Lithocholic Acid, a Metabolite of the Microbiome, Increases Oxidative Stress in Breast Cancer

Exploring the role of a novel postbiotic bile acid: Interplay with gut microbiota, modulation of the farnesoid X receptor, and prospects for clinical translation

The gut microbiota, mainly resides in the colon, possesses a remarkable ability to metabolize different substrates to create bioactive substances, including short-chain fatty acids, indole-3-propionic acid, and secondary bile acids. In the liver, bile acids are synthesized from cholesterol and then undergo modification by the gut microbiota. Beyond those reclaimed by the enterohepatic circulation, small percentage of bile acids escaped reabsorption, entering the systemic circulation to bind to several receptors, such as farnesoid X receptor (FXR), thereby exert their biological effects. Gut microbiota interplays with bile acids by affecting their synthesis and determining the production of secondary bile acids. Reciprocally, bile acids shape out the structure of gut microbiota. The interplay of bile acids and FXR is involved in the development of multisystemic conditions, encompassing metabolic diseases, hepatobiliary diseases, immune associated disorders. In the review, we aim to provide a thorough review of the intricate crosstalk between the gut microbiota and bile acids, the physiological roles of bile acids and FXR in mammals' health and disease, and the clinical translational considerations of gut microbiota-bile acids-FXR in the treatment of the diseases.

Implications of the microbiome and metabolic intermediaries produced by bacteria in breast cancer

The breast microbiome presents a diverse microbial community that could affects health and disease states, in the context of breast cancer. Sequencing technologies have allowed describing the diversity and abundance of microbial communities among individuals. The complex tumoral microenvironment that includes the microbial composition could influence tumor growth. The imbalance of diversity and abundance inside the microbial community, known as dysbiosis plays a crucial role in this context. One the most prevalent bacterial genera described in breast invasive carcinoma are Bacillus, Pseudomonas, Brevibacillus, Mycobacterium, Thermoviga, Acinetobacter, Corynebacterium, Paenibacillus, Ensifer, and Bacteroides. Paenibacills genus shows a relation with patient survival. When the Paenibacills genus increases its abundance in patients with breast cancer, the survival probability decreases. Within this dysbiotic environment, various bacterial metabolites could play a pivotal role in the progression and modulation of breast cancer. Key bacterial metabolites, such as cadaverine, lipopolysaccharides (LPS), and trimethylamine N-oxide (TMAO), have been found to exhibit potential interactions within breast tissue microenvironments. Understanding the intricate relationships between dysbiosis and these metabolites in breast cancer may open new avenues for diagnostic biomarkers and therapeutic targets. Further research is essential to unravel the specific roles and mechanisms of these microbial metabolites in breast cancer progression.

Cytostatic Bacterial Metabolites Interfere with 5-Fluorouracil, Doxorubicin and Paclitaxel Efficiency in 4T1 Breast Cancer Cells

The microbiome is capable of modulating the bioavailability of chemotherapy drugs, mainly due to metabolizing these agents. Multiple cytostatic bacterial metabolites were recently identified that have cytostatic effects on cancer cells. In this study, we addressed the question of whether a set of cytostatic bacterial metabolites (cadaverine, indolepropionic acid and indoxylsulfate) can interfere with the cytostatic effects of the chemotherapy agents used in the management of breast cancer (doxorubicin, gemcitabine, irinotecan, methotrexate, rucaparib, 5-fluorouracil and paclitaxel). The chemotherapy drugs were applied in a wide concentration range to which a bacterial metabolite was added in a concentration within its serum reference range, and the effects on cell proliferation were assessed. There was no interference between gemcitabine, irinotecan, methotrexate or rucaparib and the bacterial metabolites. Nevertheless, cadaverine and indolepropionic acid modulated the Hill coefficient of the inhibitory curve of doxorubicin and 5-fluorouracil. Changes to the Hill coefficient implicate alterations to the kinetics of the binding of the chemotherapy agents to their targets. These effects have an unpredictable significance from the clinical or pharmacological perspective. Importantly, indolepropionic acid decreased the IC50 value of paclitaxel, which is a potentially advantageous combination.

Bile acid profiles and mRNA expression of bile acid-related genes in the liver of dairy cows with high versus normal body condition

Bile acids (BA) play a crucial role not only in lipid digestion but also in the regulation of overall energy homeostasis, including glucose and lipid metabolism. The aim of this study was to investigate BA profiles and mRNA expression of BA-related genes in the liver of high versus normal body condition in dairy cows. We hypothesized that body condition and the transition from gestation to lactation affect hepatic BA concentrations as well as the mRNA abundance of BA-related receptors, regulatory enzymes, and transporters. Therefore, we analyzed BA in the liver as well as the mRNA abundance of BA-related synthesizing enzymes, transporters, and receptors in the liver during the transition period in cows with different body conditions around calving. In a previously established animal model, 38 German Holstein cows were divided into groups with high body condition score (BCS) (HBCS; n = 19) or normal BCS (NBCS; n = 19) based on BCS and backfat thickness (BFT). Cows were fed diets aimed at achieving the targeted differences in BCS and BFT (NBCS: BCS <3.5, BFT <1.2 cm; HBCS: BCS >3.75, BFT >1.4 cm) until they were dried off at wk 7 before parturition. Both groups were fed identical diets during the dry period and subsequent lactation. Liver biopsies were taken at wk -7, 1, 3, and 12 relative to parturition. For BA measurement, a targeted metabolomics approach with LC-ESI-MS/MS was used to analyze BA in the liver. The mRNA abundance of targeted genes related to BA-synthesizing enzymes, transporters, and receptors in the liver was analyzed using microfluidic quantitative PCR. In total, we could detect 14 BA in the liver: 6 primary and 8 secondary BA, with glycocholic acid (GCA) being the most abundant one. The increase of glycine-conjugated BA after parturition, in parallel to increasing serum glycine concentrations may originate from an enhanced mobilization of muscle protein to meet the high nutritional requirements in early lactating cows. Higher DMI in NBCS cows compared with HBCS cows was associated with higher liver BA concentrations such as GCA, deoxycholic acid (DCA), and cholic acid (CA). The mRNA abundance of BA-related enzymes measured herein suggests the dominance of the alternative signaling pathway in the liver of HBCS cows. Overall, BA profiles and BA metabolism in the liver depend on both, the body condition and lactation-induced effects in periparturient dairy cows.

Microbiome in cancer: A comparative analysis between humans and dogs

Cancer is a major cause of death in humans and animals worldwide. While cancer survival rates have increased over recent decades, further research to identify risk factors for the onset and progression of disease, and safe and highly efficacious treatments, is needed. Spontaneous tumours in pets represent an excellent model for neoplastic disease in humans. In this regard, dogs are an interesting species, as the divergence between the dog and human genome is low, humans and dogs have important similarities in the development and functioning of the immune system, and both species often share the same physical environment. There is also a higher homology between the canine and human microbiome than murine model. This review aims to describe and organize recently published information on canine microbiome assemblages and their relationship with the onset and progression of colorectal cancer, breast cancer and lymphoma, and to compare this with human disease. In both species, dysbiosis can induce variations in the gut microbiota that strongly influence shifts in status between health and disease. This can produce an inflammatory state, potentially leading to neoplasia, especially in the intestine, thus supporting canine studies in comparative oncology. Intestinal dysbiosis can also alter the efficacy and side effects of cancer treatments. Fewer published studies are available on changes in the relevant microbiomes in canine lymphoma and mammary cancer, and further research in this area could improve our understanding of the role of microbiota in the development of these cancers.

