Current Trends and Challenges of Microbiome Research in Bladder Cancer.

PURPOSE OF THE REVIEW: Microbiome research has provided valuable insights into the associations between microbial communities and bladder cancer. However, this field faces significant challenges that hinder the interpretation, generalization, and translation of findings into clinical practice. This review aims to elucidate these challenges and highlight the importance of addressing them for the advancement of microbiome research in bladder cancer. RECENT FINDINGS: Recent findings underscore the complexities involved in microbiome research, particularly in the context of bladder cancer. Challenges include low microbial biomass in urine samples, potential contamination issues during collection and processing, variability in sequencing methods and primer selection, and the difficulty of establishing causality between microbiota and bladder cancer. Studies have shown the impact of sample storage conditions and DNA isolation kits on microbiome analysis, emphasizing the need for standardization. Additionally, variations in urine collection methods can introduce contamination and affect results. The choice of 16S rRNA gene amplicon sequencing or shotgun metagenomic sequencing introduces technical challenges, including primer selection and sequencing read length. Establishing causality between the microbiota and bladder cancer requires experimental methods like fecal microbiota transplantation and human microbiota-associated murine models, which face their own set of challenges. Translating microbiome research into therapeutic applications is hindered by methodological variability, incomplete understanding of bioactive molecules, imperfect animal models, and the inherent heterogeneity of microbiome communities among individuals. Microbiome research in bladder cancer presents significant challenges stemming from technical and conceptual complexities. Addressing these challenges through standardization, improved experimental models, and advanced analytical approaches is essential for advancing our understanding of the microbiome's role in bladder cancer and its potential clinical applications. Achieving this goal can lead to improved patient outcomes and novel therapeutic strategies in the future.

Dexamethasone eluting polydopaminated polycaprolactone-poly (lactic-co-glycolic) acid for treatment of tracheal stenosis.

Tracheal stenosis is commonly caused by injury, resulting in inflammation and fibrosis. Inhibiting inflammation and promoting epithelization can reduce recurrence after initial successful treatment of tracheal stenosis. Steroids play an important role in tracheal stenosis management. This study in vitro evaluated effectiveness of a polydopaminated polycaprolactone stent coated with dexamethasone-eluting poly(lactic-co-glycolic) acid microparticles (µPLGA) for tracheal stenosis management. Polydopamination was characterized by Raman spectroscopy and promoted epithelialization while dexamethasone delivery reduced macrophage activity, assessed by individual cell area measurements and immunofluorescent staining for inducible nitric oxide synthase (iNOS). Dexamethasone release was quantified by high-performance liquid chromatography over 30 days. Activation-related increase in cell area and iNOS production by RAW 264.7 were both reduced significantly (p < .05) through dexamethasone release. Epithelial cell spreading was higher on polydopaminated polycaprolactone (PCL) than PCL-alone (p < .05). Force required for stent migration was measured by pullout tests of PCL-µPLGA stents from cadaveric rabbit and porcine tracheas (0.425 ± 0.068 N and 1.082 ± 0.064 N, respectively) were above forces estimated to occur during forced respiration. Biomechanical support provided by stents to prevent airway collapse was assessed by comparing compressive circumferential stiffness, and stiffness of the stent was about 1/10th of the rabbit trachea (0.156 ± 0.023 N/mm vs. 1.420 ± 0.194 N/mm, respectively). A dexamethasone-loaded PCL-µPLGA stent platform can deliver dexamethasone and exhibits sufficient mechanical properties to anchor within the trachea and polydopamination of PCL is conducive to epithelial layer formation. Therefore, a polydopaminated PCL-µPLGA stent is a promising candidate for in vivo evaluation for treatment of tracheal restenosis.

Recurrent urinary tract infection genetic risk: a systematic review and gene network analysis.

