IDH2 stabilizes HIF-1α-induced metabolic reprogramming and promotes chemoresistance in urothelial cancer.

Drug resistance contributes to poor therapeutic response in urothelial carcinoma (UC). Metabolomic analysis suggested metabolic reprogramming in gemcitabine-resistant urothelial carcinoma cells, whereby increased aerobic glycolysis and metabolic stimulation of the pentose phosphate pathway (PPP) promoted pyrimidine biosynthesis to increase the production of the gemcitabine competitor deoxycytidine triphosphate (dCTP) that diminishes its therapeutic effect. Furthermore, we observed that gain-of-function of isocitrate dehydrogenase 2 (IDH2) induced reductive glutamine metabolism to stabilize Hif-1α expression and consequently stimulate aerobic glycolysis and PPP bypass in gemcitabine-resistant UC cells. Interestingly, IDH2-mediated metabolic reprogramming also caused cross resistance to CDDP, by elevating the antioxidant defense via increased NADPH and glutathione production. Downregulation or pharmacological suppression of IDH2 restored chemosensitivity. Since the expression of key metabolic enzymes, such as TIGAR, TKT, and CTPS1, were affected by IDH2-mediated metabolic reprogramming and related to poor prognosis in patients, IDH2 might become a new therapeutic target for restoring chemosensitivity in chemo-resistant urothelial carcinoma.

A microfluidic-based quantitative analysis system for the multiplexed genetic diagnosis of human viral infections using colorimetric loop-mediated isothermal amplification.

In this study, a microfluidic-based system utilizing colorimetric loop-mediated isothermal amplification (LAMP) is introduced for the quantitative analysis of nucleic acid targets. This system offers a user-friendly and cost-effective platform for the multiplexed genetic diagnosis of various infectious diseases across multiple samples. It includes time-lapse imaging equipment for capturing images of the microfluidic device during the LAMP assay and a hue-based quantitative analysis software to analyze the LAMP reaction, streamlining diagnostic procedures. An electric pipette was used to simplify the loading of samples and LAMP reagents into the device, allowing easy operation even by untrained individuals. The hue-based analysis software employs efficient image processing and post-processing techniques to calculate DNA amplification curves based on color changes in multiple reaction chambers. This software automates several tasks, such as identifying reaction chamber areas from time-lapse images, quantifying color information within each chamber, correcting baselines of DNA amplification curves, fitting experimental data to theoretical curves, and determining the threshold time for each curve. To validate the developed system, conventional off-chip LAMP assays were conducted with a 25 µL reaction mixture in 0.2 mL polymerase chain reaction (PCR) tubes using a real-time turbidimeter. The results indicated that the threshold time obtained using the colorimetric LAMP assay in the developed system is comparable to that obtained with real-time turbidity measurements in PCR tubes, demonstrating the system's capability for quantitative analysis of target nucleic acids, including those from human herpesviruses.

Predictors of surgical difficulty according to surgical proficiency in robot-assisted radical prostatectomy.

BACKGROUND: Robot-assisted radical prostatectomy (RARP) is a standard treatment for localized prostate cancer. We previously reported that a large amount of pelvic visceral fat and a small working space, as measured by three-dimensional image analysis, were significantly associated with prolonged console time in RARP, and these factors could be alternatives to the more clinically practical body mass index (BMI) and pelvic width (PW), respectively. Herein, we further investigated whether surgical proficiency affected surgical difficulty as measured by console time. METHODS: Medical records of 413 patients who underwent RARP between 2014 and 2020 at our institution were reviewed. Surgeons who had experience with over and under 100 cases were defined as "experienced" and "non-experienced," respectively. Multivariate logistic regression analyses were performed to identify factors that prolonged console time. RESULTS: The median console times for RARP by experienced and non-experienced surgeons were 87.5 and 149.0 min, respectively; a difficult case was defined as one requiring time greater than the median. Among inexperienced surgeons, higher BMI (p < 0.001, odds ratio: 1.89) and smaller PW (p = 0.001, odds ratio: 1.86) were significant factors that increased console time; the complication rate was increased in patients with these factors. However, these factors did not significantly affect the console time or complication rate among experienced surgeons. CONCLUSION: This study demonstrates that experienced surgeons may be able to overcome obesity- and small workspace-related surgical difficulties. The current analysis may provide useful information regarding unpredictable surgical risks and identify suitable cases for novices.

