Microbe-based therapies for colorectal cancer: Advantages and limitations

Unveiling the intratumoral microbiota within cancer landscapes

Recent advances in cancer research have unveiled a significant yet previously underappreciated aspect of oncology: the presence and role of intratumoral microbiota. These microbial residents, encompassing bacteria, fungi, and viruses within tumor tissues, have been found to exert considerable influence on tumor development, progression, and the efficacy of therapeutic interventions. This review aims to synthesize these groundbreaking discoveries, providing an integrated overview of the identification, characterization, and functional roles of intratumoral microbiota in cancer biology. We focus on elucidating the complex interactions between these microorganisms and the tumor microenvironment, highlighting their potential as novel biomarkers and therapeutic targets. The purpose of this review is to offer a comprehensive understanding of the microbial dimension in cancer, paving the way for innovative approaches in cancer diagnosis and treatment.

PDIA3 driven STAT3/PD-1 signaling promotes M2 TAM polarization and aggravates colorectal cancer progression

OBJECTIVE

This inquiry endeavors to delineate the influence of PDIA3 on tumor-associated macrophages within the realm of colorectal malignancies, whilst elucidating the intrinsic biochemical pathways.

METHOD

Leveraging bioinformatics, we scrutinized the symbiosis between PDIA3, STAT3, and CD274. A xenograft model in immunodeficient murine served to assess PDIA3's impact on colorectal carcinogenesis. Further, Western blot analysis quantified the protein expression of PDIA3, p-STAT3, PD-1, XBP-1, assorted enzymes, and IL-6. Moreover, in vitro assays gauged SW480 cellular dynamics inclusive of migration, invasive potential, and proliferation.

RESULTS

Bioinformatics exploration exposed PDIA3's elevated presence in diverse cancers, with a marked expression in colorectal cancer, as per TCGA and GEO repositories. Correlative studies showed PDIA3 positively aligning with STAT3 and CD274, the latter also associated with monocyte-derived macrophages. Comparative analysis of colorectal neoplasms and normal colon samples unveiled heightened levels of PDIA3 markers which, when overexpressed in SW480 cells, escalated tumorigenicity and oncogenic behaviors, with a noted decrease upon PD-1 monoclonal antibody intervention.

CONCLUSIONS

PDIA3 augments the M2 polarization of tumor-associated macrophages via modulation of the STAT3/PD-1 cascade, thus invigorating the tumorous proliferation and dissemination in colorectal cancer. Such revelations position PDIA3 as an auspicious target for PD-1 blockade therapeutics, offering a promising foundation for rectifying colorectal carcinoma.

A Review of the Use of Native and Engineered Probiotics for Colorectal Cancer Therapy

Colorectal cancer (CRC) is a serious global health concern, and researchers have been investigating different strategies to prevent, treat, or support conventional therapies for CRC. This review article comprehensively covers CRC therapy involving wild-type bacteria, including probiotics and oncolytic bacteria as well as genetically modified bacteria. Given the close relationship between CRC and the gut microbiota, it is crucial to compile and present a comprehensive overview of bacterial therapies used in the context of colorectal cancer. It is evident that the use of native and engineered probiotics for colorectal cancer therapy necessitates research focused on enhancing the therapeutic properties of probiotic strains.. Genetically engineered probiotics might be designed to produce particular molecules or to target cancer cells more effectively and cure CRC patients.

Engineered Luminescent Oncolytic Vaccinia Virus Activation of Photodynamic-Immune Combination Therapy for Colorectal Cancer

Oncolytic virus therapy is currently regarded as a promising approach in cancer immunotherapy. It has greater therapeutic advantages for colorectal cancer that is prone to distant metastasis. However, the therapeutic efficacy and clinical application of viral agents alone for colorectal cancer remain suboptimal. In this study, an engineered oncolytic vaccinia virus (OVV-Luc) that expresses the firefly luciferase gene is developed and loaded Chlorin e6 (Ce6) onto the virus surface through covalent coupling, resulting in OVV-Luc@Ce6 (OV@C). The OV@C infiltrates tumor tissue and induces endogenous luminescence through substrate catalysis, resulting in the production of reactive oxygen species. This unique system eliminates the need for an external light source, making it suitable for photodynamic therapy (PDT) in deep tissues. Moreover, this synergistic effect between PDT and viral immunotherapy enhances dendritic cell maturation, macrophage polarization, and reversal of the immunosuppressive microenvironment. This synergistic effect has the potential to convert a "cold" into a "hot" tumor, it offers valuable insights for clinical translation and application.

