Alterations in Patterns of Gene Expression and Perturbed Pathways in the Gut-Brain Axis Are Associated With Chemotherapy-Induced Nausea

Influence of Gut Microbiota-Mediated Immune Regulation on Response to Chemotherapy

The involvement of the gut microbiota in anti-cancer treatment has gained increasing attention. Alterations to the structure and function of the gut bacteria are important factors in the development of cancer as well as the efficacy of chemotherapy. Recent studies have confirmed that the gut microbiota and related metabolites influence the pharmacological activity of chemotherapeutic agents through interactions with the immune system. This review aims to summarize the current knowledge of how malignant tumor and chemotherapy affect the gut microbiota, how the gut microbiota regulates host immune response, and how interactions between the gut microbiota and host immune response influence the efficacy of chemotherapy. Recent advances in strategies for increasing the efficiency of chemotherapy based on the gut microbiota are also described. Deciphering the complex homeostasis maintained by the gut microbiota and host immunity provides a solid scientific basis for bacterial intervention in chemotherapy.

Sentinel and networked symptoms in patients with breast cancer undergoing chemotherapy

PURPOSE

It was designed to identify the symptom clusters and sentinel symptoms among patients with breast cancer receiving chemotherapy at the community level, and to explore core and bridge symptoms at the global level.

METHODS

A cross-sectional survey was conducted using the MD Anderson Symptom Inventory. Patients with breast cancer receiving chemotherapy, recruited from the "Be Resilient to Breast Cancer" project between January 2023 and December 2023, were included in the study. Symptom clusters and their sentinel symptoms were identified using exploratory factor analysis and Apriori algorithm. Core and bridge symptoms were identified using network analysis.

RESULTS

A total of 468 patients with breast cancer participated in the current study. At the community level, three symptom clusters and their corresponding sentinel symptoms were identified: a gastrointestinal symptom cluster (with nausea as the sentinel symptom), a psycho-sleep-related symptom cluster (with distress as the sentinel symptom), and a neurocognition symptom cluster (with dry mouth as the sentinel symptom). At the global level, fatigue emerged as the core symptom, while disturbed sleep and lack of appetite as bridge symptoms.

CONCLUSION

Addressing nausea, distress, and dry mouth are imperative for alleviating specific symptom clusters at the community level. Furthermore, targeting fatigue, disturbed sleep, and lack of appetite are crucial to break the interactions among diverse symptoms at the global level.

Associations of differentially expressed genes with psychoneurological symptoms in patients with head and neck cancer: A longitudinal study

OBJECTIVE

Patients with head and neck cancer (HNC) experience psychoneurological symptoms (PNS, i.e., depression, fatigue, sleep disturbance, pain, and cognitive dysfunction) during intensity-modulated radiotherapy (IMRT) that negatively impact their functional status, quality of life, and overall survival. The underlying mechanisms for PNS are still not fully understood. This study aimed to examine differentially expressed genes and pathways related to PNS for patients undergoing IMRT (i.e., before, end of, 6 months, and 12 months after IMRT).

METHODS

Participants included 142 patients with HNC (mean age 58.9 ± 10.3 years, 72.5% male, 83.1% White). Total RNA extracted from blood leukocytes were used for genome-wide gene expression assays. Linear mixed effects model was used to examine the association between PNS and gene expression across time. Gene Ontology (GO) enrichment analysis was employed to identify pathways related to PNS.

RESULTS

A total of 1352 genes (162 upregulated, 1190 downregulated) were significantly associated with PNS across time (false discovery rate (FDR) < 0.05). Among these genes, 112 GO terms were identified (FDR < 0.05). The top 20 GO terms among the significant upregulated genes were related to immune and inflammatory responses, while the top 20 GO terms among the significant downregulated genes were associated with telomere maintenance.

