Relationship of Mitochondrial Enzymes to Fatigue Intensity in Men With Prostate Cancer Receiving External Beam Radiation Therapy.

PURPOSE: Mitochondrial dysfunction is a plausible biological mechanism for cancer-related fatigue. Specific aims of this study were to (1) describe the levels of mitochondrial oxidative phosphorylation complex (MOPC) enzymes, fatigue, and health-related quality of life (HRQOL) before and at completion of external beam radiation therapy (EBRT) in men with nonmetastatic prostate cancer (PC); (2) examine relationships over time among levels of MOPC enzymes, fatigue, and HRQOL; and (3) compare levels of MOPC enzymes in men with clinically significant and nonsignificant fatigue intensification during EBRT. METHODS: Fatigue was measured by the revised Piper Fatigue Scale and the Functional Assessment of Cancer Therapy-Fatigue subscale (FACT-F). MOPC enzymes (Complexes I-V) and mitochondrial antioxidant superoxide dismutase 2 were measured in peripheral blood using enzyme-linked immunosorbent assay at baseline and completion of EBRT. Participants were categorized into high or low fatigue (HF vs. LF) intensification groups based on amount of change in FACT-F scores during EBRT. RESULTS: Fatigue reported by the 22 participants with PC significantly worsened and HRQOL significantly declined from baseline to EBRT completion. The HF group comprised 12 men with clinically significant change in fatigue (HF) during EBRT. Although no significant changes were observed in MOPC enzymes from baseline to EBRT completion, there were important differences in the patterns in the levels of MOPC enzymes between HF and LF groups. CONCLUSION: Distinct patterns of changes in the absorbance of MOPC enzymes delineated fatigue intensification among participants. Further investigation using a larger sample is warranted.

The biology of cancer-related fatigue: a review of the literature.

PURPOSE: Understanding the etiology of cancer-related fatigue (CRF) is critical to identify targets to develop therapies to reduce CRF burden. The goal of this systematic review was to expand on the initial work by the National Cancer Institute CRF Working Group to understand the state of the science related to the biology of CRF and, specifically, to evaluate studies that examined the relationships between biomarkers and CRF and to develop an etiologic model of CRF to guide researchers on pathways to explore or therapeutic targets to investigate. METHODS: This review was completed by the Multinational Association of Supportive Care in Cancer Fatigue Study Group-Biomarker Working Group. The initial search used three terms (biomarkers, fatigue, cancer), which yielded 11,129 articles. After removing duplicates, 9145 articles remained. Titles were assessed for the keywords "cancer" and "fatigue" resulting in 3811 articles. Articles published before 2010 and those with samples <50 were excluded, leaving 75 articles for full-text review. Of the 75 articles, 28 were further excluded for not investigating the associations of biomarkers and CRF. RESULTS: Of the 47 articles reviewed, 25 were cross-sectional and 22 were longitudinal studies. More than half (about 70 %) were published recently (2010-2013). Almost half (45 %) enrolled breast cancer participants. The majority of studies assessed fatigue using self-report questionnaires, and only two studies used clinical parameters to measure fatigue. CONCLUSIONS: The findings from this review suggest that CRF is linked to immune/inflammatory, metabolic, neuroendocrine, and genetic biomarkers. We also identified gaps in knowledge and made recommendations for future research.

Association of Mitochondrial Dysfunction and Fatigue: A Review of the Literature.

Fatigue is often described by patients as a lack of energy, mental or physical tiredness, diminished endurance, and prolonged recovery after physical activity. Etiologic mechanisms underlying fatigue are not well understood; however, fatigue is a hallmark symptom of mitochondrial disease, making mitochondrial dysfunction a putative biological mechanism for fatigue. Therefore, this review examined studies that investigated the association of markers of mitochondrial dysfunction with fatigue and proposes possible research directions to enhance understanding of the role of mitochondrial dysfunction in fatigue. A thorough search using PubMed, Scopus, Web of Science, and Embase databases returned 1,220 articles. After application of inclusion and exclusion criteria, a total of 25 articles meeting eligibility criteria were selected for full review. Dysfunctions in the mitochondrial structure, mitochondrial function (mitochondrial enzymes and oxidative/nitrosative stress), mitochondrial energy metabolism (ATP production and fatty acid metabolism), immune response, and genetics were investigated as potential contributors to fatigue. Carnitine was the most investigated mitochondrial function marker. Dysfunctional levels were reported in all the studies investigating carnitine; however, the specific type of carnitine that was dysfunctional varied. Genetic profiles were the second most studied mitochondrial parameter. Six common pathways were proposed: metabolism, energy production, protein transport, mitochondrial morphology, central nervous system dysfunction and post-viral infection. Coenzyme Q10 was the most commonly investigated mitochondrial enzyme. Low levels of Coenzyme Q10 were consistently associated with fatigue. Potential targets for further investigation were identified as well as gaps in the current literature.

