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IntroductionThe use of antibiotics may induce the changes in gut microbiota. Previous studies have shown conflicting results on whether the changed gut microbiota by antibiotics can be recovered. Our study aims to investigate whether the gut microbiota could be recovered after a single dose of oral co-amoxiclav before transrectal ultrasound-guided transperineal prostate biopsy (TPPBx) in 5 weeks’ time.MethodsFifteen patients with elevated serum prostate-specific antigen (PSA) were recruited to provide pre-antibiotic and post-antibiotic fecal samples. The V4 region of 16S rRNA was sequenced. Analysis was performed by QIIME2. Alpha- and beta-diversities were analyzed, as well as the differential enrichment by Linear discriminant analysis Effect Size (LEfSe) analysis.ResultsBoth the alpha- and beta-diversities of the pre- and post-antibiotic fecal samples were significantly different. Genera that are associated with alleviation of inflammation were enriched in the pre-antibiotic fecal samples, while the inflammation-associated genera were more enriched in the post-antibiotic fecal samples.ConclusionA single dose of oral co-amoxiclav before TPPBx could have led to a change of gut microbiota that cannot be recovered in 5 weeks' time. Microbiome studies on prostate cancer patients should be cautioned on the use of post-prostate biopsy fecal sampling. Further studies should be conducted for the impact on gut microbiome for TPPBx alone.

Prostate cancer (PCa) is a significant health concern globally, necessitating effective treatment options. Typical treatment methods for early stage, particularly localized PCa, encompass radical procedures, such as radical prostatectomy (RP) and radiotherapy (RT), and nonradical focal therapy (FT). FT is a focused approach mainly used for treating small lesions limited to a specific zone of the prostate. Its objective is to achieve cancer control when minimizing damage to benign tissue. High-intensity focused ultrasound (HIFU) is one of the most used modalities in FT for the management of PCa. The progress in HIFU technology showcases continuous advancements, offering clinicians a variety of strategies to cater to diverse patient requirements. The advancements include the development of transrectal and transurethral HIFU machines that offer enhanced treatment distances, magnetic resonance imaging (MRI) fusion capabilities, real-time monitoring, and precise ablation. These improvements contribute to increased treatment effectiveness and better outcomes for patients. This narrative review aims to summarize the use of HIFU technology and its evolution, offering diverse options to clinicians, and explores the safety, effectiveness, and quality of different HIFU strategies, such as whole-gland ablation, hemigland ablation, and focal ablation. We conclude that nonwhole-gland HIFU offers similar cancer control with better short-term functional outcomes and fewer complications compared to whole-gland ablation. Combining HIFU with transurethral resection of the prostate (TURP) improves urinary function and reduces catheterization time. Focal ablation and hemigland ablation show promise in achieving cancer control when preserving continence and potency.

This study aimed to report the outcomes of active surveillance (AS) in the management of low-risk prostate cancer (PCa). It recruited 87 men who were prospectively followed up according to the Prostate Cancer Research International Active Surveillance (PRIAS) protocol with local adaptation at SH Ho Urology Centre, Prince of Wales Hospital, Hong Kong, China. We investigated the predictors of disease progression and found that baseline prostate-specific antigen density (PSAD) and the presence of the highest Prostate Imaging-Reporting and Data System (PI-RADS) score 5 lesion on magnetic resonance imaging (MRI) are significantly correlated with disease progression. Moreover, men with PSAD >0.2 ng ml−2 or PI-RADS 4 or 5 lesions had significantly worse upgrading-free survival compared to those with PSAD ≤0.2 ng ml−2 and PI-RADS 2 or 3 lesions. The study concludes that AS is a safe and effective management strategy for selected patients to defer radical treatment and that most disease progression can be detected after the first repeated biopsy. The combination of PSAD >0.2 ng ml−2 and PI-RADS 4 or 5 lesions may serve as a useful predictor of early disease progression and provide a guide to optimize follow-up protocols for men in different risk groups.