INTRODUCTION AND HYPOTHESIS: The development of recurrent urinary tract infections (rUTIs) is not completely understood. This review is aimed at investigating the connection between genetics and rUTIs and summarizing the results of studies that have documented variations in gene expression among individuals with rUTIs compared with healthy individuals. METHODS: A systematic search was conducted in Cochrane, Ovid, and PubMed, limiting the results to articles published between 1 January 2000, and 5 July 2022. Only studies comparing the difference in gene expression between individuals with rUTI and healthy individuals utilizing molecular techniques to measure gene expression in blood or urine samples were included in this systematic review. Gene network and pathways analyses were performed using Cytoscape software, with input data obtained from our systematic review of differentially expressed genes in rUTIs. RESULTS: Six studies met our criteria for inclusion. The selected studies used molecular biology methods to quantify gene expression data from blood specimens. The analysis revealed that gene expressions of CXCR1 and TLR4 decreased, whereas CXCR2, TRIF, and SIGIRR increased in patients with rUTI compared with healthy controls. The analysis demonstrated that the most significant pathways were associated with TLR receptor signaling and tolerance, I-kappa B kinase/NF-kappa B signaling, and MyD88-independent TLR signaling. CONCLUSIONS: This systematic review uncovered gene expression variations in several candidate genes and identified a number of underlying biological pathways associated with rUTIs. These findings could shift the treatment and prevention strategies for rUTIs.

Genomic Risk Factors for Urethral Stricture: A Systematic Review and Gene Network Analysis.

OBJECTIVE: To identify genes that may play a role in urethral stricture and summarize the results of studies that have documented variations in gene expression among individuals with urethral stricture compared to healthy individuals. METHODS: A systematic search was conducted in Cochrane, Ovid, Web of Science, and PubMed, limiting the results to articles published between January 1, 2000 and January 30, 2023. Only studies comparing the difference in gene expression between individuals with urethral stricture and healthy individuals utilizing molecular techniques to measure gene expression in blood, urine, or tissue samples were included in this systematic review. Gene network and pathway analyses were performed using Cytoscape software, with input data obtained from our systematic review of differentially expressed genes in urethral stricture. RESULTS: Four studies met our criteria for inclusion. The studies used molecular biology methods to quantify gene expression data from specimens. The analysis revealed gene expressions of CXCR3 and NOS2 were downregulated in urethral tissue samples, while TGFB1, UPK3A, and CTGF were upregulated in plasma, urine and urethral tissue samples, respectively, in patients with urethral stricture compared to healthy controls. The analysis demonstrated that the most significant pathways were associated with phosphoinositide 3-kinase (PI3 kinase) and transforming growth factor beta 1/suppressor of mothers against decapentaplegic (TGF-ß1/SMAD) signaling pathways. CONCLUSION: This systematic review identified gene expression variations in several candidate genes and identified underlying biological pathways associated with urethral stricture. These findings could inform further research and potentially shift treatment and prevention strategies for urethral stricture.

Female sexual function evaluation and intraoperative vaginal reconstruction in bladder cancer.

RC significantly negatively impacts sexual function (SF) in both men and women. While significant research resources have been allocated to examine the deleterious effects of post prostatectomy erectile dysfunction, little attention has been directed towards female sexual function and organ preservation post cystectomy. These academic shortcomings often result in poor provider awareness and inadequate preoperative assessment. As such, it is crucial for all providers involved in female RC care to understand the necessary and available tools for preoperative evaluation, in addition to the anatomic and reconstructive techniques. This review aims to summarize the current preoperative evaluation and available tools of SF assessment and describe in detail the varying operative techniques in the preservation or restoration of SF in women after RC. The review explores the intricacies of preoperative evaluation tools, and intraoperative techniques for organ- and nerve-sparing during radical cystectomy in females. Particular emphasis on vaginal reconstruction after partial or complete resection is provided, including split-thickness skin (STF) graft vaginoplasy, pedicled flaps, myocutaneous flaps and use of bowel segments. In conclusion, this narrative review highlights the importance of understanding anatomic considerations and nerve-sparing strategies in promoting postoperative SF and quality of life. Furthermore, the review describes the advantages and limitations of each organ- and nerve-sparing technique and their impact on sexual function and overall well-being.

Targeting bladder cancer: A sex sensitive perspective in mutations and outcomes.

The incidence of bladder cancer (BC) is more common in males, however, the clinical outcome for females tends to be more unfavorable, as demonstrated by a 21% increase in mortality compared to males within two years of diagnosis. While it was previously believed that the differences in outcome were solely the result of differences in sex chromosomes and hormones, it is now acknowledged that a more intricate interplay of factors is at play. By acquiring a more comprehensive understanding of these sex-specific effects, future efforts in precision medicine can be customized to an individual's biological sex. This narrative review aims to summarize our knowledge of the molecular classification of sex differences in BC by compiling the existing evidence on genetic disparities between males and females and evaluating these disparities in both noninvasive bladder cancer (NMIBC) and muscle invasive bladder cancer (MIBC). Our findings emphasize the significance of considering sex as a factor in future clinical trials and registry studies due to established differences in immune composition, molecular profiling, and genetic mutations between males and females. Further investigation into the molecular processes involved in the evasion or resistance of immune-based therapies, such as Bacillus Calmette-Guérin and other immunotherapies, is essential to identify markers of response or resistance that vary between male and female patients. This will aid in optimizing treatment and promoting equitable outcomes, particularly in NMIBC cases.

