Gut Microbiome Associated with the Psychoneurological Symptom Cluster in Patients with Head and Neck Cancers

Psychological Factors Related to Treatment Outcomes in Head and Neck Cancer

BACKGROUND

Patients with head and neck cancer (HNC) often demonstrate stress, distress, anxiety, depression, and are at risk for suicide. These affect their quality of life (QoL) but less attention has been given to psychological variables that may impact response to treatment.

OBJECTIVES

This study aims to systematically review publications during 2013-2023 to collate evidence on the effects of psychological variables on HNC treatment outcomes.

METHODS

We searched Ovid Medline, PubMed, Scopus, and Web of Science for articles that examined psychological factors related to treatment outcomes in patients with HNC.

RESULTS

There were 29 studies (5 before treatment, 2 during, 17 after, and 5 covering the whole management trajectory) including 362,766 patients. The psychological factors were either behavioral (adjustment and coping strategy, unrealistic ideas, self-blame), cognitive (elevated risk of psychiatric co-comorbidity), or emotional (distress, depression, anxiety, nervousness, and fear of disfigurement and complications). It was found that there was a relationship between depression and decreased survival in patients with HNC. Pretreatment pain was an independent predictor of decreased survival in a large sample of patients. The distress level was approximately  54%, emotional problems ranged between 10 and 44%, while financial difficulties were identified in 54% of the patients. Sixty-nine percent of patients were reported to have used at least one cost-coping strategy within 6 months after treatment initiation. During post-treatment period, depression increased from 15% at the baseline to 29%, while the fear of recurrence was found among at least 35% of patients.

DISCUSSION AND CONCLUSION

Several psychological factors predict QoL and survival among HNC survivors. Distress encompasses depression and anxiety, and physical burden from HNC diagnosis and treatment. Routine screening and early interventions that target distress could improve HNC survivors' QoL. A systematic and standardized measurement approach for QoL is warranted to homogenize these findings and to understand the underlying relationships.

Gut microbiota and functional dyspepsia: a two-sample Mendelian randomization study

Background

Numerous studies have established that alterations in the gut microbiota (GM) constitute an embedded mechanism in functional dyspepsia (FD). However, the specific GM taxa implicated in the pathological process of FD have remained unclear.

Methods

A two-sample Mendelian randomization analysis was initially conducted to examine the causal relationships between GM and FD, utilizing GWAS data from the MiBioGen Consortium (18,340 cases) and FinnGenn (8,875 cases vs. 320,387 controls). The MR study primarily employed the inverse-variance weighted (IVW) method. Sensitivity analyses were performed to test for heterogeneity and pleiotropy. Single-nucleotide polymorphisms of causal GM taxa were mapped to genes, which were subsequently assessed for causal relationships with FD employing the same methodology.

Results

IVW results revealed that the genus Clostridium innocuum group (OR: 1.12, 95% CI: 1.02-1.24, P = 0.020) and genus Ruminiclostridium 9 were positively associated with FD risk (OR: 1.27, 95% CI: 1.03-1.57, P = 0.028), while the genus Lachnospiraceae FCS020 group tended to exert a negative effect on FD risk (OR = 0.84, 95% CI: 0.73-0.98, P = 0.023). Among GM-related genes, a notable association was observed between RSRC1 and increased FD risk (OR = 1.13, 95% CI: 1.07-1.20, P < 0.001). In sensitivity analyses, no significant pleiotropy or heterogeneity of the results was found.

Conclusions

This study furnished evidence for distinct effects of specific GM taxa on FD risk and hinted at a potential biological mechanism, thereby offering theoretical underpinning for future microbiotherapy of FD.

The association between the gut microbiome and fatigue in individuals living with cancer: a systematic review

PURPOSE

Fatigue is the most distressing symptom for individuals with cancer. While numerous studies have investigated biological pathways that could underlie the mechanism of fatigue, the cause of fatigue remains unclear. This review aimed to investigate the association between gut microbial composition and fatigue in individuals with cancer.

METHODS

Medline (PubMed), Embase (Elsevier), and CINAHL Complete (Ebscohost) were systemically searched on March 30, 2023, for articles investigating gut microbial composition (relative abundance, alpha diversity, and beta diversity) and fatigue in individuals with cancer; no limitations were placed on dates, participant age, nor cancer type/treatment.

RESULTS

Microbial composition in the form of relative abundance was correlated with fatigue in six of the seven articles. A high relative abundance of g_Ruminoccocus was observed in individuals with low fatigue. An elevated relative abundance of g_Escherichia and f_Enterobacteriaceae was associated with high fatigue. However, other associations between fatigue and relative abundance composition, such as with g_Bifidobacterium and g_Faecalibacterium, had conflicting results. For alpha diversity and fatigue, the findings were contradictory; the association between beta diversity and fatigue was unclear due to conflicting results.

