Possible Bioenergetic Biomarker for Chronic Cancer-Related Fatigue.

BACKGROUND: Cancer-related fatigue (CRF) is a highly prevalent, debilitating, and persistent symptom experienced by patients receiving cancer treatments. Up to 71% of men with prostate cancer receiving radiation therapy experience acute and persistent CRF. There is neither an effective therapy nor a diagnostic biomarker for CRF. This pilot study aimed to discover potential biomarkers associated with chronic CRF in men with prostate cancer receiving radiation therapy. METHODS: We used a longitudinal repeated-measures research design. Twenty men with prostate cancer undergoing radiation therapy completed all study visits. CRF was evaluated by a well-established and validated questionnaire, the Patient-Reported Outcomes Measurement Information System for Fatigue (PROMIS-F) Short Form. In addition, peripheral blood mononuclear cells were harvested to quantify ribonucleic acid (RNA) gene expression of mitochondria-related genes. Data were collected before, during, on completion, and 24 months postradiation therapy and analyzed using paired t-tests and repeated-measures analysis of variance. RESULTS: The mean of the PROMIS-F T score was significantly increased over time in patients with prostate cancer, remaining elevated at 24 months postradiation therapy compared to baseline. A significant downregulated BC1 ubiquinol-cytochrome c reductase synthesis-like (BCS1L) was observed over time during radiation therapy and at 24 months postradiation therapy. An increased PROMIS-F score was trended with downregulated BCS1L in patients 24 months after completing radiation therapy. DISCUSSION: This is the first evidence to describe altered messenger RNA for BCS1L in chronic CRF using the PROMIS-F measure with men receiving radiation therapy for prostate cancer. CONCLUSION: Our results suggest that peripheral blood mononuclear cell messenger RNA for BCS1L is a potential biomarker and therapeutic target for radiation therapy-induced chronic CRF in this clinical population.

Consortium Building for Nurse Scientists Interested in Symptoms Research in the Era of Precision Health.

PURPOSE: This article aims to provide perspectives on the establishment of a consortium for nurse scientists with similar career trajectories interested in cancer-related symptoms (CRS) research. Hereby, we describe the development of and recent outcomes from the CRS consortium, the lessons learned in establishing the consortium, and future directions to advance the science of CRS. MODEL AND METHODS: New and innovative strategies are needed to address the complexity of CRS research. A CRS consortium was created to allow a mechanism for oncology nurse scientists with varying expertise to collaborate to advance CRS research. The National Institutes of Health (NIH) Symptom Science Model (SSM) guides the research of the CRS Consortium. DISCUSSION AND CONCLUSIONS: A need for improved CRS assessment and management has been identified. The CRS consortium was created as a collaborative think tank to begin to address this need. Guided by the NIH SSM, CRS consortium members have worked to define symptom phenotypes, enhance understanding of the biologic mechanisms that can contribute to symptom phenotypes, and develop tailored interventions to improve symptom management. Dissemination of the CRS consortium efforts involve publications and presentations. CLINICAL IMPLICATIONS: Nurse scientists interested in symptom science and biobehavorial research face many challenges on how to initiate and sustain independent programs of research. Through the formation of a CRS consortium, oncology nurse scientists can work together to address identified issues in symptom measurement and management.

Analyzing mitochondrial function in human peripheral blood mononuclear cells.

Mitochondrial oxidative phosphorylation (OXPHOS) is responsible for producing most of the adenosine triphosphate required by eukaryotic cells. Lymphocytes make up the majority of the peripheral blood mononuclear cells. Peripheral blood mononuclear cells are readily obtainable, providing an ideal sample to monitor systemic changes and understand molecular signaling mechanisms in disease processes. Mitochondrial energy metabolism of lymphocyte has been used to screen for OXPHOS disorders. While there are increasing studies of lymphocyte OXPHOS, few studies examined activity of electron transport chain of lymphocyte mitochondria. We present an optimal protocol to harvest fresh peripheral blood mononuclear cells from human whole blood, determine integrated mitochondrial function, and analyze electron transport chain complex activity. Analyzing integrated mitochondrial function using OXPHOS provides data to uncover defects in the transport of substrates into the mitochondria, generation of reducing equivalents, the electron transport chain, and coupling to the production of adenosine triphosphate. The optimal conditions to harvest peripheral blood mononuclear cells were using blood anticoagulated with ethylenediaminetetraacetic acid, processed utilizing Lymphoprep™, and washed in phosphate buffered saline, all at room temperature. Using isolated peripheral blood mononuclear cells, integrated mitochondrial function and the activities of electron transport chain were determined.