Cost-effectiveness analysis of arterial catheter insertion on robotic-assisted laparoscopic prostatectomy.

INTRODUCTION: To evaluate the utility, outcomes, and cost of arterial line placement in a single institution cohort of patients undergoing robotic-assisted laparoscopic prostatectomy (RALP). MATERIALS AND METHODS: A retrospective chart review was performed at a large tertiary care center from July 2018 through January 2021. Hospital costs and cost-effective analysis was performed on patients with and without arterial line placement. Means with standard deviations were used to report continuous variables, while numbers and percentages were utilized to describe categorical variables. T-tests and Chi-square tests compared categorical and continuous variables across study cohorts, respectively. Multivariable analyses were used to examine the association between A-line placement and outcomes as mentioned above adjusting for the effect of other co-variables. RESULTS: Among the 296 included patients, 138 (46.6%) had arterial lines. No preoperative patient characteristic predicted arterial line placement. Rates of complications and re-admissions were not statistically significant between the two groups. Arterial line use was associated with higher volumes of intraoperative fluid administration, as well as a longer hospital length of stay. Total cost and operative time did not significantly differ between cohorts, but arterial line placement increased variability of these factors. CONCLUSION: The use of arterial lines in patients undergoing RALP is not necessarily guideline-driven and does not decrease the rate of perioperative complications. However, it is associated with longer length of stay and increases variability in charge. These data show that the surgical team and anesthesia team should critically evaluate the need for arterial line placement in patients undergoing RALP.

Global Meta-analysis of Urine Microbiome: Colonization of Polycyclic Aromatic Hydrocarbon-degrading Bacteria Among Bladder Cancer Patients.

BACKGROUND: The application of next-generation sequencing techniques has enabled characterization of urinary tract microbiome. Although many studies have demonstrated associations between the human microbiome and bladder cancer (BC), these have not always reported consistent results, thereby necessitating cross-study comparisons. Thus, the fundamental questions remain how we can utilize this knowledge. OBJECTIVE: The aim of our study was to examine the disease-associated changes in urine microbiome communities globally utilizing a machine learning algorithm. DESIGN, SETTING, AND PARTICIPANTS: Raw FASTQ files were downloaded for the three published studies in urinary microbiome in BC patients, in addition to our own prospectively collected cohort. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Demultiplexing and classification were performed using the QIIME 2020.8 platform. De novo operational taxonomic units were clustered using the uCLUST algorithm and defined by 97% sequence similarity and classified at the phylum level against the Silva RNA sequence database. The metadata available from the three studies included were used to evaluate the differential abundance between BC patients and controls via a random-effect meta-analysis using the metagen R function. A machine learning analysis was performed using the SIAMCAT R package. RESULTS AND LIMITATIONS: Our study includes 129 BC urine and 60 healthy control samples across four different countries. We identified a total of 97/548 genera to be differentially abundant in the BC urine microbiome compared with that of healthy patients. Overall, while the differences in diversity metrics were clustered around the country of origin (Kruskal-Wallis, p < 0.001), collection methodology was a driver of microbiome composition. When assessing dataset from China, Hungary, and Croatia, data demonstrated no discrimination capacity to distinguish between BC patients and healthy adults (area under the curve [AUC] 0.577). However, inclusion of samples with catheterized urine improved the diagnostic accuracy of prediction for BC to AUC 0.995, with precision-recall AUC = 0.994. Through elimination of contaminants associated with the collection methodology among all cohorts, our study identified increased abundance of polycyclic aromatic hydrocarbon (PAH)-degrading bacteria Sphingomonas, Acinetobacter, Micrococcus, Pseudomonas, and Ralstonia to be consistently present in BC patients. CONCLUSIONS: The microbiota of the BC population may be a reflection of PAH exposure from smoking, environmental pollutants, and ingestion. Presence of PAHs in the urine of BC patients may allow for a unique metabolic niche and provide necessary metabolic resources where other bacteria are not able to flourish. Furthermore, we found that while compositional differences are associated with geography more than with disease, many are driven by the collection methodology. PATIENT SUMMARY: The goal of our study was to compare the urine microbiome of bladder cancer patients with that of healthy controls and evaluate any potential bacteria that may be more likely to be found in patients with bladder cancer. Our study is unique as it evaluates this across multiple countries, to find a common pattern. After we removed some of the contamination, we were able to localize several key bacteria that are more likely to be found in the urine of bladder cancer patients. These bacteria all share their ability to break down tobacco carcinogens.

