Western Blot analysis using tumor extracts after short-term in vivo treatment (7 days) proved on-target activity of the drug (Supplementary Fig. 11C) whereas the levels of phosphorylated S6 ribosomal protein consistently increased upon prolonged therapy, consistent with the late-stage tumor re-growth following the strong initial response to the drug (Supplementary Fig. 10D). Here, RPS6 is linked to neoplasm.