Diet and gut microbiome interactions in gynecologic cancer

Therapeutic potential of microbiome modulation in reproductive cancers

The human microbiome, a complex ecosystem of microbial communities, plays a crucial role in physiological processes, and emerging research indicates a potential link between it and reproductive cancers. This connection highlights the significance of understanding the microbiome's influence on cancer development and treatment. A comprehensive review of current literature was conducted, focusing on studies that investigate the relationship between microbiome composition, reproductive cancer progression, and potential therapeutic approaches to modulate the microbiome. Evidence suggests that imbalances in the microbiome, known as dysbiosis, may contribute to the development and progression of reproductive cancers. Specific microbial populations have been associated with inflammatory responses, immune modulation, and even resistance to conventional therapies. Interventions such as probiotics, dietary modifications, and fecal microbiota transplantation have shown promise in restoring healthy microbiome function and improving cancer outcomes in pre-clinical models, with pilot studies in humans indicating potential benefits. This review explores the therapeutic potential of microbiome modulation in the management of reproductive cancers, discussing the mechanisms involved and the evidence supporting microbiome-targeted therapies. Future research is warranted to unravel the complex interactions between the microbiome and reproductive cancer pathophysiology, paving the way for innovative approaches.

Ketogenic diet and cancer: multidimensional exploration and research

The ketogenic diet (KD) has attracted attention in recent years for its potential anticancer effects. KD is a dietary structure of high fat, moderate protein, and extremely low carbohydrate content. Originally introduced as a treatment for epilepsy, KD has been widely applied in weight loss programs and the management of metabolic diseases. Previous studies have shown that KD can potentially inhibit the growth and spread of cancer by limiting energy supply to tumor cells, thereby inhibiting tumor angiogenesis, reducing oxidative stress in normal cells, and affecting cancer cell signaling and other processes. Moreover, KD has been shown to influence T-cell-mediated immune responses and inflammation by modulating the gut microbiota, enhance the efficacy of standard cancer treatments, and mitigate the complications of chemotherapy. However, controversies and uncertainties remain regarding the specific mechanisms and clinical effects of KD as an adjunctive therapy for cancer. Therefore, this review summarizes the existing research and explores the intricate relationships between KD and cancer treatment.

The effects of dietary fat on gut microbial composition and function in ovarian cancer

Objectives

The gut microbiome (GM) is pivotal in regulating inflammation, immune responses, and cancer progression. This study investigates the effects of a ketogenic diet (KD) and a high-fat/low-carbohydrate (HF/LC) diet on GM alterations and tumor growth in a syngeneic mouse model of high-grade serous ovarian cancer (EOC).

Methods

Thirty female C57BL/6J mice injected with KPCA cells were randomized into KD, HF/LC, and low-fat/high-carbohydrate (LF/HC) diet groups. Tumor growth was monitored with live, in vivo imaging. Stool samples were collected at the time of euthanasia and analyzed by 16SrRNA sequencing and shotgun metagenomic sequencing was performed to identify differential microbial taxonomic composition and metabolic function.

Results

Our findings revealed that KD and HF/LC diets significantly accelerated EOC tumor growth compared to the LF/HC diet in a xenograft model. GM diversity was markedly reduced in KD and HF/LC-fed mice, correlating with increased tumor growth, whereas LF/HC-fed mice showed higher GM diversity. Metagenomic analyses identified distinct alterations in microbial taxa including Bacteroides, Lachnospiracae bacterium, Bacterium_D16_50, and Enterococcus faecalis predominantly abundant in HF/LC-fed mice, Dubsiella_newyorkensis predominantly abundant in LF/HC-fed, and KD fed mice showing a higher abundance of Akkermansiaand Bacteroides. Functional pathways across diet groups indicated polyamine biosynthesis and fatty acid oxidation pathways were enriched in HF/LC-fed mice.

Conclusions

These results highlight the intricate relationship between diet, the gut microbiome, and tumor metabolism. The potential role of dietary interventions in cancer prevention and treatment warrants further investigation.