Telomere length: a review of methods for measurement.

BACKGROUND: The exciting discovery that telomere shortening is associated with many health conditions and that telomere lengths can be altered in response to social and environmental exposures has underscored the need for methods to accurately and consistently quantify telomere length. OBJECTIVES: The purpose of this article is to provide a comprehensive summary that compares and contrasts the current technologies used to assess telomere length. DISCUSSION: Multiple methods have been developed for the study of telomeres. These techniques include quantification of telomere length by terminal restriction fragmentation-which was one of the earliest tools used for length assessment-making it the gold standard in telomere biology. Quantitative polymerase chain reaction provides the advantage of being able to use smaller amounts of DNA, thereby making it amenable to epidemiology studies involving large numbers of people. An alternative method uses fluorescent probes to quantify not only mean telomere lengths but also chromosome-specific telomere lengths; however, the downside of this approach is that it can only be used on mitotically active cells. Additional methods that permit assessment of the length of a subset of chromosome-specific telomeres or the subset of telomeres that demonstrate shortening are also reviewed. CONCLUSION: Given the increased utility for telomere assessments as a biomarker in physiological, psychological, and biobehavioral research, it is important that investigators become familiar with the methodological nuances of the various procedures used for measuring telomere length. This will ensure that they are empowered to select an optimal assessment approach to meet the needs of their study designs. Gaining a better understanding of the benefits and drawbacks of various measurement techniques is important not only in individual studies, but also to further establish the science of telomere associations with biobehavioral phenomena.

An integrative review of factors associated with telomere length and implications for biobehavioral research.

BACKGROUND: Although telomere shortening occurs as a natural part of aging, there is now a robust body of research that suggests that there is a relationship between psychosocial, environmental, and behavioral factors and changes in telomere length. These factors need to be considered when integrating telomere measurement in biobehavioral research studies. OBJECTIVES: This article provides a brief summary of the known facts about telomere biology and an integrative review of current human research studies that assessed relationships between psychosocial, environmental, or behavioral factors and telomere length. METHODS: An integrative review was conducted to examine human research studies that focused on psychosocial, environmental, and behavioral factors affecting telomere length and telomerase activity using the electronic databases PubMed/Medline and CINAHL from 2003 to the present. In addition to the known individual factors that are associated with telomere length, the results of the integrative review suggest that perceived stress, childhood adversities, major depressive disorder, educational attainment, physical activity, and sleep duration should also be measured. DISCUSSION: Multiple factors have been shown to affect telomere length. To advance understanding of the role of telomere length in health and disease risk, it will be important to further elucidate the mechanisms that contribute to telomere shortening.

Fall risk in adult inpatients with leukemia undergoing induction chemotherapy.

Falls are a major concern for patients with acute myeloid leukemia who are admitted to the hospital for induction chemotherapy. Patients with cancer are at risk for rapidly changing health status and, therefore, need a different kind of fall surveillance than those in other inpatient units. Fall risk most likely will change throughout an inpatient's stay. Oncology nurses can start addressing this issue by reviewing the documented data of falls in this patient population.

Back pain caused by a solitary plasmacytoma of bone.

This article presents initial diagnostic workup and criteria for diagnosing solitary plasmacytoma of bone (SPB) versus multiple myeloma. The authors discuss the incorporation of current imaging technologies into the diagnosis and staging of SPB and multiple myeloma. In addition, the article addresses treatment modalities and discusses the importance of oncology nurses' awareness of this rare condition.