Purpose: To investigate the effect of androgen deprivation therapy (ADT) on health-related quality of life (HRQOL) in Asian men with all stages of prostate cancer. Materials and Methods: READT (real-life evaluation of the effect of ADT in prostate cancer patients in Asia) was a multicenter, prospective observational study involving six sites across four Asian populations. We enrolled eligible prostate cancer patients, who opted for ADT alone or in combination without prior neoadjuvant or adjuvant ADT within 12 months. The EuroQoL- 5 dimensions, 5 level scale (EQ-5D-5L) utility index scores and visual analog scale (VAS) were evaluated at baseline, month 6 and month 12. Results: A total of 504 patients were recruited into READT between September 2016 and May 2020 with 52.9% diagnosed with metastatic prostate cancer. The EQ-5D-5L was evaluable in 442/504 (87.7%) of patients. Overall baseline EQ-5D-5L utility index score was 0.924 (interquartile range [IQR] 0.876–1.000). We observed a statistically significant difference in baseline EQ-5D-5L utility index score among different populations with a median EQ-5D-5L utility index score of 1 for Taiwan & Hong Kong, 0.897 for China and 0.838 for Malaysia. Similar trend was observed throughout multiple treatment timepoints. Stage IV prostate cancer were significantly associated with a lower baseline EQ-5D-5L utility index score compared to stage I–III prostate cancer, producing a median disutility value of -0.080. Participants had a high median VAS (80, IQR 70–90), indicating good overall health on average during ADT initiation. Conclusions: The study highlights the differences in health state utility index scores among various Asian prostate cancer patients receiving ADT at real-world setting. Our findings will be informative and useful in cost-effectiveness evaluation and policy decision making.

Treatment intensification with androgen deprivation therapy (ADT) and androgen receptor pathway inhibitors (ARPi) have led to improved survival in advanced prostate cancer. However, ADT is linked to significant cardiovascular toxicity, and ARPi also negatively impacts cardiovascular health. Together with a higher prevalence of baseline cardiovascular risk factors reported among prostate cancer survivors at diagnosis, there is a pressing need to prioritise and optimise cardiovascular health in this population. Firstly, While no dedicated cardiovascular toxicity risk calculators are available, other tools such as SCORE2 can be used for baseline cardiovascular risk assessment. Next, selected patients on combination therapy may benefit from de-escalation of ADT to minimise its toxicities while maintaining cancer control. These patients can be characterised by an exceptional PSA response to hormonal treatment, favourable disease characteristics and competing comorbidities that warrant a less aggressive treatment regime. In addition, emerging molecular and genomic biomarkers hold the potential to identify patients who are suited for a de-escalated treatment approach either with ADT or with ARPi. One such biomarker is AR-V7 splice variant that predicts resistance to ARPi. Lastly, optimization of modifiable cardiovascular risk factors for patients through a coherent framework (ABCDE) and exercise therapy is equally important. This article aims to comprehensively review the cardiovascular impact of hormonal manipulation in metastatic hormone-sensitive prostate cancer, propose overarching strategies to mitigate cardiovascular toxicity associated with hormonal treatment, and, most importantly, raise awareness about the detrimental cardiovascular effects inherent in our current management strategies involving hormonal agents.

Abstract Introduction Kidney cancer is a common urological malignancy worldwide with an increasing incidence in recent years. Among all subtypes, renal cell carcinoma (RCC) represents the most predominant malignancy in kidney. Clinicians faced a major challenge to select the most effective and suitable treatment regime for patients from a wide range of modalities, despite improved understanding and diagnosis of RCC. Objective Recently, organoid culture gained more interest as the 3D model is shown to be highly patient specific which is hypothetically beneficial to the investigation of precision medicine. Nonetheless, the development and application of organotypic culture in RCC is still immature, therefore, the primary objective of this study was to establish an organoid model for RCC. Materials and Methods Patients diagnosed with renal tumor and underwent surgical intervention were recruited. RCC specimen was collected and derived into organoids. Derived organoids were validated by histological examminations, sequencing and xenograft. Drug response of organoids were compared with resistance cell line and patients' clinical outcomes. Results Our results demonstrated that organoids could be successfully derived from renal tumor and they exhibited high concordance in terms of immunoexpressional patterns. Sequencing results also depicted concordant mutations of driver genes in both organoids and parental tumor tissues. Critical and novel growth factors were discovered during the establishment of organoid model. Besides, organoids derived from renal tumor exhibited tumorigenic properties in vivo. In addition, organoids recapitulated patient's in vivo drug resistance and served as a platform to predict responsiveness of other therapeutic agents. Conclusion Our RCC organoid model recaptiluated histological and genetic features observed in primary tumors. It also served as a potential platform in drug screening for RCC patients, though future studies are necessary before translating the outcomes into clinical practices.

