loss were observed in 145 (23.7%) and 253 (41.3%) cases, respectively. BCR-free survival was significantly better in patients with ERG overexpression (p=0.005), but unfavorable among those with PTEN loss (p=0.142). Sub-group analysis revealed that patients with PTEN loss and negative ERG expression had the worst BCR-free survival outcome (p=0.021). Furthermore, multivariate analysis identified prostate-specific antigen level (≥10 ng/mL), Gleason score (>6), pathologic T stage (≥T3), positive surgical margin, and extraprostatic capsule extension as significant risk factors for BCR (p<0.05). Conclusions Our results indicated that ERG overexpression was associated with favorable BCR-free survival after radical prostatectomy for PC, whereas PTEN loss was with unfavorable outcomes.

Incidence and Risk Factors of Chronic Kidney Disease in Korean Patients with T1a Renal Cell Carcinoma Before and After Radical or Partial Nephrectomy

OBJECTIVEnThe aim of the study was to investigate the incidence of chronic kidney disease in patients with T1a renal cell carcinoma both before and after partial or radical nephrectomy, and to assess risk factors for chronic kidney disease.nnnMETHODSnFrom January 2001 to December 2011, 1928 patients with a single renal mass ≤4 cm undergoing partial nephrectomy or radical nephrectomy with the existence of a normal contralateral kidney were retrospectively reviewed for the evaluation of preoperative chronic kidney disease, and reviewed only 1676 patients for the postoperative chronic kidney disease. The estimated glomerular filtration rates were used to define chronic kidney disease <60 ml/min/1.73 m(2) by the Modification of Diet in Renal Disease equation. Demographics and clinicopathological parameters were evaluated to determine the risk factors with the development of chronic kidney disease both before and after surgery.nnnRESULTSnChronic kidney disease was found preoperatively in 10.0% (n = 192) of patients; 16.1% (n = 269) of patients developed chronic kidney disease postoperatively, including 102 (6.1%) chronic kidney disease patients >65 years of age. Between the non-chronic kidney disease and chronic kidney disease patients, male gender (odds ratio 3.55 vs. 3.78, respectively) and diagnostic age (odds ratio 1.04 vs. 1.05) were significantly distinctive common risk factors for chronic kidney disease both before and after surgery (P < 0.002). In addition, hypertension (odds ratio 0.46), serum albumin (odds ratio 0.23) and calcium (odds ratio 2.06) were significant as preoperative risk factors (P < 0.015), and preoperative serum creatinine (odds ratio 1.90) and surgical type (partial nephrectomy or radical nephrectomy; odds ratio 11.89) were significant as postoperative risk factors (P < 0.030).nnnCONCLUSIONSnOld, male hypertensive patients with a small renal mass would be better candidates for partial nephrectomy to prevent postoperative chronic kidney disease.

Detection of human papillomavirus infection and p16 immunohistochemistry expression in bladder cancer with squamous differentiation.

Objectives To determine the potential association between HPV infection and the squamous cell component of urothelial carcinoma (UC) of the bladder and to validate p16 overexpression as a surrogate marker for HPV infection in these cancers among Koreans. Methods We analyzed the presence of HPV infection using an HPV-DNA chip and the expression of p16 using immunohistochemistry in 47 subjects between July 2001 and March 2011. The study group (nu200a=u200a35) included patients with squamous differentiation of UC of the bladder. The control group (nu200a=u200a12) included patients with squamous metaplasia of the bladder. Results Baseline characteristics of control and study groups were similar. HPV DNA detection rates were approximately 2-fold higher in the study than the control group (17.1% [6/35] versus 8.3% [1/12], respectively), but the difference was not statistically significant. P16 overexpression was detected in 16/35 (45.7%) study group and 1/12 (8.3%) control group samples (pu200a=u200a0.034). Both HPV-positivity and p16 overexpression were present in 3/35 (8.8%) study group samples, but none of the control group (pu200a=u200a0.295). In the study group, the percentage of HPV-positive cases who were non-smokers was 2-fold higher than the percentage of HPV-negative cases who were non-smokers (66.7% [4/6] versus 31.0% [9/29], respectively); however, statistical significance was not achieved due to the small sample size. Conclusions HPV infection may be associated with UC of the bladder with squamous differentiation, especially in non-smokers. However, p16 expression does not appear to be a strong surrogate marker for evidence of HPV infection in this type of cancer.

Trends in the Use of Chemotherapy before and after Radical Cystectomy in Patients with Muscle-invasive Bladder Cancer in Korea.

