The Gut Microbiota: A Potential Gateway to Improved Health Outcomes in Breast Cancer Treatment and Survivorship

The immunoregulatory role of gut microbiota in the incidence, progression, and therapy of breast cancer

Breast cancer (BrCa) is the most prevalent malignant tumor in women and one of the leading causes of female mortality. Its occurrence and progression are influenced by various factors, including genetics, environment, lifestyle, and hormones. In recent years, the gut microbiota has been identified as a significant factor affecting BrCa. The gut microbiota refers to the collective population of various microorganisms in the human gastrointestinal tract. Gut microbiota is closely associated with human health and disease development, participating in crucial physiological functions such as digestion, metabolism, immune response, and neural regulation. It has been found to influence the occurrence and treatment of BrCa through a variety of mechanisms. This article aims to review the immunomodulatory role of the gut microbiota in the development and treatment of BrCa.

Role of Gut Microbe Composition in Psychosocial Symptom Response to Exercise Training in Breast Cancer Survivors (ROME) study: protocol for a randomised controlled trial

INTRODUCTION

Breast cancer survivors have an increased risk for chronic fatigue and altered gut microbiota composition, both with negative health and quality of life affects. Exercise modestly improves fatigue and is linked to gut microbial diversity and production of beneficial metabolites. Studies suggest that gut microbiota composition is a potential mechanism underlying fatigue response to exercise. Randomised controlled trials testing the effects of exercise on the gut microbiome are limited and there is a scarcity of findings specific to breast cancer survivors. The objective of this study is to determine if fitness-related modifications to gut microbiota occur and, if so, mediate the effects of aerobic exercise on fatigue response.

METHODS AND ANALYSIS

The research is a randomised controlled trial among breast cancer survivors aged 18-74 with fatigue. The primary aim is to determine the effects of aerobic exercise training compared with an attention control on gut microbiota composition. The secondary study aims are to test if exercise training (1) affects the gut microbiota composition directly and/or indirectly through inflammation (serum cytokines), autonomic nervous system (heart rate variability) or hypothalamic-pituitary-adrenal axis mediators (hair cortisol assays), and (2) effects on fatigue are direct and/or indirect through changes in the gut microbiota composition. All participants receive a standardised controlled diet. Assessments occur at baseline, 5 weeks, 10 weeks and 15 weeks (5 weeks post intervention completion). Faecal samples collect the gut microbiome and 16S gene sequencing will identify the microbiome. Fatigue is measured by a 13-item multidimensional fatigue scale.

ETHICS AND DISSEMINATION

The University of Alabama at Birmingham Institutional Review Board (IRB) approved this study on 15 May 2019, UAB IRB#30000320. A Data and Safety Monitoring Board convenes annually or more often if indicated. Findings will be disseminated in peer-reviewed journals and conference presentations.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov, NCT04088708.

Therapeutic potential of LINS01 histamine H3 receptor antagonists as antineoplastic agents for triple negative breast cancer

The aims of this work were to evaluate the expression of histamine H3 receptor (H3R) in triple negative breast cancer (TNBC) samples and to investigate the antitumoral efficacy and safety of the LINS01 series of H3R antagonists, through in silico, in vitro, and in vivo approaches. Antitumor activity of LINS01009, LINS01010, LINS01022, LINS01023 was assayed in vitro in 4T1 and MDA-MB-231 TNBC cells (0.01-100 μM), and in vivo in 4T1 tumors orthotopically established in BALB/c mice (1 or 20 mg/kg). Additionally, H3R expression was assessed in 50 human TNBC samples. We have described a higher H3R mRNA expression in basal-like/TNBC tumors vs. matched normal tissue using TCGA Pan-Cancer Atlas data, and a higher H3R expression in human tumor samples vs. peritumoral tissue evidenced by immunohistochemistry associated with poorer survival. Furthermore, while all the essayed compounds showed antitumoral properties, LINS01022 and LINS01023 exhibited the most potent antiproliferative effects by: i) inducing cell apoptosis and suppressing cell migration in 4T1 and MDA-MB-231 TNBC cells, and ii) inhibiting cell growth in paclitaxel-resistant 4T1 cells (potentiating the paclitaxel antiproliferative effect). Moreover, 20 mg/kg LINS01022 reduced tumor size in 4T1 tumor-bearing mice, exhibiting a safe toxicological profile and potential for druggability estimated by ADME calculations. We conclude that the H3R is involved in the regulation of TNBC progression, offering promising therapeutic potential for the novel LINS01 series of H3R antagonists.