Background: An incidental COVID-19 infection is often found in patients admitted for non-COVID-19-related conditions. This study aims to investigate the incidence of COVID-19 infections across surgical specialties including urology, general surgery, and orthopaedic surgery. Methods: This is a retrospective cohort study based on a territory-wide electronic database in Hong Kong. All emergency in-hospital admissions under the urology, general surgery, and orthopaedic surgery divisions in the public healthcare system in Hong Kong from January to September 2022 were included. All patients were routinely screened for SARS-CoV-2, based on admission protocols during the investigation period. Baseline characteristics were retrieved, with 1:1:1 propensity score matching being performed. Incidental COVID-19 rates were then compared across specialties. Results: A total of 126,034 patients were included. After propensity score matching, the baseline characteristics were well balanced, and 8535 patients in each group were analysed. Urology admission was noted to have a statistically significant higher incidence of incidental COVID-19 at 9.3%, compared to general surgery (5.4%) or orthopaedic surgery (5.6%). Amongst urology patients with incidental COVID-19 infection, 35.8% were admitted for retention of urine, 27.9% for haematuria, and 8.6% for a urinary tract infection. Conclusions: This large-scale cohort study demonstrated that incidental COVID-19 rates differ between surgical specialties, with urology having the highest proportion of incidental COVID-19 infection.

PurposeIn the era of concurrent combination therapy in metastatic hormone sensitive prostate cancer, the impact of the testosterone level before initiating androgen deprivation therapy on treatment outcome is still uncertain. We aimed to investigate its effect on time-to-castration-resistance in a metastatic hormone sensitive prostate cancer cohort.MethodsThis is a multi-center retrospective study of 5 databases from China, Japan, Austria and Spain including 258 metastatic hormone sensitive prostate cancer patients with androgen deprivation therapy initiated between 2002 and 2021. Baseline testosterone was divided into high and low groups using 12 nmol/L as cutoff level. Primary outcome was time-to-castration-resistance. Secondary outcomes were survival functions. Kaplan-Meier method was employed to evaluate the correlation between baseline testosterone and time-to-castration-resistance. Subgroup analysis was performed to elucidate the effect of upfront combination-therapy and metastatic volume.ResultsMedian age was 72 years. Median follow-up time was 31 months. Median pre-treatment prostate-specific-antigen level was 161 ng/mL. Majority of case were graded as International-Society-of-Urological-Pathology grade 5 (63.6%). 57.8% patients had high volume disease and 69.0% received upfront combination treatment. 44.6% of the cohort developed castration-resistance. The low testosterone group demonstrated shorter mean-time-to-castration-resistance (19.0 vs 22.4 months, p=0.031). The variance was more significant in patients without combination therapy (13.2 vs 26.3 months, p=0.015). Cancer-specific and overall survival were inferior in the low baseline testosterone level group without receiving combination therapy (p=0.001).ConclusionsLower pre-treatment testosterone level is correlated to shorter time-to-castration resistance and worse survival in metastatic prostate cancer patients without upfront combination therapy. Those with low baseline testosterone should be encouraged to adopt combination therapy to delay progression.