The Role of Bacteria in Central Nervous System Tumors: Opportunities and Challenges

Tumors of the central nervous system (CNS) are severe and refractory diseases with poor prognosis, especially for patients with malignant glioblastoma and brain metastases. Currently, numerous studies have explored the potential role of bacteria and intestinal flora in tumor development and treatment. Bacteria can penetrate the blood-brain barrier (BBB), targeting the hypoxic microenvironment at the core of tumors, thereby eliminating tumors and activating both the innate and adaptive immune responses, rendering them promising therapeutic agents for CNS tumors. In addition, engineered bacteria and derivatives, such as bacterial membrane proteins and bacterial spores, can also be used as good candidate carriers for targeted drug delivery. Moreover, the intestinal flora can regulate CNS tumor metabolism and influence the immune microenvironment through the "gut-brain axis". Therefore, bacterial anti-tumor therapy, engineered bacterial targeted drug delivery, and intervention of the intestinal flora provide therapeutic modalities for the treatment of CNS tumors. In this paper, we performed a comprehensive review of the mechanisms and therapeutic practices of bacterial therapy for CNS tumors and discussed potential future research directions in this field.

The bacterial metabolite, lithocholic acid, has antineoplastic effects in pancreatic adenocarcinoma

Lithocholic acid (LCA) is a secondary bile acid. LCA enters the circulation after bacterial synthesis in the gastrointestinal tract, reaches distantly located cancer cells, and influences their behavior. LCA was considered carcinogenic, but recent studies demonstrated that LCA has antitumor effects. We assessed the possible role of LCA in pancreatic adenocarcinoma. At the serum reference concentration, LCA induced a multi-pronged antineoplastic program in pancreatic adenocarcinoma cells. LCA inhibited cancer cell proliferation and induced mesenchymal-to-epithelial (MET) transition that reduced cell invasion capacity. LCA induced oxidative/nitrosative stress by decreasing the expression of nuclear factor, erythroid 2-like 2 (NRF2) and inducing inducible nitric oxide synthase (iNOS). The oxidative/nitrosative stress increased protein nitration and lipid peroxidation. Suppression of oxidative stress by glutathione (GSH) or pegylated catalase (pegCAT) blunted LCA-induced MET. Antioxidant genes were overexpressed in pancreatic adenocarcinoma and decreased antioxidant levels correlated with better survival of pancreatic adenocarcinoma patients. Furthermore, LCA treatment decreased the proportions of cancer stem cells. Finally, LCA induced total and ATP-linked mitochondrial oxidation and fatty acid oxidation. LCA exerted effects through the farnesoid X receptor (FXR), vitamin D receptor (VDR), and constitutive androstane receptor (CAR). LCA did not interfere with cytostatic agents used in the chemotherapy of pancreatic adenocarcinoma. Taken together, LCA is a non-toxic compound and has antineoplastic effects in pancreatic adenocarcinoma.

The interactions between traditional Chinese medicine and gut microbiota in cancers: Current status and future perspectives

The gut microbiota, known as the "forgotten organ" and "human second genome," comprises a complex microecosystem. It significantly influences the development of various tumors, including colorectal, liver, stomach, breast, and lung cancers, through both direct and indirect mechanisms. These mechanisms include the "gut-liver" axis, the "lung-intestine" axis, and interactions with the immune system. The intestinal flora exhibits dual roles in cancer, both promoting and suppressing its progression. Traditional Chinese medicine (TCM) can alter cancer progression by regulating the intestinal flora. It modifies the intestinal flora's composition and structure, along with the levels of endogenous metabolites, thus affecting the intestinal barrier, immune system, and overall body metabolism. These actions contribute to TCM's significant antitumor effects. Moreover, the gut microbiota metabolizes TCM components, enhancing their antitumor properties. Therefore, exploring the interaction between TCM and the intestinal flora offers a novel perspective in understanding TCM's antitumor mechanisms. This paper succinctly reviews the association between gut flora and the development of tumors, including colorectal, liver, gastric, breast, and lung cancers. It further examines current research on the interaction between TCM and intestinal flora, with a focus on its antitumor efficacy. It identifies limitations in existing studies and suggests recommendations, providing insights into antitumor drug research and exploring TCM's antitumor effectiveness. Additionally, this paper aims to guide future research on TCM and the gut microbiota in antitumor studies.

Bile acid metabolism and signaling in health and disease: molecular mechanisms and therapeutic targets

Bile acids, once considered mere dietary surfactants, now emerge as critical modulators of macronutrient (lipid, carbohydrate, protein) metabolism and the systemic pro-inflammatory/anti-inflammatory balance. Bile acid metabolism and signaling pathways play a crucial role in protecting against, or if aberrant, inducing cardiometabolic, inflammatory, and neoplastic conditions, strongly influencing health and disease. No curative treatment exists for any bile acid influenced disease, while the most promising and well-developed bile acid therapeutic was recently rejected by the FDA. Here, we provide a bottom-up approach on bile acids, mechanistically explaining their biochemistry, physiology, and pharmacology at canonical and non-canonical receptors. Using this mechanistic model of bile acids, we explain how abnormal bile acid physiology drives disease pathogenesis, emphasizing how ceramide synthesis may serve as a unifying pathogenic feature for cardiometabolic diseases. We provide an in-depth summary on pre-existing bile acid receptor modulators, explain their shortcomings, and propose solutions for how they may be remedied. Lastly, we rationalize novel targets for further translational drug discovery and provide future perspectives. Rather than dismissing bile acid therapeutics due to recent setbacks, we believe that there is immense clinical potential and a high likelihood for the future success of bile acid therapeutics.

Efficacy and mechanisms of cannabis oil for alleviating side effects of breast cancer chemotherapy (CBC2): protocol for randomized controlled trial

BACKGROUND

In a pilot study using both cannabidiol (CBD) and tetrahydrocannabinol (THC) as single agents in advanced cancer patients undergoing palliative care in Thailand, the doses were generally well tolerated, and the outcome measure of total symptom distress scores showed overall symptom benefit. The current study aims to determine the intensity of the symptoms experienced by breast cancer patients, to explore the microbiome profile, cytokines, and bacterial metabolites before and after the treatment with cannabis oil or no cannabis oil, and to study the pharmacokinetics parameters and pharmacogenetics profile of the doses.

METHODS

A randomized, double-blinded, placebo-controlled trial will be conducted on the breast cancer cases who were diagnosed with breast cancer and currently receiving chemotherapy at King Chulalongkorn Memorial Hospital (KCMH), Bangkok, Thailand. Block randomization will be used to allocate the patients into three groups: Ganja Oil (THC 2 mg/ml; THC 0.08 mg/drop, and CBD 0.02 mg/drop), Metta Osot (THC 81 mg/ml; THC 3 mg/drop), and placebo oil. The Edmonton Symptom Assessment System (ESAS), Food Frequency Questionnaires (FFQ), microbiome profile, cytokines, and bacterial metabolites will be assessed before and after the interventions, along with pharmacokinetic and pharmacogenetic profile of the treatment during the intervention.

TRIAL REGISTRATION

TCTR20220809001.

The anticancer activity of bile acids in drug discovery and development

Bile acids (BAs) constitute essential components of cholesterol metabolites that are synthesized in the liver, stored in the gallbladder, and excreted into the intestine through the biliary system. They play a crucial role in nutrient absorption, lipid and glucose regulation, and the maintenance of metabolic homeostasis. In additional, BAs have demonstrated the ability to attenuate disease progression such as diabetes, metabolic disorders, heart disease, and respiratory ailments. Intriguingly, recent research has offered exciting evidence to unveil their potential antitumor properties against various cancer cell types including tamoxifen-resistant breast cancer, oral squamous cell carcinoma, cholangiocarcinoma, gastric cancer, colon cancer, hepatocellular carcinoma, prostate cancer, gallbladder cancer, neuroblastoma, and others. Up to date, multiple laboratories have synthesized novel BA derivatives to develop potential drug candidates. These derivatives have exhibited the capacity to induce cell death in individual cancer cell types and display promising anti-tumor activities. This review extensively elucidates the anticancer activity of natural BAs and synthetic derivatives in cancer cells, their associated signaling pathways, and therapeutic strategies. Understanding of BAs and their derivatives activities and action mechanisms will evidently assist anticancer drug discovery and devise novel treatment.

