The Effect of Phosphodiesterase 5 Inhibitor on Biochemical Recurrence Following Radical Prostatectomy in Patients with Prostate Cancer

PURPOSE

Recently, controversy exists regarding the oncologic outcomes associated with the use of phosphodi-esterase 5 inhibitor (PDE5i). Therefore, we attempted to verify the effect of PDE5i on biochemical recurrence (BCR) following radical prostatectomy (RP) in patients with prostate cancer (PCa).

MATERIALS AND METHODS

From January 2011 to May 2016, 351 patients who had undergone bilateral neurovas-cular bundle saving and who were confirmed as having pT2N0M0 disease were included in the present study. We divided these patients into three groups: no PDE5i use, PDE5i use on demand , and PDE5i use for rehabilitation. We retrospectively analyzed the effect of PDE5i on BCR of PCa. Mean follow-up period was 34.4 months and mesurement of outcome was whether the patients developed BCR during regular follow-up.

RESULTS

25 (7.1%) patients showed BCR and univariate analysis found no significant differences in BCR between the three groups (5 (6.9%) in no PDE5i use, 8 (9.5%) in PDE5i use on demand, 12 (6.2%) in PDE5i use for rehabili-tation). Multivariable analyses showed that treatment type was not a significant factor for BCR between the groups with no PDE5i use and PDE5i use (HR = 1.34 [0.49-3.70]; P = .573) and between the groups with on demand and rehabilitation use (HR = 1.37 [0.35-5.37]; P = .646). Kaplan-Meier survival curves show that there were no significant differences in PSA recurrence-free survival in three groups (P > .05).

CONCLUSION

Use of PDE5is was not associated with any adverse effects on BCR after RP in patients with PCa.

Efficacy of Androgen Deprivation Therapy in Patients with Metastatic Castration-Resistant Prostate Cancer Receiving Docetaxel-Based Chemotherapy

PURPOSE

The purpose of this study was to determine the comparative effectiveness of androgen deprivation therapy (ADT) combined with docetaxel (DTX)-based chemotherapy in Korean and Japanese castration-resistant prostate cancer (CRPC) patient cohorts.

MATERIALS AND METHODS

Metastatic CRPC patients who underwent more than three DTX-based chemotherapy cycles in Korea and Japan between 2002 and 2017 were retrospectively analyzed and divided into the DTX-only (DTX, n=30) and combination (DTX+ADT, n=46) groups. Progression-free survival (PFS) was calculated as the time from the start of chemotherapy to the occurrence of either disease progression (prostate-specific antigen [PSA] progression or radiographic progression) or death. The primary end point was PFS and the secondary end point was overall survival (OS).

RESULTS

In the DTX and DTX+ADT groups, the median PFS was 6.0 and 11.0 months (log-rank p=0.053). The multivariate Cox regression analysis revealed that the significant predicting factors of PFS were ADT administration (hazard ratio [HR], 0.478; 95% confidence interval [CI], 0.284-0.804; p=0.005) and number of DTX-based chemotherapy cycles (HR, 0.934; 95% CI, 0.899-0.970; p<0.001). In the DTX and DTX+ADT groups, the median OS was 16.0 and 19.5 months (log-rank p=0.825). Through multiple Cox regression analysis, we found that the significant predicting factors of OS were the PSA nadir level (HR, 1.001; 95% CI, 1.000-1.002; p<0.001) and number of DTX-based chemotherapy cycles (HR, 0.932; 95% CI, 0.876-0.991; p=0.024).

CONCLUSIONS

Concurrent DTX-based chemotherapy and ADT may be beneficial compared with DTX-based chemotherapy alone in chemotherapy-naïve metastatic CRPC patients in terms of the PFS, but not the OS.