Stachydrine represses the proliferation and enhances cell cycle arrest and apoptosis of breast cancer cells via PLA2G2A/DCN axis

Considering the therapeutic efficacy of Stachydrine on breast cancer (BC), this study aims to decipher the relevant mechanism. The effects of Stachydrine on BC cell viability, proliferation and apoptosis were firstly investigated. Then, Bioinformatics was applied to sort out the candidate interacting with Stachydrine as well as its expression and downstream target in BC. Relative expressions of genes of interest as well as proliferation- and apoptosis-related factors in BC cells were quantified through quantitative reverse-transcription PCR and western blot as appropriate. As a result, Stachydrine inhibited the proliferation, down-regulated the expressions of proliferating cell nuclear antigen and CyclinD1, enhanced cell cycle arrest and apoptosis, and up-regulated the levels of Cleaved caspase-3 and Cleaved caspase-9 in BC cells. Phospholipase A2 Group IIA (PLA2G2A) was predicted as the candidate interacting with Stachydrine and to be lowly expressed in BC. PLA2G2A silencing reversed while PLA2G2A overexpression reinforced the effects of Stachydrine. Decorin (DCN) was the downstream target of PLA2G2A and also lowly expressed in BC. PLA2G2A silencing counteracted yet overexpressed PLA2G2A strengthened the promoting effects of Stachydrine on DCN level. Collectively, Stachydrine inhibits the growth of BC cells to promote cell cycle arrest and apoptosis via PLA2G2A/DCN axis.

Diet-driven microbiome changes and physical activity in cancer patients

Exploring the role of the gut microbiome in oncology is gaining more attention, mainly due to its ability to shape the immune system in cancer patients. A well-balanced microbial composition forms a symbiotic relationship with the host organism. Mounting evidence supports the potential of modifiable lifestyle factors, such as diet and physical activity, in restoring intestinal dysbiosis related to cancer development and treatment. In this Minireview, we describe the host-microbiome interplay following different dietary patterns, including a high-fat diet, fiber-rich diet, diet rich in rice and beans, Mediterranean diet, ketogenic diet, and physical activity in preclinical findings and clinical settings. According to the results, nutrition is a critical factor influencing the composition of gut microbial communities. Therefore, knowledge about the patient's nutritional status in pre-treatment and treatment becomes crucial for further management. A combination of individualized dietary habits and professional training plans might help to maintain gut homeostasis, potentially improving the response to anti-cancer therapy and the quality of life in cancer survivors. However, a deep understanding of underlying mechanisms and large clinical trials are needed to uncover clinically relevant correlations for personalized treatment approaches leading to better outcomes for cancer patients.

Unraveling the connections between gut microbiota, stress, and quality of life for holistic care in newly diagnosed breast cancer patients

There is little research about the stress, quality of life (QOL) and gut microbiota in newly diagnosed breast cancer patients. In this study addressing the dearth of research on stress, quality of life (QOL), and gut microbiota in newly diagnosed breast cancer patients, 82 individuals were prospectively observed. Utilizing the Functional Assessment of Chronic Illness Therapy (FACT)-Breast questionnaire to assess health-related quality of life (HRQOL) and the Distress Thermometer (DT) to gauge distress levels, the findings revealed a mean FACT-B score of 104.5, underscoring HRQOL's varied impact. Significantly, 53.7% reported moderate to severe distress, with a mean DT score of 4.43. Further exploration uncovered compelling links between distress levels, FACT-B domains, and microbial composition. Notably, Alcaligenaceae and Sutterella were more abundant in individuals with higher DT scores at the family and genus levels (p = 0.017), while Streptococcaceae at the family level and Streptococcus at the genus level were prevalent in those with lower DT scores (p = 0.028 and p = 0.023, respectively). This study illuminates the intricate interplay of stress, QOL, and gut microbiota in newly diagnosed breast cancer patients, offering valuable insights for potential interventions of biomarker or probiotics aimed at alleviating stress and enhancing QOL in this patient cohort.