Environment and gynaecologic cancers

In the current era, environmental factors are well established as major causative agents for all cancers especially lung and breast cancer. We sought to review the current available literature on the topic pertaining to gynaecologic cancers. Although a few factors are well established in literature, others need more research to conclude.

The intestinal flora and nutritional status and immune function characteristics of obese colon cancer patients

BACKGROUND

The research aims to explore the characteristics of intestinal flora, nutritional status and immune function in patients with different types of obese colon cancer.

METHODS

A retrospective analysis is conducted on 64 cases of obese colon cancer diagnosed from June 2018 to January 2020. According to the histological staging of the cancer, they are classified into adenocarcinoma, adenosquamous carcinoma and undifferentiated carcinoma, with corresponding cases of 24, 22 and 18, respectively. The intestinal flora (Bifidobacterium, Lactobacillus, Enterococcus faecalis, Escherichia coli, and yeast), nutritional status (Hb, Alb, PA, TFN, and PNI), immune function (IgG, IgM, IgA, CD4+, CD8+, and CD4+/CD8+) are analyzed in the different groups of patients. Survival curves are evaluated by Kaplan-Meier method and log-rank test for tumour death, local recurrence, and distant metastasis.

RESULTS

There were no statistically significant differences in intestinal flora (Bifidobacterium, Lactobacillus, Enterococcus faecalis, Escherichia coli, and yeast), nutritional status (Hb, Alb, PA, TFN, and PNI) and immune function (IgG, IgM, IgA, CD4+, CD8+, and CD4+/CD8+) between different groups. There was a significant correlation between intestinal flora, nutritional status and immune function for all three. The survival curves of tumour death, local recurrence and distant metastasis in different groups of obese colon cancer patients were statistically significant. The tumor mortality rate, local recurrence, and distant metastasis rate in adenocarcinoma were 78.65%, 54.25% and 48.26% respectively.

CONCLUSION

There are differences in intestinal flora, nutritional status and immune function among different types of obese colon cancer patients, but adenocarcinoma has the least benefit in intestinal flora, poor nutritional status, and weakest immune function.

Harnessing probiotic foods: managing cancer through gut health

One of the greatest threats to global health is cancer. Probiotic foods have been shown to have therapeutic promise in the management of cancer, even though traditional treatments such as radiation therapy, chemotherapy, and surgery are still essential. The generation of anticarcinogenic compounds, immune system stimulation, and gut microbiota regulation are a few ways that probiotics when taken in sufficient quantities, might help health. The purpose of this review is to examine the therapeutic potential of probiotic foods in the management of cancer. Research suggests that certain strains of probiotics have anticancer effects by preventing the growth of cancer cells, triggering apoptosis, and reducing angiogenesis in new tumors. Probiotics have shown promise in mitigating treatment-related adverse effects, such as diarrhea, mucositis, and immunosuppression caused by chemotherapy, improving the general quality of life for cancer patients. However, there are several factors, such as patient-specific features, cancer subtype, and probiotic strain type and dosage, which affect how effective probiotic therapies are in managing cancer. More research is necessary to find the long-term safety and efficacy characteristics of probiotics as well as to clarify the best ways to incorporate them into current cancer treatment methods.

Graphical abstract

Graphical representation showing the role of probiotic foods in cancer management.

Effects of Combined Live Bifidobacterium, Lactobacillus, Enterococcus, and Bacillus Cereus Tablets on the Structure and Function of the Intestinal Flora in Rabbits Undergoing Hepatic Artery Infusion Chemotherapy

