Stool Microbiome Signature Associated with Response to Neoadjuvant Pembrolizumab in Patients with Muscle-invasive Bladder Cancer

HEX-1 reduces colitis-driven colorectal cancer via inactivating the prolyl isomerase PIN1 sensitization and remodeling the gut microbiota

Metabolic reprogramming, a pivotal hallmark of cancer, plays a crucial role in both the initiation and progression of colorectal cancer (CRC). Despite the vast unknowns surrounding the identity and biological activities of most natural metabolites in diseases, our study, utilizing native metabolomics results through GC-MS/MS, identified a small molecule, 4,4-Dimethyl-2-cyclohexen-1-one, named HEX-1 in the serum of CRC patients. We have further explored and assessed its biological activities. HEX-1 suppressed the proliferation of cancer cells and tumorigenesis via the inactivation and sensitization of PIN1. Notably, HEX-1 exhibits similar functional effects as all-trans retinoic acid (atRA) but stands out by not inducing the degradation of PIN1 mRNA or protein expression, unlike biological compounds associated with atRA. HEX-1 demonstrated the ability to induce G1/S arrest in vitro and ameliorate the progression of inflammatory CRC in mice by remodeling the gut microbiota. As volatile organic compounds (VOCs), HEX-1 could be detected feasibly. Its unique ability to penetrate whole cell populations positions it as a promising approach for cancer therapy and as an enhancer for chemotherapy and immunotherapy. The findings suggest that HEX-1 holds the potential as a valuable addition to the armamentarium against CRC.

Anticancer Potential of Prebiotics: Targeting Estrogen Receptors and PI3K/AKT/mTOR in Breast Cancer

Estrogen receptors (ERs) play a critical role in breast cancer (BC) development and progression, with ERα being oncogenic and ERβ exhibiting tumor-suppressive properties. The interaction between ER signaling and other molecular pathways, such as PI3K/AKT/mTOR, influences tumor growth and endocrine resistance. Emerging research highlights the role of prebiotics in modulating gut microbiota, which may influence estrogen metabolism, immune function, and therapeutic responses in BC. This review explores the impact of prebiotics on estrogen receptor modulation, gut microbiota composition, immune regulation, and metabolic pathways in breast cancer. The potential of prebiotics as adjunctive therapies to enhance treatment efficacy and mitigate chemotherapy-related side effects is discussed. A comprehensive analysis of recent preclinical and clinical studies was conducted, examining the role of prebiotics in gut microbiota modulation, immune regulation, and metabolic reprogramming in breast cancer. The impact of short-chain fatty acids (SCFAs) derived from prebiotic fermentation on epigenetic regulation and endocrine resistance was also evaluated. Prebiotics were found to modulate the gut microbiota-estrogen axis, reduce inflammation, and influence immune responses. SCFAs demonstrated selective estrogen receptor downregulation and metabolic reprogramming, suppressing tumor growth. Synbiotic interventions mitigate chemotherapy-related side effects, improving the quality of life in breast cancer patients. Prebiotics offer a promising avenue for breast cancer prevention and therapy by modulating estrogen metabolism, immune function, and metabolic pathways. Future clinical trials are needed to validate their efficacy as adjunctive treatments in breast cancer management.

Microbiome landscapes of the bladder, intestine, and vagina in bladder cancer: a systematic review

BACKGROUND

Microbiomes have been linked to oncogenesis, e.g. the intestinal microbiome and colon cancer or HPV-associated cervical cancer. A connection between microbiomes of different body cavities and tumor oncogenesis was shown. The gut microbiome's influence on bladder cancer was established, raising the question whether nearby microbiomes (rectum, vagina) also influence bladder cancer due to their proximity.

OBJECTIVE

Considering the influence of various body cavities and the broader microbial components, this systematic review aims to investigate differences in the bladder, vaginal, and intestinal microbiota-including bacterial, viral, fungal and archaea-between patients with bladder cancer and healthy controls.

METHODS

Databases (PubMed, Scopus, Embase) were searched until April 2022. Three types of studies were included: "(1) studies using bladder cancer and control groups (case-controlled studies) (2) studies that provided information on the presence or abundance of microbial taxa (3) studies that provided information on increased or decreased taxa in bladder cancer and/or control groups.". Risk of bias was assessed using the Newcastle Ottawa Scale.