Ginsenoside Rk3 modulates gut microbiota and regulates immune response of group 3 innate lymphoid cells to against colorectal tumorigenesis

The gut microbiota plays a pivotal role in the immunomodulatory and protumorigenic microenvironment of colorectal cancer (CRC). However, the effect of ginsenoside Rk3 (Rk3) on CRC and gut microbiota remains unclear. Therefore, the purpose of this study is to explore the potential effect of Rk3 on CRC from the perspective of gut microbiota and immune regulation. Our results reveal that treatment with Rk3 significantly suppresses the formation of colon tumors, repairs intestinal barrier damage, and regulates the gut microbiota imbalance caused by CRC, including enrichment of probiotics such as Akkermansia muciniphila and Barnesiella intestinihominis, and clearance of pathogenic Desulfovibrio. Subsequent metabolomics data demonstrate that Rk3 can modulate the metabolism of amino acids and bile acids, particularly by upregulating glutamine, which has the potential to regulate the immune response. Furthermore, we elucidate the regulatory effects of Rk3 on chemokines and inflammatory factors associated with group 3 innate lymphoid cells (ILC3s) and T helper 17 (Th17) signaling pathways, which inhibits the hyperactivation of the Janus kinase-signal transducer and activator of transcription 3 (JAK-STAT3) signaling pathway. These results indicate that Rk3 modulates gut microbiota, regulates ILC3s immune response, and inhibits the JAK-STAT3 signaling pathway to suppress the development of colon tumors. More importantly, the results of fecal microbiota transplantation suggest that the inhibitory effect of Rk3 on colon tumors and its regulation of ILC3 immune responses are mediated by the gut microbiota. In summary, these findings emphasize that Rk3 can be utilized as a regulator of the gut microbiota for the prevention and treatment of CRC.

The potential role of gut microbiota outer membrane vesicles in colorectal cancer

Colorectal cancer (CRC) is a common malignant digestive tract tumor in colorectal regions. Considerable evidence now shows that the gut microbiota have essential roles in CRC occurrence and development. Most Gram-negative bacteria release outer membrane vesicles (OMVs) via outer membrane blistering, which contain specific cargoes which interact with host cells via intercellular communications, host immune regulation, and gut microbiota homeostasis. Studies have also shown that OMVs selectively cluster near tumor cells, thus cancer treatment strategies based on OMVs have attracted considerable research attention. However, little is known about the possible impact of gut microbiota OMVs in CRC pathophysiology. Therefore, in this review, we summarize the research progress on molecular composition and function of OMV, and review the microbial dysbiosis in CRC. We then focus on the potential role of gut microbiota OMVs in CRC. Finally, we examine the clinical potential of OMVs in CRC treatment, and their main advantages and challenges in tumor therapy.

Unleashing the Potential of Benincasa hispida Peel Extract: Synthesizing Selenium Nanoparticles with Remarkable Antibacterial and Anticancer Properties

