The Microbiome of the Prostate Tumor Microenvironment

Friends close, enemies closer: the complex role of the microbiome in antitumor immunity

Immunotherapy has achieved remarkable advances in cancer treatment by harnessing the immune system to combat tumors, yet its effectiveness remains inconsistent across patients and tumor types. The microbiota, a diverse assemblage of microorganisms residing at host barrier surfaces, is pivotal in shaping immune responses. This review explores the direct and indirect mechanisms via which the microbiota modulates antitumor immune responses both locally within the tumor microenvironment and systemically by affecting distant tumors. We discuss recent findings linking microbiota-derived metabolites and microbiota-derived antigens with antitumor immunity and immunotherapy response. Additionally, we discuss recent advances in microbiome-based therapies, including fecal microbiota transplantation. We propose the use and development of new analytical techniques to further characterize the complex functions and interactions between the microbiome and immune system. To conclude, we outline recommendations for future research and therapeutic approaches to leverage the microbiome to improve current immunotherapies.

Emerging roles of intratumoral microbiota: a key to novel cancer therapies

Microorganisms, including bacteria, viruses, and fungi, have been found to play critical roles in tumor microenvironments. Due to their low biomass and other obstacles, the presence of intratumor microbes has been challenging to definitively establish. However, advances in biotechnology have enabled researchers to reveal the association between intratumor microbiota and cancer. Recent studies have shown that tumor tissues, once thought to be sterile, actually contain various microorganisms. Disrupted mucosal barriers and adjacent normal tissues are important sources of intratumor microbiota. Additionally, microbes can invade tumors by traveling through the bloodstream to the tumor site and infiltrating through damaged blood vessels. These intratumor microbiota may promote the initiation and progression of cancers by inducing genomic instability and mutations, affecting epigenetic modifications, activating oncogenic pathways, and promoting inflammatory responses. This review summarizes the latest advancements in this field, including techniques and methods for identifying and culturing intratumor microbiota, their potential sources, functions, and roles in the efficacy of immunotherapy. It explores the relationship between gut microbiota and intratumor microbiota in cancer patients, and whether altering gut microbiota might influence the characteristics of intratumor microbiota and the host immune microenvironment. Additionally, the review discusses the prospects and limitations of utilizing intratumor microbiota in antitumor immunotherapy.

NK Cell-Microbiota Interaction Biomarker Strategy: Advancing Prostate Cancer Management

The role of natural killer (NK) cells in the management of prostate cancer (PCa) remains incompletely understood. Some have proposed that measuring NK cells in blood samples could serve as a reliable, minimally invasive tool for screening, assessing treatment effects, and predicting survival outcomes in PCa patients. However, the significance of different NK cell phenotypes remains unclear. Given the interplay between NK cells and the microbiome, we hypothesize that a combined signature of NK cell phenotypes derived from blood, along with microbiome profiles from oral, urine, and stool samples, could serve as a surrogate marker for NK cell activity in tumor and its microenvironment. Such an approach provides a practical alternative to invasive tumor biopsies by enabling the indirect assessment of NK cell function in tumors. Additionally, profiling NK cell phenotypes and their interactions with the microbiota has the potential to enhance prognostic accuracy and guide the development of personalized therapeutic strategies. Prospective studies are needed to validate the utility of NK cell and microbiome assays in personalized PCa management, with a focus on minimally invasive procedures and predictive signatures for treatment outcomes.

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.

The Urogenital System Microbiota: Is It a New Gamechanger in Urogenital Cancers?

The human microbiome, which encompasses microbial communities and their genetic material, significantly influences health and disease, including cancer. The urogenital microbiota, naturally present in the urinary and genital tracts, interact with factors such as age, lifestyle, and health conditions to affect homeostasis and carcinogenesis. Studies suggest that alterations in this microbiota contribute to the development and progression of genitourinary cancers, emphasizing the concept of oncobiome, which refers to microbial genetic contributions to cancer. Similarly, gut microbiota can influence hormone levels and systemic inflammation, impacting cancers such as cervical and prostate cancer. Advanced studies indicate that microbial communities in genitourinary cancers have distinct profiles that may serve as diagnostic biomarkers or therapeutic targets. Dysbiosis of the urinary microbiota correlates with bladder and kidney cancer. Additionally, gut microbiota influence the effectiveness of cancer treatments. However, further research is necessary to clarify causality, the role of microbial metabolites, and hormonal regulation. The aim of this review is to understand that these dynamics present opportunities for innovative cancer diagnostics and therapies, highlighting the need for integration of microbiology, oncology, and genomics to explore the role of microbiota in genitourinary cancers. For this, a comprehensive search of relevant databases was conducted, applying specific inclusion and exclusion criteria to identify studies examining the association between microbiota and urogenital cancers. Research into the mechanisms by which microbiota influence urogenital cancers may pave the way for new diagnostic and therapeutic approaches, ultimately improving patient outcomes.

Role of Microbiota-Derived Metabolites in Prostate Cancer Inflammation and Progression

Prostate cancer (PCa) is the most commonly detected malignancy in men worldwide. PCa is a slow-growing cancer with the absence of symptoms at early stages. The pathogenesis has not been entirely understood including the key risk factors related to PCa development like diet and microbiota derived metabolites. Microbiota may influence the host's immunological responses, inflammatory responses, and metabolic pathways, which may be crucial for the development and metastasis. Similarly, short-chain fatty acids, methylamines, hippurate, bile acids, and other metabolites generated by microbiota may have potential roles in cancer inflammation and progression of cancer. Most studies have focused on the role of metabolites and their pathways involved in chronic inflammation, tumor initiation, proliferation, and progression. In summary, the review discusses the role of microbiota and microbial-derived metabolite-built strategies in inflammation and progression of the PCa.

Comprehensive analysis of the interaction microbiome and prostate cancer: an initial exploration from multi-cohort metagenome and GWAS studies

INTRODUCTION

Prostate cancer is one of the most common cancers in the United States with a high mortality rate. In recent years, the traditional opinion about prostate microbiome was challenged. Although there still are some arguments, an escalating number of researchers are shifting their focus toward the microbiome within the prostate tumor environment.

METHODS

We mined the data of the microbiome extracted from the metagenome, and it offers a broader taxonomic coverage and accurate functional profiling. We used Kraken2, a mapping tool, to mine the gut microbiota of prostate cancer patients. A two-sample Mendelian Randomization was conducted to reflect the association between gut microbiome and cancer.

RESULTS

In the study, we found the consistency of the special intratumor microbiome of both non-metastatic tumors and metastatic tumors. And we dig the gut microbiome in patients with different treatments. We found that some microbiotas may be associated with prostate cancer progression and a special microbiome in metastatic prostate cancer may exist. The anti-androgen therapy can significantly change both the intratumor and gut microbiome.

CONCLUSION

With the progression and metastasis of prostate cancer, some intratumor microbiome changes. And anti-androgen influences both the intratumor and gut microbiome. Our discovery may help researchers further understand the progression, metastasis, and resistance of prostate cancer from the perspective of microbiome level.

Unveiling the hidden causal links: skin flora and cutaneous melanoma

Objective

The presence of skin flora (SF) has been identified as a significant factor in the onset and progression of cutaneous melanoma (CM). However, the vast diversity and abundance of SF present challenges to fully understanding the causal relationship between SF and CM.