A Low Geriatric Nutritional Risk Index is Associated with Aggressive Pathologic Characteristics and Poor Survival after Nephrectomy in Clear Renal Cell Carcinoma: A Multicenter Retrospective Study

Purpose: To investigated the prognostic significance of the geriatric nutritional risk index (GNRI) in patients with surgically treated clear cell renal cell carcinoma (ccRCC).Patients and methods: We retrospectively selected 4,591 consecutive patients with surgically treated ccRCC from a multi-institutional Korean collaboration between 1988 and 2015. The clinical significance of the GNRI as a continuous and categorical variable was determined.Results: Preoperative low GNRI was significantly associated with older age, low body mass index, presence of diabetes, poor performance status, and presence of symptoms at diagnosis, as well as pathologic features such as aggressive tumor characteristics including large tumor size, advanced stage, high nuclear grade, lymphovascular invasion, sarcomatous differentiation, and tumor necrosis. A low GNRI was significantly associated with a short recurrence-free survival (RFS) in localized (pT1-2N0M0) ccRCC and cancer-specific survival (CSS) in the entire cohort, and with short RFS and CSS in the subgroup analysis according to age categories (≤65 and >65 years). Multivariate Cox regression analysis showed that preoperative GNRI, as a continuous or categorical variable, was an independent predictor of RFS and CSS.Conclusion: Malnutrition as assessed by the preoperative GNRI is associated with aggressive tumor characteristics and poor survival in patients with surgically treated ccRCC.

Susceptibility of the Index Urinary Tract Infection to Prophylactic Antibiotics Is a Predictive Factor of Breakthrough Urinary Tract Infection in Children with Primary Vesicoureteral Reflux Receiving Continuous Antibiotic Prophylaxis

BACKGROUND

Few studies have reported on breakthrough urinary tract infection (UTI) associated with the susceptibility of index UTI to prophylactic antibiotics in children with primary vesicoureteral reflux (VUR) receiving continuous antibiotic prophylaxis (CAP). We assessed the impact of the susceptibility of index UTI to prophylactic antibiotics in breakthrough UTIs in children with primary VUR receiving CAP.

METHODS

We retrospectively reviewed the medical records of 81 children with primary VUR who were diagnosed after febrile or symptomatic UTI and subsequently received trimethoprim-sulfamethoxazole (TMP-SMX) as CAP between January 2010 and December 2013. We allocated children to a susceptible group or a resistant group based on the susceptibility of index UTI to TMP-SMX. We evaluated patient demographics and clinical outcomes after CAP according to the susceptibility of index UTI to TMP-SMX. Multivariate analysis was used to identify the predictive factors for breakthrough UTI.

RESULTS

Of the 81 children, 42 were classified into the susceptible group and 39 into the resistant group. The proportion of breakthrough UTI was 31.0% (13/42) in the susceptible group and 53.8% (21/39) in the resistant group (P = 0.037). Progression of renal scarring was observed in 0% of children in the susceptible group and 15% in the resistant group (P = 0.053). Multivariate analysis showed that TMP-SMX resistance and initial renal scarring were significant predictors of breakthrough UTI.

CONCLUSION

Susceptibility of index UTI to prophylactic antibiotics is a risk factor of breakthrough UTI and is associated with poor clinical outcomes in children with primary VUR receiving CAP.

Adjuvant axitinib dose modification in renal cell carcinoma (RCC): Analysis of the ATLAS study

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Background: The ATLAS trial compared axitinib vs placebo in patients (pts) with locoregional RCC at risk of recurrence after nephrectomy. ATLAS was stopped due to futility at a pre-planned interim analysis; results showed no difference in disease-free survival (DFS) between the treatment arms. We explored whether pts treated longer with axitinib achieved better outcomes and the impact of axitinib dose reduction or increase on DFS – the trial required dose reduction for toxicity and allowed dose escalation in the event of no or minimal toxicity. Methods: Pts in ATLAS received a maximum of 3 y of study treatment. A landmark analysis was conducted comparing pts treated with axitinib ≤1 y vs > 1 y. Pts who recurred or censored prior to 1 y were excluded. An analysis of daily dose characteristics was undertaken to compare patients whose dose was reduced and whose dose was increased to those with a stable dose of axitinib. Cox proportional hazard model was used for DFS analysis. Toxicity analysis using a 90-day landmark was also conducted. Results: Overall, 264 axitinib-treated pts were included in this analysis. Of these 42 pts were treated for ≤1 y and 222 pts for > 1 y. Pts remaining on axitinib > 1 y vs ≤1 y did not have different DFS (hazard ratio [HR] = 0.572, 95% confidence interval [CI]: 0.247–1.327, P= 0.1874). Pts with dose reduction had longer DFS than those with a stable dose (HR = 0.458, CI: 0.305–0.687, P= 0.0001). Pts with dose increase did not have DFS different to stable dose pts (HR = 1.936, CI: 0.937–3.997, P= 0.0685). No difference in DFS in pts experiencing grade ≥2 adverse events (AEs) vs grade < 2 AEs within 90 d of start of treatment was observed (HR = 0.885, CI: 0.419–1.869, P= 0.7488). Pts experiencing grade ≥3 AEs within 90 d of start of treatment had shorter DFS compared to those that did not (HR = 1.643, CI: 0.963–2.801, P= 0.0653). Conclusions: DFS did not vary based on duration of axitinib treatment, however, pts with dose reductions had longer DFS vs pts with stable dose or dose increases. This difference suggests that there is a relation between axitinib exposure and DFS as seen with sunitinib in the advanced setting and pazopanib in the PROTECT study.

