Exploratory Analysis of Associations Between Whole Blood Mitochondrial Gene Expression and Cancer-Related Fatigue Among Breast Cancer Survivors
Nurs Res. 2022 Apr 13. doi: 10.1097/NNR.0000000000000598. Online ahead of print.
ABSTRACT
BACKGROUND: Cancer-related fatigue is a prevalent, debilitating, and persistent condition. Mitochondrial dysfunction is a putative contributor to cancer-related fatigue, but relationships between mitochondrial function and cancer-related fatigue are not well understood.
OBJECTIVES: We investigated the relationships between mitochondrial DNA (mtDNA) gene expression and cancer-related fatigue, as well as the effects of fish and soybean oil supplementation on these relationships.
METHODS: A secondary analysis was performed on data from a randomized controlled trial of breast cancer survivors 4-36 months posttreatment with moderate-severe cancer-related fatigue. Participants were randomized to take 6 g fish oil, 6 g soybean oil, or 3 g each daily for 6 weeks. At pre- and postintervention, participants completed the Functional Assessment of Chronic Illness Therapy-Fatigue questionnaire and provided whole blood for assessment of mtDNA gene expression. The expression of 12 protein-encoding genes was reduced to a single dimension using principal component analysis for use in regression analysis. Relationships between mtDNA expression and cancer-related fatigue were assessed using linear regression.
RESULTS: Among 68 participants, cancer-related fatigue improved and expression of all mtDNA genes decreased over 6 weeks with no effect of treatment group on either outcome. Participants with lower baseline mtDNA gene expression had greater improvements in cancer-related fatigue. No significant associations were observed between mtDNA gene expression and cancer-related fatigue at baseline or changes in mtDNA gene expression and changes in cancer-related fatigue.
DISCUSSION: Data from this exploratory study add to the growing literature that mitochondrial dysfunction may contribute to the etiology and pathophysiology of cancer-related fatigue.
PMID:35416182 | DOI:10.1097/NNR.0000000000000598