Few studies have explored the biological mechanism by which probiotics alleviate adverse reactions to chemotherapy drugs after local hepatic chemotherapy perfusion by regulating the intestinal flora. This study investigates the effects of Combined Live Bifidobacterium, Lactobacillus, Enterococcus, and Bacillus Cereus Tablets on the intestinal microbial structure and intestinal barrier function, as well as the potential mechanism in rabbits after local hepatic chemotherapy infusion. Eighteen New Zealand White rabbits were randomly divided into a control group, a hepatic local chemotherapy perfusion group, and a hepatic local chemotherapy perfusion + Combined Live Bifidobacterium, Lactobacillus, Enterococcus, and Bacillus Cereus Tablets group to assess the effects of Combined Live Bifidobacterium, Lactobacillus, Enterococcus, and Bacillus Cereus Tablets on the adverse reactions. The administration of Combined Live Bifidobacterium, Lactobacillus, Enterococcus, and Bacillus Cereus Tablets alleviated the intestinal flora disorder caused by local hepatic perfusion chemotherapy, promoted the growth of beneficial bacteria, and inhibited the growth of harmful bacteria. The Combined Live Bifidobacterium, Lactobacillus, Enterococcus, and Bacillus Cereus Tablets also reduced the levels of serum pro-inflammatory cytokines and liver injury factors induced by local hepatic perfusion chemotherapy. Our findings indicate that Combined Live Bifidobacterium, Lactobacillus, Enterococcus, and Bacillus Cereus Tablets can ameliorate the toxicity and side effects of chemotherapy by regulating intestinal flora, blocking pro-inflammatory cytokines, reducing liver injury factors, and repairing the intestinal barrier. Probiotics may be used as a potential alternative therapeutic strategy to prevent the adverse reactions caused by chemotherapy with local hepatic perfusion.

Impact of Lifestyle Interventions on Gynecologic Cancers: Beyond Diet and Exercise

A Lifestyle Medicine approach to compliment cancer care is less commonly researched or implemented for women with gynecologic cancers as compared to better funded malignancies such as breast, prostate, and colorectal. Yet, several gynecologic malignancies are linked to obesity, estrogen/metabolic signaling pathways, and altered tumor microenvironment which could benefit greatly from a lifestyle medicine program. Lifestyle medicine, an evidenced-based branch of science, has expanded to the prevention and treatment of disorders caused by lifestyle factors (including cancer). Modifiable lifestyle factors such as obesity, lack of physical activity/nutrient density, microbial dysbiosis, sleep disturbance, and chronic stressors contribute greatly to cancer morbidity and mortality worldwide. This overarching area of research is evolving with some subtopics in their infancy requiring further investigation. Modern tools have allowed for better understanding of mechanisms by which adiposity and inactivity affect tumor promoting signaling pathways as well as the local tumor environment. Through the evolving use of these sophisticated techniques, novel prognostic biomarkers have emerged to explore efficacy of pharmacologic and lifestyle interventions in cancer. This state-of-the-art review article appraises recent evidence for a lifestyle medicine approach, beyond diet and exercise, to optimize survivorship and quality of life for patients with gynecologic cancers and introduces the 8-week web-based comprehensive HEAL-GYN program.

Unlocking the Benefits of Fasting: A Review of its Impact on Various Biological Systems and Human Health

Fasting has gained significant attention in recent years for its potential health benefits in various body systems. This review aims to comprehensively examine the effects of fasting on human health, specifically focusing on its impact on different body's physiological systems. The cardiovascular system plays a vital role in maintaining overall health, and fasting has shown promising effects in improving cardiovascular health markers such as blood pressure, cholesterol levels, and triglyceride levels. Additionally, fasting has been suggested to enhance insulin sensitivity, promote weight loss, and improve metabolic health, thus offering potential benefits to individuals with diabetes and metabolic disorders. Furthermore, fasting can boost immune function, reduce inflammation, enhance autophagy, and support the body's defense against infections, cancer, and autoimmune diseases. Fasting has also demonstrated a positive effect on the brain and nervous system. It has been associated with neuroprotective properties, improving cognitive function, and reducing the risk of neurodegenerative diseases, besides the ability of increasing the lifespan. Hence, understanding the potential advantages of fasting can provide valuable insights for individuals and healthcare professionals alike in promoting health and wellbeing. The data presented here may have significant implications for the development of therapeutic approaches and interventions using fasting as a potential preventive and therapeutic strategy.