ZNF492 and GPR149 methylation patterns as prognostic markers for clear cell renal cell carcinoma: Array‑based DNA methylation profiling

The present study aimed to identify novel methylation markers of clear cell renal cell carcinoma (ccRCC) using microarray methylation analysis and evaluate their prognostic relevance in patient samples. To identify cancer‑specific methylated biomarkers, microarray profiling of ccRCC samples from our institute (n=12) and The Cancer Genome Atlas (TCGA) database (n=160) were utilized, and the prognostic relevance of candidate genes were investigated in another TCGA dataset (n=153). For validation, pyrosequencing analyses with ccRCC samples from our institute (n=164) and another (n=117) were performed and the potential clinical application of selected biomarkers was examined. We identified 22 CpG island loci that were commonly hypermethylated in ccRCC. Kaplan‑Meier analysis of TCGA data indicated that only 4/22 loci were significantly associated with disease progression. In the internal validation set, Kaplan‑Meier analysis revealed that hypermethylation of two loci, zinc finger protein 492 (ZNF492) and G protein‑coupled receptor 149 (GPR149), was significantly associated with shorter time‑to‑progression. Multivariate Cox regression models revealed that hypermethylation of ZNF492 [hazard ratio (HR), 5.44; P=0.001] and GPR149 (HR, 7.07; P<0.001) may be independent predictors of tumor progression. Similarly, the methylation status of these two genes was significantly associated with poor outcomes in the independent external validation cohort. Collectively, the present study proposed that the novel methylation markers ZNF492 and GPR149 could be independent prognostic indicators in patients with ccRCC.

Trends in clinical, operative, and pathologic characteristics of surgically treated renal mass in a Korean center: A surgical series from 1988 through 2015

Purpose

To analyze trends over a period of 28 years in the clinical, operative, and pathologic characteristics of patients with a renal mass who underwent surgical resection in Korea.

Materials and Methods

Consecutive patients (n=6,231) with a renal mass who underwent surgical resection at eight Korean institutions between 1988 and 2015 were reviewed. Patients were assigned to one of three groups according to the date of surgery: group 1, 1988-1999; group 2, 2000-2009; and group 3, 2010-2015.

Results

Age at the time of surgery, body mass index, smoking status, incidence of diabetes and hypertension, and the number of incidentally identified renal masses increased significantly over time. The proportion of patients undergoing partial nephrectomy (PN) or minimally invasive surgery (MIS) increased sharply during the last two time periods. From 2010, the rate of robot-assisted nephrectomy rose sharply, occurring in 37.8% of MIS cases. Benign pathology was identified in 1.8% and 5.2% of cases in the middle and last periods, respectively; angiomyolipoma was the most common pathology. In later years, tumors were more often localized, although tumor grade increased. Sub-group analysis of small renal masses ≤4 cm revealed similar trends in operative and pathologic characteristics over time.

Conclusions

Between 1988 and 2015, there was a substantial change in the clinical, operative, and histological characteristics of patients who underwent resection of a renal mass in Korea. The most notable changes were stage migration towards localized disease and widespread use of PN and MIS.