Usefulness of LacdiNAc-glycosylated Prostate-specific Antigen Density for Predicting Pathological Findings of Magnetic Resonance Imaging-transrectal Ultrasound Fusion Image-guided Prostate Biopsy for the Patients With Highest Prostate Imaging Reporting and Data System Category ≥3.

PURPOSE: This study aimed to evaluate the usefulness of the LDN-PSA (LacdiNAc-glycosylated-prostate specific antigen) in detecting clinically significant prostate cancer in patients suspected of having clinically significant prostate cancer on multiparametric magnetic resonance imaging. MATERIALS AND METHODS: Patients with prostate specific antigen levels ranging between 3.0 ng/mL and 20 ng/mL and suspicious lesions with PI-RADS (Prostate Imaging-Reporting and Data System) category ≥3 were included prospectively. The LDN-PSA was measured using an automated 2-step Wisteria floribunda agglutinin lectin-anti-prostate specific antigen antibody sandwich immunoassay. RESULTS: Two hundred four patients were included. Clinically significant prostate cancer was detected in 105 patients. On multivariable logistic regression analysis, prostate specific antigen density (OR 1.61, P = .010), LDN-PSAD (OR 1.04, P = .012), highest PI-RADS category (3 vs 4, 5; OR 14.5, P < .0001), and location of the lesion with highest PI-RADS category (transition zone vs peripheral zone) (OR 0.34, P = .009) were significant risk factors for detecting clinically significant prostate cancer. Among the patients with the highest PI-RADS category 3 (n=113), clinically significant prostate cancer was detected in 28 patients. On multivariable logistic regression analysis to predict the detection of clinically significant prostate cancer in patients with the highest PI-RADS category 3, age (OR 1.10, P = .026) and LDN-PSAD (OR 1.07, P < .0001) were risk factors for detecting clinically significant prostate cancer. CONCLUSIONS: LDN-PSAD would be a biomarker for detecting clinically significant prostate cancer in patients with prostate specific antigen levels ≤20 ng/mL and suspicious lesions with PI-RADS category ≥3. The use of LDN-PSAD as an adjunct to the use of prostate specific antigen levels would avoid unnecessary biopsies in patients with the highest PI-RADS category 3. Multi-institutional studies with large population are recommended.

Impact of tumor contact surface area on collecting system entry in robot-assisted partial nephrectomy: a retrospective analysis.

BACKGROUND: Collecting system entry in robot-assisted partial nephrectomy may occur even in cases showing a low N factor in the R.E.N.A.L nephrometry score. Therefore, in this study, we focused on the tumor contact surface area with the adjacent renal parenchyma and attempted to construct a novel predictive model for collecting system entry. METHODS: Among 190 patients who underwent robot-assisted partial nephrectomy at our institution from 2015 to 2021, 94 patients with a low N factor (1-2) were analyzed. Contact surface was measured with three-dimensional imaging software and defined as the C factor, classified as C1, < 10 cm [2]; C2, ≥ 10 and < 15 cm [2]; and C3: ≥ 15 cm [2]. Additionally, a modified R factor (mR) was classified as mR1, < 20 mm; mR2, ≥ 20 and < 40 mm; and mR3, ≥ 40 mm. We discussed the factors influencing collecting system entry, including the C factor, and created a novel collecting system entry predictive model. RESULTS: Collecting system entry was observed in 32 patients with a low N factor (34%). The C factor was the only independent predictive factor for collecting system entry in multivariate regression analysis (odds ratio: 4.195, 95% CI: 2.160-8.146, p < 0.0001). Models including the C factor showed better discriminative power than the models without the C factor. CONCLUSIONS: The new predictive model, including the C factor in N1-2 cases, may be beneficial, considering its indication for preoperative ureteral catheter placement in patients undergoing robot-assisted partial nephrectomy.

