The role of microbiota in the development of colorectal cancer

Metabolic interactions of host-gut microbiota: New possibilities for the precise diagnosis and therapeutic discovery of gastrointestinal cancer in the future-A review

Gastrointestinal (GI) cancer continues to pose a significant global health challenge. Recent advances in our understanding of the complex relationship between the host and gut microbiota have shed light on the critical role of metabolic interactions in the pathogenesis and progression of GI cancer. In this study, we examined how microbiota interact with the host to influence signalling pathways that impact the formation of GI tumours. Additionally, we investigated the potential therapeutic approach of manipulating GI microbiota for use in clinical settings. Revealing the complex molecular exchanges between the host and gut microbiota facilitates a deeper understanding of the underlying mechanisms that drive cancer development. Metabolic interactions hold promise for the identification of microbial signatures or metabolic pathways associated with specific stages of cancer. Hence, this study provides potential strategies for the diagnosis, treatment and management of GI cancers to improve patient outcomes.

Monoacylglycerol acyltransferase-2 inhibits colorectal carcinogenesis in APCmin+/- mice

Monoacylglycerol acyltransferase-2 (MOGAT2), encodes MOGAT enzyme in the re-synthesis of triacylglycerol and protects from metabolism disorders. While, its precise involvement in colorectal cancer (CRC) progression remains inadequately understood. Our study demonstrated that knockout of Mogat2 in Apcmin/+ mice expedited intestinal tumor growth and progression, indicating that Mogat2 plays a tumor-suppressing role in CRC. Mechanically, Mogat2 deletion resulted in a significant alter the gut microbiota, while Fecal Microbiota Transplantation (FMT) experiments demonstrated that the gut microbiota in Mogat2 deleted mice promoted tumor growth. Furthermore, we identified Mogat2 as a functional regulator suppressing CRC cell proliferation and tumor growth by inhibiting the NF-κB signaling pathway in vivo. Collectively, these results provide novel insights into the protective double roles of Mogat2, inhibiting of NF-κB pathway and keeping gut microbiota homeostasis in colorectal cancer, which may help the development of novel cancer treatments for CRC.

Host-diet-microbiota interplay in intestinal nutrition and health

The intestine is populated by a complex and dynamic assortment of microbes, collectively called gut microbiota, that interact with the host and contribute to its metabolism and physiology. Diet is considered a key regulator of intestinal microbiota, as ingested nutrients interact with and shape the resident microbiota composition. Furthermore, recent studies underscore the interplay of dietary and microbiota-derived nutrients, which directly impinge on intestinal stem cells regulating their turnover to ensure a healthy gut barrier. Although advanced sequencing methodologies have allowed the characterization of the human gut microbiome, mechanistic studies assessing diet-microbiota-host interactions depend on the use of genetically tractable models, such as Drosophila melanogaster. In this review, we first discuss the similarities between the human and fly intestines and then we focus on the effects of diet and microbiota on nutrient-sensing signaling cascades controlling intestinal stem cell self-renewal and differentiation, as well as disease. Finally, we underline the use of the Drosophila model in assessing the role of microbiota in gut-related pathologies and in understanding the mechanisms that mediate different whole-body manifestations of gut dysfunction.

Differential analysis of serum immunology and gut microbiota in patients with gastrointestinal diseases

Objective

Gastric and intestinal diseases possess distinct characteristics although they are interconnected. The primary objective of this study was to investigate the pathogenesis of gastrointestinal diseases through different analyses of clinical characteristics, serum immunology, and gut microbiota in patients with gastrointestinal diseases.

Methods

We collected serum samples from 89 patients with gastrointestinal diseases and 9 healthy controls for immunological assessment, stool samples for DNA extraction, library construction, sequencing, as well as clinical data for subsequent analysis.

Results

Regarding clinical characteristics, there were significant differences between the disease group and the healthy control (HC) group, particularly in terms of age, cancer antigen 125 (CA125), cancer antigen 199 (CA199), alpha-fetoprotein (AFP), total bilirubin (TBIL) and indirect bilirubin (IBIL). The intestinal disease (ID) group exhibited the highest IL-6 level, which significantly differed from the stomach disease (SD) group (p < 0.05). In comparing the HC with the ID groups, significant differences in abundance were detected across 46 species. The HC group displayed a greater abundance of Clostridiales, Clostridia, Firmicutes, Bifidobacterium, Bifidobacteriaceae, Bifidobacteriales, Actinobacteria, Veillonellaceae, Longum, Copri, Megamonas and Callidus than other species. Similarly, when comparing the HC with the SD groups, significant differences in abundance were identified among 49 species, with only one species that the Lachnospiraceae in the HC group exhibited a higher abundance than others. Furthermore, certain clinical characteristics, such as CA125, CA199, glucose (Glu), creatine kinase-MB (CKMB) and interleukin-22 (IL-22), displayed positive correlations with enriched gut species in the ID and SD groups, while exhibiting a negative correlation with the HC group.

Conclusion

The disturbance in human gut microbiota is intimately associated with the development and progression of gastrointestinal diseases. Moreover, the gut microbiota in the HC group was found more diverse than that in the ID and SD groups, and there were significant differences in microbial species among the three groups at different classification levels. Notably, a correlation was identified between specific clinical characteristics (e.g., CA125, CA199, Glu, CKMB and IL-22) and gut microbiota among patients with gastrointestinal diseases.

Microbiomes in pancreatic cancer can be an accomplice or a weapon

Recently, several investigations have linked the microbiome to pancreatic cancer progression. It is critical to reveal the role of different microbiomes in the occurrence, development, and treatment of pancreatic cancer. The current review summarizes the various microbiota types in pancreatic cancer while updating and supplementing the mechanisms of the representative gut, pancreatic, and oral microbiota, and their metabolites during its pathogenesis and therapeutic intervention. Several novel strategies have been introduced based on the tumor-associated microbiome to optimize the early diagnosis and prognosis of pancreatic cancer. The pros and cons involving different microbiomes in treating pancreatic cancer are discussed. The microbiome-related clinical trials for pancreatic cancer theranostics are outlined. This convergence of cutting-edge knowledge will provide feasible ideas for developing innovative therapies against pancreatic cancer.

Klebsiella aerogenes exacerbates colon tumorigenesis in the AOM/DSS-induced C57BL/6J mouse

Klebsiella aerogenes (K. aerogenes, KA) is a gram-negative opportunistic pathogen from the Klebsiella species and the Enterobacteriaceae family. However, the impact of K. aerogenes on colorectal cancer (CRC) remains uncertain. A colitis-associated tumorigenesis animal model was established by administering azoxymethane (AOM) and dextran sulfate sodium (DSS) to C57BL/6J mice. The concentration of K. aerogenes gavage in mice was 109 cfu. The study measured the following parameters: tumor formation (number and size), intestinal permeability (MUC2, ZO-1, and Occludin), colonic inflammation (TNF-α, IL-1β, IL-6, and IL-10), proliferation and the fluctuation of the intestinal flora. Under the AOM/DSS-treated setting, K. aerogenes colonization worsened colitis by exacerbating intestinal inflammatory reaction and destroying the mucosal barrier. The intervention markedly augmented the quantity and dimensions of neoplasm in the AOM/DSS mice, stimulated cellular growth, and impeded cellular programmed cell death. In addition, K. aerogenes exacerbated the imbalance of the intestinal microbiota by elevating the abundance of Pseudomonas, Erysipelatoclostridium, Turicibacter, Rikenella, and Muribaculum and leading to a reduction in the abundance of Odoribacter, Alloprevotella, Roseburia, and Lachnospiraceae_NK4A136_group. The presence of K. aerogenes in AOM/DSS-treated mice promoted tumorigenesis, worsened intestinal inflammation, disrupted the intestinal barrier, and caused disturbance to the gut microbiota.