Surgical Outcomes at a Single Institution of Infrapubic Insertion of Malleable Penile Prosthesis in Transmen.

OBJECTIVE: To describe our technique for the infrapubic approach for malleable penile prosthesis (MPP) insertion after phalloplasty in transgender men and review surgical outcomes. METHODS: The infrapubic prosthesis insertion technique involves a horizontal incision anterior to the pubic symphysis, allowing dissection of the neophallus tract and anchor site on the pubic symphysis. Surgical outcomes by a single surgeon using a Spectra or Genesis MPP between October 2017 and May 2022 were retrospectively reviewed. Complications were categorized into erosions, infections, device detachment, device malposition, pain or activity limitation, urethral injury, and flap loss. Implant survival kinetics were assessed by evaluating time to surgical revision. RESULTS: Forty patients underwent infrapubic MPP insertion; 35 patients had a prior radial forearm free flap (RFFF) and 5 had a prior anterolateral thigh flap (ALT) phalloplasty. Of 30 patients who maintained follow-up, mean follow-up was 34.9 months. Complications were not mutually exclusive, with 7 implant detachments from the anchor site, 3 malpositions, 2 with pain/activity limitation, and 1 infection. Surgical revision was required in 12/30 patients (40%). There were no neophallus erosions, flap loss, nor urethral injuries. More complications occurred with the Spectra (9/17 or 53%) than the Genesis MPP (3/13 or 23%), but this was not statistically significant (P = .10). CONCLUSION: Infrapubic insertion in transmen after phalloplasty using commercially available MPPs is safe compared with other post-phalloplasty penile prosthesis insertion techniques, with similarly high surgical revision rates. Further study of techniques is needed to improve outcomes after penile prosthesis insertion in transmen.

Characterization of Changes in Penile Microbiome Following Pediatric Circumcision.

BACKGROUND: While microbiome and host regulation contribute independently to many disease states, it is unclear how circumcision in pediatric population influences subsequent changes in penile microbiome. OBJECTIVE: Our study aims to analyze jointly paired taxonomic profiles and assess pathways implicated in inflammation, barrier protection, and energy metabolism. DESIGN, SETTING, AND PARTICIPANTS: We analyzed 11 paired samples, periurethral collection, before and after circumcision, to generate microbiome and mycobiome profiling. Sample preparation of 16S ribosomal RNA and internal transcribed spacer sequencing was adapted from the methods developed by the National Institutes of Health Human Microbiome Project. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: We obtained the predictive functional attributes of the microbial communities between samples using Silva-Tax4Fun and the Greengenes-Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) approach. The predictive functioning of the microbial communities was determined by linearly combining the normalized taxonomic abundances into the precomputed association matrix of Kyoto Encyclopedia of Genes and Genomes orthology reference profiles. RESULTS AND LIMITATIONS: Several notable microbiome and mycobiome compositional differences were observed between pre- and postcircumcision patients. Pairwise comparisons across taxa revealed a significant decrease (p < 0.05, false discovery rate corrected) of microbiome organisms (Clostridiales, Bacteroidales, and Campylobacterales) and mycobiome (Saccharomycetales and Pleosporales) following circumcision. A total of 14 pathways were found to differ in abundance between the pre- and postcircumcision groups (p < 0.005, false discovery rate <0.1 and linear discriminant analysis score >3; five enriched and nine depleted). The pathways reduced after circumcision were mostly involved with amino acid and glucose metabolism, while pathways prior to circumcision were enriched in genetic information processing and transcription processes. As expected, enrichment in methyl-accepting chemotaxis protein, an integral membrane protein involved in directed motility of microbes to chemical cues and environment, occurred prior to circumcision, while the filamentous hemagglutinin pathway (a strong immunogenic protein) was depleted after circumcision CONCLUSIONS: Our results offer greater insight into the host-microbiota relationship of penile circumcision and may serve to lay the groundwork for future studies focused on drivers of inflammation, infection, and oncogenesis. PATIENT SUMMARY: Our study showed a significant reduction in bacteria and fungi after circumcision, particularly anaerobic bacteria, which are known to be potential inducers of inflammation and cancer. This is the first study of its kind showing the changes in microbiome after circumcision, and some of the changes that occur in healthy infants after circumcision that may explain the differences in cancer and inflammatory disorders in adulthood.