Estrogens and the risk of breast cancer: A narrative review of literature

In female mammals, the development and regulation of the reproductive system and non-reproductive system are significantly influenced by estrogens (oestrogens). In addition, lipid metabolism is another physiological role of estrogens. Estrogens act through different types of receptors to introduce signals to the target cell by affecting many estrogen response elements. Breast cancer is considered mostly a hormone-dependent disease. Approximately 70% of breast cancers express progesterone receptors and/or estrogen receptors, and they are a good marker for cancer prognosis. This review will discuss estrogen metabolism and the interaction of estrogen metabolites with breast cancer. The carcinogenic role of estrogen is discussed in light of both conventional and atypical cancers susceptible to hormones, such as prostate, endometrial, and lung cancer, as we examine how estrogen contributes to the formation and activation of breast cancer. In addition, this review will discuss other factors that can be associated with estrogen-driven breast cancer.

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.

Control of Redox Homeostasis by Short-Chain Fatty Acids: Implications for the Prevention and Treatment of Breast Cancer

Breast cancer is the leading cause of death among women worldwide, and certain subtypes are highly aggressive and drug resistant. As oxidative stress is linked to the onset and progression of cancer, new alternative therapies, based on plant-derived compounds that activate signaling pathways involved in the maintenance of cellular redox homeostasis, have received increasing interest. Among the bioactive dietary compounds considered for cancer prevention and treatment are flavonoids, such as quercetin, carotenoids, such as lycopene, polyphenols, such as resveratrol and stilbenes, and isothiocyanates, such as sulforaphane. In healthy cells, these bioactive phytochemicals exhibit antioxidant, anti-apoptotic and anti-inflammatory properties through intracellular signaling pathways and epigenetic regulation. Short-chain fatty acids (SCFAs), produced by intestinal microbiota and obtained from the diet, also exhibit anti-inflammatory and anti-proliferative properties related to their redox signaling activity—and are thus key for cell homeostasis. There is evidence supporting an antioxidant role for SCFAs, mainly butyrate, as modulators of Nrf2-Keap1 signaling involving the inhibition of histone deacetylases (HDACs) and/or Nrf2 nuclear translocation. Incorporation of SCFAs in nutritional and pharmacological interventions changes the composition of the the intestinal microbiota, which has been shown to be relevant for cancer prevention and treatment. In this review, we focused on the antioxidant properties of SCFAs and their impact on cancer development and treatment, with special emphasis on breast cancer.

Physical Exercise and the Hallmarks of Breast Cancer: A Narrative Review

Growing evidence suggests that, among the different molecular/cellular pathophysiological mechanisms associated with cancer, there are 14 hallmarks that play a major role, including: (i) sustaining proliferative signaling, (ii) evading growth suppressors, (iii) activating invasion and metastasis, (iv) enabling replicative immortality, (v) inducing angiogenesis, (vi) resisting cell death, (vii) reprogramming energy metabolism, (viii) evading immune destruction, (ix) genome instability and mutations, (x) tumor-promoting inflammation, (xi) unlocking phenotypic plasticity, (xii) nonmutational epigenetic reprogramming, (xiii) polymorphic microbiomes, and (xiv) senescent cells. These hallmarks are also associated with the development of breast cancer, which represents the most prevalent tumor type in the world. The present narrative review aims to describe, for the first time, the effects of physical activity/exercise on these hallmarks. In summary, an active lifestyle, and particularly regular physical exercise, provides beneficial effects on all major hallmarks associated with breast cancer, and might therefore help to counteract the progression of the disease or its associated burden.

The gut microbiota in breast cancer development and treatment: The good, the bad, and the useful!