Symptom self-management strategies in patients with non-metastatic prostate cancer.

AIMS AND OBJECTIVES: To explore the association between symptoms, symptom distress and symptom self-management and to identify effective strategies of symptom self-management in men with non-metastatic prostate cancer following radical prostatectomy or radiation therapy. BACKGROUND: Men receiving treatments for localised prostate cancer experience symptoms of urinary incontinence, urinary obstruction/irritation, bowel difficulties and sexual dysfunction. Understanding patients' symptom experiences and identifying strategies that they use to manage these symptoms are imperative for symptom management planning. DESIGN: A descriptive, cross-sectional study was conducted with a sample of 53 men, who were within three months of the initiation of their treatment. METHODS: The Symptom Indexes and the Strategy and Effectiveness of Symptom Self-Management questionnaires were used to measure symptoms, symptom distress and symptom self-management. Descriptive statistics, t-tests, correlations and multiple regressions were used to analyse the data. RESULTS: Symptoms were significantly correlated with symptom-related distress (r = 0·67, p < 0·01). Frequency of symptoms was significantly associated with symptom self-management strategies for urinary (ß = 0·50, p < 0·01), bowel (ß = 0·71, p < 0·01) and sexual problems (ß = 0·28, p = 0·05). The most effective strategies were as follows: pads and doing Kegel exercise for managing urinary problems, rest and endurance for bowel symptoms, and expressing feelings and finding alternative ways to express affection for management of sexual dysfunction. CONCLUSIONS: Assessing symptom self-management among men with newly diagnosed prostate cancer can help healthcare providers develop strategies that will enhance health-related quality of life. RELEVANCE TO CLINICAL PRACTICE: Results provide information on effective strategies that patients with prostate cancer found to reduce their symptoms. The strategies used provide a foundation for developing and testing interventions for personalised symptom management.

Relationship of cancer-related fatigue with psychoneurophysiological (PNP) symptoms in breast cancer survivors.

PURPOSE: Cancer-related fatigue (CRF) is a highly prevalent and debilitating symptom reported by breast cancer survivors (BCS). CRF has been associated with the co-occurrence of anxiety, depression, poor sleep quality, cognitive impairment, which are collectively termed as psychoneurophysiological (PNP) symptoms. CRF and these PNP symptoms are often reported during and after treatment with long-lasting distress. It is unclear how CRF and these PNP symptoms influence each other. This study aimed to explore predictive factors (i.e., PNP symptoms and social-demographic factors) of CRF, and test exploratory path models of the relationships of CRF with PNP symptoms (depression, anxiety, sleep disturbance, pain, and cognitive function) in BCS. METHODS: This paper is part of a larger descriptive, correlational, and cross-sectional study. Validated and reliable instruments assessed CRF, depression, anxiety, sleep disturbance, pain, and cognitive function. Descriptive statistics, Pearson correlation, multiple linear regression models, and path analysis were employed. RESULTS: Patients (N = 373) who reported less bodily pain had worst CRF (r = -0.45, p < .01). Significant predictors of CRF included depression, sleep disorder, bodily pain, perceived cognitive ability, and dispositional (state) optimism. Depression alone accounted for 31% of the variance in CRF. An integrative path model with bodily pain, neuropathic pain, CRF, and depression showed a good fit across different indices (CFI = 0.993, RMSEA = 0.047, 90% CI 0-0.12, SRMR = 0.027). CONCLUSIONS: This study identified significant predictors of CRF and revealed a good fit mediation model with significant pathways for CRF, suggesting that a common etiology may underpin the co-occurrence of CRF with PNP symptoms (pain and depression). However, further investigation with longitudinal design is necessary to explore the causal relationships of these symptoms. Evidence-based strategies/interventions are needed to reduce or eliminate the burden of these symptoms on the lives of BCS.