A multi-omics approach to understand the influence of polyphenols in ovarian cancer for precision nutrition: a mini-review

The impact of polyphenols in ovarian cancer is widely studied observing gene expression, epigenetic alterations, and molecular mechanisms based on new 'omics' technologies. Therefore, the combination of omics technologies with the use of phenolic compounds may represent a promising approach to precision nutrition in cancer. This article provides an updated review involving the current applications of high-throughput technologies in ovarian cancer, the role of dietary polyphenols and their mechanistic effects in ovarian cancer, and the current status and challenges of precision nutrition and their relationship with big data. High-throughput technologies in different omics science can provide relevant information from different facets for identifying biomarkers for diagnosis, prognosis, and selection of specific therapies for personalized treatment. Furthermore, the field of omics sciences can provide a better understanding of the role of polyphenols and their function as signaling molecules in the prevention and treatment of ovarian cancer. Although we observed an increase in the number of investigations, there are several approaches to data acquisition, analysis, and integration that still need to be improved, and the standardization of these practices still needs to be implemented in clinical trials.

The Female Reproductive Tract Microbiome and Cancerogenesis: A Review Story of Bacteria, Hormones, and Disease

The microbiota is the complex community of microorganisms that populate a particular environment in the human body, whereas the microbiome is defined by the entire habitat-microorganisms and their environment. The most abundant and, therefore, the most studied microbiome is that of the gastrointestinal tract. However, the microbiome of the female reproductive tract is an interesting research avenue, and this article explores its role in disease development. The vagina is the reproductive organ that hosts the largest number of bacteria, with a healthy profile represented mainly by Lactobacillus spp. On the other hand, the female upper reproductive tract (uterus, Fallopian tubes, ovaries) contains only a very small number of bacteria. Previously considered sterile, recent studies have shown the presence of a small microbiota here, but there are still debates on whether this is a physiologic or pathologic occurrence. Of particular note is that estrogen levels significantly influence the composition of the microbiota of the female reproductive tract. More and more studies show a link between the microbiome of the female reproductive tract and the development of gynecological cancers. This article reviews some of these findings.

Anti-cancer activity of human gastrointestinal bacteria

Malignant neoplasm is one of the most incurable diseases among inflammatory diseases. Researchers have been studying for decades to win over this lethal disease and provide the light of hope to humankind. The gastrointestinal bacteria of human hold a complex ecosystem and maintain homeostasis. One hundred trillion microbes are residing in the gastrointestinal tract of human. Disturbances in the microbiota of human's gastrointestinal tract can create immune response against inflammation and also can develop diseases, including cancer. The bacteria of the gastrointestinal tract of human can secrete a variety of metabolites and bioproducts which aid in the preservation of homeostasis in the host and gut. During pathogenic dysbiosis, on the other hand, numerous microbiota subpopulations may increase and create excessive levels of toxins, which can cause inflammation and cancer. Furthermore, the immune system of host and the epithelium cell can be influenced by gut microbiota. Probiotics, which are bacteria that live in the gut, have been protected against tumor formation. Probiotics are now studied to see if they can help fight dysbiosis in cancer patients undergoing chemotherapy or radiotherapy because of their capacity to maintain gut homeostasis. Countless numbers of gut bacteria have demonstrated anti-cancer efficiency in cancer treatment, prevention, and boosting the efficiency of immunotherapy. The review article has briefly explained the anti-cancer immunity of gut microbes and their application in treating a variety of cancer. This review paper also highlights the pre-clinical studies of probiotics against cancer and the completed and ongoing clinical trials on cancers with the two most common and highly effective probiotics Lactobacillus and Bacillus spp.

Differences in the microbial profiles of early stage endometrial cancers between Black and White women

OBJECTIVE

Black women suffer a higher mortality from endometrial cancer (EC) than White women. Potential biological causes for this disparity include a higher prevalence of obesity and more lethal histologic/molecular subtypes. We hypothesize that another biological factor driving this racial disparity could be the EC microbiome.

METHODS

Banked tumor specimens of postmenopausal, Black and White women undergoing hysterectomy for early stage endometrioid EC were identified. The microbiota of the tumors were characterized by bacterial 16S rRNA sequencing. The microbial component of endometrioid ECs in The Cancer Genome Atlas (TCGA) database were assessed for comparison.