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.

Mechanism of ferroptosis in breast cancer and research progress of natural compounds regulating ferroptosis

Breast cancer is the most prevalent cancer worldwide and its incidence increases with age, posing a significant threat to women's health globally. Due to the clinical heterogeneity of breast cancer, the majority of patients develop drug resistance and metastasis following treatment. Ferroptosis, a form of programmed cell death dependent on iron, is characterized by the accumulation of lipid peroxides, elevated levels of iron ions and lipid peroxidation. The underlying mechanisms and signalling pathways associated with ferroptosis are intricate and interconnected, involving various proteins and enzymes such as the cystine/glutamate antiporter, glutathione peroxidase 4, ferroptosis inhibitor 1 and dihydroorotate dehydrogenase. Consequently, emerging research suggests that ferroptosis may offer a novel target for breast cancer treatment; however, the mechanisms of ferroptosis in breast cancer urgently require resolution. Additionally, certain natural compounds have been reported to induce ferroptosis, thereby interfering with breast cancer. Therefore, this review not only discusses the molecular mechanisms of multiple signalling pathways that mediate ferroptosis in breast cancer (including metastasis, invasion and proliferation) but also elaborates on the mechanisms by which natural compounds induce ferroptosis in breast cancer. Furthermore, this review summarizes potential compound types that may serve as ferroptosis inducers in future tumour cells, providing lead compounds for the development of ferroptosis-inducing agents. Last, this review proposes the potential synergy of combining natural compounds with traditional breast cancer drugs in the treatment of breast cancer, thereby suggesting future directions and offering new insights.

Gut Metabolite Indoxyl Sulfate Has Selective Deleterious and Anticancer Effect on Colon Cancer Cells

There are a number of reports about anticancer activity of indole derivatives. In this study, we investigated the role of indoxyl sulfate (IS) for its selective anticancer activity on colon cancer cells. IS treatment on HCT-116 and HT-29 human epithelial adenocarcinoma cells led to a decrease in cell proliferation, cell viability, and ATP content. Colon cancer cells showed a 10% increase in cell apoptosis in comparison to control. Due to IS treatment, cell morphology got distorted, cell number found decreased, intracellular vesicles formed, and cells were found floating in the media. Cells also showed a loss in membrane integrity and a decrease in colony-forming ability and ceased at the G2/M phase of the cell cycle. No significant change was noted in the level of inflammatory cytokines IL-17A, IL-1β, and TNF-α, histology, length of intestine, and spleen after 100 mM IS treatment to balb/c mice. These observations indicate the selective anticancer effect of IS on colon cancer cells.

Research status of indole-modified natural products

Indole is a heterocyclic compound formed by the fusion of a benzene ring and pyrrole ring, which has rich biological activity. Many indole-containing compounds have been sold on the market due to their excellent pharmacological activity. For example, vincristine and reserpine have been widely used in clinical practice. The diverse structures and biological activities of natural products provide abundant resources for the development of new drugs. Therefore, this review classifies natural products by structure, and summarizes the research progress of indole-containing natural product derivatives, their biological activities, structure-activity relationship and research mechanism which has been studied in the past 13 years, so as to provide a basis for the development of new drug development.

Identification of a bile acid and bile salt metabolism-related lncRNA signature for predicting prognosis and treatment response in hepatocellular carcinoma

Bile acids and salts have been shown to play a role in liver carcinogenesis through DNA damage, inflammation, and tumor proliferation. However, the correlation between bile acid metabolism and hepatocellular carcinoma (HCC) prognosis remains unclear. This study aimed to identify a predictive signature of bile acid and bile salt metabolism-related long non-coding RNAs (lncRNAs) for HCC prognosis and treatment response. The study used HCC RNA-sequencing data and corresponding clinical and prognostic data from The Cancer Genome Atlas. A prognostic model consisting of five bile acid and bile salt metabolism-related lncRNAs was developed and evaluated in a training set, a validation set and an external set. The model demonstrated good performance in predicting HCC prognosis and was shown to be an independent biomarker for prognosis. Additionally, our study revealed a significant association between the signature and immune cell infiltration, as well as its predictive value for therapeutic responses to both immunotherapy and chemotherapy. Furthermore, three LncRNAs (LUCAT1, AL031985.3 and AC015908.3) expression levels in our signature were validated through qRT-PCR in a cohort of 50 pairs of HCC patient tumor samples and corresponding adjacent non-tumor samples, along with 10 samples of normal liver tissue adjacent to benign lesions. These findings suggest that this novel bile acid and bile salt metabolism-related lncRNA signature can independently predict the prognosis of patients with HCC and may be utilized as a potential predictor of response to treatment in this setting.

Current and future research on the association between gut microbiota and breast cancer

Breast cancer (BC) is a prevalent malignancy. There exists a strong association between gut microbiota (GM) and the development of BC. The GM composition in individuals with BC significantly differs from that in their healthy counterparts. Furthermore, the distribution of GM varies significantly among individuals with different types of BC. The GM can impact BC through metabolite secretion, the gut-mammary axis, and other pathways. Modulating the GM can serve as a very promising potential therapeutic strategy in the treatment of BC. This article will summarize existing research, focusing on the relationship between intestinal microbiota and BC. At the same time, the project will also analyze the application value of intestinal microorganisms in BC intervention work, so as to provide a reference for the further development of BC prevention and treatment work.

Bile acid metabolism regulatory network orchestrates bone homeostasis

Bile acids (BAs), synthesized in the liver and modified by the gut microbiota, have been widely appreciated not only as simple lipid emulsifiers, but also as complex metabolic regulators and momentous signaling molecules, which play prominent roles in the complex interaction among several metabolic systems. Recent studies have drawn us eyes on the diverse physiological functions of BAs, to enlarge the knowledge about the "gut-bone" axis due to the participation about the gut microbiota-derived BAs to modulate bone homeostasis at physiological and pathological stations. In this review, we have summarized the metabolic processes of BAs and highlighted the crucial roles of BAs targeting bile acid-activated receptors, promoting the proliferation and differentiation of osteoblasts (OBs), inhibiting the activity of osteoclasts (OCs), as well as reducing articular cartilage degradation, thus facilitating bone repair. In addition, we have also focused on the bidirectional effects of BA signaling networks in coordinating the dynamic balance of bone matrix and demonstrated the promising effects of BAs on the development or treatment for pathological bone diseases. In a word, further clinical applications targeting BA metabolism or modulating gut metabolome and related derivatives may be developed as effective therapeutic strategies for bone destruction diseases.

Influence of poly-L-ornithine-bile acid nano hydrogels on cellular bioactivity and potential pharmacological applications

Aim: Cellular bioactivity and pathophysiological changes associated with chronic disorders are considered pivotal detrimental factors when developing novel formulations for biomedical applications. Methods: This paper investigates the use of bile acids and synthetic polypeptide poly-L-ornithine (PLO) in formulations and their impacts on a variety of cell lines, with a particular focus on their cellular bioactivity. Results: The hepatic cell line was the most negatively affected by the presence of PLO, while the muscle and beta-pancreatic cell lines did not show as profound of a negative impact of PLO on cellular viability. PLO was the least disruptive regarding mitochondrial function for muscle and beta cells. Conclusion: The addition of bile acids generally decreased mitochondrial respiration and altered bioenergetic parameters in all cell lines.