Comparison of Morphological and Histological Characteristics of Human and Sheep: Sheep as a Potential Model for Testing Midurethral Slings in vivo.

INTRODUCTION: The sheep was evaluated as a potential model for preclinical evaluation of urethral slings in vivo based on: (1) anatomical measurements of the sheep vagina and (2) histological tissue integration and host response to polypropylene (PP) slings. METHODS: Eight female, multiparous sheep were utilized. Three of 8 animals underwent surgery mimicking human tension-free vaginal tape protocols for midurethral slings and were euthanized at 6 months. The following measurements were obtained: vaginal length, maximum vaginal width with retraction, symphysis pubis length, and distance from the pubic bone to incision. Explanted sling samples from sheep and human were stained with hematoxylin and eosin for host reaction assessment. RESULTS: Geometric measurements were similar between humans and sheep. Sheep vaginal anatomy allowed sling placement similar to procedures in human surgeries, and all sheep recovered without problems. Comparative histology between the sheep and human indicated similar host reaction and collagen deposition around implants, confirming suitability of the sheep model for biomaterial response assessment. CONCLUSION: Sheep vaginal length is comparable to humans. Tissue integration and host response to PP slings showed chronic inflammation with rich collagen deposition around the material in both sheep and human specimens, highlighting the sheep as a potential animal model for preclinical testing of midurethral slings.

A systematic review and in silico study of potential genetic markers implicated in cases of overactive bladder.

OBJECTIVE: The contribution of genetic factors to the presence of an overactive bladder is recognized. This study aimed to (1) assemble and synthesize available data from studies assessing differential gene expression in patients with overactive bladder vs controls without overactive bladder and (2) determine possible correlations and functional pathways between genes. DATA SOURCES: We searched PubMed, Ovid or Medline, and Wiley Cochrane Central Register of Controlled Trials databases between January 1, 2000, and December 15, 2021. STUDY ELIGIBILITY CRITERIA: Studies were included if gene expression was detected and quantified using molecular approaches performed on human bladder tissue specimens directly and excluded if the gene expression analysis was carried out from blood and urine specimens alone. METHODS: A systematic review was completed to identify publications that reported differently expressed gene candidates among patients with overactive bladder vs healthy individuals. Gene networking connections and pathway analysis were performed employing Metascape software, where inputs were identified from our systematic review of differentially expressed genes in overactive bladder. RESULTS: A total of 9 studies were included in the final analysis and 11 genes were identified as being up-regulated (purinergic receptor P2X 2 [P2RX2], smoothelin [SMTN], growth-associated protein 43 [GAP43], transient receptor potential cation channel subfamily M member 8 [TRPM8], cadherin 11 [CDH1], gap junction protein gamma 1 [GJC1], cholinergic receptor muscarinic 2 [CHRM2], cholinergic receptor muscarinic 3 [CHRM3], and transient receptor potential cation channel subfamily V member 4 [TRPV4]) or down-regulated (purinergic receptor P2X 2 [P2RX3] and purinergic receptor P2X 5 [P2RX5]) in patients with overactive bladder. Gene network analysis showed that genes are involved in chemical synaptic transmission, smooth muscle contraction, blood circulation, and response to temperature stimulus. Network analysis demonstrated a significant genetic interaction between TRPV4, TRPM8, P2RX3, and PR2X2 genes. CONCLUSION: Outcomes of this systematic review highlighted potential biomarkers for treatment efficacy and have laid the groundwork for developing future gene therapies for overactive bladder in clinical settings.

Human Gut Mycobiome and Fungal Community Interaction: The Unknown Musketeer in the Chemotherapy Response Status in Bladder Cancer.