Objective. The study aimed at investigating the outcome of prostate HIFU focal therapy using the MRI-US fusion platform for treatment localization and delivery. Methods. It is a prospectively designed case series of HIFU focal therapy for localized prostate cancer. The inclusion criteria include clinical tumor stage ≤T2, visible index lesion on multiparametric MRI less than 20 mm in diameter, absence of Gleason 5 pattern on prostate biopsy, and PSA ≤ 20 ng/ml. HIFU focal therapy was performed in the conventional manner in the beginning 50% of the series, whereas the subsequent cases were performed with MRI-US fusion platform. The primary outcome was treatment failure rate which is defined by the need of salvage therapy. Secondary outcomes included tumor recurrence in follow-up biopsy, PSA change, perioperative complications, and postoperative functional outcomes. Results. Twenty patients underwent HIFU focal ablation. HIFU on an MRI-US fusion platform had a trend of a longer total operative time than the conventional counterpart (124.2 min vs. 107.1 min, p=0.066). There was no difference in the mean ablation volume to lesion volume ratio between the two. The mean PSA percentage change from baseline to 6-month is more significant in the conventional group (63.3% vs. 44.6%, p=0.035). No suspicious lesion was seen at 6-month mpMRI in all 20 patients. Two patients, one from each group, eventually underwent radical treatment because of the presence of clinically significant prostate cancer in the form of out-of-field recurrences during follow-up biopsy. No significant difference was observed before and after HIFU concerning uroflowmetry, SF-12 score, and EPIC-26 score. It was observed that energy used per volume was positively correlated with PSA density of the patient (r = 0.6364, p=0.014). Conclusion. In conclusion, HIFU with conventional or MRI-US fusion platform provided similar oncological and functional outcomes.

Objective: To demonstrate the execution of augmentation gastrocystoplasty in a total robotic approach. Materials: A 27-year-old lady presented with a fibrotic and contracted urinary bladder secondary to ketamine abuse. Her impaired renal function rendered her unfit for ileo-cystoplasty. Robotic augmentation gastrocystoplasty was performed, beginning with the stomach part in a head-up position. 10 cm wedge of stomach was used as the patch to augment the bladder, preserving the right gastro-epiploic vessel as its blood supply. The bladder part was completed with redocking of the robot and putting the patient in a slight Trendelenburg position. Upon completion of the procedure, the patient had a urethral Foley catheter and a pelvic drain in place. The whole procedure was performed by the urology team. Results: Operation time was 275 min. Blood loss was 100 ml. Nasogastric tube was taken off on post-op day 2. The patient was discharged on post-op day 6. Foley was taken off on post-op day 14. Recovery course was smooth without complication. At 1 year, functional bladder capacity was 330 ml. The patient's renal function remained static. Conclusions: Total robotic augmentation gastrocystoplasty is a safe alternative to the conventional open approach. Long term outcome assessment is necessary to determine if this minimal invasive approach can be recommended as one of the standard options in this setting.

Emerging studies demonstrate that PIWI-interacting RNAs (piRNAs) are associated with various human cancers. This study aimed to evaluate the urinary extracellular vesicles (EVs) piRNAs as non-invasive biomarkers for prostate cancer (PCa) diagnosis. RNA was extracted from urinary EVs from five PCa patients and five healthy controls (HC), and the piRNAs were analyzed by small RNA sequencing. Dysregulated piRNAs were identified and then validated in another 30 PCa patients and 10 HC by reverse-transcription polymerase chain reaction (RT-qPCR). The expressions of novel_pir349843, novel_pir382289, novel_pir158533, and hsa_piR_002468 in urinary EVs were significantly increased in the PCa group compared with the HC group. The area under the curve (AUC) of novel_pir158533, novel_pir349843, novel_pir382289, hsa_piR_002468, and the combination of the four piRNA in PCa diagnosis was 0.723, 0.757, 0.777, 0.783, and 0.853, respectively. After the RNAhybrid program analysis, all four piRNAs had multiple potential binding sites with key mRNAs in PTEN/PI3K/Akt, Wnt/beta-catenin, or androgen receptor pathway, which are critical in PCa development and progression. In conclusion, our findings indicate that specific piRNAs in urinary EVs may serve as non-invasive diagnostic biomarkers for PCa.