The biocompatibility and the metabolic impact of thermoresponsive, bile acid-based nanogels on auditory and macrophage cell lines

Deoxycholic acid (DCA), lithocholic acid (LCA), and ursodeoxycholic acid (UDCA) are bile acids that may serve as permeation enhancers when incorporated within the nanogel matrix for drug delivery in the inner ear. In this study, thermoresponsive nanogels were formulated with DCA, LCA and UDCA and their rheological properties and biocompatibility were assessed. The impact of nanogel on cellular viability was evaluated via cell viability assay, the impact of nanogels on cellular bioenergetic parameters was estimated by Seahorse mito-stress test and glycolysis-stress test, while the presence of intracellular free radicals was assessed by reactive oxygen species assay. Nanogels showed a high level of biocompatibility after 24-hour exposure to auditory and macrophage cell lines, with minimal cytotoxicity compared to untreated control. Incubation with nanogels did not alter cellular respiration and glycolysis of the auditory cell line but showed possible mitochondrial dysfunction in macrophages, suggesting tissue-dependent effects of bile acids. Bile acid-nanogels had minimal impact on intracellular reactive oxygen species, with LCA demonstrating the most pro-oxidative behaviour. This study suggests that thermoresponsive nanogels with bile acid, particularly DCA and UDCA, may be promising candidates for inner ear drug delivery.

Natural compounds targeting nuclear receptors for effective cancer therapy

Human nuclear receptors (NRs) are a family of forty-eight transcription factors that modulate gene expression both spatially and temporally. Numerous biochemical, physiological, and pathological processes including cell survival, proliferation, differentiation, metabolism, immune modulation, development, reproduction, and aging are extensively orchestrated by different NRs. The involvement of dysregulated NRs and NR-mediated signaling pathways in driving cancer cell hallmarks has been thoroughly investigated. Targeting NRs has been one of the major focuses of drug development strategies for cancer interventions. Interestingly, rapid progress in molecular biology and drug screening reveals that the naturally occurring compounds are promising modern oncology drugs which are free of potentially inevitable repercussions that are associated with synthetic compounds. Therefore, the purpose of this review is to draw our attention to the potential therapeutic effects of various classes of natural compounds that target NRs such as phytochemicals, dietary components, venom constituents, royal jelly-derived compounds, and microbial derivatives in the establishment of novel and safe medications for cancer treatment. This review also emphasizes molecular mechanisms and signaling pathways that are leveraged to promote the anti-cancer effects of these natural compounds. We have also critically reviewed and assessed the advantages and limitations of current preclinical and clinical studies on this subject for cancer prophylaxis. This might subsequently pave the way for new paradigms in the discovery of drugs that target specific cancer types.

Identification of Bacterial Metabolites Modulating Breast Cancer Cell Proliferation and Epithelial-Mesenchymal Transition

Breast cancer patients are characterized by the oncobiotic transformation of multiple microbiome communities, including the gut microbiome. Oncobiotic transformation of the gut microbiome impairs the production of antineoplastic bacterial metabolites. The goal of this study was to identify bacterial metabolites with antineoplastic properties. We constructed a 30-member bacterial metabolite library and screened the library compounds for effects on cell proliferation and epithelial-mesenchymal transition. The metabolites were applied to 4T1 murine breast cancer cells in concentrations corresponding to the reference serum concentrations. However, yric acid, glycolic acid, d-mannitol, 2,3-butanediol, and trans-ferulic acid exerted cytostatic effects, and 3-hydroxyphenylacetic acid, 4-hydroxybenzoic acid, and vanillic acid exerted hyperproliferative effects. Furthermore, 3-hydroxyphenylacetic acid, 4-hydroxybenzoic acid, 2,3-butanediol, and hydrocinnamic acid inhibited epithelial-to-mesenchymal (EMT) transition. We identified redox sets among the metabolites (d-mannitol-d-mannose, 1-butanol-butyric acid, ethylene glycol-glycolic acid-oxalic acid), wherein only one partner within the set (d-mannitol, butyric acid, glycolic acid) possessed bioactivity in our system, suggesting that changes to the local redox potential may affect the bacterial secretome. Of the nine bioactive metabolites, 2,3-butanediol was the only compound with both cytostatic and anti-EMT properties.

The Emerging Role of the Microbiota in Breast Cancer Progression

Emerging evidence suggests a profound association between the microbiota composition in the gastrointestinal tract and breast cancer progression. The gut microbiota plays a crucial role in modulating the immune response, releasing metabolites, and modulating estrogen levels, all of which have implications for breast cancer growth. However, recent research has unveiled a novel aspect of the relationship between the microbiota and breast cancer, focusing on microbes residing within the mammary tissue, which was once considered sterile. These localized microbial communities have been found to change in the presence of a tumor as compared to healthy mammary tissue, unraveling their potential contribution to tumor progression. Studies have identified specific bacterial species that are enriched within breast tumors and have highlighted the mechanisms by which even these microbes influence cancer progression through immune modulation, direct carcinogenic activity, and effects on cellular pathways involved in cell proliferation or apoptosis. This review aims to provide an overview of the current knowledge on the mechanisms of crosstalk between the gut/mammary microbiota and breast cancer. Understanding this intricate interplay holds promise for developing innovative therapeutic approaches.

Impact of gut microbiome in the development and treatment of pancreatic cancer: Newer insights

The gut microbiome plays an important role in the variation of pharmacologic response. This aspect is especially important in the era of precision medicine, where understanding how and to what extent the gut microbiome interacts with drugs and their actions will be key to individualizing therapy. The impact of the composition of the gut microbiome on the efficacy of newer cancer therapies such as immune checkpoint inhibitors and chimeric antigen receptor T-cell treatment has become an active area of research. Pancreatic adenocarcinoma (PAC) has a poor prognosis even in those with potentially resectable disease, and treatment options are very limited. Newer studies have concluded that there is a synergistic effect for immunotherapy in combination with cytotoxic drugs, in the treatment of PAC. A variety of commensal microbiota can affect the efficacy of conventional chemotherapy and immunotherapy by modulating the tumor microenvironment in the treatment of PAC. This review will provide newer insights on the impact that alterations made in the gut microbial system have in the development and treatment of PAC.

Optimization and Impurity Control Strategy for Lithocholic Acid Production Using Commercially Plant-Sourced Bisnoralcohol

In this study, lithocholic acid (LCA) was prepared using commercially available plant-sourced bisnoralcohol (BA), and the overall yield of the product was 70.6% for five steps. To prevent process-related impurities, the isomerizations of catalytic hydrogenation in the C4-C5 double bond and reduction of the 3-keto group were optimized. The double bond reduction isomerization was improved (5β-H:5α-H = 97:3) using palladium-copper nanowires (Pd-Cu NWs) instead of Pd/C. The reduction of the 3-keto group was 100% converted to a 3α-OH product by 3α-hydroxysteroid dehydrogenase/carbonyl reductase catalysis. Moreover, the impurities during the optimization process were comprehensively studied. Compared with the reported synthesis methods, our developed method significantly improved the isomer ratio and overall yield, affording ICH-grade quality of LCA, and it is more cost-effective and suitable for large-scale production of LCA.

The Interplay between Microbiota and Chemotherapy-Derived Metabolites in Breast Cancer

The most common cancer in women is breast cancer, which is also the second leading cause of death in this group. It is, however, important to note that some women will develop or will not develop breast cancer regardless of whether certain known risk factors are present. On the other hand, certain compounds are produced by bacteria in the gut, such as short-chain fatty acids, secondary bile acids, and other metabolites that may be linked to breast cancer development and mediate the chemotherapy response. Modeling the microbiota through dietary intervention and identifying metabolites directly associated with breast cancer and its complications may be useful to identify actionable targets and improve the effect of antiangiogenic therapies. Metabolomics is therefore a complementary approach to metagenomics for this purpose. As a result of the combination of both techniques, a better understanding of molecular biology and oncogenesis can be obtained. This article reviews recent literature about the influence of bacterial metabolites and chemotherapy metabolites in breast cancer patients, as well as the influence of diet.

