DNA Methylation of BDNF and RASA2 Genes Is Associated With Cognitive Function in Postmenopausal Women With Breast Cancer.

OBJECTIVES: To determine associations among DNA methylation of brain-derived neurotrophic factor (BDNF) and RAS p21 protein activator 2 (RASA2) genes with processing speed and perceived cognitive function. SAMPLE & SETTING: This was a cross-sectional, secondary analysis of baseline data from a randomized controlled trial, the Exercise Program in Cancer and Cognition Study. METHODS & VARIABLES: Data included M values for DNA methylation of the BDNF and RASA2 genes; processing speed, objectively measured using the Grooved Pegboard and Digit Vigilance Test scores; and perceived cognitive function, self-reported using the Patient Assessment of Own Functioning Inventory. Regression analysis was conducted. RESULTS: Greater methylation of cg21291635 of the BDNF gene (p = 0.01) and cg20247102 of the RASA2 gene (p = 0.013) were associated with poorer processing speed, whereas greater methylation of cg20108357 of the BDNF gene (p < 0.001) and cg00567892 of the RASA2 gene (p = 0.019) were associated with better perceived cognitive function. IMPLICATIONS FOR NURSING: Gene methylation variations were demonstrated, suggesting the genes' potential roles and two possible distinct mechanisms of cognitive function in cancer. [ABSTRACT FROM AUTHOR]