In this study, we successfully synthesized selenium nanoparticles (P-SeNPs) using an environment-friendly approach. This method involves utilizing the aqueous peel extract of Benincasa hispida (ash gourd) in combination with selenium salt. Through our innovative procedure, we harnessed the impressive bio-reduction capabilities, therapeutic potential, and stabilizing attributes inherent in B. hispida. This results in the formation of P-SeNPs with distinct and noteworthy qualities. Our findings were thoroughly substantiated through comprehensive characterizations employing various techniques, including ultraviolet-visible spectroscopy (UV-Vis), transmission electron microscopy (TEM), dynamic light scattering (DLS), zeta potential analysis, and Fourier transform infrared spectroscopy (FTIR). The nanoparticles exhibited a spherical shape, considerable size (22.32 ± 2 nm), uniform distribution, and remarkable stability (-24 mV), all of which signify the effective integration of the phytoconstituents of B. hispida. Furthermore, P-SeNPs displayed robust antibacterial efficacy against pathogenic bacterial strains, as indicated by their low minimum inhibitory concentration values. Our research also revealed the remarkable ability of P-SeNPs to fight cancer, as demonstrated by their impressive IC50 value of 0.19 µg/mL against HeLa cells, while showing no harm to primary human osteoblasts, while simultaneously demonstrating no toxicity toward primary human osteoblasts. These pivotal findings underscore the transformative nature of P-SeNPs, which holds promise for targeted antibacterial treatment and advancements in cancer therapeutics. The implications of these nanoparticles extend to their potential applications in therapies, diagnostics, and various biomedical contexts. Notably, the environmentally sustainable synthesis process and exceptional properties established this study as a significant milestone in the field of nanomedicine, paving the way for a more promising and health-enhancing future.

Chemopreventive effect of a milk whey by-product derived from Buffalo (Bubalus bubalis) in protecting from colorectal carcinogenesis

BACKGROUND

Several studies show that natural foods are a source of compounds with anticancer properties that affect the gut microbiota and its metabolites. In the present study, we investigate the effect of a delactosed buffalo milk whey by-product (DMW) on colorectal carcinogenesis.

METHODS

The effect of DMW on colorectal carcinoma (CRC) was investigated in the established mouse model of azoxymethane (AOM)-induced colon carcinoma, which closely resembles the human clinical condition of CRC. The effect of DMW on CRC immortalized cell lines was also evaluated to further identify the antineoplastic mechanism of action.

RESULTS

Pretreatment of AOM-treated mice with DMW significantly (P < 0.05) reduced the percentage of mice bearing both aberrant crypt foci with more than four crypts (which are early precancerous lesions that progress to CRC) and tumors. In addition, DMW completely counteracted the effect of AOM on protein expression of caspase-9, cleaved caspase-3 and poly ADP-ribose polymerase in colonic tissue. Administration of DMW alone (i.e. without AOM) resulted in changes in the composition of the gut microbiota, leading to enrichment or depletion of genera associated with health and disease, respectively. DMW was also able to restore AOM-induced changes in specific genera of the gut microbiota. Specifically, DMW reduced the genera Atopobiaceae, Ruminococcus 1 and Lachnospiraceae XPB1014 and increased the genera Parabacteroides and Candidatus Saccharimonas, which were increased and reduced, respectively, by AOM. Blood levels of butyric acid and cancer diagnostic markers (5-methylcytidine and glycerophosphocholine), which were increased by AOM treatment, were reduced by DMW. Furthermore, DMW exerted cytotoxic effects on two human CRC cell lines (HCT116 and HT29) and these effects were associated with the induction of apoptotic signaling.

CONCLUSIONS

Our results suggest that DMW exerts chemopreventive effects and restores the gut microbiota in AOM-induced CRC, and induces cytotoxic effect on CRC cells. DMW could be an important dietary supplement to support a healthy gut microbiota and reduce the prevalence of CRC in humans. Video Abstract.

Plants against cancer: the immune-boosting herbal microbiome: not of the plant, but in the plant. Basic concepts, introduction, and future resource for vaccine adjuvant discovery