PARP2 poly(ADP-ribosyl)ates nuclear factor erythroid 2-related factor 2 (NRF2) affecting NRF2 subcellular localization

PARP2 is a member of the PARP enzyme family. Although, PARP2 plays role in DNA repair, it has regulatory roles in mitochondrial and lipid metabolism, it has pivotal role in bringing about the adverse effects of pharmacological PARP inhibitors. Previously, we showed that the ablation of PARP2 induces oxidative stress and, consequently, mitochondrial fragmentation. In attempt to identify the source of the reactive species we assessed the possible role of a central regulator of cellular antioxidant defense, nuclear factor erythroid 2-related factor 2 (NRF2). The silencing of PARP2 did not alter either the mRNA or the protein expression of NRF2, but changed its subcellular localization, decreasing the proportion of nuclear, active fraction of NRF2. Pharmacological inhibition of PARP2 partially restored the normal localization pattern of NRF2 and in line with that, we showed that NRF2 is PARylated that is absent in the cells in which PARP2 was silenced. Apparently, the PARylation of NRF2 by PARP2 has pivotal role in regulating the subcellular (nuclear) localization of NRF2. The silencing of PARP2 rearranged the expression of genes encoding proteins with antioxidant function, among these a subset of NRF2-dependent genes.

The pro- and antineoplastic effects of deoxycholic acid in pancreatic adenocarcinoma cell models

BACKGROUND

Commensal bacteria secrete metabolites that reach distant cancer cells through the circulation and influence cancer behavior. Deoxycholic acid (DCA), a hormone-like metabolite, is a secondary bile acid specifically synthesized by intestinal microbes. DCA may have both pro- and antineoplastic effects in cancers.

METHODS AND RESULTS

The pancreatic adenocarcinoma cell lines, Capan-2 and BxPC-3, were treated with 0.7 µM DCA, which corresponds to the reference concentration of DCA in human serum. DCA influenced the expression of epithelial to mesenchymal transition (EMT)-related genes, significantly decreased the expression level of the mesenchymal markers, transcription factor 7- like 2 (TCF7L2), snail family transcriptional repressor 2 (SLUG), CLAUDIN-1, and increased the expression of the epithelial genes, zona occludens 1 (ZO-1) and E-CADHERIN, as shown by real-time PCR and Western blotting. Consequently, DCA reduced the invasion capacity of pancreatic adenocarcinoma cells in Boyden chamber experiments. DCA induced the protein expression of oxidative/nitrosative stress markers. Moreover, DCA reduced aldehyde dehydrogenase 1 (ALDH1) activity in an Aldefluor assay and ALDH1 protein level, suggesting that DCA reduced stemness in pancreatic adenocarcinoma. In Seahorse experiments, DCA induced all fractions of mitochondrial respiration and glycolytic flux. The ratio of mitochondrial oxidation and glycolysis did not change after DCA treatment, suggesting that cells became hypermetabolic.

CONCLUSION

DCA induced antineoplastic effects in pancreatic adenocarcinoma cells by inhibiting EMT, reducing cancer stemness, and inducing oxidative/nitrosative stress and procarcinogenic effects such as hypermetabolic bioenergetics.

Exosomes derived from mesenchymal stromal cells: a promising treatment for pelvic floor dysfunction

Pelvic floor dysfunction (PFDs), which include pelvic organ prolapse (POP), stress urinary incontinence (SUI) and anal incontinence (AI), are common degenerative diseases in women that have dramatic effects on quality of life. The pathology of PFDs is based on impaired pelvic connective tissue supportive strength due to an imbalance in extracellular matrix (ECM) metabolism, the loss of a variety of cell types, such as fibroblasts, muscle cells, peripheral nerve cells, and oxidative stress and inflammation in the pelvic environment. Fortunately, exosomes, which are one of the major secretions of mesenchymal stromal cells (MSCs), are involved in intercellular communication and the modulation of molecular activities in recipient cells via their contents, which are bioactive proteins and genetic factors such as mRNAs and miRNAs. These components modify fibroblast activation and secretion, facilitate ECM modelling, and promote cell proliferation to enhance pelvic tissue regeneration. In this review, we focus on the molecular mechanisms and future directions of exosomes derived from MSCs that are of great value in the treatment of PFD.

Role of Gut Microbiota in Breast Cancer and Drug Resistance

Breast cancer is the most common malignancy in women worldwide. The cause of cancer is multifactorial. An early diagnosis and the appropriate treatment of cancer can improve the chances of survival. Recent studies have shown that breast cancer is influenced by the microbiota. Different microbial signatures have been identified in the breast microbiota, which have different patterns depending on the stage and biological subgroups. The human digestive system contains approximately 100 trillion bacteria. The gut microbiota is an emerging field of research that is associated with specific biological processes in many diseases, including cardiovascular disease, obesity, diabetes, brain disease, rheumatoid arthritis, and cancer. In this review article, we discuss the impact of the microbiota on breast cancer, with a primary focus on the gut microbiota’s regulation of the breast cancer microenvironment. Ultimately, updates on how immunotherapy can affect the breast cancer-based microbiome and further clinical trials on the breast and microbiome axis may be an important piece of the puzzle in better predicting breast cancer risk and prognosis.

Probiotics and Prebiotics: Any Role in Menopause-Related Diseases?

PURPOSE OF REVIEW

The aim of this review is to provide an overview of the menopause-related changes in microbiota and their role in the pathogenesis of menopause-related diseases. In addition, evidence on probiotic supplementation as a therapeutic strategy is discussed.

RECENT FINDINGS

The human microbiota is a complex community that lives in a mutualism relationship with the host. Menopause is associated with dysbiosis, and these changes in the composition of microbiota in different sites (gut, vaginal, and oral microbiota) might play a role in the pathogenesis of menopause-related diseases (i.e., osteoporosis, breast cancer, endometrial hyperplasia, periodontitis, and cardiometabolic diseases). The present review highlights the pivotal role of microbiota in postmenopausal women health, in particular it (a) may increase intestinal calcium absorption thus preventing osteoporosis, (b) is associated with reduced risk of breast cancer and type 1 endometrial hyperplasia, (c) reduces gingival inflammation and menopausal periodontitis, and (d) beneficially affects multiple cardiometabolic risk factors (i.e., obesity, inflammation, and blood glucose and lipid metabolism). However, whether oral probiotic supplementation might be used for the treatment of menopause-related dysbiosis requires further clarification.

Half sandwich-type osmium, ruthenium, iridium and rhodium complexes with bidentate glycosyl heterocyclic ligands induce cytostasis in platinum-resistant ovarian cancer cells and bacteriostasis in Gram-positive multiresistant bacteria

The toxicity of and resistance to platinum complexes as cisplatin, oxaliplatin or carboplatin calls for the replacement of these therapeutic agents in clinical settings. We have previously identified a set of half sandwich-type osmium, ruthenium and iridium complexes with bidentate glycosyl heterocyclic ligands exerting specific cytostatic activity on cancer cells but not on non-transformed primary cells. The apolar nature of the complexes, conferred by large, apolar benzoyl protective groups on the hydroxyl groups of the carbohydrate moiety, was the main molecular feature to induce cytostasis. We exchanged the benzoyl protective groups to straight chain alkanoyl groups with varying length (3 to 7 carbon units) that increased the IC₅₀ value as compared to the benzoyl-protected complexes and rendered the complexes toxic. These results suggest a need for aromatic groups in the molecule. The pyridine moiety of the bidentate ligand was exchanged for a quinoline group to enlarge the apolar surface of the molecule. This modification decreased the IC₅₀ value of the complexes. The complexes containing [(η⁶-p-cymene)Ru(II)], [(η⁶-p-cymene)Os(II)] or [(η⁵-Cp*)Ir(III)] were biologically active unlike the complex containing [(η⁵-Cp*)Rh(III)]. The complexes with cytostatic activity were active on ovarian cancer (A2780, ID8), pancreatic adenocarcinoma (Capan2), sarcoma (Saos) and lymphoma cell lines (L428), but not on primary dermal fibroblasts and their activity was dependent on reactive oxygen species production. Importantly, these complexes were cytostatic on cisplatin-resistant A2780 ovarian cancer cells with similar IC₅₀ values as on cisplatin-sensitive A2780 cells. In addition, the quinoline-containing Ru and Os complexes and the short chain alkanoyl-modified complexes (C3 and C4) proved to be bacteriostatic in multiresistant Gram-positive Enterococcus and Staphylococcus aureus isolates. Hereby, we identified a set of complexes with submicromolar to low micromolar inhibitory constants against a wide range of cancer cells, including platinum resistant cells and against multiresistant Gram-positive bacteria.

