Profiling the Urinary Microbiota in Male Patients With Bladder Cancer in China

Heterogeneity of modulatory immune microenvironment in bladder cancer

Urinary bladder cancer (UBC) is the ninth most common cancer worldwide. The intra-tumor heterogeneity of the UBC microenvironment explains the variances in response to therapy among patients. Tumor immune microenvironment (TIME) is based on the balance between anti-tumor and pro-tumorigenic immunity that eventually determines the tumor fate. This review addresses the recent insights of the cytokines, immune checkpoints, receptors, enzymes, proteins, RNAs, cancer stem cells (CSCs), tissue-resident cells, growth factors, epithelial-mesenchymal transition, microbiological cofactor, and paracrine action of cancer cells that mutually cross-talk within the TIME. In-depth balance and alteration of these factors influence the TIME and the overall tumor progression. This, in turn, highlights the prospects of the new era of manipulating these co-factors for improving the diagnosis, prognosis, and treatment of UBC. CONCLUSION: The heterogenic architecture of the TIME orchestrates the fate of the tumor. Nevertheless, recognizing the mutual cross-talk between these key players seems useful in prognostic and therapeutic approaches.

Exploring the prognostic and predictive potential of bacterial biomarkers in non-gastrointestinal solid tumors

INTRODUCTION

Standard clinical parameters like tumor size, age, lymph node status, and molecular markers are used to predict progression risk and treatment response. However, exploring additional markers that reflect underlying biology could offer a more comprehensive understanding of the tumor microenvironment (TME). The TME influences tumor development, progression, disease severity, and survival, with tumor-associated bacteria posited to play significant roles. Studies on tumor-associated microbiota have focused on high bacterial-load sites such as the gut, oral cavity, and stomach, but interest is growing in non-gastrointestinal (GI) solid tumors, such as breast, lung, and pancreas. Microbe-based biomarkers, including Helicobacter pylori, human papillomavirus (HPV), and hepatitis B and C viruses, have proven valuable in predicting gastric, cervical, and renal cancers.

AREAS COVERED

Potential of prognostic and predictive bacterial biomarkers in non-GI solid tumors and the methodologies used.

EXPERT OPINION

Advances in techniques like 16S rRNA gene sequencing, qPCR, immunostaining, and in situ hybridization have enabled detailed analysis of difficult-to-culture microbes in solid tumors. However, to ensure reliable results, it is critical to standardize protocols, accurately align reads, address contamination, and maintain proper sample handling. This will pave the way for developing reliable bacterial markers that enhance prognosis, prediction, and personalized treatment planning.

Tumor microbiome: roles in tumor initiation, progression, and therapy

Over the past few years, the tumor microbiome is increasingly recognized for its multifaceted involvement in cancer initiation, progression, and metastasis. With the application of 16S ribosomal ribonucleic acid (16S rRNA) sequencing, the intratumoral microbiome, also referred to as tumor-intrinsic or tumor-resident microbiome, has also been found to play a significant role in the tumor microenvironment (TME). Understanding their complex functions is critical for identifying new therapeutic avenues and improving treatment outcomes. This review first summarizes the origins and composition of these microbial communities, emphasizing their adapted diversity across a diverse range of tumor types and stages. Moreover, we outline the general mechanisms by which specific microbes induce tumor initiation, including the activation of carcinogenic pathways, deoxyribonucleic acid (DNA) damage, epigenetic modifications, and chronic inflammation. We further propose the tumor microbiome may evade immunity and promote angiogenesis to support tumor progression, while uncovering specific microbial influences on each step of the metastatic cascade, such as invasion, circulation, and seeding in secondary sites. Additionally, tumor microbiome is closely associated with drug resistance and influences therapeutic efficacy by modulating immune responses, drug metabolism, and apoptotic pathways. Furthermore, we explore innovative microbe-based therapeutic strategies, such as engineered bacteria, oncolytic virotherapy, and other modalities aimed at enhancing immunotherapeutic efficacy, paving the way for microbiome-centered cancer treatment frameworks.

Preventive effects of kefir on colon tumor development in Wistar rats: gut microbiota critical role

To clarify the effects of kefir in critical periods of development in adult diseases, we study the effects of kefir intake during early life on gut microbiota and prevention of colorectal carcinogenesis in adulthood. Lactating Wistar rats were divided into three groups: control (C), kefir lactation (KL), and kefir puberty (KP) groups. The C and KP groups received 1 mL of water/day; KL dams received kefir milk daily (108 CFU/mL) during lactation. After weaning (postnatal day 21), KP pups received kefir treatment until 60 days. At 67 days old, colorectal carcinogenesis was induced through intraperitoneal injection of 1, 2-dimethylhydrazine. The gut microbiota composition were analyzed by 16S rRNA gene sequencing and DESeq2 (differential abundance method), revealing significant differences in bacterial abundances between the kefir consumption periods. Maternal kefir intake strong anticancer power, suppressed tumors in adult offspring and reduced the relative risk of offspring tumor development. The gut microbiota in cecal samples of the KL group was enriched with Lactobacillus, Romboutsia, and Blautia. In contrast, control animals were enriched with Acinetobacter. The administration of kefir during critical periods of development, with emphasis on lactation, affected the gut microbial community structure to promote host benefits. Pearson analysis indicated positive correlation between tumor number with IL-1 levels. Therefore, the probiotic fermented food intake in early life may be effective as chemopreventive potential against colon tumor development, especially in lactation period.

Intra-tumoral sphingobacterium multivorum promotes triple-negative breast cancer progression by suppressing tumor immunosurveillance

BACKGROUND

Intratumor-resident bacteria represent an integral component of the tumor microenvironment (TME). Microbial dysbiosis, which refers to an imbalance in the bacterial composition and bacterial metabolic activities, plays an important role in regulating breast cancer development and progression. However, the impact of specific intratumor-resident bacteria on tumor progression and their underlying mechanisms remain elusive.

METHODS

16S rDNA gene sequencing was used to analyze the cancerous and paracancerous tissues from breast cancer patients. The mouse models of bearing 4T1 cell tumors were employed to assess the influence of bacterial colonization on tumor growth. Tissue infiltration of regulatory T (Treg) cells and CD8+ T cells was evaluated through immunohistochemistry and flow cytometric analysis. Comparative metabolite profiling in mice tumors was conducted using targeted metabolomics. Differential genes of tumor cells stimulated by bacteria were analyzed by transcriptomics and validated by qPCR assay.

RESULTS

We found that Sphingobacterium displayed high abundance in cancerous tissues. Intra-tumoral colonization of Sphingobacterium multivorum (S. multivorum) promoted tumor progression in 4T1 tumor-bearing mice. Moreover, S. multivorum diminished the therapeutic efficacy of αPD-1 mAb, which was associated with the increase of regulatory T cell (Treg) infiltration, and decrese of the CD8+ T cell infiltration. Targeted metabolomics revealed a conspicuous reduction of propionylcarnitine in tumors colonized by S. multivorum Furthermore, the combination of metabolite propionylcarnitine and S. multivorum shown to suppress tumor growth compared that in S. multivorum alone in vivo. Mechanistically, S. multivorum promoted the secretion of chemokines CCL20 and CXCL8 from tumor cells. CCL20 secreted into the TME facilitated the recruitment of Treg cells and reduced CD8+ T cell infiltration, thus promoting tumor immune escape.

CONCLUSIONS

This study reveals S. multivorum suppresses immune surveillance within the TME, thereby promoting breast cancer progression.