Microbiota Implications in Endocrine-Related Diseases: From Development to Novel Therapeutic Approaches

This comprehensive review article delves into the critical role of the human microbiota in the development and management of endocrine-related diseases. We explore the complex interactions between the microbiota and the endocrine system, emphasizing the implications of microbiota dysbiosis for the onset and progression of various endocrine disorders. The review aims to synthesize current knowledge, highlighting recent advancements and the potential of novel therapeutic approaches targeting microbiota-endocrine interactions. Key topics include the impact of microbiota on hormone regulation, its role in endocrine pathologies, and the promising avenues of microbiota modulation through diet, probiotics, prebiotics, and fecal microbiota transplantation. We underscore the importance of this research in advancing personalized medicine, offering insights for more tailored and effective treatments for endocrine-related diseases.

Human Mycobiota and Its Role in Cancer Progression, Diagnostics and Therapeutics: A Link Lesser-Known

Although not as well studied as the bacterial component of the human microbiota, the commensal fungi or mycobiota play important roles in maintaining our health by augmenting our immune system. This mycobiota is also associated with various fatal diseases like opportunistic mycoses, and even cancer, with different cancers having respective type-specific mycobiota. The different fungal species which comprise these different intratumoral mycobiota play important roles in cancer progression. The aim of this review paper is to decipher the association between mycobiota and cancer, and shed light on new avenues in cancer diagnosis, and the development of new anti-cancer therapeutics.

The role of intestinal flora on tumorigenesis, progression, and the efficacy of PD-1/PD-L1 antibodies in colorectal cancer

Intestinal flora affects the maturation of the host immune system, serves as a biomarker and efficacy predictor in the immunotherapy of several cancers, and has an important role in the development of colorectal cancer (CRC). Anti-PD-1/PD-L1 antibodies have shown satisfactory results in MSI-H/dMMR CRC but performed poorly in patients with MSS/pMMR CRC. In recent years an increasing number of studies have shown that intestinal flora has an important impact on anti-PD-1/PD-L1 antibody efficacy in CRC patients. Preclinical and clinical evidence have suggested that anti-PD-1/PD-L1 antibody efficacy can be improved by altering the composition of the intestinal flora in CRC. Herein, we summarize the studies related to the influence of intestinal flora on anti-PD-1/PD-L1 antibody efficacy in CRC and discuss the potential underlying mechanism(s). We have focused on the impact of the intestinal flora on the efficacy and safety of anti-PD-1/PD-L1 antibodies in CRC and how to better utilize the intestinal flora as an adjuvant to improve the efficacy of anti-PD-1/PD-L1 antibodies. In addition, we have provided a basis for the potential of the intestinal flora as a new treatment modality and indicator for determining patient prognosis.

Diet-mediated gut microbial community modulation and signature metabolites as potential biomarkers for early diagnosis, prognosis, prevention and stage-specific treatment of colorectal cancer

BACKGROUND

Over the last decade, studies have shown an increased incidence of colorectal cancer (CRC), particularly early onset colorectal cancer (EOCRC). Researchers have demonstrated that dietary behavior, especially among young adults, influences alterations in the gut microbial community, leading to an increased accumulation of pathogenic gut microbiota and a decrease in beneficial ones. Unfortunately, CRC is likely to be diagnosed at a late stage, increasing CRC-related mortality. However, this alteration in the gut microbiota (gut dysbiosis) can be harnessed as a biomarker for non-invasive diagnosis, prognosis, prevention, and treatment of CRC in an effort to prevent late diagnosis and poor prognosis associated with CRC.

AIM OF REVIEW

This review discusses identification of potential biomarkers by targeting diet-mediated gut dysbiosis for the stage-specific diagnosis, prognosis, treatment, and prevention of CRC. Our findings provide a comprehensive insight into the potential of protumorigenic bacteria (e.g.pathogenic Escherichia coli,enterotoxigenic Bacteroides fragilis and Fusobacterium nucleatum) and their metabolites (e.g., colibactin and B. fragilis toxin) from gut dysbiosis as biomarkers for the diagnosis of CRC.

KEY SCIENTIFIC CONCEPTS OF REVIEW

Collectively, a detailed understanding of the available data from current studies suggests that, further research on quantification of metabolites and stage-specific pathogenic microbial abundance is required for the diagnosis and treatment of CRC based on microbial dysbiosis. Specifically, future studies on faecal samples, from patient with CRC, should be conducted for F. nucleatum among different opportunistic bacteria, given its repeated occurrence in faecal samples and CRC biopsies in numerous studies. Finally, we discuss the potential of faecal microbial transplantation (FMT) as an intervention to restore damaged gut microbiota during CRC treatment and management.

Deficiency of SR-B1 reduced the tumor load of colitis-induced or APCmin /+ -induced colorectal cancer

BACKGROUND

Colorectal cancer (CRC) is one of the most common tumors in the world. Cholesterol plays an important role in the pathogenesis of tumors. One of the cholesterol transporters, scavenger receptor class B type 1 (SR-B1), a multi-ligand membrane receptor protein, is expressed in the intestines which also highly expressed in various tumors. But the potential mechanism of SR-B1 in CRC development has not been reported.

AIMS

This study aimed to clarify the importance of SR-B1 in the development and prognosis of CRC as much as possible to provide a possible strategy in CRC treatment.

MATERIALS & METHODS

In this study, we used SR-B1 gene knockdown mice to study the effect of SR-B1 on colitis-induced or APCmin/+ -induced CRC. The expression of related molecules were detected through the immunohistochemistry and hematoxylin-eosin staining, western blot analysis, and Flow cytometry. The gene expression and microbiota in microenvironment of CRC mice were analyzed through eukaryotic mRNA sequencing and 16S rRNA high-throughput sequencing.

RESULTS

The results showed that SR-B1 knockdown reduced the tumor load of colitis-induced or APCmin/+ -induced CRC. SR-B1 knockdown improved the immune microenvironment by affecting the level of tumor-associated macrophage (TAM), mononuclear myeloid-derived suppressor cells (M-MDSCs), granulocytic myeloid-derived suppressor cells (G-MDSCs), programmed cell death-ligand 1 (PD-L1), and human leukocyte antigen class I-B (HLA-B), and also reduced the level of low-density lipoprotein receptor (LDL-R), and increased the level of ATP binding cassette transporter A1 (ABCA1) to regulate the cholesterol metabolism, and regulated the expression of related genes and intestinal microbiota. SR-B1 knockdown can also trigger the anti-CRC effect of anti-PD 1 in colitis-induced CRC.

DISCUSSION

SR-B1 deficiency significantly improved the immunity in tumor microenvironment of colitis-induced or APCmin/+ -induced CRC. In addition, the microbiota changes caused by SR-B1 deficiency favor improving the immune response to chemotherapeutic drugs and anti-PD1 therapy. The mechanism of action of SR-B1 deficiency on the development of CRC still needs further in-depth research.

CONCLUSION

This study provides a new treatment strategy for treating CRC by affecting the expression of SR-B1 in intestine.

Correlations for untargeted GC × GC-HRTOF-MS metabolomics of colorectal cancer

INTRODUCTION

Modern comprehensive instrumentations provide an unprecedented coverage of complex matrices in the form of high-dimensional, information rich data sets.

OBJECTIVES

In addition to the usual biomarker research that focuses on the detection of the studied condition, we aimed to define a proper strategy to conduct a correlation analysis on an untargeted colorectal cancer case study with a data set of 102 variables corresponding to metabolites obtained from serum samples analyzed with comprehensive two-dimensional gas chromatography coupled to high-resolution time-of-flight mass spectrometry (GC × GC-HRTOF-MS). Indeed, the strength of association existing between the metabolites contains potentially valuable information about the molecular mechanisms involved and the underlying metabolic network associated to a global perturbation, at no additional analytical effort.