CONCLUSIONS

Pro-inflammatory bacteria, such as f_Enterobacteriaceae, were more commonly associated with higher fatigue scores, while anti-inflammatory or short-chain fatty acid producing bacteria, such as g_Ruminoccocus, were linked with lower fatigue scores in individuals with cancer. The relationship between alpha and beta diversity and fatigue was inconclusive. Further investigation is needed to clarify whether gut microbial changes play a correlative or causal role in the development of fatigue in individuals with cancer.

Multi-omics analysis of the gut microbiome and metabolites associated with the psychoneurological symptom cluster in children with cancer receiving chemotherapy

BACKGROUND

Children with cancer receiving chemotherapy commonly report a cluster of psychoneurological symptoms (PNS), including pain, fatigue, anxiety, depression, and cognitive dysfunction. The role of the gut microbiome and its functional metabolites in PNS is rarely studied among children with cancer. This study investigated the associations between the gut microbiome-metabolome pathways and PNS in children with cancer across chemotherapy as compared to healthy children.

METHODS

A case-control study was conducted. Cancer cases were recruited from Children's Healthcare of Atlanta and healthy controls were recruited via flyers. Participants reported PNS using the Pediatric Patient-Reported Outcomes Measurement Information System. Data for cases were collected pre-cycle two chemotherapy (T0) and post-chemotherapy (T1), whereas data for healthy controls were collected once. Gut microbiome and its metabolites were measured using fecal specimens. Gut microbiome profiling was performed using 16S rRNA V4 sequencing, and metabolome was performed using an untargeted liquid chromatography-mass spectrometry approach. A multi-omics network integration program analyzed microbiome-metabolome pathways of PNS.

RESULTS

Cases (n = 21) and controls (n = 14) had mean ages of 13.2 and 13.1 years. For cases at T0, PNS were significantly associated with microbial genera (e.g., Ruminococcus, Megasphaera, and Prevotella), which were linked with carnitine shuttle (p = 0.0003), fatty acid metabolism (p = 0.001) and activation (p = 0.001), and tryptophan metabolism (p = 0.008). Megasphaera, clustered with aspartate and asparagine metabolism (p = 0.034), carnitine shuttle (p = 0.002), and tryptophan (p = 0.019), was associated with PNS for cases at T1. Gut bacteria with potential probiotic functions, along with fatty acid metabolism, tryptophan, and carnitine shuttle, were more clustered in cancer cases than the control network and this linkage with PNS needs further studies.

CONCLUSIONS

Using multi-omics approaches, this study indicated specific microbiome-metabolome pathways linked with PNS in children with cancer across chemotherapy. Due to limitations such as antibiotic use in cancer cases, these findings need to be further confirmed in a larger cohort.

The nerve cells in gastrointestinal cancers: from molecular mechanisms to clinical intervention

Gastrointestinal (GI) cancer is a formidable malignancy with significant morbidity and mortality rates. Recent studies have shed light on the complex interplay between the nervous system and the GI system, influencing various aspects of GI tumorigenesis, such as the malignance of cancer cells, the conformation of tumor microenvironment (TME), and the resistance to chemotherapies. The discussion in this review first focused on exploring the intricate details of the biological function of the nervous system in the development of the GI tract and the progression of tumors within it. Meanwhile, the cancer cell-originated feedback regulation on the nervous system is revealed to play a crucial role in the growth and development of nerve cells within tumor tissues. This interaction is vital for understanding the complex relationship between the nervous system and GI oncogenesis. Additionally, the study identified various components within the TME that possess a significant influence on the occurrence and progression of GI cancer, including microbiota, immune cells, and fibroblasts. Moreover, we highlighted the transformation relationship between non-neuronal cells and neuronal cells during GI cancer progression, inspiring the development of strategies for nervous system-guided anti-tumor drugs. By further elucidating the deep mechanism of various neuroregulatory signals and neuronal intervention, we underlined the potential of these targeted drugs translating into effective therapies for GI cancer treatment. In summary, this review provides an overview of the mechanisms of neuromodulation and explores potential therapeutic opportunities, providing insights into the understanding and management of GI cancers.

Associations of the gut microbiome with psychoneurological symptom cluster in women with gynecologic cancers: a longitudinal study

PURPOSE

The present study aimed to evaluate the associations between the gut microbiome and psychoneurological symptoms (PNS) cluster in women with gynecologic cancers over time.

