Figure 6: Reduced p70S6K phosphorylation in breast carcinoma effusions compared to primary tumors. mTOR activity measured by Western blot analysis of the mTORC1 substrate p70S6K phosphorylation extent in effusions (n=16) and primary tumors (n=22). Phosphorylated p70-S6K protein levels were analyzed using phospho-specific antibodies and normalized to total p70S6K levels. The 3T3-NIH cell line served as a positive control.