The association of IFI27 expression and fatigue intensification during localized radiation therapy: implication of a para-inflammatory bystander response.

The mechanisms behind fatigue intensification during cancer therapy remain elusive. The interferon alpha-inducible protein 27 (IFI27) was the most up-regulated gene based on our previous microarray data in fatigued men with non-metastatic prostate cancer receiving localized external beam radiation therapy (EBRT). The purpose of this study was to confirm the IFI27 up-regulation and determine its association with fatigue intensification during EBRT. Peripheral blood samples and fatigue scores were collected at three time points--prior to EBRT, at midpoint, and at completion of EBRT. Confirmatory quantitative real time polymerase chain reaction (qPCR) and enzyme-linked immunosorbent assay (ELISA) were utilized to verify the microarray results. Subjects were a total of 40 Caucasian men with prostate cancer; 20 scheduled for EBRT (65.6 ± 7.5 years old), and 20 on active surveillance as controls (62.8 ± 6.1 years old). Significant IFI27 expression overtime during EBRT was confirmed by qPCR (p < 0.5), which correlated with fatigue scores during EBRT (R = -0.90, p = 0.006). Alterations in mechanisms associated with immune response and mitochondrial function that explain the up-regulation of IFI27 may provide an understanding of the pathways related to the intensification of fatigue during localized radiation therapy.

Family Wellbeing and Sexual Health of Patients Receiving Treatment for Prostate Cancer.

Purpose: Prostate cancer and its treatment may affect patients' sexual function and social wellbeing. This study investigated the relationship between social/family wellbeing and sexual health in patients with prostate cancer. Additionally, the moderating effect of clinical characteristics on this relationship was also explored. Patients and Methods: This is a descriptive correlational study using baseline data of a longitudinal study enrolling 137 patients with prostate cancer. Sexual Function (SF) and Sexual Function Distress (SFD) data were collected using the Symptom Index questionnaire. Demographic data were obtained during study intake and clinical data were obtained from chart review. Bivariate correlation determined the correlations among continuous demographic/clinical data, social/family wellbeing, and sexual health. Moderated regression analysis determined the moderating effects of clinical characteristics on the relationship of social/family wellbeing and sexual health. Results: Moderate positive correlation was found between social/family wellbeing and SF, whereas a weak negative correlation was noted between social/family wellbeing and SFD. Depression was significantly correlated with social/family wellbeing and SFD. Both sexual health domains were significantly correlated with Gleason score. A significant difference was noted in the social/family wellbeing and both SF and SFD in participants receiving androgen deprivation therapy (ADT) compared to those not receiving ADT. Concomitant ADT use was the only clinical characteristic found to be a significant moderator of the relationship between social/family wellbeing and SFD, but none of the clinical characteristics was found to have a moderating effect on the relationship of social/family wellbeing and SF. Among patients who were not receiving ADT, high social/family wellbeing was associated with low SFD. Patients who were receiving ADT reported slightly higher SFD despite having higher social/family wellbeing. Conclusion: Ensuring sexual health in patients with prostate cancer requires a comprehensive approach to address factors contributing to sexual health such as side effects of treatment and family wellbeing.

Brain-Derived Neurotrophic Factor rs6265 polymorphism is associated with severe cancer-related fatigue and neuropathic pain in female cancer survivors.

PURPOSE: This study examined the relationships between a single-nucleotide polymorphism (SNP) of brain-derived neurotrophic factor (BDNF) rs6265 and psychoneurological (PN) symptoms in female cancer survivors. METHODS: This secondary analysis examined 393 study participants. In addition to demographic variables, self-reported PN symptom scores (anxiety, bodily pain, depression, fatigue, neuropathic pain, and sleep disturbance) were collected using the Patient-Reported Outcomes Measurement Information System and 36-Item Short-Form Health Survey. Buccal swab samples were collected to obtain genotypes for BDNF rs6265 (Val/Val, Val/Met, or Met/Met). The PN symptom scores were compared across genotypes, and the relationships were examined using a regression model. We also explored correlations between different symptoms within each genotype. RESULTS: Participants with the Met/Met genotype reported significantly worse cancer-related fatigue and neuropathic pain, which was confirmed by rank-based regression analysis. In addition, cancer-related fatigue was correlated with other PN symptoms, particularly depression. These correlations were stronger in study participants with the Met/Met genotype than those with other genotypes. CONCLUSION: Our study suggests that female cancer survivors with the Met/Met genotype of BDNF rs6265 are likely to experience worse cancer-related fatigue and neuropathic pain and that cancer-related fatigue is a good predictor of co-occurring PN symptoms in this population. IMPLICATIONS FOR CANCER SURVIVORS: Our findings advance the scientific community's understanding of cancer-related PN symptoms experienced by female cancer survivors, especially the unique role of BDNF rs6265 polymorphism in these symptoms. Our findings offer valuable insights for clinical practice that the symptom experience among female cancer survivors may vary based on BDNF genotypes.