Methods

A Two Sample Mendelian Randomization (TSMR) analysis was conducted to investigating the causal relationship between SF and CM. The Inverse-Variance Weighted (IVW) method was utilized as the primary approach to assess the causal relationship under investigation. Furthermore, an independent external cohort was employed to validate the initial findings, followed by a meta-analysis of the consolidated results. To address potential confounding factors related to the influence of SF on CM, a Multivariate Mendelian Randomization (MVMR) analysis was also conducted. Finally, a Reverse Mendelian Randomization (RMR) was conducted to further validate the causal association.

Results

TSMR results showed that 9 SF have a causal relationship with CM in the training cohort. Although these 9 SF weren't confirmed in the testing cohort, 4 SF remained significant in the meta-analysis after integrating results from both cohorts. MVMR analysis indicated that 3 SF were still significantly associated with CM after accounting for the interactions between different SF in the training cohort. No reverse causal relationship was identified in RMR analysis.

Conclusion

A total of 9 SF were identified as having a potential causal relationship with CM; however, a large randomized controlled trial is needed to verify these results.

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.

Investigating the role of the intratumoral microbiome in thyroid cancer development and progression

The intratumoral microbiome (ITM) is in the spotlight due to its possible contribution to the initiation, progression, and invasion of a wide range of cancers. Its precise contribution to cancer tumorigenesis is still elusive, though. Thyroid cancer(TC), the ninth leading cause of cancer globally and the most prevalent endocrine malignancy with a rapidly rising incidence among all cancers, has attracted much attention nowadays. Still, the association between the tumor's microbiome and TC progression and development is an evolving area of investigation with significant consequences for disease understanding and intervention. Therefore, this review offers an appropriate perspective on this emerging concept in TC based on prior studies on the ITM among the most common tumors worldwide, concentrating on TC. Moreover, information on the origin of the ITM and practical methods can pave the way for researchers to opt for the most appropriate method for further investigations on the ITM more accurately.

The bacterial microbiome and cancer: development, diagnosis, treatment, and future directions

The term "microbiome" refers to the collection of bacterial species that reside in the human body's tissues. Sometimes, it is used to refer to all microbial entities (bacteria, viruses, fungi, and others) which colonize the human body. It is now generally acknowledged that the microbiome plays a critical role in the host's physiological processes and general well-being. Changes in the structure and/or function of the microbiome (dysbiosis) are linked to the development of many diseases including cancer. The claim that because of their negatively charged membrane, cancer cells are more vulnerable to some bacteria than normal cells and that is how the link between these bacteria and cancer evolved has been refuted. Furthermore, the relationship between the microbiome and cancer is more evident in the emerging field of cancer immunotherapy. In this narrative review, we detailed the correlation between the presence/absence of specific bacterial species and the development, diagnosis, prognosis, and treatment of some types of cancer including colorectal, lung, breast, and prostate cancer. In addition, we discussed the mechanisms of microbiome-cancer interactions including genotoxin production, the role of free radicals, modification of signaling pathways in host cells, immune modulation, and modulation of drug metabolism by microbiome. Future directions and clinical application of microbiome in the early detection, prognosis, and treatment of cancer emphasizing on the role of fecal transplantation, probiotics, prebiotics, and microbiome biomarkers were also considered.

The Equilibrium of Bacterial Microecosystem: Probiotics, Pathogenic Bacteria, and Natural Antimicrobial Substances in Semen

Semen is a complex fluid that contains spermatozoa and also functions as a dynamic bacterial microecosystem, comprising probiotics, pathogenic bacteria, and natural antimicrobial substances. Probiotic bacteria, such as Lactobacillus and Bifidobacterium, along with pathogenic bacteria like Pseudomonas aeruginosa and Escherichia coli, play significant roles in semen preservation and reproductive health. Studies have explored the impact of pathogenic bacteria on sperm quality, providing insights into the bacterial populations in mammalian semen and their influence on sperm function. These reviews highlight the delicate balance between beneficial and harmful bacteria, alongside the role of natural antimicrobial substances that help maintain this equilibrium. Moreover, we discuss the presence and roles of antimicrobial substances in semen, such as lysozyme, secretory leukocyte peptidase inhibitors, lactoferrin, and antimicrobial peptides, as well as emerging antibacterial substances like amyloid proteins. Understanding the interactions among probiotics, pathogens, and antimicrobial agents is crucial for elucidating semen preservation and fertility mechanisms. Additionally, the potential for adding probiotic bacteria with recombinant antibacterial properties presents a promising avenue for the development of new semen extenders. This review offers updated insights to understand the equilibrium of the bacterial microecosystem in semen and points toward innovative approaches for improving semen preservation.

Integrated analysis of microbiome and metabolome reveals signatures in PDAC tumorigenesis and prognosis

Pancreatic cancer, predominantly pancreatic ductal adenocarcinoma (PDAC), is one of the most malignant tumors of the digestive system. Emerging evidence suggests the involvement of the microbiome and metabolic substances in the development of PDAC, yet the results remain contradictory. This study aims to identify the alterations and relationships in intratumoral microbiome and metabolites in PDAC. We collected matched tumor and normal adjacent tissue (NAT) samples from 105 PDAC patients and performed a 6-year follow-up. 2bRAD-M sequencing, untargeted liquid chromatography-tandem mass spectrometry, and untargeted gas chromatography-mass spectrometry were performed. Compared with NATs, microbial α-diversity decreased in PDAC tumors. The relative abundance of Staphylococcus aureus, Cutibacterium acnes, and Cutibacterium granulosum was higher in PDAC tumor after adjusting for confounding factors body mass index and M stage, and the presence of Ralstonia pickettii_B was found associated with a worse overall survival. Metabolomic analysis revealed distinctive differences in composition between PDAC and NAT, with 553 discriminative metabolites identified. Differential metabolites were revealed to originate from the microbiota and showed significant interactions with shifted bacterial species through KO (KEGG Orthology) genes. These findings suggest that the PDAC microenvironment harbors unique microbial-derived enzymatic reactions, potentially influencing the occurrence and development of PDAC by modulating the levels of glycerol-3-phosphate, succinate, carbonate, and beta-alanine.

IMPORTANCE

We conducted a large sample-size pancreatic adenocarcinoma microbiome study using a novel microbiome sequencing method and two metabolomic assays. Two significant outcomes of our analysis are: (i) commensal opportunistic pathogens Staphylococcus aureus, Cutibacterium acnes, and Cutibacterium granulosum were enriched in pancreatic ductal adenocarcinoma (PDAC) tumors compared with normal adjacent tissues, and (ii) worse overall survival was found related to the presence of Ralstonia pickettii_B. Microbial species affect the tumorigenesis, metastasis, and prognosis of PDAC via unique microbe-enzyme-metabolite interaction. Thus, our study highlights the need for further investigation of the potential associations between pancreatic microbiota-derived omics signatures, which may drive the clinical transformation of microbiome-derived strategies toward therapy-targeted bacteria.

Crosstalk Between the Intratumoral Microbiota and the Tumor Microenvironment: New Frontiers in Solid Tumor Progression and Treatment

BACKGROUND

The microbiota plays a significant role in the tumor microenvironment, and its impact on tumor development and treatment outcome cannot be overlooked. Thus, it is essential to comprehend the interactions between the microbiota and the tumor microenvironment.