Regardless of the global progress in early diagnosis and novel therapeutic regimens, breast carcinoma poses a devastating threat, and the advances are somewhat marred by high mortality rates. Breast cancer risk prediction models based on the known risk factors are extremely useful, but a large number of breast cancers develop in women with no/low known risk. The gut microbiome exerts a profound impact on the host health and physiology and has emerged as a pivotal frontier in breast cancer pathogenesis. Progress in metagenomic analysis has enabled the identification of specific changes in the host microbial signature. In this review, we discuss the microbial and metabolomic changes associated with breast cancer initiation and metastatic progression. We summarize the bidirectional impact of various breast cancer-related therapies on gut microbiota and vice-versa. Finally, we discuss the strategies to modulate the gut microbiota toward a more favorable state that confers anticancer effects.

Effect of Chemotherapy on the Gut Microbiome of Breast Cancer Patients During the First Year of Treatment

INTRODUCTION

There is accumulating information of the effects of chemotherapy and weight changes on the gut microbiome of breast cancer patients.

METHODS

In this 1-year follow-up study, we investigated gut microbiome of 33 breast cancer patients who donated fecal samples at baseline and after completion of treatment. We compared alpha diversity and mean taxa abundance at baseline and absolute taxa abundance changes (final-baseline) by treatment (16 neoadjuvant [neoADJ], 13 adjuvant [ADJ], 4 no chemotherapy [noC]) and specific chemotherapy agent using Wilcoxon rank sum and negative binomial mixed model (NBMM) analysis.

RESULTS

All four gut alpha diversity measures changed in association with chemotherapy treatment; they increased in the neoADJ (+16.4% OTU p = 0.03; +51.6% Chao1 p = 0.03; +7.0% Shannon index p = 0.02; +11.0% PD whole tree p = 0.09) but not in the ADJ and noC group (ADJ+noC). The difference in Chao1 index change between groups was statistically significant (pneoADJ vs. ADJ+noC=0.04). Wilcoxon p values of 0.03-0.003 were observed for five taxa. In NBMM analysis, changes in taxa abundance differed (Bonferroni-adjusted p ≤ 0.0007) for two Bacteroidetes taxa (g_Alistipes, f_S24-7) and two Firmicutes taxa (g_Catenibacterium, g_Eubacterium). NBMM analysis results remained unchanged with adjustment for weight changes. Alpha diversity changes were also found by receipt of chemotherapy agents. Consistent increases in alpha diversity were observed among those treated with TCHP (OTU p = 0.009; Chao1 p = 0.02; Shannon p = 0.02; PD whole tree p = 0.05) but not AC, Taxol or Herceptin. Those treated with TCHP or Herceptin showed increases in Verrucomicrobia (g_Akkermansia) but decreases of Bacteroidetes(g_Alistipes); the differences in changes in taxa abundance were statistically significant.

CONCLUSION

Results from this pilot longitudinal study support an effect of chemotherapy, particularly neoADJ on the gut microbiome of breast cancer patients even after adjustment for weight changes. Further investigations are needed to confirm these findings in larger studies and with longer follow-up and to assess the impact of these microbiome changes on patient outcome.

The Bio-Diversity and the Role of Gut Microbiota in Postmenopausal Women with Luminal Breast Cancer Treated with Aromatase Inhibitors: An Observational Cohort Study

The interactions between aromatase inhibitors (AI) in breast cancer (BC) and gut microbiota (GM) have not been completely established yet. The aim of the study is to evaluate the bio-diversity of GM and the relationship between GM, inflammation and tumor-infiltrating lymphocytes (TILs) in postmenopausal women with BC during adjuvant AI treatment compared to women with disease relapse during or after one year of AI therapy ("endocrine-resistant"). We conducted a monocenter observational case-control study. Eighty-four women with BC (8 cases, 76 controls) were enrolled from 2019 to 2021. We observed a significant difference in the mean microbial abundance between the two groups for the taxonomic rank of order (p 0.035) and family (p 0.029); specifically, the case group showed higher diversity than the control group. Veillonella reached its maximum abundance in cases (p 0.022). Cytokine levels were compared among the groups created considering the TILs levels. We obtained a statistically significant difference (p 0.045) in IL-17 levels among the groups, with patients with low TILs levels showing a higher median value for IL-17 (0.15 vs. 0.08 pg/mL). Further studies about the bio-diversity in women with BC may lead to the development of new biomarkers and targeted interventions.