The development of castration resistance is an inevitable pathway for the vast majority of patients with advanced prostate cancer. Recently, there have been significant breakthroughs in the understanding and management options of castration-resistant prostate cancer. Three novel hormonal agents showed survival benefits in non-metastatic patients. As for metastatic disease, there was an even wider range of management options being investigated. This review summarized advances in the management of castration-resistant prostate cancer (CRPC) including emerging data on novel imaging techniques and treatment strategies.

Urinary bladder cancer is a common urological cancer. Although flexible cystoscopy is widely employed in bladder cancer detection, it is expensive, invasive, and uncomfortable to the patients. Recently, urinary cell-free DNA (ucfDNA) isolated from urine supernatant has been shown to have great potential in bladder cancer detection and surveillance. Molecular features, such as integrity and concentration of ucfDNA, have been shown to be useful for differentiating bladder cancer patients from healthy controls. Besides, bladder cancer also exhibits unique genetic features that can be identified from sequencing and expression of ucfDNA. Apart from bladder cancer detection, ucfDNA is also useful for molecular classification. For example, ucfDNA exhibits significant differences, both molecularly and genetically, in non-muscle-invasive and muscle-invasive bladder cancers. There is no doubt that ucfDNA is a very promising tool for future applications in the field of bladder cancer.

This study plans to evaluate the updated global trends of prostate cancer for individual and countries by different age groups (= 50 years vs. < 50 years). We retrieved data from national and global cancer registries for trend analysis. Incidence trend kept rising, especially among younger population with aged 50 or below, while mortality trend kept dropping. Background: We aimed to examine the global disease burden and trends of prostate cancer incidence and mortality by age, and their associations with gross domestic product (GDP), human development index (HDI), smoking, and alcohol drinking. Materials and Methods: We retrieved the Global Cancer Observatory (GLOBOCAN) database for the incidence and mortality of prostate cancer in 2020; the World Bank for GDP per capita; the United Nations for HDI; the WHO Global Health Obser vator y for prevalence of smoking and alcohol drinking; the Cancer Incidence in 5 Continents (CI5), WHO mortality database, for trend analysis. We presented the prostate cancer incidence and mortality using age-standardized rates. We examined their associations with GDP, HDI, smoking, and alcohol drinking by Spearman's correlations and multivariable regression. We estimated the 10-year trend of incidence and mortality by joinpoint regression analysis with average annual percent change with 95% confidence intervals in different age groups. Results: A wide variation in the burden of prostate cancer with the highest mortality found in low-income countries while the highest incidence was observed in high-income countries. We found moderate to high positive correlations for GDP, HDI, and alcohol drinking with prostate cancer incidence, whilst a low negative correlation was observed for smoking. Globally, there was an increasing incidence but decreasing mortality of prostate cancer, and such trends were particularly prominent in Europe. Notably, the incidence increase was also found in the younger population aged < 50 years. Conclusions: There was a global variation in the burden of prostate cancer associated with GDP, HDI, smoking, and alcohol drinking. [ABSTRACT FROM AUTHOR]