RECENT FINDINGS

With the advent of next-generation sequencing, microbiota research has advanced significantly in recent years. The interaction between the intratumoral microbiota and the tumor microenvironment is an emerging area of research that holds great promise for understanding and treating solid tumor progression. This crosstalk between the intratumoral microbiota and the tumor microenvironment is a complex process that involves a multitude of factors, including the immune system, cellular signaling pathways, and metabolic processes. The origin of the intratumoral microbiota differs between various solid tumor, and the quantity and diversity of intratumoral microbiota also fluctuate significantly within each solid tumor.

CONCLUSION

The aim of this review is to provide a detailed summary of the intratumoral microbiota in various types of solid tumors. This will include an analysis of their origins, differences, and how they impact the progression of solid tumors. Furthermore, we will emphasize the significant potential that the intratumoral microbiota holds for the diagnosis and treatment of solid tumors.

The elusive male microbiome: revealing the link between the genital microbiota and fertility. Critical review and future perspectives

There is a growing focus on understanding the role of the male microbiome in fertility issues. Although research on the bacterial communities within the male reproductive system is in its initial phases, recent discoveries highlight notable variations in the microbiome's composition and abundance across distinct anatomical regions like the skin, foreskin, urethra, and coronary sulcus. To assess the relationship between male genitourinary microbiome and reproduction, we queried various databases, including MEDLINE (available via PubMed), SCOPUS, and Web of Science to obtain evidence-based data. The literature search was conducted using the following terms "gut/intestines microbiome," "genitourinary system microbiome," "microbiome and female/male infertility," "external genital tract microbiome," "internal genital tract microbiome," and "semen microbiome." Fifty-one relevant papers were analyzed, and eleven were strictly semen quality or male fertility related. The male microbiome, especially in the accessory glands like the prostate, seminal vesicles, and bulbourethral glands, has garnered significant interest because of its potential link to male fertility and reproduction. Studies have also found differences in bacterial diversity present in the testicular tissue of normozoospermic men compared to azoospermic suggesting a possible role of bacterial dysbiosis and reproduction. Correlation between the bacterial taxa in the genital microbiota of sexual partners has also been found, and sexual activity can influence the composition of the urogenital microbiota. Exploring the microbial world within the male reproductive system and its influence on fertility opens doors to developing ways to prevent, diagnose, and treat infertility. The present work emphasizes the importance of using consistent methods, conducting long-term studies, and deepening our understanding of how the reproductive tract microbiome works. This helps make research comparable, pinpoint potential interventions, and smoothly apply microbiome insights to real-world clinical practices.

Causal relationship between 150 skin microbiomes and prostate cancer: insights from bidirectional mendelian randomization and meta-analysis

Background

Despite relevant research, the relationship between skin microbiomes and prostate cancer remains controversial. This study utilizes bidirectional Mendelian randomization (MR) analysis combined with meta-analysis to explore the potential link between the two.

Objective

This study aims to identify the causal relationship between 150 skin microbiomes and prostate cancer (PCa) using bidirectional Mendelian randomization (MR) and meta-analysis.

Methods

This study employed a comprehensive Bidirectional Two-sample MR analysis using publicly available genetic data to ascertain the relationship between 150 skin microbiomes and PCa. We conducted extensive sensitivity analyses, tests for heterogeneity, and assessments of horizontal pleiotropy to ensure the accuracy of our results. Subsequently, we conducted a meta-analysis to strengthen our conclusions' robustness further. Finally, we performed reverse causal verification on the positive skin microbiomes and PCa.

Results

After conducting a meta-analysis and multiple corrections of the MR analysis results, our findings reveal a correlation between Neisseria in dry skin and PCa risk, identifying it as a risk factor. The IVW result shows an Odds Ratio (OR) of 1.009 (95% Confidence Interval [CI]: 1.004-1.014, P = 0.027). Furthermore, the reverse MR analysis indicates the absence of an inverse causal relationship between the two. Apart from the identified skin microbiome, no significant associations were found between the other microbiomes and PCa.

Conclusions

The study identified a correlation between Neisseria in dry skin, one of the 150 skin microbiomes, and the risk of developing PCa, establishing it as a risk factor for increased susceptibility to PCa.

A prospective evaluation of the prostate microbiome in malignant and benign tissue using transperineal biopsy

BACKGROUND

The link between the prostate microbiome and prostate cancer remains unclear. Few studies have analyzed the microbiota of prostate tissue, and these have been limited by potential contamination by transrectal biopsy. Transperineal prostate biopsy offers an alternative and avoids fecal cross-contamination. We aim to characterize the prostate microbiome using transperineal biopsy.

METHODS

Patients with clinical suspicion for prostate cancer who were to undergo transperineal prostate biopsy with magnetic resonance imaging (MRI) fusion guidance were prospectively enrolled from 2022 to 2023. Patients were excluded if they had Prostate Imaging Reporting and Data System lesions with scores ≤ 3, a history of prostate biopsy within 1 year, a history of prostate cancer, or antibiotic use within 30 days of biopsy. Tissue was collected from the MRI target lesions and nonneoplastic transitional zone. Bacteria were identified using 16S ribosomal RNA gene sequencing.

RESULTS

Across the 42 patients, 76% were found to have prostate cancer. Beta diversity indices differed significantly between the perineum, voided urine, and prostate tissue. There were no beta diversity differences between cancerous or benign tissue, or between pre- and postbiopsy urines. There appear to be unique genera more abundant in cancerous versus benign tissue. There were no differences in alpha diversity indices relative to clinical findings including cancer status, grade, and risk group.

CONCLUSIONS

We demonstrate a rigorous method to better characterize the prostate microbiome using transperineal biopsy and to limit contamination. These findings provide a framework for future large-scale studies of the microbiome of prostate cancer.

Microbiome-Stealth Regulator of Breast Homeostasis and Cancer Metastasis

Cumulative evidence attests to the essential roles of commensal microbes in the physiology of hosts. Although the microbiome has been a major research subject since the time of Luis Pasteur and William Russell over 140 years ago, recent findings that certain intracellular bacteria contribute to the pathophysiology of healthy vs. diseased tissues have brought the field of the microbiome to a new era of investigation. Particularly, in the field of breast cancer research, breast-tumor-resident bacteria are now deemed to be essential players in tumor initiation and progression. This is a resurrection of Russel's bacterial cause of cancer theory, which was in fact abandoned over 100 years ago. This review will introduce some of the recent findings that exemplify the roles of breast-tumor-resident microbes in breast carcinogenesis and metastasis and provide mechanistic explanations for these phenomena. Such information would be able to justify the utility of breast-tumor-resident microbes as biomarkers for disease progression and therapeutic targets.

Influence of diabetes on microbiome in prostate tissues of patients with prostate cancer

Background

Although microbiota in prostatic tissues of patients with prostate cancer have been studied, results of different studies have been inconsistent. Different ethnicity of study subjects, different study designs, and potential contaminations during sample collection and experiments might have influenced microbiome results of prostatic tissues. In this study, we analyzed microbiota and their potential functions in benign and malignant tissues of prostate cancer considering possible contaminants and host variables.

Materials and methods

A total of 118 tissue samples (59 benign tissues and 59 malignant tissues) obtained by robot-assisted laparoscopic radical prostatectomy were analyzed and 64 negative controls (from sampling to sequencing processes) were included to reduce potential contaminants.