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.

Characteristics of the Gut Bacterial Composition in People of Different Nationalities and Religions

High-throughput sequencing has made it possible to extensively study the human gut microbiota. The links between the human gut microbiome and ethnicity, religion, and race remain rather poorly understood. In this review, data on the relationship between gut microbiota composition and the nationality of people and their religion were generalized. The unique gut microbiome of a healthy European (including Slavic nationality) is characterized by the dominance of the phyla Firmicutes, Bacteroidota, Actinobacteria, Proteobacteria, Fusobacteria, and Verrucomicrobia. Among the African population, the typical members of the microbiota are Bacteroides and Prevotella. The gut microbiome of Asians is very diverse and rich in members of the genera Prevotella, Bacteroides Lactobacillus, Faecalibacterium, Ruminococcus, Subdoligranulum, Coprococcus, Collinsella, Megasphaera, Bifidobacterium, and Phascolarctobacterium. Among Buddhists and Muslims, the Prevotella enterotype is characteristic of the gut microbiome, while other representatives of religions, including Christians, have the Bacteroides enterotype. Most likely, the gut microbiota of people of different nationalities and religions are influenced by food preferences. The review also considers the influences of pathologies such as obesity, Crohn’s disease, cancer, diabetes, etc., on the bacterial composition of the guts of people of different nationalities.

Modulating Microbiota as a New Strategy for Breast Cancer Prevention and Treatment

Breast cancer (BC) is the most common cancer in women in the United States. There has been an increasing incidence and decreasing mortality rate of BC cases over the past several decades. Many risk factors are associated with BC, such as diet, aging, personal and family history, obesity, and some environmental factors. Recent studies have shown that healthy individuals and BC patients have different microbiota composition, indicating that microbiome is a new risk factor for BC. Gut and breast microbiota alterations are associated with BC prognosis. This review will evaluate altered microbiota populations in gut, breast tissue, and milk of BC patients, as well as mechanisms of interactions between microbiota modulation and BC. Probiotics and prebiotics are commercially available dietary supplements to alleviate side-effects of cancer therapies. They also shape the population of human gut microbiome. This review evaluates novel means of modulating microbiota by nutritional treatment with probiotics and prebiotics as emerging and promising strategies for prevention and treatment of BC. The mechanistic role of probiotic and prebiotics partially depend on alterations in estrogen metabolism, systematic immune regulation, and epigenetics regulation.

Nano-Based Theranostic Platforms for Breast Cancer: A Review of Latest Advancements

Breast cancer (BC) is a highly metastatic multifactorial disease with various histological and molecular subtypes. Due to recent advancements, the mortality rate in BC has improved over the past five decades. Detection and treatment of many cancers are now possible due to the application of nanomedicine in clinical practice. Nanomedicine products such as Doxil^® and Abraxane^® have already been extensively used for BC adjuvant therapy with favorable clinical outcomes. However, these products were designed initially for generic anticancer purposes and not specifically for BC treatment. With a better understanding of the molecular biology of BC, several novel and promising nanotherapeutic strategies and devices have been developed in recent years. In this context, multi-functionalized nanostructures are becoming potential carriers for enhanced chemotherapy in BC patients. To design these nanostructures, a wide range of materials, such as proteins, lipids, polymers, and hybrid materials, can be used and tailored for specific purposes against BC. Selective targeting of BC cells results in the activation of programmed cell death in BC cells and can be considered a promising strategy for managing triple-negative BC. Currently, conventional BC screening methods such as mammography, digital breast tomosynthesis (DBT), ultrasonography, and magnetic resonance imaging (MRI) are either costly or expose the user to hazardous radiation that could harm them. Therefore, there is a need for such analytical techniques for detecting BC that are highly selective and sensitive, have a very low detection limit, are durable, biocompatible, and reproducible. In detecting BC biomarkers, nanostructures are used alone or in conjunction with numerous molecules. This review intends to highlight the recent advances in nanomedicine in BC treatment and diagnosis, emphasizing the targeting of BC cells that overexpress receptors of epidermal growth factors. Researchers may gain insight from these strategies to design and develop more tailored nanomedicine for BC to achieve further improvements in cancer specificity, antitumorigenic effects, anti-metastasis effects, and drug resistance reversal effects.

