MTOR and diffuse large B-cell lymphoma: The activation of the PI3K/protein kinase B (AKT)/mammalian target of the rapamycin (mTOR) pathway also plays a key role in lymphoma, and many signaling pathway inhibitors have been developed to treat FL, DLBCL, MCL, small lymphocytic, and T-cell NHL [153,154,155,156,157].