A Bioinspired Scaffold with Anti-Inflammatory Magnesium Hydroxide and Decellularized Extracellular Matrix for Renal Tissue Regeneration

Kidney diseases are a worldwide public health issue. Renal tissue regeneration using functional scaffolds with biomaterials has attracted a great deal of attention due to limited donor organ availability. Here, we developed a bioinspired scaffold that can efficiently induce renal tissue regeneration. The bioinspired scaffold was designed with poly(lactide-co-glycolide) (PLGA), magnesium hydroxide (Mg(OH)2), and decellularized renal extracellular matrix (ECM). The Mg(OH)2 inhibited materials-induced inflammatory reactions by neutralizing the acidic microenvironment formed by degradation products of PLGA, and the acellular ECM helped restore the biological function of kidney tissues. When the PLGA/ECM/Mg(OH)2 scaffold was implanted in a partially nephrectomized mouse model, it led to the regeneration of renal glomerular tissue with a low inflammatory response. Finally, the PLGA/ECM/Mg(OH)2 scaffold was able to restore renal function more effectively than the control groups. These results suggest that the bioinspired scaffold can be used as an advanced scaffold platform for renal disease treatment.

Association between De Ritis ratio (aspartate aminotransferase/alanine aminotransferase) and oncological outcomes in bladder cancer patients after radical cystectomy

Background

New biological prognostic predictors have been studied; however, some factors have limited clinical application due to tissue-specific expression and high cost. There is the need for a promising predictive factor that is simple to detect and that is closely linked to oncological outcomes in patients with urothelial bladder cancer (BC) who have undergone radical cystectomy (RC). Therefore, we investigated the clinical prognostic value of the preoperative De Ritis ratio (aspartate aminotransferase/alanine aminotransferase) on oncological outcomes in patients with urothelial BC after RC.

Methods

We retrospectively evaluated clinicopathological data of 118 patients with non-metastatic urothelial BC after RC between 2008 and 2013 at a single center. The association between the De Ritis ratio and clinicopathological findings was assessed. The potential prognostic value of the De Ritis ratio was analyzed using the Kaplan-Meier method, and multivariate Cox analyses were performed to identify the independent predictors of metastasis-free survival, cancer-specific survival, and overall survival.

Results

According to the receiver operating curve of the De Ritis ratio for metastasis, we stratified the patients into 2 groups using a threshold of 1.3. A high De Ritis ratio was more likely to be associated with old age and the female sex. Kaplan-Meier estimates revealed that patients with a high De Ritis ratio had inferior metastasis-free survival, cancer-specific survival, and overall survival outcomes (P = 0.012, 0.024, and 0.022, respectively). Multivariate analysis revealed that a high De Ritis ratio was an independent prognostic factor for metastasis (hazard ratio [HR], 2.389; 95% confidence interval [CI], 1.161–4.914; P = 0.018), cancer-related death (HR, 2.755; 95% CI, 1.214–6.249; P = 0.015), and overall death (HR, 2.761; 95% CI, 1.257–6.067; P = 0.011).

Conclusions

An elevated De Ritis ratio was significantly associated with worse prognosis in patients who underwent RC for urothelial BC. This ratio might further improve the predictive accuracy for prognosis in BC.

Effects of Variant Histology on the Oncologic Outcomes of Patients With Upper Urinary Tract Carcinoma After Radical Nephroureterectomy: A Propensity Score-Matched Analysis

PURPOSE

To determine the prognostic effect of upper tract urothelial carcinoma (UTUC) with variant histology (VH) after radical nephroureterectomy (RNU).

PATIENTS AND METHODS

The data of 1173 patients who received RNU for UTUC without neoadjuvant chemotherapy in 11 institutions between 2002 and 2016 were retrospectively reviewed. A matched propensity score analysis was performed. Clinicopathologic variables, recurrence-free survival (RFS), cancer-specific survival (CSS), and overall survival (OS) were compared between patients with pure UTUC and patients with UTUC and VH. Univariate and multivariate Cox proportional regression models were used to determine the independent variables associated with oncologic outcomes.

RESULTS

UTUC with VH was observed in 93 patients (7.9%). After propensity score matching, UTUC with VH showed no difference in clinicopathologic features compared to pure UTUC; however, it was associated with shorter RFS, CSS, and OS (log rank, P = .011, P = .002, P = .006, respectively). Additionally, the multivariate analysis revealed that VH was independently associated with a poor RFS [hazard ratio (HR) = 1.92; 95% confidence interval (CI), 1.27-2.89; P = .002], CSS (HR = 4.47; 95% CI, 1.99-10.1; P = .001), and OS (HR = 3.00; 95% CI, 1.55-5.78; P = .001). However, the Kaplan-Meier method revealed that differences in RFS, CSS, and OS were not significant in patients who received adjuvant chemotherapy (log rank, P = .562, P = .060, P = .153, respectively).