Results

Alteration of the microbiome in prostate tissues was detected only in patients with diabetes. Furthermore, the influence of diabetes on microbiome was significant in malignant tissues. The microbiome in malignant tissues of patients with diabetes was influenced by pathologic stages. The relative abundance of Cutibacterium was reduced in the high pathologic group compared to that in the intermediate group. This reduction was related to microbial pathways increased in the high pathologic group.

Conclusion

Results of this study indicate that diabetes can influence the progression of prostate cancer with microbiome alteration in prostate tissues. Although further studies are necessary to confirm findings of this study, this study can help us understand tissue microbiome in prostate cancer and improve clinical therapy strategies.

Different Prostatic Tissue Microbiomes between High- and Low-Grade Prostate Cancer Pathogenesis

Numerous human pathologies, such as neoplasia, are related to particular bacteria and changes in microbiome constituents. To investigate the association between an imbalance of bacteria and prostate carcinoma, the microbiome and gene functionality from tissues of patients with high-grade prostate tumor (HGT) and low-grade prostate tumor (LGT) were compared utilizing next-generation sequencing (NGS) technology. The results showed abnormalities in the bacterial profiles between the HGT and LGT specimens, indicating alterations in the make-up of bacterial populations and gene functionalities. The HGT specimens showed higher frequencies of Cutibacterium, Pelomonas, and Corynebacterium genera than the LGT specimens. Cell proliferation and cytokine assays also showed a significant proliferation of prostate cancer cells and elevated cytokine levels in the cells treated with Cutibacterium, respectively, supporting earlier findings. In summary, the HGT and LGT specimens showed differences in bacterial populations, suggesting that different bacterial populations might characterize high-grade and low-grade prostate malignancies.

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.

Effects of low-intensity pulsed ultrasound on the microorganisms of expressed prostatic secretion in patients with IIIB prostatitis

To detect and analyze the changes of microorganisms in expressed prostatic secretion (EPS) of patients with IIIB prostatitis before and after low-intensity pulsed ultrasound (LIPUS) treatment, and to explore the mechanism of LIPUS in the treatment of chronic prostatitis (CP). 25 patients (study power was estimated using a Dirichlet-multinomial approach and reached 96.5% at α = 0.05 using a sample size of 25) with IIIB prostatitis who were effective in LIPUS treatment were divided into two groups before and after LIPUS treatment. High throughput second-generation sequencing technique was used to detect and analyze the relative abundance of bacterial 16 s ribosomal variable regions in EPS before and after treatment. The data were analyzed by bioinformatics software and database, and differences with P < 0.05 were considered statistically significant. Beta diversity analysis showed that there was a significant difference between groups (P = 0.046). LEfSe detected four kinds of characteristic microorganisms in the EPS of patients with IIIB prostatitis before and after LIPUS treatment. After multiple comparisons among groups by DESeq2 method, six different microorganisms were found. LIPUS may improve patients' clinical symptoms by changing the flora structure of EPS, stabilizing and affecting resident bacteria or opportunistic pathogens.

The microbiota continuum along the upper reproductive tract of male rat and its relation to semen parameters

Given the physiological function and anatomical location of the reproductive tract, studying the upper reproductive tract microbiota may be essential for studying male infertility and other male diseases. This study aimed to characterize the microbiota of the upper reproductive tract male rats and investigate whether specific microbial compositions are associated with sperm parameters. 16S rRNA gene sequencing was used to characterize the microbial composition in the testis, epididymis, seminal vesicles, vas deferens and prostate tissues of the rats. The results showed significant enrichment of Methyloperoxococcus spp. in testicular tissues, Jeotgalicoccus spp. in epididymal tissues. Spearman's correlation analysis revealed that the abundance of several bacterial genera in epididymal, testicular, and seminal vesicle gland tissues correlated with several sperm activity parameters. Our findings provide detailed information on characterizing the upper reproductive tract microbiome in male rats, as well as a potentially crucial link between the reproductive system microbiota and sperm quality.

Current Trends and Challenges of Microbiome Research in Prostate Cancer

PURPOSE OF REVIEW

The role of the gut microbiome in prostate cancer is an emerging area of research interest. However, no single causative organism has yet been identified. The goal of this paper is to examine the role of the microbiome in prostate cancer and summarize the challenges relating to methodology in specimen collection, sequencing technology, and interpretation of results.

RECENT FINDINGS

Significant heterogeneity still exists in methodology for stool sampling/storage, preservative options, DNA extraction, and sequencing database selection/in silico processing. Debate persists over primer choice in amplicon sequencing as well as optimal methods for data normalization. Statistical methods for longitudinal microbiome analysis continue to undergo refinement. While standardization of methodology may help yield more consistent results for organism identification in prostate cancer, this is a difficult task due to considerable procedural variation at each step in the process. Further reproducibility and methodology research is required.

Prostate Tissue Microbiome in Patients with Prostate Cancer: A Systematic Review

Some researchers have speculated that the prostatic microbiome is involved in the development of prostate cancer (PCa) but there is no consensus on certain microbiota in the prostatic tissue of PCa vs. healthy controls. This systematic review aims to investigate and compare the microbiome of PCa and healthy tissue to determine the microbial association with the pathogenesis of PCa. We searched MEDLINE, Embase, and Scopus databases. Articles were screened by two independent and blinded reviewers. Literature that compared the prostatic tissue microbiome of patients with PCa with benign controls was included. We found that PCa may be associated with increased Propionibacterium acnes, the herpesviridae and papillomaviridae families, and Mycoplasma genitalium, but definitive conclusions cannot be drawn from the existing data. Challenges include the difficulty of obtaining uncontaminated tissue samples and securing tissue from healthy controls. As a result, methods are varied with many studies using cancerous and "healthy" tissue from the same prostate. The organisms chosen for each study were also highly variable, making it difficult to compare studies. These issues have led to lower confidence in our results. Overall, further work is warranted to better understand the implications of the prostatic microbiome in the pathogenesis of PCa.

The emerging tumor microbe microenvironment: From delineation to multidisciplinary approach-based interventions

Intratumoral microbiota has become research hotspots, and emerges as a non-negligent new component of tumor microenvironments (TME), due to its powerful influence on tumor initiation, metastasis, immunosurveillance and prognosis despite in low-biomass. The accumulations of microbes, and their related components and metabolites within tumor tissues, endow TME with additional pluralistic features which are distinct from the conventional one. Therefore, it's definitely necessary to comprehensively delineate the sophisticated landscapes of tumor microbe microenvironment, as well as their functions and related underlying mechanisms. Herein, in this review, we focused on the fields of tumor microbe microenvironment, including the heterogeneity of intratumor microbiota in different types of tumors, the controversial roles of intratumoral microbiota, the basic features of tumor microbe microenvironment (i.e., pathogen-associated molecular patterns (PAMPs), typical microbial metabolites, autophagy, inflammation, multi-faceted immunomodulation and chemoresistance), as well as the multidisciplinary approach-based intervention of tumor microbiome for cancer therapy by applying wild-type or engineered live microbes, microbiota metabolites, antibiotics, synthetic biology and rationally designed biomaterials. We hope our work will provide valuable insight to deeply understand the interplay of cancer-immune-microbial, and facilitate the development of microbes-based tumor-specific treatments.