CONCLUSION

This study is the first to identify genes and pathways linked to immune and inflammatory responses and telomere maintenance that are associated with PNS in patients with HNC receiving IMRT. Inflammation and aging markers may be candidate biomarkers for PNS. Understanding biological markers may produce targets for novel interventions.

Distinct Nausea Profiles Are Associated With Gastrointestinal Symptoms in Oncology Patients Receiving Chemotherapy

BACKGROUND

Unrelieved chemotherapy-induced nausea (CIN) occurs 48% of patients undergoing chemotherapy and is one of the most debilitating symptoms that patients report.

OBJECTIVE

The aims of this study were to identify subgroups of patients with distinct CIN profiles and determine how these subgroups differed on demographic and clinical characteristics; severity, frequency, and distress of CIN; and the co-occurrence of common gastrointestinal symptoms.

METHODS

Patients (n = 1343) completed demographic questionnaire and Memorial Symptom Assessment Scale 6 times over 2 cycles of chemotherapy. Latent class analysis was used to identify subgroups of patients with distinct CIN profiles. Differences among these subgroups were evaluated using parametric and nonparametric statistics.

RESULTS

Four distinct CIN profiles were identified: none (40.8%), increasing-decreasing (21.5%), decreasing (8.9%), and high (28.8%). Compared with the none class, patients in the high class were younger, had a lower annual household income, had child care responsibilities, had a lower Karnofsky Performance Status score and a higher Self-administered Comorbidity Questionnaire score, and were more likely to have received chemotherapy on a 14-day cycle and a highly emetogenic chemotherapy regimen. In addition, patients in the high class reported high occurrence rates for dry mouth, feeling bloated, diarrhea, lack of appetite, abdominal cramps, difficulty swallowing, mouth sores, weight loss, and change in the way food tastes.

CONCLUSIONS

That 60% of the patients reported moderate to high CIN occurrence rates confirms that this unrelieved symptom is a significant clinical problem.

IMPLICATIONS FOR PRACTICE

Nurses need to evaluate patients' level of adherence to their antiemetic regimen and make appropriate referrals for physical therapy, psychological services, and dietary counseling.

Perturbations in Neuroinflammatory Pathways Are Associated With a Worst Pain Profile in Oncology Patients Receiving Chemotherapy

Unrelieved pain occurs in 55% of cancer patients. Identification of molecular mechanisms for pain may provide insights into therapeutic targets. Purpose was to evaluate for perturbations in neuroinflammatory pathways between oncology patients with and without severe pain. Worst pain severity was rated using a 0 to 10 numeric rating scale six times over two cycles of chemotherapy. Latent profile analysis was used to identify subgroups of patients with distinct pain profiles. Pathway impact analyses were performed in two independent samples using gene expression data obtained from RNA sequencing (n = 192) and microarray (n = 197) technologies. Fisher's combined probability test was used to identify significantly perturbed pathways between None versus the Severe pain classes. In the RNA sequencing and microarray samples, 62.5% and 56.3% of patients were in the Severe pain class, respectively. Nine perturbed pathways were related to neuroinflammatory mechanisms (i.e., retrograde endocannabinoid signaling, gamma-aminobutyric acid synapse, glutamatergic synapse, Janus kinase-signal transducer and activator of transcription signaling, phagosome, complement and coagulation cascades, cytokine-cytokine receptor interaction, chemokine signaling, calcium signaling). First study to identify perturbations in neuroinflammatory pathways associated with severe pain in oncology outpatients. Findings suggest that complex neuroimmune interactions are involved in the maintenance of chronic pain conditions. Perspective: In this study that compared oncology patients with none versus severe pain, nine perturbed neuroinflammatory pathways were identified. Findings suggest that complex neuroimmune interactions are involved in the maintenance of persistent pain conditions.

