Gene Expression Analysis of the mTOR Pathway: Association with Radiation Therapy-Related Fatigue.

OBJECTIVE

To examine whether changes in the expression of 40 preselected mammalian target of rapamycin complex 1 (mTOR) pathway-related genes were associated with changes in fatigue scores during external beam radiation therapy (EBRT) to treat prostate cancer.

METHODS

A total of 26 men completed the Functional Assessment of Cancer Therapy-Fatigue subscale and provided whole blood samples at baseline and at the midpoint of EBRT. Microarray gene expression data were analyzed using the limma package in R. Associations between changes in gene expression and changes in fatigue scores were computed using linear models and empirical Bayes moderation, with adjustment for radiation fraction.

RESULTS

After adjusting for radiation fraction, changes in the expression of 24 of 40 preselected genes were significantly associated with changes in fatigue during EBRT (false discovery rate < .05).

CONCLUSION

Findings suggest that mTOR-related genes may play a role in radiation therapy-related fatigue; validation of these implicated genes in an independent cohort is warranted.