METHODS

In this secondary data analysis, 19 women with cervical and endometrial cancers treated with radiotherapy were followed at pre-treatment, 6-8 weeks, and 6 months post-treatment. To measure symptoms, Functional Assessment of Cancer Therapy-General (FACT-G) and Patient Health Questionnaire-9 (PHQ-9) were used. An average Z score of at least three out of five symptoms was computed as the PNS cluster total score. Rectal swabs were also collected at the same time points and sequenced using 16S rRNA V4 regions. The Kruskal-Wallis and permutational multivariable analysis of variance tests were used to compare α- and β-diversity between patients with high and low PNS cluster. The linear discriminant analysis effect size (LEfSe) tested taxa differences between study groups. Also, the linear mixed-effect model was used to evaluate the association of the gut microbiome and the PNS cluster over cancer treatment.

RESULTS

The patients' mean age was 58 years, 47% Black, 52% single/divorced, and 66% had college or above education. Among the participants, 63% had endometrial cancer with stage I disease. There was a different taxonomy profile between patients with high and low PNS. Patients with high PNS had a lower α-diversity than those with low PNS (Shannon, p = 0.03, evenness, p = 0.03). The mixed effects model results showed that low α-diversity and abundance of Fusicatenibacter and Ruminococcus were associated with high PNS cluster over cancer treatment.

CONCLUSION

The association between the gut microbiome and PNS cluster suggest that the gut microbiota plays a role in developing the PNS cluster. Future larger studies are required to shed light on the gut microbiota role in symptom development in gynecologic cancer patients.

The role of bacteria and its derived biomaterials in cancer radiotherapy

Bacteria-mediated anti-tumor therapy has received widespread attention due to its natural tumor-targeting ability and specific immune-activation characteristics. It has made significant progress in breaking the limitations of monotherapy and effectively eradicating tumors, especially when combined with traditional therapy, such as radiotherapy. According to their different biological characteristics, bacteria and their derivatives can not only improve the sensitivity of tumor radiotherapy but also protect normal tissues. Moreover, genetically engineered bacteria and bacteria-based biomaterials have further expanded the scope of their applications in radiotherapy. In this review, we have summarized relevant researches on the application of bacteria and its derivatives in radiotherapy in recent years, expounding that the bacteria, bacterial derivatives and bacteria-based biomaterials can not only directly enhance radiotherapy but also improve the anti-tumor effect by improving the tumor microenvironment (TME) and immune effects. Furthermore, some probiotics can also protect normal tissues and organs such as intestines from radiation via anti-inflammatory, anti-oxidation and apoptosis inhibition. In conclusion, the prospect of bacteria in radiotherapy will be very extensive, but its biological safety and mechanism need to be further evaluated and studied.

Circulating short chain fatty acids and fatigue in patients with head and neck cancer: A longitudinal prospective study

Fatigue among patients with head and neck cancer (HNC) has been associated with higher inflammation. Short-chain fatty acids (SCFAs) have been shown to have anti-inflammatory and immunoregulatory effects. Therefore, this study aimed to examine the association between SCFAs and fatigue among patients with HNC undergoing treatment with radiotherapy with or without concurrent chemotherapy. Plasma SCFAs and the Multidimensional Fatigue Inventory-20 were collected prior to and one month after the completion of treatment in 59 HNC patients. The genome-wide gene expression profile was obtained from blood leukocytes prior to treatment. Lower butyrate concentrations were significantly associated with higher fatigue (p = 0.013) independent of time of assessment, controlling for covariates. A similar relationship was observed for iso/valerate (p = 0.025). Comparison of gene expression in individuals with the top and bottom 33% of butyrate or iso/valerate concentrations prior to radiotherapy revealed 1,088 and 881 significantly differentially expressed genes, respectively (raw p < 0.05). The top 10 Gene Ontology terms from the enrichment analyses revealed the involvement of pathways related to cytokines and lipid and fatty acid biosynthesis. These findings suggest that SCFAs may regulate inflammatory and immunometabolic responses and, thereby, reduce inflammatory-related symptoms, such as fatigue.

Associations of inflammation with neuropsychological symptom cluster in patients with Head and neck cancer: A longitudinal study

Purpose

Head and neck cancer (HNC) patients may experience multiple co-occurring neuropsychological symptoms (NPS) cluster, including fatigue, depression, pain, sleep disturbance, and cognitive impairment. While inflammation has been attributed as a key mechanism for some of these symptoms, its association with the NPS as a cluster of symptoms is unknown. Thus, the aim of this study was to examine the association between peripheral inflammation and NPS cluster among HNC patients over cancer treatment (radiotherapy with or without chemotherapy).