Background: Until recently, the properties of microbiome and mycobiome in humans and its relevance to disease have largely been unexplored. While the interest of microbiome and malignancy over the past few years have burgeoned with advent of new technologies, no research describing the composition of mycobiome in bladder cancer has been done. Deciphering of the metagenome and its aggregate genetic information can be used to understand the functional properties and relationships between the bacteria, fungi, and cancer. Objective: The aim of this project is to characterize the compositional range of the normal versus bladder cancer mycobiome of the gut. Design setting and participants: An internal transcribed spacer (ITS) survey of 52 fecal samples was performed to evaluate the gut mycobiome differences between noncancer controls and bladder cancer patients. Outcome measurements and statistical analysis: Our study evaluated the differences in mycobiome among patients with bladder cancer, versus matched controls. Our secondary analysis evaluated compositional differences in the gut as a function of response status with neoadjuvant chemotherapy. Data demultiplexing and classification were performed using the QIIME v.1.1.1.1 platform. The Ion Torrent-generated fungal ITS sequence data were processed using QIIME (v.1.9.1), and the reads were demultiplexed, quality filtered, and clustered into operation taxonomic units using default parameters. Alpha and beta diversity were computed and plotted in Phyloseq, principal coordinate analysis was performed on Bray-Curtis dissimilarity indices, and a one-way permutational multivariate analysis of variance was used to test for significant differences between cohorts. Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) was applied to infer functional categories associated with taxonomic composition. Results and limitations: We found distinctive mycobiome differences between control group (n = 32) and bladder cancer (n = 29) gut flora, and identified an increasing abundance of Tremellales, Hypocreales, and Dothideales. Significant differences in alpha and beta diversity were present between the groups (control vs bladder; p = 0.002), noting distinct compositions within each cohort. A subgroup analysis by sex and neoadjuvant chemotherapy status did not show any further differences in mycobiome composition and diversity. Our results indicate that the gut mycobiome may modulate tumor response to preoperative chemotherapy in bladder cancer patients. We propose that patients with a "favorable" mycobiome composition (eg, high diversity, and low abundance of Agaricomycetes and Saccharomycetes) may have enhanced systemic immune response to chemotherapy through antigen presentation. Conclusions: Our study is the first to characterize the enteric mycobiome in patients with bladder cancer and describe complex ecological network alterations, indicating complex bacteria-fungi interactions, particularly highlighted among patients with complete neoadjuvant chemotherapy response. Patient summary: Our study has demonstrated that the composition of stool mycobiome (fungal inhabitants of the gastrointestinal tract) in patients with bladder cancer is different from that in noncancer individuals. Furthermore, when evaluating how patients respond to chemotherapy given prior to their surgery, our study noted significant differences between patients who responded and those who did not.

Role of cytoreductive surgery in the era of immunotherapy.

PURPOSE OF REVIEW: The benefit of cytoreductive nephrectomy (CN) in metastatic renal cell carcinoma (mRCC) was first called into question in the tyrosine kinase inhibitors (TKIs) era. It remains undefined in the context of the recent development and approval of immune checkpoint inhibitors (ICIs) and level one evidence supporting the rapid adoption of dual ICI and combination ICI + TKI therapeutic approaches for mRCC. Our objective is to synthesize the available contemporary data regarding the safety, feasibility, and oncologic outcomes with CN for mRCC in the age of immunotherapy as well as to highlight trials in progress that will address this key knowledge gap. RECENT FINDINGS: Data from the SURTIME and CARMENA trials provided insight to guide patient selection for CN in patients with mRCC receiving TKI-based treatment strategies. At present, there is a body of retrospective data supporting the safety and oncologic efficacy of CN in carefully selected patients with mRCC in both the upfront and delayed setting. The results of ongoing trials evaluating the safety and feasibility for CN as well as optimal patient selection and sequencing strategies are eagerly awaited. SUMMARY: Although the optimal selection criteria and timing for CN remains to be established for patients with mRCC in the immunotherapy era, the available body of evidence underscores the importance of careful patient selection. Ongoing prospective studies, such as Cyto-KIK , PROBE , and NORDIC-SUN , will better define the role of CN in the rapidly evolving treatment landscape for mRCC.

A systematic review of underlying genetic factors associated with ureteropelvic junction obstruction in stenotic human tissue.