RESULTS

95 early stage ECs were evaluated: 23 Black (24%) and 72 White (76%). Microbial diversity was increased (p < 0.001), and Firmicutes, Cyanobacteria and OD1 phyla abundance was higher in tumors from Black versus White women (p < 0.001). Genus level abundance of Dietzia and Geobacillus were found to be lower in tumors of obese Black versus obese White women (p < 0.001). Analysis of early stage ECs in TCGA found that microbial diversity was higher in ECs from Black versus White women (p < 0.05). When comparing ECs from obese Black versus obese White women, 5 bacteria distributions were distinct, with higher abundance of Lactobacillus acidophilus in ECs from Black women being the most striking difference. Similarly in TCGA, Dietzia and Geobacillus were more common in ECs from White women compared to Black.

CONCLUSION

Increased microbial diversity and the distinct microbial profiles between ECs of obese Black versus obese White women suggests that intra-tumoral bacteria may contribute to EC disparities and pathogenesis.

Gut Microbial Diversity in Female Patients With Invasive Mole and Choriocarcinoma and Its Differences Versus Healthy Controls

Objective

To investigate variation in gut microbiome in female patients with invasive mole (IM) and choriocarcinoma (CC) and compare it with healthy controls.

Methods

Fecal microbiome of 12 female patients with IM, 9 female patients with CC, and 24 healthy females were analyzed based on 16s rDNA sequencing. Alpha (α) diversity was evaluated using Shannon diversity index and Pielou evenness index, while beta (β) diversity was assessed using principle coordinate analysis (PCoA) of unweighted Unifrac distances. The potential functional changes of microbiomes were predicted using Tax4Fun. The relative abundance of microbial taxa was compared using Welch’s t test. The role of varied gut microbiota was analyzed via receiver operating characteristic (ROC) curve.

Results

The α diversity and β diversity were significantly different between IM patients and controls, but not between CC patients and controls. In addition, the abundance of cancer-related genes was significantly increased in IM and CC patients. Notably, a total of 19 families and 39 genera were found to have significant differences in bacterial abundance. ROC analysis indicated that Prevotella_7 may be a potential biomarker among IM, CC, and controls.

Conclusion

Our study demonstrated that the diversity and composition of gut microbiota among IM patients, CC patients, and healthy females were significantly different, which provides rationale for using gut microbiota as diagnostic markers and treatment targets, as well as for further study of gut microbiota in gestational trophoblastic neoplasia (GTN).

Microbes in gynecologic cancers: Causes or consequences and therapeutic potential

Gynecologic cancers, starting in the reproductive organs of females, include cancer of cervix, endometrium, ovary commonly and vagina and vulva rarely. The changes in the composition of microbiome in gut and vagina affect immune and metabolic signaling of the host cells resulting in chronic inflammation, angiogenesis, cellular proliferation, genome instability, epithelial barrier breach and metabolic dysregulation that may lead to the onset or aggravated progression of gynecologic cancers. While microbiome in gynecologic cancers is just at horizon, certain significant microbiome signature associations have been found. Cervical cancer is accompanied with high loads of human papillomavirus, Fusobacteria and Sneathia species; endometrial cancer is reported to have presence of Atopobium vaginae and Porphyromonas species and significantly elevated levels of Proteobacteria and Firmicutes phylum bacteria, with Chlamydia trachomatis, Lactobacillus and Mycobacterium reported in ovarian cancer. Balancing microbiome composition in gynecologic cancers has the potential to be used as a therapeutic target. For example, the Lactobacillus species may play an important role in blocking adhesions of incursive pathogens to vaginal epithelium by lowering the pH, producing bacteriocins and employing competitive exclusions. The optimum or personalized balance of the microbiota can be maintained using pre- and probiotics, and fecal microbiota transplantations loaded with specific bacteria. Current evidence strongly suggest that a healthy microbiome can train and trigger the body's immune response to attack various gynecologic cancers. Furthermore, microbiome modulations can potentially contribute to improvements in immuno-oncology therapies.

