PTEN and gastric cancer: Noteworthy, the derivatives of Methylxanthine (caffeine and theophylline), the representative components derived from C. arabica, have been reported to induce apoptosis and autophagy in gastric cancer cells by activation of phosphatase and tensin homolog (PTEN) and inhibition of PI3K/Akt/mTOR pathway (Liu et al. 2019).