CONCLUSION

UTUC with VH was independently associated with poor oncologic outcomes in patients with UTUC after RNU. Although patients with UTUC and VH had a poor prognosis compared to patients with pure UTUC, adjuvant chemotherapy would be helpful in improving the survival rates of these patients.

Oncological and functional outcomes following robot-assisted laparoscopic radical prostatectomy at a single institution: a minimum 5-year follow-up

Background

To evaluate mid-term oncological and functional outcomes in patients with prostate cancer treated by robot-assisted laparoscopic radical prostatectomy (RALP) at our institution.

Methods

We retrospectively reviewed the medical records of 128 patients with prostate cancer who underwent RALP at our institution between February 2008 and April 2010. All patients enrolled in this study were followed up for at least 5 years. We analyzed biochemical recurrence (BCR)-free survival using a Kaplan-Meier survival curve analysis and predictive factors for BCR using multivariate Cox regression analysis. Continence recovery rate, defined as no use of urinary pads, was also evaluated.

Results

Based on the D’Amico risk classification, there were 30 low-risk patients (23.4%), 47 intermediate-risk patients (38.8%), and 51 high-risk patients (39.8%), preoperatively. Based on pathological findings, 50.0% of patients (64/128) showed non-organ confined disease (≥T3a) and 26.6% (34/128) had high grade disease (Gleason score ≥8). During a median follow-up period of 71 months (range, 66-78 months), the frequency of BCR was 33.6% (43/128) and the median BCR-free survival was 65.9 (0.4-88.0) months. Multivariate Cox regression analysis revealed that high grade disease (Gleason score ≥8) was an independent predictor for BCR (hazard ratio=4.180, 95% confidence interval=1.02-17.12, p=0.047). In addition, a majority of patients remained continent following the RALP procedure, without the need for additional intervention for post-prostatectomy incontinence.

Conclusion

Our study demonstrated acceptable outcomes following an initial RALP procedure, despite 50% of the patients investigated demonstrating high-risk features associated with non-organ confined disease.

Axitinib versus placebo as an adjuvant treatment of renal cell carcinoma: results from the phase III, randomized ATLAS trial

Background

The ATLAS trial compared axitinib versus placebo in patients with locoregional renal cell carcinoma (RCC) at risk of recurrence after nephrectomy.

Patients and methods

In a phase III, randomized, double-blind trial, patients had >50% clear-cell RCC, had undergone nephrectomy, and had no evidence of macroscopic residual or metastatic disease [independent review committee (IRC) confirmed]. The intent-to-treat population included all randomized patients [≥pT2 and/or N+, any Fuhrman grade (FG), Eastern Cooperative Oncology Group status 0/1]. Patients (stratified by risk group/country) received (1 : 1) oral twice-daily axitinib 5 mg or placebo for ≤3 years, with a 1-year minimum unless recurrence, occurrence of second primary malignancy, significant toxicity, or consent withdrawal. The primary end point was disease-free survival (DFS) per IRC. A prespecified DFS analysis in the highest-risk subpopulation (pT3, FG ≥ 3 or pT4 and/or N+, any T, any FG) was conducted.

Results

A total of 724 patients (363 versus 361, axitinib versus placebo) were randomized from 8 May 2012, to 1 July 2016. The trial was stopped due to futility at a preplanned interim analysis at 203 DFS events. There was no significant difference in DFS per IRC [hazard ratio (HR) = 0.870; 95% confidence interval (CI) : 0.660-1.147; P = 0.3211). In the highest-risk subpopulation, a 36% and 27% reduction in risk of a DFS event (HR; 95% CI) was observed per investigator (0.641; 0.468-0.879; P = 0.0051), and by IRC (0.735; 0.525-1.028; P = 0.0704), respectively. Overall survival data were not mature. Similar adverse events (AEs; 99% versus 92%) and serious AEs (19% versus 14%), but more grade 3/4 AEs (61% versus 30%) were reported for axitinib versus placebo.

Conclusions

ATLAS did not meet its primary end point; however, improvement in DFS per investigator was seen in the highest-risk subpopulation. No new safety signals were reported.

Trial registration number

NCT01599754.