Gastrointestinal Symptom Cluster is Associated With Epigenetic Regulation of Lymphotoxin Beta in Oncology Patients Receiving Chemotherapy

OBJECTIVES

While the gastrointestinal symptom cluster (GISC) is common in patients receiving chemotherapy, limited information is available on its underlying mechanism(s). Emerging evidence suggests a role for inflammatory processes through the actions of the nuclear factor kappa B (NF-κB) signaling pathway. This study evaluated for associations between a GISC and levels of DNA methylation for genes within this pathway.

METHODS

Prior to their second or third cycle of chemotherapy, 1071 outpatients reported symptom occurrence using the Memorial Symptom Assessment Scale. A GISC was identified using exploratory factor analysis. Differential methylation analyses were performed in two independent samples using EPIC (n = 925) and 450K (n = 146) microarrays. Trans expression-associated CpG (eCpG) loci for 56 NF-κB signaling pathway genes were evaluated. Loci significance were assessed using an exploratory false discovery rate (FDR) of 25% for the EPIC sample. For the validation assessment using the 450K sample, significance was assessed at an unadjusted p-value of 0.05.

RESULTS

For the EPIC sample, the GISC was associated with increased expression of lymphotoxin beta (LTB) at one differentially methylated trans eCpG locus (cg03171795; FDR = 0.168). This association was not validated in the 450K sample.

CONCLUSIONS

This study is the first to identify an association between a GISC and epigenetic regulation of a gene that is involved in the initiation of gastrointestinal immune responses. Findings suggest that increased LTB expression by hypermethylation of a trans eCpG locus is involved in the occurrence of this cluster in patients receiving chemotherapy. LTB may be a potential therapeutic target for this common cluster.

Perturbations in common and distinct inflammatory pathways associated with morning and evening fatigue in outpatients receiving chemotherapy

BACKGROUND

Moderate to severe fatigue occurs in up to 94% of patients with cancer. Recent evidence suggests that morning and evening fatigue are distinct dimensions of physical fatigue. The purposes of this study were to evaluate the transcriptome for common and distinct perturbed inflammatory pathways in patients receiving chemotherapy who reported low versus high levels of morning or low versus high levels of evening cancer-related fatigue.

METHODS

Patients completed questionnaires during the week prior to their chemotherapy treatment. Severity of morning and evening fatigue was evaluated using the Lee Fatigue Scale. Gene expression and pathway impact analyses (PIA) were performed in two independent samples using RNA-sequencing (n = 357) and microarray (n = 360). Patterns of interactions between and among these perturbed pathways were evaluated using a knowledge network (KN).

RESULTS

Across the PIA, nine perturbed pathways (FDR < 0.025) were common to both morning and evening fatigue, six were distinct for morning fatigue, and four were distinct for evening fatigue. KN (19 nodes, 39 edges) identified the phosphatidylinositol 3-kinase (PI3K)-Akt pathway node (perturbed in evening fatigue) with the highest betweenness (0.255) and closeness (0.255) centrality indices. The next highest betweenness centrality indices were seen in pathways perturbed in evening fatigue (i.e., nuclear factor kappa B: 0.200, natural killer cell-mediated cytotoxicity: 0.178, mitogen-activated protein kinase: 0.175).

CONCLUSIONS

This study describes perturbations in common and distinct inflammatory pathways associated with morning and/or evening fatigue. PI3K-Akt was identified as a bottleneck pathway. The analysis identified potential targets for therapeutic interventions for this common and devastating clinical problem.

Metagenomics and chemotherapy-induced nausea: A roadmap for future research

Uncontrolled chemotherapy-induced nausea and vomiting can reduce patients' quality of life and may result in premature discontinuation of chemotherapy. Although nausea and vomiting are commonly grouped together, research has shown that antiemetics are clinically effective against chemotherapy-induced vomiting (CIV) but less so against chemotherapy-induced nausea (CIN). Nausea remains a problem for up to 68% of patients who are prescribed guideline-consistent antiemetics. Despite the high prevalence of CIN, relatively little is known regarding its etiology independent of CIV. This review summarizes a metagenomics approach to the study and treatment of CIN with the goal of encouraging future research. Metagenomics focuses on genetic risk factors and encompasses both human (ie, host) and gut microbial genetic variation. Little work to date has focused on metagenomics as a putative biological mechanism of CIN. Metagenomics has the potential to be a powerful tool in advancing scientific understanding of CIN by identifying new biological pathways and intervention targets. The investigation of metagenomics in the context of well-established demographic, clinical, and patient-reported risk factors may help to identify patients at risk and facilitate the prevention and management of CIN.