The presence of microorganism communities (MOCs) comprised of bacteria, fungi, archaea, algae, protozoa, viruses, and the like, are ubiquitous in all living tissue, including plant and animal. MOCs play a significant role in establishing innate and acquired immunity, thereby influencing susceptibility and resistance to disease. This understanding has fostered substantial advancements in several fields such as agriculture, food science/safety, and the development of vaccines/adjuvants, which rely on administering inactivated-attenuated MOC pathogens. Historical evidence dating back to the 1800s, including reports by Drs Busch, Coley, and Fehleisen, suggested that acute febrile infection in response to "specific microbes" could trigger spontaneous tumor remission in humans. This discovery led to the purposeful administration of the same attenuated strains, known as "Coley's toxin," marking the onset of the first microbial (pathogen) associated molecular pattern (MAMPs or PAMPs)-based tumor immunotherapy, used clinically for over four decades. Today, these same MAMPS are consumed orally by billions of consumers around the globe, through "specific" mediums (immune boosting "herbal supplements") as carriers of highly concentrated MOCs accrued in roots, barks, hulls, sea algae, and seeds. The American Herbal Products Association (AHPA) mandates microbial reduction in botanical product processing but does not necessitate the removal of dead MAMP laden microbial debris, which we ingest. Moreover, while existing research has focused on the immune-modulating role of plant phytochemicals, the actual immune-boosting properties might instead reside solely in the plant's MOC MAMP laden biomass. This assertion is logical, considering that antigenic immune-provoking epitopes, not phytochemicals, are known to stimulate immune response. This review explores a neglected area of research regarding the immune-boosting effects of the herbal microbiome - a presence which is indirectly corroborated by various peripheral fields of study and poses a fundamental question: Given that food safety focuses on the elimination of harmful pathogens and crop science acknowledges the existence of plant microbiomes, what precisely are the immune effects of ingesting MAMPs of diverse structural composition and concentration, and where are these distributed in our botanicals? We will discuss the topic of concentrated edible MAMPs as acid and thermally stable motifs found in specific herbs and how these would activate cognate pattern recognition receptors (PPRs) in the upper gut-associated lymphoid tissue (GALT), including Peyer's patches and the lamina propria, to boost antibody titers, CD8+ and CD4+ T cells, NK activity, hematopoiesis, and facilitating M2 to M1 macrophage phenotype transition in a similar manner as vaccines. This new knowledge could pave the way for developing bioreactor-grown/heat-inactivated MOC therapies to boost human immunity against infections and improve tumor surveillance.

Therapeutic efficacy of caffeic acid phenethyl ester in cancer therapy: An updated review

Nowadays, there is a lot of public and scientific interest in using phytochemicals to treat human ailments. Existing cancer medicines still run across obstacles, despite significant advancements in the field. For instance, chemotherapy may result in severe adverse effects, increased drug resistance, and treatment failure. Natural substances that are phytochemically derived provide innovative approaches as potent therapeutic molecules for the treatment of cancer. Bioactive natural compounds may enhance chemotherapy for cancer by increasing the sensitivity of cancer cells to medicines. Propolis has been found to interfere with the viability of cancer cells, among other phytochemicals. Of all the components that make up propolis, caffeic acid phenethyl ester (CAPE) (a flavonoid) has been the subject of the most research. It demonstrates a broad spectrum of therapeutic uses, including antitumor, antimicrobial, antiviral, anti-inflammatory, immunomodulatory, hepatoprotective, neuroprotective, and cardioprotective effects. Studies conducted in vitro and in vivo have demonstrated that CAPE specifically targets genes involved in cell death, cell cycle regulation, angiogenesis, and metastasis. By altering specific signaling cascades, such as the NF-κB signaling pathway, CAPE can limit the proliferation of human cancer cells. This review highlights the research findings demonstrating the anticancer potential of CAPE with a focus on multitargeted molecular and biological implications in various cancer models.

SAELGMDA: Identifying human microbe-disease associations based on sparse autoencoder and LightGBM

Introduction

Identification of complex associations between diseases and microbes is important to understand the pathogenesis of diseases and design therapeutic strategies. Biomedical experiment-based Microbe-Disease Association (MDA) detection methods are expensive, time-consuming, and laborious.

Methods

Here, we developed a computational method called SAELGMDA for potential MDA prediction. First, microbe similarity and disease similarity are computed by integrating their functional similarity and Gaussian interaction profile kernel similarity. Second, one microbe-disease pair is presented as a feature vector by combining the microbe and disease similarity matrices. Next, the obtained feature vectors are mapped to a low-dimensional space based on a Sparse AutoEncoder. Finally, unknown microbe-disease pairs are classified based on Light Gradient boosting machine.