Methods

HNC patients were recruited and followed at pre-treatment, end of treatment, three months and one-year post-treatment. Plasma inflammatory markers, including C-reactive protein (CRP), tumor necrosis factor-alpha (TNFA), soluble tumor necrosis factor receptor-2 (sTNFR2), interleukin-1 beta (IL1-β), interleukin-6 (IL-6), interleukin-10 (IL-10), monocyte chemotactic protein-1 (MCP-1), and interleukin-1 receptor antagonist (IL-1RA) and patient-reported NPS cluster were collected at the 4 time points. Associations between inflammatory markers and the NPS cluster were analyzed using linear mixed-effects models and generalized estimating equations (GEE) models controlling covariates.

Results

147 HNC patients were eligible for analysis. 56% of the patients received chemoradiotherapy as treatment. The highest NPS cluster score was reported at the end of treatment, which gradually decreased over time. An increase in inflammatory markers including CRP, sTNFR2, IL-6 and IL-1RA was associated with higher continuous NPS cluster scores (p<0.001, p = 0.003, p<0.001, p<0.001; respectively). GEE further confirmed that patients with at least two moderate symptoms had elevated sTNFR2, IL-6, and IL-1RA (p = 0.017, p = 0.038, p = 0.008; respectively). Notably, this positive association between NPS cluster and inflammatory markers was still significant at one-year post-treatment for CRP (p = 0.001), sTNFR2 (p = 0.006), and IL-1RA (p = 0.043).

Conclusions

Most HNC patients experienced NPS clusters over time, especially immediately after the end of treatment. Elevated inflammation, as represented by inflammatory markers, was strongly associated with worse NPS cluster over time; this trend was also notable at one-year post-treatment. Our findings suggest that peripheral inflammation plays a pivotal role in the NPS cluster over cancer treatment, including long-term follow-ups. Interventions on reducing peripheral inflammation may contribute to alleviating the NPS cluster in cancer patients.

Gut microbiome and cancer implications: Potential opportunities for fermented foods

There is a critical opportunity to improve response to immunotherapies and overall cancer survivorship via dietary interventions targeted to modify the gut microbiome, and in turn, potentially enhance anti-cancer immunity. A promising dietary intervention is fermented foods, which may alter gut microbiome composition and, in turn, improve immunity. In this article, we summarize the state of the literature pertaining to the gut microbiome and response to immunotherapy and other cancer treatments, potential clinical implications of utilizing a fermented foods dietary approach to improve cancer treatment outcomes, and existing gaps in the literature regarding the implementation of fermented food interventions among individuals with cancer or with a history of cancer. This review synthesizes a compelling rationale across different disciplines to lay a roadmap for future fermented food dietary intervention research aimed at modulating the gut microbiome to reduce cancer burden.

The Cancer Genomic Integration Model for Symptom Science (CGIMSS): A Biopsychosocial Framework

Current nursing research has characterized symptom clusters and trajectories in individuals with breast cancer. The existing literature describes the relationship between symptoms and biological variables and the potential moderating effects of individual and social factors. The genomic profiling of breast cancer has also been an area of much recent research. Emerging evidence indicates that incorporating cancer genomics into symptom science research can aid in the prognostication of symptoms and elucidate targets for symptom management interventions. The aim of this paper is to outline a model to integrate cancer genomics into symptom science research, illustrated using breast cancer and psychoneurological (PN) symptoms as an example. We present a review of the current literature surrounding breast cancer genomics (specifically cancer genomic instability) and the biological underpinnings of the PN symptom cluster. Advances in both of these areas indicate that inflammation may serve as the bridge between cancer genomics and the PN symptom cluster. We also outline how the integration of cancer genomics into symptom science research synergizes with current research of individual and social factors in relation to symptoms. This model aims to provide a framework to guide future biopsychosocial symptom science research that can elucidate new predictive methods and new targets for intervention.

Sickness Symptoms in Kidney Transplant Recipients: A Scoping Review

Sickness symptoms (depressive symptoms, anxiety, and fatigue) are common among people with chronic illness, often presenting as a symptom cluster. Sickness symptoms persist in many patients with chronic kidney disease, even after kidney transplantation (KT); however, little is known about sickness symptom-induced burden in KT recipients. This scoping review synthesizes available evidence for sickness symptoms in KT recipients, including findings on symptom prevalence, predictors, outcomes, interrelationships, and clustering. Among 38 reviewed studies, none identified sickness symptoms as a cluster, but we observed interrelationships among the symptoms examined. Fatigue was the most prevalent sickness symptom, followed by anxiety and depressive symptoms. Predictors of these symptoms included demographic, clinical, and psychosocial factors, and health-related quality of life was the most researched outcome. Future research should use common data elements to phenotype sickness symptoms, include biological markers, and employ sophisticated statistical methods to identify potential clustering of sickness symptoms in KT recipients.