Urinary cell-free microRNA biomarker could discriminate bladder cancer from benign hematuria

The most common symptom of bladder cancer (BC) is hematuria. However, not all patients with hematuria are diagnosed with BC. Here, we explored a novel method to discriminate BC from hematuria under nonmalignant conditions by measuring differences in urinary cell-free microRNA (miRNA) expression between patients with BC and those with hematuria. A multicenter study was performed using 543 urine samples obtained from the National Biobank of Korea, including 326 BC, 174 hematuria and 43 pyuria without cancer. The urinary miR-6124 to miR-4511 ratio was considerably higher in BC than in hematuria or pyuria, and enabled the discrimination of BC from patients with hematuria at a sensitivity of >90% (p < 0.001). Conclusively, the proposed noninvasive diagnostic tool based on the expression ratio of urinary cell-free miR-6124 to miR-4511 can reduce unnecessary cystoscopies in patients with hematuria undergoing evaluation for BC, with a minimal loss in sensitivity for detecting cancer.

Predictive factors for adrenal metastasis in extra-adrenal malignancy patients with solitary adrenal mass

BACKGROUND AND OBJECTIVES

The adrenal gland is a frequent site for metastasis, and a solitary adrenal mass is often observed during staging workup or imaging follow-up in patients with extra-adrenal malignancy. To create an appropriate management plan, it is essential to distinguish between benign adrenal lesions and metastasis in patients with extra-adrenal cancer having solitary adrenal masses. Therefore, here we evaluated the predictive factors for adrenal metastasis in patients with extra-adrenal malignancy having solitary adrenal mass.

MATERIALS AND METHODS

From September 2003 to June 2016, we retrospectively reviewed patients with extra-adrenal malignancy having solitary adrenal mass on a cancer staging workup or follow-up study who subsequently underwent adrenalectomy at our institution. All patients underwent preoperative functional studies; those with positive results were excluded from this study. Characteristics of oncology patients with adrenal mass including age, sex, body mass index, smoking, mass location, mass size, hypertension, diabetes mellitus, precontrast Hounsfield unit (HU), and synchronous or metachronous adrenal mass based on the time of the extra-adrenal cancer diagnosis were analyzed.

RESULTS

Of the total 68 patients with extra-adrenal cancer having solitary adrenal mass, 22 had pathologically confirmed adrenal metastasis. Primary cancers consisted of hepatocellular cell carcinoma (n = 7), renal cell carcinoma (n = 7), lung cancer (n = 4), colon cancer (n = 3), and breast cancer (n = 1). On multivariate analysis, a higher precontrast HU (P = 0.001, odds ratio [OR] = 1.105, 95% confidence interval [CI] = 1.042-1.172), male sex ( P = 0.019, OR = 9.782, 95% CI = 1.462-65.461), and metachronous adrenal mass ( P = 0.007, OR = 11.090, 95% CI = 1.937-63.490) were observed as predictive factors for adrenal metastasis in patients with extra-adrenal cancer having solitary adrenal mass. The cut-off value of precontrast HU to distinguish between metastasis and benign lesions was 36.2 (sensitivity = 81.8%; specificity = 91.3%).

CONCLUSION

High precontrast HU (> 36), male sex, and metachronous adrenal mass are predictive factors for adrenal metastasis in patients with extra-adrenal malignancy having solitary adrenal mass.

Partial versus Radical Nephrectomy for T1-T2 Renal Cell Carcinoma in Patients with Chronic Kidney Disease Stage III: a Multiinstitutional Analysis of Kidney Function and Survival Rate

BACKGROUND

To examine survival rates and renal function after partial nephrectomy (PN) and radical nephrectomy (RN) in patients with chronic kidney disease (CKD).

METHODS

We studied 4,332 patients who underwent PN or RN for pathological T1a-T2N0M0 renal cell carcinoma from 1988 to 2014. Patients were divided into two subgroups of CKD stage I-II and stage III. Kidney function, and survival outcomes were compared between groups.