Results

The proposed SAELGMDA method was compared with four state-of-the-art MDA methods (MNNMDA, GATMDA, NTSHMDA, and LRLSHMDA) under five-fold cross validations on diseases, microbes, and microbe-disease pairs on the HMDAD and Disbiome databases. The results show that SAELGMDA computed the best accuracy, Matthews correlation coefficient, AUC, and AUPR under the majority of conditions, outperforming the other four MDA prediction models. In particular, SAELGMDA obtained the best AUCs of 0.8358 and 0.9301 under cross validation on diseases, 0.9838 and 0.9293 under cross validation on microbes, and 0.9857 and 0.9358 under cross validation on microbe-disease pairs on the HMDAD and Disbiome databases. Colorectal cancer, inflammatory bowel disease, and lung cancer are diseases that severely threat human health. We used the proposed SAELGMDA method to find possible microbes for the three diseases. The results demonstrate that there are potential associations between Clostridium coccoides and colorectal cancer and one between Sphingomonadaceae and inflammatory bowel disease. In addition, Veillonella may associate with autism. The inferred MDAs need further validation.

Conclusion

We anticipate that the proposed SAELGMDA method contributes to the identification of new MDAs.

How the interplay among the tumor microenvironment and the gut microbiota influences the stemness of colorectal cancer cells

Colorectal cancer (CRC) remains the third most prevalent cancer disease and involves a multi-step process in which intestinal cells acquire malignant characteristics. It is well established that the appearance of distal metastasis in CRC patients is the cause of a poor prognosis and treatment failure. Nevertheless, in the last decades, CRC aggressiveness and progression have been attributed to a specific cell population called CRC stem cells (CCSC) with features like tumor initiation capacity, self-renewal capacity, and acquired multidrug resistance. Emerging data highlight the concept of this cell subtype as a plastic entity that has a dynamic status and can be originated from different types of cells through genetic and epigenetic changes. These alterations are modulated by complex and dynamic crosstalk with environmental factors by paracrine signaling. It is known that in the tumor niche, different cell types, structures, and biomolecules coexist and interact with cancer cells favoring cancer growth and development. Together, these components constitute the tumor microenvironment (TME). Most recently, researchers have also deepened the influence of the complex variety of microorganisms that inhabit the intestinal mucosa, collectively known as gut microbiota, on CRC. Both TME and microorganisms participate in inflammatory processes that can drive the initiation and evolution of CRC. Since in the last decade, crucial advances have been made concerning to the synergistic interaction among the TME and gut microorganisms that condition the identity of CCSC, the data exposed in this review could provide valuable insights into the biology of CRC and the development of new targeted therapies.

Updates on Plant-Based Protein Products as an Alternative to Animal Protein: Technology, Properties, and Their Health Benefits

Plant-based protein products, represented by "plant meat", are gaining more and more popularity as an alternative to animal proteins. In the present review, we aimed to update the current status of research and industrial growth of plant-based protein products, including plant-based meat, plant-based eggs, plant-based dairy products, and plant-based protein emulsion foods. Moreover, the common processing technology of plant-based protein products and its principles, as well as the emerging strategies, are given equal importance. The knowledge gap between the use of plant proteins and animal proteins is also described, such as poor functional properties, insufficient texture, low protein biomass, allergens, and off-flavors, etc. Furthermore, the nutritional and health benefits of plant-based protein products are highlighted. Lately, researchers are committed to exploring novel plant protein resources and high-quality proteins with enhanced properties through the latest scientific and technological interventions, including physical, chemical, enzyme, fermentation, germination, and protein interaction technology.

Tumor-targeting engineered probiotic Escherichia coli Nissle 1917 inhibits colorectal tumorigenesis and modulates gut microbiota homeostasis in mice

AIMS

Preliminary studies have identified the use of probiotics as a potential treatment strategy against colorectal cancer (CRC). However, natural probiotics lack direct tumor-targeting and tumor-killing activity in the intestine. This study aimed to construct a tumor-targeting engineered probiotic to combat CRC.