A Pilot Study of the Gut Microbiota Associated With Depressive Symptoms and Sleep Disturbance Among Chinese and Korean Immigrants in the United States

CONTEXT

Depression is prevalent among Asian Americans (AsA) during the COVID-19 pandemic, and depression often leads to sleep disturbance in this population. The gut microbiota (GM) plays a critical role in mental health and sleep quality, and the composition of the GM is largely unknown among AsA.

OBJECTIVES

Examine associations of the GM with depressive symptoms and sleep disturbance among Chinese and Korean American immigrants.

METHODS

Depressive symptoms (PROMIS Short Form-Depression) and sleep quality (Pittsburgh Sleep Quality Index [PSQI]) were collected via surveys. PROMIS measure T-score > 55 indicates positive depressive symptoms, and a total PSQI score > 5 indicates sleep disturbance. 16S rRNA V3-V4 gene regions were sequenced from fecal specimens to measure GM. Permutational multivariate analysis of variance and linear discriminant analysis effect size were applied to examine associations of the GM with symptoms.

RESULTS

Among 20 participants, 55% (n = 11) reported depressive symptoms and 35% (n = 7) reported sleep disturbance. A higher α-diversity was marginally associated with lower depressive symptoms: Chao1 (r = -0.39, p = 0.09) and Shannon index (r = -0.41, p = 0.08); β-diversity distinguished participants between categories of depressive symptoms (weighted UniFrac, p=0.04) or sleep disturbance (Jaccard, p=0.05). Those with depressive symptoms showed a higher abundance of Actinobacteria, while those without depressive symptoms had a higher abundance of Bacteroidetes. No significant taxa were identified for sleep disturbance.

CONCLUSIONS

Gut microbial diversity showed promising associations with depressive symptoms and sleep disturbance among Chinese and Korean immigrants. Specific taxa were identified as associated with depressive symptoms. Future studies with a larger sample size are warranted to confirm our findings.

Skin Microbiome and Treatment-Related Skin Toxicities in Patients With Cancer: A Mini-Review

The human skin hosts millions of bacteria, fungi, archaea, and viruses. These skin microbes play a crucial role in human immunological and physiological functions, as well as the development of skin diseases, including cancer when the balance between skin commensals and pathogens is interrupted. Due to the linkages between inflammation processes and skin microbes, and viral links to skin cancer, new theories have supported the role a dysbiotic skin microbiome plays in the development of cancer and cancer treatment-related skin toxicities. This review focuses on the skin microbiome and its role in cancer treatment-related skin toxicities, particularly from chemotherapy, radiation therapy, and immunotherapy. The current literature found changes in the diversity and abundance of the skin microbiome during cancer treatments such as radiation therapy, including lower diversity of the skin microbiome, an increased Proteobacteria/Firmicutes ratio, and a higher abundance of pathogenic Staphylococcus aureus. These changes may be associated with the development and severity of treatment-related skin toxicities, such as acute radiation dermatitis, hand-foot syndrome in chemotherapy, and immunotherapy-induced rash. Several clinical guidelines have issued potential interventions (e.g., use of topical corticosteroids, phototherapy, and non-pharmaceutical skin care products) to prevent and treat skin toxicities. The effectiveness of these promising interventions in alleviating treatment-related skin toxicities should be further tested among cancer patients.

Metabolic Pathways Associated With Psychoneurological Symptoms in Children With Cancer Receiving Chemotherapy

CONTEXT

Children with cancer undergoing chemotherapy experience a cluster of psychoneurological symptoms (PNS), including pain, fatigue, anxiety, and depressive symptoms. Metabolomics is promising to differentiate metabolic pathways associated with the PNS cluster.

OBJECTIVES

Identify metabolic pathways associated with the PNS cluster in children with cancer before and after chemotherapy.

METHODS

Pain, fatigue, anxiety, and depressive symptoms were assessed using the Pediatric PROMIS scales. T-scores were computed and divided dichotomously by a cutoff point of 50; the PNS cluster was a sum of the four symptoms ranging from 0 (all T-scores <50) to 4 (all T-scores ≥50). Serum metabolites were processed using liquid chromatography mass-spectrometry untargeted metabolomics approach. Linear regression models examined metabolites associated with the PNS cluster. Metabolic pathway enrichment analysis was performed.