RESULTS

Fourteen studies (695 samples: 403 bladder cancer, 292 controls) were analyzed. Bacterial taxa that have been detected in at least two studies, the genera Geobacillus and Rubrobacter were more frequently in bladder cancer patients; while Streptococcus and Roseomonas were more prevalent in controls. No consistent taxa were identified across stool or bladder tissue samples.

CONCLUSION

The microbiota in bladder cancer patients show significant variation across studies. Standardized methods and expanded investigations into viral and fungal components are needed to clarify the role of microbiota in bladder cancer.

Understanding the microbiome as a mediator of bladder cancer progression and therapeutic response

Bladder cancer (BCa) remains a significant source of morbidity and mortality. BCa is one of the most expensive tumors to treat, in part because of a lack of nonsurgical options. The recent advent of immunotherapy, alone or in combination with other compounds, has improved therapeutic options. Resistance to immunotherapy remains common, and many patients do not have durable response. Recent advances indicate immunotherapy efficacy may be tied in part to the endogenous bacteria present in our body, more commonly referred to as the microbiome. Laboratory and clinical data now support the idea that a healthy microbiome is critical to effective response to immunotherapy. At the same time, pathogenic interactions between the microbiome and immune cells can also serve to drive formation of tumors, increasing the complexity of these interactions. Given the rising importance of immunotherapy in BCa, understanding how we might be able to alter the microbiome to improve therapeutic efficacy offers a novel route to improved patient care. The goal of this review is to examine our current understanding of microbial interactions with the immune system and cancer with an emphasis on BCa. We will further attempt to define both current gaps in knowledge and future directions that may yield beneficial results to the field.

Urine-Stable Aptamer-Conjugated Gold Nanorods for the Early Detection of High-Grade Bladder Cancer Residual Disease

The limitations of current diagnostic imaging techniques and therapies for bladder cancer are associated with and responsible for the recurrence and progression of residual disease, with an impact on social costs and quality of life of patients. This study delivers a cost-effective solution for the detection of bladder cancer residual disease, which is represented by the early detection of bladder cancer lesions < 1 mm. Urine-stable 34-mer SH-terminated 2'F-Py-RNA aptamer that recognizes the integrin α5β1, expressed by 81% of human high-grade non-muscle invasive bladder cancer, is developed. The intravesical instillation of aptamer-conjugated gold nanorods as contrast agent for photoacoustic imaging is validated in a preclinical model of orthotopic bladder cancer expressing the integrin α5β1. The photoacoustic signal of gold nanorods remains on the tumor surface for 3 h and allows early detection of cancer lesions < 1 mm. The aptamer is internalized into lysosomes, an opportunity that paves the way for lysosomal-mediated drug release in tumor cells. This study highlights the potential of urine-stable aptamer for the delivery of a solution to target the residual high-grade bladder cancer disease.

The Role of the Microbiome in Cancer Therapies: Current Evidence and Future Directions

The microbiome is essential for maintaining human health and is also a key factor in the development and progression of various diseases, including cancer. Growing evidence has highlighted the microbiome's significant impact on cancer development, progression, and treatment outcomes. As research continues to unfold, the microbiome and its modulation stand out as a promising frontier in cancer research and therapy. This review highlights current literature on the interplay between various cancer treatment modalities and human microbiotas, focusing on how the microbiome may affect treatment efficacy and toxicity and its potential as a therapeutic target to enhance future outcomes.

The role of the urinary microbiome in genitourinary cancers

Genitourinary cancers account for 20% of cancer instances globally and pose a substantial burden. The microbiome, defined as the ecosystem of organisms that reside within and on the human body, seems to be closely related to multiple cancers. Research on the gut microbiome has yielded substantial insights into the interactions of this entity with the immune system and cancer therapeutic efficacy, whereas the urinary microbiome has been relatively less well-studied. Advances in next-generation sequencing technologies led to new discoveries in the urinary microbiome, which might aid in early detection, risk stratification and personalized treatment strategies in genitourinary cancers. Mechanistic investigations have also suggested a role for the urinary microbiome in modulating the tumour microenvironment and host immune response. For example, distinct urinary microbial signatures have been linked to bladder cancer occurrence and recurrence risk, with specific taxa associated with cytokine production and inflammation. Urinary microbiome signatures have also been explored as potential biomarkers for non-invasive cancer detection. However, challenges remain in standardizing methodologies, validating findings across studies, and establishing causative mechanisms. As investigations into the urinary microbiome continue to evolve, so does the potential for developing microbiome-modulating therapies and enhancing diagnostic capabilities to improve outcomes in patients with genitourinary cancers.

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.

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.