MAIN METHODS

Standard adhesion assay was performed to analyze the adherence ability of tumor-binding protein HlpA to CT26 cells. CCK-8 assay, Hoechst 33258 staining and flow cytometry analysis were used for examining cytotoxicity of tumoricidal protein azurin toward CT26 cells. An engineered probiotic Ep-AH harboring azurin and hlpA genes was developed using Escherichia coli Nissle 1917 (EcN) chassis. Antitumor effects of Ep-AH were evaluated in the azoxymethane (AOM) and dextran sodium sulfate salt (DSS)-induced CRC mice. Moreover, analysis of gut microbiota was conducted via fecal 16S rRNA gene sequencing and shotgun metagenomic sequencing.

KEY FINDINGS

Azurin caused a dose-dependent increase of apoptosis in CT26 cells. Ep-AH treatment reversed weight loss (p < 0.001), fecal occult blood (p < 0.01), and shortening of colon length (p < 0.001) than model group, as well as reducing tumorigenesis by 36 % (p < 0.001). Both Ep-H and Ep-A (EcN expressing HlpA or azurin) were less effective than Ep-AH. Furthermore, Ep-AH enriched the members of beneficial bacteria (e.g., Blautia and Bifidobacterium) and reversed abnormal changes of genes associated with several metabolic pathways (e.g., lipopolysaccharide biosynthesis).

SIGNIFICANCE

These results demonstrated that Ep-AH had excellent therapeutic benefits on cancer remission and gut microbiota modulation. Our study provides an effective strategy for anti-CRC treatment.

A New Treatment Landscape for RCC: Association of the Human Microbiome with Improved Outcomes in RCC

Microbes play different roles in metabolism, local or systemic inflammation, and immunity, and the human microbiome in tumor microenvironment (TME) is important for modulating the response to immunotherapy in cancer patients. Renal cell carcinoma (RCC) is an immunogenic tumor, and immunotherapy is the backbone of its treatment. Correlations between the microbiome and responsiveness to immune checkpoint inhibitors have been reported. This review summarizes the recent therapeutic strategies for RCC and the effects of TME on the systemic therapy of RCC. The current understanding and advances in microbiome research and the relationship between the microbiome and the response to immunotherapy for RCC are also discussed. Improving our understanding of the role of the microbiome in RCC treatment will facilitate the development of microbiome targeting therapies to modify the tumor microbiome and improve treatment outcomes.

Computational Simulation of Colorectal Cancer Biomarker Particle Mobility in a 3D Model

Even though some methods for the detection of colorectal cancer have been used clinically, most of the techniques used do not consider the in situ detection of colorectal cancer (CRC) biomarkers, which would favor in vivo real-time monitoring of the carcinogenesis process and consequent studies of the disease. In order to give a scientific and computational framework ideal for the evaluation of diagnosis techniques based on the early detection of biomarker molecules modeled as spherical particles from the computational point of view, a computational representation of the rectum, stool and biomarker particles was developed. As consequence of the transport of stool, there was a displacement of CRC biomarker particles that entered the system as a result of the cellular apoptosis processes in polyps with a length lower than 1 cm, reaching a maximum velocity of 3.47×10-3 m/s. The biomarkers studied showed trajectories distant to regions of the polyp of origin in 1 min of simulation. The research results show that the biomarker particles for CRC respond to the variations in the movements of the stool with trajectories and speeds that depend on the location of the injury, which will allow locating the regions with the highest possibilities of catching particles through in situ measurement instruments in the future.