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 Chemo-Gut Pilot Study: Associations between Gut Microbiota, Gastrointestinal Symptoms, and Psychosocial Health Outcomes in a Cross-Sectional Sample of Young Adult Cancer Survivors

Chemotherapy adversely affects the gut microbiota, inducing dysbiosis, and negatively impacts gastrointestinal (GI) and psychosocial health during treatment, but little is known about the long-term effects or how these factors are related. Methods: This cross-sectional pilot study investigated the effects of chemotherapy on the gut microbiota, GI symptoms, and psychosocial outcomes in cancer survivors aged 18−39 years old, compared to healthy controls. Gut microbial diversity and composition were assessed from stool samples using 16S rRNA gene sequencing. Results: Survivors (n = 17) and healthy controls (n = 18) participated. Mean age at diagnosis was 31 years (±5.3). Mean time off treatment was 16.9 months (±16.4). Survivors had more severe GI symptoms, poorer psychosocial health, and increased relative abundance of Selenomondales, Veilloneliaceae, and Intestinibacter. In survivors, Lachnospiraceae, Ruminococcaceae and Intestinibacter correlated with psychosocial symptoms, while diarrhea correlated positively with Lachnospiraceae. Results are statistically significant. Survivors ≤6 months post-treatment had lower alpha diversity than survivors >6 months post-treatment (p = 0.04) and controls (p = 0.19). Conclusion: This small exploratory study demonstrates potential long-term gut microbial dysbiosis in cancer survivors, which may be associated with psychosocial symptoms. Larger trials concurrently and longitudinally examining gut microbiota, GI symptoms, and psychosocial outcomes are needed.

The gut connection: Intestinal permeability as a pathway from breast cancer survivors' relationship satisfaction to inflammation across treatment

BACKGROUND

Breast cancer survivors are prone to weakened gut barriers, allowing bacteria to migrate into the blood stream. Gut permeability fuels inflammation, which, among survivors, can elevate risk for comorbid disease development, cancer recurrence, and a poor quality of life; however, survivors' satisfying relationships can provide health benefits. This longitudinal study used a conceptual model addressing how intimate relationships is associated with health through changes in gut permeability and inflammation.

METHOD

Breast cancer survivors (n = 139, stages 0-IIIC) completed a baseline visit before treatment and two follow-up visits 6 and 18 months after treatment ended. Women who had an abnormal breast cancer test followed by a benign diagnosis completed visits within a comparable timeframe (noncancer patient controls; n = 69). All women completed questionnaires assessing their relationship satisfaction and provided blood samples to assess two bacterial endotoxin biomarkers, lipopolysaccharide-binding protein (LBP) and soluble CD14 (sCD14), as well as C-reactive protein (CRP) and interleukin 6 (IL-6).

RESULTS

Within-person multilevel mediation analyses showed that when a survivor's relationship satisfaction was higher than usual, her own LBP and LBP/sCD14 were lower, which was associated with lower than her own average CRP and IL-6 (95% CIs [-0.0104, -0.0002]). IL-6 was also higher when older survivors, but not younger survivors, experienced higher than usual intestinal permeability (p = .001). These effects of satisfying relationships held after accounting for cancer-related and behavioral factors. Post-hoc analyses showed LBP, sCD14, and LBP/sCD14 were associated with CRP for the cancer survivors, but only LBP and LBP/sCD14 were linked to CRP among the noncancer control patients.

CONCLUSION

The gut environment is a new promising candidate for understanding a relationship's long-term health impact, particularly among those with elevated health risks. Survivors may reap multiple physiological benefits from satisfying relationships.