We investigated trends in perioperative chemotherapy use, and determined factors associated with neoadjuvant chemotherapy (NAC) and adjuvant chemotherapy (AC) use in Korean patients with muscle-invasive bladder cancer (MIBC). We recruited 1,324 patients who had MIBC without nodal invasion or metastases and had undergone radical cystectomies (RC) between 2003 and 2013. The studys cut-off time for AC was three months after surgery, and the studys timespan was divided into three periods based on NAC use, namely, 2003-2005, 2006-2009, and 2010-2013. Complete remission was defined as histologically confirmed T0N0M0 after RC. NAC and AC were administered to 7.3% and 18.1% of the patients, respectively. The median time interval between completing NAC and undergoing RC was 32 days and the mean number of cycles was 3.2. The median time interval between RC and AC was 43 days and the mean number of cycles was 4.1. Gemcitabine and cisplatin were most frequently used in combination for NAC (49.0%) and AC (74.9%). NAC use increased significantly from 4.6% between 2003 and 2005 to 8.4% between 2010 and 2013 (P < 0.05), but AC use did not increase. Only 1.9% of patients received NAC and AC. Complete remission after NAC was achieved in 12 patients (12.5%). Multivariable modeling revealed that an advanced age, the earliest time period analyzed, and clinical tumor stage ≤ cT2 bladder cancer were negatively associated with NAC use (P < 0.05). While NAC use has slowly increased over time, it remains an underutilized therapeutic approach in Korean clinical practice.

Isolation and characterization of a dominant dwarf gene, d-h, in rice.

Plant height is an important agronomic trait that affects grain yield. Previously, we reported a novel semi-dominant dwarfmutant, HD1, derived from chemical mutagenesis using N-methyl-N-nitrosourea (MNU) on a japonica rice cultivar, Hwacheong. In this study, we cloned the gene responsible for the dwarf mutant using a map-based approach. Fine mapping revealed that the mutant gene was located on the short arm of chromosome 1 in a 48 kb region. Sequencing of the candidate genes and rapid amplification of cDNA ends-polymerase chain reaction (RACE-PCR) analysis identified the gene, d-h, which encodes a protein of unknown function but whose sequence is conserved in other cereal crops. Real-time (RT)-PCR analysis and promoter activity assays showed that the d-h gene was primarily expressed in the nodes and the panicle. In the HD1 plant, the d-h gene was found to carry a 63-bp deletion in the ORF region that was subsequently confirmed by transgenic experiments to be directly responsible for the gain-of-function phenotype observed in the mutant. Since the mutant plants exhibit a defect in GA response, but not in the GA synthetic pathway, it appears that the d-h gene may be involved in a GA signaling pathway.

The prognostic value of BAP1, PBRM1, pS6, PTEN, TGase2, PD-L1, CA9, PSMA, and Ki-67 tissue markers in localized renal cell carcinoma: A retrospective study of tissue microarrays using immunohistochemistry

Objective To assess the prognostic roles of BAP1, PBRM1, pS6, PTEN, TGase2, PD-L1, CA9, PSMA, and Ki-67 tissue biomarkers in localized renal cell carcinoma (RCC). Methods Patients who underwent a nephrectomy during 1992–2015 and had a primary specimen of their kidney tumor were included. The nine tissue biomarkers were immunohistochemically stained on tissue microarrays of RCC, and the semi-quantitative H-score, including intensity score, was used to grade the sample. The Cox proportional hazards model was used to evaluate tissue markers significant for overall survival (OS), cancer-specific survival (CSS), and recurrence-free survival (RFS) after adjusting for significant clinicopathological parameters. Results Samples from 351 RCC patients were included. The mean age of the patients was 53.9 years; the rates of pathologic T1-2/≥T3 stage, Fuhrman 1+2/3+4 grade, recurrence, and death were 269/65(80.5/19.5%), 222/107 (67.5/32.5%), 6.6%, and 10.5%, respectively. Median OS, CSS, and RFS were 220.6, 220.6, and 147.1 months, respectively. The multivariable analysis showed that pathologic T stage and Fuhrman nuclear grade were significantly associated with OS and CSS. Pathologic T stage and tumor size were associated with RFS. After adjusting for these significant prognostic clinicopathological factors, Ki-67 was significantly associated with OS (hazard ratio [HR], 2.7), CSS (HR, 3.82), and RFS (HR, 4.85) and pS6 was associated with CSS (HR, 8.63) and RFS (HR, 8.51) in the multivariable model (p<0.05). Conclusion pS6 and Ki-67 are significant prognostic factors of RCC; however, BAP1, PBRM1, TGase 2, PD-L1, CA9, PTEN loss, and PSMA markers did not show this association.