Gut microbiome in tumorigenesis and therapy of colorectal cancer

Colorectal cancer (CRC) is the malignant tumor with the highest incidence in the digestive system, and the gut microbiome plays a crucial role in CRC tumorigenesis and therapy. The gastrointestinal tract is the organ harboring most of the microbiota in humans. Changes in the gut microbiome in CRC patients suggest possible host-microbe interactions, thereby hinting the potential tumorigenesis, which provides new perspective for preventing, diagnosing, or treating CRC. In this review, we discuss the effects of gut microbiome dysbiosis on CRC, and reveal the mechanisms by which gut microbiome dysbiosis leads to CRC. Gut microbiome modulation with the aim to reverse the established gut microbial dysbiosis is a novel strategy for the prevention and treatment of CRC. In addition, this review summarizes that probiotic antagonize CRC tumorigenesis by protecting intestinal barrier function, inhibiting cancer cell proliferation, resisting oxidative stress, and enhancing host immunity. Finally, we highlight clinical applications of the gut microbiome, such as gut microbiome analysis-based biomarker screening and prediction, and microbe modulation-based CRC prevention, treatment enhancement, and treatment side effect reduction. This review provides the reference for the clinical application of gut microbiome in the prevention and treatment of CRC.

Virus-inspired strategies for cancer therapy

The intentional use of viruses for cancer therapy dates back over a century. As viruses are inherently immunogenic and naturally optimized delivery vehicles, repurposing viruses for drug delivery, tumor antigen presentation, or selective replication in cancer cells represents a simple and elegant approach to cancer treatment. While early virotherapy was fraught with harsh side effects and low response rates, virus-based therapies have recently seen a resurgence due to newfound abilities to engineer and tune oncolytic viruses, virus-like particles, and virus-mimicking nanoparticles for improved safety and efficacy. However, despite their great potential, very few virus-based therapies have made it through clinical trials. In this review, we present an overview of virus-inspired approaches for cancer therapy, discuss engineering strategies to enhance their mechanisms of action, and highlight their application for overcoming the challenges of traditional cancer therapies.

Antitumor effects of fecal microbiota transplantation: Implications for microbiome modulation in cancer treatment

Fecal microbiome transplantation (FMT) from healthy donors is one of the techniques for restoration of the dysbiotic gut, which is increasingly being used to treat various diseases. Notably, mounting evidence in recent years revealed that FMT has made a breakthrough in the oncology treatment area, especially by improving immunotherapy efficacy to achieve antitumor effects. However, the mechanism of FMT in enhancing antitumor effects of immune checkpoint blockers (ICBs) has not yet been fully elucidated. This review systematically summarizes the role of microbes and their metabolites in the regulation of tumor immunity. We highlight the mechanism of action of FMT in the treatment of refractory tumors as well as in improving the efficacy of immunotherapy. Furthermore, we summarize ongoing clinical trials combining FMT with immunotherapy and further focus on refined protocols for the practice of FMT in cancer treatment, which could guide future directions and priorities of FMT scientific development.

Clinical Significance of Serum Haptoglobin and Protein Disulfide-Isomerase A3 in the Screening, Diagnosis, and Staging of Colorectal Cancer

Objective: This study aims to explore the clinical significance of haptoglobin (HP) and protein disulfide-isomerase A3 (PDIA3) in human serum in the screening, diagnosis and staging of colorectal cancer (CRC), and to provide novel screening approaches featuring high specificity, sensitivity, and accuracy for early screening and diagnosis of clinical colorectal cancer.

Methods: 88, 77, and 36 blood specimens were respectively harvested from colorectal cancer patients, colorectal polyp patients, and normal subjects (the health examination) who requested medical assistance from our hospital between Oct2019 and February 2022. The serum contents of HP and PDIA3 in each sample were determined through an enzyme linked immunosorbent assay (ELISA). This step was taken to analyze the differences among different specimen groups in terms of the serum contents of HP and PDIA3, to analyze the relationships between the expression levels of HP and PDIA3 and the pathological characteristics of colorectal cancer, and to explore the critical role of HP and PDIA3 in the screening, diagnosis, and staging of colorectal cancer.