METHODS

Following Anscombe's quartet, we took particular attention to four main aspects. First, the presence of non-linear relationships through the comparison of parametric and non-parametric correlation coefficients: Pearson's r, Spearman's rho, Kendall's tau and Goodman-Kruskal's gamma. Second, the visual control of the detected associations through scatterplots and their associated regressions and angles. Third, the effect and handling of atypical samples and values. Fourth, the role of the precision of the data on the attribution of the ranks through the presence of ties.

RESULTS

Kendall's tau was found the method of choice for the data set at hand. Its application highlighted 17 correlations significantly altered in the active state of colorectal cancer (CRC) in comparison to matched healthy controls (HC), from which 10 were specific to this state in comparison to the remission one (R-CRC) investigated on distinct patients. 15 metabolites involved in the correlations of interest, on the 25 unique ones obtained, were annotated (Metabolomics Standards Initiative level 2).

CONCLUSIONS

The metabolites highlighted could be used to better understand the pathology. The systematic investigation of the methodological aspects that we expose allows to implement correlation analysis to various fields and many specific cases.

Association between Probiotics and Modulation of Gut Microbial Community Composition in Colorectal Cancer Animal Models: A Systematic Review (2010-2021)

Background

Colorectal cancer (CRC) is one of the most prevalent gastrointestinal malignancies and is considered the third major cause of mortality globally. Probiotics have been shown to protect against the CRC cascade in numerous studies.

Aims

The goal of this systematic review was to gather the preclinical studies that examined the impact of probiotics on the alteration of gut microbiota profiles (bacterial communities) and their link to colorectal carcinogenesis as well as the potential processes involved.

Methods

The search was performed using Scopus, Web of Science, and PubMed databases. Five parameters were used to develop search filters: "probiotics," "prebiotics," "synbiotics," "colorectal cancer," and "animal model."

Results

Of the 399 full texts that were screened, 33 original articles met the inclusion criteria. According to the current findings, probiotics/synbiotics could significantly attenuate aberrant crypt foci (ACF) formation, restore beneficial bacteria in the microbiota population, increase short-chain fatty acids (SCFAs), and change inflammatory marker expression.

Conclusions

The present systematic review results indicate that probiotics could modulate the gut microbial composition and immune regulation to combat/inhibit CRC in preclinical models. However, where the evidence is more limited, it is critical to transfer preclinical research into clinical data.

Cellular and Molecular Mechanisms of the Tumor Stroma in Colorectal Cancer: Insights into Disease Progression and Therapeutic Targets

Colorectal cancer (CRC) is a major health burden worldwide and is the third most common type of cancer. The early detection and diagnosis of CRC is critical to improve patient outcomes. This review explores the intricate interplay between the tumor microenvironment, stromal interactions, and the progression and metastasis of colorectal cancer. The review begins by assessing the gut microbiome's influence on CRC development, emphasizing its association with gut-associated lymphoid tissue (GALT). The role of the Wnt signaling pathway in CRC tumor stroma is scrutinized, elucidating its impact on disease progression. Tumor budding, its effect on tumor stroma, and the implications for patient prognosis are investigated. The review also identifies conserved oncogenic signatures (COS) within CRC stroma and explores their potential as therapeutic targets. Lastly, the seed and soil hypothesis is employed to contextualize metastasis, accentuating the significance of both tumor cells and the surrounding stroma in metastatic propensity. This review highlights the intricate interdependence between CRC cells and their microenvironment, providing valuable insights into prospective therapeutic approaches targeting tumor-stroma interactions.

Identification of Intestinal Microbial Community in Gallstone Patients with Metagenomic Next-Generation Sequencing

Gallstone disease (GD) is one of the most common gastrointestinal diseases worldwide. Nowadays, intestinal microbiota are thought to play important roles in the formation of gallstones. In our study, human fecal samples were extracted for metagenomic next-generation sequencing (mNGS) on the Illumina HiSeq platform, followed by bioinformatics analyses. Our results showed that there was a particular intestinal micro-ecosystem in GD patients. In contrast to healthy people, the sequences of Bacteroidetes, Bacteroides and Thetaiotaomicron were obviously more abundant in GD patients at phylum, genus and species levels, respectively. On the other hand, the glycan metabolism and drug resistance, especially for the β-lactams, were the most profound functions of gut microbes in GD patients compared to those in normal subjects. Furthermore, a correlation analysis drew out that there existed a significant relationship between the serum levels of biochemical indicators and abundances of intestinal microbes in GD patients. Our results illuminate both the composition and functions of intestinal microbiota in GD patients. All in all, our study can broaden the insight into the potential mechanism of how gut microbes affect the progression of gallstones to some extent, which may provide potential targets for the prevention, diagnosis or treatment of GD.

Targeting microbiome, drug metabolism, and drug delivery in oncology

Recent emerging scientific evidence shows a relationship between gut microbiota (GM) and immunomodulation. In the recently published "Hallmarks of Cancer", the microbiome has been reported to play a crucial role in cancer research, and perspectives for its clinical implementation to improve the effectiveness of pharmacotherapy were explored. Several studies have shown that GM can affect the outcomes of pharmacotherapy in cancer, suggesting that GM may affect anti-tumor immunity. Thus, studies on GM that analyze big data using computer-based analytical methods are required. In order to successfully deliver GM to an environment conducive to the proliferation of immune cells both within and outside the tumor microenvironment (TME), it is crucial to address a variety of challenges associated with distinct delivery methods, specifically those pertaining to oral, endoscopic, and intravenous delivery. Clinical trials are in progress to evaluate the effects of targeting GM and whether it can enhance immunity or act on the TME, thereby to improve the clinical outcomes for cancer patients.

The role of gastric microecological dysbiosis in gastric carcinogenesis

Gastric cancer (GC) is the leading cause of cancer-related death worldwide, and reducing its mortality has become an urgent public health issue. Gastric microecological dysbiosis (including bacteria, fungi, viruses, acid suppressants, antibiotics, and surgery) can lead to gastric immune dysfunction or result in a decrease in dominant bacteria and an increase in the number and virulence of pathogenic microorganisms, which in turn promotes development of GC. This review analyzes the relationship between gastric microecological dysbiosis and GC, elucidates dynamic alterations of the microbiota in Correa's cascade, and identifies certain specific microorganisms as potential biomarkers of GC to aid in early screening and diagnosis. In addition, this paper presents the potential of gastric microbiota transplantation as a therapeutic target for gastric cancer, providing a new direction for future research in this field.

Yacon (Smallanthus sonchifolius) Flour Reduces Inflammation and Had No Effects on Oxidative Stress and Endotoxemia in Wistar Rats with Induced Colorectal Carcinogenesis

Colorectal cancer has a high worldwide incidence. The aim of this study was to determine the effect of yacon flour (YF) on oxidative stress, inflammation, and endotoxemia in rats with induced colorectal cancer (CRC). The Wistar male rats were divided and kept for 8 weeks in four groups: S (basal diet, n = 10), Y (YF flour + basal diet, n = 10), C (CRC-induced control + basal diet, n = 12), CY (CRC-induced animals + YF, n = 12). CRC was induced by intraperitoneal injections of 1,2-dimethylhydrazine (25 mg/kg body weight). Groups Y and CY received 7.5% of the prebiotic FOS from YF. The treatment with YF increased fecal secretory immunoglobulin A levels and decreased lipopolysaccharides, tumor necrosis factor alpha and interleukin-12. However, no effect was observed on the oxidative stress by the total antioxidant capacity of plasma, anion superoxide, and nitric oxide analysis of the animals (p < 0.05). The short-chain fatty acids acetate, propionate, and butyrate showed interactions with NF-κB, TLR4, iNOS, and NADPH oxidase by in silico analysis and had a correlation (by the Person analysis) with CRC markers. The yacon flour treatment reduced the inflammation in rats with induced CRC, and could be a promising food to reduce the damages caused by colorectal cancer.