Purpose: We compare Prostate Health Index, Prostate Health Index density, and PSA density in predicting clinically significant prostate cancer in MRI-guided prostate biopsy. Materials and Methods: This is a multicenter evaluation of prospectively maintained prostate biopsy databases at 10 urology centers. Men with Prostate Health Index and MRI-guided targeted and systematic prostate biopsy performed and without prior prostate cancer diagnosis were included. The additional value of PSA density, Prostate Health Index, and Prostate Health Index density to MRI PI-RADS (Prostate Imaging Reporting & Data System) score was evaluated with multivariable analyses, area under the curve, and decision curve analyses. The proportion of unnecessary biopsies that can be avoided are estimated for clinically significant prostate cancer (International Society of Urological Pathology group >2 prostate cancer). Results: A total of 1,215 men were analyzed. Prostate cancer and clinically significant prostate cancer were diagnosed in 51% (617/1,215) and 35% (422/1,215) of men, respectively. Clinically significant prostate cancer was diagnosed in 4.4% (3/68), 15% (72/470), 39% (176/446), and 74% (171/231) of highest PI-RADS score of 2, 3, 4, and 5 lesions, respectively. In multivariable analyses, independent predictors for clinically significant prostate cancer detection included Prostate Health Index (OR 1.04), prostate volume (OR 0.97), and PI-RADS score 4 (OR 2.81) and 5 (OR 8.34). Area under the curve for clinically significant prostate cancer of PI-RADS D Prostate Health Index density (0.85) was superior to PI-RADSDPSA density (0.81), Prostate Health Index density (0.81), Prostate Health Index (0.78), PI-RADS (0.76), PSA density (0.72), and PSA (0.60) in the whole cohort, and the superiority of Prostate Health Index density was also observed in PI-RADS 3 lesions. Decision curve analysis showed Prostate Health Index density achieving the best net clinical benefit in PI-RADS 3 or 4 cases. Among PI-RADS 3 lesions, using cutoffs of PSA density 0.15, Prostate Health Index 38.0, and Prostate Health Index density 0.83 could reduce 58%, 67%, and 72% of unnecessary biopsies, respectively. Conclusions: Prostate Health Index density outperformed Prostate Health Index or PSA density in clinically significant prostate cancer detection in men with multiparametric MRI performed, and further reduced unnecessary biopsies in PI-RADS 3 lesions. [ABSTRACT FROM AUTHOR]

Introduction: We evaluated the factors associated with secondary hemorrhage after bipolar transurethral resection of prostate (TURP) and vaporization of prostate. Materials and Methods: The perioperative data of patients undergoing endoscopic surgery for benign prostatic hyperplasia (BPH) were prospectively collected. Procedures involved included bipolar TURP, bipolar vaporization of prostate, and hybrid bipolar TURP/vaporization of prostate. Secondary hemorrhage was defined as bleeding between 48 h and 30 days postsurgery requiring hospital attendance with or without admission. Risk factors for secondary hemorrhage were analyzed. Results: From 2010 to 2013, 316 patients underwent bipolar surgery for BPH. Bipolar TURP accounted for 48.1% of the procedures, bipolar vaporization accounted for 20.3% of the procedures, and the rest were hybrid TURP/vaporization of prostate. Among this cohort of patients, fifty patients had secondary hemorrhage with hospital attendance. Consumption of platelet aggregation inhibitors (PAIs) was found to be associated with secondary hemorrhage (P < 0.0005). Age, prostate volume, operation type, the use of 5-alpha reductase inhibitors, and being with a urethral catheter before operation were not found to be statistically significant risk factors for secondary hemorrhage. Conclusions: Secondary hemorrhage after bipolar surgery for BPH is a common event. Consumption of PAI is a risk factor for such complication. [ABSTRACT FROM AUTHOR]

Purpose: We investigated the extended use of Prostate Health Index (PHI) and percentage of [-2]pro-prostate-specific antigen (%p2PSA) in Chinese men with prostate-specific antigen (PSA) 10-20 ng/mL and normal digital rectal examination (DRE). Materials and Methods: All consecutive Chinese men with PSA 10-20 ng/mL and normal DRE who agreed for transrectal ultrasound (TRUS)-guided 10-core prostate biopsy were recruited. Blood samples were taken immediately before TRUS-guided prostate biopsy. The performances of total PSA (tPSA), %free-to-total PSA (%fPSA), %p2PSA, and PHI were compared using logistic regression, receiver operating characteristic, and decision curve analyses (DCA). Results: From 2008 to 2015, 312 consecutive Chinese men were included. Among them, 53 out of 312 (17.0%) men were diagnosed to have prostate cancer on biopsy. The proportions of men with positive biopsies were 6.7% in PHI<35, 22.8% in PHI 35-55, and 54.5% in PHI>55 (chi-square test, p<0.001). The area under curves (AUC) of the base model including age, tPSA and status of initial/repeated biopsy was 0.64. Adding %p2PSA and PHI to the base model improved the AUC to 0.79 (p<0.001) and 0.78 (p<0.001), respectively, and provided net clinical benefit in DCA. The positive biopsy rates of Gleason 7 or above prostate cancers were 2.2% for PHI<35, 7.9% for PHI 35-55, and 36.4% for PHI>55 (chi-square test, p<0.001). By utilizing the PHI cutoff of 35 to men with PSA 10-20 ng/mL and normal DRE, 57.1% (178 of 312) biopsies could be avoided. Conclusions: Both PHI and %p2PSA performed well in predicting prostate cancer and high grade prostate cancer. The use of PHI and %p2PSA should be extended to Chinese men with PSA 10-20 ng/mL and normal DRE. [ABSTRACT FROM AUTHOR]