RESULTS

Participant demographics (n = 40) were 55% female, 60% white, 62.5% aged 13-19 years, and 62.5% diagnoses of Hodgkin's lymphoma and B-cell acute lymphocytic leukemia. Among 9276 unique metabolic features, 454 were associated with pain, 281 with fatigue, 596 with anxiety, 551 with depressive symptoms, and 300 with the PNS cluster across one chemotherapy cycle. Fatty acids pathways were associated with pain: de novo fatty acid biosynthesis (p < .001), fatty acid metabolism (p = .001), fatty acid activation (p = .004), and omega-3 fatty acid metabolism (p = .009). Tryptophan amino acid pathway was associated with fatigue (p < .001), anxiety (p = .015), and the PNS cluster (p = .037). Carnitine shuttle was associated with the PNS cluster (p = .015).

CONCLUSION

Fatty acids and amino acids pathways were associated with PNS in children undergoing chemotherapy. These findings require further investigation in a larger sample.

Microbiomics Revealed the Disturbance of Intestinal Balance in Rabbits with Diarrhea Caused by Stopping the Use of an Antibiotic Diet

The harmful effects of diarrhea on the growth performance of rabbits have been well documented, but the details of the potential mechanism of intestinal diarrhea when antibiotics are stopped are still unclear. Here, PacBio sequencing technology was used to sequence the full length 16S rRNA gene of the microbiota of intestinal content samples, in order to characterize the bacterial communities in the small intestine (duodenum and jejunum) and large intestine (colon and cecum) in normal Hyplus rabbits and those with diarrhea. The histopathological examination showed that intestinal necrosis occurred in different degrees in the diarrhea group, and that the mucosal epithelium was shed and necrotic, forming erosion, and the clinical manifestation was necrosis. However, the intestinal tissue structure of the normal group was normal. The results revealed that there were significant differences in bacterial communities and structure between the diarrhea and normal groups of four intestinal segments (p < 0.05). In general, 16 bacterial phyla, 144 bacterial genera and 22 metabolic pathways were identified in the two groups. Tax4Fun functional prediction analysis showed that KEGG related to amino acid metabolism and energy metabolism was enriched in the large intestines of rabbits with diarrhea, whereas lipid metabolism was more abundant in the small intestine of rabbits with diarrhea. In conclusion, the change in the relative abundance of the identified dominant microbiota, which could deplete key anti-inflammatory metabolites and lead to bacterial imbalance and diarrhea, resulted in diarrhea in Hyplus rabbits that stopped using antibiotics.

Exploring the links among inflammation and gut microbiome with psychoneurological symptoms and gastrointestinal toxicities in gynecologic cancers: a systematic review

INTRODUCTION

Emerging evidence highlights the roles the gut microbiome and the immune system, integral parts of the gut-brain axis, play in developing various symptoms in cancer patients. The purpose of this systematic review was to describe the roles of inflammatory markers and the gut microbiome, as well as to describe their associations with psychoneurological symptoms and gastrointestinal toxicities in women with gynecologic cancers.

METHODS

A comprehensive literature search was conducted in PubMed, Embase, and Web of Science from January 2000 to February 2021. The Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines were utilized to screen the found articles. The quality of the included studies was assessed using the Mixed Method Assessment Tool. In the included studies, various inflammatory markers and gut microbiome diversity and patterns were measured.

RESULTS

Sixteen studies met the eligibility criteria and were included in this systematic review. While there were discrepancies in the associations between various inflammatory markers and symptoms, most of the studies showed positive correlations between interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α) and cancer-related psychoneurological symptoms and gastrointestinal toxicities in gynecologic cancer patients. Although there was no consensus in alpha diversity, studies showed significant dissimilarity in the microbial communities (beta diversity) in patients with gastrointestinal toxicities compared with patients without symptoms or healthy controls. Studies also reported inconsistent findings in the abundance of bacteria at different taxonomic levels. Radiation enteritis-derived microbiota could stimulate TNF-α and interleukin 1 beta (IL-1β) secretion.

CONCLUSIONS

Alteration of inflammatory markers, the gut microbiome, and their associations show emerging evidence in the development of psychoneurological symptoms and gastrointestinal toxicities in women with gynecologic cancers. More studies on the interactions between the immune system and the gut microbiome, two integral parts of the gut-brain axis, are required to shed light on the roles they play in symptom development.