RESULTS

We included 1,756 patients with CKD I-II and 276 patients with CKD III in the final pair-matched analysis. Kidney function was significantly better preserved in the PN than in the RN group among all patients. However, the beneficial effect of PN on kidney function gradually disappeared over time in CKD III patients. The 5-year overall survival (OS) rates after PN and RN differed in patients with CKD I-II disease (99.4% vs. 96.5%, respectively, P = 0.015). The 5-year OS rates after surgery were not affected by mode of nephrectomy in CKD III patients (97.8% vs. 93.5%, P = 0.103). The 5-year cancer-specific survival rates did not differ between treatment groups in all CKD stage. Cox hazard analysis showed that the operative method was a significant factor for OS in CKD I-II patients (hazard ratio [HR], 0.320; confidence interval [CI], 0.122-0.840; P = 0.021). However, PN was not beneficial in terms of OS in CKD III patients (HR, 0.395; CI, 0.086-1.172; P = 0.117).

CONCLUSION

PN is associated with a higher OS rate and better kidney function in patients with preoperative CKD stage I and II, but not in those with CKD stage III.

A Novel Dorsal Slit Approached Non-Ischemic Partial Nephrectomy Method for a Renal Tissue Regeneration in a Mouse Model

BACKGROUND

Kidney ischemia-reperfusion (IR) via laparotomy is a conventional method for kidney surgery in a mouse model. However, IR, an invasive procedure, can cause serious acute and chronic complications through apoptotic and inflammatory pathways. To avoid these adverse responses, a Non-IR and dorsal slit approach was designed for kidney surgery.

METHODS

Animals were divided into three groups, 1) sham-operated control; 2) IR, Kidney IR via laparotomy; and 3) Non-IR, Non-IR and dorsal slit. The effects of Non-IR method on renal surgery outcomes were verified with respect to animal viability, renal function, apoptosis, inflammation, fibrosis, renal regeneration, and systemic response using histology, immunohistochemistry, real-time polymerase chain reaction, serum chemistry, terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining, and Masson's trichrome staining.

RESULTS

The Non-IR group showed 100% viability with mild elevation of serum blood urea nitrogen and creatinine values at day 1 after surgery, whereas the IR group showed 20% viability and lethal functional abnormality. Histologically, renal tubule epithelial cell injury was evident on day 1 in the IR group, and cellular apoptosis enhanced TUNEL-positive cell number and Fas/caspase-3 and KIM-1/NGAL expression. Inflammation and fibrosis were high in the IR group, with enhanced CD4/CD8-positive T cell infiltration, inflammatory cytokine secretion, and Masson's trichrome stain-positive cell numbers. The Non-IR group showed a suitable microenvironment for renal regeneration with enhanced host cell migration, reduced immune cell influx, and increased expression of renal differentiation-related genes and anti-inflammatory cytokines. The local renal IR influenced distal organ apoptosis and inflammation by releasing circulating pro-inflammatory cytokines.

CONCLUSION

The Non-IR and dorsal slit method for kidney surgery in a mouse model can be an alternative surgical approach for researchers without adverse reactions such as apoptosis, inflammation, fibrosis, functional impairment, and systemic reactions.

Modified Magnesium Hydroxide Nanoparticles Inhibit the Inflammatory Response to Biodegradable Poly(lactide- co-glycolide) Implants

Biodegradable polymers have been extensively used in biomedical applications, ranging from regenerative medicine to medical devices. However, the acidic byproducts resulting from degradation can generate vigorous inflammatory reactions, often leading to clinical failure. We present an approach to prevent acid-induced inflammatory responses associated with biodegradable polymers, here poly(lactide- co-glycolide), by using oligo(lactide)-grafted magnesium hydroxide (Mg(OH)₂) nanoparticles, which neutralize the acidic environment. In particular, we demonstrated that incorporating the modified Mg(OH)₂ nanoparticles within degradable coatings on drug-eluting arterial stents efficiently attenuates the inflammatory response and in-stent intimal thickening by more than 97 and 60%, respectively, in the porcine coronary artery, compared with that of drug-eluting stent control. We also observed that decreased inflammation allows better reconstruction of mouse renal glomeruli in a kidney tissue regeneration model. Such modified Mg(OH)₂ nanoparticles may be useful to extend the applicability and improve clinical success of biodegradable devices used in various biomedical fields.

Clinical characteristics of postoperative febrile urinary tract infections after ureteroscopic lithotripsy

Purpose

Ureteroscopic lithotripsy (URS) is gaining popularity for the management of ureteral stones and even renal stones, with high efficacy and minimal invasiveness. Although this procedure is known to be safe and to have a low complication rate, febrile urinary tract infection (UTI) after URS is not rare. Therefore, we aimed to analyze the risk factors and causative pathogens of febrile UTI after URS.