Baseline Chronic Kidney Disease and Ischemic Method of Partial Nephrectomy Are Important Factors for the Short- and Long-Term Deterioration in Renal Function for Renal Cell Carcinoma Staged T1-T2: A Retrospective Single Center Study

The renal functions of 215 patients (24 with benign renal mass, the rest with RCC staged T1-T2) who underwent partial nephrectomy (PN) between 2003 and 2014 were evaluated to identify predictors of short- and long-term deterioration in renal function after PN among renal cell carcinoma (RCC) patients with or without preoperative predisposition to chronic kidney disease (CKD) and among patients with benign renal mass. The 1- and 5-year predictive factors for de novo CKD were statistically analyzed. The incidence of de novo CKD differed significantly (p < 0.001) among patients with benign renal mass, those with RCC but no preoperative CKD predisposition, and those with RCC combined with preoperative CKD predisposition. Independent predictors for de novo CKD at 1 year postoperatively included intraoperative ischemic method, ECOG score, elevated albumin levels, male sex, and smoking exposure (in pack-years). Predictors for de novo CKD at 5 years postoperatively included hypertension, high preoperative albumin levels, De Ritis ratio (aspartate aminotransferase/alanine aminotransferase ratio), smoking exposure, and preoperative predisposition to CKD. Preoperative predisposition to CKD and ischemic method applied during PN, along with other preoperative parameters, were important factors affecting postoperative renal function deterioration in patients with T1-T2 RCC.

Primary Tumor Characteristics Are Important Prognostic Factors for Sorafenib-Treated Patients with Metastatic Renal Cell Carcinoma: A Retrospective Multicenter Study

We aimed to identify prognostic factors associated with progression-free survival (PFS) and overall survival (OS) in metastatic renal cell carcinoma (mRCC) patients treated with sorafenib. We investigated 177 patients, including 116 who received sorafenib as first-line therapy, using the Cox regression model. During a median follow-up period of 19.2 months, the PFS and OS were 6.4 and 32.6 months among all patients and 7.4 months and undetermined for first-line sorafenib-treated patients, respectively. Clinical T3-4 stage (hazard ratio [HR] 2.56) and a primary tumor size >7u2009cm (HR 0.34) were significant prognostic factors for PFS among all patients, as were tumor size >7u2009cm (HR 0.12), collecting system invasion (HR 5.67), and tumor necrosis (HR 4.11) for OS (p < 0.05). In first-line sorafenib-treated patients, ≥4 metastatic lesions (HR 28.57), clinical T3-4 stage (HR 4.34), collecting system invasion (univariate analysis HR 2.11; multivariate analysis HR 0.07), lymphovascular invasion (HR 13.35), and tumor necrosis (HR 6.69) were significant prognosticators of PFS, as were bone metastasis (HR 5.49) and clinical T3-4 stages (HR 4.1) for OS (p < 0.05). Our study thus identified a number of primary tumor-related characteristics as important prognostic factors in sorafenib-treated mRCC patients.

Overexpression of BRCA1 or BRCA2 in prostatectomy specimens is predictive of biochemical recurrence after radical prostatectomy

To investigate the protein expressions of breast cancer 1 (BRCA1) and 2 (BRCA2) in prostatectomy specimens of localized prostate cancer (PC) patients, along with their associations with cancer characteristics and prognosis.

Comparison of bone mineral loss by combined androgen block agonist versus GnRH in patients with prostate cancer: A 12 month-prospective observational study

The multi-centre, prospective, observational study was designed to examine the efficacy of continuous combined androgen block (CAB) vs. GnRH agonist monotherapy in terms of bone mineral density (BMD) change during 12 months post-androgen deprivation therapy (ADT) in Asian prostate cancer patients. Multiple regression analysis and estimated the 10-year probability of major fractures among the patients with Fracture Risk Assessment Tool were conducted to investigate the underlying factors affecting BMD. Paired t-test to evaluate the change of BMD from baseline to 12 month, and two sample t-test to examine the difference of BMD changes were used between two groups. BMD significantly decreased in both the CAB and GnRH groups, with no group wise differences. The proportion of osteopenia or osteoporosis was slightly increased after the 12-month post-ADT. Ten-year probability of hip fracture and major osteoporotic fracture was approximately 3% and 5%, respectively. In conclusion, a significant decrease of BMD by 12-month ADT was observed without any differences between the two groups, whereas ADT-related BMD loss did not induce detrimental effects on bone health in terms of increased bone fracture risk. This was the first prospective study on BMD changes as a predictor of fracture during ADT in an Asian population.