Microbiome and bladder cancer: the role of probiotics in treatment

Bladder cancer (BCa) remains a significant global health challenge, with increasing interest in the role of the bladder microbiome in its pathogenesis, progression and treatment outcomes. The complex relationship between bladder cancer and the microbiome, as well as the potential impact of probiotics on treatment effectiveness, is currently under investigation. Research suggests that the microbiota may influence BCa recurrence prevention and enhance the efficacy of the Bacillus Calmette-Guérin (BCG) vaccine. Recent studies reveal differences in the bladder microbiome between individuals without bladder cancer and those with the disease. In the healthy bladder, Streptococcus and Lactobacillus are consistently identified as the most prevalent genera. However, in men, the predominant bacterial genera are Staphylococcus, Corynebacterium and Streptococcus, while in women with bladder cancer, Gardnerella and Lactobacillus are dominant. Probiotics, particularly Lactobacillus spp., can exhibit anti-tumor properties by competing with pathogenic strains involved in carcinogenesis or by producing regulatory substances. They regulate cancer signaling, induce apoptosis, inhibit mutagenic activity, downregulate oncogene expression, induce autophagy, inhibit kinases, reactivate tumor suppressors and prevent metastasis. These mechanisms have shown promising results in both preclinical and some clinical studies.

HPV-Associated Gene Signatures in Bladder Cancer: A Comprehensive Prognostic Model and its Implications in Immunotherapy

Background: Evidence increasingly indicates that HPV infection plays a pivotal role in the initiation and progression of bladder cancer (BC). Yet, determining the predictive value of HPV-associated genes in BC remains challenging. Methods: We identified differentially expressed HPV-associated genes of BC patients from the TCGA and GEO databases. We screened prognostic genes using COX and LASSO regression, subsequently establishing a risk prediction model. The model's precision and clinical relevance were gauged using Kaplan-Meier survival analyses and ROC curves. Functional enrichment, immune cell infiltration, and drug sensitivity analyses were performed across both high-risk and low-risk sets. PCR assays were utilized to measure the expression levels of genes. Results: We identified 13 HPV-associated genes for our risk model. Among these, FLRT2, HOXC5, LDLR, SCD, GRM7, DSC1, EMP1, and HMGA1 were identified as risk contributors, while LPA, SERPINA6, ZNF124, ETV7, and SCO2 were deemed protective. Cox regression analysis verified that our model provides an independent prediction of overall survival (OS) in bladder cancer (BC) patients. Gene Ontology (GO) analysis revealed predominant gene enrichment in wound healing, extracellular matrix composition, and collagen-rich extracellular matrices. KEGG pathway analysis highlighted primary enrichment areas, including focal adhesion, the PI3K-Akt signalling pathway, and ECM-receptor interaction. Risk scores were correlated with tumor microenvironment (TME) scores, immune cell infiltration, and sensitivities to both chemotherapy and immunotherapy. Conclusion: We have formulated a risk-assessment model pinpointing 13 central HPV-associated genes in BC. These genes present potential as prognostic indicators and therapeutic targets, emphasizing the intertwined relationship between HPV-induced BC progression and the immune landscape.

Microbiome in urologic neoplasms: focusing on tumor immunity

Urological tumors are an important disease affecting global human health, and their pathogenesis and treatment have been the focus of medical research. With the in - depth study of microbiomics, the role of the microbiome in urological tumors has gradually attracted attention. However, the current research on tumor - associated microorganisms mostly focuses on one type or one site, and currently, there is a lack of attention to the microbiome in the immunity and immunotherapy of urological tumors. Therefore, in this paper, we systematically review the distribution characteristics of the microbiome (including microorganisms in the gut, urine, and tumor tissues) in urologic tumors, the relationship with disease prognosis, and the potential mechanisms of microbial roles in immunotherapy. In particular, we focus on the molecular mechanisms by which the microbiome at different sites influences tumor immunity through multiple "messengers" and pathways. We aim to further deepen the understanding of microbiome mechanisms in urologic tumors, and also point out the direction for the future development of immunotherapy for urologic tumors.

State of the Art: The Microbiome in Bladder Cancer

This review assesses the current understanding of the relationship between the human microbiome and BCa. Recognizing how the microbiome affects the tumor microenvironment provides valuable insights into cancer biology, potentially uncovering interactions that could be leveraged to develop innovative therapeutic approaches. By clarifying these intricate microbial-tumor dynamics, novel targets for microbiome-based interventions can be identified, ultimately improving treatment effectiveness and patient outcomes. Current literature lacks comprehensive insights into the effects of BCa treatment on the microbiome and the prevalence of immunotherapy-related toxicities. Further research into the microbiome's role in BCa development could bridge the gap between fundamental research and therapeutic applications. Implementing microbiome surveillance, metagenomic sequencing, and metabolomics in clinical trials could deepen our understanding of BCa and its treatment. This review explores the existing understanding of the urine, tissue, and gut microbiomes and their connections to BCa. Enhanced knowledge of these relationships can pave the way for future research to identify reliable disease predictors, prognostic markers, and novel therapeutic targets.

A comparison of male and female renal pelvis urobiome of unilateral stone formers using 2bRAD-M

BACKGROUND

Urolithiasis is a prevalent urological ailment characterized by increasing prevalence and recurrence rates, resulting in substantial social and economic burden. While men exhibit an incidence rate nearly twice that of women, this gender disparity is gradually diminishing. Nevertheless, the mechanisms underlying this condition remain incompletely elucidated. The identification of the urinary microbiome (urobiome) has provided a fresh perspective on urolithiasis. This study aimed to analyze the urobiome of unilateral stone formers in the renal pelvis and evaluate the variations in microbial diversity and community composition between males and females.

METHODS

Renal pelvis urine samples were obtained from a cohort of 21 male and 9 female patients and subsequently subjected to taxonomic and functional analysis using 2bRAD sequencing for Microbiome (2bRAD-M). The collected samples were categorized into four distinct groups, namely the stone side of males (SM), stone side of females (SF), non-stone side of males (NSM), and non-stone side of females (NSF).

RESULTS

Through the application of beta diversity analysis, dissimilarity was observed between NSM and NSF. Additionally, NSF exhibited a higher abundance of microbial populations, and a total of 29 distinct species were identified as differentially present between NSM and NSF using LEfSe. Lactobacillus iners, Atopobium deltae, Lawsonella clevelandensis, and Meyerozyma guilliermondii exhibited enrichment in the SF group compared to the SM group. Furthermore, we identified distinct species that differed between the SM and NSM groups, as well as the SF and NSF groups. Besides, we conducted COG annotation and KEGG pathway predictions, revealing significant differences in urobiome function across the different groups.

CONCLUSION

Variations in microbial community composition and predicted functions were observed among the various groups. Future research could potentially leverage the urobiome to personalize urolithiasis treatment based on individual microbial characteristics, taking into account gender-specific differences.

Tumor-Resident Microbiota-Based Risk Model Predicts Neoadjuvant Therapy Response of Locally Advanced Esophageal Squamous Cell Carcinoma Patients

Few predictive biomarkers exist for identifying patients who may benefit from neoadjuvant therapy (NAT). The intratumoral microbial composition is comprehensively profiled to predict the efficacy and prognosis of patients with esophageal squamous cell carcinoma (ESCC) who underwent NAT and curative esophagectomy. Least Absolute Shrinkage and Selection Operator (LASSO) regression analysis is conducted to screen for the most closely related microbiota and develop a microbiota-based risk prediction (MRP) model on the genera of TM7x, Sphingobacterium, and Prevotella. The predictive accuracy and prognostic value of the MRP model across multiple centers are validated. The MRP model demonstrates good predictive accuracy for therapeutic responses in the training, validation, and independent validation sets. The MRP model also predicts disease-free survival (p = 0.00074 in the internal validation set and p = 0.0017 in the independent validation set) and overall survival (p = 0.00023 in the internal validation set and p = 0.11 in the independent validation set) of patients. The MRP-plus model basing on MRP, tumor stage, and tumor size can also predict the patients who can benefit from NAT. In conclusion, the developed MRP and MRP-plus models may function as promising biomarkers and prognostic indicators accessible at the time of diagnosis.

Comparison of Tissue and Urine Microbiota in Male, Intervention Naive Patients with and without Non-Invasive Bladder Cancer

INTRODUCTION

To investigate the presence of dysbiosis in patients with naive bladder cancer.

METHODS

Twelve male patients with non-invasive bladder cancer and twelve age-matched healthy males had midstream urine and tissue samples taken. A history of endourological interventions was determined as an exclusion criterion, ensuring that the study was designed solely with naïve participants. The bacterial 16s ribosomal RNA V3-V4 regions were used to examine urine and tissue samples. We compared the microbiota composition of the bladder cancer and control groups.