The reproductive microbiome in dogs: Friend or foe?

The microbiome of the reproductive tract is an area of research in full development. Specifically, the microbiome may be involved in reproductive health, disease, and pregnancy outcomes, as has been shown in humans and animals, including dogs. The aim of the present review was to summarize current knowledge on the microbiome of the canine reproductive tract, to expose the controversial role that some bacterial agents may play in canine subfertility, and to highlight future research perspectives. This review discussed whether the use of antimicrobials in dogs is appropriate to increase reproductive performance and to treat subfertility without proper diagnosis, and the possible use of probiotics to modulate the reproductive canine microbiome. Finally, we indicate areas in which scientific knowledge is currently lacking, and could be promising directions for future research.

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.

The potential role of the microbiota in prostate cancer pathogenesis and treatment

The human body hosts a complex and dynamic population of trillions of microorganisms - the microbiota - which influences the body in homeostasis and disease, including cancer. Several epidemiological studies have associated specific urinary and gut microbial species with increased risk of prostate cancer; however, causal mechanistic data remain elusive. Studies have associated bacterial generation of genotoxins with the occurrence of TMPRSS2-ERG gene fusions, a common, early oncogenic event during prostate carcinogenesis. A subsequent study demonstrated the role of the gut microbiota in prostate cancer endocrine resistance, which occurs, at least partially, through the generation of androgenic steroids fuelling oncogenic signalling via the androgen receptor. These studies present mechanistic evidence of how the host microbiota might be implicated in prostate carcinogenesis and tumour progression. Importantly, these findings also reveal potential avenues for the detection and treatment of prostate cancer through the profiling and modulation of the host microbiota. The latter could involve approaches such as the use of faecal microbiota transplantation, prebiotics, probiotics, postbiotics or antibiotics, which can be used independently or combined with existing treatments to reverse therapeutic resistance and improve clinical outcomes in patients with prostate cancer.

The Influence of the Microbiome on Urological Malignancies: A Systematic Review

The microbiome, once considered peripheral, is emerging as a relevant player in the intricate web of factors contributing to cancer development and progression. These often overlooked microorganisms, in the context of urological malignancies, have been investigated primarily focusing on the gut microbiome, while exploration of urogenital microorganisms remains limited. Considering this, our systematic review delves into the complex role of these understudied actors in various neoplastic conditions, including prostate, bladder, kidney, penile, and testicular cancers. Our analysis found a total of 37 studies (prostate cancer 12, bladder cancer 20, kidney cancer 4, penile/testicular cancer 1), revealing distinct associations specific to each condition and hinting at potential therapeutic avenues and future biomarker discoveries. It becomes evident that further research is imperative to unravel the complexities of this domain and provide a more comprehensive understanding.

Emerging Relationship between the Gut Microbiome and Prostate Cancer

The human gut microbiota changes under the influence of environmental and genetic factors, affecting human health. Extensive studies have revealed that the gut microbiome is closely associated with many non-intestinal diseases. Among these, the influence of the gut microbiome on cancer biology and the efficacy of cancer therapy has attracted much attention. Prostate cancer cells are affected by direct contact with the microbiota of local tissues and urine, and a relationship between prostate cancer cells and the gut microbiota has been suggested. In the human gut microbiota, bacterial composition differs depending on prostate cancer characteristics, such as histological grade and castration resistance. Moreover, the involvement of several intestinal bacteria in testosterone metabolism has been demonstrated, suggesting that they may affect prostate cancer progression and treatment through this mechanism. Basic research indicates that the gut microbiome also plays an important role in the underlying biology of prostate cancer through multiple mechanisms owing to the activity of microbial-derived metabolites and components. In this review, we describe the evidence surrounding the emerging relationship between the gut microbiome and prostate cancer, termed the "gut-prostate axis."

Bacteria in cancer initiation, promotion and progression

Cancer cells originate from a series of acquired genetic mutations that can drive their uncontrolled cell proliferation and immune evasion. Environmental factors, including the microorganisms that colonize the human body, can shift the metabolism, growth pattern and function of neoplastic cells and shape the tumour microenvironment. Dysbiosis of the gut microbiome is now recognized as a hallmark of cancer by the scientific community. However, only a few microorganisms have been identified that directly initiate tumorigenesis or skew the immune system to generate a tumour-permissive milieu. Over the past two decades, research on the human microbiome and its functionalities within and across individuals has revealed microbiota-focused strategies for health and disease. Here, we review the evolving understanding of the mechanisms by which the microbiota acts in cancer initiation, promotion and progression. We explore the roles of bacteria in gastrointestinal tract malignancies and cancers of the lung, breast and prostate. Finally, we discuss the promises and limitations of targeting or harnessing bacteria in personalized cancer prevention, diagnostics and treatment.

Dissecting Microbiome-Derived SCFAs in Prostate Cancer: Analyzing Gut Microbiota, Racial Disparities, and Epigenetic Mechanisms

Prostate cancer (PCa) continues to be the most diagnosed cancer and the second primary cause of fatalities in men globally. There is an abundance of scientific evidence suggesting that the human microbiome, together with its metabolites, plays a crucial role in carcinogenesis and has a significant impact on the efficacy of anticancer interventions in solid and hematological cancers. These anticancer interventions include chemotherapy, immune checkpoint inhibitors, and targeted therapies. Furthermore, the microbiome can influence systemic and local immune responses using numerous metabolites such as short-chain fatty acids (SCFAs). Despite the lack of scientific data in terms of the role of SCFAs in PCa pathogenesis, recent studies show that SCFAs have a profound impact on PCa progression. Several studies have reported racial/ethnic disparities in terms of bacterial content in the gut microbiome and SCFA composition. These studies explored microbiome and SCFA racial/ethnic disparities in cancers such as colorectal, colon, cervical, breast, and endometrial cancer. Notably, there are currently no published studies exploring microbiome/SCFA composition racial disparities and their role in PCa carcinogenesis. This review discusses the potential role of the microbiome in PCa development and progression. The involvement of microbiome-derived SCFAs in facilitating PCa carcinogenesis and their effect on PCa therapeutic response, particularly immunotherapy, are discussed. Racial/ethnic differences in microbiome composition and SCFA content in various cancers are also discussed. Lastly, the effects of SCFAs on PCa progression via epigenetic modifications is also discussed.

Is type III prostatitis also associated with bacterial infection?

Objective

To explore whether type III prostatitis is related to bacterial infection by detecting the composition and function of microorganisms in expressed prostatic secretion (EPS) of patients with chronic prostatitis (CP) and healthy people.

Methods

According to the inclusion and exclusion criteria, 57 subjects were included in our study, divided into the healthy group, type II prostatitis group, and type III prostatitis group. 16s rRNA sequencing technique was used to detect and analyze the microbial composition of EPS in each group. Additionally, the metagenomics sequencing technique was used to further explore the function of different bacteria in the type III prostatitis group. Data analysis was performed by bioinformatics software, and the results were statistically significant when P<0.05.

Results

Many microorganisms exist in EPS in both CP patients and healthy populations. However, the relative abundance of Pseudomonas, Haemophilus, Sneathia, Allobaculum, and Enterococcus in CP patients (including type II and III) were significantly different. Still, the relative abundance of different bacteria in type II prostatitis patients was much higher than in type III. The metagenomics sequencing results for the type III prostatitis group showed that the different bacteria had certain biological functions.