Role of gut microbiota and bacterial metabolites in mucins of colorectal cancer

Colorectal cancer (CRC) is a major health burden, accounting for approximately 10% of all new cancer cases worldwide. Accumulating evidence suggests that the crosstalk between the host mucins and gut microbiota is associated with the occurrence and development of CRC. Mucins secreted by goblet cells not only protect the intestinal epithelium from microorganisms and invading pathogens but also provide a habitat for commensal bacteria. Conversely, gut dysbiosis results in the dysfunction of mucins, allowing other commensals and their metabolites to pass through the intestinal epithelium, potentially triggering host responses and the subsequent progression of CRC. In this review, we summarize how gut microbiota and bacterial metabolites regulate the function and expression of mucin in CRC and novel treatment strategies for CRC.

Comprehensive Analysis of the Expression, Prognostic Value, and Immune Infiltration Activities of GABRD in Colon Adenocarcinoma

Colon adenocarcinoma (COAD) is one of the tumors with the highest mortality rates. It is of the utmost significance to make an accurate prognostic assessment and to tailor one's treatment to the specific needs of the patient. Multiple lines of evidence point to the possibility that genetic variables and clinicopathological traits are connected to the onset and development of cancer. In the past, a number of studies have revealed that gamma-aminobutyric acid type A receptor subunit delta (GABRD) plays a role in the advancement of a number of different cancers. However, its function in COAD was rarely reported. In this study, we analyzed TCGA datasets and identified 29 survival-related differentially expressed genes (DEGs) in COAD patients. In particular, GABRD expression was noticeably elevated in COAD specimens. There was a correlation between high GABRD expression and an advanced clinical stage. According to the results of the survival tests, patients whose GABRD expression was high had a lower overall survival time and progression-free survival time than those whose GABRD expression was low. GABRD expression was found to be an independent predictive predictor for overall survival, as determined by multivariate COX regression analysis. Additionally, the predictive nomogram model can accurately predict the fate of individuals with COAD. In addition, we observed that GABRD expressions were positively associated with the expression of T cells regulatory (Tregs), macrophages M0, while negatively associated with the expression of T cells CD8, T cells follicular helper, macrophages M1, dendritic cells activated, eosinophils, and T cells CD4 memory activated. The IC50 of BI-2536, bleomycin, embelin, FR-180204, GW843682X, LY317615, NSC-207895, rTRAIL, and VX-11e was higher in the GABRD high-expression group. In conclusion, we have shown evidence that GABRD is a novel biomarker that is connected with immune cell infiltration in COAD and may be utilized to predict the prognosis of COAD patients.

Indole metabolites and colorectal cancer: Gut microbial tryptophan metabolism, host gut microbiome biomarkers, and potential intervention mechanisms

Tryptophan (Trp) functions in host-disease interactions. Its metabolism is a multi-pathway process. Indole and its derivatives are Trp metabolites unique to the human gut microbiota. Changes in Trp metabolism have also been detected in colorectal cancer (CRC). Here, combined with the existing CRC biomarkers, we ascribed it to the altered bacteria having the indole-producing ability by making a genomic prediction. We also reviewed the anti-inflammatory and possible anti-cancer mechanisms of indoles, including their effects on tumor cells, the ability to repair the gut barrier, regulation of the host immune system, and provide resistance against oxidative stress. Indole and its derivatives, along with related bacteria, could be targeted as auxiliary strategies to restrain cancer development in the future.

Involvement of the human microbiome in frequent cancers, current knowledge and carcinogenesis mechanisms

The human body is home to a complex microbial community, living in symbiosis. However, when an imbalance occurs, known as dysbiosis, it can lead to organic diseases such as cancers. Helicobacter pylori is commonly recognized as the causative agent of gastric cancer. Numerous studies have explored the potential role of other microorganisms in cancers. For example, the role of intestinal microbiota in the hepatocellular carcinoma formation and progression, the microbiota in breast cancer and the interaction between the microbiome and TP53 in human lung carcinogenesis. In this review, we highlight the latest findings on the microbiome involved in the most common cancers and the suggested mechanisms of carcinogenesis.

The involvement of Th1 cell differentiation in the anti-tumor effect of purified polysaccharide from Sanghuangporus vaninii in colorectal cancer via multi-omics analysis

Sanghuangporus vaninii is a medicinal mushroom, which has been used as a treatment for various diseases; however, the therapeutic potential and mechanism of action of S. vaninii in colorectal cancer (CRC) remain unknown. Herein, human colon adenocarcinoma cells were used to analyze the anti-CRC effects of the purified polysaccharide of S. vaninii (SVP-A-1) in vitro. In SVP-A-1-treated B6/JGpt-Apc^{em1Cin (Min)}/Gpt male (Apc^Min/+) mice, 16S rRNA sequencing was performed on cecal feces, metabolites were examined in serum, and LC-MS/MS protein detection was performed in colorectal tumors. Protein changes were further confirmed by various biochemical detection methods. Water-soluble SVP-A-1 with a molecular weight of 22.5 kDa was first obtained. SVP-A-1 prevented gut microbiota dysbiosis related to metabolic pathways of L-arginine biosynthesis, increased L-citrulline levels in the serum of Apc^Min/+ mice, mediated L-arginine synthesis, and improved antigen presentation in dendritic cells and activated CD4⁺ T cells; the resulting Th1 cells released IFN-γ and TNF-α to act on tumor cells and promoted the sensitivity of tumor cells to cytotoxic T lymphocytes. In summary, SVP-A-1 exerted anti-CRC effects and has excellent potential for CRC treatment.

The Colorectal Cancer Gut Environment Regulates Activity of the Microbiome and Promotes the Multidrug Resistant Phenotype of ESKAPE and Other Pathogens

The human gut microbiota in colorectal cancer patients have a distinct population compared to heathy counterparts. However, the activity (gene expression) of this community has not been investigated.

Sex Differences in Intestinal Microbiota and Their Association with Some Diseases in a Japanese Population Observed by Analysis Using a Large Dataset

In recent years, many studies have focused on the relationship between intestinal microbiota and human health, but the impact of sex has not yet been sufficiently investigated. In this study, sex differences in the intestinal microbiota of a Japanese population were investigated by age group, using a large dataset constructed for a cross-sectional study. α-diversity analysis indicated that the impact of sex differences varied among the 20s-50s age groups but tended to be smaller among the 60s-70s age groups. Fusobacterium, Megamonas, Megasphaera, Prevotella, and Sutterella were more common among males, whereas Alistipes, Bacteroides, Bifidobacterium, Odoribacter, and Ruthenibacterium were common among females. Next, intestinal bacteria potentially associated with 12 diseases were investigated for each sex. The results indicate that many of these differ between males and females, and among age groups. Thus, sex and age should be considered for studies on intestinal microbiota and disease association, prevention, and treatment approaches that target them.

Systematic Review: Contribution of the Gut Microbiome to the Volatile Metabolic Fingerprint of Colorectal Neoplasia

Colorectal cancer (CRC) has been associated with changes in volatile metabolic profiles in several human biological matrices. This enables its non-invasive detection, but the origin of these volatile organic compounds (VOCs) and their relation to the gut microbiome are not yet fully understood. This systematic review provides an overview of the current understanding of this topic. A systematic search using PubMed, Embase, Medline, Cochrane Library, and the Web of Science according to PRISMA guidelines resulted in seventy-one included studies. In addition, a systematic search was conducted that identified five systematic reviews from which CRC-associated gut microbiota data were extracted. The included studies analyzed VOCs in feces, urine, breath, blood, tissue, and saliva. Eight studies performed microbiota analysis in addition to VOC analysis. The most frequently reported dysregulations over all matrices included short-chain fatty acids, amino acids, proteolytic fermentation products, and products related to the tricarboxylic acid cycle and Warburg metabolism. Many of these dysregulations could be related to the shifts in CRC-associated microbiota, and thus the gut microbiota presumably contributes to the metabolic fingerprint of VOC in CRC. Future research involving VOCs analysis should include simultaneous gut microbiota analysis.