Results: Serum contents of HP and PDIA3 were higher in colorectal cancer patients, with statistical differences (p < 0.05), than those in the colonic polyp patients and healthy subjects. Receiver operating characteristic (ROC) curve demonstrated that the cut-offs of HP and PDIA3 serum contents indicating colorectal cancer were 149 ug/ml and 66 ng/ml respectively. The individually and jointly tested AUCs of HP (0.802) and PDIA3 (0.727) were higher than those of serum CEA and CA199, the sensitivity and specificity of HP were 64.8 and 91.2%, the sensitivity and specificity of PDIA3 were 65.9 and 71.7%. Moreover, the contents of HP and PDIA3 increased alongside disease progression, with differences (p < 0.05).

Conclusion: Our research indicated that joint testing of HP and PDIA3 was of reference value for progressive stage and reliable biological indicators of colorectal cancer screening.

Phytochemical Screening, Nutritional Value, Anti-Diabetic, Anti-Cancer, and Anti-Bacterial Assessment of Aqueous Extract from Abelmoschus esculentus Pods

Known for its high nutritional and medicinal value, okra (Abelmoschus esculentus) is commonly used for replacing plasma and expanding blood volume in humans. It is a major economic crop cultivated in tropical and subtropical regions worldwide. The present study aimed to investigate and evaluate the nutritional properties and prospective applications of the consumable parts of okra. The total ash content (mineral content), carbohydrate, crude fiber, fat, protein, and moisture fractions of okra pod aqueous extract were determined. The results show that okra aqueous extract contained 84.670–87.650% moisture, 1.514–1.197% ash, 7.857–8.261% carbohydrate, 2.367–3.410% crude protein, and 6.781–8.314% crude fiber. Okra was determined to have high nutritional value, with γ-tocopherol and α-tocopherol contents about 2.67 mg/100 g and 1.62 mg/100 g, respectively. High-performance liquid chromatography (HPLC) was performed to determine the sugars present in okra aqueous extract. The water-soluble polysaccharide content was 10.22–16.45 g/100 g. The tested aqueous extract was a rich source of total phenolic compounds in gallic acid equivalents (288.2–3426.2 mg/100 g), chlorophyll a (3.53 mg/100), chlorophyll b (2.43 mg/100), and carotenoids (1.3 mg/100 g). The detected minerals were Ca, Mg, Cu, Zn, Fe, K, Na, and Mn. Atomic absorption spectrometry analysis of these ashed minerals was performed. In addition to the nutritional benefits, okra pods exhibited antimicrobial, anticancer, and antioxidant properties. The aqueous extract was found to be potentially active against bacterial strains of Staphylococcus aureus (MIC value = 21.8 mg/mL), Escherichia coli (MIC value = 18.7 mg/mL), Bacillus cereus (MIC value = 20.7 mg/mL), and Klebsiella pneumoniae (MIC value = 20.2 mg/mL). Okra aqueous extract exhibited inhibitory activity against α-amylase (IC50 = 120 µg/mL) and α-glucosidase (IC50 = 115 µg/mL). The okra extract exhibited high anticancer activity, concentration-dependent and with an IC50 value of about 158.3 mg/mL. The results indicated that okra pods have nutritional and medicinal properties and, hence, can be used as a functional food and broad-spectrum nutraceutical supplement.

Microbial-Driven Immunological Memory and Its Potential Role in Microbiome Editing for the Prevention of Colorectal Cancer

Over the last several years, many advances have been made in understanding the role of bacteria in the pathogenesis of gastrointestinal cancers. Beginning with Helicobacter pylori being recognized as the first bacterial carcinogen and the causative agent of most gastric cancers, more recent studies have examined the role of enteric microbes in colorectal cancer. In the digestive tract, these communities are numerous and have a complex interrelationship with local immune/inflammatory responses that impact the health of the host. As modifying the microbiome in the stomach has decreased the risk of gastric cancer, modifying the distal microbiome may decrease the risk of colorectal cancers. To date, very few studies have considered the notion that mucosal lymphocyte-dependent immune memory may confound attempts to change the microbial components in these communities. The goal of this review is to consider some of the factors impacting host-microbial interactions that affect colorectal cancer and raise questions about how immune memory responses to the local microbial consortium affect any attempt to modify the composition of the intestinal microbiome.