OBJECTIVE: Genetic factors are implicated in the development of ureteropelvic junction obstruction (UPJO). The aims of this study were: 1) condense and examine the existing data in studies containing information regarding differential gene expression in tissues from patients with UPJO and 2) investigate associations between genetic markers and their related pathways. MATERIALS AND METHODS: A systematic review of studies published between January 2000 and September 2021 was conducted using the following databases: Ovid/Medline, PubMed, Wiley Cochrane Central Register of Controlled Trials, Web of Science, and Scopus. Of 249 studies, 10 were included in the final analysis. The search was performed using the terms "ureteropelvic junction obstruction", "genetic", "gene", and "gene expression". Literature pertaining to differential gene expression in UPJO patients as compared to healthy controls was identified. Studies containing gene expression and quantification of molecular data carried out directly on stenotic tissue samples were selected for analysis. Gene network connections and functional analyses were then determined using MetaScape software. RESULTS: From the ten studies identified for analysis, fifteen genes were noted as differentially expressed. In UPJO patients, nine genes were upregulated (ET1, ACTA2, MCP-1, TGFB1, NFKB1, IL-6, HIF1A, S100A1, SYP) and six were downregulated (ADM, NOS2, EGF, PDGFRA, UCHL1, NGFR). These genes were principally involved in HIF-1 signaling pathway, blood vessel development, positive regulation of signaling receptor activity, and Ras signaling pathway. CONCLUSIONS: A potential link exists between genes related to hypoxia, excessive fibrous tissue formation, and inflammation in the development of UPJO, and these connections merit more detailed, tissue level investigations in UPJO patients. The outcomes of this systematic review may lay the groundwork for the development of future targeted therapies and novel biomarker detection for treatments, early detection, and possible prediction and prevention of development of UPJO.

A preliminary evaluation of in vivo response to a filament-wound macroporous collagen midurethral sling in an ovine model.

Stress urinary incontinence (SUI) impacts ~1/3 of women over age 50. Negative publicity around PP meshes used in pelvic prolapse repair drives the need for identifying alternative biomaterials for SUI repair. Our study evaluated in vivo response to collagen sling implanted in an ovine model. Electrocompacted collagen threads were filament wound as slings and crosslinked in genipin. Collagen slings were implanted suburethrally mimicking the transvaginal tape technique. Main study groups were: Collagen sling (n = 3, 6 months) and PP sling (n = 3, 6 months). Collagen sling was also tested at 3-weeks (n = 1) to observe early-stage tissue response and 1-year (n = 2) to assess biomaterial longevity in a preliminary capacity. Collagen slings healed to a fibrous ligament texture at 6 months and maintained such texture to 1 year. Histological scoring indicated biocompatible responses to collagen slings with no adverse events. All study groups exhibited complete tissue ingrowth and interstitial de novo collagen deposition at all time points. Collagen threads induced orderly de novo collagen deposition that was aligned along long axes of threads. Tissue infiltrated collagen slings that were explanted at 6 and 12 months presented similar structural strength with native tissues such as vagina and fascia, and PP (Lynx) slings (p > .05). With the limitation of low number of animals per time point in hindsight, this preliminary study justifies evaluation of collagen slings in a larger sample size of animals, particularly to assess persistence of ligamentous tissue response over longer durations than 1-year.

Mesenchymal Stem Cell Delivery via Topographically Tenoinductive Collagen Biotextile Enhances Regeneration of Segmental Tendon Defects.

BACKGROUND: Successful management of massive rotator cuff (RC) tendon tears represents a treatment challenge because of the limited intrinsic healing capacity of native tendons and the risk of repair failure. Biologic augmentation of massive RC tears utilizing scaffolds-capable of regenerating bulk tendon tissue to achieve a mechanically functional repair-represents an area of increasing clinical interest. PURPOSE: To investigate the histological and biomechanical outcomes after the use of a novel biologic scaffold fabricated from woven electrochemically aligned collagen (ELAC) threads as a suture-holding, fully load-bearing, defect-bridging scaffold with or without mesenchymal stem cells (MSCs) compared with direct repair in the treatment of critically sized RC defects using a rabbit model. STUDY DESIGN: Controlled laboratory study. METHODS: A total of 34 New Zealand White rabbits underwent iatrogenic creation of a critically sized defect (6 mm) in the infraspinatus tendon of 1 shoulder, with the contralateral shoulder utilized as an intact control. Specimens were divided into 4 groups: (1) gap-negative control without repair; (2) direct repair of the infraspinatus tendon-operative control; (3) tendon repair using ELAC; and (4) tendon repair using ELAC + MSCs. Repair outcomes were assessed at 6 months using micro-computed tomography, biomechanical testing, histology, and immunohistochemistry. RESULTS: Specimens treated with ELAC demonstrated significantly less tendon retraction when compared with the direct repair group specimens (P = .014). ELAC + MSCs possessed comparable biomechanical strength (178 ± 50 N) to intact control shoulders (199 ± 35 N) (P = .554). Histological analyses demonstrated abundant, well-aligned de novo collagen around ELAC threads in both the ELAC and the ELAC + MSC shoulders, with ELAC + MSC specimens demonstrating increased ELAC resorption (7% vs 37%, respectively; P = .002). The presence of extracellular matrix components, collagen type I, and tenomodulin, indicating tendon-like tissue formation, was appreciated in both the ELAC and the ELAC + MSC groups. CONCLUSION: The application of MSCs to ELAC scaffolds improved biomechanical and histological outcomes when compared with direct repair for the treatment of critically sized defects of the RC in a rabbit model. CLINICAL RELEVANCE: This study demonstrates the feasibility of repairing segmental tendon defects with a load-bearing, collagen biotextile in an animal model, showing the potential applicability of RC repair supplementation using allogeneic stem cells.