RESULTS

Escherichia Shigella (p < 0.001), Staphylococcus (p < 0.001), Delftia (p < 0.001), Acinetobacter (p < 0.001), Corynebacterium (p < 0.001), and Enhydrobacter (p < 0.001) were abundant in bladder cancer tissue samples. Escherichia Shigella (p < 0.001), Ureaplasma (p < 0.001), Lactobacillus (p = 0.005), Stenotrophomonas (p < 0.001), Streptococcus (p < 0.001), Corynebacterium (p < 0.001), and Prevotella (p = 0.039) were abundant in bladder cancer urine samples. Midstream urine has a sensitivity of 83% for detecting dysbiotic bacteria in cancer tissue.

CONCLUSIONS

Our research is the first microbiota study of bladder cancer done with naive patients who have never had an endourological intervention. Escherichia Shigella, Staphylococcus, Acinetobacter, Enhydrobacter, Delftia, Corynebacterium, and Pseudomonas were detected as dysbiotic bacteria in bladder cancer. The sensitivity of the midstream urine sample in detecting dysbiosis in tissue is 83%.

Dysbiosis in Human Urinary Microbiota May Differentiate Patients with a Bladder Cancer

Recent interest in noninvasive diagnostic approaches has highlighted the potential of urinary microbiota as a novel biomarker for bladder cancer. This study investigated the urinary microbiota of 30 bladder cancer patients and 32 healthy controls using a specific NGS protocol that sequences eight hypervariable regions of the 16S rRNA gene, providing detailed insights into urinary microbiota composition. The relative abundance of microbial compositions in urine samples from cancer patients and healthy controls was analyzed across various taxonomic levels. No notable differences were highlighted at the phylum, class, order, and family levels. At the genus level, 53% of detected genera were represented in either cancer patients or healthy controls. Microbial diversity was significantly lower in cancer patients. The differential analysis identified five genera, Rhodanobacter, Cutibacterium, Alloscardovia, Moryella, and Anaeroglobus, that were significantly more abundant in cancer patients. Notably, Rhodanobacter was present in 20 cancer samples but absent in healthy controls. Conversely, 40 genera, including Lactobacillus, Propionibacterium, and Bifidobacterium, exhibited reduced abundance in cancer patients. These findings suggest that some genera may serve as potential biomarkers for bladder cancer, highlighting the need for further research to explore their roles in disease pathogenesis and their potential applications in diagnostics and therapeutics.

Microbial mysteries: Staphylococcus aureus and the enigma of carcinogenesis

Staphylococcus aureus, a common human pathogen, has long been the focus of scientific investigation due to its association with various infections. However, recent research has unveiled a tantalizing enigma surrounding this bacterium and its potential involvement in carcinogenesis. Chronic S. aureus infections have been linked to an elevated risk of certain cancers, including skin cancer and oral cancer. This review explores the current state of knowledge regarding this connection, examining epidemiological evidence, pathogenic mechanisms, and biological interactions that suggest a correlation. Although initial studies point to a possible link, the precise mechanisms through which S. aureus may contribute to cancer development remain elusive. Emerging evidence suggests that the chronic inflammation induced by persistent S. aureus infections may create a tumor-promoting environment. This inflammation can lead to DNA damage, disrupt cellular signaling pathways, and generate an immunosuppressive microenvironment conducive to cancer progression. Additionally, S. aureus produces a variety of toxins and metabolites that can directly interact with host cells, potentially inducing oncogenic transformations. Despite these insights, significant gaps remain in our understanding of the exact biological processes involved. This review emphasizes the urgent need for more comprehensive research to clarify these microbiological mysteries. Understanding the role of S. aureus in cancer development could lead to novel strategies for cancer prevention and treatment, potentially transforming therapeutic approaches.

Insights into the Interplay between the Urinary Microbiome and Bladder Cancer: A Comprehensive Review

New insights in the urinary microbiome have led to a better understanding being built of the shifts in bacterial representations from health to disease; these hold promise as markers for diagnosis and therapeutic responses. Although several efforts have been made to identify a "core urinary microbiome", different fingerprints have been identified in men and women that shift with age. The main bacterial groups overall include Firmicutes, Actinobacteria, Fusobacteria, and Bacteroidetes. Although patients with bladder cancer have a microbiome that is similar to that of healthy individuals, differences have been observed at the species level with Fusobacterium nucleatum and Ralstonia, and at the genus level with Cutibacterium. Different bacterial representations may influence extracellular matrix composition, affecting tumor metastatic spreading and tumorigenic metalloproteinase expression. Furthermore, gene expression affecting targets of immune therapy, such as PD-L1, has been associated with changes in bacterial representations and therapeutic response to BCG. This comprehensive review aims to examine the influence of the urinary microbiome in bladder cancer.

Targeting gut and intratumoral microbiota: a novel strategy to improve therapy resistance in cancer with a focus on urologic tumors

INTRODUCTION

Growing attention has been drawn to urologic tumors due to their rising incidence and suboptimal clinical treatment outcomes. Cancer therapy resistance poses a significant challenge in clinical oncology, limiting the efficacy of conventional treatments and contributing to disease progression. Recent research has unveiled a complex interplay between the host microbiota and cancer cells, highlighting the role of the microbiota in modulating therapeutic responses.

AREAS COVERED

We used the PubMed and Web of Science search engines to identify key publications in the fields of tumor progression and urologic tumor treatment, specifically focusing on the role of the microbiota. In this review, we summarize the current literature on how microbiota influence the tumor microenvironment and anti-tumor immunity, as well as their impact on treatments for urinary system malignancies, highlighting promising future applications.

EXPERT OPINION

We explore how the composition and function of the gut microbiota influence the tumor microenvironment and immune response, ultimately impacting treatment outcomes. Additionally, we discuss emerging strategies targeting the microbiota to enhance therapeutic efficacy and overcome resistance. The application of antibiotics, fecal microbiota transplantation, and oncolytic bacteria has improved tumor treatment outcomes, which provides a novel insight into developing therapeutic strategies for urologic cancer.

A review of urinary bladder microbiome in patients with bladder cancer and its implications in bladder pathogenesis

PURPOSE

The recent discovery of the urinary microbiome has led to an emerging field of investigation about the potential role of microorganisms in the pathogenesis of urinary bladder cancer. Few preliminary data have been reported so far implicating urobiome as causative and prognostic factor of bladder tumorigenesis. In the present study, a review of the current evidence is presented about microbiome composition among patients with bladder cancer and healthy individuals as well as possible implications of microbiome on urothelial carcinoma of the bladder.

METHODS

A literature review was conducted using PubMed/MEDLINE, Scopus, and the Cochrane library until December 2023. Search algorithm was constructed using the following terms and their associated Mesh terms and Boolean operators: "urinary microbiome" and "urinary microbiota". Studies written in English language, identifying, and comparing urinary microbiome among bladder cancer patients and healthy control group were included in the review.

RESULTS

A total of 2,356 reports were identified. From this total 16 articles complied with the inclusion criteria were selected for analysis. These articles represent a total of about 486 bladder cancer patients.

CONCLUSION

Recent studies revealed the colonization of the urinary tract and the bladder by micro-organisms using both enhanced culture- and molecular-based techniques for microbial characterization. However, several limitations exist in the literature decreasing the reliability of the current reports. As a result, urinary microbiome consist an ambitious era in bladder cancer research with an increasing number of evidence about its potential pathogenetic, prognostic and therapeutic role.

Urinary microbiome dysbiosis is associated with an inflammatory environment and perturbed fatty acids metabolism in the pathogenesis of bladder cancer

BACKGROUND

Bladder cancer is a common malignancy with high recurrence rate. Early diagnosis and recurrence surveillance are pivotal to patients' outcomes, which require novel minimal-invasive diagnostic tools. The urinary microbiome is associated with bladder cancer and can be used as biomarkers, but the underlying mechanism is to be fully illustrated and diagnostic performance to be improved.