The High-Intensity Exercise Study to Attenuate Limitations and Train Habits in Older Adults With HIV (HEALTH): A Research Protocol.

ABSTRACT: The High-Intensity Exercise Study to Attenuate Limitations and Train Habits in Older Adults With HIV (HEALTH), which incorporates an exercise and biobehavioral coaching intervention, has the following overall goals: (a) to determine whether high-intensity interval training (HIIT) mitigates physical function impairments, fatigue, and impairments in mitochondrial bioenergetics of older people living with HIV (PLWH) to a greater extent than continuous moderate exercise (CME); and (b) to determine whether a biobehavioral coaching and mobile health text messaging intervention after HIIT or CME can promote long-term adherence to physical activity. The HEALTH study is a randomized trial of 100 older PLWH (≥50 years of age) who self-report fatigue and have a sedentary lifestyle. Enrolled participants will be randomized to 16 weeks of supervised HIIT or CME training, followed by a 12-week maintenance phase, involving a mobile health coaching intervention. Outcomes of the HEALTH study will inform the development of scalable, effective exercise recommendations tailored to the unique needs of aging PLWH.

Blocked O-GlcNAc cycling alters mitochondrial morphology, function, and mass.

O-GlcNAcylation is a prevalent form of glycosylation that regulates proteins within the cytosol, nucleus, and mitochondria. The O-GlcNAc modification can affect protein cellular localization, function, and signaling interactions. The specific impact of O-GlcNAcylation on mitochondrial morphology and function has been elusive. In this manuscript, the role of O-GlcNAcylation on mitochondrial fission, oxidative phosphorylation (Oxphos), and the activity of electron transport chain (ETC) complexes were evaluated. In a cellular environment with hyper O-GlcNAcylation due to the deletion of O-GlcNAcase (OGA), mitochondria showed a dramatic reduction in size and a corresponding increase in number and total mitochondrial mass. Because of the increased mitochondrial content, OGA knockout cells exhibited comparable coupled mitochondrial Oxphos and ATP levels when compared to WT cells. However, we observed reduced protein levels for complex I and II when comparing normalized mitochondrial content and reduced linked activity for complexes I and III when examining individual ETC complex activities. In assessing mitochondrial fission, we observed increased amounts of O-GlcNAcylated dynamin-related protein 1 (Drp1) in cells genetically null for OGA and in glioblastoma cells. Individual regions of Drp1 were evaluated for O-GlcNAc modifications, and we found that this post-translational modification (PTM) was not limited to the previously characterized residues in the variable domain (VD). Additional modification sites are predicted in the GTPase domain, which may influence enzyme activity. Collectively, these results highlight the impact of O-GlcNAcylation on mitochondrial dynamics and ETC function and mimic the changes that may occur during glucose toxicity from hyperglycemia.

Genetic Correlates of Fatigue in Individuals with End Stage Renal Disease.

Fatigue is a prevalent symptom associated with decreased quality of life and increased mortality in individuals with end stage renal disease (ESRD), yet causes of fatigue in individuals with ESRD remain poorly understood. We examined gene expression of Neuronal PAS Domain Protein 2 (NPAS2) in relation to patient-reported fatigue in 122 individuals with ESRD. Independent samples t-tests were used to examine NPAS2 gene expression profiles of: non-fatigue versus fatigue. Multivariable regression analyses were used to examine the relationship between fatigue and numerous variables including depression. Participants were approximately 58 years old (+/- 13.2 years), 78% African American (n = 95), and 72% male (n = 88). The phenotype of fatigue was not significantly associated with gene expression of NPAS2 but was significantly associated with depression (p< .001). This study suggests that further research should examine the causal mechanism between depression and fatigue in order to identify genetic factors that could explain the high comorbidity of depression and fatigue.