In Vivo Delivery of M0, M1, and M2 Macrophage Subtypes via Genipin-Cross-Linked Collagen Biotextile.

Developing strategies to regulate the immune response poses significant challenges with respect to the clinical translation of tissue-engineered scaffolds. Prominent advancements have been made relating to macrophage-based therapies and biomaterials. Macrophages exhibit the potential to influence healing trajectory, and predominance of particular subtypes during early onset of healing influences repair outcomes. This study evaluated short- and long-term healing response and postoperative mechanical properties of genipin-cross-linked, electrochemically aligned collagen biotextiles with comparative administration of M0, M1, and M2 subtypes. Irrespective of macrophage subtype seeded, all the groups demonstrated existence of M2 macrophages at both time points as typified by arginase and Ym-1 expressions, and distinct absence of M1 macrophages, as indicated by lack of inducible nitric oxide synthase (iNOS) and interleukin-1ß expression in all the groups for both time points. M2 macrophage-seeded collagen biotextiles revealed promising host tissue responses, such as reduced fibrous capsule thickness and minimal granulation tissue formation. Furthermore, the M2-seeded group displayed more abundant interstitial collagen deposition following degradation of the collagen threads. M2 macrophage supplementation improved structural and mechanical properties at the tissue and cellular level as indicated by increased modulus and stiffness. This study demonstrates improved biomechanical and histological outcomes following incorporation of M2 macrophages into genipin-cross-linked collagen biotextiles for tissue repair and offers future strategies focused on connective tissue regeneration. Impact statement Macrophages exhibit significant plasticity with complex phenotypes ranging from proinflammatory (M1) to proregenerative (M2). They release cytokines and chemokines governing immunological stability, inflammation resolution, and tissue healing and regeneration. However, utilization of macrophages as therapeutic tools for tissue engineering remains limited. In this study, genipin-cross-linked collagen biotextiles were employed to deliver M0, M1, and M2 macrophages and evaluate tissue responses and postsurgical mechanical properties in vivo. M2-seeded collagen biotextiles showed reduced fibrous capsule and favorable healing response. These outcomes shed new light on designing tissue-engineered constructs that offer a novel cell-based therapeutic approach for applications requiring structural augmentation.

Gene network profiling in muscle-invasive bladder cancer: A systematic review and meta-analysis.

BACKGROUND: Determining meta-analysis of transcriptional profiling of muscle-invasive bladder cancer (MIBC) through Gene Expression Omnibus (GEO) datasets has not been investigated. This study aims to define gene expression profiles in MIBC and to identify potential candidate genes and pathways. OBJECTIVES: To review and evaluate gene expression studies in MIBC through publicly available RNA sequencing (RNA-Seq) and microarray data in order to identify potential prognostic and therapeutic targets for MIBC. METHODS: A systematic literature search of the Ovid MEDLINE, PubMed, and Wiley Cochrane Central Register of Controlled Trials databases was performed using the terms "gene," "gene expression," and "bladder cancer" January 1, 1990 through March 2021 focused on populations with MIBC. RESULTS: In the final analysis, GEO datasets were included. Fixed effect model was employed in the meta-analysis. Gene networking connections and gene-set functional analyses of the identified genes as differentially expressed in MIBC were performed using ImaGEO and GeneMANIA software. A heatmap for the upregulated and downregulated genes was generated along with the correlated pathways. CONCLUSION: A total of 9 genes were reported in this analysis. Six genes were reported as upregulated (ProTα, SPINT1, UBE2E1, RAB25, KPNB1, HDAC1) and 3 genes as downregulated (NUP188, IPO13, NUP124). Genes were found to be involved in "ubiquitin mediated proteolysis," "protein processing in endoplasmic reticulum," "transcriptional misregulation in cancer," and "RNA transport" pathways.