Concomitant analyses of intratumoral microbiota and genomic features reveal distinct racial differences in breast cancer

Racial disparities are most accentuated among Black women as their lifetime risk of breast cancer incidence is lower than white and Asian women but their breast cancer related mortality is the highest among all races. Black women are more likely to develop triple-negative breast cancer at a younger age and harbor more aggressive tumors. In addition to tumor-centric alterations, tumor growth is also influenced by multiple other tumor microenvironment-related features, including resident immune cells and microbiota. Hence, in this study, we conduct concurrent genomic and metagenomic analyses, and uncover distinctive intratumoral microbial community compositions and tumor immune microenvironment-related traits in breast tumors from Asian, Black and white women. Interestingly, unique racially associated genomic nodes are found in the breast tumors from Asian, Black and white women. Examination of the cellular heterogeneity show differential enrichment of 11 out of 64 immune and stroma cell types in the breast tumors from different racial groups. In terms of microbial diversity, significant differences are revealed in alpha and beta-diversity measures. Intriguingly, potential race-specific microbial biomarkers of breast cancer are identified which significantly correlate with genes involved with tumor aggressiveness, angiogenesis, tumor cell migration and metastasis as well as oncogenic pathways-GLI and Notch. Investigating the metabolic features of intratumoral microbes, we find a significant differential enrichment of environmental information processing pathways, oncogenic pathways, and lipid metabolism pathways. Concomitantly investigating tumor-centric, tumor immune microenvironment-related and microbial alterations, our study provides a comprehensive understanding of racial disparities in breast cancer and warrants further exploration.

Sphingosine 1-phosphate receptor 2 promotes the onset and progression of non-alcoholic fatty liver disease-related hepatocellular carcinoma through the PI3K/AKT/mTOR pathway

PURPOSE

Recent studies have revealed an increase in the incidence rate of non-alcoholic fatty liver disease-related hepatocellular carcinoma (NAFLD-HCC). Furthermore, the association of Sphingosine 1-phosphate receptor 2 (S1PR2) with various types of tumours is identified, and the metabolism of conjugated bile acids (CBAs) performs an essential function in the onset and development of HCC. However, the association of CBA and S1PR2 with NAFLD-HCC is unclear.

METHODS

The relationship between the expression of S1PR2 and the prognosis of patients suffering from NAFLD-HCC was investigated by bioinformatics techniques. Subsequently, the relationship between S1PR2 and the biological behaviours of HCC cell lines Huh 7 and HepG2 was explored by conducting molecular biology assays. Additionally, several in vivo animal experiments were carried out for the elucidation of the biological impacts of S1PR2 inhibitors on HCC cells. Finally, We used Glycodeoxycholic acid (GCDA) of CBA to explore the biological effects of CBA on HCC cell and its potential mechanism.

RESULTS

High S1PR2 expression was linked to poor prognosis of the NAFLD-HCC patients. According to cellular assay results, S1PR2 expression could affect the proliferation, invasion, migration, and apoptosis of Huh 7 and HepG2 cells, and was closely associated with the G1/G2 phase of the cell cycle. The experiments conducted in the In vivo conditions revealed that the overexpression of S1PR2 accelerated the growth of subcutaneous tumours. In addition, JTE-013, an antagonist of S1PR2, effectively inhibited the migration and proliferation of HCC cells. Furthermore, the bioinformatics analysis highlighted a correlation between S1PR2 and the PI3K/AKT/mTOR pathway. GCDA administration further enhanced the expression levels of p-AKT, p-mTOR, VEGF, SGK1, and PKCα. Moreover, both the presence and absence of GCDA did not reveal any significant change in the levels of S1PR2, p-AKT, p-mTOR, VEGF, SGK1, and PKCα proteins under S1PR2 knockdown, indicating that CBA may regulates the PI3K/AKT/mTOR pathway by mediating S1PR2 expression.

CONCLUSION

S1PR2 is a potential prognostic biomarker in NAFLD-HCC. In addition, We used GCDA in CBAs to treat HCC cell and found that the expression of S1PR2 was significantly increased, and the expression of PI3K/AKT/mTOR signalling pathway-related signal molecules was also significantly enhanced, indicating that GCDA may activate PI3K/AKT/mTOR signalling pathway by up-regulating the expression of S1PR2, and finally affect the activity of hepatocellular carcinoma cells. S1PR2 can be a candidate therapeutic target for NAFLD-HCC. Collectively, the findings of this research offer novel perspectives on the prevention and treatment of NAFLD-HCC.

Understanding and harnessing triple-negative breast cancer-related microbiota in oncology

Bacterial inhabitants of the body have the potential to play a role in various stages of cancer initiation, progression, and treatment. These bacteria may be distal to the primary tumour, such as gut microbiota, or local to the tissue, before or after tumour growth. Breast cancer is well studied in this context. Amongst breast cancer types, Triple Negative Breast Cancer (TNBC) is more aggressive, has fewer treatment options than receptor-positive breast cancers, has an overall worse prognosis and higher rates of reoccurrence. Thus, an in-depth understanding of the bacterial influence on TNBC progression and treatment is of high value. In this regard, the Gut Microbiota (GM) can be involved in various stages of tumour progression. It may suppress or promote carcinogenesis through the release of carcinogenic metabolites, sustenance of proinflammatory environments and/or the promotion of epigenetic changes in our genome. It can also mediate metastasis and reoccurrence through interactions with the immune system and has been recently shown to influence chemo-, radio-, and immune-therapies. Furthermore, bacteria have also been found to reside in normal and malignant breast tissue. Several studies have now described the breast and breast tumour microbiome, with the tumour microbiota of TNBC having the least taxonomic diversity among all breast cancer types. Here, specific conditions of the tumour microenvironment (TME) - low O2, leaky vasculature and immune suppression - are supportive of tumour selective bacterial growth. This innate bacterial ability could enable their use as delivery agents for various therapeutics or as diagnostics. This review aims to examine the current knowledge on bacterial relevance to TNBC and potential uses while examining some of the remaining unanswered questions regarding mechanisms underpinning observed effects.

Elevated bile acid metabolism and microbiome are associated with suppressed cell proliferation and better survival in breast cancer

Bile acids are metabolized by the gut microbiome and are involved in fat absorption. Contrary to their carcinogenic role in gastrointestinal cancers, bile acids have been reported to inhibit cancer cell proliferation in breast cancer. The microbiome of breast cancer tissues may also influence cancer proliferation. We hypothesized that bile acid metabolism reflects its accumulation and is associated with certain microbiomes, breast cancer biology, and patient survival. Transcriptomic and clinicopathological information of a total of 6050 patients in three large open primary breast cancer cohorts (GSE96058, METABRIC, TCGA) and 16S rRNA gene sequence microbiome data of breast cancer tissues in TCGA were analyzed by high and low bile acid metabolism scores calculated by gene set variation analysis (GSVA). Breast cancers with high bile acid metabolism had a significantly improved survival across all three cohorts. Metabolic pathways related to the production and regulation of bile acids were consistently enriched in high bile acid metabolism groups across all cohorts. On the other hand, the low bile acid metabolism group was associated with higher Ki67 expression and Nottingham histological grade, as well as enrichment of cell proliferation-related gene sets. Intratumoral heterogeneity, homologous recombination deficiency, mutational load, activation of cancer immunity, and infiltration of anticancer immune cells were also higher in this group. Gammaretrovirus, Hymenobacter, Anaerococcus, and Collimonas were significantly more abundant in the high bile acid metabolism group compared to Lactobacillus, Ruegeria, and Marichromatium in the low metabolism group. Surprisingly, almost all Hallmark cell proliferation-associated gene sets were highly enriched in all three microorganisms that were abundant in the low bile acid metabolism group. In conclusion, microorganisms abundant in the breast tumor microenvironment with low bile acid metabolism are associated with aggressive cancer biology, including increased cell proliferation and poor survival.