METHODS

A total of 23 treatment-naïve bladder cancer patients and 9 non-cancerous subjects were enrolled into the Before group and Control group. After surgery, 10 patients from the Before group were further assigned into After group. Void mid-stream urine samples were collected and sent for 16S rDNA sequencing, targeted metabolomic profiling, and flow cytometry. Next, correlations were analyzed between microbiota, metabolites, and cytokines. Finally, receiver operating characteristic (ROC) curves of the urinary biomarkers were plotted and compared.

RESULTS

Comparing to the Control group, levels of IL-6 (p < 0.01), IL-8 (p < 0.05), and IL-10 (p < 0.05) were remarkably elevated in the Before group. The α diversity of urine microbiome was also significantly higher, with the feature microbiota positively correlated to the level of IL-6 (r = 0.58, p < 0.01). Significant differences in metabolic composition were also observed between the Before and Control groups, with fatty acids and fatty acylcarnitines enriched in the Before group. After tumor resection, cytokine levels and the overall microbiome structure in the After group remained similar to that of the Before group, but fatty acylcarnitines were significantly reduced (p < 0.05). Pathway enrichment analysis revealed beta-oxidation of fatty acids was significantly involved (p < 0.001). ROC curves showed that the biomarker panel of Actinomycetaceae + arachidonic acid + IL-6 had superior diagnostic performance, with sensitivity of 0.94 and specificity of 1.00.

CONCLUSIONS

Microbiome dysbiosis, proinflammatory environment and altered fatty acids metabolism are involved in the pathogenesis of bladder cancer, which may throw light on novel noninvasive diagnostic tool development.

Changes in the Urinary Microbiome After Transurethral Resection of Non-muscle-Invasive Bladder Cancer: Insights from a Prospective Observational Study

BACKGROUND

This study aimed to characterize the urinary and tumor microbiomes in patients with non-muscle-invasive bladder cancer (NMIBC) before and after transurethral resection of the bladder tumor (TURBT).

METHODS

This single-center prospective study included 26 samples from 11 patients with low-grade Ta papillary NMIBC. Urine samples were collected at the index TURBT and at a 1-year follow-up cystoscopy. The metagenomic analysis of bacterial and archaeal populations was performed based on the highly variable V3-V4 region of the 16S rRNA gene.

RESULTS

Phylogenetic alpha diversity of the bladder microbiome detected in urine was found to be lower at the 1-year follow-up cystoscopy compared to the time of the index TURBT (p < 0.01). Actinomyces, Candidatus cloacimonas, Sphingobacterium, Sellimonas, Fusobacterium, and Roseobacter were more differentially enriched taxa in urine at the follow-up cystoscopy than at the index TURBT. Beta diversity of urine microbiome significantly changed over time (p < 0.05). Phylogenetic alpha diversity of the microbiome was greater in tumor tissues than in paired urine samples (p<0.01). Sphingomonas, Acinetobacter, Candidatus, and Kocuria were more differentially overrepresented in tumor tissues than in urine. The enrichment of the abundance of Corynebacterium and Anaerococcus species in urine collected at TURBT was observed in patients who experienced recurrence within the follow-up period.

CONCLUSIONS

In patients with low-grade NMIBC, the urine microbiome undergoes changes over time after removal of the tumor. The microbiome detected in tumor tissues is more phylogenetically diverse than in paired urine samples collected at TURBT. The interplay between bladder microbiome, tumor microbiome, and their alterations requires further studies to elucidate their predictive value and perhaps therapeutic implications.

Breast Cancer: Extracellular Matrix and Microbiome Interactions

Breast cancer represents the most prevalent form of cancer and the leading cause of cancer-related mortality among females worldwide. It has been reported that several risk factors contribute to the appearance and progression of this disease. Despite the advancements in breast cancer treatment, a significant portion of patients with distant metastases still experiences no cure. The extracellular matrix represents a potential target for enhanced serum biomarkers in breast cancer. Furthermore, extracellular matrix degradation and epithelial-mesenchymal transition constitute the primary stages of local invasion during tumorigenesis. Additionally, the microbiome has a potential influence on diverse physiological processes. It is emerging that microbial dysbiosis is a significant element in the development and progression of various cancers, including breast cancer. Thus, a better understanding of extracellular matrix and microbiome interactions could provide novel alternatives to breast cancer treatment and management. In this review, we summarize the current evidence regarding the intricate relationship between breast cancer with the extracellular matrix and the microbiome. We discuss the arising associations and future perspectives in this field.

Dietary Features Are Associated with Differences in the Urinary Microbiome in Clinically Healthy Adult Dogs

Nutrition plays an important role in shaping the gut microbiome composition, although the impact of diet on the urinary microbiome (i.e., urobiome) remains unknown. The aim of this pilot study was to discover how nutritional features affect the diversity and composition of the urobiome in dogs. Dietary histories were obtained for 15 clinically healthy adult dogs, including limited nutrient (protein, fat, crude fiber), commercial diet brand, and dietary diversity profiles. The urine samples were collected via cystocentesis, followed by sequencing of the bacterial 16S rRNA gene. The data were analyzed to determine associations between major nutrients and dietary sources with the urobiome's composition. The protein, fat, and crude fiber contents had no statistically significant effect on the alpha or beta diversity. However, the beta diversity values differed (PERMANOVA; p = 0.017, R2 = 0.10) between dogs fed one commercial diet brand compared to dogs consuming any other brand. The beta diversity values also differed (p = 0.019, R2 = 0.10) between dogs consuming more diverse daily diets compared to those consuming less diverse diets (≥3 or <3 unique food sources, respectively). Overall, the results of this pilot study suggest that diet might impact the urobiome and support further exploration of the relationship between diet and the urobiome's composition in dogs.

Clinical Applications of the Gut Microbiome in Genitourinary Cancers

Recently recognized as one of the hallmarks of cancer, the microbiome consists of symbiotic microorganisms that play pivotal roles in carcinogenesis, the tumor microenvironment, and responses to therapy. With recent advances in microbiome metagenomic sequencing, a growing body of work has demonstrated that changes in gut microbiome composition are associated with differential responses to immune checkpoint inhibitors (ICIs) because of alterations in cytokine signaling and cytotoxic T-cell recruitment. Therefore, strategies to shape the gut microbiome into a more favorable, immunogenic profile may lead to improved responses with ICIs. Immunotherapy is commonly used in genitourinary (GU) cancers such as renal cell carcinoma, urothelial cancer, and to a limited extent, prostate cancer. However, a subset of patients do not derive clinical benefit with ICIs. Gut microbiome-based interventions are of particular interest given the potential to boost responses to ICIs in preclinical and early-phase prospective studies. Novel approaches using probiotic therapy (live bacterial supplementation) and fecal microbiota transplantation in patients with GU cancers are currently under investigation.

Microbiome Sex-Related Diversity in Non-Muscle-Invasive Urothelial Bladder Cancer

Sex-specific discrepancies in bladder cancer (BCa) are reported, and new studies imply that microbiome may partially explain the diversity. We aim to provide characterization of the bladder microbiome in both sexes diagnosed with non-muscle-invasive BCa with specific insight into cancer grade. In our study, 16S rRNA next-generation sequencing was performed on midstream urine, bladder tumor sample, and healthy-appearing bladder mucosa. Bacterial DNA was isolated using QIAamp Viral RNA Mini Kit. Metagenomic analysis was performed using hypervariable fragments of the 16S rRNA gene on Ion Torrent Personal Genome Machine platform. Of 41 sample triplets, 2153 taxa were discovered: 1739 in tumor samples, 1801 in healthy-appearing bladder mucosa and 1370 in midstream urine. Women were found to have smaller taxa richness in Chao1 index than men (p = 0.03). In comparison to low-grade tumors, patients with high-grade lesions had lower bacterial diversity and richness in urine. Significant differences between sexes in relative abundance of communities at family level were only observed in high-grade tumors.