Olfactomedin 4 produces dysplasia but suppresses metastasis of colon cancer

Development of colorectal cancer (CRC) is regulated by a series of genetic and microenvironmental alterations. Olfactomedin 4 (OLFM4) is a secreted glycoprotein that is highly expressed in the gastrointestinal tract and modulates inflammation. However, the role of OLFM4 in CRC is uncertain. Here we aimed to explore the function of OLFM4 in CRC in vivo and in vitro. The mRNA expression of OLFM4 was up-regulated in precursor lesions with dysplasia or ulcerative colitis but was reduced in CRC. OLFM4 neutralizing antibody suppressed inflammation-mediated early-stage CRC formation in an AOM/DSS colitis-associated cancer model. OLFM4 knockdown cells exhibited increased cell proliferation and motility in vitro and in vivo. Ablation of OLFM4 increased tumor growth and metastasis in xenograft experiments. In addition, OLFM4 knockdown cells showed elevated expression of colon cancer stem cell markers including CD133, resulting in increased metastasis via epithelial-mesenchymal transition signaling. This study demonstrated that OLFM4 regulates inflammation and cancer progression differently; ablation of OLFM4 promotes cancer metastasis via stemness and epithelial-mesenchymal transition. These results suggest a new route for controlling cancer progression and metastasis.

Encouraging Tactics with Genetically Modified Probiotics to Improve Immunity for the Prevention of Immune-Related Diseases including Cardio-Metabolic Disorders

The PI3K/AKT/mTOR signaling pathway may play crucial roles in the pathogenesis of obesity and diabetes mellitus, as well as metabolic syndromes, which could also be risk factors for cardio-metabolic disorders. Consistently, it has been shown that beneficial effects may be convoyed by the modulation of the PI3K/AKT/mTOR pathway against the development of these diseases. Importantly, the PI3K/AKT/mTOR signaling pathway can be modulated by probiotics. Probiotics have a variety of beneficial properties, with the potential of treating specific diseases such as immune-related diseases, which are valuable to human health. In addition, an increasing body of work in the literature emphasized the contribution of genetically modified probiotics. There now seems to be a turning point in the research of probiotics. A better understanding of the interactions between microbiota, lifestyle, and host factors such as genetics and/or epigenetics might lead to a novel therapeutic approach with probiotics for these diseases. This study might provide a theoretical reference for the development of genetically modified probiotics in health products and/or in functional foods for the treatment of cardio-metabolic disorders.

Screening and identification of hub gene and differential gene and mutation sequence analysis of related genes in colorectal cancer based on bioinformatics analysis

Background

At present, the research of genomics is in ascendency, and using bioinformatics analysis methods to systematically explore the pathogenic genes and their regulatory mechanisms will play a great role in promoting the research of cancer. This study was to search The Cancer Genome Atlas (TCGA) database and extract inflammation-related non-coding RNA to construct a prognosis model of colon cancer and search for new immunotherapeutic targets.

Methods

The transcriptome sequencing data and clinical data of 396 colon cancer patients were downloaded from TCGA database, and the inflammation-related non-coding RNA was obtained from the non-coding RNAs in Inflammation (ncRI) database. The prognostic model was constructed by univariate Cox regression, least absolute shrinkage and selection operator (LASSO) regression, and multivariate Cox regression, and the optimal grouping threshold of risk score was determined by X-Tile software. The patients were risk stratified to further explore the differences in immune cell infiltration and biological function between the high- and low-risk groups.

Results

The TCGA dataset of colon cancer was included to screen out 120 differentially expressed genes (DEGs) that overlapped in the 2 datasets, among which 29 genes were up-regulated and 91 genes were down-regulated. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis of the above 120 DEGs showed that proximal tubule sodium bicarbonate recovery, nitrogen metabolism, pancreatic fluid secretion, and PPAR signaling pathways were closely related to the occurrence of colon cancer. The expression of copper death-related genes was significantly correlated with the correlation coefficient of colon cancer (P<0.01). Gene Ontology analysis showed that the DEGs were mainly enriched in messenger RNA processing, RNA splicing, small G protein-mediated signal transduction, adhesion junction, mitochondrial matrix, mitochondrial protein complex, chromatin binding, small G protein binding, and Ras G protein binding, among others. KEGG analysis showed that the DEGs were enriched in the following pathways: herpes simplex virus type 1 infection, pathways of neurodegenerative diseases, Huntington's disease, prion disease, Parkinson's disease, the Ras signaling pathway, and so on.

Conclusions

The key genes closely related to colon cancer were effectively screened by the bioinformatics method, which provided a theoretical basis for further study of its mechanism.

Fusobacterium nucleatum and colorectal cancer: From phenomenon to mechanism

Colorectal cancer(CRC) is the third most frequent malignant tumor. The gut microbiome acts as a vital component of CRC etiology. Fusobacterium nucleatum(Fn) is a key member of colorectal cancer-associated bacteria. But we lack a systematic and in-depth understanding on its role in CRC evolution. In this article, We reviewed the abundance changes and distribution of Fn in CRC occurrence and development, potential effect of Fn in the initiation of CRC, the source of intratumoral Fn and the cause of its tropism to CRC. In addition, We described the mechanism by which Fn promotes the malignant biological behavior of CRC, affects CRC response to therapy, and shapes the tumor immune microenvironment in great detail. Based on the relationship between Fn and CRC, we proposed strategies for CRC prevention and treatment, and discussed the feasibility and limitations of specific cases, to gain insights into further basic and clinical research in the future.

Onco-biome in pharmacotherapy for lung cancer: a narrative review

BACKGROUND AND OBJECTIVE

The gut microbiota (GM) was recently recognized to play an important role in modulating systemic immune responses and is known to influence the effects or adverse events of immune checkpoint blockade (ICB) or carcinogenesis by crosstalk with regulators of cancer-related immunity, and this relationship is complex and multifactorial. Diversity in the gut microbiome and the abundance of specific bacterial species have been identified to be associated with better response and prognosis. Therefore, the purpose of the current interest in the gut microbiome is to enable modulation of the immune system in donor cancer patients by the administration of specific bacterial species and enabling their dominance. To understand this "terra incognita" is to uncover the role of the mechanisms underlying unknown organ functions, and this knowledge will lead to enhanced immunotherapy for lung cancer patients.

METHODS

In this article, we summarized the literature on the relationship between the microbiome and lung cancer and the potential of the microbiome as a therapeutic target.

KEY CONTENT AND FINDINGS

This article is organized into the following sections: introduction, methods, microbiota and cancer development, microbiota and lung cancer treatment, future directions, and conclusion.

CONCLUSIONS

The gut microbiome is currently becoming the hallmark of cancer research and has an established and critical role in regulating antitumor immunity and the response to ICB in patients with lung cancers.