Conclusion

Based on our sequencing results and previous studies, we suggest that type III prostatitis may also be caused by bacterial infection.

Intratumoural microbiota: from theory to clinical application

Cancer is a major cause of high morbidity and mortality worldwide. Several environmental, genetic and lifestyle factors are associated with the development of cancer in humans and result in suboptimal treatment. The human microbiota has been implicated in the pathophysiological process of cancer and has been used as a diagnostic, prognostic and risk assessment tool in cancer management. Notably, both extratumoural and intratumoural microbiota are important components of the tumor microenvironment, subtly influencing tumorigenesis, progression, treatment and prognosis. The potential oncogenic mechanisms of action of the intratumoural microbiota include induction of DNA damage, influence on cell signaling pathways and impairment of immune responses. Some naturally occurring or genetically engineered microorganisms can specifically accumulate and replicate in tumors and then initiate various anti-tumor programs, ultimately promoting the therapeutic effect of tumor microbiota and reducing the toxic and side effects of conventional tumor treatments, which may be conducive to the pursuit of accurate cancer treatment. In this review, we summarise evidence revealing the impact of the intratumoural microbiota on cancer occurrence and progress and potential therapeutic and diagnostic applications, which may be a promising novel strategy to inhibit tumor development and enhance therapeutic efficacy. Video Abstract.

Biochemical Recurrence in Prostate Cancer Is Associated with the Composition of Lactobacillus: Microbiome Analysis of Prostatic Tissue

Many human pathologies, such as malignancy, are linked with specific bacteria and changes in the constituents of the microbiome. In order to examine the association between an imbalance of bacteria and prostate carcinoma, a comparison of the microbiomes present in patients with biochemical recurrence (BCR) or NO BCR (NBCR) was performed. Additionally, 16S rRNA-based next-generation sequencing was applied to identify the bacterial profiles within these tumors in terms of the bacteria and operational genes present. The percentage average taxonomic composition between the taxa indicated no difference between BCR and NBCR. In addition, alpha and beta diversity indices presented no distinction between the cohorts in any statistical method. However, taxonomic biomarker discovery indicated a relatively higher population of Lactobacillus in the NBCR group, and this finding was supported by PCR data. Along with that, differences in the operational activity of the bacterial genes were also determined. It is proposed that the biochemical recurrence was linked to the quantity of Lactobacillus present. The aim of this study was to investigate the microbiome involved in prostate carcinoma and the potential association between them.

The Molecular Basis and Clinical Consequences of Chronic Inflammation in Prostatic Diseases: Prostatitis, Benign Prostatic Hyperplasia, and Prostate Cancer

Chronic inflammation is now recognized as one of the major risk factors and molecular hallmarks of chronic prostatitis, benign prostatic hyperplasia (BPH), and prostate tumorigenesis. However, the molecular mechanisms by which chronic inflammation signaling contributes to the pathogenesis of these prostate diseases are poorly understood. Previous efforts to therapeutically target the upstream (e.g., TLRs and IL1-Rs) and downstream (e.g., NF-κB subunits and cytokines) inflammatory signaling molecules in people with these conditions have been clinically ambiguous and unsatisfactory, hence fostering the recent paradigm shift towards unraveling and understanding the functional roles and clinical significance of the novel and relatively underexplored inflammatory molecules and pathways that could become potential therapeutic targets in managing prostatic diseases. In this review article, we exclusively discuss the causal and molecular drivers of prostatitis, BPH, and prostate tumorigenesis, as well as the potential impacts of microbiome dysbiosis and chronic inflammation in promoting prostate pathologies. We specifically focus on the importance of some of the underexplored druggable inflammatory molecules, by discussing how their aberrant signaling could promote prostate cancer (PCa) stemness, neuroendocrine differentiation, castration resistance, metabolic reprogramming, and immunosuppression. The potential contribution of the IL1R-TLR-IRAK-NF-κBs signaling molecules and NLR/inflammasomes in prostate pathologies, as well as the prospective benefits of selectively targeting the midstream molecules in the various inflammatory cascades, are also discussed. Though this review concentrates more on PCa, we envision that the information could be applied to other prostate diseases. In conclusion, we have underlined the molecular mechanisms and signaling pathways that may need to be targeted and/or further investigated to better understand the association between chronic inflammation and prostate diseases.

Potential values of formalin-fixed paraffin-embedded tissues for intratumoral microbiome analysis in breast cancer

Breast cancer (BC) tissues have been proved to harbor microorganisms, which could potentially contribute to oncogenesis. Formalin-fixed paraffin-embedded (FFPE) tissues are the most widespread clinical samples in BC research. To verify the potential of FFPE tissues in microbiological analysis, we analyzed the microbial communities of FFPE and fresh frozen (FF) tumor samples from 30 participants diagnosed with BC deploying 16S rRNA sequencing. The operational taxonomic units (OTUs) analysis showed that 78.55% of OTUs in FFPE samples were consistent with FF samples. The composition of core bacteria did not change much, and there is also no difference in alpha diversity between FFPE and FF (without unclassified bacteria). Taxonomic variation results show that Firmicutes and Bacteroidota phyla, and their major classes, maintained the same proportion under two preservation methods. In addition, the major class Gammaproteobacteria, as well as its dominant orders Burkholderiales and Pseudomonadales all showed no significant difference in paired analysis. Moreover, the Proteobacteria and Actinobacteriota phyla showed no significant difference between FFPE and FF samples after subtracting unclassified bacteria. Therefore, premised with the intrinsic tumor heterogeneity and unclassified bacteria, there are potential values of FFPE tissues for intratumoral microbiome analysis in breast cancer.

Awareness of intratumoral bacteria and their potential application in cancer treatment

Hitherto, the recognition of the microbiota role in tumorigenesis and clinical studies mostly focused on the intestinal flora. In contrast to the gut microbiome, microorganisms resident in tumor tissue are in close contact with cancer cells and therefore have the potential to have similar or even different functional patterns to the gut flora. Some investigations have shown intratumoral bacteria, which might come from commensal microbiota in mucosal areas including the gastrointestinal tract and oral cavity, or from nearby normal tissues. The existence, origin, and interactions of intratumoral bacteria with the tumor microenvironment all contribute to intratumoral microorganism heterogeneity. Intratumoral bacteria have a significant role in tumor formation. They can contribute to cancer at the genetic level by secreting poisons that directly damage DNA and also intimately related to immune system response at the systemic level. Intratumoral bacteria have an impact on chemotherapy and immunotherapy in cancer. Importantly, various properties of bacteria such as targeting and ease of modification make them powerful candidates for precision therapy, and combining microbial therapies with other therapies is expected to improve the effectiveness of cancer treatment. In this review, we mainly described the heterogeneity and potential sources of intratumoral bacteria, overviewed the important mechanisms by which they were involved in tumor progression, and summarized their potential value in oncology therapy. At last, we highlight the problems of research in this field, and look forward to a new wave of studies using the various applications of intratumoral microorganisms in cancer therapy.