Lithocholic acid inhibits gallbladder cancer proliferation through interfering glutaminase-mediated glutamine metabolism

Lithocholic acid (LCA), one of the most common metabolic products of bile acids (BAs), is originally synthesized in the liver, stored in the gallbladder, and released to the intestine, where it assists absorption of lipid-soluble nutrients. LCA has recently emerged as a powerful reagent to inhibit tumorigenesis; however, the anti-tumor activity and molecular mechanisms of LCA in gallbladder cancer (GBC) remain poorly acknowledged. Here, we analyzed serum levels of LCA in human GBC and found that LCA was significantly downregulated in these patients, and reduced LCA levels were associated with poor clinical outcomes. Treatment of xenografts with LCA impeded tumor growth. Furthermore, LCA treatment in GBC cell lines decreased glutaminase (GLS) expression, glutamine (Gln) consumption, and GSH/GSSG and NADPH/NADP⁺ ratios, leading to cellular ferroptosis. In contrast, GLS overexpression in tumor cells fully restored GBC proliferation and decreased ROS imbalance, thus suppressing ferroptosis. Our findings reveal that LCA functions as a tumor-suppressive factor in GBC by downregulating GLS-mediated glutamine metabolism and subsequently inducing ferroptosis. This study may offer a new therapeutic strategy tailored to improve the treatment of GBC.

The Bile Acid Membrane Receptor TGR5 in Cancer: Friend or Foe?

The G-protein-coupled bile acid receptor, Gpbar1 or TGR5, is characterized as a membrane receptor specifically activated by bile acids. A series of evidence shows that TGR5 induces protein kinase B (AKT), nuclear factor kappa-B (NF-κB), extracellular regulated protein kinases (ERK1/2), signal transducer and activator of transcription 3 (STAT3), cyclic adenosine monophosphate (cAMP), Ras homolog family member A (RhoA), exchange protein activated by cAMP (Epac), and transient receptor potential ankyrin subtype 1 protein (TRPA1) signaling pathways, thereby regulating proliferation, inflammation, adhesion, migration, insulin release, muscle relaxation, and cancer development. TGR5 is widely distributed in the brain, lung, heart, liver, spleen, pancreas, kidney, stomach, jejunum, ileum, colon, brown adipose tissue (BAT), white adipose tissue (WAT), and skeletal muscle. Several recent studies have demonstrated that TGR5 exerts inconsistent effects in different cancer cells upon activating via TGR5 agonists, such as INT-777, ursodeoxycholic acid (UDCA), and taurolithocholic acid (TLCA). In this review, we discuss both the ‘friend’ and ‘foe’ features of TGR5 by summarizing its tumor-suppressing and oncogenic functions and mechanisms.

Current and Emerging Methods for Ovarian Cancer Screening and Diagnostics: A Comprehensive Review

With a 5-year survival rate of less than 50%, ovarian high-grade serous carcinoma (HGSC) is one of the most highly aggressive gynecological malignancies affecting women today. The high mortality rate of HGSC is largely attributable to delays in diagnosis, as most patients remain undiagnosed until the late stages of -disease. There are currently no recommended screening tests for ovarian cancer and there thus remains an urgent need for new diagnostic methods, particularly those that can detect the disease at early stages when clinical intervention remains effective. While diagnostics for ovarian cancer share many of the same technical hurdles as for other cancer types, the low prevalence of the disease in the general population, coupled with a notable lack of sensitive and specific biomarkers, have made the development of a clinically useful screening strategy particularly challenging. Here, we present a detailed review of the overall landscape of ovarian cancer diagnostics, with emphasis on emerging methods that employ novel protein, genetic, epigenetic and imaging-based biomarkers and/or advanced diagnostic technologies for the noninvasive detection of HGSC, particularly in women at high risk due to germline mutations such as BRCA1/2. Lastly, we discuss the translational potential of these approaches for achieving a clinically implementable solution for screening and diagnostics of early-stage ovarian cancer as a means of ultimately improving patient outcomes in both the general and high-risk populations.

In vitro protoscolicidal effects of lithocholic acid on protoscoleces of Echinococcus granulosus and its mechanism

Surgery has been found to be the best choice of treatment for hydatidosis. However, leakage of cyst contents during surgery is the foremost reason for recurrence of hydatidosis. In this study, we investigated the in vitro efficacy of lithocholic acid (LCA) against Echinococcus granulosus protoscoleces. The protoscoleces were divided into a control group, an albendazole (ABZ) positive control group and LCA intervention groups at concentrations of 0.5, 1, 2, and 3 mmol/L and stained with 0.1% eosin for observation using an inverted microscope; the protoscolecal ultrastructure was examined with SEM and TEM; the activities of ROS, SOD, and caspase-3 were investigated using an ROS kit, SOD kit, and caspase-3 kit, respectively; the contents of HO-1 and NQO-1 were analyzed by enzyme-linked immunosorbent assay; and the expression level of cytochrome c (Ctyc) was analyzed by western blotting. Results: As the concentration of LCA increased, the survival rate of protoscoleces gradually decreased. The microstructure shows that the external shape and internal structure were gradually deformed and collapse. SOD, GSH, HO-1 and NQO-1 decreased more significantly in the 3 mmol/L LCA group. However, ROS levels gradually increased. LCA treatment for 3 days at all concentrations significantly increased caspase-3 activity and expression in a dose-dependent manner. LCA decreased the level of Ctyc protein in vitro. LCA demonstrated a parasiticidal effect on the protoscoleces of Echinococcus granulosus in vitro. LCA may induce apoptosis of E. granulosus protoscoleces by oxidative stress and mitochondrial pathways.

New Developments and Opportunities of Microbiota in Treating Breast Cancers

Despite the prevalence of breast cancer (BC), over half of BC cases are unrelated to known risk factors, which highlights the importance of uncovering more cancer-related factors. Currently, the microbiota has been proven to be a potent modulator of the tumor environment in BC, which regulates the immune balance in tumor-related networks. Through a large amount of data accumulation, the microbiota has shown many possibilities to reveal more insights into the development or control of BC. To expand the potential benefits of patients with BC, this study discusses the distribution profile and the effect mechanism of BC-related microbiota on tumors and further discusses its impact on different tumor therapies. Finally, we summarize the possibility of targeting microbiological therapies to improve BC treatment or in combination with other therapies.

The role of bile acids in carcinogenesis

Bile acids are soluble derivatives of cholesterol produced in the liver that subsequently undergo bacterial transformation yielding a diverse array of metabolites. The bulk of bile acid synthesis takes place in the liver yielding primary bile acids; however, other tissues have also the capacity to generate bile acids (e.g. ovaries). Hepatic bile acids are then transported to bile and are subsequently released into the intestines. In the large intestine, a fraction of primary bile acids is converted to secondary bile acids by gut bacteria. The majority of the intestinal bile acids undergo reuptake and return to the liver. A small fraction of secondary and primary bile acids remains in the circulation and exert receptor-mediated and pure chemical effects (e.g. acidic bile in oesophageal cancer) on cancer cells. In this review, we assess how changes to bile acid biosynthesis, bile acid flux and local bile acid concentration modulate the behavior of different cancers. Here, we present in-depth the involvement of bile acids in oesophageal, gastric, hepatocellular, pancreatic, colorectal, breast, prostate, ovarian cancer. Previous studies often used bile acids in supraphysiological concentration, sometimes in concentrations 1000 times higher than the highest reported tissue or serum concentrations likely eliciting unspecific effects, a practice that we advocate against in this review. Furthermore, we show that, although bile acids were classically considered as pro-carcinogenic agents (e.g. oesophageal cancer), the dogma that switch, as lower concentrations of bile acids that correspond to their serum or tissue reference concentration possess anticancer activity in a subset of cancers. Differences in the response of cancers to bile acids lie in the differential expression of bile acid receptors between cancers (e.g. FXR vs. TGR5). UDCA, a bile acid that is sold as a generic medication against cholestasis or biliary surge, and its conjugates were identified with almost purely anticancer features suggesting a possibility for drug repurposing. Taken together, bile acids were considered as tumor inducers or tumor promoter molecules; nevertheless, in certain cancers, like breast cancer, bile acids in their reference concentrations may act as tumor suppressors suggesting a Janus-faced nature of bile acids in carcinogenesis.