Exploring the Association between Gut and Urine Microbiota and Prostatic Disease including Benign Prostatic Hyperplasia and Prostate Cancer Using 16S rRNA Sequencing

Numerous microorganisms residing in the gastrointestinal and genitourinary tracts affect host health. We investigated stool and voided urine samples collected from patients with benign prostatic hyperplasia (BPH) or prostate cancer (PC) and a control group to explore the potential relationship between human microbiota and prostatic disease, and aimed to identify correlations and pathogenic taxonomic units. We studied microbial composition using 16S rRNA sequencing to identify operational taxonomic units (OTUs). Extracted genome was amplified and filtered sequences were used to classify OTUs based on their specific taxonomy. No statistically significant differences were observed in stool samples among the groups. However, urine samples indicated different microbiota compositions in different patient populations. The top five microbial genera that showed significant differences between the BPH and control groups were Alcaligenes, Pseudomonas, Lactobacillus, Akkermansia, and Cetobacterium. Faecalibacterium, Staphylococcus, Ruminococcaceae_UCG_002, Neisseria, and Agathobacter were the genera with the largest proportion differences when comparing the PC and control groups. We discovered that the urine microbiota composition of the BPH and PC groups was distinct from that of the control group. Due to the impact of microbiota on prostatic disease, it is necessary to identify specific microbes for further research.

Use of Personalized Biomarkers in Metastatic Colorectal Cancer and the Impact of AI

Colorectal cancer is a major cause of cancer-related death worldwide and is correlated with genetic and epigenetic alterations in the colonic epithelium. Genetic changes play a major role in the pathophysiology of colorectal cancer through the development of gene mutations, but recent research has shown an important role for epigenetic alterations. In this review, we try to describe the current knowledge about epigenetic alterations, including DNA methylation and histone modifications, as well as the role of non-coding RNAs as epigenetic regulators and the prognostic and predictive biomarkers in metastatic colorectal disease that can allow increases in the effectiveness of treatments. Additionally, the intestinal microbiota’s composition can be an important biomarker for the response to strategies based on the immunotherapy of CRC. The identification of biomarkers in mCRC can be enhanced by developing artificial intelligence programs. We present the actual models that implement AI technology as a bridge connecting ncRNAs with tumors and conducted some experiments to improve the quality of the model used as well as the speed of the model that provides answers to users. In order to carry out this task, we implemented six algorithms: the naive Bayes classifier, the random forest classifier, the decision tree classifier, gradient boosted trees, logistic regression and SVM.

Gut microbiota composition in chemotherapy and targeted therapy of patients with metastatic colorectal cancer

Studies have reported the effects of the gut microbiota on colorectal cancer (CRC) chemotherapy, but few studies have investigated the association between gut microbiota and targeted therapy. This study investigated the role of the gut microbiota in the treatment outcomes of patients with metastatic CRC (mCRC). We enrolled 110 patients with mCRC and treated them with standard cancer therapy. Stool samples were collected before administering a combination of chemotherapy and targeted therapy. Patients who had a progressive disease (PD) or partial response (PR) for at least 12 cycles of therapy were included in the study. We further divided these patients into anti-epidermal growth factor receptor (cetuximab) and anti-vascular endothelial growth factor (bevacizumab) subgroups. The gut microbiota of the PR group and bevacizumab-PR subgroup exhibited significantly higher α-diversity. The β-diversity of bacterial species significantly differed between the bevacizumab-PR and bevacizumab-PD groups (P = 0.029). Klebsiella quasipneumoniae exhibited the greatest fold change in abundance in the PD group than in the PR group. Lactobacillus and Bifidobacterium species exhibited higher abundance in the PD group. The abundance of Fusobacterium nucleatum was approximately 32 times higher in the PD group than in the PR group. A higher gut microbiota diversity was associated with more favorable treatment outcomes in the patients with mCRC. Bacterial species analysis of stool samples yielded heterogenous results. K. quasipneumoniae exhibited the greatest fold change in abundance among all bacterial species in the PD group. This result warrants further investigation especially in a Taiwanese population.

Characteristics of the Gut Microbiota in Japanese Patients with Premenstrual Syndrome

Purpose

The present study aimed to characterize the gut microbiota of individuals with premenstrual syndrome.

Patients and Methods

The gut microbiota of 24 Japanese women with PMS (PMS group) and 144 healthy Japanese women (control group) were compared. Analysis of the α- and β-diversities and the gut microbial composition at the genus level were performed using 16S rRNA gene sequence data obtained from stool samples.

Results

A significant difference in age was observed between the PMS and control groups; however, no significant difference was observed in BMI. The α-diversity measured using the Simpson index was significantly higher in the PMS group than the control group. Visualization of the β-diversity using non-metric multidimensional scaling and permutational multivariate analysis of variance (PERMANOVA) showed that the distance of the gut microbiota between the PMS and control groups is significantly different. Furthermore, a significant difference in the composition of the gut microbiota was observed between the PMS and control groups. At the genus level, the abundances of Collinsella, Bifidobacterium, and Blautia were significantly higher in the PMS group than in the control group. In particular, the abundance of Collinsella in the PMS group was approximately 4.5 times higher than that in the control group. To rule out the confounding effect of age in the abundances of Bifidobacterium, Blautia, and Collinsella, the gut microbiota of the PMS and control groups were compared by age group. Results showed that Collinsella had the highest effect size in participants of 30–40 years of age (mean age: 36.39 ± 4.68 years).

Conclusion

These results suggest that the PMS group possesses a characteristic gut microbiota. In particular, Collinsella was strongly associated with PMS. Since Collinsella has been reported to be associated with diet, dietary interventions such as prebiotics targeting Collinsella may be effective in preventing, improving, and alleviating PMS.

Synthesis and Evaluation of Some New 4H-Pyran Derivatives as Antioxidant, Antibacterial and Anti-HCT-116 Cells of CRC, with Molecular Docking, Antiproliferative, Apoptotic and ADME Investigations

Colorectal cancer oncogenesis is linked to dysbiosis, oxidative stress and overexpression of CDK2. The 4H-pyran scaffold is considered an antitumoral, antibacterial and antioxidant lead as well as a CDK2 inhibitor. Herein, certain 4H-pyran derivatives were evaluated as antibacterial, antioxidant and cytotoxic agents against HCT-116 cells. Derivatives 4g and 4j inhibited all the tested Gram-positive isolates, except for B. cereus (ATCC 14579), with lower IC₅₀ values (µM) than ampicillin. In addition, 4g and 4j demonstrated the strongest DPPH scavenging and reducing potencies, with 4j being more efficient than BHT. In cell viability assays, 4d and 4k suppressed the proliferation of HCT-116 cells, with the lowest IC₅₀ values being 75.1 and 85.88 µM, respectively. The results of molecular docking simulations of 4d and 4k, inhibitory kinase assays against CDK2, along with determination of CDK2 protein concentration and the expression level of CDK2 gene in the lysates of HCT-116 treated cells, suggested that these analogues blocked the proliferation of HCT-116 cells by inhibiting kinase activity and downregulating expression levels of CDK2 protein and gene. Moreover, 4d and 4k were found to induce apoptosis in HCT-116 cells via activation of the caspase-3 gene. Lastly, compounds 4g, 4j, 4d and 4k were predicted to comply with Lipinski’s rule of five, and they are expected to possess excellent physiochemical and pharmacokinetic properties suitable for in vivo bioavailability, as predicted by the SwissADME web tool.

Early life Lactobacillus rhamnosus GG colonisation inhibits intestinal tumour formation

BACKGROUND

Gut microbiota dysbiosis is closely related to the progression of colorectal cancer. Our previous study revealed that early life colonisation with Lactobacillus rhamnosus GG (LGG) had long-term positive effects on health. We sought to investigate whether early life LGG colonisation could inhibit intestinal tumour formation in offspring.

METHODS

Adult C57BL/6 female mice were mated with Apcmin/+ male mice. Pregnant mice with the same conception date received 108 cfu live or fixed LGG from day 18 of pregnancy until natural delivery. After genotyping, offspring mice received 107 cfu of live or fixed LGG for 0-5 days after birth.

