Figure 3. ATP-induced tumor cell death is modulated via P2X7-mTOR axis.

A) Reverse transcription-PCR (RT-PCR) analysis of mRNA expression of P2 receptors in MCA38 cells. Size standards (Std) are shown in the left lane. B–C) Cell viability of MCA38 cells at 24 hr post treatment with BzATP (B) or UTP (C), as determined by CCK-8. Data are expressed as a percentage of untreated controls. D) Impacts of BzATP on AKT, AMPK, and mTOR signaling, as analyzed by Western blot. E) Blockade of P2X7 by antagonist KN62 abrogated ATP-induced inhibition on mTOR signaling in MCA38 cells, as evaluated by Western blotting. β-actin is shown as a loading control. Error bars, mean ± SEM. Data represent three to four experiments.