Objectives: To investigate the role of urine spermine and spermine risk score in predicting prostate cancer (PCa) diagnoses in combination with multiparametric magnetic resonance imaging (mpMRI). Methods: Three hundred forty seven consecutive men with elevated prostate-specific antigen (PSA) with mpMRI examination were prospectively enrolled in this study. In 265 patients with PSA levels between 4 and20 ng/ml, pre-biopsy urine samples were analyzed for spermine levels with ultra-high performance liquid chromatography (UPLC-MS/MS). Transperineal image-guided prostate biopsies with 16-18 cores were performed. Logistic regressions were used to form different models for the prediction of the PCa, and the performances were compared using the area under the curve (AUC). Results: The median serum PSA level and prostate volume were 7.4 ng/mL and 33.9 mL, respectively. PCa and high-grade PCa (ISUP group ≥2, HGPCa) were diagnosed in 66.0% (175/265) and 132/265 (49.8%) cases, respectively. The urine spermine levels were significantly lower in men with PCa (0.87 vs. 2.20, P

Although the role of METTL3 has been extensively studied in many cancers, its role in isoform switching in prostate cancer (PCa) has been poorly explored. To investigate its role, we applied standard RNA-sequencing and long-read direct RNA-sequencing from Oxford Nanopore to examine how METTL3 affects alternative splicing (AS) in two PCa cell lines. By dissecting genome-wide METTL3-regulated AS events, we noted that two PCa cell lines (representing two different PCa subtypes, androgen-sensitive or resistant) behave differently in exon skipping and intron retention events following METTL3 depletion, suggesting AS heterogeneity in PCa. Moreover, we revealed that METTL3-regulated AS is dependent on N6-methyladenosine (m6A) and distinct splicing factors. Analysis of the AS landscape also revealed cell type specific AS signatures for some genes (e.g., MKNK2) involved in key functions in PCa tumorigenesis. Finally, we also validated the clinical relevance of MKNK2 AS events in PCa patients and pointed to the possible regulatory mechanism related to m6A in the exon14a/b region and SRSF1. Overall, we characterize the role of METTL3 in regulating PCa-associated AS programs, expand the role of METTL3 in tumorigenesis, and suggest that MKNK2 AS events may serve as a new potential prognostic biomarker.

Abstract Background Accumulating evidence supports that prostate cancer stem-like cells (PCSCs) play significant roles in therapy resistance and metastasis of prostate cancer. Many studies also show that nitric oxide (NO) synthesized by NO synthases can function to promote tumor progression. However, the exact roles of NOSs and NO signaling in the growth regulation of PCSCs and castration-resistant prostate cancer (CRPC) are still not fully understood. Methods The regulatory functions of NOS-NO signaling were evaluated in prostate cancer cells, especially in PCSCs enriched by 3D spheroid culture and CD133/CD44 cell sorting. The molecular mechanisms of NOS-NO signaling in PCSCs growth regulation and tumor metastasis were investigated in PCSCs and mice orthotopic prostate tumor model. Results Endothelial NOS (eNOS) exhibited a significant upregulation in high-grade prostate cancer and metastatic CRPC. Xenograft models of CRPC exhibited notable increased eNOS expression and higher intracellular NO levels. PCSCs isolated from various models displayed significant enhanced eNOS-NO signaling. Functional analyses demonstrated that increased eNOS expression could promote in vivo tumorigenicity and metastatic potential of prostate cancer cells. Characterization of eNOS-NO involved downstream pathway which confirmed that enhanced eNOS signaling could promote the growth of PCSCs and antiandrogen-resistant prostate cancer cells via an activated downstream NO-sGC-cGMP-PKG effector signaling pathway. Interestingly, eNOS expression could be co-targeted by nuclear receptor ERRα and transcription factor ERG in prostate cancer cells and PCSCs. Conclusions Enhanced eNOS-NO signaling could function to promote the growth of PCSCs and also the development of metastatic CRPC. Besides eNOS-NO as potential targets, targeting its upstream regulators (ERRα and ERG) of eNOS-NO signaling could also be the therapeutic strategy for the management of advanced prostate cancer, particularly the aggressive cancer carrying with the TMPRSS2:ERG fusion gene.