Investigating the oral microbiome in retrospective and prospective cases of prostate, colon, and breast cancer

The human microbiome has been proposed as a potentially useful biomarker for several cancers. To examine this, we made use of salivary samples from the Atlantic Partnership for Tomorrow's Health (PATH) project and Alberta's Tomorrow Project (ATP). Sample selection was divided into both a retrospective and prospective case control design examining prostate, breast, and colon cancer. In total 89 retrospective and 260 prospective cancer cases were matched to non-cancer controls and saliva samples were sequenced using 16S rRNA gene sequencing. We found no significant differences in alpha diversity. All beta diversity measures were insignificant except for unweighted UniFrac profiles in retrospective breast cancer cases and weighted UniFrac, Bray-Curtis and Robust Atchinson's distances in colon cancer after testing with age and sex adjusted MiRKAT models. Differential abundance (DA) analysis showed several taxa that were associated with previous cancer in all three groupings. Only one genus (Clostridia UCG-014) in breast cancer and one ASV (Fusobacterium periodonticum) in colon cancer was identified by more than one DA tool. In prospective cases three ASVs were associated with colon cancer, one ASV with breast cancer, and one ASV with prostate cancer. Random Forest classification showed low levels of signal in both study designs in breast and prostate cancer. Contrastingly, colon cancer did show signal in our retrospective analysis (AUC: 0.737) and in one of two prospective cohorts (AUC: 0.717). Our results indicate that it is unlikely that reliable microbial oral biomarkers for breast and prostate cancer exist.. However, further research into the oral microbiome and colon cancer could be fruitful.

Bacterial lipopolysaccharide-related genes are involved in the invasion and recurrence of prostate cancer and are related to immune escape based on bioinformatics analysis

Background

The composition of the tumor microbial microenvironment participates in the whole process of tumor disease. However, due to the limitations of the current technical level, the depth and breadth of the impact of microorganisms on tumors have not been fully recognized, especially in prostate cancer (PCa). Therefore, the purpose of this study is to explore the role and mechanism of the prostate microbiome in PCa based on bacterial lipopolysaccharide (LPS)-related genes by means of bioinformatics.

Methods

The Comparative Toxicogenomics Database (CTD) was used to find bacterial LPS- related genes. PCa expression profile data and clinical data were acquired from TCGA, GTEx, and GEO. The differentially expressed LPS-related hub genes (LRHG) were obtained by Venn diagram, and gene set enrichment analysis (GSEA) was used to investigate the putative molecular mechanism of LRHG. The immune infiltration score of malignancies was investigated using single-sample gene set enrichment analysis (ssGSEA). Using univariate and multivariate Cox regression analysis, a prognostic risk score model and nomogram were developed.

Results

6 LRHG were screened. LRHG were involved in functional phenotypes such as tumor invasion, fat metabolism, sex hormone response, DNA repair, apoptosis, and immunoregulation. And it can regulate the immune microenvironment in the tumor by influencing the antigen presentation of immune cells in the tumor. And a prognostic risk score and the nomogram, which were based on LRHG, showed that the low-risk score has a protective effect on patients.

Conclusion

Microorganisms in the PCa microenvironment may use complex mechanism and networks to regulate the occurrence and development of PCa. Bacterial lipopolysaccharide-related genes can help build a reliable prognostic model and predict progression-free survival in patients with prostate cancer.

Synergistic Target of Intratumoral Microbiome and Tumor by Metronidazole-Fluorouridine Nanoparticles

Clinical and experimental evidence confirmed bacterial infiltration in a variety of tumors, which is related to the progression and therapeutic effects of the tumors. Although the administration of antibiotics inhibits the growth of bacteria inside the tumor, systemic distribution of antibiotics induces an imbalance of other microbiomes in the body, which in turn leads to the development of new diseases. To address this clinical challenge, we nanonized an antibiotic in this study. Metronidazole, an antibiotic against broad anaerobes, was linked to fluorouridine to form an amphiphilic small molecule, metronidazole-fluorouridine, which further autoassembled as metronidazole-fluorouridine nanoparticles (MTI-FDU) in a hydrophilic solution. The disulfide bond in the linker cleaves in response to high levels of glutathione (GSH) in the tumor microenvironment. The synergistic antitumor effect of MTI-FDU was observed in two animal models of gut cancer with intratumoral bacteria. Analysis revealed that metronidazole delivered by nanoparticles attacked bacteria inside the tumor, while it had minimal effect on gut microbial homeostasis. Further experiments at the cellular and molecular levels disclosed that MTI-FDU shaped the tumor immune microenvironment through clearance of bacteria and bacterial products. In conclusion, we achieved a synergistic antitumor effect by a dual target of both the intratumoral microbiome and tumor cells. Antibiotic-composed nanoparticles have a clinical advantage in the treatment of tumors with bacteria infiltration, which kill pro-tumor bacteria efficiently as well as keep a balanced microbiota of the patient.

Human Male Genital Tract Microbiota

The human body is vastly colonised by microorganisms, whose impact on health is increasingly recognised. The human genital tract hosts a diverse microbiota, and an increasing number of studies on the male genital tract microbiota suggest that bacteria have a role in male infertility and pathological conditions, such as prostate cancer. Nevertheless, this research field remains understudied. The study of bacterial colonisation of the male genital tract is highly impacted by the invasive nature of sampling and the low abundance of the microbiota. Therefore, most studies relied on the analysis of semen microbiota to describe the colonisation of the male genital tract (MGT), which was thought to be sterile. The aim of this narrative review is to present the results of studies that used next-generation sequencing (NGS) to profile the bacterial colonisation patterns of different male genital tract anatomical compartments and critically highlight their findings and their weaknesses. Moreover, we identified potential research axes that may be crucial for our understanding of the male genital tract microbiota and its impact on male infertility and pathophysiology.

Vasectomy has No Impact on Future Lower Urinary Tract Symptoms Diagnoses: A Retrospective Cohort Claims Database Analysis

Purpose

The aim of this study was to assess whether there is an association between vasectomy and benign prostatic hyperplasia with associated lower urinary tract symptoms (BPH/LUTS) due to inflammatory etiology.

Materials and Methods

We assessed the incidence of BPH/LUTS in men who had undergone vasectomy in a matched cohort analysis using the TriNetX Research Network. We identified men aged 30 to 60 years who underwent vasectomy and had a follow-up visit within 6 months to 5 years after vasectomy from January 2010 through December 2022 and compared them with matched controls. Outcomes recorded include diagnoses of BPH (N40, N40.1), BPH-related medication prescriptions, and BPH-related procedures. We accounted for confounding variables through propensity score-matching for age; race; and history of comorbid medical conditions: hyperlipidemia (International Classification of Disease-10: E78), metabolic syndrome (E88.81), overweight or obesity (E66), testicular hypofunction (E29.1), hypertension (I10-I16), nicotine dependence (F17), and obstructive sleep apnea (G47.33).

Results

There was no significant difference in BPH diagnosis between postvasectomy men vs controls (0.84% vs 0.80%, RR: 0.95, 95% CI 0.86-1.05) or BPH/LUTS diagnosis (0.48% vs 0.44%, RR: 0.92, 95% CI 0.81-1.05) within 6 months to 5 years after vasectomy, respectively. No differences in BPH medication prescription (0.94% vs 0.84%) or rate of BPH procedures (0.022% vs 0.017%) were detected between the 2 groups.