Diet-induced microbiome shifts of sympatric overwintering birds

Gut microbiota have a significant impact on host physiology and health, and host genetics and diet are considered as two important factors, but it is difficult to discriminate the influence of each single factor (host or diet) on gut microbiota under natural conditions. Moreover, current studies of avian microbiota mainly focus on domestic or captive birds, and it is still uncertain how host and diet take part in changing avian gut microbiota composition, diversity, and function in the wild. Here, high-throughput sequencing of 16S rRNA was used to identify the gut microbiota communities for sympatric wintering Great Bustards and Common Cranes at different diets. The results showed that 8.87% operational taxonomic units (OTUs) were shared among all sampling birds; in contrast, 39.43% of Kyoto Encyclopedia of Genes and Genomes (KEGG) functional pathways were common among all individuals, indicating the existence of gut microbiota conservatism both in microbiota structure and function. Microbiota abundance and diversity differed between Great Bustards and Common Cranes in a specific wintering site, and microbiota variation was detected for the same host species under two different sites, suggesting that the change of gut microbiota was induced by both host and diet. Furthermore, we found that changes of both microbial communities and functional pathways were larger between hosts than those between diets, which revealed that host might be the dominant factor determining microbiota characteristics and function, while diet further drove the divergence of gut microbiota. Gut microbiota functions appeared to be more conserved than bacterial community structure, indicating that different bacteria may function in a similar way, while microbiota OTU diversity might not be necessarily associated with functional diversity. With diet shifting, gut microbiota changed both in terms of microbial communities and functional pathways for the sympatric birds, which implies that avian habitats and their physiological microbiota would be influenced by different farmland management regimes. KEY POINTS: • Gut microbiota can be shaped by both diets and hosts in sympatric species. • Host was the dominant factor shaping the gut microbiota communities and functional pathways. • Gut microbiota were conservative both in structure and in function, but more conservative in function.

Gut Microbiota and Gynecological Cancers: A Summary of Pathogenetic Mechanisms and Future Directions

Over the past 20 years, important relationships between the microbiota and human health have emerged. A link between alterations of microbiota composition (dysbiosis) and cancer development has been recently demonstrated. In particular, the composition and the oncogenic role of intestinal bacterial flora has been extensively investigated in preclinical and clinical studies focusing on gastrointestinal tumors. Overall, the development of gastrointestinal tumors is favored by dysbiosis as it leads to depletion of antitumor substances (e.g., short-chain fatty acids) produced by healthy microbiota. Moreover, dysbiosis leads to alterations of the gut barrier, promotes a chronic inflammatory status through activation of toll-like receptors, and causes metabolic and hormonal dysregulations. However, the effects of these imbalances are not limited to the gastrointestinal tract and they can influence gynecological tumor carcinogenesis as well. The purpose of this Review is to provide a synthetic update about the mechanisms of interaction between gut microbiota and the female reproductive tract favoring the development of neoplasms. Furthermore, novel therapeutic approaches based on the modulation of microbiota and their role in gynecological oncology are discussed.

Exploring the Modulatory Effects of Gut Microbiota in Anti-Cancer Therapy

In the recent decade, gut microbiota has received growing interest due to its role in human health and disease. On the one hand, by utilizing the signaling pathways of the host and interacting with the immune system, the gut microbiota is able to maintain the homeostasis in human body. This important role is mainly modulated by the composition of microbiota, as a normal microbiota composition is responsible for maintaining the homeostasis of human body, while an altered microbiota profile could contribute to several pathogenic conditions and may further lead to oncogenesis and tumor progression. Moreover, recent insights have especially focused on the important role of gut microbiota in current anticancer therapies, including chemotherapy, radiotherapy, immunotherapy and surgery. Research findings have indicated a bidirectional interplay between gut microbiota and these therapeutic methods, in which the implementation of different therapeutic methods could lead to different alterations in gut microbiota, and the presence of gut microbiota could in turn contribute to different therapeutic responses. As a result, manipulating the gut microbiota to reduce the therapy-induced toxicity may provide an adjuvant therapy to achieve a better therapeutic outcome. Given the complex role of gut microbiota in cancer treatment, this review summarizes the interactions between gut microbiota and anticancer therapies, and demonstrates the current strategies for reshaping gut microbiota community, aiming to provide possibilities for finding an alternative approach to lower the damage and improve the efficacy of cancer therapy.