Prostate cancer is the most inheritable cancer with approximately 42% of disease risk attributed to inherited factors by studies of twins, indicating the importance of additional genetic screening to identify predisposition variants. However, only DNA damage repair (DDR) genes have been investigated thoroughly in prostate cancer. To determine the comprehensive germline mutation landscape in Chinese prostate cancer patients, we performed whole exome sequencing in 100 Han Chinese patients with prostate cancer in Hong Kong and identified deleterious germline mutations. A total of 36 deleterious germline variants in 25 genes were identified in 29% patients. Variants were found in eight pathways, including DNA methylation, DDR, and tyrosine-protein kinase. These findings were validated in an independent Chinese cohort of 167 patients with prostate cancer in Shanghai. Seven common deleterious-variant-containing genes were found in discovery cohort (7/25, 28%) and validation cohort (7/28, 25%) with three genes not described before (LDLR, MYH7 and SUGCT) and four genes previously reported (FANCI, ITGA6, PABPC1 and RAD54B). When comparing with that of a cohort of East Asian healthy individuals, 12 non-DDR novel potential predisposition genes (ADGRG1, CHD4, DNMT3A, ERBB3, GRHL1, HMBS, LDLR, MYH7, MYO6, NT5C2, NUP98 and SUGCT) were identified using the discovery and validation cohorts, which have not been previously reported in prostate cancer patients in all ethnic groups. Taken together, this study reveals a comprehensive germline mutation landscape in Chinese prostate cancer patients and discovers 12 novel non-DDR predisposition genes to lay the groundwork for the optimization of genetic screening.

BackgroundBladder cancer (CaB) has a high recurrence rate despite surgery. As bladder is constantly filled with urine, it is worthwhile to investigate whether it could have any detrimental effects on bladder cancer cells.MethodsWe investigated the cytotoxicity of urine samples from CaB patients and normal controls on four CaB cell lines and tested the percentage of cell death, proliferation, adhesion, invasion and colonies formation ability. In order to identify the potential components involving in urine cytotoxicity, we evaluated some basic physiochemical parameters of urines, such as pH, osmolarity, creatinine (Cr), sodium (Na), potassium (K), chloride (Cl), calcium (Ca) and phosphate (PO4). We further compared the pH values of urine samples between CaB who developed recurrence versus those who did not. A more in-depth analysis on inflammatory markers was performed for two representative urine samples which demonstrated opposite cytoxic effects.Results23 CaB patients and 20 normal controls were recruited into this study. According to in vitro experiments, both CaB and non-CaB urines had comparable effect on cell toxicity, proliferation, adhesion, invasion and colonies formation ability in four cell lines, HTB9, RT4, T24 and UMUC3, while RT4 was the most sensitive to urine toxicity. After evaluating the relationship between basic physiochemical parameters and cytotoxicity, we found out that there were strong negative correlations between pH value and 24 hours death rate for the 4 CaB cell lines (HTB9 r = -0.6651, pConclusionsOur study confirmed that there was not statistically significant difference in cytotoxicity between CaB and non-CaB urines. However, we identified some parameters that could have an impact on cytotoxicity towards CaB cells. Modifying certain urine characteristics peri-operatively may induce cytotoxicity, avoid tumour re-implantation, and reduce the chance of cancer recurrence.