Conclusions

This study suggests that vasectomy does not increase the risk of BPH development and/or LUTS worsening compared with the general population, providing assurance to both patients and health care providers who may consider vasectomy as a safe family planning option.

Potential links between the microbiota and T cell immunity determine the tumor cell fate

The central role of the microbiota as a pivotal factor regulating anti-tumor immune responses has recently been appreciated. Increasing evidence has put a spotlight on the connection of microbiota to T cells, by showing impaired effector and/or memory responses in germ-free (GF) mice or in the presence of dysbiotic communities, and association with tumor growth and overall survival (OS). These observations also have significant implications for anti-tumor therapy and vaccination, suggesting that the communication between T cells and the microbiota involves soluble mediators (microbiota-derived metabolites) that influence various functions of T cells. In addition, there is growing appreciation of the role of bacterial translocation into the peritumoral milieu from the intestinal tract, as well as of locally developed tumor microbial communities, spatially separated from the gut microbiota, in shaping the tumor microbiome. Collectively, these findings have added new support to the idea that tonic inputs mirroring the existence of tumor microbiome could regulate the function of tumor-infiltrating T cells and tissue-resident memory T (TRM) cells. In this review, we focus on recent advances and aspects of these active areas of investigation and provide a comprehensive overview of the unique mechanisms that play a pivotal role in the regulation of anti-tumor immunity by the microbiota, some of which could be of particular relevance for addressing problems caused by tumor heterogeneity. It is our hope that this review will provide a theoretical foundation for future investigations in this area.

Microbiota of Urine, Glans and Prostate Biopsies in Patients with Prostate Cancer Reveals a Dysbiosis in the Genitourinary System

Prostate cancer (PCa) is the most common malignant neoplasm with the highest worldwide incidence in men aged 50 years and older. Emerging evidence suggests that the microbial dysbiosis may promote chronic inflammation linked to the development of PCa. Therefore, this study aims to compare the microbiota composition and diversity in urine, glans swabs, and prostate biopsies between men with PCa and non-PCa men. Microbial communities profiling was assessed through 16S rRNA sequencing. The results indicated that α-diversity (number and abundance of genera) was lower in prostate and glans, and higher in urine from patients with PCa, compared to non-PCa patients. The different genera of the bacterial community found in urine was significantly different in PCa patients compared to non-PCa patients, but they did not differ in glans and prostate. Moreover, comparing the bacterial communities present in the three different samples, urine and glans show a similar genus composition. Linear discriminant analysis (LDA) effect size (LEfSe) analysis revealed significantly higher levels of the genera Streptococcus, Prevotella, Peptoniphilus, Negativicoccus, Actinomyces, Propionimicrobium, and Facklamia in urine of PCa patients, whereas Methylobacterium/Methylorubrum, Faecalibacterium, and Blautia were more abundant in the non-PCa patients. In glans, the genus Stenotrophomonas was enriched in PCa subjects, while Peptococcus was more abundant in non-PCa subjects. In prostate, Alishewanella, Paracoccus, Klebsiella, and Rothia were the overrepresented genera in the PCa group, while Actinomyces, Parabacteroides, Muribaculaceae sp., and Prevotella were overrepresented in the non-PCa group. These findings provide a strong background for the development of potential biomarkers with clinical interest.

Interaction between Host and Microbes in the Semen of Patients with Idiopathic Nonobstructive Azoospermia

Men with nonobstructive azoospermia (NOA) face the dual problems of low sperm count and low sperm quality. Most men with NOA without a clear cause are classified as having idiopathic NOA (iNOA). Previous studies found that microbes exist in semen, and the semen microbes of NOA men are different from those of normal men. However, the relevant mechanism is not clear. In this study, we answered the three questions of "who is there," "what is it doing," and "who is doing it" by combining 16s rRNA, nontargeted metabolome detection and metabolite traceability analysis. We found that the composition and interaction of seminal plasma microbes in the iNOA group changed. Metabolite traceability analysis and metabolic pathway analysis revealed that microbial abnormalities in the NOA group were closely related to the decrease of microbial degradation of toluene and the increase of metabolism of fructose or mannose. In addition, the metabolic relationship between microbes and the host in male semen in iNOA revealed that such microbes can produce harmful metabolites that affect sperm quality, the microbes compete with sperm for essential nutrients, and their presence reduces sperm production of essential nutrients. IMPORTANCE Idiopathic nonobstructive azoospermia is one of the great challenges in assisted reproductive therapy. Although microdissection testicular sperm extraction technology is currently available, many men with iNOA still face the problem of poor sperm retrieval and poor sperm quality. The role of seminal plasma microbes in male disease has been continuously investigated since semen was demonstrated to harbor commensal microbes. To our knowledge, this is the first detailed description of the microbe-host relationship in iNOA semen. This study is an important complement to research on the treatment and etiology of iNOA and the rationale for our ongoing research.

Bacteria and macrophages in the tumor microenvironment

Cancer and microbial infections are significant worldwide health challenges. Numerous studies have demonstrated that bacteria may contribute to the emergence of cancer. In this review, we assemble bacterial species discovered in various cancers to describe their variety and specificity. The relationship between bacteria and macrophages in cancer is also highlighted, and we look for ample proof to establish a biological basis for bacterial-induced macrophage polarization. Finally, we quickly go over the potential roles of metabolites, cytokines, and microRNAs in the regulation of the tumor microenvironment by bacterially activated macrophages. The complexity of bacteria and macrophages in cancer will be revealed as we gain a better understanding of their pathogenic mechanisms, which will lead to new therapeutic approaches for both inflammatory illnesses and cancer.

Mechanisms of Prostate Cancer Cells Survival and Their Therapeutic Targeting

Prostate cancer (PCa) is today the second most common cancer in the world, with almost 400,000 deaths annually. Multiple factors are involved in the etiology of PCa, such as older age, genetic mutations, ethnicity, diet, or inflammation. Modern treatment of PCa involves radical surgical treatment or radiation therapy in the stages when the tumor is limited to the prostate. When metastases develop, the standard procedure is androgen deprivation therapy, which aims to reduce the level of circulating testosterone, which is achieved by surgical or medical castration. However, when the level of testosterone decreases to the castration level, the tumor cells adapt to the new conditions through different mechanisms, which enable their unhindered growth and survival, despite the therapy. New knowledge about the biology of the so-called of castration-resistant PCa and the way it adapts to therapy will enable the development of new drugs, whose goal is to prolong the survival of patients with this stage of the disease, which will be discussed in this review.

Current understanding of the intratumoral microbiome in various tumors

It is estimated that in the future, the number of new cancer cases worldwide will exceed the 19.3 million recorded in 2020, and the number of deaths will exceed 10 million. Cancer remains the leading cause of human mortality and lagging socioeconomic development. Intratumoral microbes have been revealed to exist in many cancer types, including pancreatic, colorectal, liver, esophageal, breast, and lung cancers. Intratumoral microorganisms affect not only the host immune system, but also the effectiveness of tumor chemotherapy. This review concentrates on the characteristics and roles of intratumoral microbes in various tumors. In addition, the potential of therapies targeting intratumoral microbes, as well as the main challenges currently delaying these therapies, are explored. Furthermore, we briefly summarize existing technical methods used to characterize intratumoral microbes. We hope to provide ideas for exploring intratumoral microbes as potential biomarkers and targets for tumor diagnosis, treatment, and prognostication.