Emerging clinical relevance of microbiome in cancer: promising biomarkers and therapeutic targets

The profound influence of microbiota in cancer initiation and progression has been under the spotlight for years, leading to numerous researches on cancer microbiome entering clinical evaluation. As promising biomarkers and therapeutic targets, the critical involvement of microbiota in cancer clinical practice has been increasingly appreciated. Here, recent progress in this field is reviewed. We describe the potential of tumor-associated microbiota as effective diagnostic and prognostic biomarkers, respectively. In addition, we highlight the relationship between microbiota and the therapeutic efficacy, toxicity, or side effects of commonly utilized treatments for cancer, including chemotherapy, radiotherapy, and immunotherapy. Given that microbial factors influence the cancer treatment outcome, we further summarize some dominating microbial interventions and discuss the hidden risks of these strategies. This review aims to provide an overview of the applications and advancements of microbes in cancer clinical relevance.

Cancer invasion and anaerobic bacteria: new insights into mechanisms

There is growing evidence that altered microbiota abundance of a range of specific anaerobic bacteria are associated with cancer, including Peptoniphilus spp., Porphyromonas spp., Fusobacterium spp., Fenollaria spp., Prevotella spp., Sneathia spp., Veillonella spp. and Anaerococcus spp. linked to multiple cancer types. In this review we explore these pathogenic associations. The mechanisms by which bacteria are known or predicted to interact with human cells are reviewed and we present an overview of the interlinked mechanisms and hypotheses of how multiple intracellular anaerobic bacterial pathogens may act together to cause host cell and tissue microenvironment changes associated with carcinogenesis and cancer cell invasion. These include combined effects on changes in cell signalling, DNA damage, cellular metabolism and immune evasion. Strategies for early detection and eradication of anaerobic cancer-associated bacterial pathogens that may prevent cancer progression are proposed.

Urinary microbiota is associated to clinicopathological features in benign prostatic hyperplasia

BACKGROUND

The urinary microbiota of patients with benign prostatic hyperplasia (BPH) has been associated with lower urinary tract symptoms (LUTS), however, little is known about urinary microbiota correlations with clinicopathological parameters associated with BPH. Here, we investigate associations between the urinary microbiota and clinical parameters of patients with BPH undergoing surgery.

METHODS

Forty-one patients with BPH undergoing surgery were recruited from two medical centers. Catheterized urine specimens were collected and the microbiota was characterized by 16S rRNA gene sequencing. Patients were segregated into two groups according to each clinical parameter and differences in urinary microbiota diversity and composition were evaluated.

RESULTS

Higher prostate weight and prostate-specific antigen (PSA) levels were associated with higher alpha diversity in the urinary microbiota of BPH patients. At the specific microbe level, we found that the greater the prostatic weight, the lower the relative abundance of Streptococcus, while the greater the PSA levels, the higher the abundance of Lactobacillus. Treatment with 5-α-reductase inhibitor was associated with overall urinary microbiota composition, in part due to a higher abundance of Corynebacterium and Anaerococcus in this group.

CONCLUSIONS

We demonstrated that the urinary microbiota of BPH patients is associated with clinicopathological features, paving the way for larger studies in which causality between urinary microbiota and BPH can be appropriately explored.

Sexual dimorphism in bladder cancer: a review of etiology, biology, diagnosis, and outcomes

Bladder carcinoma represents a prevalent malignancy, wherein the influence of sex extends across its incidence, biological attributes, and clinical outcomes. This scholarly exposition meticulously examines pertinent investigations, elucidating the nuanced impact of sex on bladder cancer, and posits cogent avenues for future research and intervention modalities. In the initial discourse, an exhaustive scrutiny is undertaken of the etiological underpinnings of bladder cancer, encompassing variables such as tobacco consumption, occupational exposures, and genetic aberrations. Subsequently, a comprehensive dissection unfolds, delving into the intricate biological disparities inherent in sex vis-à-vis the initiation and progression of bladder cancer. This analytical framework embraces multifaceted considerations, spanning sex hormones, sex chromosomal dynamics, metabolic enzymatic cascades, and the intricate interplay with the microbiome. Lastly, a synthesized exposition encapsulates the ramifications of gender differentials on the diagnostic and prognostic landscapes of bladder cancer, underscoring the imperative for intensified investigative endeavors directed towards elucidating gender-specific variances and the formulation of tailored therapeutic strategies.

Urine microbiome in individuals with an impaired immune system

With the advent of next generation sequencing, it is now appreciated that human urine is not sterile. Recent investigations of the urinary microbiome (urobiome) have provided insights into several urological diseases. Urobiome dysbiosis, defined as non-optimal urine microbiome composition, has been observed in many disorders; however, it is not clear whether this dysbiosis is the cause of urinary tract disorders or a consequence. In addition, immunologically altered disorders are associated with higher rates of urinary tract infections. These disorders include immunoproliferative and immunodeficiency diseases, cancer, and immunosuppressant therapy in transplant recipients. In this review, we examine the current state of knowledge of the urobiome in immunologically altered diseases, its composition and metabolomic consequences. We conclude that more data are required to describe the urobiome in immune altered states, knowledge that could facilitate understanding the role of the urobiome and its pathophysiological effects on urinary tract infections and other disorders of the urinary tract.

The role of gut microbiota in the occurrence and progression of non-alcoholic fatty liver disease

Background

Non-alcoholic fatty liver disease (NAFLD) is the most prevalent cause of chronic liver disease worldwide, and gut microbes are associated with the development and progression of NAFLD. Despite numerous studies exploring the changes in gut microbes associated with NAFLD, there was no consistent pattern of changes.

Method

We retrieved studies on the human fecal microbiota sequenced by 16S rRNA gene amplification associated with NAFLD from the NCBI database up to April 2023, and re-analyzed them using bioinformatic methods.

Results

We finally screened 12 relevant studies related to NAFLD, which included a total of 1,189 study subjects (NAFLD, n = 654; healthy control, n = 398; obesity, n = 137). Our results revealed a significant decrease in gut microbial diversity with the occurrence and progression of NAFLD (SMD = -0.32; 95% CI -0.42 to -0.21; p < 0.001). Alpha diversity and the increased abundance of several crucial genera, including Desulfovibrio, Negativibacillus, and Prevotella, can serve as an indication of their predictive risk ability for the occurrence and progression of NAFLD (all AUC > 0.7). The occurrence and progression of NAFLD are significantly associated with higher levels of LPS biosynthesis, tryptophan metabolism, glutathione metabolism, and lipid metabolism.

Conclusion

This study elucidated gut microbes relevance to disease development and identified potential risk-associated microbes and functional pathways associated with NAFLD occurrence and progression.

The Response of the Urinary Microbiome to Botox

INTRODUCTION AND HYPOTHESIS

Our objective was to evaluate if botox alters the urinary microbiome of patients with overactive bladder and whether this alteration is predictive of treatment response.

METHODS

This multicenter prospective cohort study included 18-89-year-old patients undergoing treatment for overactive bladder with 100 units of botox. Urine samples were collected by straight catheterization on the day of the procedure (S1) and again 4 weeks later (S2). Participants completed the Patient Global Impression of Improvement form at their second visit for dichotomization into responders and nonresponders. The microbiome was sequenced using 16s rRNA sequencing. Wilcoxon signed rank and Wilcoxon rank sum were used to compare the microbiome, whereas chi-square, Wilcoxon rank sum, and the independent t-test were utilized for clinical data.

RESULTS

Sixty-eight participants were included in the analysis. The mean relative abundance and prevalence of Beauveria bassiana, Xerocomus chrysenteron, Crinipellis zonata, and Micrococcus luteus were all found to increase between S1 and S2 in responders; whereas in nonresponders the mean relative abundance and prevalence of Pseudomonas fragi were found to decrease. The MRA and prevalence of Weissella cibaria, Acinetobacter johnsonii, and Acinetobacter schindleri were found to be greater in responders than nonresponders at the time of S1. Significant UM differences in the S1 of patients who did (n = 5) and did not go on to develop a post-treatment UTI were noted.

CONCLUSIONS

Longitudinal urobiome differences may exist between patients who do and do not respond to botox.