Presence of human breast cancer xenograft changes the diurnal profile of amino acids in mice

Human xenografts are extremely useful models to study the biology of human cancers and the effects of novel potential therapies. Deregulation of metabolism, including changes in amino acids (AAs), is a common characteristic of many human neoplasms. Plasma AAs undergo daily variations, driven by circadian endogenous and exogenous factors. We compared AAs concentration in triple negative breast cancer MDA-MB-231 cells and MCF10A non-tumorigenic immortalized breast epithelial cells. We also measured plasma AAs in mice bearing xenograft MDA-MB-231 and compared their levels with non-tumor-bearing control animals over 24 h. In vitro studies revealed that most of AAs were significantly different in MDA-MB-231 cells when compared with MCF10A. Plasma concentrations of 15 AAs were higher in cancer cells, two were lower and four were observed to shift across 24 h. In the in vivo setting, analysis showed that 12 out of 20 AAs varied significantly between tumor-bearing and non-tumor bearing mice. Noticeably, these metabolites peaked in the dark phase in non-tumor bearing mice, which corresponds to the active time of these animals. Conversely, in tumor-bearing mice, the peak time occurred during the light phase. In the early period of the light phase, these AAs were significantly higher in tumor-bearing animals, yet significantly lower in the middle of the light phase when compared with controls. This pilot study highlights the importance of well controlled experiments in studies involving plasma AAs in human breast cancer xenografts, in addition to emphasizing the need for more precise examination of exometabolomic changes using multiple time points.

A straightforward access to trifluoromethylated natural products through late-stage functionalization

This review summarizes the applications of late-stage strategies in the direct trifluoromethylation of natural products in the past ten years, with particular emphasis on the reaction model of each method.

The Use of Prebiotic and Probiotic Interventions for Treating Gastrointestinal and Psychosocial Health Symptoms in Cancer Patients and Survivors: A Systematic Review

BACKGROUND

Cancer treatments can cause significant gastrointestinal (GI) health issues, and negatively affect patient's psychosocial health and quality of life (QOL). Novel, integrative strategies using prebiotics and probiotics have been explored for treating adverse cancer treatment-related side effects. We evaluated the current literature for interventions using prebiotics or probiotics specifically to treat GI and psychosocial health issues in cancer patients and survivors.

METHODS

Five databases (PubMed, MEDLINE (Ovid), CINHAL, PsychINFO, Web of Science) were searched for studies with prebiotic or probiotic interventions where GI and/or psychosocial health outcomes were measured in adult cancer patients and survivors, and published before September 12th 2021.

RESULTS

Twelve studies (N = 974 participants) meeting the inclusion criteria were identified (randomized controlled trials [n = 10], single-group pre-post studies [n = 2]). Ten studies were conducted with patients on active cancer treatment, and 2 studies treated patients after anti-cancer therapies. Three studies used prebiotics, 7 studies used probiotics, and 2 studies used a combination therapy. The most commonly used probiotic strains were from the Lactobacillus genus. There was minimal evidence for prebiotics to improve GI or psychosocial health. Probiotics were associated with significant improvements in abdominal pain (n = 2), gas/bloating (n = 2), and especially diarrhea (n = 5), and with improvements in anxiety (n = 1), depression (n = 1), fatigue (n = 1), and QOL (n = 2).

CONCLUSIONS

Studies specifically examining effects of prebiotics and probiotics on GI and psychosocial health outcomes are scarce. Probiotic intervention may improve some GI symptoms in cancer patients, and QOL in survivors. Controlled trials that consistently include GI and psychosocial health outcomes are needed.