Multiple Gastrointestinal Symptoms Are Associated With Chemotherapy-Induced Nausea in Patients With Breast Cancer

BACKGROUND

Unrelieved chemotherapy-induced nausea (CIN) is a significant problem for patients with breast cancer (BC).

OBJECTIVE

In a sample of patients with BC who were assessed before their second or third cycle of chemotherapy, study purposes were to evaluate for the occurrence, severity, frequency, and distress associated with CIN; evaluate for differences in demographic and clinical characteristics and gastrointestinal (GI) symptom occurrence rates between patients who did and did not report CIN; and determine which demographic, clinical, and symptom characteristics were associated with the occurrence of CIN.

METHODS

Patients completed demographic and clinical questionnaires and the Memorial Symptom Assessment Scale for nausea and common GI symptom assessments. Univariate analyses evaluated for differences in demographic and clinical characteristics and GI symptom occurrence between patients who did and did not report CIN. Multiple logistic regression analysis evaluated for characteristics associated with CIN.

RESULTS

Of the 532 patients with BC, 47.2% reported CIN occurrence. Characteristics associated with CIN group membership were poorer functional status, receipt of chemotherapy on a 14-day cycle, and higher occurrence rates of 5 GI symptoms (ie, dry mouth, vomiting, constipation, change in the way food tastes, and lack of appetite; all P < .001).

CONCLUSIONS

Unrelieved CIN is a common symptom in patients with BC. This study is the first to demonstrate that 5 co-occurring GI symptoms were associated with CIN occurrence.

IMPLICATIONS FOR PRACTICE

This study identified new risk factors for CIN occurrence in patients with BC. Clinicians may be able to initiate additional interventions to alleviate CIN.

Cancer-related cognitive impairment is associated with perturbations in inflammatory pathways

Cancer-related cognitive impairment (CRCI) is a significant problem for patients receiving chemotherapy. While a growing amount of pre-clinical and clinical evidence suggests that inflammatory mechanisms underlie CRCI, no clinical studies have evaluated for associations between CRCI and changes in gene expression. Therefore, the purpose of this study was to evaluate for differentially expressed genes and perturbed inflammatory pathways across two independent samples of patients with cancer who did and did not report CRCI. The Attentional Function Index (AFI) was the self-report measure used to assess CRCI. AFI scores of <5 and of >7.5 indicate low versus high levels of cognitive function, respectively. Of the 185 patients in Sample 1, 49.2% had an AFI score of <5 and 50.8% had an AFI score of >7.5. Of the 158 patients in Sample 2, 50.6% had an AFI score of <5 and 49.4% had an AFI score of >7.5. Data from 182 patients in Sample 1 were analyzed using RNA-seq. Data from 158 patients in Sample 2 were analyzed using microarray. Twelve KEGG signaling pathways were significantly perturbed between the AFI groups, five of which were signaling pathways related to inflammatory mechanisms (e.g., cytokine-cytokine receptor interaction, tumor necrosis factor signaling). This study is the first to describe perturbations in inflammatory pathways associated with CRCI. Findings highlight the role of cytokines both in terms of cytokine-specific pathways, as well as pathways involved in cytokine production and cytokine activation. These findings have the potential to identify new targets for therapeutics and lead to the development of interventions to improve cognition in patients with cancer.