Materials and Methods

Between January 2013 and June 2015, 304 patients underwent URS for ureteral or renal stones. The rate of postoperative febrile UTI and the causative pathogens were verified, and the risk factors for postoperative febrile UTI were analyzed using logistic regression analysis.

Results

Of 304 patients, postoperative febrile UTI occurred in 43 patients (14.1%). Of them, pathogens were cultured in blood or urine in 19 patients (44.2%), and definite pathogens were not identified in 24 patients (55.8%). In patients with an identified pathogen, Pseudomonas aeruginosa had the highest incidence. Multivariate analysis showed that the operation time (p<0.001) was an independent risk factor for febrile UTI after URS. The cut-off value of operation time for increased risk of febrile UTI was 70 minutes.

Conclusions

Overall, febrile UTI after URS occurred in 14.1% of patients, and the operation time was an independent predictive factor for this complication. Considering that more than 83.7% of febrile UTIs after URS were not controlled with fluoroquinolones, it may be more appropriate to use higher-level antibiotics for treatment, even in cases with unidentified pathogens.

Optimal Stem Cell Transporting Conditions to Maintain Cell Viability and Characteristics

BACKGROUND

The preservation of stem cell viability and characteristics during cell transport from the bench to patients can significantly affect the success of cell therapy. Factors such as suspending medium, time, temperature, cell density, and container type could be considered for transport conditions.

METHODS

To establish optimal conditions, human amniotic fluid stem cells' (AFSCs) viabilities were analyzed under different media {DMEM(H), DMEM/F-12, K-SFM, RPMI 1640, α-MEM, DMEM(L), PBS or saline}, temperature (4, 22 or 37 °C), cell density (1 × 10⁷ cells were suspended in 0.1, 0.5, 1.0 or 2.0 mL of medium) and container type (plastic syringe or glass bottle). After establishing the transport conditions, stem cell characteristics of AFSCs were compared to freshly prepared cells.

RESULTS

Cells transported in DMEM(H) showed relatively higher viability than other media. The optimized transport temperature was 4 °C, and available transport time was within 12 h. A lower cell density was associated with a better survival rate, and a syringe was selected as a transport container because of its clinical convenience. In compare of stem cell characteristics, the transported cells with established conditions showed similar potency as the freshly prepared cells.

CONCLUSION

Our findings can provide a foundation to optimization of conditions for stem cell transport.

Down-regulation of transient receptor potential melastatin member 7 prevents migration and invasion of renal cell carcinoma cells via inactivation of the Src and Akt pathway

Purpose

Transient receptor potential melastatin member 7 (TRPM7), an ion channel and serine/threonine protein kinase, has been linked with distinct human malignancies. However, the role of TRPM7 in renal cell carcinoma (RCC) has not been investigated. The aim of this study is to determine whether TRPM7 regulates the migration and invasion of RCC cells. Its relationship with signal transduction pathways was also studied.

Materials and Methods

The human RCC cell lines ACHN and SN12C were chosen for this study. The molecular mechanisms of TRPM7 action were studied using Western blot analysis and small interfering RNA (siRNA)-based knockdown. The effect of TRPM7 knockdown on RCC cells was measured by using Transwell invasion and wound healing migration assays.

Results

siRNA-induced silencing of TRPM7 notably decreased the migration and invasion of ACHN and SN12C RCC cells. The phosphorylation levels of Src in both cells were obviously reduced after TRPM7 silencing compared with that of the control ACHN and SN12C cells. Furthermore, the phosphorylation levels of Akt were greatly decreased in ACHN cells after siRNA-induced knockdown of TRPM7. Additionally, the treatment of cells with Src and Akt inhibitors clearly limited the migration and invasion of RCC cells.

Conclusions

Our data show that TRPM7 regulated ACHN and SN12C RCC cell invasion via the Src/Akt signaling pathway. Therefore, targeting the Src/Akt signaling pathway and/or the expression or function of TRPM7 could be a potential beneficial treatment for patients with RCC.

Publisher Correction: Renal capsular invasion is a prognostic biomarker in localized clear cell renal cell carcinoma

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