Relationships between expression of BCS1L, mitochondrial bioenergetics, and fatigue among patients with prostate cancer.

Introduction: Cancer-related fatigue (CRF) is the most debilitating symptom with the greatest adverse side effect on quality of life. The etiology of this symptom is still not understood. The purpose of this study was to examine the relationship between mitochondrial gene expression, mitochondrial oxidative phosphorylation, electron transport chain complex activity, and fatigue in prostate cancer patients undergoing radiotherapy (XRT), compared to patients on active surveillance (AS). Methods: The study used a matched case-control and repeated-measures research design. Fatigue was measured using the revised Piper Fatigue Scale from 52 patients with prostate cancer. Mitochondrial oxidative phosphorylation, electron-transport chain enzymatic activity, and BCS1L gene expression were determined using patients' peripheral mononuclear cells. Data were collected at three time points and analyzed using repeated measures ANOVA. Results: The fatigue score was significantly different over time between patients undergoing XRT and AS (P<0.05). Patients undergoing XRT experienced significantly increased fatigue at day 21 and day 42 of XRT (P<0.01). Downregulated mitochondrial gene (BC1, ubiquinol-cytochrome c reductase, synthesis-like, BCS1L, P<0.05) expression, decreased OXPHOS-complex III oxidation (P<0.05), and reduced activity of complex III were observed over time in patients with XRT. Moreover, increased fatigue was significantly associated with downregulated BCS1L and decreased complex III oxidation in patients undergoing XRT. Conclusion: Our results suggest that BCS1L and complex III in mitochondrial mononuclear cells are potential biomarkers and feasible therapeutic targets for acute XRT-induced fatigue in this clinical population.

White matter hyperintensities and medication adherence.

White matter hyperintensities (WMH) are associated with hypertension, age, and cognitive function, but the association between WMH and medication adherence has not been examined. The intent of this investigation was to consider the potential implications of hypertension-related brain morphological changes on medication adherence and thereby improve understanding of the self-management consequences of hypertension. The associations between WMH, blood pressure, age, cognitive function (specifically assessments of prefrontal function), and medication adherence were examined in 16 middle-aged and older adults self-managing at least one prescribed antihypertensive agent. Magnetic resonance imaging using an axial fluid attenuated inversion recovery (FLAIR) sequence was used to assess the presence of WMH. Cognitive assessments included measures of executive function, working memory, attention, and immediate recall. Adherence was monitored for 8 weeks using electronic medication monitoring. More WMH were associated with poorer adherence (rs = -.25) and with higher systolic blood pressure (rs = .46), although these relationships were not statistically significant. WMH were associated with cognitive assessments in the expected direction including Digit Span Backward (rs = -.53, p < .05). Adherence was associated with immediate memory (rs = .54, p < .05) and inversely associated with failure to maintain set on the Wisconsin Card Sorting Test (WCST; rs = -.61, p < .05). These findings provide preliminary evidence for the association between WMH, assessments of prefrontal function, and medication adherence.

Integrated mitochondrial function and cancer-related fatigue in men with prostate cancer undergoing radiation therapy.