Risk factors for recurrence after operation in patients with pT1a renal cell carcinoma: sub-analysis of the multi-institutional national database of the Japanese Urological Association.

BACKGROUND: More patients with renal cell carcinoma are now diagnosed with the disease in its early stages. Although patients with pT1a renal cell carcinoma have a good prognosis and low recurrence rate, a few patients still experience recurrence. Herein, we evaluated the clinicopathological risk factors for postoperative recurrence of pT1aN0M0 renal cell carcinoma. METHODS: An renal cell carcinoma survey was conducted by the Japanese Urological Association to register newly diagnosed cases of renal cell carcinoma. A total of 1418 patients diagnosed with pT1aN0M0 renal cell carcinoma who underwent surgery as the primary surgical treatment were included. We analyzed the recurrence-free survival using the Kaplan-Meier method and clinicopathological factors for recurrence using Cox proportional hazards models. RESULTS: Among 1418 patients, 58 (4.1%) had recurrences after a median follow-up of 62.8 months. The median time to recurrence was 31.0 months. Metastases to the lungs and the bone were observed in 20 and 10 cases, respectively. Significant differences in sex, tumor size, Eastern Cooperative Oncology Group performance status, and dialysis history, preoperative hemoglobin levels, C-reactive protein levels and creatinine levels were observed between the recurrence and non-recurrence groups. Multivariate analysis identified male sex, high C-reactive protein level and tumor size ≥3 cm as independent risk factors. The 5-year recurrence-free survival of patients with 0, 1, 2 and 3 risk factors was 99.0, 97.2, 93.1 and 80.7%, respectively. CONCLUSIONS: Male sex, tumor diameter and a high C-reactive protein level were independent recurrence risk factors for pT1a renal cell carcinoma; special attention should be paid to patients with these risk factors during postoperative follow-up.

Preoperative factors affecting the operative outcomes of laparoscopic nephrectomy.

OBJECTIVES: Laparoscopic radical nephrectomy is the standard surgery for localized renal cell carcinoma. Both tumor and patient factors affect the difficulty of laparoscopic radical nephrectomy. Obesity is a major factor influencing technical difficulty in surgical procedures. This study examined preoperative tumor and patient factors affecting the operating time. METHODS: The data of 123 patients who underwent laparoscopic radical nephrectomy at our institution between January 2014 and December 2018 were retrospectively analyzed. The operating time was determined based on the median pneumoperitoneum time. Surgical procedures with a pneumoperitoneum time of ≥130 min were defined as having prolonged pneumoperitoneum time. Multiple logistic regression analyses were performed to identify the preoperative factors affecting the prolonged pneumoperitoneum time, and risk stratification was performed based on these factors. RESULTS: Multiple logistic regression analyses revealed that a total number of renal pedicle blood vessels ≥3 and a visceral fat volume ≥3000 cm3 were associated with prolonged pneumoperitoneum time of laparoscopic radical nephrectomy. Based on the multivariate analysis results, these factors were considered individually, and the cohort was stratified into three risk groups: low (0 point), intermediate (1 point), and high (2 points) risk groups. The pneumoperitoneum time was significantly prolonged as the number of risk factors increased. CONCLUSIONS: We developed a risk stratification model using preoperative factors to predict the prolonged pneumoperitoneum time of laparoscopic radical nephrectomy, which can help select suitable cases that are appropriate for each surgeon's skill level.

How long should urologists observe patients with prostate cancer after radical prostatectomy? Weibull analysis.