Precision Health and Nursing: Seeing the Familiar in the Foreign

Precision health is the integration of personal genomic data with biological, environmental, behavioral, and other information relevant to the care of a patient. Genetics and genomics are essential components of precision health. Genetics is the study of the effects of individual genes, and genomics is the study of all the components of the genome and interactions between genes, environmental factors, and other psychosocial and cultural factors. Knowledge about the role of genetics and genomics on health outcomes has increased substantially since the completion of the human genome project in 2003. Insights about genetics and genomics obtained from bench science are now having positive clinical implications on patient health outcomes. Nurses have the potential to make distinct contributions to precision health due to their unique role in the health care system. In this article, we discuss gaps in the development of precision health in nursing and how nursing can expand the definition of precision health to actualize its potential. Precision health plays a role in nursing practice. Understanding this connection positions nurses to incorporate genetic and genomic knowledge into their nursing practice.

Neuropsychological Symptoms and Intrusive Thoughts Are Associated With Worse Trajectories of Chemotherapy-Induced Nausea

CONTEXT

Although chemotherapy-induced vomiting is well controlled with evidence-based antiemetic regimens, chemotherapy-induced nausea (CIN) remains a significant clinical problem.

OBJECTIVES

Study purposes, in a sample of outpatients with breast, gastrointestinal, gynecological, or lung cancer who received two cycles of chemotherapy (CTX, n = 1251), were to evaluate for interindividual differences in the severity of CIN and to determine which demographic, clinical, symptom, and stress characteristics are associated with higher initial levels as well as with the trajectories of CIN.

METHODS

Patients were recruited during their first or second cycle of CTX. Patients completed self-report questionnaires a total of six times over two cycles of CTX. Hierarchical linear modeling was used to evaluate for interindividual differences in and characteristics associated with the severity of CIN.

RESULTS

Across the two cycles of CTX, higher levels of sleep disturbance, depression, and morning fatigue, as well as higher levels of intrusive thoughts, were associated with higher initial levels of CIN. In addition, lower functional status scores and shorter cycle lengths were associated with higher initial levels of CIN, and younger age and higher emetogenicity of the CTX regimen were associated with both higher initial levels as well as worse trajectories of CIN severity.

CONCLUSION

These findings suggest that common symptoms associated with cancer and its treatment are associated with increased severity of CIN. Targeted interventions for these symptoms may reduce the burden of unrelieved CIN.

Gastrointestinal symptoms are associated with trajectories of chemotherapy-induced nausea

PURPOSE

Between 19 and 58% of oncology patients experience chemotherapy-induced nausea (CIN). In a sample of outpatients with breast, gastrointestinal (GI), gynecological, and lung cancer, the study purposes were to evaluate for inter-individual differences in the severity of CIN over two cycles of chemotherapy (CTX) and to determine which demographic and clinical characteristics and GI symptoms were associated with higher initial levels as well as with the trajectories of CIN severity.

METHODS

Patients completed study questionnaires at six time points over two cycles of CTX. These questionnaires provided information on demographic and clinical characteristics, as well as the occurrence of twelve GI symptoms. Hierarchical linear modeling based on full maximum likelihood estimation was performed.

RESULTS

Of the 1251 patients, 47.2% reported CIN. Across two cycles of CTX, lower functional status scores and higher levels of comorbidity were associated with higher initial levels of CIN. Younger age and emetogenicity of the CTX regimen were associated with higher initial levels as well as worse trajectories of CIN. The occurrence of five GI symptoms (i.e., vomiting, lack of appetite, constipation, feeling bloated, and difficulty swallowing) was associated with higher initial levels of CIN. The occurrence of mouth sores was associated with higher initial levels as well as with worst trajectories of CIN.

CONCLUSIONS

This study is the first to identify distinct demographic, clinical, and GI symptom characteristics associated with CIN severity. These findings suggest that the etiology of CIN is complex and may warrant interventions beyond standard antiemetics.