RESULTS

Early life LGG colonisation significantly promoted intestinal development, inhibited low-grade intestinal inflammation and altered the gut microbiota composition of offspring in the weaning period (3 week old). Notably, early life LGG colonisation reduced the multiplicity of intestinal tumours in adulthood (12 week old), possibly due to inhibition of Wnt signalling and promotion of tumour cell apoptosis. Importantly, at the genus level, Bifidobacterium and Anaeroplasma with potential anti-tumour effects were increased in adulthood, while Peptostreptococcus, which potentially contributes to tumour formation, was decreased.

CONCLUSIONS

Early life LGG colonisation inhibited the intestinal tumour formation of offspring in adulthood.

The Use of Probiotic Therapy in Metabolic and Neurological Diseases

The human gut is home to trillions of microbes that interact with host cells to influence and contribute to body functions. The number of scientific studies focusing on the gut microbiome has exponentially increased in recent years. Studies investigating factors that may potentially affect the gut microbiome and may be used for therapeutic purposes in diseases where dysbioses in the gut microbiome have been shown are of particular interest. This review compiles current evidence available in the scientific literature on the use of probiotics to treat metabolic diseases and autism spectrum disorders (ASDs) to analyze the efficacy of probiotics in these diseases. To do this, we must first define the healthy gut microbiome before looking at the interplay between the gut microbiome and diseases, and how probiotics affect this interaction. In metabolic diseases, such as obesity and diabetes, probiotic supplementation positively impacts pathological parameters. Conversely, the gut–brain axis significantly impacts neurodevelopmental disorders such as ASDs. However, manipulating the gut microbiome and disease symptoms using probiotics has less pronounced effects on neurodevelopmental diseases. This may be due to a more complex interplay between genetics and the environment in these diseases. In conclusion, the use of microbe-based probiotic therapy may potentially have beneficial effects in ameliorating the pathology of various diseases. Validation of available data for the development of personalized treatment regimens for affected patients is still required.

Bacterial driver-passenger model in biofilms: a new mechanism in the development of colorectal cancer

Colorectal cancer (CRC) is a heterogeneous disease of the intestinal epithelium and ranks the third largest diagnosed malignancy in the world. Many studies have shown that the high risk of CRC is believed to be related to the formation of biofilms. To prove causation, it will be significant to decipher which specific bacteria in biofilms initiate and maintain CRC and fully describe their underlying mechanisms. Here we introduce a bacterial driver-passenger model. This model added a novel and compelling angle to the role of microorganisms, putting more emphasis on the transformation of bacterial composition in biofilms which play different roles in the development of CRC. In this model, bacterial drivers can initiate the formation of CRC through genotoxicity, while bacterial passengers maintain the CRC process through metabolites. On the basis of these pathogens, we further turned our attention to strategies that can inhibit and eradicate these pathogenic biofilms, with the aim of finding new ways to hinder colorectal carcinogenesis.

Microbiota in health and diseases

The role of microbiota in health and diseases is being highlighted by numerous studies since its discovery. Depending on the localized regions, microbiota can be classified into gut, oral, respiratory, and skin microbiota. The microbial communities are in symbiosis with the host, contributing to homeostasis and regulating immune function. However, microbiota dysbiosis can lead to dysregulation of bodily functions and diseases including cardiovascular diseases (CVDs), cancers, respiratory diseases, etc. In this review, we discuss the current knowledge of how microbiota links to host health or pathogenesis. We first summarize the research of microbiota in healthy conditions, including the gut-brain axis, colonization resistance and immune modulation. Then, we highlight the pathogenesis of microbiota dysbiosis in disease development and progression, primarily associated with dysregulation of community composition, modulation of host immune response, and induction of chronic inflammation. Finally, we introduce the clinical approaches that utilize microbiota for disease treatment, such as microbiota modulation and fecal microbial transplantation.

Electronic Nose and Tongue for Assessing Human Microbiota

The technological developments of recent times have allowed the use of innovative approaches to support the diagnosis of various diseases. Many of such clinical conditions are often associated with metabolic unbalance, in turn producing an alteration of the gut microbiota even during asymptomatic stages. As such, studies regarding the microbiota composition in biological fluids obtained by humans are continuously growing, and the methodologies for their investigation are rapidly changing, making it less invasive and more affordable. To this extent, Electronic Nose and Electronic Tongue tools are gaining importance in the relevant field, making them a useful alternative—or support—to traditional analytical methods. In light of this, the present manuscript seeks to investigate the development and use of such tools in the gut microbiota assessment according to the current literature. Significant gaps are still present, particularly concerning the Electronic Tongue systems, however the current evidence highlights the strong potential such tools own to enter the daily clinical practice, with significant advancement concerning the patients’ acceptability and cost saving for healthcare providers.

Species-Level Analysis of the Human Gut Microbiome Shows Antibiotic Resistance Genes Associated With Colorectal Cancer

Colorectal cancer (CRC) is the second leading cause of cancer deaths and continuously increases new cancer cases globally. Accumulating evidence links risks of CRC to antibiotic use. Long-term use and abuse of antibiotics increase the resistance of the gut microbiota; however, whether CRC is associated with antibiotic resistance in gut microbiota is still unclear. In this study, we performed a de novo assembly to metagenomic sequences in 382 CRC patients and 387 healthy controls to obtain representative species-level genome bins (rSGBs) and plasmids and analyzed the abundance variation of species and antibiotic resistance genes (ARGs). Twenty-five species and 65 ARGs were significantly enriched in the CRC patients, and among these ARGs, 12 were multidrug-resistant genes (MRGs), which mainly included acrB, TolC, marA, H-NS, Escherichia coli acrR mutation, and AcrS. These MRGs could confer resistance to fluoroquinolones, tetracyclines, cephalosporins, and rifamycin antibiotics by antibiotic efflux and inactivation. A classification model was built using the abundance of species and ARGs and achieved areas under the curve of 0.831 and 0.715, respectively. Our investigation has identified the antibiotic resistance types of ARGs and suggested that E. coli is the primary antibiotic resistance reservoir of ARGs in CRC patients, providing valuable evidence for selecting appropriate antibiotics in the CRC treatment.

A review on association of fungi with the development and progression of carcinogenesis in the human body

The role and impact of commensal and pathogenic fungi in different parts of the human body are being increasingly appreciated, unveiling the importance of such microorganisms in human health. A key function is the involvement of the mycobiota in cross-kingdom interactions within the microbiome. Any disturbance in the functionality of the microbiota could alter metabolic reactions, have a negative impact on homeostasis or induce diseases. The association of fungi with cancer development is the focus of this review. Several studies have reported direct or indirect involvement of fungal pathogens and mycobiome dysbiosis in induction of carcinogenesis. Most studies focused on cancers of the gastrointestinal tract. However, researchers are now investigating other organs, such as the skin, where the significant results obtained confirm the involvement of fungal pathogens and administration of antifungal drugs in development of cancer. This review gives an overview of the different organs affected and describes the mechanisms used by these eukaryotes or antifungals to induce oncogenesis.