INTRODUCTION: Fatigue experienced by cancer patients is one of the most common symptoms with the greatest adverse effect on quality of life, but arguably the least understood. The purpose of this study was to explore changes in integrated mitochondrial function and fatigue in non-metastatic prostate cancer patients receiving localized radiation therapy (XRT). MATERIALS AND METHODS: We proposed a mitochondrial bioenergetics mechanism of radiation-induced fatigue linking impaired oxidative phosphorylation (OXPHOS) through complex III and decreased adenosine triphosphate (ATP) production as consequences of XRT. Integrated mitochondrial function was measured as mitochondrial OXPHOS from patients' peripheral blood mononuclear cells. Fatigue was measured using the revised Piper Fatigue Scale. Data were collected before (day 0) and at day 21 of XRT. RESULTS: At day 21 of XRT, fatigue symptom intensified in 15 prostate cancer patients (P<0.05). Mitochondrial OXPHOS complex III-linked and uncoupled complex III rates were significantly decreased in mononuclear cells at day 21 during XRT compared to that before XRT (P<0.05). Additionally, increased fatigue appeared to be associated with decreased OXPHOS complex III-linked respiration in patients undergoing XRT. CONCLUSION: Fatigue was associated with OXPHOS complex III-linked oxidation and a defect in oxidation starting at complex III in mononuclear cell mitochondria was revealed at day 21 of XRT in 15 prostate cancer patients. Complex III is a potential target for pharmacological and, in particular, nutraceutical interventions, eg, Q10, for design of interventions for CRF.

Symptoms predicting health-related quality of life in prostate cancer patients treated with localized radiation therapy.

OBJECTIVE: Patient-reported health-related quality-of-life (HRQOL) measures can provide guidance for treatment decision making, symptom management, and discharge planning. HRQOL is often influenced by the distress experienced by patients from disease or treatment-related symptoms. This study aimed to identify symptoms that can predict changes in HRQOL in men undergoing external beam radiation therapy (EBRT) for nonmetastatic prostate cancer (NMPC). METHODS: Fifty-one men with NMPC scheduled for EBRT were assessed at the baseline, at the midpoint of EBRT, and at the end of EBRT. All participants received 38-42 daily doses of EBRT (five times a week), depending on the stage of their disease. Validated questionnaires were administered to evaluate depressive symptoms, urinary and sexual functions, bowel issues, symptom-related distress, fatigue, and HRQOL. Pearson correlations, repeated-measures ANOVA, and multiple regressions examined the relationships among variables. RESULTS: Intensification of symptoms and increased symptom-related distress, with a corresponding decline in HRQOL, were observed during EBRT in men with NMPC. Changes in symptoms and symptom distress were associated with changes in HRQOL at the midpoint of EBRT (r=-0.37 to -0.6, P=0.05) and at the end of EBRT (r=-0.3 to -0.47, P=0.01) compared with the baseline. The regression model comprising age, body mass index, Gleason score, T category, androgen-deprivation therapy use, radiation dose received, symptoms (urinary/sexual/bowel problems, fatigue), and overall symptom distress explained 70% of the variance in predicting HRQOL. Urinary problems and fatigue significantly predicted the decline in HRQOL during EBRT. CONCLUSION: Identifying specific symptoms that can influence HRQOL during EBRT for NMPC can provide feasible interventional targets to improve treatment outcomes.

The negative association of independent personality and medication adherence.

OBJECTIVE: This investigation examines the association of personality factors and medication adherence among older adults. METHOD: The Six-Factor Personality Questionnaire was mailed to participants involved in a medication adherence investigation. Medication adherence was monitored with an electronic monitoring cap for 8 weeks for one prescribed daily medication. RESULTS: Sixty older adults, mean age 77 years (range 67 to 93 years), returned the questionnaire (69% response rate). Stepwise regression analysis demonstrates that when age and level of education are controlled, independence predicts medication adherence. This factor demonstrates a negative relationship with adherence suggesting that higher levels of independence may be related to lower adherence to prescribed medication. The facet component self-reliance is predictive of poor medication adherence. DISCUSSION: The finding that higher self-reliance is associated with lower adherence in an older population deserves further investigation and clinical consideration.

The Etiology and management of radiotherapy-induced fatigue.

Fatigue is one of the most common side-effects accompanying radiotherapy, but arguably the least understood. Radiotherapy-induced fatigue (RIF) is a clinical subtype of cancer treatment-related fatigue. It is described as a pervasive, subjective sense of tiredness persisting over time, interferes with activities of daily living, and is not relieved by adequate rest or sleep. RIF is one of the early side-effects and long-lasting for cancer patients treated with localized radiation. Although the underlying mechanisms of fatigue have been studied in several disease conditions, the etiology, mechanisms, and risk factors of RIF remain elusive, and this symptom remains poorly managed. The purpose of this paper is to review and discuss recent articles that defined, proposed biologic underpinnings and mechanisms to explain the pathobiology of RIF, as well as articles that proposed interventions to manage RIF. Understanding the mechanisms of RIF can describe promising pathways to identify at-risk individuals and identify potential therapeutic targets to alleviate and prevent RIF using a multimodal, multidisciplinary approach.