An emerging strategy: probiotics enhance the effectiveness of tumor immunotherapy via mediating the gut microbiome

The occurrence and progression of tumors are often accompanied by disruptions in the gut microbiota. Inversely, the impact of the gut microbiota on the initiation and progression of cancer is becoming increasingly evident, influencing the tumor microenvironment (TME) for both local and distant tumors. Moreover, it is even suggested to play a significant role in the process of tumor immunotherapy, contributing to high specificity in therapeutic outcomes and long-term effectiveness across various cancer types. Probiotics, with their generally positive influence on the gut microbiota, may serve as effective agents in synergizing cancer immunotherapy. They play a crucial role in activating the immune system to inhibit tumor growth. In summary, this comprehensive review aims to provide valuable insights into the dynamic interactions between probiotics, gut microbiota, and cancer. Furthermore, we highlight recent advances and mechanisms in using probiotics to improve the effectiveness of cancer immunotherapy. By understanding these complex relationships, we may unlock innovative approaches for cancer diagnosis and treatment while optimizing the effects of immunotherapy.

Does the urinary microbiome profile change after treatment of bladder cancer?

INTRODUCTION

We sought to investigate the change in the urinary microbiome profile after transurethral resection of bladder tumor (TURBT).

METHODS

Urine specimens were collected from consecutive patients with bladder cancer. Patients were divided into those with bladder tumors ("Tumor group": de novo tumors or recurrent/progressed after TURBT ± intravesical therapy) versus those without evidence of recurrence after treatment "No Recurrent Tumor group". Samples were analyzed using 16S rRNA sequencing. Alteration in the urinary microbiome was described in terms of alpha (diversity within a sample measured by Observed, Chao, Shannon, and Simpson indices), beta diversities (diversity among different samples measured by Brady Curtis Diversity index), and differential abundance of bacteria at the genus level. Analyses were adjusted for gender, method of preservation (frozen vs preservative), and method of collection (mid-stream vs. catheter).

RESULTS

Sixty-eight samples were analyzed (42 in "Tumor" vs 26 in "No Recurrent Tumor" groups). The median age was 70 years (IQR 64-74) and 85% were males. All patients in the "No Recurrent Tumor" group had non-muscle invasive bladder cancer and 85% received BCG compared to 69% and 43% for the "Tumor" group, respectively. There was no significant difference in alpha diversity (p > 0.05). Beta diversity was significantly different (p = 0.04). Veillonella and Bifidobacterium were more abundant in the "Tumor" group (> 2FC, p = 0.0002), while Escherichia-Shigella (> 2FC, p = 0.0002) and Helococcus (> 2FC, p = 0.0008) were more abundant in the "No Recurrent Tumor" group.

CONCLUSION

Bladder cancer patients with no recurrence and/or progression exhibited a different urinary microbiome profile compared to those with tumors.

The role of microbiota in tumorigenesis, progression and treatment of bladder cancer

For decades, the urinary system was regarded as a sterile environment due to the absence of any bacterial growth in clinical standard urine cultures from healthy individuals. However, a diverse array of microbes colonizes the urinary system in small quantities, exhibiting a variable compositional signature influenced by differences in sex, age, and pathological state. Increasing pieces of evidence suggest microbiota exists in tumor tissue and plays a crucial role in tumor microenvironment based on research in multiple cancer models. Current studies about microbiota and bladder cancer have preliminarily characterized the bladder cancer-related microbiota, but how the microbiota influences the biological behavior of bladder cancer remains unclarified. This review summarizes the characteristics of microbiota in bladder cancer, aims to propose possible mechanisms that microbiota acts in tumorigenesis and progression of bladder cancer based on advances in gut microbiota, and discusses the potential clinical application of microbiota in bladder cancer.

Is the Urinary and Gut Microbiome Associated With Bladder Cancer?

Background

Microbiome dysbiosis plays a role in the pathogenesis of many urological diseases, including bladder cancer (BC). The aim of the study was to compare the urinary and gut microbiota of patients with BC with a healthy control (HC) group.

Methods

The study group included patients hospitalized in 2020 to 2021 with diagnosed BC and HC. Prior to the transurethral resection of bladder tumor, patients collected their urine and stool which was then subjected to 16S rRNA gene sequencing.

Results

Overall, 25 patients were enrolled in the study: 18 in the BC group and 7 in the HC group. Analysis of the urine and stool microbiome showed no statistically significant differences between patients with BC and HC in alpha diversity, beta diversity, and difference in taxa relative abundance. Detailed analysis of urine and stool microbiome depending on patient- and tumor-related characteristics also showed no statistically significant differences in alpha diversity and beta diversity. Differences in abundance (ANCOM) were noted in both types of samples in patients with BC. In the urine test, genus Lactobacillus was more common in patients with a positive history of Bacillus Calmette-Guérin (BCG) therapy, while genus Howardella and the strain Streptococcus anginosus were more common in women. In stool samples, abundance of phylum Desulfobacterota was most abundant in Grade G1 and least in G2. Class Alphaproteobacteria, order Rhodospirillales, order Flavobacteriales, and family Flavobacteriaceae were more common in women.

Conclusions

The microbiome of urine and stool of patients with BC does not differ significantly from that of HC; however, its composition in patients with BC varies according to the patient's sex.

From mucosal infection to successful cancer immunotherapy

The clinical management of advanced malignancies of the upper and lower urinary tract has been revolutionized with the advent of immune checkpoint blockers (ICBs). ICBs reinstate or bolster pre-existing immune responses while creating new T cell specificities. Immunogenic cancers, which tend to benefit more from immunotherapy than cold tumours, harbour tumour-specific neoantigens, often associated with a high tumour mutational burden, as well as CD8+ T cell infiltrates and ectopic lymphoid structures. The identification of beneficial non-self tumour antigens and natural adjuvants is the focus of current investigation. Moreover, growing evidence suggests that urinary or intestinal commensals, BCG and uropathogenic Escherichia coli influence long-term responses in patients with kidney or bladder cancer treated with ICBs. Bacteria infecting urothelium could be a prominent target for T follicular helper cells and B cells, linking innate and cognate CD8+ memory responses. In the urinary tract, commensal flora differ between healthy and tumoural mucosae. Although antibiotics can affect the prognosis of urinary tract malignancies, bacteria can have a major influence on cancer immunosurveillance. Beyond their role as biomarkers, immune responses against uropathogenic commensals could be harnessed for the design of future immunoadjuvants that can be advantageously combined with ICBs.

Urinary Microbiome in Bladder Diseases-Review

The microbiome is the totality of microorganisms found in a specific biological niche. It has been proven that in the human body, the microbiome is responsible for its proper functioning. Dysbiosis, i.e., a disturbance in the composition of the microbiome, may be associated with the pathogenesis of many human diseases. Until recently, studies did not focus on the microbiome of the urinary tract, because, since the 19th century, there had been a dogma that urine in healthy people is sterile. Yet, advances in molecular biology techniques have allowed this dogma to be overthrown. The use of DNA sequencing has shown that the urinary tract has its own endogenous microbiome. This discovery enabled further research on the characteristics of the urine microbiomes of healthy people, as well as on the role of the urine microbiome in the pathogenesis of many urological diseases, including bladder diseases. The aim of this review is to summarize the current knowledge on the urinary microbiome in bladder diseases and to identify potential directions for further research.

Exploring the role of natural bioactive molecules in genitourinary cancers: how far has research progressed?

The primary approaches to treat cancerous diseases include drug treatment, surgical procedures, biotherapy, and radiation therapy. Chemotherapy has been the primary treatment for cancer for a long time, but its main drawback is that it kills cancerous cells along with healthy ones, leading to deadly adverse health effects. However, genitourinary cancer has become a concern in recent years as it is more common in middle-aged people. So, researchers are trying to find possible therapeutic options from natural small molecules due to the many drawbacks associated with chemotherapy and other radiation-based therapies. Plenty of research was conducted regarding genitourinary cancer to determine the promising role of natural small molecules. So, this review focused on natural small molecules along with their potential therapeutic targets in the case of genitourinary cancers such as prostate cancer, renal cancer, bladder cancer, testicular cancer, and so on. Also, this review states some ongoing or completed clinical evidence in this regard.