How to Maintain a Healthy Gut Microbiome in Children with Cancer? Gut Microbiome Association with Diet in Children with Solid Tumors Postchemotherapy

Malnutrition is a common complication in children with cancer. Cancer treatment and malnutrition can disrupt gut microbiome diversity and composition. The gut microbiome is of broad interest to better understand the mechanisms of malnutrition in cancer therapy. This study aimed to compare the gut microbiome between children with solid tumors postchemotherapy and healthy controls, and investigated the association of the putative microbiome differences with diet. Study participants were 27 children (7-18 years) with solid tumors within the first year after the completion of chemotherapy and 22 healthy controls. The study groups did not have a statistically significant difference in age, race, sex, and body mass index. At study intake, the participants completed the Block Kids Food Screener for dietary intakes in the past week. Fecal specimens were collected and analyzed for the gut microbiome. The cancer and control groups differed in gut microbial β-diversity and abundance analyses. The macronutrient intakes such as carbohydrates, fiber, beta-carotene, and vitamin B6 were positively associated with α-diversity. Children with adequate vitamin B6 had a higher Chao1 diversity index than children with inadequate or excessive intake (p = 0.0004). Children with excessive selenium intake had a trend for higher Pielou's_e index than children with inadequate intake (p = 0.091). Maintaining a healthy gut microbiome is critical among children with cancer. This study provides new insights on the linkages between dietary intakes and the gut microbiome in children with solid tumors postchemotherapy. These findings, if replicated in future independent studies, may help anticipate malnutrition and plan for personalized nutrition approaches during chemotherapy in pediatric cancers.

Methodology Considerations in Studying Mental Health, Sleep Quality, and Biopsychosocial Determinants Among Chinese and Korean Americans During the COVID-19 Pandemic

Asians are one of the fastest-growing racial groups in the United States. The mental health of Asian Americans, particularly regarding depression and anxiety, needs significant attention. Various biopsychosocial factors interact to influence the risks of depression, anxiety, and sleep quality among Asian Americans. Currently, multiple methodological issues exist in the research of Asian Americans, such as limited data collection using Asian languages and inconsistent reporting of race and ethnicity data, which may be lacking entirely. All these methodological issues in research may account for the seemingly low prevalence rates of mental health problems among Asian Americans. In our study on mental health and sleep quality among Chinese and Korean Americans, we adopted multiple data collection strategies during the COVID-19 pandemic, including using culturally adaptive and validated measures as well as operating culture-sensitive procedures in the recruitment and data collection. The successful use of these strategies could promote early detection and personalized treatment of depression, anxiety, and sleep disturbance among Asian Americans. These strategies would further improve health care service use in this population.

International Registered Report Identifier IRRID

RR2-10.1136/bmjopen-2020-047281.

The Effect of Radiation and Chemoradiation Therapy on the Head and Neck Mucosal Microbiome: A Review

Radiation (RT) and chemoradiation therapy (CRT) play an essential role in head and neck cancer treatment. However, both cause numerous side effects in the oral cavity, paranasal sinuses, and pharynx, having deleterious consequences on patients’ quality of life. Concomitant with significant advances in radiation oncology, much attention has turned to understanding the role of the microbiome in the pathogenesis of treatment-induced tissue toxicity, to ultimately explore microbiome manipulation as a therapeutic intervention. This review sought to discuss current publications investigating the impact of RT and CRT-induced changes on the head and neck microbiome, using culture-independent molecular methods, and propose opportunities for future directions. Based on 13 studies derived from a MEDLINE, EMBASE, and Web of Science search on November 7, 2021, use of molecular methods has uncovered various phyla and genera in the head and neck microbiome, particularly the oral microbiome, not previously known using culture-based methods. However, limited research has investigated the impact of RT/CRT on subsites other than the oral cavity and none of the studies aimed to examine the relationship between the head and neck microbiome and treatment effectiveness. Findings from this review provide helpful insights on our current understanding of treatment-induced oral mucositis, dental plaque, and caries formation and highlight the need for future research to examine the effect of RT/CRT on the sinonasal and oropharyngeal microbiome. In addition, future research should use larger cohorts, examine the impact of the microbiome on treatment response, and study the effect of manipulating the microbiome to overcome therapy resistance.

Distinct Metagenomic Signatures in the SARS-CoV-2 Infection

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection can cause gastrointestinal symptoms in the patients, but the role of gut microbiota in SARS-CoV-2 infection remains unclear. Thus, in this study, we aim to investigate whether SARS-CoV-2 infection affects the composition and function of gut microbiota. In this study, we demonstrated for the first time that significant shifts in microbiome composition and function were appeared in both SARS-CoV-2-infected asymptomatic and symptomatic cases. The relative abundance of Candidatus_Saccharibacteria was significantly increased, whereas the levels of Fibrobacteres was remarkably reduced in SARS-CoV-2-infected cases. There was one bacterial species, Spirochaetes displayed the difference between patients and asymptomatic cases. On the genus level, Tyzzerella was the key species that remarkably increased in both symptomatic and asymptomatic cases. Analyses of genome annotations further revealed SARS-CoV-2 infection resulted in the significant 'functional dysbiosis' of gut microbiota, including metabolic pathway, regulatory pathway and biosynthesis of secondary metabolites etc. We also identified potential metagenomic markers to discriminate SARS-CoV-2-infected symptomatic and asymptomatic cases from healthy controls. These findings together suggest gut microbiota is of possible etiological and diagnostic importance for SARS-CoV-2 infection.