The roles of microbial products in the development of colorectal cancer: a review

A large number of microbes exist in the gut and they have the ability to process and utilize ingested food. It has been reported that their products are involved in colorectal cancer development. The molecular mechanisms which underlie the relationship between gut microbial products and CRC are still not fully understood. The role of some microbial products in CRC is particularly controversial. Elucidating the effects of gut microbiota products on CRC and their possible mechanisms is vital for CRC prevention and treatment. In this review, recent studies are examined in order to describe the contribution metabolites and toxicants which are produced by gut microbes make to CRC, primarily focusing on the involved molecular mechanisms.Abbreviations: CRC: colorectal cancer; SCFAs: short chain fatty acids; HDAC: histone deacetylase; TCA cycle: tricarboxylic acid cycle; CoA: cytosolic acyl coenzyme A; SCAD: short chain acyl CoA dehydrogenase; HDAC: histone deacetylase; MiR-92a: microRNA-92a; KLF4: kruppel-like factor; PTEN: phosphatase and tensin homolog; PI3K: phosphoinositide 3-kinase; PIP2: phosphatidylinositol 4, 5-biphosphate; PIP3: phosphatidylinositol-3,4,5-triphosphate; Akt1: protein kinase B subtype α; ERK1/2: extracellular signal-regulated kinases 1/2; EMT: epithelial-to-mesenchymal transition; NEDD9: neural precursor cell expressed developmentally down-regulated9; CAS: Crk-associated substrate; JNK: c-Jun N-terminal kinase; PRMT1: protein arginine methyltransferase 1; UDCA: ursodeoxycholic acid; BA: bile acids; CA: cholic acid; CDCA: chenodeoxycholic acid; DCA: deoxycholic acid; LCA: lithocholic acid; CSCs: cancer stem cells; MHC: major histocompatibility; NF-κB: NF-kappaB; GPR: G protein-coupled receptors; ROS: reactive oxygen species; RNS: reactive nitrogen substances; BER: base excision repair; DNA: deoxyribonucleic acid; EGFR: epidermal growth factor receptor; MAPK: mitogen activated protein kinase; ERKs: extracellular signal regulated kinases; AKT: protein kinase B; PA: phosphatidic acid; TMAO: trimethylamine n-oxide; TMA: trimethylamine; FMO3: flavin-containing monooxygenase 3; H₂S: Hydrogen sulfide; SRB: sulfate-reducing bacteria; IBDs: inflammatory bowel diseases; NSAID: non-steroidal anti-inflammatory drugs; BFT: fragile bacteroides toxin; ETBF: enterotoxigenic fragile bacteroides; E-cadherin: extracellular domain of intercellular adhesive protein; CEC: colonic epithelial cells; SMOX: spermine oxidase; SMO: smoothened; Stat3: signal transducer and activator of transcription 3; Th17: T helper cell 17; IL17: interleukin 17; AA: amino acid; TCF: transcription factor; CDT: cytolethal distending toxin; PD-L1: programmed cell death 1 ligand 1.

Intersection of FcγRIIB, the microbiome, and checkpoint inhibitors in antitumor immunity

Fc receptors (FcRs) and the microbiome are both known to have an effect on the development and progression of cancers. Checkpoint inhibitors are a novel class of therapeutics which are used to combat cancer and are integrally linked to both FcRs and the microbiome. The use of checkpoint inhibitors has grown exponentially over the past decade, although many host factors affect both the efficacy and the safety of these therapeutics. Some of these host factors, including the microbiome and the expression of FcRs, are currently being investigated. Here we discuss the current understanding of FcRs (particularly the inhibitory FcγRIIB) and the microbiome in context of T cell immunity, inflammation, cancer, and checkpoint inhibition.

Influence of gut and intratumoral microbiota on the immune microenvironment and anti-cancer therapy

Microbiota has been implicated in the regulation of tumor progression and therapeutic efficacy. However, the effect of microbiota on disease progression is context dependent, differing according to tumor types, therapeutic regimens, and composition of the microbiota, calling for a deeper understanding of host-microbiome interactions. Previous studies have demonstrated that gut microbiota influences disease progression by regulating local and systemic immunity. Notably, with the advent of next-generation sequencing technology, intratumoral microbiota has also been found and constitutes an important component of the tumor microenvironment. In this review, we summarize recent knowledge about the identification of intra-tumor microbiota and discuss the role of gut and intratumoral microbiota in solid tumors in the angle of immune microenvironment interaction. Furthermore, we discuss how these findings may benefit current anti-cancer approaches. Key problems to be solved in ongoing and future research are highlighted.

Interaction of Gut Microbiome and Host microRNAs with the Occurrence of Colorectal and Breast Cancer and Their Impact on Patient Immunity

Breast and colorectal cancers are two primary malignancies on which most of the research done worldwide investigates the potential genetic and environmental risk factors and thereby tries to develop therapeutic methods to improve prognosis. Breast cancer is the most diagnosed cancer type in women, while colorectal cancer is diagnosed in males as the third most and females as the second most cancer type. Though these two cancer types are predominantly seen in adult patients worldwide, in the current context, these malignancies are diagnosed at a younger age with a significant rate of incidents than previous. Such early-onset cancers are generally present at an advanced stage of the most aggressive type with a poor prognosis. In the past, the focus of the research was mainly on studying possible candidate genes to understand the onset. However, it is now recognized that genetics, epigenetics, and other environmental factors play a pivotal role in cancer susceptibility. Thus, most studies were diversified to study the behavior of host microRNAs, and the involvement of gut microbiota and good communication between them surfaced in the occurrence and state of the disease. It is understood that the impact of these factors affects the outcome of the disease. Out of the adverse outcomes identified relating to the disease, immunosuppression is one of the most concerning outcomes in the current world, where such individuals remain vulnerable to infections. Recent studies revealed that microbiome and microRNA could create a considerable impact on immunosuppression. This review focused on the behavior of host microRNAs and gut microbiome for the onset of the disease and progression, thereby influencing an individual's immunosuppression. Understanding the interactions among microRNA, microbiome, presentation of the disease, and impact on the immune system will be immensely useful for developing future therapeutic strategies based on targeting host microRNA and the patient's gut microbiome. Therapies such as inhibitory-miRNA therapies, miRNA mimic-based therapeutics, immune checkpoint blockade therapies, and bacteria-assisted tumor-targeted therapies help modulate cancer. At the same time, it paid equal attention to potential noninvasive biomarkers in diagnosis, prognosis, and therapeutics in both cancers.

Gut Microbiota-Mediated Modulation of Cancer Progression and Therapy Efficacy

The role of gut microbiota in the development of various tumors has been a rising topic of public interest, and in recent years, many studies have reported a close relationship between microbial groups and tumor development. Gut microbiota play a role in host metabolism, and the positive and negative alterations of these microbiota have an effect on tumor treatment. The microbiota directly promote, eliminate, and coordinate the efficacy of chemotherapy drugs and the toxicity of adjuvant drugs, and enhance the ability of patients to respond to tumors in adjuvant immunotherapy. In this review, we outline the significance of gut microbiota in tumor development, reveal its impacts on chemotherapy and immunotherapy, and discover various potential mechanisms whereby they influence tumor treatment. This review demonstrates the importance of intestinal microbiota-related research for clinical tumor treatment and provides additional strategy for clinical assistance in cancer treatment.

Escherichia coli and colorectal cancer: Unfolding the enigmatic relationship

Colorectal cancer (CRC) is one of the deadliest cancers in the world. Specific strains of intestinal Escherichia coli (E. coli) may influence the initiation and development of CRC by exploiting virulence factors and inflammatory pathways. Mucosa-associated E. coli strains are more prevalent in CRC biopsies in comparison to healthy controls. Moreover, these strains can survive and replicate within macrophages and induce a pro-inflammatory response. Chronic exposure to inflammatory mediators can lead to increased cell proliferation and cancer. Production of colobactin toxin by the majority of mucosa-associated E. coli isolated from CRC patients is another notable finding. Colibactin-producing E. coli strains, in particular, induce double-strand DNA breaks, stop the cell cycle, involve in chromosomal rearrangements of mammalian cells and are implicated in carcinogenic effects in animal models. Moreover, some enteropathogenic E. coli (EPEC) strains are able to survive and replicate in colon cells as chronic intracellular pathogens and may promote susceptibility to CRC by downregulation of DNA Mismatch Repair (MMR) proteins. In this review, we discuss current evidence and focus on the mechanisms by which E. coli can influence the development of CRC.