Using the Multidimensional Health Locus of Control Scale Form C to Investigate Health Beliefs About Bladder Cancer Prevention and Treatment Among Male Patients: Cross-Sectional Study

BACKGROUND

Bladder cancer is a leading cause of death among Chinese male populations in recent years. The health locus of control construct can mediate health status and outcomes, and it has proven helpful in predicting and explaining specific health-related behaviors. However, it has never been used to investigate health beliefs about bladder cancer prevention and treatment.

OBJECTIVE

This study aimed to classify male patients into different latent groups according to their beliefs about bladder cancer prevention and treatment and to identify associated factors to provide implications for the delivery of tailored education and interventions and the administration of targeted prevention and treatment.

METHODS

First, we designed a four-section questionnaire to solicit data: section 1-age, gender, and education; section 2-the communicative subscale of the All Aspects of Health Literacy Scale; section 3-the eHealth Literacy Scale; and section 4-health beliefs about bladder cancer prevention and treatment measured by the Multidimensional Health Locus of Control Scale Form C. We hypothesized that the participants' health beliefs about bladder cancer prevention and treatment measured in section 4 could be closely associated with information collected through sections 1 to 3. We recruited 718 Chinese male patients from Qilu Hospital of Shandong University, China, and invited them to participate in a web-based questionnaire survey. Finally, we used latent class analysis to identify subgroups of men based on their categorical responses to the items on the Multidimensional Health Locus of Control Scale Form C and ascertained factors contributing to the low self-efficacy group identified.

RESULTS

We identified 2 subgroups defined as low and moderate self-efficacy groups representing 75.8% (544/718) and 24.2% (174/718) of the total sample, respectively. Men in the low self-efficacy cluster (cluster 1: 544/718, 75.8%) were less likely to believe in their own capability or doctors' advice to achieve optimal outcomes in bladder cancer prevention and treatment. Men in the moderate self-efficacy cluster (cluster 2: 174/718, 24.2%) had distinct psychological traits. They had stronger beliefs in their own capability to manage their health with regard to bladder cancer prevention and treatment and moderate to high levels of trust in health and medical professionals and their advice to achieve better prevention and treatment outcomes. Four factors contributing to low self-efficacy were identified, including limited education (Year 6 to Year 12), aged ≥44 years, limited communicative health literacy, and limited digital health literacy.

CONCLUSIONS

This was the first study investigating beliefs about bladder cancer prevention and treatment among Chinese male patients. Given that bladder cancer represents a leading cause of death among Chinese male populations in recent years, the low self-efficacy cluster and associated contributing factors identified in this study can provide implications for clinical practice, health education, medical research, and health policy-making.

Epidemiology of Bladder Cancer in 2023: A Systematic Review of Risk Factors

CONTEXT

Bladder cancer (BC) is common worldwide and poses a significant public health challenge. External risk factors and the wider exposome (totality of exposure from external and internal factors) contribute significantly to the development of BC. Therefore, establishing a clear understanding of these risk factors is the key to prevention.

OBJECTIVE

To perform an up-to-date systematic review of BC's epidemiology and external risk factors.

EVIDENCE ACQUISITION

Two reviewers (I.J. and S.O.) performed a systematic review using PubMed and Embase in January 2022 and updated it in September 2022. The search was restricted to 4 yr since our previous review in 2018.

EVIDENCE SYNTHESIS

Our search identified 5177 articles and a total of 349 full-text manuscripts. GLOBOCAN data from 2020 revealed an incidence of 573 000 new BC cases and 213 000 deaths worldwide in 2020. The 5-yr prevalence worldwide in 2020 was 1 721 000. Tobacco smoking and occupational exposures (aromatic amines and polycyclic aromatic hydrocarbons) are the most substantial risk factors. In addition, correlative evidence exists for several risk factors, including specific dietary factors, imbalanced microbiome, gene-environment risk factor interactions, diesel exhaust emission exposure, and pelvic radiotherapy.

CONCLUSIONS

We present a contemporary overview of the epidemiology of BC and the current evidence for BC risk factors. Smoking and specific occupational exposures are the most established risk factors. There is emerging evidence for specific dietary factors, imbalanced microbiome, gene-external risk factor interactions, diesel exhaust emission exposure, and pelvic radiotherapy. Further high-quality evidence is required to confirm initial findings and further understand cancer prevention.

PATIENT SUMMARY

Bladder cancer is common, and the most substantial risk factors are smoking and workplace exposure to suspected carcinogens. On-going research to identify avoidable risk factors could reduce the number of people who get bladder cancer.

Identification of Potential Key Genes Linked to Gender Differences in Bladder Cancer Based on Gene Expression Omnibus (GEO) Database

Background

Growing evidence strongly indicates pivotal roles of gender differences in the occurrence and survival rate of patients with bladder cancer, with a higher incidence in males and poorer prognosis in females. Nevertheless, the molecular basis underlying gender-specific differences in bladder cancer remains unknown. The current study has tried to detect key genes contributing to gender differences in bladder cancer patients.

Materials and Methods

The gene expression profile of GSE13507 was firstly obtained from the Gene Expression Omnibus (GEO) database. Further, differentially expressed genes (DEGs) were screened between males and females using R software. Protein-protein interactive (PPI) network analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG), Gene Ontology (GO), and Kaplan-Meier survival analyses were also performed.

Results

We detected six hub genes contributing to gender differences in bladder cancer patients, containing IGF2, CCL5, ASPM, CDC20, BUB1B, and CCNB1. Our analyses demonstrated that CCNB1 and BUB1B were upregulated in tumor tissues of female subjects with bladder cancer. Other genes, such as IGF2 and CCL5, were associated with a poor outcome in male patients with bladder cancer. Additionally, three signaling pathways (focal adhesion, rheumatoid arthritis, and human T-cell leukemia virus infection) were identified to be differentially downregulated in bladder cancer versus normal samples in both genders.

Conclusion

Our findings suggested that gender differences may modulate the expression of key genes that contributed to bladder cancer occurrence and prognosis.

The bladder microbiome of NMIBC and MIBC patients revealed by 2bRAD-M

Background

Bladder cancer (BCa) is the most common malignancy of the urinary tract which can be divided into non-muscle-invasive bladder cancer (NMIBC) and muscle-invasive bladder cancer (MIBC), and their microbial differences are not fully understood. This study was conducted by performing 2bRAD sequencing for Microbiome (2bRAD-M) on NMIBC and MIBC tissue samples to investigate the microbiota differences between NMIBC and MIBC individuals.

Methods

A total of 22 patients with BCa, including 7 NMIBC and 15 MIBC, were recruited. Tumor tissues were surgically removed as samples and DNA was extracted. Type IIB restriction endonucleases were used to enzymatically cleave the microbial genome for each microbe's tag and map it to species-specific 2bRAD markers to enable qualitative and quantitative studies of microbes between MIBC and NMIBC tissues.

Results

A total of 527 species were detected. The microbial diversity of NMIBC tissues was significantly higher than that of MIBC tissues. Microbial composition of the two tumor tissues was similar, where Ralstonia_sp000620465 was the most dominant species. 4 species (Acinetobacter_guillouiae, Anoxybacillus_A_rupiensis, Brevibacillus_agri and Staphylococcus_lugdunensis) were enriched in NMIBC, while Ralstonia_mannitolilytica, Ralstonia_pickettii, and Ralstonia_sp000620465 were overrepresented in MIBC. 252 discriminatory character taxa were also revealed by linear discriminant analysis effect sizea (LEfSe). Species importance point plots identified Ralstonia_sp000620465, Cutibacterium_acnes and Ralstonia_pickettii as the three most important species between the two groups. Meanwhile, functional annotation analysis showed 3011 different COGs and 344 related signaling pathways between MIBC and NMIBC microbiome.