Late-Stage Glioma Is Associated with Deleterious Alteration of Gut Bacterial Metabolites in Mice

Brain-gut axis refers to the bidirectional functional connection between the brain and the gut, which sustains vital functions for vertebrates. This connection also underlies the gastrointestinal (GI) comorbidities associated with brain disorders. Using a mouse model of glioma, based on the orthotopic injection of GL261 cell line in syngeneic C57BL6 mice, we show that late-stage glioma is associated with GI functional alteration and with a shift in the level of some bacterial metabolites in the cecum. By performing cecal content transfer experiments, we further show that cancer-associated alteration in cecal metabolites is involved in end-stage disease progression. Antibiotic treatment results in a slight but significant delay in mice death and a shift in the proportion of myeloid cells in the brain tumor environment. This work rationally considers microbiota modulating strategies in the clinical management of patients with late-stage glioma.

Research Progress of Bile Acids in Cancer

Bile acids (BAs) were originally known as detergents to facilitate the digestion and absorption of lipids. And our current knowledge of BAs has been extended to potential carcinogenic or cancer suppressor factors due to constant research. In fact, BAs were regarded as a tumor promoters as early as the 1940s. Differential bile acid signals emitted by various bile acid profiles can produce distinct pathophysiological traits, thereby participating in the occurrence and development of tumors. Nevertheless, in recent years, more and more studies have noticed the value of BAs as therapeutic targets. And several studies have applied BAs as a therapeutic agent for various diseases including cancer. Based on the above evidence, we acknowledge that the role of BAs in cancer has yet to be exploited, although considerable efforts have been made to probe the functions of BAs. In this review, we describe the characteristics of BAs as a double-edged sword in cancer, hoping to provide references for future cancer treatments.

Reactive Oxygen Species Production Is Responsible for Antineoplastic Activity of Osmium, Ruthenium, Iridium and Rhodium Half-Sandwich Type Complexes with Bidentate Glycosyl Heterocyclic Ligands in Various Cancer Cell Models

Platinum complexes are used in chemotherapy, primarily as antineoplastic agents. In this study, we assessed the cytotoxic and cytostatic properties of a set of osmium(II), ruthenium(II), iridium(III) and rhodium(III) half-sandwich-type complexes with bidentate monosaccharide ligands. We identified 5 compounds with moderate to negligible acute cytotoxicity but with potent long-term cytostatic activity. These structure-activity relationship studies revealed that: (1) osmium(II) p-cymene complexes were active in all models, while rhodium(III) and iridium(III) Cp* complexes proved largely inactive; (2) the biological effect was influenced by the nature of the central azole ring of the ligands—1,2,3-triazole was the most effective, followed by 1,3,4-oxadiazole, while the isomeric 1,2,4-oxadiazole abolished the cytostatic activity; (3) we found a correlation between the hydrophobic character of the complexes and their cytostatic activity: compounds with O-benzoyl protective groups on the carbohydrate moiety were active, compared to O-deprotected ones. The best compound, an osmium(II) complex, had an IC₅₀ value of 0.70 µM. Furthermore, the steepness of the inhibitory curve of the active complexes suggested cooperative binding; cooperative molecules were better inhibitors than non-cooperative ones. The cytostatic activity of the active complexes was abolished by a lipid-soluble antioxidant, vitamin E, suggesting that oxidative stress plays a major role in the biological activity of the complexes. The complexes were active on ovarian cancer, pancreatic adenocarcinoma, osteosarcoma and Hodgkin’s lymphoma cells, but were inactive on primary, non-transformed human fibroblasts, indicating their applicability as potential anticancer agents.

The involvement of oncobiosis and bacterial metabolite signaling in metastasis formation in breast cancer

Breast cancer, the most frequent cancer in women, is characterized by pathological changes to the microbiome of breast tissue, the tumor, the gut, and the urinary tract. Changes to the microbiome are determined by the stage, grade, origin (NST/lobular), and receptor status of the tumor. This year is the 50th anniversary of when Hill and colleagues first showed that changes to the gut microbiome can support breast cancer growth, namely that the oncobiome can reactivate excreted estrogens. The currently available human and murine data suggest that oncobiosis is not a cause of breast cancer, but can support its growth. Furthermore, preexisting dysbiosis and the predisposition to cancer are transplantable. The breast’s and breast cancer’s inherent microbiome and the gut microbiome promote breast cancer growth by reactivating estrogens, rearranging cancer cell metabolism, bringing about a more inflammatory microenvironment, and reducing the number of tumor-infiltrating lymphocytes. Furthermore, the gut microbiome can produce cytostatic metabolites, the production of which decreases or blunts breast cancer. The role of oncobiosis in the urinary tract is largely uncharted. Oncobiosis in breast cancer supports invasion, metastasis, and recurrence by supporting cellular movement, epithelial-to-mesenchymal transition, cancer stem cell function, and diapedesis. Finally, the oncobiome can modify the pharmacokinetics of chemotherapeutic drugs. The microbiome provides novel leverage on breast cancer that should be exploited for better management of the disease.

The interaction between gut microbiome and anti-tumor drug therapy

A large number of symbiotic gut microbiome exists in the human gastrointestinal micro-ecosystem. The daily diet, lifestyle, and body constitution influence the type and quantity of gut microbiome in the body. Increasing evidence demonstrates that the gut microbiome can affect tumor development and progress. We discuss in this paper how the gut microbiome impacts tumor pathology through DNA damage, production of dietary and microbial metabolites, altered cellular signaling pathways, immune system suppression, and involvement in pro-inflammatory pathways changing gut microbiome composition. The gut microbiome acts on different types of the anti-tumor drug through bacterial translocation, immuno-modulation, metabolic modulation, enzymatic degradation, and reduction of microbial diversity. This article summarized the aforementioned by reviewing recent studies on the interaction among the gut microbiome, tumor development, and antitumor drugs.

Comparison of the Gut Microbiota in Patients with Benign and Malignant Breast Tumors: A Pilot Study

The microbiome plays diverse roles in many diseases and can potentially contribute to cancer development. Breast cancer is the most commonly diagnosed cancer in women worldwide. Thus, we investigated whether the gut microbiota differs between patients with breast carcinoma and those with benign tumors. The DNA of the fecal microbiota community was detected by Illumina sequencing and the taxonomy of 16S rRNA genes. The α-diversity and β-diversity analyses were used to determine richness and evenness of the gut microbiota. Gene function prediction of the microbiota in patients with benign and malignant carcinoma was performed using PICRUSt. There was no significant difference in the α-diversity between patients with benign and malignant tumors (P = 3.15e-1 for the Chao index and P = 3.1e-1 for the ACE index). The microbiota composition was different between the 2 groups, although no statistical difference was observed in β-diversity. Of the 31 different genera compared between the 2 groups, level of only Citrobacter was significantly higher in the malignant tumor group than that in benign tumor group. The metabolic pathways of the gut microbiome in the malignant tumor group were significantly different from those in benign tumor group. Furthermore, the study establishes the distinct richness of the gut microbiome in patients with breast cancer with different clinicopathological factors, including ER, PR, Ki-67 level, Her2 status, and tumor grade. These findings suggest that the gut microbiome may be useful for the diagnosis and treatment of malignant breast carcinoma.