MCF-7 serum withdrawal (Agilent mouse 60K microarray)

3’deoxyadenosine, also known as cordycepin, has been widely researched as a potential treatment for cancer, yielding promising results in tissue culture as well as in pre-clinical models. A wide variety of mechanisms of action have been proposed, with little agreement between different studies. Here, we confirm that cordycepin triphosphate is likely to be the active metabolite of cordycepin. Data from single and high throughput experiments showed that cordycepin represses growth factor induced gene expression. Bioinformatic analysis, quantitative PCR and western blotting confirmed that cordycepin blocks the PI3K/AKT/mTOR and/or MEK/ERK pathways in 6 cell lines. Effects of cordycepin on translation through mTOR pathway repression were detectable within 30 minutes, indicating a rapid process. Our data show that cordycepin has a broadly similar mechanism of action in all cell lines studied and indicate that its therapeutic target is a cordycepin triphosphate sensitive molecule that is required for growth factor signal transduction. MCF-7 cells were incubated for four hours in serum free medium (serum withdrawal) or kept in the medium in which they were seeded (control), total RNA was isolated and microarray analysis performed.