Gut Microbiota: A Potential Target for Cancer Interventions

The gut microbiota plays a crucial role in many physiological processes in the human body. Dysbiosis can disrupt the intestinal barrier and alter metabolism and immune responses, leading to the development of diseases. Over the past few decades, evidence has accumulated linking changes in the composition of the gut microbiota to dozens of seemingly unrelated conditions, including cancer. Overall, the gut microbiota mainly affects the occurrence and development of cancer by damaging host DNA, forming and maintaining a pro-inflammatory environment, and affecting host immune responses. In addition, the gut microbiota can also affect the efficacy and toxicity of chemotherapy, radiotherapy, and immunotherapy. Scientists attempt to improve the efficacy and decrease the toxicity of these treatment modalities by fine-tuning the gut microbiota. The aim of this review is to assist researchers and clinicians in developing new strategies for the detection and treatment of tumors by providing the latest information on the intestinal microbiome and cancer, as well as exploring potential application prospects and mechanisms of action.

Microbiome Assisted Tumor Microenvironment: Emerging Target of Breast Cancer

The microbiome assisted tumor microenvironment (TME) supports the tumors by modulating multiple mechanisms. Recent studies reported that microbiome dysbiosis is the main culprit of immune suppressive phenotypes of TME. Further, it has been documented that immune suppressive stimulate metastatic phenotype in TME via modulating signaling pathways, cell differentiation, and innate immune response. This review aims at providing comprehensive developments in microbiome and breast TME interface. The combination of microbiome and breast cancer, breast TME and microbiome or microbial dysbiosis, microbiome and risk of breast cancer, microbiome and phytochemicals or anticancer drugs were as used keywords to retrieve literature from PubMed, Google scholar, Scopus, Web of Science from 2015 onwards. Based on the literature, we presented the impact of TME assisted microbiome dysbiosis and estrobolome in breast cancer risk, drug resistance, and antitumor immunity. We have discussed the influence of antibiotics on the breast microbiome. we also presented the possible dietary phytochemicals that target microbiome dysbiosis to restore the tumor suppression immune environment in breast TME. We presented the microbiome as a possible marker for breast cancer diagnosis. This study will help in the identification of microbiome as a novel target and diagnostic markers and phytochemicals and microbiome metabolites for breast cancer treatment.

Role of Gut Microbiota Dysbiosis in Breast Cancer and Novel Approaches in Prevention, Diagnosis, and Treatment

Breast cancer is the most common cause of cancer-related deaths in women. Breast cancer is still a major cause of morbidity and mortality among women despite all the available diagnostic and treatment modalities. The gut microbiota has drawn keen interest as an additional environmental risk factor in breast cancer, especially in sporadic cases. This article explores factors that disrupt the normal gut microbial composition and the role of gut microbial dysbiosis in the development of breast cancer. We finalized 40 relevant articles after searching Pubmed and Google Scholar using regular keywords and the Medical Subject Headings (MeSH) strategy. Gut microbiota dysbiosis has been shown to play a role in the development of breast cancer via estrogen-dependent mechanisms and non-estrogen-dependent mechanisms involving the production of microbial-derived metabolites, immune regulation, and effects on DNA. The gut microbiota influence estrogen metabolism hence estrogen levels. The metabolites that have demonstrated anticancer properties include lithocholic acid, butyrate, and cadaverine. New approaches targeting the gut microbiota have come up and may yield new advances in the prevention, diagnosis, and treatment of breast cancer. They include the use of prebiotics, probiotics, and hormone supplements to restore normobiosis in the prevention and treatment of breast cancer.

Gut microbiota homeostasis restoration may become a novel therapy for breast cancer

Breast cancer is the most diagnosed cancer in women. It significantly impairs a patient's physical and mental health. Gut microbiota comprise the bacteria residing in a host's gastrointestinal tract. Through studies over the last decade, we now know that alterations in the composition of the gut microbiome are associated with protection against colonization by pathogens and other diseases, such as diabetes and cancer. This review focuses on how gut microbiota can affect breast cancer development through estrogen activity and discusses the types of bacteria that may be involved in the onset and the progression of breast cancer. We also describe potential therapies to curtail the risk of breast cancer by restoring gut microbiota homeostasis and reducing systemic estrogen levels. This review will further explore the relationship between intestinal microbes and breast cancer and propose a method to treat breast cancer by improving intestinal microbes. We aimed at discovering new methods to prevent or treat BC by changing intestinal microorganisms.