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.

Symptom Clusters in Head and Neck Cancer: A Systematic Review and Conceptual Model

OBJECTIVE

The two approaches to symptom-cluster research include grouping symptoms and grouping patients. The objective of this systematic review was to examine the conceptual approaches and methodologies used in symptom-cluster research in patients with head and neck cancer.

DATA SOURCES

Articles were retrieved from electronic databases (CINAHL, MEDLINE via Ovid, APA PsycINFO, Scopus, Embase, and Cochrane Central Register of Controlled Trials-CENTRAL), five grey literature portals, and Google Scholar. Seventeen studies met the eligibility criteria. Eight studies grouped symptoms to identify symptom clusters, of which two used qualitative methods. The number of symptom clusters ranged from two to five, and the number of symptoms in a cluster ranged from 2 to 11. Nine studies grouped patients based on their experiences with multiple symptoms. Cluster analysis and factor analysis were most commonly used. Despite variable names and composition of symptom clusters, synthesis revealed three prominent symptom clusters: general, head and neck cancer-specific, and gastrointestinal. Being female and quality of life were significantly associated with high symptom group or cluster severity. Biological mechanisms were sparsely examined.

CONCLUSION

Symptom cluster research in head and neck cancer is emerging. Consensus on nomenclature of a symptom cluster will facilitate deduction of core clinically relevant symptom clusters in head and neck cancer. Further research is required on understanding patients' subjective experiences, identifying predictors and outcomes, and underlying mechanisms for symptom clusters.

IMPLICATIONS FOR NURSING PRACTICE

Identification of clinically relevant symptom clusters would enable targeted symptom assessment and management strategies, thus improving treatment efficiencies and patient outcomes.

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).

Human Microbiome: Understanding the Role of the Gut Microbiome and Implications for Oncology Nursing Care

By understanding the human microbiome and its influencing factors, oncology nurses in clinical practice can educate, screen, and monitor patients with cancer who have a higher risk of gut microbiome dysbiosis. Knowledge of the gut microbiome and its impact on cancer outcomes can help oncology nurses interpret associations between the gut microbiome and treatment- related toxicities and symptoms. Oncology nurses can guide patients to build a healthy gut microbiome across the trajectory of cancer treatment and survivorship.

Acute Radiation Syndrome and the Microbiome: Impact and Review

Study of the human microbiota has been a centuries-long endeavor, but since the inception of the National Institutes of Health (NIH) Human Microbiome Project in 2007, research has greatly expanded, including the space involving radiation injury. As acute radiation syndrome (ARS) is multisystemic, the microbiome niches across all areas of the body may be affected. This review highlights advances in radiation research examining the effect of irradiation on the microbiome and its potential use as a target for medical countermeasures or biodosimetry approaches, or as a medical countermeasure itself. The authors also address animal model considerations for designing studies, and the potential to use the microbiome as a biomarker to assess radiation exposure and predict outcome. Recent research has shown that the microbiome holds enormous potential for mitigation of radiation injury, in the context of both radiotherapy and radiological/nuclear public health emergencies. Gaps still exist, but the field is moving forward with much promise.

Exploring the Potential Role of the Gut Microbiome in Chemotherapy-Induced Neurocognitive Disorders and Cardiovascular Toxicity

Chemotherapy, targeting not only malignant but also healthy cells, causes many undesirable side effects in cancer patients. Due to this fact, long-term cancer survivors often suffer from late effects, including cognitive impairment and cardiovascular toxicity. Chemotherapy damages the intestinal mucosa and heavily disrupts the gut ecosystem, leading to gastrointestinal toxicity. Animal models and clinical studies have revealed the associations between intestinal dysbiosis and depression, anxiety, pain, impaired cognitive functions, and cardiovascular diseases. Recently, a possible link between chemotherapy-induced gut microbiota disruption and late effects in cancer survivors has been proposed. In this review, we summarize the current understanding of preclinical and clinical findings regarding the emerging role of the microbiome and the microbiota-gut-brain axis in chemotherapy-related late effects affecting the central nervous system (CNS) and heart functions. Importantly, we provide an overview of clinical trials evaluating the relationship between the gut microbiome and cancer survivorship. Moreover, the beneficial effects of probiotics in experimental models and non-cancer patients with neurocognitive disorders and cardiovascular diseases as well as several studies on microbiota modulations via probiotics or fecal microbiota transplantation in cancer patients are discussed.