Genomic Profile of Fatigued Men Receiving Localized Radiation Therapy.

PURPOSE: The purpose of this study was to explore gene expression changes in fatigued men with nonmetastatic prostate cancer receiving localized external beam radiation therapy (EBRT). METHODS: Fatigue was measured in 40 men with prostate cancer (20 receiving EBRT and 20 controls on active surveillance) using the Functional Assessment of Cancer Therapy-Fatigue (FACT-F). EBRT subjects were followed from baseline to midpoint and end point of EBRT, while controls were seen at one time point. EBRT subjects were categorized into high- and low-fatigue groups based on change in FACT-F scores from baseline to EBRT completion. Full genome microarray was performed from peripheral leukocyte RNA to determine gene expression changes related to fatigue phenotypes. Real-time polymerase chain reaction and enzyme-linked immunosorbent assay confirmed the most differentially expressed gene in the microarray experiment. RESULTS: At baseline, mean FACT-F scores were not different between EBRT subjects (44.3 ± 7.16) and controls (46.7 ± 4.32, p = .24). Fatigue scores of EBRT subjects decreased at treatment midpoint (38.6 ± 9.17, p = .01) and completion (37.6 ± 9.9, p = .06), indicating worsening fatigue. Differential expression of 42 genes was observed between fatigue groups when EBRT time points were controlled. Membrane-spanning four domains, subfamily A, member (MS4A1) was the most differentially expressed gene and was associated with fatigue at treatment end point (r = -.46, p = .04). CONCLUSION: Fatigue intensification was associated with MS4A1 downregulation, suggesting that fatigue during EBRT may be related to impairment in B-cell immune response. The 42 differentially expressed fatigue-related genes are associated with glutathione biosynthesis, γ-glutamyl cycle, and antigen presentation pathways.

Biological Basis for the Clustering of Symptoms.

OBJECTIVES: Identification of biologic pathways of symptom clusters is necessary to develop precision therapies for distressing symptoms. This review examined extant literature evaluating relationships between biomarkers and symptom clusters in cancer survivors. DATA SOURCES: PubMed, CINAHL, Web of Science and Cochrane Library were searched using terms "biological markers" or "biomarkers" and "symptom cluster" or "symptom complex" or "multiple symptoms." CONCLUSION: Biomarkers related to inflammation (eg, cytokines) were the most studied and showed the most significant relationships with clusters of symptoms. This review suggests that clustering of symptoms related to cancer or cancer therapy is linked to immune/inflammatory pathways. IMPLICATIONS FOR NURSING PRACTICE: Understanding the etiology of symptom clusters may guide future nursing interventions for symptom management.

Clinical Predictors of Fatigue in Men With Non-Metastatic Prostate Cancer Receiving External Beam Radiation Therapy.

BACKGROUND: Fatigue is one of the most distressing symptoms experienced by people with cancer receiving radiation therapy. OBJECTIVES: The goal of this study is to evaluate clinical predictors of worsening fatigue during external beam radiation therapy (EBRT) in men with non-metastatic prostate cancer. METHODS: Thirty-five men with non-metastatic prostate cancer scheduled for EBRT were followed at baseline, midpoint, and completion of EBRT. The Functional Assessment of Cancer Therapy-Fatigue scale was administered. Demographic and clinical data were obtained by chart review. Paired t-tests, correlations, general linear models, and logistic regressions were used to determine associations between fatigue scores and clinical data. FINDINGS: Red blood cells, hemoglobin, and hematocrit levels were highly intercorrelated and, therefore, were grouped as one composite variable termed heme. Heme levels at baseline and androgen-deprivation therapy (ADT) were significantly correlated with worsening of fatigue symptoms from baseline to midpoint and endpoint. ADT alone did not have a significant correlation with fatigue, but it indirectly affected fatigue levels by influencing heme markers as treatment progressed. These findings provide evidence that hematologic markers and the use of ADT assist in predicting radiation therapy-related fatigue and guide symptom management.