Conclusion

This first 2bRAD-M microbiome study on MIBC and NMIBC tissues revealed significant differences in the microbial environment between the two groups, which implies a potential association between tumor microbial dysbiosis and BCa, and provides a possible target and basis for subsequent studies on the mechanisms of BCa development and progression.

Building a nomogram plot based on the nanopore targeted sequencing for predicting urinary tract pathogens and differentiating from colonizing bacteria

Background

The identification of uropathogens (UPBs) and urinary tract colonizing bacteria (UCB) conduces to guide the antimicrobial therapy to reduce resistant bacterial strains and study urinary microbiota. This study established a nomogram based on the nanopore-targeted sequencing (NTS) and other infectious risk factors to distinguish UPB from UCB.

Methods

Basic information, medical history, and multiple urine test results were continuously collected and analyzed by least absolute shrinkage and selection operator (LASSO) regression, and multivariate logistic regression was used to determine the independent predictors and construct nomogram. Receiver operating characteristics, area under the curve, decision curve analysis, and calibration curves were used to evaluate the performance of the nomogram.

Results

In this study, the UPB detected by NTS accounted for 74.1% (401/541) of all urinary tract microorganisms. The distribution of ln(reads) between UPB and UCB groups showed significant difference (OR = 1.39; 95% CI, 1.246-1.551, p < 0.001); the reads number in NTS reports could be used for the preliminary determination of UPB (AUC=0.668) with corresponding cutoff values being 7.042. Regression analysis was performed to determine independent predictors and construct a nomogram, with variables ranked by importance as ln(reads) and the number of microbial species in the urinary tract of NTS, urine culture, age, urological neoplasms, nitrite, and glycosuria. The calibration curve showed an agreement between the predicted and observed probabilities of the nomogram. The decision curve analysis represented that the nomogram would benefit clinical interventions. The performance of nomogram with ln(reads) (AUC = 0.767; 95% CI, 0.726-0.807) was significantly better (Z = 2.304, p-value = 0.021) than that without ln(reads) (AUC = 0.727; 95% CI, 0.681-0.772). The rate of UPB identification of nomogram was significantly higher than that of ln(reads) only (χ^2 = 7.36, p-value = 0.009).

Conclusions

NTS is conducive to distinguish uropathogens from colonizing bacteria, and the nomogram based on NTS and multiple independent predictors has better prediction performance of uropathogens.

Recent development of urinary biomarkers for bladder cancer diagnosis and monitoring

Urine‐based liquid biopsy has emerged as a non‐invasive and effective tool for early screening and diagnosis of bladder cancer. This review provides a comprehensive overview of the current urine‐based biomarkers and methods for the detection and monitoring of bladder cancer. We focus on biomarkers including tumour DNAs, proteins, microbiome, tumour RNAs, long non‐coding RNAs, transfer RNA‐derived fragments, messenger RNAs, microRNAs, circular RNAs, exosomes and extrachromosomal circular DNA.

The Urinary Microbiome and Bladder Cancer

Bladder cancer is the 10th most common cancer worldwide. Approximately 75% of patients with bladder cancer will present with non-muscle invasive disease. Patients are usually treated with transurethral resection of bladder tumor (TURBT), in addition to adjuvant intravesical therapy (chemotherapy or anti-cancer immunotherapy with Bacillus Calmette Guerin- BCG) for those at intermediate-risk and high-risk of recurrence and progression. For many years, urine has been thought to be “sterile”; however, advanced microbiological and molecular techniques, including 16S ribosomal RNA (16S rRNA) sequencing, have negated that previous paradigm and confirmed the presence of a urinary microbiome. The urinary microbiome has been associated with several urological diseases, including interstitial cystitis, urgency urinary incontinence, neurogenic bladder dysfunction, and others. More recently, many reports are emerging about the role of the urinary microbiome in urothelial carcinogenesis, including gender disparity in bladder cancer and responses to treatments. The urinary microbiome may serve as a biomarker that can help with risk stratification as well as prediction of the response to intravesical therapies. However, the microbiome literature has been hampered by the lack of a unified standardized methodology for sample collection, type, preservation, processing, as well as bioinformatics analysis. Herein we describe and critique the literature on the association between urinary microbiome and bladder cancer and highlight some of the future directions.

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.

Bladder cancer is associated with decreased urinary microbiota diversity and alterations in microbial community composition

INTRODUCTION

Human urine microbiota (UM) research has uncovered associations between composition of microbial communities of the lower urinary tract and various disease states including several reports on the putative link between UM and bladder cancer (BC). The aim of this study was to investigate male UM in patients with BC and controls using catheterised urine specimens unlike in previous studies.

METHODS

Urine samples were obtained in theatre after surgical prepping and draping using aseptic catheterisation. DNA was extracted and hypervariable region V4 of the 16S rRNA gene was amplified using 515F and 806R primers. Sequencing was performed on Illumina MiSeq platform. Sequencing data were processed using appropriate software tools. Alpha diversity measures were calculated and compared between groups. Prevalence Interval for Microbiome Evaluation was used to test differences in beta diversity.

RESULTS

A total of 63 samples were included in the analysis. Mean age of study subjects was 65.1 years (SD 12.5). Thirty-four men had bladder cancer and 29 participants were undergoing interventions for benign conditions (benign prostate hyperplasia or upper urinary tract stone disease). BC patients had lower UM richness and diversity than controls (83 vs. 139 operational taxonomic units, P = 0.015; Shannon index: 2.46 vs. 2.94, P = 0.049). There were specific taxa enriched in cancer (Veillonella, Varibaculum, Methylobacterium-Methylorubrum) and control groups (Pasteurella, Corynebacterium, Acinetobacter), respectively.

CONCLUSION

BC patients had lower bladder microbiota richness and diversity than controls. Specific genera were enriched in cancer and control groups, respectively. These results corroborate some of previous reports while contradicting others. Future microbiota research would benefit from parallel transcriptomic/metabolomic analysis.

Urinary Eubacterium sp. CAG:581 Promotes Non-Muscle Invasive Bladder Cancer (NMIBC) Development through the ECM1/MMP9 Pathway

BACKGROUND

Increasing evidence points to the urinary microbiota as a possible key susceptibility factor for early-stage bladder cancer (BCa) progression. However, the interpretation of its underlying mechanism is often insufficient, given that various environmental conditions have affected the composition of urinary microbiota. Herein, we sought to rule out confounding factors and clarify how urinary Eubacterium sp. CAG:581 promoted non-muscle invasive bladder cancer (NMIBC) development.

METHODS

Differentially abundant urinary microbiota of 51 NMIBC patients and 47 healthy controls (as Cohort 1) were first determined by metagenomics analysis. Then, we modeled the coculture of NMIBC organoids with candidate urinary Eubacterium sp. CAG:581 in anaerobic conditions and explored differentially expressed genes of these NMIBC tissues by RNA-Seq. Furthermore, we dissected the mechanisms involved into Eubacterium sp. CAG:581 by inducing extracellular matrix protein 1 (ECM1) and matrix metalloproteinase 9 (MMP9) upregulation. Finally, we used multivariate Cox modeling to investigate the clinical relevance of urinary Eubacterium sp. CAG:581 16S ribosomal RNA (16SrRNA) levels to the prognosis of 406 NMIBC patients (as Cohort 2).

RESULTS

Eubacterium sp. CAG:581 infection accelerated the proliferation of NMIBC organoids (p < 0.01); ECM1 and MMP9 were the most upregulated genes induced by the increased colony forming units (CFU) gradient of Eubacterium sp. CAG:581 infection via phosphorylating ERK1/2 in NMIBC organoids of Cohort 1. Excluding the favorable impact of potential contributing factors, the ROC curve of Cohort 2 manifested its 3-year AUC value as 0.79 and the cut-off point of Eubacterium sp. CAG:581 16SrRNA as 10.3 (delta CT value).

CONCLUSION

Our evidence suggests that urinary Eubacterium sp. CAG:581 promoted NMIBC progression through the ECM1/MMP9 pathway, which may serve as the promising noninvasive diagnostic biomarker for NMIBC.