NHL cell lines Toledo, NK-92, RL, and Farage were all purchased from American Type Culture Collection (VA, USA). Toledo, Farage, and RL cells were cultured in RPMI-1640 medium containing 10% FBS (Gibco, CA, USA); NK-92 cells were cultured in Alpha Minimum Essential Medium with ribonucleosides and deoxyribonucleosides free while with 2 mM L-glutamine and 1.5 g/L sodium bicarbonate, 0.2 mM inositol, 0.1 mM 2-mercaptoethanol, 0.02 mM folic acid, 100–200 U/mL recombinant IL-2, 12.5% horse serum (Sigma-Aldrich Co., St Louis, MO, USA), and 12.5% FBS.
Toledo or NK-92 cells were incubated with different concentrations of forskolin (0, 10, 20, 40, 80, or 160 μM; cAMP analog 8-pCPT-2′-OMe-cAMP; Sigma-Aldrich Co) for the indicated times, and 20 μM of SP600125 (Selleck Chemicals, Shanghai, China), an inhibitor of c-Jun N-terminal kinase (JNK) for 24 hours.
Toledo or NK-92 cells were incubated with different concentrations of forskolin (0, 10, 20, 40, 80, or 160 μM; cAMP analog 8-pCPT-2′-OMe-cAMP; Sigma-Aldrich Co) for the indicated times, and 20 μM of SP600125 (Selleck Chemicals, Shanghai, China), an inhibitor of c-Jun N-terminal kinase (JNK) for 24 hours.