OBJECTIVES: There is no recommended observation time for patients who have undergone radical prostatectomy for prostate cancer. This study was undertaken to determine the postoperative observation time by investigating the hazard rate for prostate-specific antigen failure and other-cause death using Weibull analysis. METHODS: We included 612 patients who underwent laparoscopic radical prostatectomy for localized prostate cancer between June 2002 and December 2017. Risk classification was categorized by the D'Amico risk classification, and the patients were divided into three age groups: <60, 60-69 and ≥70 years. The hazard rates at each point were derived using Weibull analysis. The optimal observation time after laparoscopic radical prostatectomy was determined as the intersection point at which the hazard rate of other-cause death overtakes the hazard rate of prostate-specific antigen failure. RESULTS: In all groups classified by age, the hazard rate of other-cause deaths increased over time. In contrast, the hazard rate of prostate-specific antigen failure decreased gradually. The ≥70 years age group showed the highest hazard rate. The hazard rate of prostate-specific antigen failure was highest in the high-risk group. The patients aged ≥70 and 60-69 years in the low-risk group were recommended 6 years 6 months and 14 years 8 months, respectively, for observation. The remaining patients were recommended >25 years of postsurgical observation. CONCLUSIONS: The observation time after laparoscopic radical prostatectomy could be estimated by comparing the estimated hazard rates of prostate-specific antigen failure and other-cause death based on Weibull analysis. Urologists should pay attention to age and risk classifications for optimal postoperative observation.

Conditional Survival and Time of Biochemical Recurrence of Localized Prostate Cancer in Japanese Patients Undergoing Laparoscopic Radical Prostatectomies.

PURPOSE: Using conditional survival (CS) analysis, we investigated whether the duration of survival without biochemical recurrence (BCR) of prostate cancer after laparoscopic radical prostatectomies (LRP) affected the BCR rate. We also investigated the impact of well-known risk factors for BCR. METHODS: Between 2002 and 2014, 627 consecutive patients underwent LRPs at our institution. Prostate-specific antigen (PSA) concentrations above 0.2  ng/mL were defined as BCR. Conditional BCR-free survival rates were determined through Kaplan-Meier analysis. Assessment of potential BCR risk factors was performed using a Cox proportional hazard analysis. RESULTS: The 10-year BCR-free rates after LRP increased to 82.4%, 84.5%, 86.6%, 90.1%, and 94.7% in patients surviving 1, 2, 3, 5, and 7.5 years without BCR, respectively. Multivariate analyses of age, PSA concentrations, neoadjuvant therapy, and pathological findings were performed for all patients. In all patients, positive surgical margins (PSM) and Gleason Grade Groups (GG) ≥ 4 were independent risk factors for BCR (p < 0.001, hazard ratio [HR] = 2.45; and p < 0.001, HR = 2.83, respectively,). Similarly, PSM and GG ≥ 4 were significant risk factors in patients surviving 1-5 years without BCR. No clear risk factors were observed in patients surviving > 5 years without BCR after LRPs. CONCLUSIONS: The BCR-free rate increased with time after LRP. It is recommended that patients with PSM, GG ≥ 4, or with both factors are strictly monitored for 5 years postoperatively. CS analysis is particularly useful for predicting the postoperative course of patients.

Effects of psoas major muscle volume in predicting the prognosis of patients with upper urinary tract urothelial carcinoma treated with radical nephroureterectomy.

BACKGROUND: This study evaluated the impact of sarcopenia and psoas major muscle volume on the survival of patients with upper urinary tract urothelial carcinoma who had undergone radical nephroureterectomy. METHODS: We reviewed data from 110 patients treated with radical nephroureterectomy in our department between June 2007 and February 2017. Psoas major muscle volume was quantified based on computed tomography data using Synapse Vincent software. The psoas major muscle volume index was calculated as psoas major muscle volume/height squared (cm3/m2). We analysed relapse-free survival, cancer-specific survival and overall survival after radical nephroureterectomy to identify factors that predicted patient survival. RESULTS: The median psoas major muscle volume index was 121.5 cm3/m2, and the psoas major muscle volume index was <100 cm3/m2 in 34 of 110 patients (30.9%). Multivariate analysis indicated that ≥pT3-stage cancer, lymphovascular invasion and a psoas major muscle volume index of <100 cm3/m2 were independent predictors of shorter relapse-free survival, cancer-specific survival and overall survival. Using these factors, patients were stratified into three groups: low, intermediate and high risks for relapse-free survival, cancer-specific survival and overall survival. CONCLUSIONS: Low psoas major muscle volume resulting from sarcopenia, high T stage and the presence of lymphovascular invasion was associated with poor survival in patients with urinary tract urothelial carcinoma who had undergone radical nephroureterectomy, supporting the use of psoas major muscle volume as a new objective prognostic marker.